* [PATCH] omap : nand : fix subpage ecc issue with prefetch
@ 2011-05-02 11:10 ` Kishore Kadiyala
0 siblings, 0 replies; 10+ messages in thread
From: Kishore Kadiyala @ 2011-05-02 11:10 UTC (permalink / raw)
To: linux-omap, linux-mtd, vimal.newwork, bdefaria; +Cc: Kishore Kadiyala
For prefetch engine, read and write got broken in commit '2c01946c'.
We never hit a scenario of not getting 'gpmc_prefetch_enable'
call success.
When reading/writing a subpage with a non divisible by 4 ecc number
of bytes, the mis-aligned bytes gets handled first before enabling
the Prefetch engine, then it reads/writes rest of the bytes.
Signed-off-by: Kishore Kadiyala <kishore.kadiyala@ti.com>
Signed-off-by: Vimal Singh <vimal.newwork@gmail.com>
Reported-by: Bryan DE FARIA <bdefaria@adeneo-embedded.com>
---
drivers/mtd/nand/omap2.c | 12 +++++-------
1 files changed, 5 insertions(+), 7 deletions(-)
diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c
index da9a351..2c8040f 100644
--- a/drivers/mtd/nand/omap2.c
+++ b/drivers/mtd/nand/omap2.c
@@ -263,11 +263,10 @@ static void omap_read_buf_pref(struct mtd_info *mtd, u_char *buf, int len)
if (ret) {
/* PFPW engine is busy, use cpu copy method */
if (info->nand.options & NAND_BUSWIDTH_16)
- omap_read_buf16(mtd, buf, len);
+ omap_read_buf16(mtd, (u_char *)p, len);
else
- omap_read_buf8(mtd, buf, len);
+ omap_read_buf8(mtd, (u_char *)p, len);
} else {
- p = (u32 *) buf;
do {
r_count = gpmc_read_status(GPMC_PREFETCH_FIFO_CNT);
r_count = r_count >> 2;
@@ -293,7 +292,7 @@ static void omap_write_buf_pref(struct mtd_info *mtd,
struct omap_nand_info, mtd);
uint32_t w_count = 0;
int i = 0, ret = 0;
- u16 *p;
+ u16 *p = (u16 *)buf;
unsigned long tim, limit;
/* take care of subpage writes */
@@ -309,11 +308,10 @@ static void omap_write_buf_pref(struct mtd_info *mtd,
if (ret) {
/* PFPW engine is busy, use cpu copy method */
if (info->nand.options & NAND_BUSWIDTH_16)
- omap_write_buf16(mtd, buf, len);
+ omap_write_buf16(mtd, (u_char *)p, len);
else
- omap_write_buf8(mtd, buf, len);
+ omap_write_buf8(mtd, (u_char *)p, len);
} else {
- p = (u16 *) buf;
while (len) {
w_count = gpmc_read_status(GPMC_PREFETCH_FIFO_CNT);
w_count = w_count >> 1;
--
1.7.4.1
^ permalink raw reply related [flat|nested] 10+ messages in thread
* [PATCH] omap : nand : fix subpage ecc issue with prefetch
@ 2011-05-02 11:10 ` Kishore Kadiyala
0 siblings, 0 replies; 10+ messages in thread
From: Kishore Kadiyala @ 2011-05-02 11:10 UTC (permalink / raw)
To: linux-omap, linux-mtd, vimal.newwork, bdefaria; +Cc: Kishore Kadiyala
For prefetch engine, read and write got broken in commit '2c01946c'.
We never hit a scenario of not getting 'gpmc_prefetch_enable'
call success.
When reading/writing a subpage with a non divisible by 4 ecc number
of bytes, the mis-aligned bytes gets handled first before enabling
the Prefetch engine, then it reads/writes rest of the bytes.
