ARM7/ARM9: remove old "debug commands"

Remove two commands that were documented as "debug commands"
and where "you probably don't want to use this".   We never
intended to support them, and at least one problem report
boiled down to using this when it shouldn't have been used.

Update the docs on the existing register commands to talk a
bit more about register access and cache behavior.  (Those
debug commands existed largely to *bypass* the cache.)  And
fix some minor doc goofs that snuck in with recent changes,
renaming "armv4_5" as "arm" and "arm9tdmi" as "arm9".

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>

2 files changed, 35 insertions, 182 deletions

diff --git a/doc/openocd.texi b/doc/openocd.texi
index 0253dc0d..9659e929 100644
--- a/doc/openocd.texi
+++ b/doc/openocd.texi
@@ -4933,26 +4933,37 @@ target which should become current.
 
 @deffn Command reg [(number|name) [value]]
 Access a single register by @var{number} or by its @var{name}.
+The target must generally be halted before access to CPU core
+registers is allowed.  Depending on the hardware, some other
+registers may be accessible while the target is running.
 
 @emph{With no arguments}:
 list all available registers for the current target,
 showing number, name, size, value, and cache status.
+For valid entries, a value is shown; valid entries
+which are also dirty (and will be written back later)
+are flagged as such.
 
 @emph{With number/name}: display that register's value.
 
 @emph{With both number/name and value}: set register's value.
+Writes may be held in a writeback cache internal to OpenOCD,
+so that setting the value marks the register as dirty instead
+of immediately flushing that value.  Resuming CPU execution
+(including by single stepping) or otherwise activating the
+relevant module will flush such values.
 
 Cores may have surprisingly many registers in their
 Debug and trace infrastructure:
 
 @example
 > reg
-(0) r0 (/32): 0x0000D3C2 (dirty: 1, valid: 1)
-(1) r1 (/32): 0xFD61F31C (dirty: 0, valid: 1)
-(2) r2 (/32): 0x00022551 (dirty: 0, valid: 1)
+===== ARM registers
+(0) r0 (/32): 0x0000D3C2 (dirty)
+(1) r1 (/32): 0xFD61F31C
+(2) r2 (/32)
 ...
-(164) ETM_CONTEXTID_COMPARATOR_MASK (/32): \
-              0x00000000 (dirty: 0, valid: 0)
+(164) ETM_contextid_comparator_mask (/32)
 >
 @end example
 @end deffn
@@ -5554,17 +5565,25 @@ ThumbEE disassembly currently has no explicit support.
 
 @deffn Command {arm reg}
 Display a table 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.
+core mode if necessary.
 @end deffn
 
+@section ARMv4 and ARMv5 Architecture
+@cindex ARMv4
+@cindex ARMv5
+
+The ARMv4 and ARMv5 architectures are widely used in embedded systems,
+and introduced core parts of the instruction set in use today. 
+That includes the Thumb instruction set, introduced in the ARMv4T
+variant.
+
 @subsection ARM7 and ARM9 specific commands
 @cindex ARM7
 @cindex ARM9
 
 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,
+They are available in addition to the ARM commands,
 and any other core-specific commands that may be available.
 
 @deffn Command {arm7_9 dbgrq} (@option{enable}|@option{disable})
@@ -5591,49 +5610,13 @@ 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 (@option{0}|@option{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 (@option{0}|@option{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
 
 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.
+They are available in addition to the ARM and ARM7/ARM9 commands.
 
 @deffn Command {arm720t cp15} regnum [value]
 Display cp15 register @var{regnum};
@@ -5677,8 +5660,8 @@ or a list with one or more of the following:
 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.
+They are available in addition to the ARM, ARM7/ARM9,
+and ARM9 commands.
 
 @deffn Command {arm920t cache_info}
 Print information about the caches found. This allows to see whether your target
@@ -5711,8 +5694,8 @@ Dump the content of the ITLB and DTLB to a file named @file{filename}.
 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.
+They are available in addition to the ARM, ARM7/ARM9,
+and ARM9 commands.
 
 The Feroceon cores also support these commands, although
 they are not built from ARM926ej-s designs.
@@ -5733,8 +5716,8 @@ Else that register is read and displayed.
 
 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.
+They are available in addition to the ARM, ARM7/ARM9,
+and ARM9 commands.
 
 @deffn Command {arm966e cp15} regnum [value]
 Display cp15 register @var{regnum};
@@ -5926,7 +5909,7 @@ cores @emph{except the ARM1176} use the same six bits.
 @cindex Debug Access Port
 @cindex DAP
 These commands are specific to ARM architecture v7 Debug Access Port (DAP),
-included on cortex-m3 and cortex-a8 systems.
+included on Cortex-M3 and Cortex-A8 systems.
 They are available in addition to other core-specific commands that may be available.
 
