- Fixed display of sector sizes in flash.c

- Clean up, remove unused variables and code in armv7, cortex_m3 and stellaris code 
- Move restore_context from cortex_m3 to armv7m
- Updated halt handling for cortex_m3


git-svn-id: svn://svn.berlios.de/openocd/trunk@206 b42882b7-edfa-0310-969c-e2dbd0fdcd60

7 files changed, 127 insertions, 107 deletions

diff --git a/src/flash/flash.c b/src/flash/flash.c
index 9ca5f157..83b6fc37 100644
--- a/src/flash/flash.c
+++ b/src/flash/flash.c
@@ -267,8 +267,8 @@ int handle_flash_info_command(struct command_context_s *cmd_ctx, char *cmd, char
 				else
 					protect_state = "protection state unknown";
 
-				command_print(cmd_ctx, "\t#%i: 0x%8.8x (0x%xkB) %s, %s",
-							j, p->sectors[j].offset, p->sectors[j].size,
+				command_print(cmd_ctx, "\t#%i: 0x%8.8x (0x%x %ikB) %s, %s",
+							j, p->sectors[j].offset, p->sectors[j].size, p->sectors[j].size>>10,
 							erase_state, protect_state);
 			}
 			
diff --git a/src/flash/stellaris.c b/src/flash/stellaris.c
index 490b02cc..970c1d69 100644
--- a/src/flash/stellaris.c
+++ b/src/flash/stellaris.c
@@ -43,6 +43,7 @@
 #include <string.h>
 #include <unistd.h>
 
+#define DID0_VER(did0) ((did0>>28)&0x07)
 int stellaris_register_commands(struct command_context_s *cmd_ctx);
 int stellaris_flash_bank_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc, struct flash_bank_s *bank);
 int stellaris_erase(struct flash_bank_s *bank, int first, int last);
@@ -53,6 +54,7 @@ int stellaris_erase_check(struct flash_bank_s *bank);
 int stellaris_protect_check(struct flash_bank_s *bank);
 int stellaris_info(struct flash_bank_s *bank, char *buf, int buf_size);
 
+int stellaris_read_part_info(struct flash_bank_s *bank);
 u32 stellaris_get_flash_status(flash_bank_t *bank);
 void stellaris_set_flash_mode(flash_bank_t *bank,int mode);
 u32 stellaris_wait_status_busy(flash_bank_t *bank, u32 waitbits, int timeout);
@@ -128,6 +130,12 @@ struct {
 	{0,"Unknown part"}
 };
 
+char * StellarisClassname[2] =
+{
+	"Sandstorm",
+	"Fury"
+};
+
 /***************************************************************************
 *	openocd command interface                                              *
 ***************************************************************************/
@@ -169,7 +177,7 @@ int stellaris_register_commands(struct command_context_s *cmd_ctx)
 
 int stellaris_info(struct flash_bank_s *bank, char *buf, int buf_size)
 {
-	int printed;
+	int printed, device_class;
 	stellaris_flash_bank_t *stellaris_info = bank->driver_priv;
 	
 	stellaris_read_part_info(bank);
@@ -182,8 +190,16 @@ int stellaris_info(struct flash_bank_s *bank, char *buf, int buf_size)
 		return ERROR_FLASH_OPERATION_FAILED;
 	}
 	
-    printed = snprintf(buf, buf_size, "\nLMI Stellaris information: Chip is class %i %s v%c.%i\n",
-         (stellaris_info->did0>>16)&0xff, stellaris_info->target_name,
+	if (DID0_VER(stellaris_info->did0)>0)
+	{
+		device_class = (stellaris_info->did0>>16)&0xFF;
+	}
+	else
+	{
+		device_class = 0;
+	}	
+    printed = snprintf(buf, buf_size, "\nLMI Stellaris information: Chip is class %i(%s) %s v%c.%i\n",
+         device_class, StellarisClassname[device_class], stellaris_info->target_name,
          'A' + (stellaris_info->did0>>8)&0xFF, (stellaris_info->did0)&0xFF);
 	buf += printed;
 	buf_size -= printed;
@@ -211,7 +227,6 @@ int stellaris_info(struct flash_bank_s *bank, char *buf, int buf_size)
 
 u32 stellaris_get_flash_status(flash_bank_t *bank)
 {
-	stellaris_flash_bank_t *stellaris_info = bank->driver_priv;
 	target_t *target = bank->target;
 	u32 fmc;
 	
