flash/nor/stm32f1x: adjust size of the flash loader buffer

target_run_flash_async_algorithm expects the source_buffer to have
at least 2 words reserved for read and write pointers in addition to the
FIFO buffer. If the size of the data to be flashed is <= 8 bytes then
the flash function will fail with "corrupted fifo read pointer" error.

Ensure the allocated buffer is big enough to hold both FIFO buffer and
read/write pointers.

Change-Id: I09c22eaac517b8cfea8e0b463f5deb6b98afd267
Signed-off-by: Simon Smiganovski <simon.smiganovski@fruitcore.de>
Signed-off-by: Paul Fertser <fercerpav@gmail.com>
Reviewed-on: https://review.openocd.org/c/openocd/+/7342
Tested-by: jenkins
Reviewed-by: Tomas Vanek <vanekt@fbl.cz>
Reviewed-by: Antonio Borneo <borneo.antonio@gmail.com>

diff --git a/src/flash/nor/stm32f1x.c b/src/flash/nor/stm32f1x.c
index e882d7f79575c557b54bef44f5f5bd0790ce2c1a..ab1ef2aefef0642d831a088a8c915f6ea9021f00 100644 (file)
--- a/src/flash/nor/stm32f1x.c
+++ b/src/flash/nor/stm32f1x.c
@@ -473,7 +473,7 @@ static int stm32x_write_block_async(struct flash_bank *bank, const uint8_t *buff
 
        /* memory buffer */
        buffer_size = target_get_working_area_avail(target);
-       buffer_size = MIN(hwords_count * 2, MAX(buffer_size, 256));
+       buffer_size = MIN(hwords_count * 2 + 8, MAX(buffer_size, 256));
        /* Normally we allocate all available working area.
         * MIN shrinks buffer_size if the size of the written block is smaller.
         * MAX prevents using async algo if the available working area is smaller