Support AArch64 SIMD/FP registers read/write

This patch adds support in openOCD to read/write AArch64 SIMD/FP registers.
This patch depends on a previous patch which adds support to generation 
of target xml by openOCD with nested architecture defined types. AArch64 
SIMD/FP registers assumes various types and to support all types we 
implement them as architecture defined type aarch64v which in turn 
consists of various architecture defined types. This is compatible with 
AArch64-FPU target xml in GDB. Please refer to 
binutils-gdb/gdb/features/aarch64-fpu.xml

Change-Id: I7ffb0c21b3c2e08f13720b765408b30aab2a9808
Signed-off-by: Omair Javaid <omair.javaid@linaro.org>
Reviewed-on: http://openocd.zylin.com/4373
Tested-by: jenkins
Reviewed-by: Matthias Welwarsky <matthias@welwarsky.de>

1 files changed, 58 insertions, 22 deletions

diff --git a/src/target/armv8_dpm.c b/src/target/armv8_dpm.c
index c79b1a0..91b2f51 100644
--- a/src/target/armv8_dpm.c
+++ b/src/target/armv8_dpm.c
@@ -650,21 +650,37 @@ int armv8_dpm_modeswitch(struct arm_dpm *dpm, enum arm_mode mode)
 static int dpmv8_read_reg(struct arm_dpm *dpm, struct reg *r, unsigned regnum)
 {
 	struct armv8_common *armv8 = dpm->arm->arch_info;
-	uint64_t value_64;
-	int retval;
+	int retval = ERROR_FAIL;
+
+	if (r->size <= 64) {
+		uint64_t value_64;
+		retval = armv8->read_reg_u64(armv8, regnum, &value_64);
+
+		if (retval == ERROR_OK) {
+			r->valid = true;
+			r->dirty = false;
+			buf_set_u64(r->value, 0, r->size, value_64);
+			if (r->size == 64)
+				LOG_DEBUG("READ: %s, %16.8llx", r->name, (unsigned long long) value_64);
+			else
+				LOG_DEBUG("READ: %s, %8.8x", r->name, (unsigned int) value_64);
+		}
+	} else if (r->size <= 128) {
+		uint64_t lvalue = 0, hvalue = 0;
+		retval = armv8->read_reg_u128(armv8, regnum, &lvalue, &hvalue);
+
+		if (retval == ERROR_OK) {
+			r->valid = true;
+			r->dirty = false;
 
-	retval = armv8->read_reg_u64(armv8, regnum, &value_64);
+			buf_set_u64(r->value, 0, 64, lvalue);
+			buf_set_u64(r->value + 8, 0, r->size - 64, hvalue);
 
-	if (retval == ERROR_OK) {
-		r->valid = true;
-		r->dirty = false;
-		buf_set_u64(r->value, 0, r->size, value_64);
-		if (r->size == 64)
-			LOG_DEBUG("READ: %s, %16.8llx", r->name, (unsigned long long) value_64);
-		else
-			LOG_DEBUG("READ: %s, %8.8x", r->name, (unsigned int) value_64);
+			LOG_DEBUG("READ: %s, lvalue=%16.8llx", r->name, (unsigned long long) lvalue);
+			LOG_DEBUG("READ: %s, hvalue=%16.8llx", r->name, (unsigned long long) hvalue);
+		}
 	}
-	return ERROR_OK;
+	return retval;
 }
 
 /*
@@ -674,20 +690,36 @@ static int dpmv8_write_reg(struct arm_dpm *dpm, struct reg *r, unsigned regnum)
 {
 	struct armv8_common *armv8 = dpm->arm->arch_info;
 	int retval = ERROR_FAIL;
-	uint64_t value_64;
 
-	value_64 = buf_get_u64(r->value, 0, r->size);
+	if (r->size <= 64) {
+		uint64_t value_64;
+
+		value_64 = buf_get_u64(r->value, 0, r->size);
+		retval = armv8->write_reg_u64(armv8, regnum, value_64);
 
-	retval = armv8->write_reg_u64(armv8, regnum, value_64);
-	if (retval == ERROR_OK) {
-		r->dirty = false;
-		if (r->size == 64)
-			LOG_DEBUG("WRITE: %s, %16.8llx", r->name, (unsigned long long)value_64);
-		else
-			LOG_DEBUG("WRITE: %s, %8.8x", r->name, (unsigned int)value_64);
+		if (retval == ERROR_OK) {
+			r->dirty = false;
+			if (r->size == 64)
+				LOG_DEBUG("WRITE: %s, %16.8llx", r->name, (unsigned long long)value_64);
+			else
+				LOG_DEBUG("WRITE: %s, %8.8x", r->name, (unsigned int)value_64);
+		}
+	} else if (r->size <= 128) {
+		uint64_t lvalue, hvalue;
+
+		lvalue = buf_get_u64(r->value, 0, 64);
+		hvalue = buf_get_u64(r->value + 8, 0, r->size - 64);
+		retval = armv8->write_reg_u128(armv8, regnum, lvalue, hvalue);
+
+		if (retval == ERROR_OK) {
+			r->dirty = false;
+
+			LOG_DEBUG("WRITE: %s, lvalue=%16.8llx", r->name, (unsigned long long) lvalue);
+			LOG_DEBUG("WRITE: %s, hvalue=%16.8llx", r->name, (unsigned long long) hvalue);
+		}
 	}
 
-	return ERROR_OK;
+	return retval;
 }
 
 /**
@@ -745,6 +777,10 @@ int armv8_dpm_read_current_registers(struct arm_dpm *dpm)
 		if (r->valid)
 			continue;
 
+		/* Skip reading FP-SIMD registers */
+		if (r->number >= ARMV8_V0 && r->number <= ARMV8_FPCR)
+			continue;
+
 		/*
 		 * Only read registers that are available from the
 		 * current EL (or core mode).