@@ -227,7 +242,7 @@ void stellaris_read_clock_info(flash_bank_t *bank)
 	stellaris_flash_bank_t *stellaris_info = bank->driver_priv;
 	target_t *target = bank->target;
 	u32 rcc, pllcfg, sysdiv, usesysdiv, bypass, oscsrc;
-	unsigned long tmp, mainfreq;
+	unsigned long mainfreq;
 
 	target_read_u32(target, SCB_BASE|RCC, &rcc);
 	DEBUG("Stellaris RCC %x",rcc);
@@ -302,7 +317,7 @@ u32 stellaris_wait_status_busy(flash_bank_t *bank, u32 waitbits, int timeout)
 int stellaris_flash_command(struct flash_bank_s *bank,u8 cmd,u16 pagen) 
 {
 	u32 fmc;
-	stellaris_flash_bank_t *stellaris_info = bank->driver_priv;
+//	stellaris_flash_bank_t *stellaris_info = bank->driver_priv;
 	target_t *target = bank->target;
 
 	fmc = FMC_WRKEY | cmd; 
@@ -336,8 +351,7 @@ int stellaris_read_part_info(struct flash_bank_s *bank)
     if((ver != 0) && (ver != 1))
 	{
         WARNING("Unknown did0 version, cannot identify target");
-		return ERROR_FLASH_OPERATION_FAILED;
-	
+		return ERROR_FLASH_OPERATION_FAILED;	
 	}
 
     ver = did1 >> 28;
@@ -363,7 +377,7 @@ int stellaris_read_part_info(struct flash_bank_s *bank)
 	
 	stellaris_info->did0 = did0;
 	stellaris_info->did1 = did1;
-	
+
 	stellaris_info->num_lockbits = 1+stellaris_info->dc0&0xFFFF;
 	stellaris_info->num_pages = 2*(1+stellaris_info->dc0&0xFFFF);
 	stellaris_info->pagesize = 1024;
@@ -376,8 +390,6 @@ int stellaris_read_part_info(struct flash_bank_s *bank)
 	
 	status = stellaris_get_flash_status(bank);
 	
-	WARNING("stellaris flash only tested for LM3S811 series");
-	
 	return ERROR_OK;
 }
 
@@ -387,11 +399,13 @@ int stellaris_read_part_info(struct flash_bank_s *bank)
 
 int stellaris_erase_check(struct flash_bank_s *bank)
 {
+	/* 
+	
 	stellaris_flash_bank_t *stellaris_info = bank->driver_priv;
 	target_t *target = bank->target;
 	int i;
 	
-	/* */
+	*/
 	
 	return ERROR_OK;
 }
@@ -401,7 +415,6 @@ int stellaris_protect_check(struct flash_bank_s *bank)
 	u32 status;
 	
 	stellaris_flash_bank_t *stellaris_info = bank->driver_priv;
-	target_t *target = bank->target;
 
 	if (stellaris_info->did1 == 0)
 	{
@@ -511,7 +524,7 @@ int stellaris_erase(struct flash_bank_s *bank, int first, int last)
 
 int stellaris_protect(struct flash_bank_s *bank, int set, int first, int last)
 {
-	u32 cmd, fmppe, flash_fmc, flash_cris;
+	u32 fmppe, flash_fmc, flash_cris;
 	int lockregion;
 	
 	stellaris_flash_bank_t *stellaris_info = bank->driver_priv;
@@ -586,15 +599,18 @@ int stellaris_protect(struct flash_bank_s *bank, int set, int first, int last)
 
 u8 stellaris_write_code[] = 
 {
-/* Call with :	
+/* 
+	Call with :	
 	r0 = buffer address
 	r1 = destination address
 	r2 = bytecount (in) - endaddr (work) 
+	
+	Used registers:	
 	r3 = pFLASH_CTRL_BASE
 	r4 = FLASHWRITECMD
 	r5 = #1
-	r6 = scratch
-	r7
+	r6 = bytes written
+	r7 = temp reg
 */
 	0x07,0x4B,     		/* ldr r3,pFLASH_CTRL_BASE */
 	0x08,0x4C,     		/* ldr r4,FLASHWRITECMD */
@@ -622,7 +638,7 @@ u8 stellaris_write_code[] =
 