Signed-off-by: Kishore Kadiyala <kishore.kadiyala@ti.com>
Signed-off-by: Vimal Singh <vimal.newwork@gmail.com>
Reported-by: Bryan DE FARIA <bdefaria@adeneo-embedded.com>
---
drivers/mtd/nand/omap2.c | 12 +++++-------
1 files changed, 5 insertions(+), 7 deletions(-)
diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c
index da9a351..2c8040f 100644
--- a/drivers/mtd/nand/omap2.c
+++ b/drivers/mtd/nand/omap2.c
@@ -263,11 +263,10 @@ static void omap_read_buf_pref(struct mtd_info *mtd, u_char *buf, int len)
if (ret) {
/* PFPW engine is busy, use cpu copy method */
if (info->nand.options & NAND_BUSWIDTH_16)
- omap_read_buf16(mtd, buf, len);
+ omap_read_buf16(mtd, (u_char *)p, len);
else
- omap_read_buf8(mtd, buf, len);
+ omap_read_buf8(mtd, (u_char *)p, len);
} else {
- p = (u32 *) buf;
do {
r_count = gpmc_read_status(GPMC_PREFETCH_FIFO_CNT);
r_count = r_count >> 2;
@@ -293,7 +292,7 @@ static void omap_write_buf_pref(struct mtd_info *mtd,
struct omap_nand_info, mtd);
uint32_t w_count = 0;
int i = 0, ret = 0;
- u16 *p;
+ u16 *p = (u16 *)buf;
unsigned long tim, limit;
/* take care of subpage writes */
@@ -309,11 +308,10 @@ static void omap_write_buf_pref(struct mtd_info *mtd,
if (ret) {
/* PFPW engine is busy, use cpu copy method */
if (info->nand.options & NAND_BUSWIDTH_16)
- omap_write_buf16(mtd, buf, len);
+ omap_write_buf16(mtd, (u_char *)p, len);
else
- omap_write_buf8(mtd, buf, len);
+ omap_write_buf8(mtd, (u_char *)p, len);
} else {
- p = (u16 *) buf;
while (len) {
w_count = gpmc_read_status(GPMC_PREFETCH_FIFO_CNT);
w_count = w_count >> 1;
--
1.7.4.1
^ permalink raw reply related [flat|nested] 10+ messages in thread
* Re: [PATCH] omap : nand : fix subpage ecc issue with prefetch
2011-05-02 11:10 ` Kishore Kadiyala
@ 2011-05-05 14:20 ` Vimal Singh
-1 siblings, 0 replies; 10+ messages in thread
From: Vimal Singh @ 2011-05-05 14:20 UTC (permalink / raw)
To: Kishore Kadiyala; +Cc: linux-omap, linux-mtd, bdefaria
Hi Artem,
Can you please give a look on this patch?
This patch fixes is required for anyone who wants to use this driver
without using HW ECC.
-- Vimal
On Mon, May 2, 2011 at 4:40 PM, Kishore Kadiyala
<kishore.kadiyala@ti.com> wrote:
> For prefetch engine, read and write got broken in commit '2c01946c'.
> We never hit a scenario of not getting 'gpmc_prefetch_enable'
> call success.
> When reading/writing a subpage with a non divisible by 4 ecc number
> of bytes, the mis-aligned bytes gets handled first before enabling
> the Prefetch engine, then it reads/writes rest of the bytes.
>
> Signed-off-by: Kishore Kadiyala <kishore.kadiyala@ti.com>
> Signed-off-by: Vimal Singh <vimal.newwork@gmail.com>
> Reported-by: Bryan DE FARIA <bdefaria@adeneo-embedded.com>
> ---
> drivers/mtd/nand/omap2.c | 12 +++++-------
> 1 files changed, 5 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c
> index da9a351..2c8040f 100644
> --- a/drivers/mtd/nand/omap2.c
> +++ b/drivers/mtd/nand/omap2.c
> @@ -263,11 +263,10 @@ static void omap_read_buf_pref(struct mtd_info *mtd, u_char *buf, int len)
> if (ret) {
> /* PFPW engine is busy, use cpu copy method */
> if (info->nand.options & NAND_BUSWIDTH_16)
> - omap_read_buf16(mtd, buf, len);
> + omap_read_buf16(mtd, (u_char *)p, len);
> else
> - omap_read_buf8(mtd, buf, len);
> + omap_read_buf8(mtd, (u_char *)p, len);
> } else {
> - p = (u32 *) buf;
> do {
> r_count = gpmc_read_status(GPMC_PREFETCH_FIFO_CNT);
> r_count = r_count >> 2;
> @@ -293,7 +292,7 @@ static void omap_write_buf_pref(struct mtd_info *mtd,
> struct omap_nand_info, mtd);
> uint32_t w_count = 0;
> int i = 0, ret = 0;
> - u16 *p;
> + u16 *p = (u16 *)buf;
> unsigned long tim, limit;
>
> /* take care of subpage writes */
> @@ -309,11 +308,10 @@ static void omap_write_buf_pref(struct mtd_info *mtd,
> if (ret) {
> /* PFPW engine is busy, use cpu copy method */
> if (info->nand.options & NAND_BUSWIDTH_16)
> - omap_write_buf16(mtd, buf, len);
> + omap_write_buf16(mtd, (u_char *)p, len);
> else
> - omap_write_buf8(mtd, buf, len);
> + omap_write_buf8(mtd, (u_char *)p, len);
> } else {
> - p = (u16 *) buf;
> while (len) {
> w_count = gpmc_read_status(GPMC_PREFETCH_FIFO_CNT);
> w_count = w_count >> 1;
> --
> 1.7.4.1
>
>
--
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^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH] omap : nand : fix subpage ecc issue with prefetch
@ 2011-05-05 14:20 ` Vimal Singh
0 siblings, 0 replies; 10+ messages in thread
From: Vimal Singh @ 2011-05-05 14:20 UTC (permalink / raw)
To: Kishore Kadiyala; +Cc: bdefaria, linux-omap, linux-mtd
Hi Artem,
Can you please give a look on this patch?
