Hi Gerlando,
On Tue, Apr 3, 2012 at 8:14 AM, Gerlando Falauto gerlando.falauto@keymile.com wrote:
Since "sf update" erases the last block as a whole, but only rewrites the meaningful initial part of it, the rest would be left erased, potentially erasing meaningful information. So, as a safety measure, have it rewrite the original content.
Signed-off-by: Gerlando Falauto gerlando.falauto@keymile.com Cc: Valentin Longchamp valentin.longchamp@keymile.com Cc: Holger Brunck holger.brunck@keymile.com
Acked-by: Simon Glass sjg@chromium.org
common/cmd_sf.c | 15 ++++++++++++++- 1 files changed, 14 insertions(+), 1 deletions(-)
diff --git a/common/cmd_sf.c b/common/cmd_sf.c index d97d4a5..0666f52 100644 --- a/common/cmd_sf.c +++ b/common/cmd_sf.c @@ -134,8 +134,10 @@ static const char *spi_flash_update_block(struct spi_flash *flash, u32 offset, { debug("offset=%#x, sector_size=%#x, len=%#zx\n", offset, flash->sector_size, len);
- if (spi_flash_read(flash, offset, len, cmp_buf))
- /* Read the entire sector so to allow for rewriting */
- if (spi_flash_read(flash, offset, flash->sector_size, cmp_buf))
return "read";
- /* Compare only what is meningful (len) */
if (memcmp(cmp_buf, buf, len) == 0) { debug("Skip region %x size %zx: no change\n", offset, len); @@ -145,6 +147,17 @@ static const char *spi_flash_update_block(struct spi_flash *flash, u32 offset, /* Erase the entire sector */ if (spi_flash_erase(flash, offset, flash->sector_size)) return "erase";
- /* If it's a partial sector, preserve the existing part */
- if (len != flash->sector_size) {
- /* Overwrite the first part of the sector with input data */
- memcpy(cmp_buf, buf, len);
- /* Rewrite the whole sector with original data at the end */
- if (spi_flash_write(flash, offset, flash->sector_size,
- cmp_buf))
- return "write";
- return NULL;
If you wrote just the last part of the sector here then you could perhaps avoid the memcpy() and the return NULL.
- }
- /* Rewrite the whole block from the source */
if (spi_flash_write(flash, offset, len, buf)) return "write"; return NULL; -- 1.7.1
Regards, Simon