armv7a: rework automatic flush-on-write handling

The following changes are implemented:
- Clean&Invalidate the VA range to PoC *before* the write takes place
- Remove SMP handling since DCCIMVA instruction already maintains SMP
  coherence.
- Remove separate Invalidate step

Change-Id: I19fd3cc226d8ecf2937276fc63258b6a26e369a7
Signed-off-by: Matthias Welwarsky <matthias@welwarsky.de>
Reviewed-on: http://openocd.zylin.com/3027
Reviewed-by: Paul Fertser <fercerpav@gmail.com>
Tested-by: jenkins

3 files changed, 15 insertions, 35 deletions

diff --git a/src/target/armv7a_cache.c b/src/target/armv7a_cache.c
index 98474ecb..da617b81 100644
--- a/src/target/armv7a_cache.c
+++ b/src/target/armv7a_cache.c
@@ -207,8 +207,7 @@ int armv7a_l1_d_cache_clean_virt(struct target *target, uint32_t virt,
 	for (i = 0; i < size; i += linelen) {
 		uint32_t offs = virt + i;
 
-		/* FIXME: do we need DCCVAC or DCCVAU */
-		/* FIXME: in both cases it is not enough for i-cache */
+		/* DCCMVAC - Data Cache Clean by MVA to PoC */
 		retval = dpm->instr_write_data_r0(dpm,
 				ARMV4_5_MCR(15, 0, 0, 7, 10, 1), offs);
 		if (retval != ERROR_OK)
@@ -339,6 +338,14 @@ done:
 	return retval;
 }
 
+int armv7a_cache_flush_virt(struct target *target, uint32_t virt,
+				uint32_t size)
+{
+	armv7a_l1_d_cache_flush_virt(target, virt, size);
+	armv7a_l2x_cache_flush_virt(target, virt, size);
+
+	return ERROR_OK;
+}
 
 /*
  * We assume that target core was chosen correctly. It means if same data
@@ -354,41 +361,11 @@ int armv7a_cache_auto_flush_on_write(struct target *target, uint32_t virt,
 					uint32_t size)
 {
 	struct armv7a_common *armv7a = target_to_armv7a(target);
-	int retval = ERROR_OK;
 
 	if (!armv7a->armv7a_mmu.armv7a_cache.auto_cache_enabled)
 		return ERROR_OK;
 
-	armv7a_l1_d_cache_clean_virt(target, virt, size);
-	armv7a_l2x_cache_flush_virt(target, virt, size);
-
-	if (target->smp) {
-		struct target_list *head;
-		struct target *curr;
-		head = target->head;
-		while (head != (struct target_list *)NULL) {
-			curr = head->target;
-			if (curr->state == TARGET_HALTED) {
-				retval = armv7a_l1_i_cache_inval_all(curr);
-				if (retval != ERROR_OK)
-					return retval;
-				retval = armv7a_l1_d_cache_inval_virt(target,
-						virt, size);
-				if (retval != ERROR_OK)
-					return retval;
-			}
-			head = head->next;
-		}
-	} else {
-		retval = armv7a_l1_i_cache_inval_all(target);
-		if (retval != ERROR_OK)
-			return retval;
-		retval = armv7a_l1_d_cache_inval_virt(target, virt, size);
-		if (retval != ERROR_OK)
-			return retval;
-	}
-
-	return retval;
+	return armv7a_cache_flush_virt(target, virt, size);
 }
 
 COMMAND_HANDLER(arm7a_l1_cache_info_cmd)
diff --git a/src/target/armv7a_cache.h b/src/target/armv7a_cache.h
index 81995ac3..fbd158b4 100644
--- a/src/target/armv7a_cache.h
+++ b/src/target/armv7a_cache.h
@@ -29,7 +29,8 @@ int armv7a_l1_i_cache_inval_virt(struct target *target, uint32_t virt,
 int armv7a_cache_auto_flush_on_write(struct target *target, uint32_t virt,
 					uint32_t size);
 int armv7a_cache_auto_flush_all_data(struct target *target);
-
+int armv7a_cache_flush_virt(struct target *target, uint32_t virt,
+				uint32_t size);
 extern const struct command_registration arm7a_cache_command_handlers[];
 
 /* CLIDR cache types */
diff --git a/src/target/cortex_a.c b/src/target/cortex_a.c
index f9c92736..39e59ae7 100644
--- a/src/target/cortex_a.c
+++ b/src/target/cortex_a.c
@@ -2754,10 +2754,12 @@ static int cortex_a_write_memory(struct target *target, uint32_t address,
 		if (retval != ERROR_OK)
 			return retval;
 	}
-	retval = cortex_a_write_apb_ab_memory(target, address, size, count, buffer);
 
+	/* memory writes bypass the caches, must flush before writing */
 	armv7a_cache_auto_flush_on_write(target, address, size * count);
 
+	retval = cortex_a_write_apb_ab_memory(target, address, size, count, buffer);
+
 	return retval;
 }