This patch fixes is required for anyone who wants to use this driver
without using HW ECC.
-- Vimal
On Mon, May 2, 2011 at 4:40 PM, Kishore Kadiyala
<kishore.kadiyala@ti.com> wrote:
> For prefetch engine, read and write got broken in commit '2c01946c'.
> We never hit a scenario of not getting 'gpmc_prefetch_enable'
> call success.
> When reading/writing a subpage with a non divisible by 4 ecc number
> of bytes, the mis-aligned bytes gets handled first before enabling
> the Prefetch engine, then it reads/writes rest of the bytes.
>
> Signed-off-by: Kishore Kadiyala <kishore.kadiyala@ti.com>
> Signed-off-by: Vimal Singh <vimal.newwork@gmail.com>
> Reported-by: Bryan DE FARIA <bdefaria@adeneo-embedded.com>
> ---
> drivers/mtd/nand/omap2.c | 12 +++++-------
> 1 files changed, 5 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c
> index da9a351..2c8040f 100644
> --- a/drivers/mtd/nand/omap2.c
> +++ b/drivers/mtd/nand/omap2.c
> @@ -263,11 +263,10 @@ static void omap_read_buf_pref(struct mtd_info *mtd, u_char *buf, int len)
> if (ret) {
> /* PFPW engine is busy, use cpu copy method */
> if (info->nand.options & NAND_BUSWIDTH_16)
> - omap_read_buf16(mtd, buf, len);
> + omap_read_buf16(mtd, (u_char *)p, len);
> else
> - omap_read_buf8(mtd, buf, len);
> + omap_read_buf8(mtd, (u_char *)p, len);
> } else {
> - p = (u32 *) buf;
> do {
> r_count = gpmc_read_status(GPMC_PREFETCH_FIFO_CNT);
> r_count = r_count >> 2;
> @@ -293,7 +292,7 @@ static void omap_write_buf_pref(struct mtd_info *mtd,
> struct omap_nand_info, mtd);
> uint32_t w_count = 0;
> int i = 0, ret = 0;
> - u16 *p;
> + u16 *p = (u16 *)buf;
> unsigned long tim, limit;
>
> /* take care of subpage writes */
> @@ -309,11 +308,10 @@ static void omap_write_buf_pref(struct mtd_info *mtd,
> if (ret) {
> /* PFPW engine is busy, use cpu copy method */
> if (info->nand.options & NAND_BUSWIDTH_16)
> - omap_write_buf16(mtd, buf, len);
> + omap_write_buf16(mtd, (u_char *)p, len);
> else
> - omap_write_buf8(mtd, buf, len);
> + omap_write_buf8(mtd, (u_char *)p, len);
> } else {
> - p = (u16 *) buf;
> while (len) {
> w_count = gpmc_read_status(GPMC_PREFETCH_FIFO_CNT);
> w_count = w_count >> 1;
> --
> 1.7.4.1
>
>
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH] omap : nand : fix subpage ecc issue with prefetch
2011-05-02 11:10 ` Kishore Kadiyala
@ 2011-05-05 18:48 ` Artem Bityutskiy
-1 siblings, 0 replies; 10+ messages in thread
From: Artem Bityutskiy @ 2011-05-05 18:48 UTC (permalink / raw)
To: Kishore Kadiyala; +Cc: linux-omap, linux-mtd, vimal.newwork, bdefaria
On Mon, 2011-05-02 at 16:40 +0530, Kishore Kadiyala wrote:
> For prefetch engine, read and write got broken in commit '2c01946c'.
