Hi Miquel,
On 2/21/24 12:20, Miquel Raynal wrote:
Hi Christophe,
christophe.kerello@xxxxxxxxxxx wrote on Fri, 9 Feb 2024 14:35:44 +0100:
Hi Miquel,
I am testing last nand/next branch with the MP1 board, and i get an issue since this patch was applied.
When I read the SLC NAND using nandump tool (reading page 0 and page 1), the OOB is not displayed at expected. For page 1, oob is displayed when for page 0 the first data of the page are displayed.
The nanddump command used is: nanddump -c -o -l 0x2000 /dev/mtd9
I believe the issue is not in the indexes but related to the OOB. I
currently test on a device on which I would prefer not to smash the
content, so this is just compile tested and not run time verified, but
could you tell me if this solves the issue:
--- a/drivers/mtd/nand/raw/nand_base.c
+++ b/drivers/mtd/nand/raw/nand_base.c
@@ -3577,7 +3577,8 @@ static int nand_do_read_ops(struct nand_chip *chip, loff_t from,
oob = ops->oobbuf;
oob_required = oob ? 1 : 0;
- rawnand_enable_cont_reads(chip, page, readlen, col);
+ if (!oob_required)
+ rawnand_enable_cont_reads(chip, page, readlen, col);
I am still able to reproduce the problem with the patch applied.
In fact, when nanddump reads the OOB, nand_do_read_ops is not called,
but nand_read_oob_op is called, and as cont_read.ongoing=1, we are not
dumping the oob but the first data of the page.
page 0:
[ 57.642144] rawnand_enable_cont_reads: page=0, col=0, readlen=4096,
mtd->writesize=4096
[ 57.650210] rawnand_enable_cont_reads: end_page=1
[ 57.654858] nand_do_read_ops: cont_read.ongoing=1
[ 59.352562] nand_read_oob_op
page 1:
[ 59.355966] rawnand_enable_cont_reads: page=1, col=0, readlen=4096,
mtd->writesize=4096
[ 59.364045] rawnand_enable_cont_reads: end_page=1
[ 59.368757] nand_do_read_ops: cont_read.ongoing=0
[ 61.390098] nand_read_oob_op
I have not currently bandwidth to work on this topic and I need to
understand how continuous read is working, but I have made a patch and I
do not have issues with it when I am using nanddump or mtd_debug tools.
I have not tested it on a file system, so it is just a proposal.
--- a/drivers/mtd/nand/raw/nand_base.c
+++ b/drivers/mtd/nand/raw/nand_base.c
@@ -3466,22 +3466,18 @@ static void rawnand_enable_cont_reads(struct
nand_chip *chip, unsigned int page,
u32 readlen, int col)
{
struct mtd_info *mtd = nand_to_mtd(chip);
- unsigned int end_page, end_col;
+ unsigned int end_page;
chip->cont_read.ongoing = false;
- if (!chip->controller->supported_op.cont_read)
+ if (!chip->controller->supported_op.cont_read || col + readlen <=
mtd->writesize)
return;
- end_page = DIV_ROUND_UP(col + readlen, mtd->writesize);
- end_col = (col + readlen) % mtd->writesize;
+ end_page = page + DIV_ROUND_UP(col + readlen, mtd->writesize) - 1;
if (col)
page++;
- if (end_col && end_page)
- end_page--;
-
if (page + 1 > end_page)
return;
Tell me if this patch is breaking the continuous read feature or if it
can be pushed on the mailing list.
Regards,
Christophe Kerello.
while (1) {
struct mtd_ecc_stats ecc_stats = mtd->ecc_stats;
If that does not work, I'll destroy the content of the flash and
properly reproduce.
Thanks,
Miquèl
