\input texinfo @c -*-texinfo-*- @c %**start of header @setfilename openocd.info @settitle OpenOCD User's Guide @dircategory Development @direntry * OpenOCD: (openocd). OpenOCD User's Guide @end direntry @paragraphindent 0 @c %**end of header @include version.texi @copying This User's Guide documents release @value{VERSION}, dated @value{UPDATED}, of the Open On-Chip Debugger (OpenOCD). @itemize @bullet @item Copyright @copyright{} 2008 The OpenOCD Project @item Copyright @copyright{} 2007-2008 Spencer Oliver @email{spen@@spen-soft.co.uk} @item Copyright @copyright{} 2008 Oyvind Harboe @email{oyvind.harboe@@zylin.com} @item Copyright @copyright{} 2008 Duane Ellis @email{openocd@@duaneellis.com} @end itemize @quotation Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts. A copy of the license is included in the section entitled ``GNU Free Documentation License''. @end quotation @end copying @titlepage @titlefont{@emph{Open On-Chip Debugger:}} @sp 1 @title OpenOCD User's Guide @subtitle for release @value{VERSION} @subtitle @value{UPDATED} @page @vskip 0pt plus 1filll @insertcopying @end titlepage @summarycontents @contents @ifnottex @node Top @top OpenOCD User's Guide @insertcopying @end ifnottex @menu * About:: About OpenOCD * Developers:: OpenOCD Developers * Building OpenOCD:: Building OpenOCD From SVN * JTAG Hardware Dongles:: JTAG Hardware Dongles * Running:: Running OpenOCD * Simple Configuration Files:: Simple Configuration Files * Config File Guidelines:: Config File Guidelines * About JIM-Tcl:: About JIM-Tcl * Daemon Configuration:: Daemon Configuration * Interface - Dongle Configuration:: Interface - Dongle Configuration * Reset Configuration:: Reset Configuration * Tap Creation:: Tap Creation * Target Configuration:: Target Configuration * Flash Commands:: Flash Commands * NAND Flash Commands:: NAND Flash Commands * General Commands:: General Commands * Architecture and Core Commands:: Architecture and Core Commands * JTAG Commands:: JTAG Commands * Sample Scripts:: Sample Target Scripts * TFTP:: TFTP * GDB and OpenOCD:: Using GDB and OpenOCD * Tcl Scripting API:: Tcl Scripting API * Upgrading:: Deprecated/Removed Commands * Target Library:: Target Library * FAQ:: Frequently Asked Questions * Tcl Crash Course:: Tcl Crash Course * License:: GNU Free Documentation License @comment DO NOT use the plain word ``Index'', reason: CYGWIN filename @comment case issue with ``Index.html'' and ``index.html'' @comment Occurs when creating ``--html --no-split'' output @comment This fix is based on: http://sourceware.org/ml/binutils/2006-05/msg00215.html * OpenOCD Concept Index:: Concept Index * Command and Driver Index:: Command and Driver Index @end menu @node About @unnumbered About @cindex about OpenOCD was created by Dominic Rath as part of a diploma thesis written at the University of Applied Sciences Augsburg (@uref{http://www.fh-augsburg.de}). Since that time, the project has grown into an active open-source project, supported by a diverse community of software and hardware developers from around the world. @section What is OpenOCD? The Open On-Chip Debugger (OpenOCD) aims to provide debugging, in-system programming and boundary-scan testing for embedded target devices. @b{JTAG:} OpenOCD uses a ``hardware interface dongle'' to communicate with the JTAG (IEEE 1149.1) compliant taps on your target board. @b{Dongles:} OpenOCD currently supports many types of hardware dongles: USB based, parallel port based, and other standalone boxes that run OpenOCD internally. @xref{JTAG Hardware Dongles}. @b{GDB Debug:} It allows ARM7 (ARM7TDMI and ARM720t), ARM9 (ARM920T, ARM922T, ARM926EJ--S, ARM966E--S), XScale (PXA25x, IXP42x) and Cortex-M3 (Stellaris LM3 and ST STM32) based cores to be debugged via the GDB protocol. @b{Flash Programing:} Flash writing is supported for external CFI compatible NOR flashes (Intel and AMD/Spansion command set) and several internal flashes (LPC2000, AT91SAM7, STR7x, STR9x, LM3, and STM32x). Preliminary support for various NAND flash controllers (LPC3180, Orion, S3C24xx, more) controller is included. @section OpenOCD Web Site The OpenOCD web site provides the latest public news from the community: @uref{http://openocd.berlios.de/web/} @section Latest User's Guide: The user's guide you are now reading may not be the latest one available. A version for more recent code may be available. Its HTML form is published irregularly at: @uref{http://openocd.berlios.de/doc/} PDF form is likewise published at: @uref{http://openocd.berlios.de/doc/pdf/} @section OpenOCD User's Forum There is an OpenOCD forum (phpBB) hosted by SparkFun: @uref{http://forum.sparkfun.com/viewforum.php?f=18} @node Developers @chapter OpenOCD Developer Resources @cindex developers If you are interested in improving the state of OpenOCD's debugging and testing support, new contributions will be welcome. Motivated developers can produce new target, flash or interface drivers, improve the documentation, as well as more conventional bug fixes and enhancements. The resources in this chapter are available for developers wishing to explore or expand the OpenOCD source code. @section OpenOCD Subversion Repository The ``Building From Source'' section provides instructions to retrieve and and build the latest version of the OpenOCD source code. @xref{Building OpenOCD}. Developers that want to contribute patches to the OpenOCD system are @b{strongly} encouraged to base their work off of the most recent trunk revision. Patches created against older versions may require additional work from their submitter in order to be updated for newer releases. @section Doxygen Developer Manual During the development of the 0.2.0 release, the OpenOCD project began providing a Doxygen reference manual. This document contains more technical information about the software internals, development processes, and similar documentation: @uref{http://openocd.berlios.de/doc/doxygen/index.html} This document is a work-in-progress, but contributions would be welcome to fill in the gaps. All of the source files are provided in-tree, listed in the Doxyfile configuration in the top of the repository trunk. @section OpenOCD Developer Mailing List The OpenOCD Developer Mailing List provides the primary means of communication between developers: @uref{https://lists.berlios.de/mailman/listinfo/openocd-development} All drivers developers are enouraged to also subscribe to the list of SVN commits to keep pace with the ongoing changes: @uref{https://lists.berlios.de/mailman/listinfo/openocd-svn} @node Building OpenOCD @chapter Building OpenOCD @cindex building @section Pre-Built Tools If you are interested in getting actual work done rather than building OpenOCD, then check if your interface supplier provides binaries for you. Chances are that that binary is from some SVN version that is more stable than SVN trunk where bleeding edge development takes place. @section Packagers Please Read! You are a @b{PACKAGER} of OpenOCD if you @enumerate @item @b{Sell dongles} and include pre-built binaries @item @b{Supply tools} i.e.: A complete development solution @item @b{Supply IDEs} like Eclipse, or RHIDE, etc. @item @b{Build packages} i.e.: RPM files, or DEB files for a Linux Distro @end enumerate As a @b{PACKAGER}, you will experience first reports of most issues. When you fix those problems for your users, your solution may help prevent hundreds (if not thousands) of other questions from other users. If something does not work for you, please work to inform the OpenOCD developers know how to improve the system or documentation to avoid future problems, and follow-up to help us ensure the issue will be fully resolved in our future releases. That said, the OpenOCD developers would also like you to follow a few suggestions: @enumerate @item @b{Always build with printer ports enabled.} @item @b{Try to use LIBFTDI + LIBUSB where possible. You cover more bases.} @end enumerate @itemize @bullet @item @b{Why YES to LIBFTDI + LIBUSB?} @itemize @bullet @item @b{LESS} work - libusb perhaps already there @item @b{LESS} work - identical code, multiple platforms @item @b{MORE} dongles are supported @item @b{MORE} platforms are supported @item @b{MORE} complete solution @end itemize @item @b{Why not LIBFTDI + LIBUSB} (i.e.: ftd2xx instead)? @itemize @bullet @item @b{LESS} speed - some say it is slower @item @b{LESS} complex to distribute (external dependencies) @end itemize @end itemize @section Building From Source You can download the current SVN version with an SVN client of your choice from the following repositories: @uref{svn://svn.berlios.de/openocd/trunk} or @uref{http://svn.berlios.de/svnroot/repos/openocd/trunk} Using the SVN command line client, you can use the following command to fetch the latest version (make sure there is no (non-svn) directory called "openocd" in the current directory): @example svn checkout svn://svn.berlios.de/openocd/trunk openocd @end example If you prefer GIT based tools, the @command{git-svn} package works too: @example git svn clone -s svn://svn.berlios.de/openocd @end example Building OpenOCD from a repository requires a recent version of the GNU autotools (autoconf >= 2.59 and automake >= 1.9). For building on Windows, you have to use Cygwin. Make sure that your @env{PATH} environment variable contains no other locations with Unix utils (like UnxUtils) - these can't handle the Cygwin paths, resulting in obscure dependency errors (This is an observation I've gathered from the logs of one user - correct me if I'm wrong). You further need the appropriate driver files, if you want to build support for a FTDI FT2232 based interface: @itemize @bullet @item @b{ftdi2232} libftdi (@uref{http://www.intra2net.com/opensource/ftdi/}) @item @b{ftd2xx} libftd2xx (@uref{http://www.ftdichip.com/Drivers/D2XX.htm}) @item When using the Amontec JTAGkey, you have to get the drivers from the Amontec homepage (@uref{http://www.amontec.com}). The JTAGkey uses a non-standard VID/PID. @end itemize libftdi is supported under Windows. Do not use versions earlier than 0.14. In general, the D2XX driver provides superior performance (several times as fast), but has the draw-back of being binary-only - though that isn't that bad, as it isn't a kernel module, only a user space library. To build OpenOCD (on both Linux and Cygwin), use the following commands: @example ./bootstrap @end example Bootstrap generates the configure script, and prepares building on your system. @example ./configure [options, see below] @end example Configure generates the Makefiles used to build OpenOCD. @example make make install @end example Make builds OpenOCD, and places the final executable in ./src/, the last step, ``make install'' is optional. The configure script takes several options, specifying which JTAG interfaces should be included (among other things): @itemize @bullet @item @option{--enable-parport} - Enable building the PC parallel port driver. @item @option{--enable-parport_ppdev} - Enable use of ppdev (/dev/parportN) for parport. @item @option{--enable-parport_giveio} - Enable use of giveio for parport instead of ioperm. @item @option{--enable-amtjtagaccel} - Enable building the Amontec JTAG-Accelerator driver. @item @option{--enable-ecosboard} - Enable building support for eCosBoard based JTAG debugger. @item @option{--enable-ioutil} - Enable ioutil functions - useful for standalone OpenOCD implementations. @item @option{--enable-httpd} - Enable builtin httpd server - useful for standalone OpenOCD implementations. @item @option{--enable-ep93xx} - Enable building support for EP93xx based SBCs. @item @option{--enable-at91rm9200} - Enable building support for AT91RM9200 based SBCs. @item @option{--enable-gw16012} - Enable building support for the Gateworks GW16012 JTAG programmer. @item @option{--enable-ft2232_ftd2xx} - Numerous USB type ARM JTAG dongles use the FT2232C chip from this FTDICHIP.COM chip (closed source). @item @option{--enable-ft2232_libftdi} - An open source (free) alternative to FTDICHIP.COM ftd2xx solution (Linux, MacOS, Cygwin). @item @option{--with-ftd2xx-win32-zipdir=PATH} - If using FTDICHIP.COM ft2232c driver, give the directory where the Win32 FTDICHIP.COM 'CDM' driver zip file was unpacked. @item @option{--with-ftd2xx-linux-tardir=PATH} - If using FTDICHIP.COM ft2232c driver on Linux, give the directory where the Linux driver's TAR.GZ file was unpacked. @item @option{--with-ftd2xx-lib=shared|static} - Linux only. Default: static. Specifies how the FTDICHIP.COM libftd2xx driver should be linked. Note: 'static' only works in conjunction with @option{--with-ftd2xx-linux-tardir}. The 'shared' value is supported (12/26/2008), however you must manually install the required header files and shared libraries in an appropriate place. This uses ``libusb'' internally. @item @option{--enable-presto_libftdi} - Enable building support for ASIX Presto programmer using the libftdi driver. @item @option{--enable-presto_ftd2xx} - Enable building support for ASIX Presto programmer using the FTD2XX driver. @item @option{--enable-usbprog} - Enable building support for the USBprog JTAG programmer. @item @option{--enable-oocd_trace} - Enable building support for the OpenOCD+trace ETM capture device. @item @option{--enable-jlink} - Enable building support for the Segger J-Link JTAG programmer. @item @option{--enable-vsllink} - Enable building support for the Versaloon-Link JTAG programmer. @item @option{--enable-rlink} - Enable building support for the Raisonance RLink JTAG programmer. @item @option{--enable-arm-jtag-ew} - Enable building support for the Olimex ARM-JTAG-EW programmer. @item @option{--enable-dummy} - Enable building the dummy port driver. @end itemize @section Parallel Port Dongles If you want to access the parallel port using the PPDEV interface you have to specify both the @option{--enable-parport} AND the @option{--enable-parport_ppdev} option since the @option{--enable-parport_ppdev} option actually is an option to the parport driver (see @uref{http://forum.sparkfun.com/viewtopic.php?t=3795} for more info). The same is true for the @option{--enable-parport_giveio} option, you have to use both the @option{--enable-parport} AND the @option{--enable-parport_giveio} option if you want to use giveio instead of ioperm parallel port access method. @section FT2232C Based USB Dongles There are 2 methods of using the FTD2232, either (1) using the FTDICHIP.COM closed source driver, or (2) the open (and free) driver libftdi. Some claim the (closed) FTDICHIP.COM solution is faster. The FTDICHIP drivers come as either a (win32) ZIP file, or a (Linux) TAR.GZ file. You must unpack them ``some where'' convient. As of this writing (12/26/2008) FTDICHIP does not supply means to install these files ``in an appropriate place'' As a result, there are two ``./configure'' options that help. Below is an example build process: @enumerate @item Check out the latest version of ``openocd'' from SVN. @item If you are using the FTDICHIP.COM driver, download and unpack the Windows or Linux FTD2xx drivers (@uref{http://www.ftdichip.com/Drivers/D2XX.htm}). If you are using the libftdi driver, install that package (e.g. @command{apt-get install libftdi} on systems with APT). @example /home/duane/ftd2xx.win32 => the Cygwin/Win32 ZIP file contents /home/duane/libftd2xx0.4.16 => the Linux TAR.GZ file contents @end example @item Configure with options resembling the following. @enumerate a @item Cygwin FTDICHIP solution: @example ./configure --prefix=/home/duane/mytools \ --enable-ft2232_ftd2xx \ --with-ftd2xx-win32-zipdir=/home/duane/ftd2xx.win32 @end example @item Linux FTDICHIP solution: @example ./configure --prefix=/home/duane/mytools \ --enable-ft2232_ftd2xx \ --with-ft2xx-linux-tardir=/home/duane/libftd2xx0.4.16 @end example @item Cygwin/Linux LIBFTDI solution ... assuming that @itemize @item For Windows -- that the Windows port of LIBUSB is in place. @item For Linux -- that libusb has been built/installed and is in place. @item That libftdi has been built and installed (relies on libusb). @end itemize Then configure the libftdi solution like this: @example ./configure --prefix=/home/duane/mytools \ --enable-ft2232_libftdi @end example @end enumerate @item Then just type ``make'', and perhaps ``make install''. @end enumerate @section Miscellaneous Configure Options @itemize @bullet @item @option{--disable-option-checking} - Ignore unrecognized @option{--enable} and @option{--with} options. @item @option{--enable-gccwarnings} - Enable extra gcc warnings during build. Default is enabled. @item @option{--enable-release} - Enable building of an OpenOCD release, generally this is for developers. It simply omits the svn version string when the openocd @option{-v} is executed. @end itemize @node JTAG Hardware Dongles @chapter JTAG Hardware Dongles @cindex dongles @cindex FTDI @cindex wiggler @cindex zy1000 @cindex printer port @cindex USB Adapter @cindex rtck Defined: @b{dongle}: A small device that plugins into a computer and serves as an adapter .... [snip] In the OpenOCD case, this generally refers to @b{a small adapater} one attaches to your computer via USB or the Parallel Printer Port. The execption being the Zylin ZY1000 which is a small box you attach via an ethernet cable. The Zylin ZY1000 has the advantage that it does not require any drivers to be installed on the developer PC. It also has a built in web interface. It supports RTCK/RCLK or adaptive clocking and has a built in relay to power cycle targets remotely. @section Choosing a Dongle There are three things you should keep in mind when choosing a dongle. @enumerate @item @b{Voltage} What voltage is your target? 1.8, 2.8, 3.3, or 5V? Does your dongle support it? @item @b{Connection} Printer Ports - Does your computer have one? @item @b{Connection} Is that long printer bit-bang cable practical? @item @b{RTCK} Do you require RTCK? Also known as ``adaptive clocking'' @end enumerate @section Stand alone Systems @b{ZY1000} See: @url{http://www.zylin.com/zy1000.html} Technically, not a dongle, but a standalone box. The ZY1000 has the advantage that it does not require any drivers installed on the developer PC. It also has a built in web interface. It supports RTCK/RCLK or adaptive clocking and has a built in relay to power cycle targets remotely. @section USB FT2232 Based There are many USB JTAG dongles on the market, many of them are based on a chip from ``Future Technology Devices International'' (FTDI) known as the FTDI FT2232; this is a USB full speed (12 Mbps) chip. See: @url{http://www.ftdichip.com} for more information. In summer 2009, USB high speed (480 Mbps) versions of these FTDI chips are starting to become available in JTAG adapters. As of 28/Nov/2008, the following are supported: @itemize @bullet @item @b{usbjtag} @* Link @url{http://www.hs-augsburg.de/~hhoegl/proj/usbjtag/usbjtag.html} @item @b{jtagkey} @* See: @url{http://www.amontec.com/jtagkey.shtml} @item @b{oocdlink} @* See: @url{http://www.oocdlink.com} By Joern Kaipf @item @b{signalyzer} @* See: @url{http://www.signalyzer.com} @item @b{evb_lm3s811} @* See: @url{http://www.luminarymicro.com} - The Stellaris LM3S811 eval board has an FTD2232C chip built in. @item @b{olimex-jtag} @* See: @url{http://www.olimex.com} @item @b{flyswatter} @* See: @url{http://www.tincantools.com} @item @b{turtelizer2} @* See: @uref{http://www.ethernut.de/en/hardware/turtelizer/index.html, Turtelizer 2}, or @url{http://www.ethernut.de} @item @b{comstick} @* Link: @url{http://www.hitex.com/index.php?id=383} @item @b{stm32stick} @* Link @url{http://www.hitex.com/stm32-stick} @item @b{axm0432_jtag} @* Axiom AXM-0432 Link @url{http://www.axman.com} @item @b{cortino} @* Link @url{http://www.hitex.com/index.php?id=cortino} @end itemize @section USB JLINK based There are several OEM versions of the Segger @b{JLINK} adapter. It is an example of a micro controller based JTAG adapter, it uses an AT91SAM764 internally. @itemize @bullet @item @b{ATMEL SAMICE} Only works with ATMEL chips! @* Link: @url{http://www.atmel.com/dyn/products/tools_card.asp?tool_id=3892} @item @b{SEGGER JLINK} @* Link: @url{http://www.segger.com/jlink.html} @item @b{IAR J-Link} @* Link: @url{http://www.iar.com/website1/1.0.1.0/369/1/index.php} @end itemize @section USB RLINK based Raisonance has an adapter called @b{RLink}. It exists in a stripped-down form on the STM32 Primer, permanently attached to the JTAG lines. It also exists on the STM32 Primer2, but that is wired for SWD and not JTAG, thus not supported. @itemize @bullet @item @b{Raisonance RLink} @* Link: @url{http://www.raisonance.com/products/RLink.php} @item @b{STM32 Primer} @* Link: @url{http://www.stm32circle.com/resources/stm32primer.php} @item @b{STM32 Primer2} @* Link: @url{http://www.stm32circle.com/resources/stm32primer2.php} @end itemize @section USB Other @itemize @bullet @item @b{USBprog} @* Link: @url{http://www.embedded-projects.net/usbprog} - which uses an Atmel MEGA32 and a UBN9604 @item @b{USB - Presto} @* Link: @url{http://tools.asix.net/prg_presto.htm} @item @b{Versaloon-Link} @* Link: @url{http://www.simonqian.com/en/Versaloon} @item @b{ARM-JTAG-EW} @* Link: @url{http://www.olimex.com/dev/arm-jtag-ew.html} @end itemize @section IBM PC Parallel Printer Port Based The two well known ``JTAG Parallel Ports'' cables are the Xilnx DLC5 and the MacGraigor Wiggler. There are many clones and variations of these on the market. @itemize @bullet @item @b{Wiggler} - There are many clones of this. @* Link: @url{http://www.macraigor.com/wiggler.htm} @item @b{DLC5} - From XILINX - There are many clones of this @* Link: Search the web for: ``XILINX DLC5'' - it is no longer produced, PDF schematics are easily found and it is easy to make. @item @b{Amontec - JTAG Accelerator} @* Link: @url{http://www.amontec.com/jtag_accelerator.shtml} @item @b{GW16402} @* Link: @url{http://www.gateworks.com/products/avila_accessories/gw16042.php} @item @b{Wiggler2} @*@uref{http://www.ccac.rwth-aachen.de/@/~michaels/@/index.php/hardware/@/armjtag, Improved parallel-port wiggler-style JTAG adapter} @item @b{Wiggler_ntrst_inverted} @* Yet another variation - See the source code, src/jtag/parport.c @item @b{old_amt_wiggler} @* Unknown - probably not on the market today @item @b{arm-jtag} @* Link: Most likely @url{http://www.olimex.com/dev/arm-jtag.html} [another wiggler clone] @item @b{chameleon} @* Link: @url{http://www.amontec.com/chameleon.shtml} @item @b{Triton} @* Unknown. @item @b{Lattice} @* ispDownload from Lattice Semiconductor @url{http://www.latticesemi.com/lit/docs/@/devtools/dlcable.pdf} @item @b{flashlink} @* From ST Microsystems; @uref{http://www.st.com/stonline/@/products/literature/um/7889.pdf, FlashLINK JTAG programing cable for PSD and uPSD} @end itemize @section Other... @itemize @bullet @item @b{ep93xx} @* An EP93xx based Linux machine using the GPIO pins directly. @item @b{at91rm9200} @* Like the EP93xx - but an ATMEL AT91RM9200 based solution using the GPIO pins on the chip. @end itemize @node Running @chapter Running @cindex running OpenOCD @cindex --configfile @cindex --debug_level @cindex --logfile @cindex --search The @option{--help} option shows: @verbatim bash$ openocd --help --help | -h display this help --version | -v display OpenOCD version --file | -f use configuration file --search | -s dir to search for config files and scripts --debug | -d set debug level <0-3> --log_output | -l redirect log output to file --command | -c run --pipe | -p use pipes when talking to gdb @end verbatim By default OpenOCD reads the file configuration file ``openocd.cfg'' in the current directory. To specify a different (or multiple) configuration file, you can use the ``-f'' option. For example: @example openocd -f config1.cfg -f config2.cfg -f config3.cfg @end example Once started, OpenOCD runs as a daemon, waiting for connections from clients (Telnet, GDB, Other). If you are having problems, you can enable internal debug messages via the ``-d'' option. Also it is possible to interleave commands w/config scripts using the @option{-c} command line switch. To enable debug output (when reporting problems or working on OpenOCD itself), use the @option{-d} command line switch. This sets the @option{debug_level} to "3", outputting the most information, including debug messages. The default setting is "2", outputting only informational messages, warnings and errors. You can also change this setting from within a telnet or gdb session using @option{debug_level } @xref{debug_level}. You can redirect all output from the daemon to a file using the @option{-l } switch. Search paths for config/script files can be added to OpenOCD by using the @option{-s } switch. The current directory and the OpenOCD target library is in the search path by default. For details on the @option{-p} option. @xref{Connecting to GDB}. Note! OpenOCD will launch the GDB & telnet server even if it can not establish a connection with the target. In general, it is possible for the JTAG controller to be unresponsive until the target is set up correctly via e.g. GDB monitor commands in a GDB init script. @node Simple Configuration Files @chapter Simple Configuration Files @cindex configuration @section Outline There are 4 basic ways of ``configurating'' OpenOCD to run, they are: @enumerate @item A small openocd.cfg file which ``sources'' other configuration files @item A monolithic openocd.cfg file @item Many -f filename options on the command line @item Your Mixed Solution @end enumerate @section Small configuration file method This is the preferred method. It is simple and works well for many people. The developers of OpenOCD would encourage you to use this method. If you create a new configuration please email new configurations to the development list. Here is an example of an openocd.cfg file for an ATMEL at91sam7x256 @example source [find interface/signalyzer.cfg] # GDB can also flash my flash! gdb_memory_map enable gdb_flash_program enable source [find target/sam7x256.cfg] @end example There are many example configuration scripts you can work with. You should look in the directory: @t{$(INSTALLDIR)/lib/openocd}. You should find: @enumerate @item @b{board} - eval board level configurations @item @b{interface} - specific dongle configurations @item @b{target} - the target chips @item @b{tcl} - helper scripts @item @b{xscale} - things specific to the xscale. @end enumerate Look first in the ``boards'' area, then the ``targets'' area. Often a board configuration is a good example to work from. @section Many -f filename options Some believe this is a wonderful solution, others find it painful. You can use a series of ``-f filename'' options on the command line, OpenOCD will read each filename in sequence, for example: @example openocd -f file1.cfg -f file2.cfg -f file2.cfg @end example You can also intermix various commands with the ``-c'' command line option. @section Monolithic file The ``Monolithic File'' dispenses with all ``source'' statements and puts everything in one self contained (monolithic) file. This is not encouraged. Please try to ``source'' various files or use the multiple -f technique. @section Advice for you Often, one uses a ``mixed approach''. Where possible, please try to ``source'' common things, and if needed cut/paste parts of the standard distribution configuration files as needed. @b{REMEMBER:} The ``important parts'' of your configuration file are: @enumerate @item @b{Interface} - Defines the dongle @item @b{Taps} - Defines the JTAG Taps @item @b{GDB Targets} - What GDB talks to @item @b{Flash Programing} - Very Helpful @end enumerate Some key things you should look at and understand are: @enumerate @item The reset configuration of your debug environment as a whole @item Is there a ``work area'' that OpenOCD can use? @* For ARM - work areas mean up to 10x faster downloads. @item For MMU/MPU based ARM chips (i.e.: ARM9 and later) will that work area still be available? @item For complex targets (multiple chips) the JTAG SPEED becomes an issue. @end enumerate @node Config File Guidelines @chapter Config File Guidelines This section/chapter is aimed at developers and integrators of OpenOCD. These are guidelines for creating new boards and new target configurations as of 28/Nov/2008. However, you, the user of OpenOCD, should be somewhat familiar with this section as it should help explain some of the internals of what you might be looking at. The user should find the following directories under @t{$(INSTALLDIR)/lib/openocd} : @itemize @bullet @item @b{interface} @*Think JTAG Dongle. Files that configure the JTAG dongle go here. @item @b{board} @* Think Circuit Board, PWA, PCB, they go by many names. Board files contain initialization items that are specific to a board - for example: The SDRAM initialization sequence for the board, or the type of external flash and what address it is found at. Any initialization sequence to enable that external flash or SDRAM should be found in the board file. Boards may also contain multiple targets, i.e.: Two CPUs, or a CPU and an FPGA or CPLD. @item @b{target} @* Think chip. The ``target'' directory represents a JTAG tap (or chip) OpenOCD should control, not a board. Two common types of targets are ARM chips and FPGA or CPLD chips. @end itemize @b{If needed...} The user in their ``openocd.cfg'' file or the board file might override a specific feature in any of the above files by setting a variable or two before sourcing the target file. Or adding various commands specific to their situation. @section Interface Config Files The user should be able to source one of these files via a command like this: @example source [find interface/FOOBAR.cfg] Or: openocd -f interface/FOOBAR.cfg @end example A preconfigured interface file should exist for every interface in use today, that said, perhaps some interfaces have only been used by the sole developer who created it. Interface files should be found in @t{$(INSTALLDIR)/lib/openocd/interface} @section Board Config Files @b{Note: BOARD directory NEW as of 28/nov/2008} The user should be able to source one of these files via a command like this: @example source [find board/FOOBAR.cfg] Or: openocd -f board/FOOBAR.cfg @end example The board file should contain one or more @t{source [find target/FOO.cfg]} statements along with any board specific things. In summary the board files should contain (if present) @enumerate @item External flash configuration (i.e.: NOR flash on CS0, two NANDs on CS2) @item SDRAM configuration (size, speed, etc. @item Board specific IO configuration (i.e.: GPIO pins might disable a 2nd flash) @item Multiple TARGET source statements @item All things that are not ``inside a chip'' @item Things inside a chip go in a 'target' file @end enumerate @section Target Config Files The user should be able to source one of these files via a command like this: @example source [find target/FOOBAR.cfg] Or: openocd -f target/FOOBAR.cfg @end example In summary the target files should contain @enumerate @item Set defaults @item Create taps @item Reset configuration @item Work areas @item CPU/Chip/CPU-Core specific features @item On-Chip flash @end enumerate @subsection Important variable names By default, the end user should never need to set these variables. However, if the user needs to override a setting they only need to set the variable in a simple way. @itemize @bullet @item @b{CHIPNAME} @* This gives a name to the overall chip, and is used as part of the tap identifier dotted name. @item @b{ENDIAN} @* By default little - unless the chip or board is not normally used that way. @item @b{CPUTAPID} @* When OpenOCD examines the JTAG chain, it will attempt to identify every chip. If the @t{-expected-id} is nonzero, OpenOCD attempts to verify the tap id number verses configuration file and may issue an error or warning like this. The hope is that this will help to pinpoint problems in OpenOCD configurations. @example Info: JTAG tap: sam7x256.cpu tap/device found: 0x3f0f0f0f (Manufacturer: 0x787, Part: 0xf0f0, Version: 0x3) Error: ERROR: Tap: sam7x256.cpu - Expected id: 0x12345678, Got: 0x3f0f0f0f Error: ERROR: expected: mfg: 0x33c, part: 0x2345, ver: 0x1 Error: ERROR: got: mfg: 0x787, part: 0xf0f0, ver: 0x3 @end example @item @b{_TARGETNAME} @* By convention, this variable is created by the target configuration script. The board configuration file may make use of this variable to configure things like a ``reset init'' script, or other things specific to that board and that target. If the chip has 2 targets, use the names @b{_TARGETNAME0}, @b{_TARGETNAME1}, ... etc. @b{Remember:} The ``board file'' may include multiple targets. At no time should the name ``target0'' (the default target name if none was specified) be used. The name ``target0'' is a hard coded name - the next target on the board will be some other number. In the same way, avoid using target numbers even when they are permitted; use the right target name(s) for your board. The user (or board file) should reasonably be able to: @example source [find target/FOO.cfg] $_TARGETNAME configure ... FOO specific parameters source [find target/BAR.cfg] $_TARGETNAME configure ... BAR specific parameters @end example @end itemize @subsection Tcl Variables Guide Line The Full Tcl/Tk language supports ``namespaces'' - JIM-Tcl does not. Thus the rule we follow in OpenOCD is this: Variables that begin with a leading underscore are temporary in nature, and can be modified and used at will within a ?TARGET? configuration file. @b{EXAMPLE:} The user should be able to do this: @example # Board has 3 chips, # PXA270 #1 network side, big endian # PXA270 #2 video side, little endian # Xilinx Glue logic set CHIPNAME network set ENDIAN big source [find target/pxa270.cfg] # variable: _TARGETNAME = network.cpu # other commands can refer to the "network.cpu" tap. $_TARGETNAME configure .... params for this CPU.. set ENDIAN little set CHIPNAME video source [find target/pxa270.cfg] # variable: _TARGETNAME = video.cpu # other commands can refer to the "video.cpu" tap. $_TARGETNAME configure .... params for this CPU.. unset ENDIAN set CHIPNAME xilinx source [find target/spartan3.cfg] # Since $_TARGETNAME is temporal.. # these names still work! network.cpu configure ... params video.cpu configure ... params @end example @subsection Default Value Boiler Plate Code All target configuration files should start with this (or a modified form) @example # SIMPLE example if @{ [info exists CHIPNAME] @} @{ set _CHIPNAME $CHIPNAME @} else @{ set _CHIPNAME sam7x256 @} if @{ [info exists ENDIAN] @} @{ set _ENDIAN $ENDIAN @} else @{ set _ENDIAN little @} if @{ [info exists CPUTAPID ] @} @{ set _CPUTAPID $CPUTAPID @} else @{ set _CPUTAPID 0x3f0f0f0f @} @end example @subsection Creating Taps After the ``defaults'' are choosen [see above] the taps are created. @b{SIMPLE example:} such as an Atmel AT91SAM7X256 @example # for an ARM7TDMI. set _TARGETNAME [format "%s.cpu" $_CHIPNAME] jtag newtap $_CHIPNAME cpu -irlen 4 -ircapture 0x1 -irmask 0xf \ -expected-id $_CPUTAPID @end example @b{COMPLEX example:} This is an SNIP/example for an STR912 - which has 3 internal taps. Key features shown: @enumerate @item @b{Unform tap names} - See: Tap Naming Convention @item @b{_TARGETNAME} is created at the end where used. @end enumerate @example if @{ [info exists FLASHTAPID ] @} @{ set _FLASHTAPID $FLASHTAPID @} else @{ set _FLASHTAPID 0x25966041 @} jtag newtap $_CHIPNAME flash -irlen 8 -ircapture 0x1 -irmask 0x1 \ -expected-id $_FLASHTAPID if @{ [info exists CPUTAPID ] @} @{ set _CPUTAPID $CPUTAPID @} else @{ set _CPUTAPID 0x25966041 @} jtag newtap $_CHIPNAME cpu -irlen 4 -ircapture 0xf -irmask 0xe \ -expected-id $_CPUTAPID if @{ [info exists BSTAPID ] @} @{ set _BSTAPID $BSTAPID @} else @{ set _BSTAPID 0x1457f041 @} jtag newtap $_CHIPNAME bs -irlen 5 -ircapture 0x1 -irmask 0x1 \ -expected-id $_BSTAPID set _TARGETNAME [format "%s.cpu" $_CHIPNAME] @end example @b{Tap Naming Convention} See the command ``jtag newtap'' for detail, but in brief the names you should use are: @itemize @bullet @item @b{tap} @item @b{cpu} @item @b{flash} @item @b{bs} @item @b{etb} @item @b{jrc} @item @b{unknownN} - it happens :-( @end itemize @subsection Reset Configuration Some chips have specific ways the TRST and SRST signals are managed. If these are @b{CHIP SPECIFIC} they go here, if they are @b{BOARD SPECIFIC} they go in the board file. @subsection Work Areas Work areas are small RAM areas used by OpenOCD to speed up downloads, and to download small snippets of code to program flash chips. If the chip includes a form of ``on-chip-ram'' - and many do - define a reasonable work area and use the ``backup'' option. @b{PROBLEMS:} On more complex chips, this ``work area'' may become inaccessible if/when the application code enables or disables the MMU. @subsection ARM Core Specific Hacks If the chip has a DCC, enable it. If the chip is an ARM9 with some special high speed download features - enable it. If the chip has an ARM ``vector catch'' feature - by default enable it for Undefined Instructions, Data Abort, and Prefetch Abort, if the user is really writing a handler for those situations - they can easily disable it. Experiance has shown the ``vector catch'' is helpful - for common programing errors. If present, the MMU, the MPU and the CACHE should be disabled. Some ARM cores are equipped with trace support, which permits examination of the instruction and data bus activity. Trace activity is controlled through an ``Embedded Trace Module'' (ETM) on one of the core's scan chains. The ETM emits voluminous data through a ``trace port''. (@xref{ARM Tracing}.) If you are using an external trace port, configure it in your board config file. If you are using an on-chip ``Embedded Trace Buffer'' (ETB), configure it in your target config file. @example etm config $_TARGETNAME 16 normal full etb etb config $_TARGETNAME $_CHIPNAME.etb @end example @subsection Internal Flash Configuration This applies @b{ONLY TO MICROCONTROLLERS} that have flash built in. @b{Never ever} in the ``target configuration file'' define any type of flash that is external to the chip. (For example a BOOT flash on Chip Select 0.) Such flash information goes in a board file - not the TARGET (chip) file. Examples: @itemize @bullet @item at91sam7x256 - has 256K flash YES enable it. @item str912 - has flash internal YES enable it. @item imx27 - uses boot flash on CS0 - it goes in the board file. @item pxa270 - again - CS0 flash - it goes in the board file. @end itemize @node About JIM-Tcl @chapter About JIM-Tcl @cindex JIM Tcl @cindex tcl OpenOCD includes a small ``TCL Interpreter'' known as JIM-TCL. You can learn more about JIM here: @url{http://jim.berlios.de} @itemize @bullet @item @b{JIM vs. Tcl} @* JIM-TCL is a stripped down version of the well known Tcl language, which can be found here: @url{http://www.tcl.tk}. JIM-Tcl has far fewer features. JIM-Tcl is a single .C file and a single .H file and impliments the basic Tcl command set along. In contrast: Tcl 8.6 is a 4.2 MB .zip file containing 1540 files. @item @b{Missing Features} @* Our practice has been: Add/clone the real Tcl feature if/when needed. We welcome JIM Tcl improvements, not bloat. @item @b{Scripts} @* OpenOCD configuration scripts are JIM Tcl Scripts. OpenOCD's command interpreter today (28/nov/2008) is a mixture of (newer) JIM-Tcl commands, and (older) the orginal command interpreter. @item @b{Commands} @* At the OpenOCD telnet command line (or via the GDB mon command) one can type a Tcl for() loop, set variables, etc. @item @b{Historical Note} @* JIM-Tcl was introduced to OpenOCD in spring 2008. @item @b{Need a crash course in Tcl?} @*@xref{Tcl Crash Course}. @end itemize @node Daemon Configuration @chapter Daemon Configuration @cindex initialization The commands here are commonly found in the openocd.cfg file and are used to specify what TCP/IP ports are used, and how GDB should be supported. @section Configuration Stage @cindex configuration stage @cindex configuration command When the OpenOCD server process starts up, it enters a @emph{configuration stage} which is the only time that certain commands, @emph{configuration commands}, may be issued. Those configuration commands include declaration of TAPs and other basic setup. The server must leave the configuration stage before it may access or activate TAPs. After it leaves this stage, configuration commands may no longer be issued. @deffn {Config Command} init This command terminates the configuration stage and enters the normal command mode. This can be useful to add commands to the startup scripts and commands such as resetting the target, programming flash, etc. To reset the CPU upon startup, add "init" and "reset" at the end of the config script or at the end of the OpenOCD command line using the @option{-c} command line switch. If this command does not appear in any startup/configuration file OpenOCD executes the command for you after processing all configuration files and/or command line options. @b{NOTE:} This command normally occurs at or near the end of your openocd.cfg file to force OpenOCD to ``initialize'' and make the targets ready. For example: If your openocd.cfg file needs to read/write memory on your target, @command{init} must occur before the memory read/write commands. This includes @command{nand probe}. @end deffn @section TCP/IP Ports @cindex TCP port @cindex server @cindex port The OpenOCD server accepts remote commands in several syntaxes. Each syntax uses a different TCP/IP port, which you may specify only during configuration (before those ports are opened). @deffn {Command} gdb_port (number) @cindex GDB server Specify or query the first port used for incoming GDB connections. The GDB port for the first target will be gdb_port, the second target will listen on gdb_port + 1, and so on. When not specified during the configuration stage, the port @var{number} defaults to 3333. @end deffn @deffn {Command} tcl_port (number) Specify or query the port used for a simplified RPC connection that can be used by clients to issue TCL commands and get the output from the Tcl engine. Intended as a machine interface. When not specified during the configuration stage, the port @var{number} defaults to 6666. @end deffn @deffn {Command} telnet_port (number) Specify or query the port on which to listen for incoming telnet connections. This port is intended for interaction with one human through TCL commands. When not specified during the configuration stage, the port @var{number} defaults to 4444. @end deffn @anchor{GDB Configuration} @section GDB Configuration @cindex GDB @cindex GDB configuration You can reconfigure some GDB behaviors if needed. The ones listed here are static and global. @xref{Target Create}, about declaring individual targets. @xref{Target Events}, about configuring target-specific event handling. @anchor{gdb_breakpoint_override} @deffn {Command} gdb_breakpoint_override Force breakpoint type for gdb @command{break} commands. The raison d'etre for this option is to support GDB GUI's which don't distinguish hard versus soft breakpoints, if the default OpenOCD and GDB behaviour is not sufficient. GDB normally uses hardware breakpoints if the memory map has been set up for flash regions. This option replaces older arm7_9 target commands that addressed the same issue. @end deffn @deffn {Config command} gdb_detach Configures what OpenOCD will do when GDB detaches from the daemon. Default behaviour is @var{resume}. @end deffn @anchor{gdb_flash_program} @deffn {Config command} gdb_flash_program Set to @var{enable} to cause OpenOCD to program the flash memory when a vFlash packet is received. The default behaviour is @var{enable}. @end deffn @deffn {Config command} gdb_memory_map Set to @var{enable} to cause OpenOCD to send the memory configuration to GDB when requested. GDB will then know when to set hardware breakpoints, and program flash using the GDB load command. @command{gdb_flash_program enable} must also be enabled for flash programming to work. Default behaviour is @var{enable}. @xref{gdb_flash_program}. @end deffn @deffn {Config command} gdb_report_data_abort Specifies whether data aborts cause an error to be reported by GDB memory read packets. The default behaviour is @var{disable}; use @var{enable} see these errors reported. @end deffn @node Interface - Dongle Configuration @chapter Interface - Dongle Configuration Interface commands are normally found in an interface configuration file which is sourced by your openocd.cfg file. These commands tell OpenOCD what type of JTAG dongle you have and how to talk to it. @section Simple Complete Interface Examples @b{A Turtelizer FT2232 Based JTAG Dongle} @verbatim #interface interface ft2232 ft2232_device_desc "Turtelizer JTAG/RS232 Adapter A" ft2232_layout turtelizer2 ft2232_vid_pid 0x0403 0xbdc8 @end verbatim @b{A SEGGER Jlink} @verbatim # jlink interface interface jlink @end verbatim @b{A Raisonance RLink} @verbatim # rlink interface interface rlink @end verbatim @b{Parallel Port} @verbatim interface parport parport_port 0xc8b8 parport_cable wiggler jtag_speed 0 @end verbatim @b{ARM-JTAG-EW} @verbatim interface arm-jtag-ew @end verbatim @section Interface Command The interface command tells OpenOCD what type of JTAG dongle you are using. Depending on the type of dongle, you may need to have one or more additional commands. @itemize @bullet @item @b{interface} <@var{name}> @cindex interface @*Use the interface driver <@var{name}> to connect to the target. Currently supported interfaces are @itemize @minus @item @b{parport} @* PC parallel port bit-banging (Wigglers, PLD download cable, ...) @item @b{amt_jtagaccel} @* Amontec Chameleon in its JTAG Accelerator configuration connected to a PC's EPP mode parallel port @item @b{ft2232} @* FTDI FT2232 (USB) based devices using either the open-source libftdi or the binary only FTD2XX driver. The FTD2XX is superior in performance, but not available on every platform. The libftdi uses libusb, and should be portable to all systems that provide libusb. @item @b{ep93xx} @*Cirrus Logic EP93xx based single-board computer bit-banging (in development) @item @b{presto} @* ASIX PRESTO USB JTAG programmer. @item @b{usbprog} @* usbprog is a freely programmable USB adapter. @item @b{gw16012} @* Gateworks GW16012 JTAG programmer. @item @b{jlink} @* Segger jlink USB adapter @item @b{rlink} @* Raisonance RLink USB adapter @item @b{vsllink} @* vsllink is part of Versaloon which is a versatile USB programmer. @item @b{arm-jtag-ew} @* Olimex