> We never hit a scenario of not getting 'gpmc_prefetch_enable'
> call success.
> When reading/writing a subpage with a non divisible by 4 ecc number
> of bytes, the mis-aligned bytes gets handled first before enabling
> the Prefetch engine, then it reads/writes rest of the bytes.
>
> Signed-off-by: Kishore Kadiyala <kishore.kadiyala@ti.com>
> Signed-off-by: Vimal Singh <vimal.newwork@gmail.com>
> Reported-by: Bryan DE FARIA <bdefaria@adeneo-embedded.com>
This needs a better commit message with more explanation and analysis of
the problem and how it was fixed.This commit message is not very
understandable. And then it needs also:
Cc: stable@kernel.org [2.6.36+]
Right? And then we could send it upstream.
--
Best Regards,
Artem Bityutskiy (Артём Битюцкий)
--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH] omap : nand : fix subpage ecc issue with prefetch
@ 2011-05-05 18:48 ` Artem Bityutskiy
0 siblings, 0 replies; 10+ messages in thread
From: Artem Bityutskiy @ 2011-05-05 18:48 UTC (permalink / raw)
To: Kishore Kadiyala; +Cc: bdefaria, vimal.newwork, linux-omap, linux-mtd
On Mon, 2011-05-02 at 16:40 +0530, Kishore Kadiyala wrote:
> For prefetch engine, read and write got broken in commit '2c01946c'.
> We never hit a scenario of not getting 'gpmc_prefetch_enable'
> call success.
> When reading/writing a subpage with a non divisible by 4 ecc number
> of bytes, the mis-aligned bytes gets handled first before enabling
> the Prefetch engine, then it reads/writes rest of the bytes.
>
> Signed-off-by: Kishore Kadiyala <kishore.kadiyala@ti.com>
> Signed-off-by: Vimal Singh <vimal.newwork@gmail.com>
> Reported-by: Bryan DE FARIA <bdefaria@adeneo-embedded.com>
This needs a better commit message with more explanation and analysis of
the problem and how it was fixed.This commit message is not very
understandable. And then it needs also:
Cc: stable@kernel.org [2.6.36+]
Right? And then we could send it upstream.
--
Best Regards,
Artem Bityutskiy (Артём Битюцкий)
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH] omap : nand : fix subpage ecc issue with prefetch
2011-05-05 18:48 ` Artem Bityutskiy
@ 2011-05-06 7:30 ` Vimal Singh
-1 siblings, 0 replies; 10+ messages in thread
From: Vimal Singh @ 2011-05-06 7:30 UTC (permalink / raw)
To: dedekind1; +Cc: Kishore Kadiyala, linux-omap, linux-mtd, bdefaria
On Fri, May 6, 2011 at 12:18 AM, Artem Bityutskiy <dedekind1@gmail.com> wrote:
> On Mon, 2011-05-02 at 16:40 +0530, Kishore Kadiyala wrote:
>> For prefetch engine, read and write got broken in commit '2c01946c'.
>> We never hit a scenario of not getting 'gpmc_prefetch_enable'
>> call success.
>> When reading/writing a subpage with a non divisible by 4 ecc number
>> of bytes, the mis-aligned bytes gets handled first before enabling
>> the Prefetch engine, then it reads/writes rest of the bytes.
>>
>> Signed-off-by: Kishore Kadiyala <kishore.kadiyala@ti.com>
>> Signed-off-by: Vimal Singh <vimal.newwork@gmail.com>
>> Reported-by: Bryan DE FARIA <bdefaria@adeneo-embedded.com>
>
> This needs a better commit message with more explanation and analysis of
> the problem and how it was fixed.This commit message is not very
> understandable. And then it needs also:
How about a commit log like this:
When reading/writing a subpage (When HW ECC is not available/enable)
for number of bytes not aligned to 4, the mis-aligned bytes gets
handled first (by cpu copy mathod) before enabling the Prefetch
engin to/from 'p' (start of buffer 'buf').