 int stellaris_write_block(struct flash_bank_s *bank, u8 *buffer, u32 offset, u32 wcount)
 {
-	stellaris_flash_bank_t *stellaris_info = bank->driver_priv;
+//	stellaris_flash_bank_t *stellaris_info = bank->driver_priv;
 	target_t *target = bank->target;
 	u32 buffer_size = 8192;
 	working_area_t *source;
@@ -632,8 +648,8 @@ int stellaris_write_block(struct flash_bank_s *bank, u8 *buffer, u32 offset, u32
 	armv7m_algorithm_t armv7m_info;
 	int retval;
 	
-    DEBUG("(bank=%08X buffer=%08X offset=%08X wcount=%08X)",
-                                  bank, buffer, offset, wcount);
+	DEBUG("(bank=%08X buffer=%08X offset=%08X wcount=%08X)",
+			(unsigned int)bank, (unsigned int)buffer, offset, wcount);
 
 	/* flash write code */
 	if (target_alloc_working_area(target, sizeof(stellaris_write_code), &write_algorithm) != ERROR_OK)
@@ -647,8 +663,8 @@ int stellaris_write_block(struct flash_bank_s *bank, u8 *buffer, u32 offset, u32
 	/* memory buffer */
 	while (target_alloc_working_area(target, buffer_size, &source) != ERROR_OK)
 	{
-        DEBUG("called target_alloc_working_area(target=%08X buffer_size=%08X source=%08X)",
-                             target, buffer_size, source); 
+		DEBUG("called target_alloc_working_area(target=%08X buffer_size=%08X source=%08X)",
+				(unsigned int)target, buffer_size, (unsigned int)source); 
 		buffer_size /= 2;
 		if (buffer_size <= 256)
 		{
@@ -720,13 +736,12 @@ int stellaris_write(struct flash_bank_s *bank, u8 *buffer, u32 offset, u32 count
 {
 	stellaris_flash_bank_t *stellaris_info = bank->driver_priv;
 	target_t *target = bank->target;
-	u32 dst_min_alignment, wcount, bytes_remaining = count;
 	u32 address = offset;
-	u32 fcr,flash_cris,flash_fmc;
+	u32 flash_cris,flash_fmc;
 	u32 retval;
 	
-    DEBUG("(bank=%08X buffer=%08X offset=%08X count=%08X)",
-                            bank, buffer, offset, count);
+	DEBUG("(bank=%08X buffer=%08X offset=%08X count=%08X)",
+			(unsigned int)bank, (unsigned int)buffer, offset, count);
 
 	if (bank->target->state != TARGET_HALTED)
 	{
diff --git a/src/target/armv7m.c b/src/target/armv7m.c
index 5ab9c104..96864fd1 100644
--- a/src/target/armv7m.c
+++ b/src/target/armv7m.c
@@ -174,6 +174,33 @@ int armv7m_use_context(target_t *target, enum armv7m_runcontext new_ctx)
 	return ERROR_OK;
 }
 
+int armv7m_restore_context(target_t *target)
+{
+	int i;
+	
+	/* get pointers to arch-specific information */
+	armv7m_common_t *armv7m = target->arch_info;
+
+	DEBUG(" ");
+
+	if (armv7m->pre_restore_context)
+		armv7m->pre_restore_context(target);
+		
+	for (i = ARMV7NUMCOREREGS; i >= 0; i--)
+	{
+		if (armv7m->core_cache->reg_list[i].dirty)
+		{
+			armv7m->write_core_reg(target, i);
+		}
+	}
+	
+	if (armv7m->post_restore_context)
+		armv7m->post_restore_context(target);
+		
+	return ERROR_OK;		
+}
+
+
 /* Core state functions */
 char enamebuf[32];
 char *armv7m_exception_string(int number)
@@ -207,7 +234,6 @@ int armv7m_set_core_reg(reg_t *reg, u8 *buf)
 {
 	armv7m_core_reg_t *armv7m_reg = reg->arch_info;
 	target_t *target = armv7m_reg->target;
-	armv7m_common_t *armv7m_target = target->arch_info;
 	u32 value = buf_get_u32(buf, 0, 32);
 		
