- explicitly disable monitor mode on ARM7/9 targets

- added "prepare_reset_halt()" to target_type_t, which allows reset_halt to be prepared before a reset is asserted, possibly preventing communication with the target
- arm7/9 devices now use a breakpoint at 0x0 or reset vector catching for debug out of reset


git-svn-id: svn://svn.berlios.de/openocd/trunk@141 b42882b7-edfa-0310-969c-e2dbd0fdcd60

12 files changed, 107 insertions, 18 deletions

diff --git a/src/target/arm720t.c b/src/target/arm720t.c
index 1b809e6d..7aff8a7e 100644
--- a/src/target/arm720t.c
+++ b/src/target/arm720t.c
@@ -63,6 +63,7 @@ target_type_t arm720t_target =
 	.assert_reset = arm7_9_assert_reset,
 	.deassert_reset = arm7_9_deassert_reset,
 	.soft_reset_halt = arm720t_soft_reset_halt,
+	.prepare_reset_halt = arm7_9_prepare_reset_halt,
 	
 	.get_gdb_reg_list = armv4_5_get_gdb_reg_list,
 
diff --git a/src/target/arm7_9_common.c b/src/target/arm7_9_common.c
index 7a409b0f..3a7c80a1 100644
--- a/src/target/arm7_9_common.c
+++ b/src/target/arm7_9_common.c
@@ -725,9 +725,8 @@ int arm7_9_deassert_reset(target_t *target)
 	
 	/* deassert reset lines */
 	jtag_add_reset(0, 0);
-		
+	
 	return ERROR_OK;
-
 }
 
 int arm7_9_clear_halt(target_t *target)
@@ -736,7 +735,8 @@ int arm7_9_clear_halt(target_t *target)
 	arm7_9_common_t *arm7_9 = armv4_5->arch_info;
 	reg_t *dbg_ctrl = &arm7_9->eice_cache->reg_list[EICE_DBG_CTRL];
 	
-	if (arm7_9->use_dbgrq)
+	/* we used DBGRQ only if we didn't come out of reset */
+	if (!arm7_9->debug_entry_from_reset && arm7_9->use_dbgrq)
 	{
 		/* program EmbeddedICE Debug Control Register to deassert DBGRQ
 		 */
@@ -745,18 +745,29 @@ int arm7_9_clear_halt(target_t *target)
 	}
 	else
 	{
-		/* restore registers if watchpoint unit 0 was in use
-		 */
-		if (arm7_9->wp0_used)
+		if (arm7_9->debug_entry_from_reset && arm7_9->has_vector_catch)
 		{
-			embeddedice_store_reg(&arm7_9->eice_cache->reg_list[EICE_W0_ADDR_MASK]);
-			embeddedice_store_reg(&arm7_9->eice_cache->reg_list[EICE_W0_DATA_MASK]);
-			embeddedice_store_reg(&arm7_9->eice_cache->reg_list[EICE_W0_CONTROL_MASK]);
+			/* if we came out of reset, and vector catch is supported, we used
+			 * vector catch to enter debug state
+			 * restore the register in that case
+			 */
+			embeddedice_store_reg(&arm7_9->eice_cache->reg_list[EICE_VEC_CATCH]);
+		}
+		else
+		{
+			/* restore registers if watchpoint unit 0 was in use
+			 */
+			if (arm7_9->wp0_used)
+			{
+				embeddedice_store_reg(&arm7_9->eice_cache->reg_list[EICE_W0_ADDR_MASK]);
+				embeddedice_store_reg(&arm7_9->eice_cache->reg_list[EICE_W0_DATA_MASK]);
+				embeddedice_store_reg(&arm7_9->eice_cache->reg_list[EICE_W0_CONTROL_MASK]);
+			}
+			/* control value always has to be restored, as it was either disabled, 
+			 * or enabled with possibly different bits
+			 */
+			embeddedice_store_reg(&arm7_9->eice_cache->reg_list[EICE_W0_CONTROL_VALUE]);
 		}
-		/* control value always has to be restored, as it was either disabled, 
-		 * or enabled with possibly different bits
-		 */
-		embeddedice_store_reg(&arm7_9->eice_cache->reg_list[EICE_W0_CONTROL_VALUE]);
 	}
 	
 	return ERROR_OK;
@@ -831,6 +842,28 @@ int arm7_9_soft_reset_halt(struct target_s *target)
 	return ERROR_OK;
 }
 