ARM-JTAG-EW USB adapter @comment - End parameters @end itemize @comment - End Interface @end itemize @subsection parport options @itemize @bullet @item @b{parport_port} <@var{number}> @cindex parport_port @*Either the address of the I/O port (default: 0x378 for LPT1) or the number of the @file{/dev/parport} device When using PPDEV to access the parallel port, use the number of the parallel port: @option{parport_port 0} (the default). If @option{parport_port 0x378} is specified you may encounter a problem. @item @b{parport_cable} <@var{name}> @cindex parport_cable @*The layout of the parallel port cable used to connect to the target. Currently supported cables are @itemize @minus @item @b{wiggler} @cindex wiggler The original Wiggler layout, also supported by several clones, such as the Olimex ARM-JTAG @item @b{wiggler2} @cindex wiggler2 Same as original wiggler except an led is fitted on D5. @item @b{wiggler_ntrst_inverted} @cindex wiggler_ntrst_inverted Same as original wiggler except TRST is inverted. @item @b{old_amt_wiggler} @cindex old_amt_wiggler The Wiggler configuration that comes with Amontec's Chameleon Programmer. The new version available from the website uses the original Wiggler layout ('@var{wiggler}') @item @b{chameleon} @cindex chameleon The Amontec Chameleon's CPLD when operated in configuration mode. This is only used to program the Chameleon itself, not a connected target. @item @b{dlc5} @cindex dlc5 The Xilinx Parallel cable III. @item @b{triton} @cindex triton The parallel port adapter found on the 'Karo Triton 1 Development Board'. This is also the layout used by the HollyGates design (see @uref{http://www.lartmaker.nl/projects/jtag/}). @item @b{flashlink} @cindex flashlink The ST Parallel cable. @item @b{arm-jtag} @cindex arm-jtag Same as original wiggler except SRST and TRST connections reversed and TRST is also inverted. @item @b{altium} @cindex altium Altium Universal JTAG cable. @end itemize @item @b{parport_write_on_exit} <@var{on}|@var{off}> @cindex parport_write_on_exit @*This will configure the parallel driver to write a known value to the parallel interface on exiting OpenOCD @end itemize @subsection amt_jtagaccel options @itemize @bullet @item @b{parport_port} <@var{number}> @cindex parport_port @*Either the address of the I/O port (default: 0x378 for LPT1) or the number of the @file{/dev/parport} device @end itemize @subsection ft2232 options @itemize @bullet @item @b{ft2232_device_desc} <@var{description}> @cindex ft2232_device_desc @*The USB device description of the FTDI FT2232 device. If not specified, the FTDI default value is used. This setting is only valid if compiled with FTD2XX support. @b{TODO:} Confirm the following: On Windows the name needs to end with a ``space A''? Or not? It has to do with the FTD2xx driver. When must this be added and when must it not be added? Why can't the code in the interface or in OpenOCD automatically add this if needed? -- Duane. @item @b{ft2232_serial} <@var{serial-number}> @cindex ft2232_serial @*The serial number of the FTDI FT2232 device. If not specified, the FTDI default values are used. @item @b{ft2232_layout} <@var{name}> @cindex ft2232_layout @*The layout of the FT2232 GPIO signals used to control output-enables and reset signals. Valid layouts are @itemize @minus @item @b{usbjtag} "USBJTAG-1" layout described in the original OpenOCD diploma thesis @item @b{jtagkey} Amontec JTAGkey and JTAGkey-Tiny @item @b{signalyzer} Signalyzer @item @b{olimex-jtag} Olimex ARM-USB-OCD @item @b{m5960} American Microsystems M5960 @item @b{evb_lm3s811} Luminary Micro EVB_LM3S811 as a JTAG interface (not onboard processor), no TRST or SRST signals on external connector @item @b{comstick} Hitex STR9 comstick @item @b{stm32stick} Hitex STM32 Performance Stick @item @b{flyswatter} Tin Can Tools Flyswatter @item @b{turtelizer2} egnite Software turtelizer2 @item @b{oocdlink} OOCDLink @item @b{axm0432_jtag} Axiom AXM-0432 @item @b{cortino} Hitex Cortino JTAG interface @end itemize @item @b{ft2232_vid_pid} <@var{vid}> <@var{pid}> @*The vendor ID and product ID of the FTDI FT2232 device. If not specified, the FTDI default values are used. Multiple <@var{vid}>, <@var{pid}> pairs may be given, e.g. @example ft2232_vid_pid 0x0403 0xcff8 0x15ba 0x0003 @end example @item @b{ft2232_latency} <@var{ms}> @*On some systems using FT2232 based JTAG interfaces the FT_Read function call in ft2232_read() fails to return the expected number of bytes. This can be caused by USB communication delays and has proved hard to reproduce and debug. Setting the FT2232 latency timer to a larger value increases delays for short USB packets but it also reduces the risk of timeouts before receiving the expected number of bytes. The OpenOCD default value is 2 and for some systems a value of 10 has proved useful. @end itemize @subsection ep93xx options @cindex ep93xx options Currently, there are no options available for the ep93xx interface. @anchor{JTAG Speed} @section JTAG Speed JTAG clock setup is part of system setup. It @emph{does not belong with interface setup} since any interface only knows a few of the constraints for the JTAG clock speed. Sometimes the JTAG speed is changed during the target initialization process: (1) slow at reset, (2) program the CPU clocks, (3) run fast. Both the "slow" and "fast" clock rates are functions of the oscillators used, the chip, the board design, and sometimes power management software that may be active. The speed used during reset can be adjusted using pre_reset and post_reset event handlers. @xref{Target Events}. If your system supports adaptive clocking (RTCK), configuring JTAG to use that is probably the most robust approach. However, it introduces delays to synchronize clocks; so it may not be the fastest solution. @b{NOTE:} Script writers should consider using @command{jtag_rclk} instead of @command{jtag_khz}. @deffn {Command} jtag_khz max_speed_kHz A non-zero speed is in KHZ. Hence: 3000 is 3mhz. JTAG interfaces usually support a limited number of speeds. The speed actually used won't be faster than the speed specified. As a rule of thumb, if you specify a clock rate make sure the JTAG clock is no more than @math{1/6th CPU-Clock}. This is especially true for synthesized cores (ARMxxx-S). Speed 0 (khz) selects RTCK method. @xref{FAQ RTCK}. If your system uses RTCK, you won't need to change the JTAG clocking after setup. Not all interfaces, boards, or targets support ``rtck''. If the interface device can not support it, an error is returned when you try to use RTCK. @end deffn @defun jtag_rclk fallback_speed_kHz @cindex RTCK This Tcl proc (defined in startup.tcl) attempts to enable RTCK/RCLK. If that fails (maybe the interface, board, or target doesn't support it), falls back to the specified frequency. @example # Fall back to 3mhz if RTCK is not supported jtag_rclk 3000 @end example @end defun @node Reset Configuration @chapter Reset Configuration @cindex Reset Configuration Every system configuration may require a different reset configuration. This can also be quite confusing. Resets also interact with @var{reset-init} event handlers, which do things like setting up clocks and DRAM, and JTAG clock rates. (@xref{JTAG Speed}.) Please see the various board files for examples. @quotation Note To maintainers and integrators: Reset configuration touches several things at once. Normally the board configuration file should define it and assume that the JTAG adapter supports everything that's wired up to the board's JTAG connector. However, the target configuration file could also make note of something the silicon vendor has done inside the chip, which will be true for most (or all) boards using that chip. And when the JTAG adapter doesn't support everything, the system configuration file will need to override parts of the reset configuration provided by other files. @end quotation @section Types of Reset There are many kinds of reset possible through JTAG, but they may not all work with a given board and adapter. That's part of why reset configuration can be error prone. @itemize @bullet @item @emph{System Reset} ... the @emph{SRST} hardware signal resets all chips connected to the JTAG adapter, such as processors, power management chips, and I/O controllers. Normally resets triggered with this signal behave exactly like pressing a RESET button. @item @emph{JTAG TAP Reset} ... the @emph{TRST} hardware signal resets just the TAP controllers connected to the JTAG adapter. Such resets should not be visible to the rest of the system; resetting a device's the TAP controller just puts that controller into a known state. @item @emph{Emulation Reset} ... many devices can be reset through JTAG commands. These resets are often distinguishable from system resets, either explicitly (a "reset reason" register says so) or implicitly (not all parts of the chip get reset). @item @emph{Other Resets} ... system-on-chip devices often support several other types of reset. You may need to arrange that a watchdog timer stops while debugging, preventing a watchdog reset. There may be individual module resets. @end itemize In the best case, OpenOCD can hold SRST, then reset the TAPs via TRST and send commands through JTAG to halt the CPU at the reset vector before the 1st instruction is executed. Then when it finally releases the SRST signal, the system is halted under debugger control before any code has executed. This is the behavior required to support the @command{reset halt} and @command{reset init} commands; after @command{reset init} a board-specific script might do things like setting up DRAM. (@xref{Reset Command}.) @section SRST and TRST Signal Issues Because SRST and TRST are hardware signals, they can have a variety of system-specific constraints. Some of the most common issues are: @itemize @bullet @item @emph{Signal not available} ... Some boards don't wire SRST or TRST to the JTAG connector. Some JTAG adapters don't support such signals even if they are wired up. Use the @command{reset_config} @var{signals} options to say when one of those signals is not connected. When SRST is not available, your code might not be able to rely on controllers having been fully reset during code startup. @item @emph{Signals shorted} ... Sometimes a chip, board, or adapter will connect SRST to TRST, instead of keeping them separate. Use the @command{reset_config} @var{combination} options to say when those signals aren't properly independent. @item @emph{Timing} ... Reset circuitry like a resistor/capacitor delay circuit, reset supervisor, or on-chip features can extend the effect of a JTAG adapter's reset for some time after the adapter stops issuing the reset. For example, there may be chip or board requirements that all reset pulses last for at least a certain amount of time; and reset buttons commonly have hardware debouncing. Use the @command{jtag_nsrst_delay} and @command{jtag_ntrst_delay} commands to say when extra delays are needed. @item @emph{Drive type} ... Reset lines often have a pullup resistor, letting the JTAG interface treat them as open-drain signals. But that's not a requirement, so the adapter may need to use push/pull output drivers. Also, with weak pullups it may be advisable to drive signals to both levels (push/pull) to minimize rise times. Use the @command{reset_config} @var{trst_type} and @var{srst_type} parameters to say how to drive reset signals. @end itemize There can also be other issues. Some devices don't fully conform to the JTAG specifications. Trivial system-specific differences are common, such as SRST and TRST using slightly different names. There are also vendors who distribute key JTAG documentation for their chips only to developers who have signed a Non-Disclosure Agreement (NDA). Sometimes there are chip-specific extensions like a requirement to use the normally-optional TRST signal (precluding use of JTAG adapters which don't pass TRST through), or needing extra steps to complete a TAP reset. In short, SRST and especially TRST handling may be very finicky, needing to cope with both architecture and board specific constraints. @section Commands for Handling Resets @deffn {Command} jtag_nsrst_delay milliseconds How long (in milliseconds) OpenOCD should wait after deasserting nSRST (active-low system reset) before starting new JTAG operations. When a board has a reset button connected to SRST line it will probably have hardware debouncing, implying you should use this. @end deffn @deffn {Command} jtag_ntrst_delay milliseconds How long (in milliseconds) OpenOCD should wait after deasserting nTRST (active-low JTAG TAP reset) before starting new JTAG operations. @end deffn @deffn {Command} reset_config mode_flag ... This command tells OpenOCD the reset configuration of your combination of JTAG board and target in target configuration scripts. If you have an interface that does not support SRST and TRST(unlikely), then you may be able to work around that problem by using a reset_config command to override any settings in the target configuration script. SRST and TRST has a fairly well understood definition and behaviour in the JTAG specification, but vendors take liberties to achieve various more or less clearly understood goals. Sometimes documentation is available, other times it is not. OpenOCD has the reset_config command to allow OpenOCD to deal with the various common cases. The @var{mode_flag} options can be specified in any order, but only one of each type -- @var{signals}, @var{combination}, @var{trst_type}, and @var{srst_type} -- may be specified at a time. If you don't provide a new value for a given type, its previous value (perhaps the default) is unchanged. For example, this means that you don't need to say anything at all about TRST just to declare that if the JTAG adapter should want to drive SRST, it must explicitly be driven high (@option{srst_push_pull}). @var{signals} can specify which of the reset signals are connected. For example, If the JTAG interface provides SRST, but the board doesn't connect that signal properly, then OpenOCD can't use it. Possible values are @option{none} (the default), @option{trst_only}, @option{srst_only} and @option{trst_and_srst}. @quotation Tip If your board provides SRST or TRST through the JTAG connector, you must declare that or else those signals will not be used. @end quotation The @var{combination} is an optional value specifying broken reset signal implementations. The default behaviour if no option given is @option{separate}, indicating everything behaves normally. @option{srst_pulls_trst} states that the test logic is reset together with the reset of the system (e.g. Philips LPC2000, "broken" board layout), @option{trst_pulls_srst} says that the system is reset together with the test logic (only hypothetical, I haven't seen hardware with such a bug, and can be worked around). @option{combined} implies both @option{srst_pulls_trst} and @option{trst_pulls_srst}. The optional @var{trst_type} and @var{srst_type} parameters allow the driver mode of each reset line to be specified. These values only affect JTAG interfaces with support for different driver modes, like the Amontec JTAGkey and JTAGAccelerator. Also, they are necessarily ignored if the relevant signal (TRST or SRST) is not connected. Possible @var{trst_type} driver modes for the test reset signal (TRST) are @option{trst_push_pull} (default) and @option{trst_open_drain}. Most boards connect this signal to a pulldown, so the JTAG TAPs never leave reset unless they are hooked up to a JTAG adapter. Possible @var{srst_type} driver modes for the system reset signal (SRST) are the default @option{srst_open_drain}, and @option{srst_push_pull}. Most boards connect this signal to a pullup, and allow the signal to be pulled low by various events including system powerup and pressing a reset button. @end deffn @node Tap Creation @chapter Tap Creation @cindex tap creation @cindex tap configuration In order for OpenOCD to control a target, a JTAG tap must be defined/created. Commands to create taps are normally found in a configuration file and are not normally typed by a human. When a tap is created a @b{dotted.name} is created for the tap. Other commands use that dotted.name to manipulate or refer to the tap. Tap Uses: @itemize @bullet @item @b{Debug Target} A tap can be used by a GDB debug target @item @b{Flash Programing} Some chips program the flash directly via JTAG, instead of indirectly by making a CPU do it. @item @b{Boundry Scan} Some chips support boundary scan. @end itemize @anchor{jtag newtap} @section jtag newtap @b{@t{jtag newtap CHIPNAME TAPNAME configparams ....}} @cindex jtag newtap @cindex tap @cindex tap order @cindex tap geometry @comment START options @itemize @bullet @item @b{CHIPNAME} @* is a symbolic name of the chip. @item @b{TAPNAME} @* is a symbol name of a tap present on the chip. @item @b{Required configparams} @* Every tap has 3 required configparams, and several ``optional parameters'', the required parameters are: @comment START REQUIRED @itemize @bullet @item @b{-irlen NUMBER} - the length in bits of the instruction register, mostly 4 or 5 bits. @item @b{-ircapture NUMBER} - the IDCODE capture command, usually 0x01. @item @b{-irmask NUMBER} - the corresponding mask for the IR register. For some devices, there are bits in the IR that aren't used. This lets you mask them off when doing comparisons. In general, this should just be all ones for the size of the IR. @comment END REQUIRED @end itemize An example of a FOOBAR Tap @example jtag newtap foobar tap -irlen 7 -ircapture 0x42 -irmask 0x55 @end example Creates the tap ``foobar.tap'' with the instruction register (IR) is 7 bits long, during Capture-IR 0x42 is loaded into the IR, and bits [6,4,2,0] are checked. @item @b{Optional configparams} @comment START Optional @itemize @bullet @item @b{-expected-id NUMBER} @* By default it is zero. If non-zero represents the expected tap ID used when the JTAG chain is examined. Repeat the option as many times as required if multiple id's can be expected. See below. @item @b{-disable} @item @b{-enable} @* By default not specified the tap is enabled. Some chips have a JTAG route controller (JRC) that is used to enable and/or disable specific JTAG taps. You can later enable or disable any JTAG tap via the command @b{jtag tapenable DOTTED.NAME} or @b{jtag tapdisable DOTTED.NAME} @comment END Optional @end itemize @comment END OPTIONS @end itemize @b{Notes:} @comment START NOTES @itemize @bullet @item @b{Technically} @* newtap is a sub command of the ``jtag'' command @item @b{Big Picture Background} @*GDB Talks to OpenOCD using the GDB protocol via TCP/IP. OpenOCD then uses the JTAG interface (the dongle) to control the JTAG chain on your board. Your board has one or more chips in a @i{daisy chain configuration}. Each chip may have one or more JTAG taps. GDB ends up talking via OpenOCD to one of the taps. @item @b{NAME Rules} @*Names follow ``C'' symbol name rules (start with alpha ...) @item @b{TAPNAME - Conventions} @itemize @bullet @item @b{tap} - should be used only FPGA or CPLD like devices with a single tap. @item @b{cpu} - the main CPU of the chip, alternatively @b{foo.arm} and @b{foo.dsp} @item @b{flash} - if the chip has a flash tap, example: str912.flash @item @b{bs} - for boundary scan if this is a seperate tap. @item @b{etb} - for an embedded trace buffer (example: an ARM ETB11) @item @b{jrc} - for JTAG route controller (example: OMAP3530 found on Beagleboards) @item @b{unknownN} - where N is a number if you have no idea what the tap is for @item @b{Other names} - Freescale IMX31 has a SDMA (smart dma) with a JTAG tap, that tap should be called the ``sdma'' tap. @item @b{When in doubt} - use the chip maker's name in their data sheet. @end itemize @item @b{DOTTED.NAME} @* @b{CHIPNAME}.