Then it reads/writes rest of the bytes with the help of Prefetch
engine, if available, or again by cpu copy mathod. Currnetly,
reading/writing of rest of bytes, is not done correctly. Its trying to
read/write again to/from begining of buffer 'buf', overwriting the
mis-aligned bytes.
For prefetch engine read and write it got broken in commit '2c01946c'.
And we never hit the scenario of not getting 'gpmc_prefetch_enable'
call sucess. So, problem did not get caught up.
This patch fixes the issue.
> Cc: stable@kernel.org [2.6.36+]
>
> Right? And then we could send it upstream.
Yes, sure. I think kishore can take care of adding this in 'cc'
while posting next time.
--
Regards,
Vimal Singh
--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
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^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH] omap : nand : fix subpage ecc issue with prefetch
@ 2011-05-06 7:30 ` Vimal Singh
0 siblings, 0 replies; 10+ messages in thread
From: Vimal Singh @ 2011-05-06 7:30 UTC (permalink / raw)
To: dedekind1; +Cc: bdefaria, linux-mtd, linux-omap, Kishore Kadiyala
On Fri, May 6, 2011 at 12:18 AM, Artem Bityutskiy <dedekind1@gmail.com> wrote:
> On Mon, 2011-05-02 at 16:40 +0530, Kishore Kadiyala wrote:
>> For prefetch engine, read and write got broken in commit '2c01946c'.
>> We never hit a scenario of not getting 'gpmc_prefetch_enable'
>> call success.
>> When reading/writing a subpage with a non divisible by 4 ecc number
>> of bytes, the mis-aligned bytes gets handled first before enabling
>> the Prefetch engine, then it reads/writes rest of the bytes.
>>
>> Signed-off-by: Kishore Kadiyala <kishore.kadiyala@ti.com>
>> Signed-off-by: Vimal Singh <vimal.newwork@gmail.com>
>> Reported-by: Bryan DE FARIA <bdefaria@adeneo-embedded.com>
>
> This needs a better commit message with more explanation and analysis of
> the problem and how it was fixed.This commit message is not very
> understandable. And then it needs also:
How about a commit log like this:
When reading/writing a subpage (When HW ECC is not available/enable)
for number of bytes not aligned to 4, the mis-aligned bytes gets
handled first (by cpu copy mathod) before enabling the Prefetch
engin to/from 'p' (start of buffer 'buf').
Then it reads/writes rest of the bytes with the help of Prefetch
engine, if available, or again by cpu copy mathod. Currnetly,
reading/writing of rest of bytes, is not done correctly. Its trying to
read/write again to/from begining of buffer 'buf', overwriting the
mis-aligned bytes.
For prefetch engine read and write it got broken in commit '2c01946c'.
And we never hit the scenario of not getting 'gpmc_prefetch_enable'
call sucess. So, problem did not get caught up.
This patch fixes the issue.
> Cc: stable@kernel.org [2.6.36+]
>
> Right? And then we could send it upstream.
Yes, sure. I think kishore can take care of adding this in 'cc'
while posting next time.
--
Regards,
Vimal Singh
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH] omap : nand : fix subpage ecc issue with prefetch
2011-05-06 7:30 ` Vimal Singh
@ 2011-05-06 18:56 ` Artem Bityutskiy
-1 siblings, 0 replies; 10+ messages in thread
From: Artem Bityutskiy @ 2011-05-06 18:56 UTC (permalink / raw)
To: Vimal Singh; +Cc: Kishore Kadiyala, linux-omap, linux-mtd, bdefaria
On Fri, 2011-05-06 at 13:00 +0530, Vimal Singh wrote:
> On Fri, May 6, 2011 at 12:18 AM, Artem Bityutskiy <dedekind1@gmail.com> wrote:
> > On Mon, 2011-05-02 at 16:40 +0530, Kishore Kadiyala wrote:
> >> For prefetch engine, read and write got broken in commit '2c01946c'.
> >> We never hit a scenario of not getting 'gpmc_prefetch_enable'
> >> call success.
> >> When reading/writing a subpage with a non divisible by 4 ecc number
> >> of bytes, the mis-aligned bytes gets handled first before enabling
> >> the Prefetch engine, then it reads/writes rest of the bytes.
> >>
> >> Signed-off-by: Kishore Kadiyala <kishore.kadiyala@ti.com>
> >> Signed-off-by: Vimal Singh <vimal.newwork@gmail.com>
> >> Reported-by: Bryan DE FARIA <bdefaria@adeneo-embedded.com>
> >
> > This needs a better commit message with more explanation and analysis of
> > the problem and how it was fixed.This commit message is not very
> > understandable. And then it needs also:
>
> How about a commit log like this:
Looks better, thanks. Waiting for the new patch.