+int arm7_9_prepare_reset_halt(target_t *target)
+{
+	armv4_5_common_t *armv4_5 = target->arch_info;
+	arm7_9_common_t *arm7_9 = armv4_5->arch_info;
+	
+	if (arm7_9->has_vector_catch)
+	{
+		/* program vector catch register to catch reset vector */
+		embeddedice_write_reg(&arm7_9->eice_cache->reg_list[EICE_VEC_CATCH], 0x1);
+	}
+	else
+	{
+		/* program watchpoint unit to match on reset vector address */
+		embeddedice_write_reg(&arm7_9->eice_cache->reg_list[EICE_W0_ADDR_MASK], 0x3);
+		embeddedice_write_reg(&arm7_9->eice_cache->reg_list[EICE_W0_DATA_MASK], 0x0);
+		embeddedice_write_reg(&arm7_9->eice_cache->reg_list[EICE_W0_CONTROL_VALUE], 0x100);
+		embeddedice_write_reg(&arm7_9->eice_cache->reg_list[EICE_W0_CONTROL_MASK], 0xf7);
+	}
+	
+	return ERROR_OK;
+}
+
 int arm7_9_halt(target_t *target)
 {
 	armv4_5_common_t *armv4_5 = target->arch_info;
@@ -843,17 +876,29 @@ int arm7_9_halt(target_t *target)
 	{
 		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) && (jtag_reset_config & RESET_SRST_PULLS_TRST) && (jtag_srst))
+	if (target->state == TARGET_RESET) 
 	{
-		ERROR("can't request a halt while in reset if nSRST pulls nTRST");
-		return ERROR_TARGET_FAILURE;
+		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 arm7_9_prepare_reset_halt()
+			 */
+			target->debug_reason = DBG_REASON_DBGRQ;
+			
+			return ERROR_OK; 
+		}
 	}
 
 	if (arm7_9->use_dbgrq)
@@ -2477,6 +2522,8 @@ int arm7_9_init_arch_info(target_t *target, arm7_9_common_t *arm7_9)
 	
 	arm7_9->reinit_embeddedice = 0;
 	
+	arm7_9->debug_entry_from_reset = 0;
+	
 	arm7_9->dcc_working_area = NULL;
 	
 	arm7_9->fast_memory_access = 0;
diff --git a/src/target/arm7_9_common.h b/src/target/arm7_9_common.h
index fd9a9e1b..5e7d54a9 100644
--- a/src/target/arm7_9_common.h
+++ b/src/target/arm7_9_common.h
@@ -55,6 +55,7 @@ typedef struct arm7_9_common_s
 	int has_vector_catch;
 	
 	int reinit_embeddedice;
+	int debug_entry_from_reset;
 	
 	struct working_area_s *dcc_working_area;
 	
@@ -108,6 +109,7 @@ int arm7_9_deassert_reset(target_t *target);
 int arm7_9_reset_request_halt(target_t *target);
 int arm7_9_early_halt(target_t *target);
 int arm7_9_soft_reset_halt(struct target_s *target);
+int arm7_9_prepare_reset_halt(struct target_s *target);
 
 int arm7_9_halt(target_t *target);
 int arm7_9_debug_entry(target_t *target);
diff --git a/src/target/arm7tdmi.c b/src/target/arm7tdmi.c
index 3fcfa296..38917ded 100644
--- a/src/target/arm7tdmi.c
+++ b/src/target/arm7tdmi.c
@@ -66,6 +66,7 @@ target_type_t arm7tdmi_target =
 	.assert_reset = arm7_9_assert_reset,
 	.deassert_reset = arm7_9_deassert_reset,
 	.soft_reset_halt = arm7_9_soft_reset_halt,
+	.prepare_reset_halt = arm7_9_prepare_reset_halt,
 
 	.get_gdb_reg_list = armv4_5_get_gdb_reg_list,
 	
diff --git a/src/target/arm920t.c b/src/target/arm920t.c
index 1dae2319..d7fb8e11 100644
--- a/src/target/arm920t.c
+++ b/src/target/arm920t.c
@@ -70,6 +70,7 @@ target_type_t arm920t_target =
 	.assert_reset = arm7_9_assert_reset,
 	.deassert_reset = arm7_9_deassert_reset,
 	.soft_reset_halt = arm920t_soft_reset_halt,
+	.prepare_reset_halt = arm7_9_prepare_reset_halt,
 	
 	.get_gdb_reg_list = armv4_5_get_gdb_reg_list,
 
diff --git a/src/target/arm926ejs.c b/src/target/arm926ejs.c
index ecabfcd6..3931e898 100644
--- a/src/target/arm926ejs.c
+++ b/src/target/arm926ejs.c
@@ -70,6 +70,7 @@ target_type_t arm926ejs_target =
 	.assert_reset = arm7_9_assert_reset,
 	.deassert_reset = arm7_9_deassert_reset,
 	.soft_reset_halt = arm926ejs_soft_reset_halt,
+	.prepare_reset_halt = arm7_9_prepare_reset_halt,
 	