 	if (target->state != TARGET_HALTED)
@@ -310,12 +336,8 @@ int armv7m_get_gdb_reg_list(target_t *target, reg_t **reg_list[], int *reg_list_
 			(*reg_list)[i] = &armv7m_gdb_dummy_fp_reg;
 	}
 	/* ARMV7M is always in thumb mode, try to make GDB understand this if it does not support this arch */
-	//armv7m->core_cache->reg_list[15].value[0] |= 1;	
 	armv7m->process_context->reg_list[15].value[0] |= 1;	
-	//armv7m->core_cache->reg_list[ARMV7M_xPSR].value[0] = (1<<5);
-	//armv7m->process_context->reg_list[ARMV7M_xPSR].value[0] = (1<<5);
 	(*reg_list)[25] = &armv7m->process_context->reg_list[ARMV7M_xPSR];	
-	//(*reg_list)[25] = &armv7m->process_context->reg_list[ARMV7M_xPSR];	
 	return ERROR_OK;
 }
 
@@ -358,8 +380,6 @@ int armv7m_run_algorithm(struct target_s *target, int num_mem_params, mem_param_
 	for (i = 0; i < num_reg_params; i++)
 	{
 		reg_t *reg = register_get_by_name(armv7m->core_cache, reg_params[i].reg_name, 0);
-		//reg_t *reg = register_get_by_name(armv7m->debug_context, reg_params[i].reg_name, 0);
-		//armv7m_core_reg_t * armv7m_core_reg = reg->arch_info;
 		u32 regvalue;
 		
 		if (!reg)
@@ -375,7 +395,6 @@ int armv7m_run_algorithm(struct target_s *target, int num_mem_params, mem_param_
 		}
 		
 		regvalue = buf_get_u32(reg_params[i].value, 0, 32);
-		//armv7m->store_core_reg_u32(target, armv7m_core_reg->type, armv7m_core_reg->num, regvalue);
 		armv7m_set_core_reg(reg, reg_params[i].value);
 	}
 	
@@ -431,9 +450,7 @@ int armv7m_run_algorithm(struct target_s *target, int num_mem_params, mem_param_
 	{
 		if (reg_params[i].direction != PARAM_OUT)
 		{
-			//reg_t *reg = register_get_by_name(armv7m->core_cache, reg_params[i].reg_name, 0);
 			reg_t *reg = register_get_by_name(armv7m->debug_context, reg_params[i].reg_name, 0);
-			u32 regvalue;
 		
 			if (!reg)
 			{
@@ -447,23 +464,10 @@ int armv7m_run_algorithm(struct target_s *target, int num_mem_params, mem_param_
 				exit(-1);
 			}
 			
-			armv7m_core_reg_t *armv7m_core_reg = reg->arch_info;
-			//armv7m->load_core_reg_u32(target, armv7m_core_reg->type, armv7m_core_reg->num, &regvalue);
-			//buf_set_u32(reg_params[i].value, 0, 32, regvalue);
 			buf_set_u32(reg_params[i].value, 0, 32, buf_get_u32(reg->value, 0, 32));
 		}
 	}
 	
-	/* Mark all core registers !! except control !! as valid but dirty */
-	/* This will be done by armv7m_use_context in resume function */
-	//for (i = 0; i < armv7m->core_cache->num_regs-1; i++)
-	//{
-	//	armv7m->core_cache->reg_list[i].dirty = 1;
-	//}
-
-	// ????armv7m->core_state = core_state;
-	// ????armv7m->core_mode = core_mode;
-
 	return retval;
 }
 