>
> When reading/writing a subpage (When HW ECC is not available/enable)
> for number of bytes not aligned to 4, the mis-aligned bytes gets
> handled first (by cpu copy mathod) before enabling the Prefetch
> engin to/from 'p' (start of buffer 'buf').
> Then it reads/writes rest of the bytes with the help of Prefetch
> engine, if available, or again by cpu copy mathod. Currnetly,
> reading/writing of rest of bytes, is not done correctly. Its trying to
> read/write again to/from begining of buffer 'buf', overwriting the
> mis-aligned bytes.
>
> For prefetch engine read and write it got broken in commit '2c01946c'.
> And we never hit the scenario of not getting 'gpmc_prefetch_enable'
> call sucess. So, problem did not get caught up.
>
> This patch fixes the issue.
--
Best Regards,
Artem Bityutskiy (Артём Битюцкий)
--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH] omap : nand : fix subpage ecc issue with prefetch
@ 2011-05-06 18:56 ` Artem Bityutskiy
0 siblings, 0 replies; 10+ messages in thread
From: Artem Bityutskiy @ 2011-05-06 18:56 UTC (permalink / raw)
To: Vimal Singh; +Cc: bdefaria, linux-mtd, linux-omap, Kishore Kadiyala
On Fri, 2011-05-06 at 13:00 +0530, Vimal Singh wrote:
> On Fri, May 6, 2011 at 12:18 AM, Artem Bityutskiy <dedekind1@gmail.com> wrote:
> > On Mon, 2011-05-02 at 16:40 +0530, Kishore Kadiyala wrote:
> >> For prefetch engine, read and write got broken in commit '2c01946c'.
> >> We never hit a scenario of not getting 'gpmc_prefetch_enable'
> >> call success.
> >> When reading/writing a subpage with a non divisible by 4 ecc number
> >> of bytes, the mis-aligned bytes gets handled first before enabling
> >> the Prefetch engine, then it reads/writes rest of the bytes.
> >>
> >> Signed-off-by: Kishore Kadiyala <kishore.kadiyala@ti.com>
> >> Signed-off-by: Vimal Singh <vimal.newwork@gmail.com>
> >> Reported-by: Bryan DE FARIA <bdefaria@adeneo-embedded.com>
> >
> > This needs a better commit message with more explanation and analysis of
> > the problem and how it was fixed.This commit message is not very
> > understandable. And then it needs also:
>
> How about a commit log like this:
Looks better, thanks. Waiting for the new patch.
>
> When reading/writing a subpage (When HW ECC is not available/enable)
> for number of bytes not aligned to 4, the mis-aligned bytes gets
> handled first (by cpu copy mathod) before enabling the Prefetch
> engin to/from 'p' (start of buffer 'buf').
> Then it reads/writes rest of the bytes with the help of Prefetch
> engine, if available, or again by cpu copy mathod. Currnetly,
> reading/writing of rest of bytes, is not done correctly. Its trying to
> read/write again to/from begining of buffer 'buf', overwriting the
> mis-aligned bytes.
>
> For prefetch engine read and write it got broken in commit '2c01946c'.
> And we never hit the scenario of not getting 'gpmc_prefetch_enable'
> call sucess. So, problem did not get caught up.
>
> This patch fixes the issue.
--
Best Regards,
Artem Bityutskiy (Артём Битюцкий)
^ permalink raw reply [flat|nested] 10+ messages in thread
end of thread, other threads:[~2011-05-06 18:59 UTC | newest]
Thread overview: 10+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2011-05-02 11:10 [PATCH] omap : nand : fix subpage ecc issue with prefetch Kishore Kadiyala
2011-05-02 11:10 ` Kishore Kadiyala
2011-05-05 14:20 ` Vimal Singh
2011-05-05 14:20 ` Vimal Singh
2011-05-05 18:48 ` Artem Bityutskiy
2011-05-05 18:48 ` Artem Bityutskiy
2011-05-06 7:30 ` Vimal Singh
2011-05-06 7:30 ` Vimal Singh
2011-05-06 18:56 ` Artem Bityutskiy
2011-05-06 18:56 ` Artem Bityutskiy
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