 @deffn Command {dap info} [num]
diff --git a/src/target/arm7_9_common.c b/src/target/arm7_9_common.c
index 1c854177..7a2b5429 100644
--- a/src/target/arm7_9_common.c
+++ b/src/target/arm7_9_common.c
@@ -2737,124 +2737,6 @@ int arm7_9_examine(struct target *target)
 	return retval;
 }
 
-
-COMMAND_HANDLER(handle_arm7_9_write_xpsr_command)
-{
-	uint32_t value;
-	int spsr;
-	int retval;
-	struct target *target = get_current_target(CMD_CTX);
-	struct arm7_9_common *arm7_9 = target_to_arm7_9(target);
-
-	if (!is_arm7_9(arm7_9))
-	{
-		command_print(CMD_CTX, "current target isn't an ARM7/ARM9 target");
-		return ERROR_TARGET_INVALID;
-	}
-
-	if (target->state != TARGET_HALTED)
-	{
-		command_print(CMD_CTX, "can't write registers while running");
-		return ERROR_FAIL;
-	}
-
-	if (CMD_ARGC < 2)
-	{
-		command_print(CMD_CTX, "usage: write_xpsr <value> <not cpsr | spsr>");
-		return ERROR_FAIL;
-	}
-
-	COMMAND_PARSE_NUMBER(u32, CMD_ARGV[0], value);
-	COMMAND_PARSE_NUMBER(int, CMD_ARGV[1], spsr);
-
-	/* if we're writing the CPSR, mask the T bit */
-	if (!spsr)
-		value &= ~0x20;
-
-	arm7_9->write_xpsr(target, value, spsr);
-	if ((retval = jtag_execute_queue()) != ERROR_OK)
-	{
-		LOG_ERROR("JTAG error while writing to xpsr");
-		return retval;
-	}
-
-	return ERROR_OK;
-}
-
-COMMAND_HANDLER(handle_arm7_9_write_xpsr_im8_command)
-{
-	uint32_t value;
-	int rotate;
-	int spsr;
-	int retval;
-	struct target *target = get_current_target(CMD_CTX);
-	struct arm7_9_common *arm7_9 = target_to_arm7_9(target);
-
-	if (!is_arm7_9(arm7_9))
-	{
-		command_print(CMD_CTX, "current target isn't an ARM7/ARM9 target");
-		return ERROR_TARGET_INVALID;
-	}
-
-	if (target->state != TARGET_HALTED)
-	{
-		command_print(CMD_CTX, "can't write registers while running");
-		return ERROR_FAIL;
-	}
-
-	if (CMD_ARGC < 3)
-	{
-		command_print(CMD_CTX, "usage: write_xpsr_im8 <im8> <rotate> <not cpsr | spsr>");
-		return ERROR_FAIL;
-	}
-
-	COMMAND_PARSE_NUMBER(u32, CMD_ARGV[0], value);
-	COMMAND_PARSE_NUMBER(int, CMD_ARGV[1], rotate);
-	COMMAND_PARSE_NUMBER(int, CMD_ARGV[2], spsr);
-
-	arm7_9->write_xpsr_im8(target, value, rotate, spsr);
-	if ((retval = jtag_execute_queue()) != ERROR_OK)
-	{
-		LOG_ERROR("JTAG error while writing 8-bit immediate to xpsr");
-		return retval;
-	}
-
-	return ERROR_OK;
-}
-
-COMMAND_HANDLER(handle_arm7_9_write_core_reg_command)
-{
-	uint32_t value;
-	uint32_t mode;
-	int num;
-	struct target *target = get_current_target(CMD_CTX);
-	struct arm7_9_common *arm7_9 = target_to_arm7_9(target);
-
-	if (!is_arm7_9(arm7_9))
-	{
-		command_print(CMD_CTX, "current target isn't an ARM7/ARM9 target");
-		return ERROR_TARGET_INVALID;
-	}
-
-	if (target->state != TARGET_HALTED)
-	{
-		command_print(CMD_CTX, "can't write registers while running");
-		return ERROR_FAIL;
-	}
-
-	if (CMD_ARGC < 3)
-	{
-		command_print(CMD_CTX, "usage: write_core_reg <num> <mode> <value>");
-		return ERROR_FAIL;
-	}
-
-	COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], num);
-	COMMAND_PARSE_NUMBER(u32, CMD_ARGV[1], mode);
-	COMMAND_PARSE_NUMBER(u32, CMD_ARGV[2], value);
-
-	return arm7_9_write_core_reg(target, num, mode, value);
-}
-
 COMMAND_HANDLER(handle_arm7_9_dbgrq_command)
 {
 	struct target *target = get_current_target(CMD_CTX);
@@ -2948,18 +2830,6 @@ int arm7_9_register_commands(struct command_context *cmd_ctx)
 	arm7_9_cmd = register_command(cmd_ctx, NULL, "arm7_9",
 			NULL, COMMAND_ANY, "arm7/9 specific commands");
 
-	register_command(cmd_ctx, arm7_9_cmd, "write_xpsr",
-			handle_arm7_9_write_xpsr_command, COMMAND_EXEC,
-			"write program status register <value> <not cpsr | spsr>");
-	register_command(cmd_ctx, arm7_9_cmd, "write_xpsr_im8",
-			handle_arm7_9_write_xpsr_im8_command, COMMAND_EXEC,
-			"write program status register "
-			"<8bit immediate> <rotate> <not cpsr | spsr>");
-
-	register_command(cmd_ctx, arm7_9_cmd, "write_core_reg",
-			handle_arm7_9_write_core_reg_command, COMMAND_EXEC,
-			"write core register <num> <mode> <value>");
-
 	register_command(cmd_ctx, arm7_9_cmd, "dbgrq",
 			handle_arm7_9_dbgrq_command, COMMAND_ANY,
 			"use EmbeddedICE dbgrq instead of breakpoint "