@b{TAPNAME} creates the tap name, aka: the @b{Dotted.Name} is the @b{CHIPNAME} and @b{TAPNAME} combined with a dot (period); for example: @b{xilinx.tap}, @b{str912.flash}, @b{omap3530.jrc}, or @b{stm32.cpu} The @b{dotted.name} is used in numerous other places to refer to various taps. @item @b{ORDER} @* The order this command appears via the config files is important. @item @b{Multi Tap Example} @* This example is based on the ST Microsystems STR912. See the ST document titled: @b{STR91xFAxxx, Section 3.15 Jtag Interface, Page: 28/102, Figure 3: JTAG chaining inside the STR91xFA}. @url{http://eu.st.com/stonline/products/literature/ds/13495.pdf} @*@b{checked: 28/nov/2008} The diagram shows that the TDO pin connects to the flash tap, flash TDI connects to the CPU debug tap, CPU TDI connects to the boundary scan tap which then connects to the TDI pin. @example # The order is... # create tap: 'str912.flash' jtag newtap str912 flash ... params ... # create tap: 'str912.cpu' jtag newtap str912 cpu ... params ... # create tap: 'str912.bs' jtag newtap str912 bs ... params ... @end example @item @b{Note: Deprecated} - Index Numbers @* Prior to 28/nov/2008, JTAG taps where numbered from 0..N this feature is still present, however its use is highly discouraged and should not be counted upon. Update all of your scripts to use TAP names rather than numbers. @item @b{Multiple chips} @* If your board has multiple chips, you should be able to @b{source} two configuration files, in the proper order, and have the taps created in the proper order. @comment END NOTES @end itemize @comment at command level @section Enable/Disable Taps @b{Note:} These commands are intended to be used as a machine/script interface. Humans might find the ``scan_chain'' command more helpful when querying the state of the JTAG taps. @b{By default, all taps are enabled} @itemize @bullet @item @b{jtag tapenable} @var{DOTTED.NAME} @item @b{jtag tapdisable} @var{DOTTED.NAME} @item @b{jtag tapisenabled} @var{DOTTED.NAME} @end itemize @cindex tap enable @cindex tap disable @cindex JRC @cindex route controller These commands are used when your target has a JTAG route controller that effectively adds or removes a tap from the JTAG chain in a non-standard way. The ``standard way'' to remove a tap would be to place the tap in bypass mode. But with the advent of modern chips, this is not always a good solution. Some taps operate slowly, others operate fast, and there are other JTAG clock synchronisation problems one must face. To solve that problem, the JTAG route controller was introduced. Rather than ``bypass'' the tap, the tap is completely removed from the circuit and skipped. From OpenOCD's point of view, a JTAG tap is in one of 3 states: @itemize @bullet @item @b{Enabled - Not In ByPass} and has a variable bit length @item @b{Enabled - In ByPass} and has a length of exactly 1 bit. @item @b{Disabled} and has a length of ZERO and is removed from the circuit. @end itemize The IEEE JTAG definition has no concept of a ``disabled'' tap. @b{Historical note:} this feature was added 28/nov/2008 @b{jtag tapisenabled DOTTED.NAME} This command returns 1 if the named tap is currently enabled, 0 if not. This command exists so that scripts that manipulate a JRC (like the OMAP3530 has) can determine if OpenOCD thinks a tap is presently enabled or disabled. @page @node Target Configuration @chapter Target Configuration @cindex GDB target This chapter discusses how to create a GDB debug target. Before creating a ``target'' a JTAG tap DOTTED.NAME must exist first. @section targets [NAME] @b{Note:} This command name is PLURAL - not singular. With NO parameter, this plural @b{targets} command lists all known targets in a human friendly form. With a parameter, this plural @b{targets} command sets the current target to the given name. (i.e.: If there are multiple debug targets) Example: @verbatim (gdb) mon targets CmdName Type Endian ChainPos State -- ---------- ---------- ---------- -------- ---------- 0: target0 arm7tdmi little 0 halted @end verbatim @section target COMMANDS @b{Note:} This command name is SINGULAR - not plural. It is used to manipulate specific targets, to create targets and other things. Once a target is created, a TARGETNAME (object) command is created; see below for details. The TARGET command accepts these sub-commands: @itemize @bullet @item @b{create} .. parameters .. @* creates a new target, see below for details. @item @b{types} @* Lists all supported target types (perhaps some are not yet in this document). @item @b{names} @* Lists all current debug target names, for example: 'str912.cpu' or 'pxa27.cpu' example usage: @verbatim foreach t [target names] { puts [format "Target: %s\n" $t] } @end verbatim @item @b{current} @* Returns the current target. OpenOCD always has, or refers to the ``current target'' in some way. By default, commands like: ``mww'' (used to write memory) operate on the current target. @item @b{number} @b{NUMBER} @* Internally OpenOCD maintains a list of targets - in numerical index (0..N-1) this command returns the name of the target at index N. Example usage: @verbatim set thename [target number $x] puts [format "Target %d is: %s\n" $x $thename] @end verbatim @item @b{count} @* Returns the number of targets known to OpenOCD (see number above) Example: @verbatim set c [target count] for { set x 0 } { $x < $c } { incr x } { # Assuming you have created this function print_target_details $x } @end verbatim @end itemize @section TARGETNAME (object) commands @b{Use:} Once a target is created, an ``object name'' that represents the target is created. By convention, the target name is identical to the tap name. In a multiple target system, one can preceed many common commands with a specific target name and effect only that target. @example str912.cpu mww 0x1234 0x42 omap3530.cpu mww 0x5555 123 @end example @b{Model:} The Tcl/Tk language has the concept of object commands. A good example is a on screen button, once a button is created a button has a name (a path in Tk terms) and that name is useable as a 1st class command. For example in Tk, one can create a button and later configure it like this: @example # Create button .foobar -background red -command @{ foo @} # Modify .foobar configure -foreground blue # Query set x [.foobar cget -background] # Report puts [format "The button is %s" $x] @end example In OpenOCD's terms, the ``target'' is an object just like a Tcl/Tk button. Commands available as a ``target object'' are: @comment START targetobj commands. @itemize @bullet @item @b{configure} - configure the target; see Target Config/Cget Options below @item @b{cget} - query the target configuration; see Target Config/Cget Options below @item @b{curstate} - current target state (running, halt, etc. @item @b{eventlist} @* Intended for a human to see/read the currently configure target events. @item @b{Various Memory Commands} See the ``mww'' command elsewhere. @comment start memory @itemize @bullet @item @b{mww} ... @item @b{mwh} ... @item @b{mwb} ... @item @b{mdw} ... @item @b{mdh} ... @item @b{mdb} ... @comment end memory @end itemize @item @b{Memory To Array, Array To Memory} @* These are aimed at a machine interface to memory @itemize @bullet @item @b{mem2array ARRAYNAME WIDTH ADDRESS COUNT} @item @b{array2mem ARRAYNAME WIDTH ADDRESS COUNT} @* Where: @* @b{ARRAYNAME} is the name of an array variable @* @b{WIDTH} is 8/16/32 - indicating the memory access size @* @b{ADDRESS} is the target memory address @* @b{COUNT} is the number of elements to process @end itemize @item @b{Used during ``reset''} @* These commands are used internally by the OpenOCD scripts to deal with odd reset situations and are not documented here. @itemize @bullet @item @b{arp_examine} @item @b{arp_poll} @item @b{arp_reset} @item @b{arp_halt} @item @b{arp_waitstate} @end itemize @item @b{invoke-event} @b{EVENT-NAME} @* Invokes the specific event manually for the target @end itemize @anchor{Target Events} @section Target Events @cindex events At various times, certain things can happen, or you want them to happen. Examples: @itemize @bullet @item What should happen when GDB connects? Should your target reset? @item When GDB tries to flash the target, do you need to enable the flash via a special command? @item During reset, do you need to write to certain memory location to reconfigure the SDRAM? @end itemize All of the above items are handled by target events. To specify an event action, either during target creation, or later via ``$_TARGETNAME configure'' see this example. Syntactially, the option is: ``-event NAME BODY'' where NAME is a target event name, and BODY is a Tcl procedure or string of commands to execute. The programmers model is the ``-command'' option used in Tcl/Tk buttons and events. Below are two identical examples, the first creates and invokes small procedure. The second inlines the procedure. @example proc my_attach_proc @{ @} @{ puts "RESET...." reset halt @} mychip.cpu configure -event gdb-attach my_attach_proc mychip.cpu configure -event gdb-attach @{ puts "Reset..." reset halt @} @end example @section Current Events The following events are available: @itemize @bullet @item @b{debug-halted} @* The target has halted for debug reasons (i.e.: breakpoint) @item @b{debug-resumed} @* The target has resumed (i.e.: gdb said run) @item @b{early-halted} @* Occurs early in the halt process @item @b{examine-end} @* Currently not used (goal: when JTAG examine completes) @item @b{examine-start} @* Currently not used (goal: when JTAG examine starts) @item @b{gdb-attach} @* When GDB connects @item @b{gdb-detach} @* When GDB disconnects @item @b{gdb-end} @* When the taret has halted and GDB is not doing anything (see early halt) @item @b{gdb-flash-erase-start} @* Before the GDB flash process tries to erase the flash @item @b{gdb-flash-erase-end} @* After the GDB flash process has finished erasing the flash @item @b{gdb-flash-write-start} @* Before GDB writes to the flash @item @b{gdb-flash-write-end} @* After GDB writes to the flash @item @b{gdb-start} @* Before the taret steps, gdb is trying to start/resume the target @item @b{halted} @* The target has halted @item @b{old-gdb_program_config} @* DO NOT USE THIS: Used internally @item @b{old-pre_resume} @* DO NOT USE THIS: Used internally @item @b{reset-assert-pre} @* Before reset is asserted on the tap. @item @b{reset-assert-post} @* Reset is now asserted on the tap. @item @b{reset-deassert-pre} @* Reset is about to be released on the tap @item @b{reset-deassert-post} @* Reset has been released on the tap @item @b{reset-end} @* Currently not used. @item @b{reset-halt-post} @* Currently not usd @item @b{reset-halt-pre} @* Currently not used @item @b{reset-init} @* Used by @b{reset init} command for board-specific initialization. This is where you would configure PLLs and clocking, set up DRAM so you can download programs that don't fit in on-chip SRAM, set up pin multiplexing, and so on. @item @b{reset-start} @* Currently not used @item @b{reset-wait-pos} @* Currently not used @item @b{reset-wait-pre} @* Currently not used @item @b{resume-start} @* Before any target is resumed @item @b{resume-end} @* After all targets have resumed @item @b{resume-ok} @* Success @item @b{resumed} @* Target has resumed @item @b{tap-enable} @* Executed by @b{jtag tapenable DOTTED.NAME} command. Example: @example jtag configure DOTTED.NAME -event tap-enable @{ puts "Enabling CPU" ... @} @end example @item @b{tap-disable} @*Executed by @b{jtag tapdisable DOTTED.NAME} command. Example: @example jtag configure DOTTED.NAME -event tap-disable @{ puts "Disabling CPU" ... @} @end example @end itemize @anchor{Target Create} @section Target Create @cindex target @cindex target creation @example @b{target} @b{create} <@var{NAME}> <@var{TYPE}> <@var{PARAMS ...}> @end example @*This command creates a GDB debug target that refers to a specific JTAG tap. @comment START params @itemize @bullet @item @b{NAME} @* Is the name of the debug target. By convention it should be the tap DOTTED.NAME. This name is also used to create the target object command, and in other places the target needs to be identified. @item @b{TYPE} @* Specifies the target type, i.e.: ARM7TDMI, or Cortex-M3. Currently supported targets are: @comment START types @itemize @minus @item @b{arm7tdmi} @item @b{arm720t} @item @b{arm9tdmi} @item @b{arm920t} @item @b{arm922t} @item @b{arm926ejs} @item @b{arm966e} @item @b{cortex_m3} @item @b{feroceon} @item @b{xscale} @item @b{arm11} @item @b{mips_m4k} @comment end TYPES @end itemize @item @b{PARAMS} @*PARAMs are various target configuration parameters. The following ones are mandatory: @comment START mandatory @itemize @bullet @item @b{-endian big|little} @item @b{-chain-position DOTTED.NAME} @comment end MANDATORY @end itemize @comment END params @end itemize @section Target Config/Cget Options These options can be specified when the target is created, or later via the configure option or to query the target via cget. You should specify a working area if you can; typically it uses some on-chip SRAM. Such a working area can speed up many things, including bulk writes to target memory; flash operations like checking to see if memory needs to be erased; GDB memory checksumming; and may help perform otherwise unavailable operations (like some coprocessor operations on ARM7/9 systems). @itemize @bullet @item @b{-type} - returns the target type @item @b{-event NAME BODY} see Target events @item @b{-work-area-virt [ADDRESS]} specify/set the work area base address which will be used when an MMU is active. @item @b{-work-area-phys [ADDRESS]} specify/set the work area base address which will be used when an MMU is inactive. @item @b{-work-area-size [ADDRESS]} specify/set the work area @item @b{-work-area-backup [0|1]} does the work area get backed up; by default, it doesn't. When possible, use a working_area that doesn't need to be backed up, since performing a backup slows down operations. @item @b{-endian [big|little]} @item @b{-variant [NAME]} some chips have variants OpenOCD needs to know about @item @b{-chain-position DOTTED.NAME} the tap name this target refers to. @end itemize Example: @example for @{ set x 0 @} @{ $x < [target count] @} @{ incr x @} @{ set name [target number $x] set y [$name cget -endian] set z [$name cget -type] puts [format "Chip %d is %s, Endian: %s, type: %s" $x $y $z] @} @end example @section Target Variants @itemize @bullet @item @b{cortex_m3} @* Use variant @option{lm3s} when debugging older Stellaris LM3S targets. This will cause OpenOCD to use a software reset rather than asserting SRST, to avoid a issue with clearing the debug registers. This is fixed in Fury Rev B, DustDevil Rev B, Tempest; these revisions will be detected and the normal reset behaviour used. @item @b{xscale} @*Supported variants are @option{ixp42x}, @option{ixp45x}, @option{ixp46x}, @option{pxa250}, @option{pxa255}, @option{pxa26x}. @item @b{mips_m4k} @* Use variant @option{ejtag_srst} when debugging targets that do not provide a functional SRST line on the EJTAG connector. This causes OpenOCD to instead use an EJTAG software reset command to reset the processor. You still need to enable @option{srst} on the reset configuration command to enable OpenOCD hardware reset functionality. @comment END variants @end itemize @node Flash Commands @chapter Flash Commands OpenOCD has different commands for NOR and NAND flash; the ``flash'' command works with NOR flash, while the ``nand'' command works with NAND flash. This partially reflects different hardware technologies: NOR flash usually supports direct CPU instruction and data bus access, while data from a NAND flash must be copied to memory before it can be used. (SPI flash must also be copied to memory before use.) However, the documentation also uses ``flash'' as a generic term; for example, ``Put flash configuration in board-specific files''. @quotation Note As of 28-nov-2008 OpenOCD does not know how to program a SPI flash that a micro may boot from. Perhaps you, the reader, would like to contribute support for this. @end quotation Flash Steps: @enumerate @item Configure via the command @command{flash bank} @* Do this in a board-specific configuration file, passing parameters as needed by the driver. @item Operate on the flash via @command{flash subcommand} @* Often commands to manipulate the flash are typed by a human, or run via a script in some automated way. Common tasks include writing a boot loader, operating system, or other data. @item GDB Flashing @* Flashing via GDB requires the flash be configured via ``flash bank'', and the GDB flash features be enabled. @xref{GDB Configuration}. @end enumerate Many CPUs have the ablity to ``boot'' from the first flash bank. This means that misprograming that bank can ``brick'' a system, so that it can't boot. JTAG tools, like OpenOCD, are often then used to ``de-brick'' the board by (re)installing working boot firmware. @section Flash Configuration Commands @cindex flash configuration @deffn {Config Command} {flash bank} driver base size chip_width bus_width target [driver_options] Configures a flash bank which provides persistent storage for addresses from @math{base} to @math{base + size - 1}. These banks will often be visible to GDB through the target's memory map. In some cases, configuring a flash bank will activate extra commands; see the driver-specific documentation. @itemize @bullet @item @var{driver} ... identifies the controller driver associated with the flash bank being declared. This is usually @code{cfi} for external flash, or else the name of a microcontroller with embedded flash memory. @xref{Flash Driver List}. @item @var{base} ... Base address of the flash chip. @item @var{size} ... Size of the chip, in bytes. For some drivers, this value is detected from the hardware. @item @var{chip_width} ... Width of the flash chip, in bytes; ignored for most microcontroller drivers. @item @var{bus_width} ... Width of the data bus used to access the chip, in bytes; ignored for most microcontroller drivers. @item @var{target} ... Names the target used to issue commands to the flash controller. @comment Actually, it's currently a controller-specific parameter... @item @var{driver_options} ... drivers may support, or require, additional parameters. See the driver-specific documentation for more information. @end itemize @quotation Note This command is not available after OpenOCD initialization has completed. Use it in board specific configuration files, not interactively. @end quotation @end deffn @comment the REAL name for this command is "ocd_flash_banks" @comment less confusing would be: "flash list" (like "nand list") @deffn Command {flash banks} Prints a one-line summary of each device declared using @command{flash bank}, numbered from zero. Note that this is the @emph{plural} form; the @emph{singular} form is a very different command. @end deffn @deffn Command {flash probe} num Identify the flash, or validate the parameters of the configured flash. Operation depends on the flash type. The @var{num} parameter is a value shown by @command{flash banks}. Most flash commands will implicitly @emph{autoprobe} the bank; flash drivers can distinguish between probing and autoprobing, but most don't bother. @end deffn @section Erasing, Reading, Writing to Flash @cindex flash erasing @cindex flash reading @cindex flash writing @cindex flash programming One feature distinguishing NOR flash from NAND or serial flash technologies is that for read access, it acts exactly like any other addressible memory. This means you can use normal memory read commands like @command{mdw} or @command{dump_image} with it, with no special @command{flash} subcommands. @xref{Memory access}, and @ref{Image access}. Write access works differently. Flash memory normally needs to be erased before it's written. Erasing a sector turns all of its bits to ones, and writing can turn ones into zeroes. This is why there are special commands for interactive erasing and writing, and why GDB needs to know which parts of the address space hold NOR flash memory. @quotation Note Most of these erase and write commands leverage the fact that NOR flash chips consume target address space. They implicitly refer to the current JTAG target, and map from an address in that target's address space back to a flash bank. @comment In May 2009, those mappings may fail if any bank associated @comment with that target doesn't succesfuly autoprobe ... bug worth fixing? A few commands use abstract addressing based on bank and sector numbers, and don't depend on searching the current target and its address space. Avoid confusing the two command models. @end quotation Some flash chips implement software protection against accidental writes, since such buggy writes could in some cases ``brick'' a system. For such systems, erasing and writing may require sector protection to be disabled first. Examples include CFI flash such as ``Intel Advanced Bootblock flash'', and AT91SAM7 on-chip flash. @xref{flash protect}. @anchor{flash erase_sector} @deffn Command {flash erase_sector} num first last Erase sectors in bank @var{num}, starting at sector @var{first} up to and including @var{last}. Sector numbering starts at 0. The @var{num} parameter is a value shown by @command{flash banks}. @end deffn @deffn Command {flash erase_address} address length Erase sectors starting at @var{address} for @var{length} bytes. The flash bank to use is inferred from the @var{address}, and the specified length must stay within that bank. As a special case, when @var{length} is zero and @var{address} is the start of the bank, the whole flash is erased. @end deffn @deffn Command {flash fillw} address word length @deffnx Command {flash fillh} address halfword length @deffnx Command {flash fillb} address byte length Fills flash memory with the specified @var{word} (32 bits), @var{halfword} (16 bits), or @var{byte} (8-bit) pattern, starting at @var{address} and continuing for @var{length} units (word/halfword/byte). No erasure is done before writing; when needed, that must be done before issuing this command. Writes are done in blocks of up to 1024 bytes, and each write is verified by reading back the data and comparing it to what was written. The flash bank to use is inferred from the @var{address} of each block, and the specified length must stay within that bank. @end deffn @comment no current checks for errors if fill blocks touch multiple banks! @anchor{flash write_bank} @deffn Command {flash write_bank} num filename offset Write the binary @file{filename} to flash bank @var{num}, starting at @var{offset} bytes from the beginning of the bank. The @var{num} parameter is a value shown by @command{flash banks}. @end deffn @anchor{flash write_image} @deffn Command {flash write_image} [erase] filename [offset] [type] Write the image @file{filename} to the current target's flash bank(s). A relocation @var{offset} may be specified, in which case it is added to the base address for each section in the image. The file [@var{type}] can be specified explicitly as @option{bin} (binary), @option{ihex} (Intel hex), @option{elf} (ELF file), @option{s19} (Motorola s19). @option{mem}, or @option{builder}. The relevant flash sectors will be erased prior to programming if the @option{erase} parameter is given. The flash bank to use is inferred from the @var{address} of each image segment. @end deffn @section Other Flash commands @cindex flash protection @deffn Command {flash erase_check} num Check erase state of sectors in flash bank @var{num}, and display that status. The @var{num} parameter is a value shown by @command{flash banks}. This is the only operation that updates the erase state information displayed by @option{flash info}. That means you have to issue an @command{flash erase_check} command after erasing or programming the device to get updated information. (Code execution may have invalidated any state records kept by OpenOCD.) @end deffn @deffn Command {flash info} num Print info about flash bank @var{num} The @var{num} parameter is a value shown by @command{flash banks}. The information includes per-sector protect status. @end deffn @anchor{flash protect} @deffn Command {flash protect} num first last (on|off) Enable (@var{on}) or disable (@var{off}) protection of flash sectors @var{first} to @var{last} of flash bank @var{num}. The @var{num} parameter is a value shown by @command{flash banks}. @end deffn @deffn Command {flash protect_check} num Check protection state of sectors in flash bank @var{num}. The @var{num} parameter is a value shown by @command{flash banks}. @comment @option{flash erase_sector} using the same syntax. @end deffn @anchor{Flash Driver List} @section Flash Drivers, Options, and Commands As noted above, the @command{flash bank} command requires a driver name, and allows driver-specific options and behaviors. Some drivers also activate driver-specific commands. @subsection External Flash @deffn {Flash Driver} cfi @cindex Common Flash Interface @cindex CFI The ``Common Flash Interface'' (CFI) is the main standard for external NOR flash chips, each of which connects to a specific external chip select on the CPU. Frequently the first such chip is used to boot the system. Your board's @code{reset-init} handler might need to configure additional chip selects using other commands (like: @command{mww} to configure a bus and its timings) , or perhaps configure a GPIO pin that controls the ``write protect'' pin on the flash chip. The CFI driver can use a target-specific working area to significantly speed up operation. The CFI driver can accept the following optional parameters, in any order: @itemize @item @var{jedec_probe} ... is used to detect certain non-CFI flash ROMs, like AM29LV010 and similar types. @item @var{x16_as_x8} ... @end itemize To configure two adjacent banks of 16 MBytes each, both sixteen bits (two bytes) wide on a sixteen bit bus: @example flash bank cfi 0x00000000 0x01000000 2 2 $_TARGETNAME flash bank cfi 0x01000000 0x01000000 2 2 $_TARGETNAME @end example @end deffn @subsection Internal Flash (Microcontrollers) @deffn {Flash Driver} aduc702x The ADUC702x analog microcontrollers from ST Micro include internal flash and use ARM7TDMI cores. The aduc702x flash driver works with models ADUC7019 through ADUC7028. The setup command only requires the @var{target} argument since all devices in this family have the same memory layout. @example flash bank aduc702x 0 0 0 0 $_TARGETNAME @end example @end deffn @deffn {Flash Driver} at91sam7 All members of the AT91SAM7 microcontroller family from Atmel include internal flash and use ARM7TDMI cores. The driver automatically recognizes a number of these chips using the chip identification register, and autoconfigures itself. @example flash bank at91sam7 0 0 0 0 $_TARGETNAME @end example For chips which are not recognized by the controller driver, you must provide additional parameters in the following order: @itemize @item @var{chip_model} ... label used with @command{flash info} @item @var{banks} @item @var{sectors_per_bank} @item @var{pages_per_sector} @item @var{pages_size} @item @var{num_nvm_bits} @item @var{freq_khz} ... required if an external clock is provided, optional (but recommended) when the oscillator frequency is known @end itemize It is recommended that you provide zeroes for all of those values except the clock frequency, so that everything except that frequency will be autoconfigured. Knowing the frequency helps ensure correct timings for flash access. The flash controller handles erases automatically on a page (128/256 byte) basis, so explicit erase commands are not necessary for flash programming. However, there is an ``EraseAll`` command that can erase an entire flash plane (of up to 256KB), and it will be used automatically when you issue @command{flash erase_sector} or @command{flash erase_address} commands. @deffn Command {at91sam7 gpnvm} bitnum (set|clear) Set or clear a ``General Purpose Non-Volatle Memory'' (GPNVM) bit for the processor. Each processor has a number of such bits, used for controlling features such as brownout detection (so they are not truly general purpose). @quotation Note This assumes that the first flash bank (number 0) is associated with the appropriate at91sam7 target. @end quotation @end deffn @end deffn @deffn {Flash Driver} avr The AVR 8-bit microcontrollers from Atmel integrate flash memory. @emph{The current implementation is incomplete.