- added ARMV7_GDB_HACKS define to armv7m.h, enabling all gdb hacks to be enabled/disabled for testing

- added armv7m dummy cpsr register to stop gdb setting thumb bit

git-svn-id: svn://svn.berlios.de/openocd/trunk@623 b42882b7-edfa-0310-969c-e2dbd0fdcd60

src/target/armv7m.c

@@ -75,6 +75,15 @@ reg_t armv7m_gdb_dummy_fps_reg =
 	"GDB dummy floating-point status register", armv7m_gdb_dummy_fps_value, 0, 1, 32, NULL, 0, NULL, 0
 };
 
+#ifdef ARMV7_GDB_HACKS
+u8 armv7m_gdb_dummy_cpsr_value[] = {0, 0, 0, 0};
+
+reg_t armv7m_gdb_dummy_cpsr_reg =
+{
+	"GDB dummy cpsr register", armv7m_gdb_dummy_cpsr_value, 0, 1, 32, NULL, 0, NULL, 0
+};
+#endif
+
 armv7m_core_reg_t armv7m_core_reg_list_arch_info[] = 
 {
 	/*  CORE_GP are accesible using the core debug registers */
@@ -199,7 +208,7 @@ int armv7m_read_core_reg(struct target_s *target, int num)
 	buf_set_u32(armv7m->core_cache->reg_list[num].value, 0, 32, reg_value);
 	armv7m->core_cache->reg_list[num].valid = 1;
 	armv7m->core_cache->reg_list[num].dirty = 0;
-		
+	
 	return ERROR_OK;	
 }
 
@@ -266,11 +275,18 @@ int armv7m_get_gdb_reg_list(target_t *target, reg_t **reg_list[], int *reg_list_
 	}
 	
 	(*reg_list)[24] = &armv7m_gdb_dummy_fps_reg;
+
+#ifdef ARMV7_GDB_HACKS
+	/* use dummy cpsr reg otherwise gdb may try and set the thumb bit */
+	(*reg_list)[25] = &armv7m_gdb_dummy_cpsr_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;
+#else
 	(*reg_list)[25] = &armv7m->core_cache->reg_list[ARMV7M_xPSR];
+#endif
+
 	return ERROR_OK;
 }
 

src/target/armv7m.h

@@ -27,6 +27,11 @@
 #include "target.h"
 #include "arm_jtag.h"
 
+/* define for enabling armv7 gdb workarounds */
+#if 1
+#define ARMV7_GDB_HACKS
+#endif
+
 enum armv7m_mode
 {
 	ARMV7M_MODE_THREAD = 0,

src/target/cortex_m3.c

@@ -53,6 +53,11 @@ int cortex_m3_store_core_reg_u32(target_t *target, enum armv7m_regtype type, u32
 int cortex_m3_target_request_data(target_t *target, u32 size, u8 *buffer);
 int cortex_m3_examine(struct command_context_s *cmd_ctx, struct target_s *target);
 
+#ifdef ARMV7_GDB_HACKS
+extern u8 armv7m_gdb_dummy_cpsr_value[];
+extern reg_t armv7m_gdb_dummy_cpsr_reg;
+#endif
+
 target_type_t cortexm3_target =
 {
 	.name = "cortex_m3",
@@ -313,7 +318,15 @@ int cortex_m3_debug_entry(target_t *target)
 	}
 
 	xPSR = buf_get_u32(armv7m->core_cache->reg_list[ARMV7M_xPSR].value, 0, 32);
-	
+
+#ifdef ARMV7_GDB_HACKS
+	/* copy real xpsr reg for gdb, setting thumb bit */
+	buf_set_u32(armv7m_gdb_dummy_cpsr_value, 0, 32, xPSR);
+	buf_set_u32(armv7m_gdb_dummy_cpsr_value, 5, 1, 1);
+	armv7m_gdb_dummy_cpsr_reg.valid = armv7m->core_cache->reg_list[ARMV7M_xPSR].valid;
+	armv7m_gdb_dummy_cpsr_reg.dirty = armv7m->core_cache->reg_list[ARMV7M_xPSR].dirty;
+#endif
+
 	/* For IT instructions xPSR must be reloaded on resume and clear on debug exec */
 	if (xPSR & 0xf00)
 	{
@@ -835,12 +848,14 @@ int cortex_m3_add_breakpoint(struct target_s *target, breakpoint_t *breakpoint)
 	if (cortex_m3->auto_bp_type)
 	{
 		breakpoint->type = (breakpoint->address < 0x20000000) ? BKPT_HARD : BKPT_SOFT;
-        if (breakpoint->length != 2) {
-            // XXX Hack: Replace all breakpoints with length != 2 with
-            // a hardware breakpoint. 
-            breakpoint->type = BKPT_HARD;
-            breakpoint->length = 2;
-        }
+#ifdef ARMV7_GDB_HACKS
+		if (breakpoint->length != 2) {
+			/* XXX Hack: Replace all breakpoints with length != 2 with
+			 * a hardware breakpoint. */ 
+			breakpoint->type = BKPT_HARD;
+			breakpoint->length = 2;
+		}
+#endif
 	}
 
 	if ((breakpoint->type == BKPT_HARD) && (breakpoint->address >= 0x20000000))
@@ -1111,14 +1126,17 @@ int cortex_m3_store_core_reg_u32(struct target_s *target, enum armv7m_regtype ty
 	cortex_m3_common_t *cortex_m3 = armv7m->arch_info;
 	swjdp_common_t *swjdp = &cortex_m3->swjdp_info;
 
-    // If the LR register is being modified, make sure it will put us
-    // in "thumb" mode, or an INVSTATE exception will occur. This is a
-    // hack to deal with the fact that gdb will sometimes "forge"
-    // return addresses, and doesn't set the LSB correctly (i.e., when
-    // printing expressions containing function calls, it sets LR=0.)
-    if (num==14)
-        value |= 0x01;
-
+#ifdef ARMV7_GDB_HACKS
+	/* If the LR register is being modified, make sure it will put us
+	 * in "thumb" mode, or an INVSTATE exception will occur. This is a
+	 * hack to deal with the fact that gdb will sometimes "forge"
+	 * return addresses, and doesn't set the LSB correctly (i.e., when
+	 * printing expressions containing function calls, it sets LR=0.) */
+	
+	if (num == 14)
+		value |= 0x01;
+#endif
+	 
 	if ((type == ARMV7M_REGISTER_CORE_GP) && (num <= ARMV7M_PSP))
 	{
 		retval = ahbap_write_coreregister_u32(swjdp, value, num);