From 7f2221958dbc6bda0e51df87e80aa5a9c5140914 Mon Sep 17 00:00:00 2001 From: Tomek CEDRO Date: Thu, 16 Jun 2011 08:13:07 +0000 Subject: FT2232_DRIVER: Added bitbang() implementation backend to drive signals on FT2*32 chip. --- src/jtag/drivers/ft2232.c | 107 ++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 104 insertions(+), 3 deletions(-) (limited to 'src') diff --git a/src/jtag/drivers/ft2232.c b/src/jtag/drivers/ft2232.c index 38ead566..d16d4d6a 100644 --- a/src/jtag/drivers/ft2232.c +++ b/src/jtag/drivers/ft2232.c @@ -1,9 +1,9 @@ -/*************************************************************************** +/************************************************************************** * Copyright (C) 2009 by Øyvind Harboe * -* Øyvind Harboe * +* Øyvind Harboe * * * * Copyright (C) 2009 by SoftPLC Corporation. http://softplc.com * -* Dick Hollenbeck * +* Dick Hollenbeck * * * * Copyright (C) 2004, 2006 by Dominic Rath * * Dominic.Rath@gmx.de * @@ -11,6 +11,9 @@ * Copyright (C) 2008 by Spencer Oliver * * spen@spen-soft.co.uk * * * +* Copyright (C) 2011 Tomasz Boleslaw CEDRO * +* cederom@tlen.pl, http://www.tomek.cedro.info * +* * * This program is free software; you can redistribute it and/or modify * * it under the terms of the GNU General Public License as published by * * the Free Software Foundation; either version 2 of the License, or * @@ -81,6 +84,7 @@ /* project specific includes */ #include +#include #include #include @@ -594,6 +598,102 @@ static int ft2232_read(uint8_t* buf, uint32_t size, uint32_t* bytes_read) return ERROR_OK; } +/** Generic IO BITBANG Port Manipulation Routine. + * It can read and write port state using signal names. Each interface have its + * own specific signal names and fields. This function works on those fields + * and based on their values talks to the FT*232 chip on the interface device. + * ft2232 drivers use {low,high}_{output,direction} global variables to remember + * port direction and value, so we need to work on them as well not to change + * any other pin with our bit-baning performed only on selected pins. + * The function name 'bitbang' reflects ability to change selected pin states. + * + * @Note: FT2232 has special mechanism called MPSSE for serial communications + * that is far more efficient than pure 'bitbang' mode on this device family. + * Although our function is named 'bitbang' it does not use bitbang mode. + * MPSSE command send value and port bytes on port write, but does not on read. + * This happens every time we want to change pin value, so we need to use cache. + * On write we want to OR direction mask already set by init() procedure + * to mark bit-mask output. On read we want to clear bits given by mask + * to mark them input. To read we need to write/update port state first. + * Long story short: to read data we first need to set pins to input. + * + * @Warning: reading and writing will set pin direction input or output, + * so it is possible to disable basic data output pins with bad masking, + * but also gives chance to create and manage full TCL signal description, + * that can be used to take advantage of some additional interface hardware + * features installed on some devices (i.e. ADC, power supply, etc). + * This gives new way of signal handling that is still backward-compatible. + * + * \param *device void pointer to pass additional driver information to the routine. + * \param signal is the string representation of the signal mask stored in layout structure. + * \param GETnSET if zero then perform read operation, write otherwise. + * \param *value is the pointer that holds the value. + * \return ERROR_OK on success, or ERROR_FAIL on failure. + */ +int ft2232_bitbang(void *device, char *signal_name, int GETnSET, int *value){ + uint8_t buf[3]; + int retval, vall=0, valh=0; + unsigned int sigmask; + uint32_t bytes_written, bytes_read; + oocd_interface_signal_t *sig; + + //First get the signal mask, or return error if signal not defined. + if (!(sig=oocd_interface_signal_find(signal_name))){ + LOG_ERROR("Requested signal not found on this interface!"); + return ERROR_FAIL; + } + // Pin mask is also related with port direction and complicates it!!! + sigmask=sig->mask; + + if (!GETnSET){ + // We will SET port pins selected by sigmask. + // Modify our pins value, but remember about other pins and their previous value + low_output = (low_output & ~sigmask) | ((*value & sigmask) & 0x0ff); + high_output = (high_output & ~(sigmask>>8)) | (((*value & sigmask)>>8) & 0x0ff); + // Modify our pins direction, but remember about other pins and their previous direction + low_direction |= sigmask & 0x0ff; + high_direction |= (sigmask>>8) & 0x0ff; + // Now send those settings to the interface chip + buf[0] = 0x80; //Set Data Bits LowByte + buf[1] = low_output; + buf[2] = low_direction; + if ((retval=ft2232_write(buf, 3, &bytes_written)) != ERROR_OK) return retval; + buf[0] = 0x82; //Set Data Bits HighByte + buf[1] = high_output; + buf[2] = high_direction; + if ((retval=ft2232_write(buf, 3, &bytes_written)) != ERROR_OK) return retval; + sig->value = ((high_output<<8) | low_output) & sig->mask; + } else { + // Modify our pins value, but remember about other pins and their previous value + // DO WE REALLY NEED TO PULL-UP PINS TO READ THEIR STATE OR SIMPLY LEAVE AS IS? + //low_output = (low_output & ~sigmask) | (sigmask & 0x0ff); + //high_output = (high_output & ~sigmask) | (sigmask>>8) & 0x0ff); + // Modify our pins direction to input, but remember about other pins and their previous direction + low_direction &= ~(sigmask); + high_direction &= ~(sigmask>>8); + // Now send those settings to the interface chip + // First change desired pins to input + buf[0] = 0x80; //Set Data Bits LowByte + buf[1] = low_output; + buf[2] = low_direction; + if ((retval=ft2232_write(buf, 3, &bytes_written)) != ERROR_OK) return retval; + buf[0] = 0x82; //Set Data Bits HighByte + buf[1] = high_output; + buf[2] = high_direction; + if ((retval=ft2232_write(buf, 3, &bytes_written)) != ERROR_OK) return retval; + // Then read pins designated by a signal mask + buf[0]=0x81; //Read Data Bits LowByte. + if ((retval=ft2232_write(buf, 1, &bytes_written)) != ERROR_OK) return retval; + if ((retval=ft2232_read((uint8_t *)&vall, 1, &bytes_read)) != ERROR_OK) return retval; + buf[0]=0x83; //Read Data Bits HighByte. + if ((retval=ft2232_write(buf, 1, &bytes_written)) != ERROR_OK) return retval; + if ((retval=ft2232_read((uint8_t *)&valh, 1, &bytes_read)) != ERROR_OK) return retval; + sig->value = *value = ((valh<<8)|vall) & sig->mask; //Join result bytes and apply signal bitmask + } + return ERROR_OK; +} + + static bool ft2232_device_is_highspeed(void) { #if BUILD_FT2232_FTD2XX == 1 @@ -4486,4 +4586,5 @@ struct jtag_interface ft2232_interface = { .speed_div = ft2232_speed_div, .khz = ft2232_khz, .execute_queue = ft2232_execute_queue, + .bitbang = ft2232_bitbang, }; -- cgit v1.2.3