} @comment - defines mass_erase ... pointless given flash_erase_address @end deffn @deffn {Flash Driver} ecosflash @emph{No idea what this is...} The @var{ecosflash} driver defines one mandatory parameter, the name of a modules of target code which is downloaded and executed. @end deffn @deffn {Flash Driver} lpc2000 Most members of the LPC2000 microcontroller family from NXP include internal flash and use ARM7TDMI cores. The @var{lpc2000} driver defines two mandatory and one optional parameters, which must appear in the following order: @itemize @item @var{variant} ... required, may be @var{lpc2000_v1} (older LPC21xx and LPC22xx) or @var{lpc2000_v2} (LPC213x, LPC214x, LPC210[123], LPC23xx and LPC24xx) @item @var{clock_kHz} ... the frequency, in kiloHertz, at which the core is running @item @var{calc_checksum} ... optional (but you probably want to provide this!), telling the driver to calculate a valid checksum for the exception vector table. @end itemize LPC flashes don't require the chip and bus width to be specified. @example flash bank lpc2000 0x0 0x7d000 0 0 $_TARGETNAME \ lpc2000_v2 14765 calc_checksum @end example @end deffn @deffn {Flash Driver} lpc288x The LPC2888 microcontroller from NXP needs slightly different flash support from its lpc2000 siblings. The @var{lpc288x} driver defines one mandatory parameter, the programming clock rate in Hz. LPC flashes don't require the chip and bus width to be specified. @example flash bank lpc288x 0 0 0 0 $_TARGETNAME 12000000 @end example @end deffn @deffn {Flash Driver} ocl @emph{No idea what this is, other than using some arm7/arm9 core.} @example flash bank ocl 0 0 0 0 $_TARGETNAME @end example @end deffn @deffn {Flash Driver} pic32mx The PIC32MX microcontrollers are based on the MIPS 4K cores, and integrate flash memory. @emph{The current implementation is incomplete.} @example flash bank pix32mx 0 0 0 0 $_TARGETNAME @end example @comment numerous *disabled* commands are defined: @comment - chip_erase ... pointless given flash_erase_address @comment - lock, unlock ... pointless given protect on/off (yes?) @comment - pgm_word ... shouldn't bank be deduced from address?? Some pic32mx-specific commands are defined: @deffn Command {pic32mx pgm_word} address value bank Programs the specified 32-bit @var{value} at the given @var{address} in the specified chip @var{bank}. @end deffn @end deffn @deffn {Flash Driver} stellaris All members of the Stellaris LM3Sxxx microcontroller family from Texas Instruments include internal flash and use ARM Cortex M3 cores. The driver automatically recognizes a number of these chips using the chip identification register, and autoconfigures itself. @footnote{Currently there is a @command{stellaris mass_erase} command. That seems pointless since the same effect can be had using the standard @command{flash erase_address} command.} @example flash bank stellaris 0 0 0 0 $_TARGETNAME @end example @end deffn @deffn {Flash Driver} stm32x All members of the STM32 microcontroller family from ST Microelectronics include internal flash and use ARM Cortex M3 cores. The driver automatically recognizes a number of these chips using the chip identification register, and autoconfigures itself. @example flash bank stm32x 0 0 0 0 $_TARGETNAME @end example Some stm32x-specific commands @footnote{Currently there is a @command{stm32x mass_erase} command. That seems pointless since the same effect can be had using the standard @command{flash erase_address} command.} are defined: @deffn Command {stm32x lock} num Locks the entire stm32 device. The @var{num} parameter is a value shown by @command{flash banks}. @end deffn @deffn Command {stm32x unlock} num Unlocks the entire stm32 device. The @var{num} parameter is a value shown by @command{flash banks}. @end deffn @deffn Command {stm32x options_read} num Read and display the stm32 option bytes written by the @command{stm32x options_write} command. The @var{num} parameter is a value shown by @command{flash banks}. @end deffn @deffn Command {stm32x options_write} num (SWWDG|HWWDG) (RSTSTNDBY|NORSTSTNDBY) (RSTSTOP|NORSTSTOP) Writes the stm32 option byte with the specified values. The @var{num} parameter is a value shown by @command{flash banks}. @end deffn @end deffn @deffn {Flash Driver} str7x All members of the STR7 microcontroller family from ST Microelectronics include internal flash and use ARM7TDMI cores. The @var{str7x} driver defines one mandatory parameter, @var{variant}, which is either @code{STR71x}, @code{STR73x} or @code{STR75x}. @example flash bank str7x 0x40000000 0x00040000 0 0 $_TARGETNAME STR71x @end example @end deffn @deffn {Flash Driver} str9x Most members of the STR9 microcontroller family from ST Microelectronics include internal flash and use ARM966E cores. The str9 needs the flash controller to be configured using the @command{str9x flash_config} command prior to Flash programming. @example flash bank str9x 0x40000000 0x00040000 0 0 $_TARGETNAME str9x flash_config 0 4 2 0 0x80000 @end example @deffn Command {str9x flash_config} num bbsr nbbsr bbadr nbbadr Configures the str9 flash controller. The @var{num} parameter is a value shown by @command{flash banks}. @itemize @bullet @item @var{bbsr} - Boot Bank Size register @item @var{nbbsr} - Non Boot Bank Size register @item @var{bbadr} - Boot Bank Start Address register @item @var{nbbadr} - Boot Bank Start Address register @end itemize @end deffn @end deffn @deffn {Flash Driver} tms470 Most members of the TMS470 microcontroller family from Texas Instruments include internal flash and use ARM7TDMI cores. This driver doesn't require the chip and bus width to be specified. Some tms470-specific commands are defined: @deffn Command {tms470 flash_keyset} key0 key1 key2 key3 Saves programming keys in a register, to enable flash erase and write commands. @end deffn @deffn Command {tms470 osc_mhz} clock_mhz Reports the clock speed, which is used to calculate timings. @end deffn @deffn Command {tms470 plldis} (0|1) Disables (@var{1}) or enables (@var{0}) use of the PLL to speed up the flash clock. @end deffn @end deffn @subsection str9xpec driver @cindex str9xpec Here is some background info to help you better understand how this driver works. OpenOCD has two flash drivers for the str9: @enumerate @item Standard driver @option{str9x} programmed via the str9 core. Normally used for flash programming as it is faster than the @option{str9xpec} driver. @item Direct programming @option{str9xpec} using the flash controller. This is an ISC compilant (IEEE 1532) tap connected in series with the str9 core. The str9 core does not need to be running to program using this flash driver. Typical use for this driver is locking/unlocking the target and programming the option bytes. @end enumerate Before we run any commands using the @option{str9xpec} driver we must first disable the str9 core. This example assumes the @option{str9xpec} driver has been configured for flash bank 0. @example # assert srst, we do not want core running # while accessing str9xpec flash driver jtag_reset 0 1 # turn off target polling poll off # disable str9 core str9xpec enable_turbo 0 # read option bytes str9xpec options_read 0 # re-enable str9 core str9xpec disable_turbo 0 poll on reset halt @end example The above example will read the str9 option bytes. When performing a unlock remember that you will not be able to halt the str9 - it has been locked. Halting the core is not required for the @option{str9xpec} driver as mentioned above, just issue the commands above manually or from a telnet prompt. @subsubsection str9xpec driver options @b{flash bank str9xpec} <@var{base}> <@var{size}> 0 0 <@var{target}> @*Before using the flash commands the turbo mode must be enabled using str9xpec @option{enable_turbo} <@var{num>.} Only use this driver for locking/unlocking the device or configuring the option bytes. Use the standard str9 driver for programming. @subsubsection str9xpec specific commands @cindex str9xpec specific commands These are flash specific commands when using the str9xpec driver. @itemize @bullet @item @b{str9xpec enable_turbo} <@var{num}> @cindex str9xpec enable_turbo @*enable turbo mode, will simply remove the str9 from the chain and talk directly to the embedded flash controller. @item @b{str9xpec disable_turbo} <@var{num}> @cindex str9xpec disable_turbo @*restore the str9 into JTAG chain. @item @b{str9xpec lock} <@var{num}> @cindex str9xpec lock @*lock str9 device. The str9 will only respond to an unlock command that will erase the device. @item @b{str9xpec unlock} <@var{num}> @cindex str9xpec unlock @*unlock str9 device. @item @b{str9xpec options_read} <@var{num}> @cindex str9xpec options_read @*read str9 option bytes. @item @b{str9xpec options_write} <@var{num}> @cindex str9xpec options_write @*write str9 option bytes. @end itemize @subsubsection STR9 option byte configuration @cindex STR9 option byte configuration @itemize @bullet @item @b{str9xpec options_cmap} <@var{num}> <@option{bank0}|@option{bank1}> @cindex str9xpec options_cmap @*configure str9 boot bank. @item @b{str9xpec options_lvdthd} <@var{num}> <@option{2.4v}|@option{2.7v}> @cindex str9xpec options_lvdthd @*configure str9 lvd threshold. @item @b{str9xpec options_lvdsel} <@var{num}> <@option{vdd}|@option{vdd_vddq}> @cindex str9xpec options_lvdsel @*configure str9 lvd source. @item @b{str9xpec options_lvdwarn} <@var{bank}> <@option{vdd}|@option{vdd_vddq}> @cindex str9xpec options_lvdwarn @*configure str9 lvd reset warning source. @end itemize @section mFlash @subsection mFlash Configuration @cindex mFlash Configuration @b{mflash bank} <@var{soc}> <@var{base}> <@var{RST pin}> <@var{target}> @cindex mflash bank @*Configures a mflash for <@var{soc}> host bank at <@var{base}>. Pin number format is dependent on host GPIO calling convention. Currently, mflash bank support s3c2440 and pxa270. (ex. of s3c2440) mflash <@var{RST pin}> is GPIO B1. @example mflash bank s3c2440 0x10000000 1b 0 @end example (ex. of pxa270) mflash <@var{RST pin}> is GPIO 43. @example mflash bank pxa270 0x08000000 43 0 @end example @subsection mFlash commands @cindex mFlash commands @itemize @bullet @item @b{mflash probe} @cindex mflash probe @*Probe mflash. @item @b{mflash write} <@var{num}> <@var{file}> <@var{offset}> @cindex mflash write @*Write the binary <@var{file}> to mflash bank <@var{num}>, starting at <@var{offset}> bytes from the beginning of the bank. @item @b{mflash dump} <@var{num}> <@var{file}> <@var{offset}> <@var{size}> @cindex mflash dump @*Dump bytes, starting at <@var{offset}> bytes from the beginning of the <@var{num}> bank to a <@var{file}>. @item @b{mflash config pll} <@var{frequency}> @cindex mflash config pll @*Configure mflash pll. <@var{frequency}> is input frequency of mflash. The order is Hz. Issuing this command will erase mflash's whole internal nand and write new pll. After this command, mflash needs power-on-reset for normal operation. If pll was newly configured, storage and boot(optional) info also need to be update. @item @b{mflash config boot} @cindex mflash config boot @*Configure bootable option. If bootable option is set, mflash offer the first 8 sectors (4kB) for boot. @item @b{mflash config storage} @cindex mflash config storage @*Configure storage information. For the normal storage operation, this information must be written. @end itemize @node NAND Flash Commands @chapter NAND Flash Commands @cindex NAND Compared to NOR or SPI flash, NAND devices are inexpensive and high density. Today's NAND chips, and multi-chip modules, commonly hold multiple GigaBytes of data. NAND chips consist of a number of ``erase blocks'' of a given size (such as 128 KBytes), each of which is divided into a number of pages (of perhaps 512 or 2048 bytes each). Each page of a NAND flash has an ``out of band'' (OOB) area to hold Error Correcting Code (ECC) and other metadata, usually 16 bytes of OOB for every 512 bytes of page data. One key characteristic of NAND flash is that its error rate is higher than that of NOR flash. In normal operation, that ECC is used to correct and detect errors. However, NAND blocks can also wear out and become unusable; those blocks are then marked "bad". NAND chips are even shipped from the manufacturer with a few bad blocks. The highest density chips use a technology (MLC) that wears out more quickly, so ECC support is increasingly important as a way to detect blocks that have begun to fail, and help to preserve data integrity with techniques such as wear leveling. Software is used to manage the ECC. Some controllers don't support ECC directly; in those cases, software ECC is used. Other controllers speed up the ECC calculations with hardware. Single-bit error correction hardware is routine. Controllers geared for newer MLC chips may correct 4 or more errors for every 512 bytes of data. You will need to make sure that any data you write using OpenOCD includes the apppropriate kind of ECC. For example, that may mean passing the @code{oob_softecc} flag when writing NAND data, or ensuring that the correct hardware ECC mode is used. The basic steps for using NAND devices include: @enumerate @item Declare via the command @command{nand device} @* Do this in a board-specific configuration file, passing parameters as needed by the controller. @item Configure each device using @command{nand probe}. @* Do this only after the associated target is set up, such as in its reset-init script or in procures defined to access that device. @item Operate on the flash via @command{nand subcommand} @* Often commands to manipulate the flash are typed by a human, or run via a script in some automated way. Common task include writing a boot loader, operating system, or other data needed to initialize or de-brick a board. @end enumerate @b{NOTE:} At the time this text was written, the largest NAND flash fully supported by OpenOCD is 2 GiBytes (16 GiBits). This is because the variables used to hold offsets and lengths are only 32 bits wide. (Larger chips may work in some cases, unless an offset or length is larger than 0xffffffff, the largest 32-bit unsigned integer.) Some larger devices will work, since they are actually multi-chip modules with two smaller chips and individual chipselect lines. @section NAND Configuration Commands @cindex NAND configuration NAND chips must be declared in configuration scripts, plus some additional configuration that's done after OpenOCD has initialized. @deffn {Config Command} {nand device} controller target [configparams...] Declares a NAND device, which can be read and written to after it has been configured through @command{nand probe}. In OpenOCD, devices are single chips; this is unlike some operating systems, which may manage multiple chips as if they were a single (larger) device. In some cases, configuring a device will activate extra commands; see the controller-specific documentation. @b{NOTE:} This command is not available after OpenOCD initialization has completed. Use it in board specific configuration files, not interactively. @itemize @bullet @item @var{controller} ... identifies the controller driver associated with the NAND device being declared. @xref{NAND Driver List}. @item @var{target} ... names the target used when issuing commands to the NAND controller. @comment Actually, it's currently a controller-specific parameter... @item @var{configparams} ... controllers may support, or require, additional parameters. See the controller-specific documentation for more information. @end itemize @end deffn @deffn Command {nand list} Prints a one-line summary of each device declared using @command{nand device}, numbered from zero. Note that un-probed devices show no details. @end deffn @deffn Command {nand probe} num Probes the specified device to determine key characteristics like its page and block sizes, and how many blocks it has. The @var{num} parameter is the value shown by @command{nand list}. You must (successfully) probe a device before you can use it with most other NAND commands. @end deffn @section Erasing, Reading, Writing to NAND Flash @deffn Command {nand dump} num filename offset length [oob_option] @cindex NAND reading Reads binary data from the NAND device and writes it to the file, starting at the specified offset. The @var{num} parameter is the value shown by @command{nand list}. Use a complete path name for @var{filename}, so you don't depend on the directory used to start the OpenOCD server. The @var{offset} and @var{length} must be exact multiples of the device's page size. They describe a data region; the OOB data associated with each such page may also be accessed. @b{NOTE:} At the time this text was written, no error correction was done on the data that's read, unless raw access was disabled and the underlying NAND controller driver had a @code{read_page} method which handled that error correction. By default, only page data is saved to the specified file. Use an @var{oob_option} parameter to save OOB data: @itemize @bullet @item no oob_* parameter @*Output file holds only page data; OOB is discarded. @item @code{oob_raw} @*Output file interleaves page data and OOB data; the file will be longer than "length" by the size of the spare areas associated with each data page. Note that this kind of "raw" access is different from what's implied by @command{nand raw_access}, which just controls whether a hardware-aware access method is used. @item @code{oob_only} @*Output file has only raw OOB data, and will be smaller than "length" since it will contain only the spare areas associated with each data page. @end itemize @end deffn @deffn Command {nand erase} num offset length @cindex NAND erasing @cindex NAND programming Erases blocks on the specified NAND device, starting at the specified @var{offset} and continuing for @var{length} bytes. Both of those values must be exact multiples of the device's block size, and the region they specify must fit entirely in the chip. The @var{num} parameter is the value shown by @command{nand list}. @b{NOTE:} This command will try to erase bad blocks, when told to do so, which will probably invalidate the manufacturer's bad block marker. For the remainder of the current server session, @command{nand info} will still report that the block ``is'' bad. @end deffn @deffn Command {nand write} num filename offset [option...] @cindex NAND writing @cindex NAND programming Writes binary data from the file into the specified NAND device, starting at the specified offset. Those pages should already have been erased; you can't change zero bits to one bits. The @var{num} parameter is the value shown by @command{nand list}. Use a complete path name for @var{filename}, so you don't depend on the directory used to start the OpenOCD server. The @var{offset} must be an exact multiple of the device's page size. All data in the file will be written, assuming it doesn't run past the end of the device. Only full pages are written, and any extra space in the last page will be filled with 0xff bytes. (That includes OOB data, if that's being written.) @b{NOTE:} At the time this text was written, bad blocks are ignored. That is, this routine will not skip bad blocks, but will instead try to write them. This can cause problems. Provide at most one @var{option} parameter. With some NAND drivers, the meanings of these parameters may change if @command{nand raw_access} was used to disable hardware ECC. @itemize @bullet @item no oob_* parameter @*File has only page data, which is written. If raw acccess is in use, the OOB area will not be written. Otherwise, if the underlying NAND controller driver has a @code{write_page} routine, that routine may write the OOB with hardware-computed ECC data. @item @code{oob_only} @*File has only raw OOB data, which is written to the OOB area. Each page's data area stays untouched. @i{This can be a dangerous option}, since it can invalidate the ECC data. You may need to force raw access to use this mode. @item @code{oob_raw} @*File interleaves data and OOB data, both of which are written If raw access is enabled, the data is written first, then the un-altered OOB. Otherwise, if the underlying NAND controller driver has a @code{write_page} routine, that routine may modify the OOB before it's written, to include hardware-computed ECC data. @item @code{oob_softecc} @*File has only page data, which is written. The OOB area is filled with 0xff, except for a standard 1-bit software ECC code stored in conventional locations. You might need to force raw access to use this mode, to prevent the underlying driver from applying hardware ECC. @item @code{oob_softecc_kw} @*File has only page data, which is written. The OOB area is filled with 0xff, except for a 4-bit software ECC specific to the boot ROM in Marvell Kirkwood SoCs. You might need to force raw access to use this mode, to prevent the underlying driver from applying hardware ECC. @end itemize @end deffn @section Other NAND commands @cindex NAND other commands @deffn Command {nand check_bad_blocks} [offset length] Checks for manufacturer bad block markers on the specified NAND device. If no parameters are provided, checks the whole device; otherwise, starts at the specified @var{offset} and continues for @var{length} bytes. Both of those values must be exact multiples of the device's block size, and the region they specify must fit entirely in the chip. The @var{num} parameter is the value shown by @command{nand list}. @b{NOTE:} Before using this command you should force raw access with @command{nand