@@ -488,7 +492,6 @@ reg_cache_t *armv7m_build_reg_cache(target_t *target)
 {
 	/* get pointers to arch-specific information */
 	armv7m_common_t *armv7m = target->arch_info;
-	arm_jtag_t *jtag_info = &armv7m->jtag_info;
 
 	int num_regs = ARMV7NUMCOREREGS;
 	reg_cache_t **cache_p = register_get_last_cache_p(&target->reg_cache);
@@ -549,7 +552,7 @@ reg_cache_t *armv7m_build_reg_cache(target_t *target)
 		reg_list[i].arch_info = &arch_info[i];
 	}
 	
-    return cache;
+	return cache;
 }
 
 int armv7m_init_target(struct command_context_s *cmd_ctx, struct target_s *target)
@@ -573,7 +576,5 @@ int armv7m_init_arch_info(target_t *target, armv7m_common_t *armv7m)
 
 int armv7m_register_commands(struct command_context_s *cmd_ctx)
 {
-	int retval;
-	
 	return ERROR_OK;
 }
diff --git a/src/target/armv7m.h b/src/target/armv7m.h
index 49043e1d..8d06cc65 100644
--- a/src/target/armv7m.h
+++ b/src/target/armv7m.h
@@ -166,6 +166,7 @@ extern int armv7m_invalidate_core_regs(target_t *target);
 extern enum armv7m_runcontext armv7m_get_context(target_t *target);
 extern int armv7m_use_context(target_t *target, enum armv7m_runcontext new_ctx);
 extern enum armv7m_runcontext armv7m_get_context(target_t *target);
+extern int armv7m_restore_context(target_t *target);
 
 /* Thumb mode instructions
  */
diff --git a/src/target/cortex_m3.c b/src/target/cortex_m3.c
index bdc8b717..c47fbbf8 100644
--- a/src/target/cortex_m3.c
+++ b/src/target/cortex_m3.c
@@ -23,8 +23,6 @@
 #include "config.h"
 #endif
 
-#define USE_SP_REGS
-
 #include "replacements.h"
 
 #include "cortex_m3.h"
@@ -157,6 +155,7 @@ int cortex_m3_cpsid(target_t *target, u32 IF)
 int cortex_m3_endreset_event(target_t *target)
 {
 	int i;
+	u32 dcb_demcr;
 	
 	/* get pointers to arch-specific information */
 	armv7m_common_t *armv7m = target->arch_info;
@@ -165,7 +164,9 @@ int cortex_m3_endreset_event(target_t *target)
 	cortex_m3_fp_comparator_t *fp_list = cortex_m3->fp_comparator_list; 
 	cortex_m3_dwt_comparator_t *dwt_list = cortex_m3->dwt_comparator_list;
 
-	DEBUG(" ");
+	ahbap_read_system_atomic_u32(swjdp, DCB_DEMCR, &dcb_demcr);
+	DEBUG("DCB_DEMCR = 0x%8.8x",dcb_demcr);
+	
 	/* Enable debug requests */
 	ahbap_read_system_atomic_u32(swjdp, DCB_DHCSR, &cortex_m3->dcb_dhcsr);
 	if (!(cortex_m3->dcb_dhcsr & C_DEBUGEN))
@@ -191,6 +192,7 @@ int cortex_m3_endreset_event(target_t *target)
 		target_write_u32(target, dwt_list[i].dwt_comparator_address | 0x4, dwt_list[i].mask);
 		target_write_u32(target, dwt_list[i].dwt_comparator_address | 0x8, dwt_list[i].function);
 	}
+	swjdp_transaction_endcheck(swjdp);
 	
 	/* Make sure working_areas are all free */
 	target_free_all_working_areas(target);
@@ -206,7 +208,6 @@ int cortex_m3_examine_debug_reason(target_t *target)
 	/* get pointers to arch-specific information */
 	armv7m_common_t *armv7m = target->arch_info;
 	cortex_m3_common_t *cortex_m3 = armv7m->arch_info;
-	swjdp_common_t *swjdp = &cortex_m3->swjdp_info;
 
 	/* THIS IS NOT GOOD, TODO - better logic for detection of debug state reason */
 	/* only check the debug reason if we don't know it already */
@@ -283,7 +284,7 @@ int cortex_m3_examine_exception_reason(target_t *target)
 
 int cortex_m3_debug_entry(target_t *target)
 {
-	int i, irq_is_pending;
+	int i;
 	u32 xPSR;
 	int retval;
 
