On 07/15/2016 08:49 PM, Scott Wood wrote:
On Fri, 2016-07-15 at 09:45 +0200, Hector Palacios wrote:
nand_do_write_ops() determines if it is writing a partial page with the formula: part_pagewr = (column || writelen < (mtd->writesize - 1))
When 'writelen' is exactly 1 byte less than the NAND page size the formula equates to zero, so the code doesn't process it as a partial write, although it should. As a consequence the function remains in the while(1) loop with 'writelen' becoming 0xffffffff and iterating until the watchdog timeout triggers.
To reproduce the issue on a NAND with 2K page (0x800): => nand erase.part <partition> => nand write $loadaddr <partition> 7ff
Signed-off-by: Hector Palacios hector.palacios@digi.com
drivers/mtd/nand/nand_base.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c index 689716753ae6..c8be74849e56 100644 --- a/drivers/mtd/nand/nand_base.c +++ b/drivers/mtd/nand/nand_base.c @@ -877,7 +877,7 @@ static int nand_wait(struct mtd_info *mtd, struct nand_chip *chip)
u32 timer = (CONFIG_SYS_HZ * timeo) / 1000; u32 time_start;
- time_start = get_timer(0); while (get_timer(time_start) < timer) { if (chip->dev_ready) {
This change is unrelated.
Ok. Removed.
@@ -2411,7 +2411,7 @@ static int nand_do_write_ops(struct mtd_info *mtd, loff_t to, int cached = writelen > bytes && page != blockmask; uint8_t *wbuf = buf; int use_bufpoi;
int part_pagewr = (column || writelen < (mtd->writesize -1));
int part_pagewr = (column || writelen < mtd->writesize);if (part_pagewr) use_bufpoi = 1;
Could you send a non-RFC patch? This also needs to get fixed in Linux.
Done. I will prepare a patch for Linux, but do you know how to reproduce it in Linux? 'nandwrite' checks that the file size is a multiple of the page size or else it will ask you to force padding, and 'dd' over the mtdblock device is also rounding up the write size to a page size multiple. Maybe that's the reason why it went undetected for so long.
-- Hector Palacios