raw_access enable} to ensure that the underlying driver will not try to apply hardware ECC. @end deffn @deffn Command {nand info} num The @var{num} parameter is the value shown by @command{nand list}. This prints the one-line summary from "nand list", plus for devices which have been probed this also prints any known status for each block. @end deffn @deffn Command {nand raw_access} num Sets or clears an flag affecting how page I/O is done. The @var{num} parameter is the value shown by @command{nand list}. This flag is cleared (disabled) by default, but changing that value won't affect all NAND devices. The key factor is whether the underlying driver provides @code{read_page} or @code{write_page} methods. If it doesn't provide those methods, the setting of this flag is irrelevant; all access is effectively ``raw''. When those methods exist, they are normally used when reading data (@command{nand dump} or reading bad block markers) or writing it (@command{nand write}). However, enabling raw access (setting the flag) prevents use of those methods, bypassing hardware ECC logic. @i{This can be a dangerous option}, since writing blocks with the wrong ECC data can cause them to be marked as bad. @end deffn @anchor{NAND Driver List} @section NAND Drivers, Options, and Commands As noted above, the @command{nand device} command allows driver-specific options and behaviors. Some controllers also activate controller-specific commands. @deffn {NAND Driver} davinci This driver handles the NAND controllers found on DaVinci family chips from Texas Instruments. It takes three extra parameters: address of the NAND chip; hardware ECC mode to use (hwecc1, hwecc4, hwecc4_infix); address of the AEMIF controller on this processor. @example nand device davinci dm355.arm 0x02000000 hwecc4 0x01e10000 @end example All DaVinci processors support the single-bit ECC hardware, and newer ones also support the four-bit ECC hardware. The @code{write_page} and @code{read_page} methods are used to implement those ECC modes, unless they are disabled using the @command{nand raw_access} command. @end deffn @deffn {NAND Driver} lpc3180 These controllers require an extra @command{nand device} parameter: the clock rate used by the controller. @deffn Command {lpc3180 select} num [mlc|slc] Configures use of the MLC or SLC controller mode. MLC implies use of hardware ECC. The @var{num} parameter is the value shown by @command{nand list}. @end deffn At this writing, this driver includes @code{write_page} and @code{read_page} methods. Using @command{nand raw_access} to disable those methods will prevent use of hardware ECC in the MLC controller mode, but won't change SLC behavior. @end deffn @comment current lpc3180 code won't issue 5-byte address cycles @deffn {NAND Driver} orion These controllers require an extra @command{nand device} parameter: the address of the controller. @example nand device orion 0xd8000000 @end example These controllers don't define any specialized commands. At this writing, their drivers don't include @code{write_page} or @code{read_page} methods, so @command{nand raw_access} won't change any behavior. @end deffn @deffn {NAND Driver} s3c2410 @deffnx {NAND Driver} s3c2412 @deffnx {NAND Driver} s3c2440 @deffnx {NAND Driver} s3c2443 These S3C24xx family controllers don't have any special @command{nand device} options, and don't define any specialized commands. At this writing, their drivers don't include @code{write_page} or @code{read_page} methods, so @command{nand raw_access} won't change any behavior. @end deffn @node General Commands @chapter General Commands @cindex commands The commands documented in this chapter here are common commands that you, as a human, may want to type and see the output of. Configuration type commands are documented elsewhere. Intent: @itemize @bullet @item @b{Source Of Commands} @* OpenOCD commands can occur in a configuration script (discussed elsewhere) or typed manually by a human or supplied programatically, or via one of several TCP/IP Ports. @item @b{From the human} @* A human should interact with the telnet interface (default port: 4444) or via GDB (default port 3333). To issue commands from within a GDB session, use the @option{monitor} command, e.g. use @option{monitor poll} to issue the @option{poll} command. All output is relayed through the GDB session. @item @b{Machine Interface} The Tcl interface's intent is to be a machine interface. The default Tcl port is 5555. @end itemize @section Daemon Commands @subsection sleep [@var{msec}] @cindex sleep @*Wait for n milliseconds before resuming. Useful in connection with script files (@var{script} command and @var{target_script} configuration). @subsection shutdown @cindex shutdown @*Close the OpenOCD daemon, disconnecting all clients (GDB, telnet, other). @anchor{debug_level} @subsection debug_level [@var{n}] @cindex debug_level @*Display or adjust debug level to n<0-3> @subsection fast [@var{enable|disable}] @cindex fast @*Default disabled. Set default behaviour of OpenOCD to be "fast and dangerous". For instance ARM7/9 DCC memory downloads and fast memory access will work if the JTAG interface isn't too fast and the core doesn't run at a too low frequency. Note that this option only changes the default and that the indvidual options, like DCC memory downloads, can be enabled and disabled individually. The target specific "dangerous" optimisation tweaking options may come and go as more robust and user friendly ways are found to ensure maximum throughput and robustness with a minimum of configuration. Typically the "fast enable" is specified first on the command line: @example openocd -c "fast enable" -c "interface dummy" -f target/str710.cfg @end example @subsection echo <@var{message}> @cindex echo @*Output message to stdio. e.g. echo "Programming - please wait" @subsection log_output <@var{file}> @cindex log_output @*Redirect logging to (default: stderr) @subsection script <@var{file}> @cindex script @*Execute commands from See also: ``source [find FILENAME]'' @section Target state handling @subsection power <@var{on}|@var{off}> @cindex reg @*Turn power switch to target on/off. No arguments: print status. Not all interfaces support this. @subsection reg [@option{#}|@option{name}] [value] @cindex reg @*Access a single register by its number[@option{#}] or by its [@option{name}]. No arguments: list all available registers for the current target. Number or name argument: display a register. Number or name and value arguments: set register value. @subsection poll [@option{on}|@option{off}] @cindex poll @*Poll the target for its current state. If the target is in debug mode, architecture specific information about the current state is printed. An optional parameter allows continuous polling to be enabled and disabled. @subsection halt [@option{ms}] @cindex halt @*Send a halt request to the target and wait for it to halt for up to [@option{ms}] milliseconds. Default [@option{ms}] is 5 seconds if no arg given. Optional arg @option{ms} is a timeout in milliseconds. Using 0 as the [@option{ms}] will stop OpenOCD from waiting. @subsection wait_halt [@option{ms}] @cindex wait_halt @*Wait for the target to enter debug mode. Optional [@option{ms}] is a timeout in milliseconds. Default [@option{ms}] is 5 seconds if no arg is given. @subsection resume [@var{address}] @cindex resume @*Resume the target at its current code position, or at an optional address. OpenOCD will wait 5 seconds for the target to resume. @subsection step [@var{address}] @cindex step @*Single-step the target at its current code position, or at an optional address. @anchor{Reset Command} @subsection reset [@option{run}|@option{halt}|@option{init}] @cindex reset @*Perform a hard-reset. The optional parameter specifies what should happen after the reset. If there is no parameter, a @command{reset run} is executed. The other options will not work on all systems. @xref{Reset Configuration}. @itemize @minus @item @b{run} @cindex reset run @*Let the target run. @item @b{halt} @cindex reset halt @*Immediately halt the target (works only with certain configurations). @item @b{init} @cindex reset init @*Immediately halt the target, and execute the reset script (works only with certain configurations) @end itemize @subsection soft_reset_halt @cindex reset @*Requesting target halt and executing a soft reset. This is often used when a target cannot be reset and halted. The target, after reset is released begins to execute code. OpenOCD attempts to stop the CPU and then sets the program counter back to the reset vector. Unfortunately the code that was executed may have left the hardware in an unknown state. @anchor{Memory access} @section Memory access commands @subsection meminfo display available RAM memory on OpenOCD host. Used in OpenOCD regression testing scripts. Mainly useful on embedded targets, PC type hosts have complimentary tools like Valgrind to address resource tracking problems. @subsection Memory peek/poke type commands These commands allow accesses of a specific size to the memory system. Often these are used to configure the current target in some special way. For example - one may need to write certian values to the SDRAM controller to enable SDRAM. @enumerate @item To change the current target see the ``targets'' (plural) command @item In system level scripts these commands are deprecated, please use the TARGET object versions. @end enumerate @itemize @bullet @item @b{mdw} <@var{addr}> [@var{count}] @cindex mdw @*display memory words (32bit) @item @b{mdh} <@var{addr}> [@var{count}] @cindex mdh @*display memory half-words (16bit) @item @b{mdb} <@var{addr}> [@var{count}] @cindex mdb @*display memory bytes (8bit) @item @b{mww} <@var{addr}> <@var{value}> @cindex mww @*write memory word (32bit) @item @b{mwh} <@var{addr}> <@var{value}> @cindex mwh @*write memory half-word (16bit) @item @b{mwb} <@var{addr}> <@var{value}> @cindex mwb @*write memory byte (8bit) @end itemize @anchor{Image access} @section Image loading commands @anchor{load_image} @subsection load_image @b{load_image} <@var{file}> <@var{address}> [@option{bin}|@option{ihex}|@option{elf}] @cindex load_image @*Load image <@var{file}> to target memory at <@var{address}> @subsection fast_load_image @b{fast_load_image} <@var{file}> <@var{address}> [@option{bin}|@option{ihex}|@option{elf}] @cindex fast_load_image @*Normally you should be using @b{load_image} or GDB load. However, for testing purposes or when I/O overhead is significant(OpenOCD running on an embedded host), storing the image in memory and uploading the image to the target can be a way to upload e.g. multiple debug sessions when the binary does not change. Arguments are the same as @b{load_image}, but the image is stored in OpenOCD host memory, i.e. does not affect target. This approach is also useful when profiling target programming performance as I/O and target programming can easily be profiled separately. @subsection fast_load @b{fast_load} @cindex fast_image @*Loads an image stored in memory by @b{fast_load_image} to the current target. Must be preceeded by fast_load_image. @anchor{dump_image} @subsection dump_image @b{dump_image} <@var{file}> <@var{address}> <@var{size}> @cindex dump_image @*Dump <@var{size}> bytes of target memory starting at <@var{address}> to a (binary) <@var{file}>. @subsection verify_image @b{verify_image} <@var{file}> <@var{address}> [@option{bin}|@option{ihex}|@option{elf}] @cindex verify_image @*Verify <@var{file}> against target memory starting at <@var{address}>. This will first attempt a comparison using a CRC checksum, if this fails it will try a binary compare. @section Breakpoint commands @cindex Breakpoint commands @itemize @bullet @item @b{bp} <@var{addr}> <@var{len}> [@var{hw}] @cindex bp @*set breakpoint
[hw] @item @b{rbp} <@var{addr}> @cindex rbp @*remove breakpoint @item @b{wp} <@var{addr}> <@var{len}> <@var{r}|@var{w}|@var{a}> [@var{value}] [@var{mask}] @cindex wp @*set watchpoint
[value] [mask] @item @b{rwp} <@var{addr}> @cindex rwp @*remove watchpoint @end itemize @section Misc Commands @cindex Other Target Commands @itemize @item @b{profile} <@var{seconds}> <@var{gmon.out}> Profiling samples the CPU's program counter as quickly as possible, which is useful for non-intrusive stochastic profiling. @end itemize @node Architecture and Core Commands @chapter Architecture and Core Commands @cindex Architecture Specific Commands @cindex Core Specific Commands Most CPUs have specialized JTAG operations to support debugging. OpenOCD packages most such operations in its standard command framework. Some of those operations don't fit well in that framework, so they are exposed here as architecture or implementation (core) specific commands. @anchor{ARM Tracing} @section ARM Tracing @cindex ETM @cindex ETB CPUs based on ARM cores may include standard tracing interfaces, based on an ``Embedded Trace Module'' (ETM) which sends voluminous address and data bus trace records to a ``Trace Port''. @itemize @item Development-oriented boards will sometimes provide a high speed trace connector for collecting that data, when the particular CPU supports such an interface. (The standard connector is a 38-pin Mictor, with both JTAG and trace port support.) Those trace connectors are supported by higher end JTAG adapters and some logic analyzer modules; frequently those modules can buffer several megabytes of trace data. Configuring an ETM coupled to such an external trace port belongs in the board-specific configuration file. @item If the CPU doesn't provide an external interface, it probably has an ``Embedded Trace Buffer'' (ETB) on the chip, which is a dedicated SRAM. 4KBytes is one common ETB size. Configuring an ETM coupled only to an ETB belongs in the CPU-specific (target) configuration file, since it works the same on all boards. @end itemize ETM support in OpenOCD doesn't seem to be widely used yet. @quotation Issues ETM support may be buggy, and at least some @command{etm config} parameters should be detected by asking the ETM for them. It seems like a GDB hookup should be possible, as well as triggering trace on specific events (perhaps @emph{handling IRQ 23} or @emph{calls foo()}). There should be GUI tools to manipulate saved trace data and help analyse it in conjunction with the source code. It's unclear how much of a common interface is shared with the current XScale trace support, or should be shared with eventual Nexus-style trace module support. @end quotation @subsection ETM Configuration ETM setup is coupled with the trace port driver configuration. @deffn {Config Command} {etm config} target width mode clocking driver Declares the ETM associated with @var{target}, and associates it with a given trace port @var{driver}. @xref{Trace Port Drivers}. Several of the parameters must reflect the trace port configuration. The @var{width} must be either 4, 8, or 16. The @var{mode} must be @option{normal}, @option{multiplexted}, or @option{demultiplexted}. The @var{clocking} must be @option{half} or @option{full}. @quotation Note You can see the ETM registers using the @command{reg} command, although not all of those possible registers are present in every ETM. @end quotation @end deffn @deffn Command {etm info} Displays information about the current target's ETM. @end deffn @deffn Command {etm status} Displays status of the current target's ETM: is the ETM idle, or is it collecting data? Did trace data overflow? Was it triggered? @end deffn @deffn Command {etm tracemode} [type context_id_bits cycle_accurate branch_output] Displays what data that ETM will collect. If arguments are provided, first configures that data. When the configuration changes, tracing is stopped and any buffered trace data is invalidated. @itemize @item @var{type} ... one of @option{none} (save nothing), @option{data} (save data), @option{address} (save addresses), @option{all} (save data and addresses) @item @var{context_id_bits} ... 0, 8, 16, or 32 @item @var{cycle_accurate} ... @option{enable} or @option{disable} @item @var{branch_output} ... @option{enable} or @option{disable} @end itemize @end deffn @deffn Command {etm trigger_percent} percent @emph{Buggy and effectively a NOP ... @var{percent} from 2..100} @end deffn @subsection ETM Trace Operation After setting up the ETM, you can use it to collect data. That data can be exported to files for later analysis. It can also be parsed with OpenOCD, for basic sanity checking. @deffn Command {etm analyze} Reads trace data into memory, if it wasn't already present. Decodes and prints the data that was collected. @end deffn @deffn Command {etm dump} filename Stores the captured trace data in @file{filename}. @end deffn @deffn Command {etm image} filename [base_address] [type] Opens an image file. @end deffn @deffn Command {etm load} filename Loads captured trace data from @file{filename}. @end deffn @deffn Command {etm start} Starts trace data collection. @end deffn @deffn Command {etm stop} Stops trace data collection. @end deffn @anchor{Trace Port Drivers} @subsection Trace Port Drivers To use an ETM trace port it must be associated with a driver. @deffn {Trace Port Driver} dummy Use the @option{dummy} driver if you are configuring an ETM that's not connected to anything (on-chip ETB or off-chip trace connector). @emph{This driver lets OpenOCD talk to the ETM, but it does not expose any trace data collection.} @deffn {Config Command} {etm_dummy config} target Associates the ETM for @var{target} with a dummy driver. @end deffn @end deffn @deffn {Trace Port Driver} etb Use the @option{etb} driver if you are configuring an ETM to use on-chip ETB memory. @deffn {Config Command} {etb config} target etb_tap Associates the ETM for @var{target} with the ETB at @var{etb_tap}. You can see the ETB registers using the @command{reg} command. @end deffn @end deffn @deffn {Trace Port Driver} oocd_trace This driver isn't available unless OpenOCD was explicitly configured with the @option{--enable-oocd_trace} option. You probably don't want to configure it unless you've built the appropriate prototype hardware; it's @emph{proof-of-concept} software. Use the @option{oocd_trace} driver if you are configuring an ETM that's connected to an off-chip trace connector. @deffn {Config Command} {oocd_trace config} target tty Associates the ETM for @var{target} with a trace driver which collects data through the serial port @var{tty}. @end deffn @deffn Command {oocd_trace resync} Re-synchronizes with the capture clock. @end deffn @deffn Command {oocd_trace status} Reports whether the capture clock is locked or not. @end deffn @end deffn @section ARMv4 and ARMv5 Architecture @cindex ARMv4 specific commands @cindex ARMv5 specific commands These commands are specific to ARM architecture v4 and v5, including all ARM7 or ARM9 systems and Intel XScale. They are available in addition to other core-specific commands that may be available. @deffn Command {armv4_5 core_state} [arm|thumb] Displays the core_state, optionally changing it to process either @option{arm} or @option{thumb} instructions. The target may later be resumed in the currently set core_state. (Processors may also support the Jazelle state, but that is not currently supported in OpenOCD.) @end deffn @deffn Command {armv4_5 disassemble} address count [thumb] @cindex disassemble Disassembles @var{count} instructions starting at @var{address}. If @option{thumb} is specified, Thumb (16-bit) instructions are used; else ARM (32-bit) instructions are used. (Processors may also support the Jazelle state, but those instructions are not currently understood by OpenOCD.) @end deffn @deffn Command {armv4_5 reg} Display a list of all banked core registers, fetching the current value from every core mode if necessary. OpenOCD versions before rev. 60 didn't fetch the current register value. @end deffn @subsection ARM7 and ARM9 specific commands @cindex ARM7 specific commands @cindex ARM9 specific commands These commands are specific to ARM7 and ARM9 cores, like ARM7TDMI, ARM720T, ARM9TDMI, ARM920T or ARM926EJ-S. They are available in addition to the ARMv4/5 commands, and any other core-specific commands that may be available. @deffn Command {arm7_9 dbgrq} (enable|disable) Control use of the EmbeddedIce DBGRQ signal to force entry into debug mode, instead of breakpoints. This should be safe for all but ARM7TDMI--S cores (like Philips LPC). @end deffn @deffn Command {arm7_9 dcc_downloads} (enable|disable) @cindex DCC Control the use of the debug communications channel (DCC) to write larger (>128 byte) amounts of memory. DCC downloads offer a huge speed increase, but might be unsafe, especially with targets running at very low speeds. This command was introduced with OpenOCD rev. 60, and requires a few bytes of working area. @end deffn @anchor{arm7_9 fast_memory_access} @deffn Command {arm7_9 fast_memory_access} (enable|disable) Enable or disable memory writes and reads that don't check completion of the operation. This provides a huge speed increase, especially with USB JTAG cables (FT2232), but might be unsafe if used with targets running at very low speeds, like the 32kHz startup clock of an AT91RM9200. @end deffn @deffn {Debug Command} {arm7_9 write_core_reg} num mode word @emph{This is intended for use while debugging OpenOCD; you probably shouldn't use it.} Writes a 32-bit @var{word} to register @var{num} (from 0 to 16) as used in the specified @var{mode} (where e.g. mode 16 is "user" and mode 19 is "supervisor"; the M4..M0 bits of the PSR). Registers 0..15 are the normal CPU registers such as r0(0), r1(1) ... pc(15). Register 16 is the mode-specific SPSR, unless the specified mode is 0xffffffff (32-bit all-ones) in which case register 16 is the CPSR. The write goes directly to the CPU, bypassing the register cache. @end deffn @deffn {Debug Command} {arm7_9 write_xpsr} word (0|1) @emph{This is intended for use while debugging OpenOCD; you probably shouldn't use it.} If the second parameter is zero, writes @var{word} to the Current Program Status register (CPSR). Else writes @var{word} to the current mode's Saved PSR (SPSR). In both cases, this bypasses the register cache. @end deffn @deffn {Debug Command} {arm7_9 write_xpsr_im8} byte rotate (0|1) @emph{This is intended for use while debugging OpenOCD; you probably shouldn't use it.