riscv: Add have_progbuf_size check in vtype,vl writes and crs,fpr read-write

Added a check for have_progbuf_size before attempting to execute. This prevents program buffer access on targets
that do not support it, improving robustness and avoiding potential
execution failures when the program buffer is not available or too small.

Signed-off-by: Biancaa Ramesh <[email protected]>

Author: Biancaa Ramesh

src/target/riscv/riscv-013.c

@@ -1386,8 +1386,7 @@ static int fpr_read_progbuf(struct target *target, uint64_t *value,
 	assert(target->state == TARGET_HALTED);
 	assert(number >= GDB_REGNO_FPR0 && number <= GDB_REGNO_FPR31);
 	if (!has_sufficient_progbuf(target, 2)) {
-		LOG_DEBUG("Skipping FPR read: insufficient progbuf (size=%d)",
-		          get_info(target)->progbufsize);
+		LOG_TARGET_DEBUG("Skipping FPR read: insufficient progbuf (size=%u)", get_info(target)->progbufsize);
 		return ERROR_FAIL;
 	}
 
@@ -1423,8 +1422,7 @@ static int csr_read_progbuf(struct target *target, uint64_t *value,
 	assert(target->state == TARGET_HALTED);
 	assert(number >= GDB_REGNO_CSR0 && number <= GDB_REGNO_CSR4095);
 	if (!has_sufficient_progbuf(target, 2)) {
-		LOG_DEBUG("Skipping CSR read: insufficient progbuf (size=%d)",
-		          get_info(target)->progbufsize);
+		LOG_TARGET_DEBUG("Skipping CSR read: insufficient progbuf (size=%u)", get_info(target)->progbufsize);
 		return ERROR_FAIL;
 	}
 
@@ -1441,6 +1439,7 @@ static int csr_read_progbuf(struct target *target, uint64_t *value,
 	return register_read_abstract(target, value, GDB_REGNO_S0) != ERROR_OK;
 }
 
+
 /**
  * This function reads a register by writing a program to program buffer and
  * executing it.
@@ -1495,8 +1494,7 @@ static int fpr_write_progbuf(struct target *target, enum gdb_regno number,
 	assert(target->state == TARGET_HALTED);
 	assert(number >= GDB_REGNO_FPR0 && number <= GDB_REGNO_FPR31);
 	if (!has_sufficient_progbuf(target, 2)) {
-		LOG_DEBUG("Skipping FPR Write: insufficient progbuf (size=%d)",
-		          get_info(target)->progbufsize);
+		LOG_TARGET_DEBUG("Skipping FPR Write: insufficient progbuf (size=%u)",get_info(target)->progbufsize);
 		return ERROR_FAIL;
 	}
 	const unsigned int freg = number - GDB_REGNO_FPR0;
@@ -1530,6 +1528,11 @@ static int fpr_write_progbuf(struct target *target, enum gdb_regno number,
 static int vtype_write_progbuf(struct target *target, riscv_reg_t value)
 {
 	assert(target->state == TARGET_HALTED);
+	/* Ensure program buffer is large enough for 2 instructions */
+	if (!has_sufficient_progbuf(target, 2)) {
+		LOG_TARGET_DEBUG("Skipping vtype write: insufficient progbuf (size=%u)", get_info(target)->progbufsize);
+		return ERROR_FAIL;
+	}
 
 	if (riscv013_reg_save(target, GDB_REGNO_S0) != ERROR_OK)
 		return ERROR_FAIL;
@@ -1551,6 +1554,11 @@ static int vtype_write_progbuf(struct target *target, riscv_reg_t value)
 static int vl_write_progbuf(struct target *target, riscv_reg_t value)
 {
 	assert(target->state == TARGET_HALTED);
+	/* Ensure program buffer is large enough for 2 instructions */
+	if (!has_sufficient_progbuf(target, 2)) {
+		LOG_TARGET_DEBUG("Skipping vl write: insufficient progbuf (size=%u)", get_info(target)->progbufsize);
+		return ERROR_FAIL;
+	}
 
 	if (riscv013_reg_save(target, GDB_REGNO_S0) != ERROR_OK)
 		return ERROR_FAIL;
@@ -1575,8 +1583,7 @@ static int csr_write_progbuf(struct target *target, enum gdb_regno number,
 	assert(target->state == TARGET_HALTED);
 	assert(number >= GDB_REGNO_CSR0 && number <= GDB_REGNO_CSR4095);
 	if (!has_sufficient_progbuf(target, 2)) {
-		LOG_DEBUG("Skipping CSR write: insufficient progbuf (size=%d)",
-		          get_info(target)->progbufsize);
+		LOG_TARGET_DEBUG("Skipping CSR write: insufficient progbuf (size=%u)", get_info(target)->progbufsize);
 		return ERROR_FAIL;
 	}
 
@@ -5574,4 +5581,4 @@ static int riscv013_clear_abstract_error(struct target *target)
 	if (dm_write(target, DM_ABSTRACTCS, DM_ABSTRACTCS_CMDERR) != ERROR_OK)
 		result = ERROR_FAIL;
 	return result;
-}
+}