@@ -321,13 +322,11 @@ int cortex_m3_debug_entry(target_t *target)
 
 
 	/* Now we can load SP core registers */	
-#ifdef USE_SP_REGS
 	for (i = ARMV7M_PRIMASK; i < ARMV7NUMCOREREGS; i++)
 	{
 		if (!armv7m->core_cache->reg_list[i].valid)
 			armv7m->read_core_reg(target, i);		
 	}
-#endif
 
 	/* Are we in an exception handler */
     armv7m->core_mode = (xPSR & 0x1FF) ? ARMV7M_MODE_HANDLER : ARMV7M_MODE_THREAD;
@@ -345,37 +344,6 @@ int cortex_m3_debug_entry(target_t *target)
 	return ERROR_OK;
 }
 
-int cortex_m3_restore_context(target_t *target)
-{
-	int i;
-	
-	/* get pointers to arch-specific information */
-	armv7m_common_t *armv7m = target->arch_info;
-	cortex_m3_common_t *cortex_m3 = armv7m->arch_info;
-
-	DEBUG(" ");
-
-	if (armv7m->pre_restore_context)
-		armv7m->pre_restore_context(target);
-		
-#ifdef USE_SP_REGS
-	for (i = ARMV7NUMCOREREGS; i >= 0; i--)
-#else
-	for (i = ARMV7M_PSP; i >= 0; i--)
-#endif
-	{
-		if (armv7m->core_cache->reg_list[i].dirty)
-		{
-			armv7m->write_core_reg(target, i);
-		}
-	}
-	
-	if (armv7m->post_restore_context)
-		armv7m->post_restore_context(target);
-		
-	return ERROR_OK;		
-}
-
 enum target_state cortex_m3_poll(target_t *target)
 {
 	int retval;
@@ -415,7 +383,7 @@ enum target_state cortex_m3_poll(target_t *target)
 		if ((prev_target_state == TARGET_RUNNING) || (prev_target_state == TARGET_RESET))
 		{
 			if ((retval = cortex_m3_debug_entry(target)) != ERROR_OK)
-				return retval;
+				return TARGET_UNKNOWN;
 			
 			target_call_event_callbacks(target, TARGET_EVENT_HALTED);
 		}
@@ -423,7 +391,7 @@ enum target_state cortex_m3_poll(target_t *target)
 		{
 			DEBUG(" ");
 			if ((retval = cortex_m3_debug_entry(target)) != ERROR_OK)
-				return retval;
+				return TARGET_UNKNOWN;
 
 			target_call_event_callbacks(target, TARGET_EVENT_DEBUG_HALTED);
 		}
@@ -449,6 +417,35 @@ int cortex_m3_halt(target_t *target)
 	
 	DEBUG("target->state: %s", target_state_strings[target->state]);
 	
+	if (target->state == TARGET_HALTED)
+	{
+		WARNING("target was already halted");
+		return ERROR_TARGET_ALREADY_HALTED;
+	}
+	
+	if (target->state == TARGET_UNKNOWN)
+	{
+		WARNING("target was in unknown state when halt was requested");
+	}
+	
+	if (target->state == TARGET_RESET) 
+	{
+		if ((jtag_reset_config & RESET_SRST_PULLS_TRST) && jtag_srst)
+		{
+			ERROR("can't request a halt while in reset if nSRST pulls nTRST");
+			return ERROR_TARGET_FAILURE;
+		}
+		else
+		{
+			/* we came here in a reset_halt or reset_init sequence
+			 * debug entry was already prepared in cortex_m3_prepare_reset_halt()
+			 */
+			target->debug_reason = DBG_REASON_DBGRQ;
+			
+			return ERROR_OK; 
+		}
+	}
+
 	/* Write to Debug Halting Control and Status Register */
 	ahbap_write_system_atomic_u32(swjdp, DCB_DHCSR, DBGKEY | C_DEBUGEN | C_HALT );
 
