cortexm : Fix watchpoint so it works for v8m arch

blackmagic-debug · Nov 30, 2024 · 377235a · 377235a
1 parent b0eb8d0
commit 377235a
Show file tree

Hide file tree

Showing 2 changed files with 37 additions and 6 deletions.
diff --git a/src/target/cortexm.c b/src/target/cortexm.c
@@ -1062,6 +1062,25 @@ static uint32_t cortexm_dwt_func(target_s *target, target_breakwatch_e type)
 	}
 }
 
+static uint32_t cortexm_dwt_func_v8m(target_s *target, target_breakwatch_e type, size_t len)
+{
+	uint32_t x = CORTEXM_DWT_FUNC_ACTION_DEBUG_EVENT_V8M;
+	switch (type) {
+	case TARGET_WATCH_WRITE:
+		x |= CORTEXM_DWT_FUNC_MATCH_WRITE_V8M;
+		break;
+	case TARGET_WATCH_READ:
+		x |= CORTEXM_DWT_FUNC_MATCH_READ_V8M;
+		break;
+	case TARGET_WATCH_ACCESS:
+		x |= CORTEXM_DWT_FUNC_MATCH_ACCESS_V8M;
+	default:
+		return -1;
+	}
+	x |= CORTEXM_DWT_FUNC_LEN_VALUE(len);
+	return x;
+}
+
 static int cortexm_breakwatch_set(target_s *target, breakwatch_s *breakwatch)
 {
 	cortexm_priv_s *priv = target->priv;
@@ -1103,11 +1122,15 @@ static int cortexm_breakwatch_set(target_s *target, breakwatch_s *breakwatch)
 			return -1;
 
 		priv->base.watchpoints_mask |= 1U << i;
-
-		target_mem32_write32(target, CORTEXM_DWT_COMP(i), val);
-		target_mem32_write32(target, CORTEXM_DWT_MASK(i), cortexm_dwt_mask(breakwatch->size));
-		target_mem32_write32(target, CORTEXM_DWT_FUNC(i), cortexm_dwt_func(target, breakwatch->type));
-
+		if ((target->target_options & CORTEXM_TOPT_FLAVOUR_V8M)) {
+			target_mem32_write32(target, CORTEXM_DWT_COMP(i), val);
+			target_mem32_write32(
+				target, CORTEXM_DWT_FUNC(i), cortexm_dwt_func_v8m(target, breakwatch->type, breakwatch->size));
+		} else {
+			target_mem32_write32(target, CORTEXM_DWT_COMP(i), val);
+			target_mem32_write32(target, CORTEXM_DWT_MASK(i), cortexm_dwt_mask(breakwatch->size));
+			target_mem32_write32(target, CORTEXM_DWT_FUNC(i), cortexm_dwt_func(target, breakwatch->type));
+		}
 		breakwatch->reserved[0] = i;
 		return 0;
 	default:

diff --git a/src/target/cortexm.h b/src/target/cortexm.h
@@ -164,7 +164,15 @@ extern unsigned cortexm_wait_timeout;
 #define CORTEXM_DWT_FUNC_FUNC_READ      (5U << 0U)
 #define CORTEXM_DWT_FUNC_FUNC_WRITE     (6U << 0U)
 #define CORTEXM_DWT_FUNC_FUNC_ACCESS    (7U << 0U)
-
+/* Variant for V8M */
+#define CORTEXM_DWT_FUNC_MATCH_READ_V8M         (6U << 0U)
+#define CORTEXM_DWT_FUNC_MATCH_WRITE_V8M        (5U << 0U)
+#define CORTEXM_DWT_FUNC_MATCH_ACCESS_V8M       (4U << 0U)
+#define CORTEXM_DWT_FUNC_ACTION_TRIGGER_V8M     (0U << 4U)
+#define CORTEXM_DWT_FUNC_ACTION_DEBUG_EVENT_V8M (1U << 4U)
+#define CORTEXM_DWT_FUNC_LEN_VALUE(len)         (((len) >> 1) << 10U)
+
+/* */
 #define CORTEXM_XPSR_THUMB          (1U << 24U)
 #define CORTEXM_XPSR_EXCEPTION_MASK 0x0000001fU