} Writes eight bits to the CPSR or SPSR, first rotating them by @math{2*rotate} bits, and bypassing the register cache. This has lower JTAG overhead than writing the entire CPSR or SPSR with @command{arm7_9 write_xpsr}. @end deffn @subsection ARM720T specific commands @cindex ARM720T specific commands These commands are available to ARM720T based CPUs, which are implementations of the ARMv4T architecture based on the ARM7TDMI-S integer core. They are available in addition to the ARMv4/5 and ARM7/ARM9 commands. @deffn Command {arm720t cp15} regnum [value] Display cp15 register @var{regnum}; else if a @var{value} is provided, that value is written to that register. @end deffn @deffn Command {arm720t mdw_phys} addr [count] @deffnx Command {arm720t mdh_phys} addr [count] @deffnx Command {arm720t mdb_phys} addr [count] Display contents of physical address @var{addr}, as 32-bit words (@command{mdw_phys}), 16-bit halfwords (@command{mdh_phys}), or 8-bit bytes (@command{mdb_phys}). If @var{count} is specified, displays that many units. @end deffn @deffn Command {arm720t mww_phys} addr word @deffnx Command {arm720t mwh_phys} addr halfword @deffnx Command {arm720t mwb_phys} addr byte Writes the specified @var{word} (32 bits), @var{halfword} (16 bits), or @var{byte} (8-bit) pattern, at the specified physical address @var{addr}. @end deffn @deffn Command {arm720t virt2phys} va Translate a virtual address @var{va} to a physical address and display the result. @end deffn @subsection ARM9TDMI specific commands @cindex ARM9TDMI specific commands Many ARM9-family CPUs are built around ARM9TDMI integer cores, or processors resembling ARM9TDMI, and can use these commands. Such cores include the ARM920T, ARM926EJ-S, and ARM966. @deffn Command {arm9tdmi vector_catch} (all|none|list) Catch arm9 interrupt vectors, can be @option{all}, @option{none}, or a list with one or more of the following: @option{reset} @option{undef} @option{swi} @option{pabt} @option{dabt} @option{reserved} @option{irq} @option{fiq}. @end deffn @subsection ARM920T specific commands @cindex ARM920T specific commands These commands are available to ARM920T based CPUs, which are implementations of the ARMv4T architecture built using the ARM9TDMI integer core. They are available in addition to the ARMv4/5, ARM7/ARM9, and ARM9TDMI commands. @deffn Command {arm920t cache_info} Print information about the caches found. This allows to see whether your target is an ARM920T (2x16kByte cache) or ARM922T (2x8kByte cache). @end deffn @deffn Command {arm920t cp15} regnum [value] Display cp15 register @var{regnum}; else if a @var{value} is provided, that value is written to that register. @end deffn @deffn Command {arm920t cp15i} opcode [value [address]] Interpreted access using cp15 @var{opcode}. If no @var{value} is provided, the result is displayed. Else if that value is written using the specified @var{address}, or using zero if no other address is not provided. @end deffn @deffn Command {arm920t mdw_phys} addr [count] @deffnx Command {arm920t mdh_phys} addr [count] @deffnx Command {arm920t mdb_phys} addr [count] Display contents of physical address @var{addr}, as 32-bit words (@command{mdw_phys}), 16-bit halfwords (@command{mdh_phys}), or 8-bit bytes (@command{mdb_phys}). If @var{count} is specified, displays that many units. @end deffn @deffn Command {arm920t mww_phys} addr word @deffnx Command {arm920t mwh_phys} addr halfword @deffnx Command {arm920t mwb_phys} addr byte Writes the specified @var{word} (32 bits), @var{halfword} (16 bits), or @var{byte} (8-bit) pattern, at the specified physical address @var{addr}. @end deffn @deffn Command {arm920t read_cache} filename Dump the content of ICache and DCache to a file named @file{filename}. @end deffn @deffn Command {arm920t read_mmu} filename Dump the content of the ITLB and DTLB to a file named @file{filename}. @end deffn @deffn Command {arm920t virt2phys} @var{va} Translate a virtual address @var{va} to a physical address and display the result. @end deffn @subsection ARM926EJ-S specific commands @cindex ARM926EJ-S specific commands These commands are available to ARM926EJ-S based CPUs, which are implementations of the ARMv5TEJ architecture based on the ARM9EJ-S integer core. They are available in addition to the ARMv4/5, ARM7/ARM9, and ARM9TDMI commands. @deffn Command {arm926ejs cache_info} Print information about the caches found. @end deffn @deffn Command {arm926ejs cp15} opcode1 opcode2 CRn CRm regnum [value] Accesses cp15 register @var{regnum} using @var{opcode1}, @var{opcode2}, @var{CRn}, and @var{CRm}. If a @var{value} is provided, that value is written to that register. Else that register is read and displayed. @end deffn @deffn Command {arm926ejs mdw_phys} addr [count] @deffnx Command {arm926ejs mdh_phys} addr [count] @deffnx Command {arm926ejs mdb_phys} addr [count] Display contents of physical address @var{addr}, as 32-bit words (@command{mdw_phys}), 16-bit halfwords (@command{mdh_phys}), or 8-bit bytes (@command{mdb_phys}). If @var{count} is specified, displays that many units. @end deffn @deffn Command {arm926ejs mww_phys} addr word @deffnx Command {arm926ejs mwh_phys} addr halfword @deffnx Command {arm926ejs mwb_phys} addr byte Writes the specified @var{word} (32 bits), @var{halfword} (16 bits), or @var{byte} (8-bit) pattern, at the specified physical address @var{addr}. @end deffn @deffn Command {arm926ejs virt2phys} @var{va} Translate a virtual address @var{va} to a physical address and display the result. @end deffn @subsection ARM966E specific commands @cindex ARM966E specific commands These commands are available to ARM966 based CPUs, which are implementations of the ARMv5TE architecture. They are available in addition to the ARMv4/5, ARM7/ARM9, and ARM9TDMI commands. @deffn Command {arm966e cp15} regnum [value] Display cp15 register @var{regnum}; else if a @var{value} is provided, that value is written to that register. @end deffn @subsection XScale specific commands @cindex XScale specific commands These commands are available to XScale based CPUs, which are implementations of the ARMv5TE architecture. @deffn Command {xscale analyze_trace} Displays the contents of the trace buffer. @end deffn @deffn Command {xscale cache_clean_address} address Changes the address used when cleaning the data cache. @end deffn @deffn Command {xscale cache_info} Displays information about the CPU caches. @end deffn @deffn Command {xscale cp15} regnum [value] Display cp15 register @var{regnum}; else if a @var{value} is provided, that value is written to that register. @end deffn @deffn Command {xscale debug_handler} target address Changes the address used for the specified target's debug handler. @end deffn @deffn Command {xscale dcache} (enable|disable) Enables or disable the CPU's data cache. @end deffn @deffn Command {xscale dump_trace} filename Dumps the raw contents of the trace buffer to @file{filename}. @end deffn @deffn Command {xscale icache} (enable|disable) Enables or disable the CPU's instruction cache. @end deffn @deffn Command {xscale mmu} (enable|disable) Enables or disable the CPU's memory management unit. @end deffn @deffn Command {xscale trace_buffer} (enable|disable) [fill [n] | wrap] Enables or disables the trace buffer, and controls how it is emptied. @end deffn @deffn Command {xscale trace_image} filename [offset [type]] Opens a trace image from @file{filename}, optionally rebasing its segment addresses by @var{offset}. The image @var{type} may be one of @option{bin} (binary), @option{ihex} (Intel hex), @option{elf} (ELF file), @option{s19} (Motorola s19), @option{mem}, or @option{builder}. @end deffn @deffn Command {xscale vector_catch} mask Provide a bitmask showing the vectors to catch. @end deffn @section ARMv6 Architecture @subsection ARM11 specific commands @cindex ARM11 specific commands @deffn Command {arm11 mcr} p1 p2 p3 p4 p5 Read coprocessor register @end deffn @deffn Command {arm11 memwrite burst} [value] Displays the value of the memwrite burst-enable flag, which is enabled by default. If @var{value} is defined, first assigns that. @end deffn @deffn Command {arm11 memwrite error_fatal} [value] Displays the value of the memwrite error_fatal flag, which is enabled by default. If @var{value} is defined, first assigns that. @end deffn @deffn Command {arm11 mrc} p1 p2 p3 p4 p5 value Write coprocessor register @end deffn @deffn Command {arm11 no_increment} [value] Displays the value of the flag controlling whether some read or write operations increment the pointer (the default behavior) or not (acting like a FIFO). If @var{value} is defined, first assigns that. @end deffn @deffn Command {arm11 step_irq_enable} [value] Displays the value of the flag controlling whether IRQs are enabled during single stepping; they is disabled by default. If @var{value} is defined, first assigns that. @end deffn @section ARMv7 Architecture @subsection Cortex-M3 specific commands @cindex Cortex-M3 specific commands @deffn Command {cortex_m3 maskisr} (on|off) Control masking (disabling) interrupts during target step/resume. @end deffn @section Target DCC Requests @cindex Linux-ARM DCC support @cindex libdcc @cindex DCC OpenOCD can handle certain target requests; currently debugmsgs @command{target_request debugmsgs} are only supported for arm7_9 and cortex_m3. See libdcc in the contrib dir for more details. Linux-ARM kernels have a ``Kernel low-level debugging via EmbeddedICE DCC channel'' option (CONFIG_DEBUG_ICEDCC, depends on CONFIG_DEBUG_LL) which uses this mechanism to deliver messages before a serial console can be activated. @deffn Command {target_request debugmsgs} [enable|disable|charmsg] Displays current handling of target DCC message requests. These messages may be sent to the debugger while the target is running. The optional @option{enable} and @option{charmsg} parameters both enable the messages, while @option{disable} disables them. With @option{charmsg} the DCC words each contain one character, as used by Linux with CONFIG_DEBUG_ICEDCC; otherwise the libdcc format is used. @end deffn @node JTAG Commands @chapter JTAG Commands @cindex JTAG Commands Generally most people will not use the bulk of these commands. They are mostly used by the OpenOCD developers or those who need to directly manipulate the JTAG taps. In general these commands control JTAG taps at a very low level. For example if you need to control a JTAG Route Controller (i.e.: the OMAP3530 on the Beagle Board has one) you might use these commands in a script or an event procedure. @section Commands @cindex Commands @itemize @bullet @item @b{scan_chain} @cindex scan_chain @*Print current scan chain configuration. @item @b{jtag_reset} <@var{trst}> <@var{srst}> @cindex jtag_reset @*Toggle reset lines. @item @b{endstate} <@var{tap_state}> @cindex endstate @*Finish JTAG operations in <@var{tap_state}>. @item @b{runtest} <@var{num_cycles}> @cindex runtest @*Move to Run-Test/Idle, and execute <@var{num_cycles}> @item @b{statemove} [@var{tap_state}] @cindex statemove @*Move to current endstate or [@var{tap_state}] @item @b{irscan} <@var{device}> <@var{instr}> [@var{dev2}] [@var{instr2}] ... @cindex irscan @*Execute IR scan <@var{device}> <@var{instr}> [@var{dev2}] [@var{instr2}] ... @item @b{drscan} <@var{device}> [@var{dev2}] [@var{var2}] ... @cindex drscan @*Execute DR scan <@var{device}> [@var{dev2}] [@var{var2}] ... @item @b{verify_ircapture} <@option{enable}|@option{disable}> @cindex verify_ircapture @*Verify value captured during Capture-IR. Default is enabled. @item @b{var} <@var{name}> [@var{num_fields}|@var{del}] [@var{size1}] ... @cindex var @*Allocate, display or delete variable <@var{name}> [@var{num_fields}|@var{del}] [@var{size1}] ... @item @b{field} <@var{var}> <@var{field}> [@var{value}|@var{flip}] @cindex field Display/modify variable field <@var{var}> <@var{field}> [@var{value}|@var{flip}]. @end itemize @section Tap states @cindex Tap states Available tap_states are: @itemize @bullet @item @b{RESET} @cindex RESET @item @b{IDLE} @cindex IDLE @item @b{DRSELECT} @cindex DRSELECT @item @b{DRCAPTURE} @cindex DRCAPTURE @item @b{DRSHIFT} @cindex DRSHIFT @item @b{DREXIT1} @cindex DREXIT1 @item @b{DRPAUSE} @cindex DRPAUSE @item @b{DREXIT2} @cindex DREXIT2 @item @b{DRUPDATE} @cindex DRUPDATE @item @b{IRSELECT} @cindex IRSELECT @item @b{IRCAPTURE} @cindex IRCAPTURE @item @b{IRSHIFT} @cindex IRSHIFT @item @b{IREXIT1} @cindex IREXIT1 @item @b{IRPAUSE} @cindex IRPAUSE @item @b{IREXIT2} @cindex IREXIT2 @item @b{IRUPDATE} @cindex IRUPDATE @end itemize @node TFTP @chapter TFTP @cindex TFTP If OpenOCD runs on an embedded host(as ZY1000 does), then TFTP can be used to access files on PCs (either the developer's PC or some other PC). The way this works on the ZY1000 is to prefix a filename by "/tftp/ip/" and append the TFTP path on the TFTP server (tftpd). For example, @example load_image /tftp/10.0.0.96/c:\temp\abc.elf @end example will load c:\temp\abc.elf from the developer pc (10.0.0.96) into memory as if the file was hosted on the embedded host. In order to achieve decent performance, you must choose a TFTP server that supports a packet size bigger than the default packet size (512 bytes). There are numerous TFTP servers out there (free and commercial) and you will have to do a bit of googling to find something that fits your requirements. @node Sample Scripts @chapter Sample Scripts @cindex scripts This page shows how to use the Target Library. The configuration script can be divided into the following sections: @itemize @bullet @item Daemon configuration @item Interface @item JTAG scan chain @item Target configuration @item Flash configuration @end itemize Detailed information about each section can be found at OpenOCD configuration. @section AT91R40008 example @cindex AT91R40008 example To start OpenOCD with a target script for the AT91R40008 CPU and reset the CPU upon startup of the OpenOCD daemon. @example openocd -f interface/parport.cfg -f target/at91r40008.cfg \ -c "init" -c "reset" @end example @node GDB and OpenOCD @chapter GDB and OpenOCD @cindex GDB OpenOCD complies with the remote gdbserver protocol, and as such can be used to debug remote targets. @anchor{Connecting to GDB} @section Connecting to GDB @cindex Connecting to GDB Use GDB 6.7 or newer with OpenOCD if you run into trouble. For instance GDB 6.3 has a known bug that produces bogus memory access errors, which has since been fixed: look up 1836 in @url{http://sourceware.org/cgi-bin/gnatsweb.pl?database=gdb} OpenOCD can communicate with GDB in two ways: @enumerate @item A socket (TCP/IP) connection is typically started as follows: @example target remote localhost:3333 @end example This would cause GDB to connect to the gdbserver on the local pc using port 3333. @item A pipe connection is typically started as follows: @example target remote | openocd --pipe @end example This would cause GDB to run OpenOCD and communicate using pipes (stdin/stdout). Using this method has the advantage of GDB starting/stopping OpenOCD for the debug session. @end enumerate To list the available OpenOCD commands type @command{monitor help} on the GDB command line. OpenOCD supports the gdb @option{qSupported} packet, this enables information to be sent by the GDB remote server (i.e. OpenOCD) to GDB. Typical information includes packet size and the device's memory map. Previous versions of OpenOCD required the following GDB options to increase the packet size and speed up GDB communication: @example set remote memory-write-packet-size 1024 set remote memory-write-packet-size fixed set remote memory-read-packet-size 1024 set remote memory-read-packet-size fixed @end example This is now handled in the @option{qSupported} PacketSize and should not be required. @section Programming using GDB @cindex Programming using GDB By default the target memory map is sent to GDB. This can be disabled by the following OpenOCD configuration option: @example gdb_memory_map disable @end example For this to function correctly a valid flash configuration must also be set in OpenOCD. For faster performance you should also configure a valid working area. Informing GDB of the memory map of the target will enable GDB to protect any flash areas of the target and use hardware breakpoints by default. This means that the OpenOCD option @command{gdb_breakpoint_override} is not required when using a memory map. @xref{gdb_breakpoint_override}. To view the configured memory map in GDB, use the GDB command @option{info mem} All other unassigned addresses within GDB are treated as RAM. GDB 6.8 and higher set any memory area not in the memory map as inaccessible. This can be changed to the old behaviour by using the following GDB command @example set mem inaccessible-by-default off @end example If @command{gdb_flash_program enable} is also used, GDB will be able to program any flash memory using the vFlash interface. GDB will look at the target memory map when a load command is given, if any areas to be programmed lie within the target flash area the vFlash packets will be used. If the target needs configuring before GDB programming, an event script can be executed: @example $_TARGETNAME configure -event EVENTNAME BODY @end example To verify any flash programming the GDB command @option{compare-sections} can be used. @node Tcl Scripting API @chapter Tcl Scripting API @cindex Tcl Scripting API @cindex Tcl scripts @section API rules The commands are stateless. E.g. the telnet command line has a concept of currently active target, the Tcl API proc's take this sort of state information as an argument to each proc. There are three main types of return values: single value, name value pair list and lists. Name value pair. The proc 'foo' below returns a name/value pair list. @verbatim > set foo(me) Duane > set foo(you) Oyvind > set foo(mouse) Micky > set foo(duck) Donald If one does this: > set foo The result is: me Duane you Oyvind mouse Micky duck Donald Thus, to get the names of the associative array is easy: foreach { name value } [set foo] { puts "Name: $name, Value: $value" } @end verbatim Lists returned must be relatively small. Otherwise a range should be passed in to the proc in question. @section Internal low-level Commands By low-level, the intent is a human would not directly use these commands. Low-level commands are (should be) prefixed with "ocd_", e.g. @command{ocd_flash_banks} is the low level API upon which @command{flash banks} is implemented. @itemize @bullet @item @b{ocd_mem2array} <@var{varname}> <@var{width}> <@var{addr}> <@var{nelems}> Read memory and return as a Tcl array for script processing @item @b{ocd_array2mem} <@var{varname}> <@var{width}> <@var{addr}> <@var{nelems}> Convert a Tcl array to memory locations and write the values @item @b{ocd_flash_banks} <@var{driver}> <@var{base}> <@var{size}> <@var{chip_width}> <@var{bus_width}> <@var{target}> [@option{driver options} ...] Return information about the flash banks @end itemize OpenOCD commands can consist of two words, e.g. "flash banks". The startup.tcl "unknown" proc will translate this into a Tcl proc called "flash_banks". @section OpenOCD specific Global Variables @subsection HostOS Real Tcl has ::tcl_platform(), and platform::identify, and many other variables. JimTCL, as implemented in OpenOCD creates $HostOS which holds one of the following values: @itemize @bullet @item @b{winxx} Built using Microsoft Visual Studio @item @b{linux} Linux is the underlying operating sytem @item @b{darwin} Darwin (mac-os) is the underlying operating sytem. @item @b{cygwin} Running under Cygwin @item @b{mingw32} Running under MingW32 @item @b{other} Unknown, none of the above. @end itemize Note: 'winxx' was choosen because today (March-2009) no distinction is made between Win32 and Win64. @quotation Note We should add support for a variable like Tcl variable @code{tcl_platform(platform)}, it should be called @code{jim_platform} (because it is jim, not real tcl). @end quotation @node Upgrading @chapter Deprecated/Removed Commands @cindex Deprecated/Removed Commands Certain OpenOCD commands have been deprecated or removed during the various revisions. Upgrade your scripts as soon as possible. These descriptions for old commands may be removed a year after the command itself was removed. This means that in January 2010 this chapter may become much shorter. @itemize @bullet @item @b{arm7_9 fast_writes} @cindex arm7_9 fast_writes @*Use @command{arm7_9 fast_memory_access} instead. @xref{arm7_9 fast_memory_access}. @item @b{arm7_9 force_hw_bkpts} @*Use @command{gdb_breakpoint_override} instead. Note that GDB will use hardware breakpoints for flash if the GDB memory map has been set up(default when flash is declared in target configuration). @xref{gdb_breakpoint_override}. @item @b{arm7_9 sw_bkpts} @*On by default. @xref{gdb_breakpoint_override}. @item @b{daemon_startup} @*this config option has been removed, simply adding @option{init} and @option{reset halt} to the end of your config script will give the same behaviour as using @option{daemon_startup reset} and @option{target cortex_m3 little reset_halt 0}. @item @b{dump_binary} @*use @option{dump_image} command with same args. @xref{dump_image}. @item @b{flash erase} @*use @option{flash erase_sector} command with same args. @xref{flash erase_sector}. @item @b{flash write} @*use @option{flash write_bank} command with same args. @xref{flash write_bank}. @item @b{flash write_binary} @*use @option{flash write_bank} command with same args. @xref{flash write_bank}. @item @b{flash auto_erase} @*use @option{flash write_image} command passing @option{erase} as the first parameter. @xref{flash write_image}. @item @b{jtag_device} @*use the @command{jtag newtap} command, converting from positional syntax to named prefixes, and naming the TAP. @xref{jtag newtap}. Note that if you try to use the old command, a message will tell you the right new command to use; and that the fourth parameter in the old syntax was never actually used. @example OLD: jtag_device 8 0x01 0xe3 0xfe NEW: jtag newtap CHIPNAME TAPNAME \ -irlen 8 -ircapture 0x01 -irmask 0xe3 @end example @item @b{jtag_speed} value @*@xref{JTAG Speed}. Usually, a value of zero means maximum speed. The actual effect of this option depends on the JTAG interface used. @itemize @minus @item wiggler: maximum speed / @var{number} @item ft2232: 6MHz / (@var{number}+1) @item amt jtagaccel: 8 / 2**@var{number} @item jlink: maximum speed in kHz (0-12000), 0 will use RTCK @item rlink: 24MHz / @var{number}, but only for certain values of @var{number} @comment end speed list. @end itemize @item @b{load_binary} @*use @option{load_image} command with same args. @xref{load_image}. @item @b{run_and_halt_time} @*This command has been removed for simpler reset behaviour, it can be simulated with the following commands: @smallexample reset run sleep 100 halt @end smallexample @item @b{target} <@var{type}> <@var{endian}> <@var{jtag-position}> @*use the create subcommand of @option{target}. @item @b{target_script} <@var{target#}> <@var{eventname}> <@var{scriptname}> @*use <@var{target_name}> configure -event <@var{eventname}> "script <@var{scriptname}>" @item @b{working_area} @*use the @option{configure} subcommand of @option{target} to set the work-area-virt, work-area-phy, work-area-size, and work-area-backup properties of the target. @end itemize @node FAQ @chapter FAQ @cindex faq @enumerate @anchor{FAQ RTCK} @item @b{RTCK, also known as: Adaptive Clocking - What is it?} @cindex RTCK @cindex adaptive clocking @* In digital circuit design it is often refered to as ``clock synchronisation'' the JTAG interface uses one clock (TCK or TCLK) operating at some speed, your target is operating at another. The two clocks are not synchronised, they are ``asynchronous'' In order for the two to work together they must be synchronised. Otherwise the two systems will get out of sync with each other and nothing will work. There are 2 basic options: @enumerate @item Use a special circuit. @item One clock must be some multiple slower than the other. @end enumerate @b{Does this really matter?