@@ -510,14 +507,19 @@ int cortex_m3_prepare_reset_halt(struct target_s *target)
 	armv7m_common_t *armv7m = target->arch_info;
 	cortex_m3_common_t *cortex_m3 = armv7m->arch_info;
 	swjdp_common_t *swjdp = &cortex_m3->swjdp_info;
-		
+	u32 dcb_demcr, dcb_dhcsr;
+	
 	/* Enable debug requests */
 	ahbap_read_system_atomic_u32(swjdp, DCB_DHCSR, &cortex_m3->dcb_dhcsr);
 	if (!(cortex_m3->dcb_dhcsr & C_DEBUGEN))
 		ahbap_write_system_u32(swjdp, DCB_DHCSR, DBGKEY | C_DEBUGEN );
 	
 	/* Enter debug state on reset, cf. end_reset_event() */
-	ahbap_write_system_u32(swjdp, DCB_DEMCR, TRCENA | VC_HARDERR | VC_BUSERR | VC_CORERESET );
+	ahbap_write_system_atomic_u32(swjdp, DCB_DEMCR, TRCENA | VC_HARDERR | VC_BUSERR | VC_CORERESET );
+	
+	ahbap_read_system_atomic_u32(swjdp, DCB_DHCSR, &dcb_dhcsr);
+	ahbap_read_system_atomic_u32(swjdp, DCB_DEMCR, &dcb_demcr);
+	DEBUG("dcb_dhcsr 0x%x, dcb_demcr 0x%x, ", dcb_dhcsr, dcb_demcr);
 	
 	return ERROR_OK;
 }
@@ -584,7 +586,7 @@ int cortex_m3_resume(struct target_s *target, int current, u32 address, int hand
 	
 	resume_pc = buf_get_u32(armv7m->core_cache->reg_list[15].value, 0, 32);
 
-	cortex_m3_restore_context(target);
+	armv7m_restore_context(target);
 	
 	/* the front-end may request us not to handle breakpoints */
 	if (handle_breakpoints)
@@ -658,7 +660,7 @@ int cortex_m3_step(struct target_s *target, int current, u32 address, int handle
 	
 	target->debug_reason = DBG_REASON_SINGLESTEP;
 	
-	cortex_m3_restore_context(target);
+	armv7m_restore_context(target);
 	
 	target_call_event_callbacks(target, TARGET_EVENT_RESUMED);
     
@@ -1269,7 +1271,7 @@ void cortex_m3_build_reg_cache(target_t *target)
 
 int cortex_m3_init_target(struct command_context_s *cmd_ctx, struct target_s *target)
 {
-	u32 did1, dc0, cpuid, fpcr, dwtcr, ictr;
+	u32 cpuid, fpcr, dwtcr, ictr;
 	int i;
 	
 	/* get pointers to arch-specific information */
@@ -1333,8 +1335,6 @@ int cortex_m3_init_arch_info(target_t *target, cortex_m3_common_t *cortex_m3, in
 	armv7m_common_t *armv7m;
 	armv7m = &cortex_m3->armv7m;
 
-	arm_jtag_t *jtag_info = &cortex_m3->jtag_info;	
-
 	/* prepare JTAG information for the new target */
 	cortex_m3->jtag_info.chain_pos = chain_pos;
 	cortex_m3->jtag_info.scann_size = 4;
diff --git a/src/target/cortex_swjdp.c b/src/target/cortex_swjdp.c
index 2a2267ff..85a2abc3 100644
--- a/src/target/cortex_swjdp.c
+++ b/src/target/cortex_swjdp.c
@@ -164,7 +164,7 @@ int scan_inout_check_u32(swjdp_common_t *swjdp, u8 instr, u8 reg_addr, u8 RnW, u
 		swjdp_scan_u32(swjdp->jtag_info, SWJDP_IR_DPACC, 0xC, DPAP_READ, 0, invalue, &swjdp->ack);
 	}
 	
