flash/nor/stm32lx: fixed writes at high adapter speeds

The busy flag must be polled after each half-page write.
At low clock speeds, no issue is observed when the poll
is omitted, because the writes complete before the next
write begins. But at high clock speeds the subsequent
writes would overlap and cause the operation to fail.

The status polls are done on the target for efficiency,
since the half-pages are very small.

Change-Id: Ia1e9b4a6a71930549b3d84a902744ce6e596301b
Signed-off-by: Jimmy <nhminus@gmail.com>
Reviewed-on: https://review.openocd.org/c/openocd/+/5598
Tested-by: jenkins
Reviewed-by: Jelle De Vleeschouwer
Reviewed-by: Tomas Vanek <vanekt@fbl.cz>
Reviewed-by: Andrzej Sierżęga <asier70@gmail.com>

1 files changed, 21 insertions, 4 deletions

diff --git a/src/flash/nor/stm32lx.c b/src/flash/nor/stm32lx.c
index 488dc97..1221196 100644
--- a/src/flash/nor/stm32lx.c
+++ b/src/flash/nor/stm32lx.c
@@ -425,12 +425,12 @@ static int stm32lx_write_half_pages(struct flash_bank *bank, const uint8_t *buff
 	struct stm32lx_flash_bank *stm32lx_info = bank->driver_priv;
 
 	uint32_t hp_nb = stm32lx_info->part_info.page_size / 2;
-	uint32_t buffer_size = 16384;
+	uint32_t buffer_size = (16384 / hp_nb) * hp_nb; /* must be multiple of hp_nb */
 	struct working_area *write_algorithm;
 	struct working_area *source;
 	uint32_t address = bank->base + offset;
 
-	struct reg_param reg_params[3];
+	struct reg_param reg_params[5];
 	struct armv7m_algorithm armv7m_info;
 
 	int retval = ERROR_OK;
@@ -440,6 +440,10 @@ static int stm32lx_write_half_pages(struct flash_bank *bank, const uint8_t *buff
 	};
 
 	/* Make sure we're performing a half-page aligned write. */
+	if (offset % hp_nb) {
+		LOG_ERROR("The offset must be %" PRIu32 "B-aligned but it is %" PRIi32 "B)", hp_nb, offset);
+		return ERROR_FAIL;
+	}
 	if (count % hp_nb) {
 		LOG_ERROR("The byte count must be %" PRIu32 "B-aligned but count is %" PRIu32 "B)", hp_nb, count);
 		return ERROR_FAIL;
@@ -476,6 +480,9 @@ static int stm32lx_write_half_pages(struct flash_bank *bank, const uint8_t *buff
 
 			LOG_WARNING("no large enough working area available, can't do block memory writes");
 			return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
+		} else {
+			/* Make sure we're still asking for an integral number of half-pages */
+			buffer_size -= buffer_size % hp_nb;
 		}
 	}
 
@@ -484,6 +491,8 @@ static int stm32lx_write_half_pages(struct flash_bank *bank, const uint8_t *buff
 	init_reg_param(&reg_params[0], "r0", 32, PARAM_OUT);
 	init_reg_param(&reg_params[1], "r1", 32, PARAM_OUT);
 	init_reg_param(&reg_params[2], "r2", 32, PARAM_OUT);
+	init_reg_param(&reg_params[3], "r3", 32, PARAM_OUT);
+	init_reg_param(&reg_params[4], "r4", 32, PARAM_OUT);
 
 	/* Enable half-page write */
 	retval = stm32lx_enable_write_half_page(bank);
@@ -494,6 +503,8 @@ static int stm32lx_write_half_pages(struct flash_bank *bank, const uint8_t *buff
 		destroy_reg_param(&reg_params[0]);
 		destroy_reg_param(&reg_params[1]);
 		destroy_reg_param(&reg_params[2]);
+		destroy_reg_param(&reg_params[3]);
+		destroy_reg_param(&reg_params[4]);
 		return retval;
 	}
 
@@ -524,8 +535,12 @@ static int stm32lx_write_half_pages(struct flash_bank *bank, const uint8_t *buff
 		buf_set_u32(reg_params[0].value, 0, 32, address);
 		/* The source address of the copy (R1) */
 		buf_set_u32(reg_params[1].value, 0, 32, source->address);
-		/* The length of the copy (R2) */
-		buf_set_u32(reg_params[2].value, 0, 32, this_count / 4);
+		/* The number of half pages to copy (R2) */
+		buf_set_u32(reg_params[2].value, 0, 32, this_count / hp_nb);
+		/* The size in byes of a half page (R3) */
+		buf_set_u32(reg_params[3].value, 0, 32, hp_nb);
+		/* The flash base address (R4) */
+		buf_set_u32(reg_params[4].value, 0, 32, stm32lx_info->flash_base);
 
 		/* 5: Execute the bunch of code */
 		retval = target_run_algorithm(target, 0, NULL,
@@ -593,6 +608,8 @@ static int stm32lx_write_half_pages(struct flash_bank *bank, const uint8_t *buff
 	destroy_reg_param(&reg_params[0]);
 	destroy_reg_param(&reg_params[1]);
 	destroy_reg_param(&reg_params[2]);
+	destroy_reg_param(&reg_params[3]);
+	destroy_reg_param(&reg_params[4]);
 
 	return retval;
 }