esp32: Fixes scracth register corruption

Fixes for the following bugs are incuded:
 - Scratch register A3 was corrupted when special, user or floating point
   dirty registers are written back to the processors.
 - esp32 dual core target was fetching user registers from PRO CPU instead of APP one

Closes #27

Author: gerekon

src/target/esp108.c

@@ -263,14 +263,16 @@ int esp108_write_dirty_registers(struct target *target)
 	uint32_t regval, windowbase;
 	struct esp108_common *esp108=(struct esp108_common*)target->arch_info;
 	struct reg *reg_list=esp108->core_cache->reg_list;
+	bool scratch_reg_dirty = false;
 
 	LOG_DEBUG("%s: %s", target->cmd_name, __FUNCTION__);
 
 	//We need to write the dirty registers in the cache list back to the processor.
 	//Start by writing the SFR/user registers.
 	for (i=0; i<XT_NUM_REGS; i++) {
 		if (reg_list[i].dirty) {
-			if (esp108_regs[i].type==XT_REG_SPECIAL || esp108_regs[i].type==XT_REG_USER) {
+			if (esp108_regs[i].type==XT_REG_SPECIAL || esp108_regs[i].type==XT_REG_USER || esp108_regs[i].type==XT_REG_FR) {
+				scratch_reg_dirty = true;
 				regval=esp108_reg_get(&reg_list[i]);
 				LOG_DEBUG("%s: Writing back reg %s val %08X", target->cmd_name, esp108_regs[i].name, regval);
 				esp108_queue_nexus_reg_write(target, NARADR_DDR, regval);
@@ -286,6 +288,9 @@ int esp108_write_dirty_registers(struct target *target)
 			}
 		}
 	}
+	if (scratch_reg_dirty) {
+		esp108_mark_register_dirty(target, XT_REG_IDX_A3);
+	}
 
 	//Grab the windowbase, we need it.
 	windowbase=esp108_reg_get(&reg_list[XT_REG_IDX_WINDOWBASE]);

src/target/esp32.c

@@ -171,7 +171,7 @@ static int esp32_fetch_all_regs(struct target *target)
 		for (i = 0; i < XT_NUM_REGS; i++) {
 			if (regReadable(esp32_regs[i].flags, cpenable) && (esp32_regs[i].type == XT_REG_SPECIAL || esp32_regs[i].type == XT_REG_USER)) {
 				if (esp32_regs[i].type == XT_REG_USER) {
-					esp108_queue_exec_ins(target, XT_INS_RUR(esp32_regs[i].reg_num, XT_REG_A3));
+					esp108_queue_exec_ins(esp32->esp32_targets[c], XT_INS_RUR(esp32_regs[i].reg_num, XT_REG_A3));
 				}
 				else if (esp32_regs[i].type == XT_REG_FR) {
 					esp108_queue_exec_ins(esp32->esp32_targets[c], XT_INS_RFR(esp32_regs[i].reg_num, XT_REG_A3));
@@ -242,14 +242,16 @@ static int esp32_write_dirty_registers(struct target *target, struct reg *reg_li
 	int i, j;
 	int res;
 	uint32_t regval, windowbase;
+	bool scratch_reg_dirty = false;
 
 	LOG_DEBUG("%s: %s", target->cmd_name, __FUNCTION__);
 
 	//We need to write the dirty registers in the cache list back to the processor.
 	//Start by writing the SFR/user registers.
 	for (i=0; i<XT_NUM_REGS; i++) {
 		if (reg_list[i].dirty) {
-			if (esp32_regs[i].type==XT_REG_SPECIAL || esp32_regs[i].type==XT_REG_USER) {
+			if (esp32_regs[i].type==XT_REG_SPECIAL || esp32_regs[i].type==XT_REG_USER || esp32_regs[i].type==XT_REG_FR) {
+				scratch_reg_dirty = true;
 				regval=esp108_reg_get(&reg_list[i]);
 				LOG_DEBUG("%s: Writing back reg %s val %08X", target->cmd_name, esp32_regs[i].name, regval);
 				esp108_queue_nexus_reg_write(target, NARADR_DDR, regval);
@@ -265,6 +267,9 @@ static int esp32_write_dirty_registers(struct target *target, struct reg *reg_li
 			}
 		}
 	}
+	if (scratch_reg_dirty) {
+		esp32_mark_register_dirty(reg_list, XT_REG_IDX_A3);
+	}
 
 	//Grab the windowbase, we need it.
 	windowbase=esp108_reg_get(&reg_list[XT_REG_IDX_WINDOWBASE]);