target/riscv: cleanup `get_riscv_debug_reg_ctx()`

This commit makes the function safe to use throughout the lifetime of a
target.

Change-Id: I7a573e5d3b70daec2cf8f47a2aa1e30e39321549

2 files changed, 9 insertions, 5 deletions

diff --git a/src/target/riscv/riscv-013.c b/src/target/riscv/riscv-013.c
index 651342a..ad7b28e 100644
--- a/src/target/riscv/riscv-013.c
+++ b/src/target/riscv/riscv-013.c
@@ -280,13 +280,17 @@ static dm013_info_t *get_dm(struct target *target)
 	return dm;
 }
 
-static riscv_debug_reg_ctx_t get_riscv_debug_reg_ctx(struct target *target)
+static riscv_debug_reg_ctx_t get_riscv_debug_reg_ctx(const struct target *target)
 {
-	RISCV_INFO(r);
+	if (!target_was_examined(target)) {
+		const riscv_debug_reg_ctx_t default_context = {0};
+		return default_context;
+	}
+
 	RISCV013_INFO(info);
 	const riscv_debug_reg_ctx_t context = {
-		.XLEN = { .value = r->xlen, .is_set = true },
-		.DXLEN = { .value = r->xlen, .is_set = true },
+		.XLEN = { .value = riscv_xlen(target), .is_set = true },
+		.DXLEN = { .value = riscv_xlen(target), .is_set = true },
 		.abits = { .value = info->abits, .is_set = true },
 	};
 	return context;
diff --git a/src/target/target.h b/src/target/target.h
index 975561b..8b50dcc 100644
--- a/src/target/target.h
+++ b/src/target/target.h
@@ -438,7 +438,7 @@ const char *target_type_name(struct target *target);
 int target_examine_one(struct target *target);
 
 /** @returns @c true if target_set_examined() has been called. */
-static inline bool target_was_examined(struct target *target)
+static inline bool target_was_examined(const struct target *target)
 {
 	return target->examined;
 }