-	/* In TRANS_MODE_ATOMIC all SWJDP_IR_APACC transactions wait for ack=OK/FAULT and the check CTRL_STAT */
+	/* In TRANS_MODE_ATOMIC all SWJDP_IR_APACC transactions wait for ack=OK/FAULT and then check CTRL_STAT */
 	if ((instr == SWJDP_IR_APACC) && (swjdp->trans_mode == TRANS_MODE_ATOMIC))
 	{
 		return swjdp_transaction_endcheck(swjdp);
@@ -179,6 +179,7 @@ int swjdp_transaction_endcheck(swjdp_common_t *swjdp)
 	u32 ctrlstat;
 
 	scan_inout_check_u32(swjdp, SWJDP_IR_DPACC, DP_CTRL_STAT, DPAP_READ, 0, &ctrlstat);
+	scan_inout_check_u32(swjdp, SWJDP_IR_DPACC, DP_CTRL_STAT, DPAP_READ, 0, &ctrlstat);
 	jtag_execute_queue();
 	
 	swjdp->ack = swjdp->ack & 0x7;
@@ -191,6 +192,7 @@ int swjdp_transaction_endcheck(swjdp_common_t *swjdp)
 			if (waitcount > 100)
 			{
 				WARNING("Timeout waiting for ACK = OK/FAULT in SWJDP transaction");
+
 				return ERROR_JTAG_DEVICE_ERROR;
 			}
 		}
@@ -199,6 +201,7 @@ int swjdp_transaction_endcheck(swjdp_common_t *swjdp)
 			WARNING("Invalid ACK in SWJDP transaction");
 			return ERROR_JTAG_DEVICE_ERROR;
 		}
+
 		scan_inout_check_u32(swjdp, SWJDP_IR_DPACC, DP_CTRL_STAT, DPAP_READ, 0, &ctrlstat);
 		jtag_execute_queue();
 		swjdp->ack = swjdp->ack & 0x7;
@@ -418,7 +421,7 @@ int ahbap_write_buf(swjdp_common_t *swjdp, u8 *buffer, int count, u32 address)
 	count = count - 4 * wcount;
 	while (wcount > 0)
 	{
-		/* Adjust to read within 4K block boundaries */
+		/* Adjust to write blocks within 4K aligned boundaries */
 		blocksize = (0x1000 - (0xFFF & address)) >> 2;
 		if (wcount < blocksize)
 			blocksize = wcount;
@@ -439,7 +442,7 @@ int ahbap_write_buf(swjdp_common_t *swjdp, u8 *buffer, int count, u32 address)
 		}
 		if (errorcount > 1)
 		{
-			WARNING("Block read error address 0x%x, count 0x%x", address, count);
+			WARNING("Block write error address 0x%x, wcount 0x%x", address, wcount);
 			return ERROR_JTAG_DEVICE_ERROR;
 		}
 	}
@@ -573,7 +576,7 @@ int ahbap_read_buf_u16(swjdp_common_t *swjdp, u8 *buffer, int count, u32 address
 int ahbap_block_read_u32(swjdp_common_t *swjdp, u32 *buffer, int count, u32 address)
 {
 	int readcount, errorcount = 0;
-	u32 blockmax, blocksize;
+	u32 blocksize;
 	
 	swjdp->trans_mode = TRANS_MODE_COMPOSITE;
 	
diff --git a/src/target/target.c b/src/target/target.c
index de71b140..71ad1e42 100644
--- a/src/target/target.c
+++ b/src/target/target.c
@@ -862,7 +862,7 @@ int target_register_user_commands(struct command_context_s *cmd_ctx)
 	register_command(cmd_ctx,  NULL, "wait_halt", handle_wait_halt_command, COMMAND_EXEC, "wait for target halt [time (s)]");
 	register_command(cmd_ctx,  NULL, "halt", handle_halt_command, COMMAND_EXEC, "halt target");
 	register_command(cmd_ctx,  NULL, "resume", handle_resume_command, COMMAND_EXEC, "resume target [addr]");
-	register_command(cmd_ctx,  NULL, "step", handle_step_command, COMMAND_EXEC, "step one instruction");
+	register_command(cmd_ctx,  NULL, "step", handle_step_command, COMMAND_EXEC, "step one instruction from current PC or [addr]");
 	register_command(cmd_ctx,  NULL, "reset", handle_reset_command, COMMAND_EXEC, "reset target [run|halt|init|run_and_halt|run_and_init]");
 	register_command(cmd_ctx,  NULL, "soft_reset_halt", handle_soft_reset_halt_command, COMMAND_EXEC, "halt the target and do a soft reset");