 	.get_gdb_reg_list = armv4_5_get_gdb_reg_list,
 
diff --git a/src/target/arm966e.c b/src/target/arm966e.c
index d4b6cf47..8b3414ca 100644
--- a/src/target/arm966e.c
+++ b/src/target/arm966e.c
@@ -63,6 +63,7 @@ target_type_t arm966e_target =
 	.assert_reset = arm966e_assert_reset,
 	.deassert_reset = arm966e_deassert_reset,
 	.soft_reset_halt = arm7_9_soft_reset_halt,
+	.prepare_reset_halt = arm7_9_prepare_reset_halt,
 
 	.get_gdb_reg_list = armv4_5_get_gdb_reg_list,
 
diff --git a/src/target/arm9tdmi.c b/src/target/arm9tdmi.c
index dd1ee79d..d21dff73 100644
--- a/src/target/arm9tdmi.c
+++ b/src/target/arm9tdmi.c
@@ -64,6 +64,7 @@ target_type_t arm9tdmi_target =
 	.assert_reset = arm7_9_assert_reset,
 	.deassert_reset = arm7_9_deassert_reset,
 	.soft_reset_halt = arm7_9_soft_reset_halt,
+	.prepare_reset_halt = arm7_9_prepare_reset_halt,
 
 	.get_gdb_reg_list = armv4_5_get_gdb_reg_list,
 
diff --git a/src/target/embeddedice.c b/src/target/embeddedice.c
index 699aa96f..76f87410 100644
--- a/src/target/embeddedice.c
+++ b/src/target/embeddedice.c
@@ -181,6 +181,15 @@ reg_cache_t* embeddedice_build_reg_cache(target_t *target, arm7_9_common_t *arm7
 			ERROR("unknown EmbeddedICE version (comms ctrl: 0x%8.8x)", buf_get_u32(reg_list[EICE_COMMS_CTRL].value, 0, 32));
 	}
 	
+	/* explicitly disable monitor mode */
+	if (arm7_9->has_monitor_mode)
+	{
+		embeddedice_read_reg(&reg_list[EICE_DBG_CTRL]);
+		jtag_execute_queue();
+		buf_set_u32(reg_list[EICE_DBG_CTRL].value, 4, 1, 0);
+		embeddedice_set_reg_w_exec(&reg_list[EICE_DBG_CTRL], reg_list[EICE_DBG_CTRL].value);
+	}
+	
 	return reg_cache;
 }
 
diff --git a/src/target/target.c b/src/target/target.c
index 548ea0c3..050a523e 100644
--- a/src/target/target.c
+++ b/src/target/target.c
@@ -247,7 +247,23 @@ int target_process_reset(struct command_context_s *cmd_ctx)
 {
 	int retval = ERROR_OK;
 	target_t *target;
-	 
+	
+	/* prepare reset_halt where necessary */
+	target = targets;
+	while (target)
+	{
+		switch (target->reset_mode)
+		{
+			case RESET_HALT:
+			case RESET_INIT:
+				target->type->prepare_reset_halt(target);
+				break;
+			default:
+				break;
+		}
+		target = target->next;
+	}
+	
 	target = targets;
 	while (target)
 	{
diff --git a/src/target/target.h b/src/target/target.h
index d340a778..9ab3d19a 100644
--- a/src/target/target.h
+++ b/src/target/target.h
@@ -110,6 +110,7 @@ typedef struct target_type_s
 	int (*assert_reset)(struct target_s *target);
 	int (*deassert_reset)(struct target_s *target);
 	int (*soft_reset_halt)(struct target_s *target);
+	int (*prepare_reset_halt)(struct target_s *target);
 	
 	/* target register access for gdb */
 	int (*get_gdb_reg_list)(struct target_s *target, struct reg_s **reg_list[], int *reg_list_size);
diff --git a/src/target/xscale.c b/src/target/xscale.c
index d6c9f215..9bb3ca75 100644
--- a/src/target/xscale.c
+++ b/src/target/xscale.c
@@ -58,6 +58,7 @@ int xscale_restore_context(target_t *target);
 int xscale_assert_reset(target_t *target);
 int xscale_deassert_reset(target_t *target);
 int xscale_soft_reset_halt(struct target_s *target);
+int xscale_prepare_reset_halt(struct target_s *target);
 
 int xscale_set_reg_u32(reg_t *reg, u32 value);
 
@@ -91,6 +92,7 @@ target_type_t xscale_target =
 	.assert_reset = xscale_assert_reset,
 	.deassert_reset = xscale_deassert_reset,
 	.soft_reset_halt = xscale_soft_reset_halt,
+	.prepare_reset_halt = xscale_prepare_reset_halt,
 
 	.get_gdb_reg_list = armv4_5_get_gdb_reg_list,
 	
@@ -1679,6 +1681,12 @@ int xscale_soft_reset_halt(struct target_s *target)
 	return ERROR_OK;
 }
 
+int xscale_prepare_reset_halt(struct target_s *target)
+{
+	/* nothing to be done for reset_halt on XScale targets */
+	return ERROR_OK;
+}
+
 int xscale_read_core_reg(struct target_s *target, int num, enum armv4_5_mode mode)
 {