} For some chips and some situations, this is a non-issue (i.e.: A 500MHz ARM926) but for others - for example some Atmel SAM7 and SAM9 chips start operation from reset at 32kHz - program/enable the oscillators and eventually the main clock. It is in those critical times you must slow the JTAG clock to sometimes 1 to 4kHz. Imagine debugging a 500MHz ARM926 hand held battery powered device that ``deep sleeps'' at 32kHz between every keystroke. It can be painful. @b{Solution #1 - A special circuit} In order to make use of this, your JTAG dongle must support the RTCK feature. Not all dongles support this - keep reading! The RTCK signal often found in some ARM chips is used to help with this problem. ARM has a good description of the problem described at this link: @url{http://www.arm.com/support/faqdev/4170.html} [checked 28/nov/2008]. Link title: ``How does the JTAG synchronisation logic work? / how does adaptive clocking work?''. The nice thing about adaptive clocking is that ``battery powered hand held device example'' - the adaptiveness works perfectly all the time. One can set a break point or halt the system in the deep power down code, slow step out until the system speeds up. @b{Solution #2 - Always works - but may be slower} Often this is a perfectly acceptable solution. In most simple terms: Often the JTAG clock must be 1/10 to 1/12 of the target clock speed. But what that ``magic division'' is varies depending on the chips on your board. @b{ARM rule of thumb} Most ARM based systems require an 8:1 division. @b{Xilinx rule of thumb} is 1/12 the clock speed. Note: Many FTDI2232C based JTAG dongles are limited to 6MHz. You can still debug the 'low power' situations - you just need to manually adjust the clock speed at every step. While painful and tedious, it is not always practical. It is however easy to ``code your way around it'' - i.e.: Cheat a little, have a special debug mode in your application that does a ``high power sleep''. If you are careful - 98% of your problems can be debugged this way. To set the JTAG frequency use the command: @example # Example: 1.234MHz jtag_khz 1234 @end example @item @b{Win32 Pathnames} Why don't backslashes work in Windows paths? OpenOCD uses Tcl and a backslash is an escape char. Use @{ and @} around Windows filenames. @example > echo \a > echo @{\a@} \a > echo "\a" > @end example @item @b{Missing: cygwin1.dll} OpenOCD complains about a missing cygwin1.dll. Make sure you have Cygwin installed, or at least a version of OpenOCD that claims to come with all the necessary DLLs. When using Cygwin, try launching OpenOCD from the Cygwin shell. @item @b{Breakpoint Issue} I'm trying to set a breakpoint using GDB (or a frontend like Insight or Eclipse), but OpenOCD complains that "Info: arm7_9_common.c:213 arm7_9_add_breakpoint(): sw breakpoint requested, but software breakpoints not enabled". GDB issues software breakpoints when a normal breakpoint is requested, or to implement source-line single-stepping. On ARMv4T systems, like ARM7TDMI, ARM720T or ARM920T, software breakpoints consume one of the two available hardware breakpoints. @item @b{LPC2000 Flash} When erasing or writing LPC2000 on-chip flash, the operation fails at random. Make sure the core frequency specified in the @option{flash lpc2000} line matches the clock at the time you're programming the flash. If you've specified the crystal's frequency, make sure the PLL is disabled. If you've specified the full core speed (e.g. 60MHz), make sure the PLL is enabled. @item @b{Amontec Chameleon} When debugging using an Amontec Chameleon in its JTAG Accelerator configuration, I keep getting "Error: amt_jtagaccel.c:184 amt_wait_scan_busy(): amt_jtagaccel timed out while waiting for end of scan, rtck was disabled". Make sure your PC's parallel port operates in EPP mode. You might have to try several settings in your PC BIOS (ECP, EPP, and different versions of those). @item @b{Data Aborts} When debugging with OpenOCD and GDB (plain GDB, Insight, or Eclipse), I get lots of "Error: arm7_9_common.c:1771 arm7_9_read_memory(): memory read caused data abort". The errors are non-fatal, and are the result of GDB trying to trace stack frames beyond the last valid frame. It might be possible to prevent this by setting up a proper "initial" stack frame, if you happen to know what exactly has to be done, feel free to add this here. @b{Simple:} In your startup code - push 8 registers of zeros onto the stack before calling main(). What GDB is doing is ``climbing'' the run time stack by reading various values on the stack using the standard call frame for the target. GDB keeps going - until one of 2 things happen @b{#1} an invalid frame is found, or @b{#2} some huge number of stackframes have been processed. By pushing zeros on the stack, GDB gracefully stops. @b{Debugging Interrupt Service Routines} - In your ISR before you call your C code, do the same - artifically push some zeros onto the stack, remember to pop them off when the ISR is done. @b{Also note:} If you have a multi-threaded operating system, they often do not @b{in the intrest of saving memory} waste these few bytes. Painful... @item @b{JTAG Reset Config} I get the following message in the OpenOCD console (or log file): "Warning: arm7_9_common.c:679 arm7_9_assert_reset(): srst resets test logic, too". This warning doesn't indicate any serious problem, as long as you don't want to debug your core right out of reset. Your .cfg file specified @option{jtag_reset trst_and_srst srst_pulls_trst} to tell OpenOCD that either your board, your debugger or your target uC (e.g. LPC2000) can't assert the two reset signals independently. With this setup, it's not possible to halt the core right out of reset, everything else should work fine. @item @b{USB Power} When using OpenOCD in conjunction with Amontec JTAGkey and the Yagarto toolchain (Eclipse, arm-elf-gcc, arm-elf-gdb), the debugging seems to be unstable. When single-stepping over large blocks of code, GDB and OpenOCD quit with an error message. Is there a stability issue with OpenOCD? No, this is not a stability issue concerning OpenOCD. Most users have solved this issue by simply using a self-powered USB hub, which they connect their Amontec JTAGkey to. Apparently, some computers do not provide a USB power supply stable enough for the Amontec JTAGkey to be operated. @b{Laptops running on battery have this problem too...} @item @b{USB Power} When using the Amontec JTAGkey, sometimes OpenOCD crashes with the following error messages: "Error: ft2232.c:201 ft2232_read(): FT_Read returned: 4" and "Error: ft2232.c:365 ft2232_send_and_recv(): couldn't read from FT2232". What does that mean and what might be the reason for this? First of all, the reason might be the USB power supply. Try using a self-powered hub instead of a direct connection to your computer. Secondly, the error code 4 corresponds to an FT_IO_ERROR, which means that the driver for the FTDI USB chip ran into some sort of error - this points us to a USB problem. @item @b{GDB Disconnects} When using the Amontec JTAGkey, sometimes OpenOCD crashes with the following error message: "Error: gdb_server.c:101 gdb_get_char(): read: 10054". What does that mean and what might be the reason for this? Error code 10054 corresponds to WSAECONNRESET, which means that the debugger (GDB) has closed the connection to OpenOCD. This might be a GDB issue. @item @b{LPC2000 Flash} In the configuration file in the section where flash device configurations are described, there is a parameter for specifying the clock frequency for LPC2000 internal flash devices (e.g. @option{flash bank lpc2000 0x0 0x40000 0 0 0 lpc2000_v1 14746 calc_checksum}), which must be specified in kilohertz. However, I do have a quartz crystal of a frequency that contains fractions of kilohertz (e.g. 14,745,600 Hz, i.e. 14,745.600 kHz). Is it possible to specify real numbers for the clock frequency? No. The clock frequency specified here must be given as an integral number. However, this clock frequency is used by the In-Application-Programming (IAP) routines of the LPC2000 family only, which seems to be very tolerant concerning the given clock frequency, so a slight difference between the specified clock frequency and the actual clock frequency will not cause any trouble. @item @b{Command Order} Do I have to keep a specific order for the commands in the configuration file? Well, yes and no. Commands can be given in arbitrary order, yet the devices listed for the JTAG scan chain must be given in the right order (jtag newdevice), with the device closest to the TDO-Pin being listed first. In general, whenever objects of the same type exist which require an index number, then these objects must be given in the right order (jtag newtap, targets and flash banks - a target references a jtag newtap and a flash bank references a target). You can use the ``scan_chain'' command to verify and display the tap order. Also, some commands can't execute until after @command{init} has been processed. Such commands include @command{nand probe} and everything else that needs to write to controller registers, perhaps for setting up DRAM and loading it with code. @item @b{JTAG Tap Order} JTAG tap order - command order Many newer devices have multiple JTAG taps. For example: ST Microsystems STM32 chips have two taps, a ``boundary scan tap'' and ``Cortex-M3'' tap. Example: The STM32 reference manual, Document ID: RM0008, Section 26.5, Figure 259, page 651/681, the ``TDI'' pin is connected to the boundary scan tap, which then connects to the Cortex-M3 tap, which then connects to the TDO pin. Thus, the proper order for the STM32 chip is: (1) The Cortex-M3, then (2) The boundary scan tap. If your board includes an additional JTAG chip in the scan chain (for example a Xilinx CPLD or FPGA) you could place it before or after the STM32 chip in the chain. For example: @itemize @bullet @item OpenOCD_TDI(output) -> STM32 TDI Pin (BS Input) @item STM32 BS TDO (output) -> STM32 Cortex-M3 TDI (input) @item STM32 Cortex-M3 TDO (output) -> SM32 TDO Pin @item STM32 TDO Pin (output) -> Xilinx TDI Pin (input) @item Xilinx TDO Pin -> OpenOCD TDO (input) @end itemize The ``jtag device'' commands would thus be in the order shown below. Note: @itemize @bullet @item jtag newtap Xilinx tap -irlen ... @item jtag newtap stm32 cpu -irlen ... @item jtag newtap stm32 bs -irlen ... @item # Create the debug target and say where it is @item target create stm32.cpu -chain-position stm32.cpu ... @end itemize @item @b{SYSCOMP} Sometimes my debugging session terminates with an error. When I look into the log file, I can see these error messages: Error: arm7_9_common.c:561 arm7_9_execute_sys_speed(): timeout waiting for SYSCOMP TODO. @end enumerate @node Tcl Crash Course @chapter Tcl Crash Course @cindex Tcl Not everyone knows Tcl - this is not intended to be a replacement for learning Tcl, the intent of this chapter is to give you some idea of how the Tcl scripts work. This chapter is written with two audiences in mind. (1) OpenOCD users who need to understand a bit more of how JIM-Tcl works so they can do something useful, and (2) those that want to add a new command to OpenOCD. @section Tcl Rule #1 There is a famous joke, it goes like this: @enumerate @item Rule #1: The wife is always correct @item Rule #2: If you think otherwise, See Rule #1 @end enumerate The Tcl equal is this: @enumerate @item Rule #1: Everything is a string @item Rule #2: If you think otherwise, See Rule #1 @end enumerate As in the famous joke, the consequences of Rule #1 are profound. Once you understand Rule #1, you will understand Tcl. @section Tcl Rule #1b There is a second pair of rules. @enumerate @item Rule #1: Control flow does not exist. Only commands @* For example: the classic FOR loop or IF statement is not a control flow item, they are commands, there is no such thing as control flow in Tcl. @item Rule #2: If you think otherwise, See Rule #1 @* Actually what happens is this: There are commands that by convention, act like control flow key words in other languages. One of those commands is the word ``for'', another command is ``if''. @end enumerate @section Per Rule #1 - All Results are strings Every Tcl command results in a string. The word ``result'' is used deliberatly. No result is just an empty string. Remember: @i{Rule #1 - Everything is a string} @section Tcl Quoting Operators In life of a Tcl script, there are two important periods of time, the difference is subtle. @enumerate @item Parse Time @item Evaluation Time @end enumerate The two key items here are how ``quoted things'' work in Tcl. Tcl has three primary quoting constructs, the [square-brackets] the @{curly-braces@} and ``double-quotes'' By now you should know $VARIABLES always start with a $DOLLAR sign. BTW: To set a variable, you actually use the command ``set'', as in ``set VARNAME VALUE'' much like the ancient BASIC langauge ``let x = 1'' statement, but without the equal sign. @itemize @bullet @item @b{[square-brackets]} @* @b{[square-brackets]} are command substitutions. It operates much like Unix Shell `back-ticks`. The result of a [square-bracket] operation is exactly 1 string. @i{Remember Rule #1 - Everything is a string}. These two statements are roughly identical: @example # bash example X=`date` echo "The Date is: $X" # Tcl example set X [date] puts "The Date is: $X" @end example @item @b{``double-quoted-things''} @* @b{``double-quoted-things''} are just simply quoted text. $VARIABLES and [square-brackets] are expanded in place - the result however is exactly 1 string. @i{Remember Rule #1 - Everything is a string} @example set x "Dinner" puts "It is now \"[date]\", $x is in 1 hour" @end example @item @b{@{Curly-Braces@}} @*@b{@{Curly-Braces@}} are magic: $VARIABLES and [square-brackets] are parsed, but are NOT expanded or executed. @{Curly-Braces@} are like 'single-quote' operators in BASH shell scripts, with the added feature: @{curly-braces@} can be nested, single quotes can not. @{@{@{this is nested 3 times@}@}@} NOTE: [date] is perhaps a bad example, as of 28/nov/2008, Jim/OpenOCD does not have a date command. @end itemize @section Consequences of Rule 1/2/3/4 The consequences of Rule 1 are profound. @subsection Tokenisation & Execution. Of course, whitespace, blank lines and #comment lines are handled in the normal way. As a script is parsed, each (multi) line in the script file is tokenised and according to the quoting rules. After tokenisation, that line is immedatly executed. Multi line statements end with one or more ``still-open'' @{curly-braces@} which - eventually - closes a few lines later. @subsection Command Execution Remember earlier: There are no ``control flow'' statements in Tcl. Instead there are COMMANDS that simply act like control flow operators. Commands are executed like this: @enumerate @item Parse the next line into (argc) and (argv[]). @item Look up (argv[0]) in a table and call its function. @item Repeat until End Of File. @end enumerate It sort of works like this: @example for(;;)@{ ReadAndParse( &argc, &argv ); cmdPtr = LookupCommand( argv[0] ); (*cmdPtr->Execute)( argc, argv ); @} @end example When the command ``proc'' is parsed (which creates a procedure function) it gets 3 parameters on the command line. @b{1} the name of the proc (function), @b{2} the list of parameters, and @b{3} the body of the function. Not the choice of words: LIST and BODY. The PROC command stores these items in a table somewhere so it can be found by ``LookupCommand()'' @subsection The FOR command The most interesting command to look at is the FOR command. In Tcl, the FOR command is normally implemented in C. Remember, FOR is a command just like any other command. When the ascii text containing the FOR command is parsed, the parser produces 5 parameter strings, @i{(If in doubt: Refer to Rule #1)} they are: @enumerate 0 @item The ascii text 'for' @item The start text @item The test expression @item The next text @item The body text @end enumerate Sort of reminds you of ``main( int argc, char **argv )'' does it not? Remember @i{Rule #1 - Everything is a string.} The key point is this: Often many of those parameters are in @{curly-braces@} - thus the variables inside are not expanded or replaced until later. Remember that every Tcl command looks like the classic ``main( argc, argv )'' function in C. In JimTCL - they actually look like this: @example int MyCommand( Jim_Interp *interp, int *argc, Jim_Obj * const *argvs ); @end example Real Tcl is nearly identical. Although the newer versions have introduced a byte-code parser and intepreter, but at the core, it still operates in the same basic way. @subsection FOR command implementation To understand Tcl it is perhaps most helpful to see the FOR command. Remember, it is a COMMAND not a control flow structure. In Tcl there are two underlying C helper functions. Remember Rule #1 - You are a string. The @b{first} helper parses and executes commands found in an ascii string. Commands can be seperated by semicolons, or newlines. While parsing, variables are expanded via the quoting rules. The @b{second} helper evaluates an ascii string as a numerical expression and returns a value. Here is an example of how the @b{FOR} command could be implemented. The pseudo code below does not show error handling. @example void Execute_AsciiString( void *interp, const char *string ); int Evaluate_AsciiExpression( void *interp, const char *string ); int MyForCommand( void *interp, int argc, char **argv ) @{ if( argc != 5 )@{ SetResult( interp, "WRONG number of parameters"); return ERROR; @} // argv[0] = the ascii string just like C // Execute the start statement. Execute_AsciiString( interp, argv[1] ); // Top of loop test for(;;)@{ i = Evaluate_AsciiExpression(interp, argv[2]); if( i == 0 ) break; // Execute the body Execute_AsciiString( interp, argv[3] ); // Execute the LOOP part Execute_AsciiString( interp, argv[4] ); @} // Return no error SetResult( interp, "" ); return SUCCESS; @} @end example Every other command IF, WHILE, FORMAT, PUTS, EXPR, everything works in the same basic way. @section OpenOCD Tcl Usage @subsection source and find commands @b{Where:} In many configuration files @* Example: @b{ source [find FILENAME] } @*Remember the parsing rules @enumerate @item The FIND command is in square brackets. @* The FIND command is executed with the parameter FILENAME. It should find the full path to the named file. The RESULT is a string, which is substituted on the orginal command line. @item The command source is executed with the resulting filename. @* SOURCE reads a file and executes as a script. @end enumerate @subsection format command @b{Where:} Generally occurs in numerous places. @* Tcl has no command like @b{printf()}, instead it has @b{format}, which is really more like @b{sprintf()}. @b{Example} @example set x 6 set y 7 puts [format "The answer: %d" [expr $x * $y]] @end example @enumerate @item The SET command creates 2 variables, X and Y. @item The double [nested] EXPR command performs math @* The EXPR command produces numerical result as a string. @* Refer to Rule #1 @item The format command is executed, producing a single string @* Refer to Rule #1. @item The PUTS command outputs the text. @end enumerate @subsection Body or Inlined Text @b{Where:} Various TARGET scripts. @example #1 Good proc someproc @{@} @{ ... multiple lines of stuff ... @} $_TARGETNAME configure -event FOO someproc #2 Good - no variables $_TARGETNAME confgure -event foo "this ; that;" #3 Good Curly Braces $_TARGETNAME configure -event FOO @{ puts "Time: [date]" @} #4 DANGER DANGER DANGER $_TARGETNAME configure -event foo "puts \"Time: [date]\"" @end example @enumerate @item The $_TARGETNAME is an OpenOCD variable convention. @*@b{$_TARGETNAME} represents the last target created, the value changes each time a new target is created. Remember the parsing rules. When the ascii text is parsed, the @b{$_TARGETNAME} becomes a simple string, the name of the target which happens to be a TARGET (object) command. @item The 2nd parameter to the @option{-event} parameter is a TCBODY @*There are 4 examples: @enumerate @item The TCLBODY is a simple string that happens to be a proc name @item The TCLBODY is several simple commands seperated by semicolons @item The TCLBODY is a multi-line @{curly-brace@} quoted string @item The TCLBODY is a string with variables that get expanded. @end enumerate In the end, when the target event FOO occurs the TCLBODY is evaluated. Method @b{#1} and @b{#2} are functionally identical. For Method @b{#3} and @b{#4} it is more interesting. What is the TCLBODY? Remember the parsing rules. In case #3, @{curly-braces@} mean the $VARS and [square-brackets] are expanded later, when the EVENT occurs, and the text is evaluated. In case #4, they are replaced before the ``Target Object Command'' is executed. This occurs at the same time $_TARGETNAME is replaced. In case #4 the date will never change. @{BTW: [date] is perhaps a bad example, as of 28/nov/2008, Jim/OpenOCD does not have a date command@} @end enumerate @subsection Global Variables @b{Where:} You might discover this when writing your own procs @* In simple terms: Inside a PROC, if you need to access a global variable you must say so. See also ``upvar''. Example: @example proc myproc @{ @} @{ set y 0 #Local variable Y global x #Global variable X puts [format "X=%d, Y=%d" $x $y] @} @end example @section Other Tcl Hacks @b{Dynamic variable creation} @example # Dynamically create a bunch of variables. for @{ set x 0 @} @{ $x < 32 @} @{ set x [expr $x + 1]@} @{ # Create var name set vn [format "BIT%d" $x] # Make it a global global $vn # Set it. set $vn [expr (1 << $x)] @} @end example @b{Dynamic proc/command creation} @example # One "X" function - 5 uart functions. foreach who @{A B C D E@} proc [format "show_uart%c" $who] @{ @} "show_UARTx $who" @} @end example @node Target Library @chapter Target Library @cindex Target Library OpenOCD comes with a target configuration script library. These scripts can be used as-is or serve as a starting point. The target library is published together with the OpenOCD executable and the path to the target library is in the OpenOCD script search path. Similarly there are example scripts for configuring the JTAG interface. The command line below uses the example parport configuration script that ship with OpenOCD, then configures the str710.cfg target and finally issues the init and reset commands. The communication speed is set to 10kHz for reset and 8MHz for post reset. @example openocd -f interface/parport.cfg -f target/str710.cfg \ -c "init" -c "reset" @end example To list the target scripts available: @example $ ls /usr/local/lib/openocd/target arm7_fast.cfg lm3s6965.cfg pxa255.cfg stm32.cfg xba_revA3.cfg at91eb40a.cfg lpc2148.cfg pxa255_sst.cfg str710.cfg zy1000.cfg at91r40008.cfg lpc2294.cfg sam7s256.cfg str912.cfg at91sam9260.cfg nslu2.cfg sam7x256.cfg wi-9c.cfg @end example @include fdl.texi @node OpenOCD Concept Index @comment DO NOT use the plain word ``Index'', reason: CYGWIN filename @comment case issue with ``Index.html'' and ``index.html'' @comment Occurs when creating ``--html --no-split'' output @comment This fix is based on: http://sourceware.org/ml/binutils/2006-05/msg00215.html @unnumbered OpenOCD Concept Index @printindex cp @node Command and Driver Index @unnumbered Command and Driver Index @printindex fn @bye