[PATCH] mtd: gpmi: Always report ECC stats and return max_bitflips

[PATCH] mtd: gpmi: Always report ECC stats and return max_bitflips

[Zach Sadecki]

Always report corrected and failed ECC stats back up to the MTD layer.  Also
return max_bitflips from read_page() as is expected from NAND drivers now.

Signed-off-by: Zach Sadecki <zsadecki@itwatchdogs.com>
---
   drivers/mtd/nand/gpmi-nand/gpmi-nand.c |   27 ++++++++-------------------
   1 file changed, 8 insertions(+), 19 deletions(-)

diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
index d79696b..fe10c53 100644
--- a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
+++ b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
@@ -914,8 +914,7 @@ static int gpmi_ecc_read_page(struct mtd_info *mtd, struct nand_chip *chip,
   	dma_addr_t    auxiliary_phys;
   	unsigned int  i;
   	unsigned char *status;
-	unsigned int  failed;
-	unsigned int  corrected;
+	unsigned int  max_bitflips = 0;
   	int           ret;
   
   	pr_debug("page number is : %d\n", page);
@@ -939,35 +938,25 @@ static int gpmi_ecc_read_page(struct mtd_info *mtd, struct nand_chip *chip,
   			payload_virt, payload_phys);
   	if (ret) {
   		pr_err("Error in ECC-based read: %d\n", ret);
-		goto exit_nfc;
+		return ret;
   	}
   
   	/* handle the block mark swapping */
   	block_mark_swapping(this, payload_virt, auxiliary_virt);
   
   	/* Loop over status bytes, accumulating ECC status. */
-	failed		= 0;
-	corrected	= 0;
-	status		= auxiliary_virt + nfc_geo->auxiliary_status_offset;
+	status = auxiliary_virt + nfc_geo->auxiliary_status_offset;
   
   	for (i = 0; i < nfc_geo->ecc_chunk_count; i++, status++) {
   		if ((*status == STATUS_GOOD) || (*status == STATUS_ERASED))
   			continue;
   
   		if (*status == STATUS_UNCORRECTABLE) {
-			failed++;
+			mtd->ecc_stats.failed++;
   			continue;
   		}
-		corrected += *status;
-	}
-
-	/*
-	 * Propagate ECC status to the owning MTD only when failed or
-	 * corrected times nearly reaches our ECC correction threshold.
-	 */
-	if (failed || corrected >= (nfc_geo->ecc_strength - 1)) {
-		mtd->ecc_stats.failed    += failed;
-		mtd->ecc_stats.corrected += corrected;
+		mtd->ecc_stats.corrected += *status;
+		max_bitflips = max_t(unsigned int, max_bitflips, *status);
   	}
   
   	if (oob_required) {
@@ -989,8 +978,8 @@ static int gpmi_ecc_read_page(struct mtd_info *mtd, struct nand_chip *chip,
   			this->payload_virt, this->payload_phys,
   			nfc_geo->payload_size,
   			payload_virt, payload_phys);
-exit_nfc:
-	return ret;
+
+	return max_bitflips;
   }
   
   static int gpmi_ecc_write_page(struct mtd_info *mtd, struct nand_chip *chip,
-- 
1.7.9.5

Re: [PATCH] mtd: gpmi: Always report ECC stats and return max_bitflips

[Huang Shijie]

于 2012年12月04日 03:48, Zach Sadecki 写道:
> Always report corrected and failed ECC stats back up to the MTD layer. 
> Also
> return max_bitflips from read_page() as is expected from NAND drivers 
> now.
>
> Signed-off-by: Zach Sadecki <zsadecki@itwatchdogs.com>
> ---
> drivers/mtd/nand/gpmi-nand/gpmi-nand.c | 27 ++++++++-------------------
> 1 file changed, 8 insertions(+), 19 deletions(-)
>
> diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c 
> b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
> index d79696b..fe10c53 100644
> --- a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
> +++ b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
> @@ -914,8 +914,7 @@ static int gpmi_ecc_read_page(struct mtd_info 
> *mtd, struct nand_chip *chip,
> dma_addr_t auxiliary_phys;
> unsigned int i;
> unsigned char *status;
> - unsigned int failed;
> - unsigned int corrected;
> + unsigned int max_bitflips = 0;
> int ret;
> pr_debug("page number is : %d\n", page);
> @@ -939,35 +938,25 @@ static int gpmi_ecc_read_page(struct mtd_info 
> *mtd, struct nand_chip *chip,
> payload_virt, payload_phys);
> if (ret) {
> pr_err("Error in ECC-based read: %d\n", ret);
> - goto exit_nfc;
> + return ret;
> }
> /* handle the block mark swapping */
> block_mark_swapping(this, payload_virt, auxiliary_virt);
> /* Loop over status bytes, accumulating ECC status. */
> - failed = 0;
> - corrected = 0;
> - status = auxiliary_virt + nfc_geo->auxiliary_status_offset;
> + status = auxiliary_virt + nfc_geo->auxiliary_status_offset;
> for (i = 0; i < nfc_geo->ecc_chunk_count; i++, status++) {
> if ((*status == STATUS_GOOD) || (*status == STATUS_ERASED))
> continue;
> if (*status == STATUS_UNCORRECTABLE) {
> - failed++;
> + mtd->ecc_stats.failed++;
> continue;
> }
> - corrected += *status;
> - }
> -
> - /*
> - * Propagate ECC status to the owning MTD only when failed or
> - * corrected times nearly reaches our ECC correction threshold.
> - */
> - if (failed || corrected >= (nfc_geo->ecc_strength - 1)) {
> - mtd->ecc_stats.failed += failed;
> - mtd->ecc_stats.corrected += corrected;
> + mtd->ecc_stats.corrected += *status;
> + max_bitflips = max_t(unsigned int, max_bitflips, *status);

Does the max_bitflips stand for the whole page's bitfips ? or just the 
bitfips of one part of the page?
The gpmi driver splits a page into several parts when it does the ECC.

thanks
Huang Shijie


> }
> if (oob_required) {
> @@ -989,8 +978,8 @@ static int gpmi_ecc_read_page(struct mtd_info 
> *mtd, struct nand_chip *chip,
> this->payload_virt, this->payload_phys,
> nfc_geo->payload_size,
> payload_virt, payload_phys);
> -exit_nfc:
> - return ret;
> +
> + return max_bitflips;
> }
> static int gpmi_ecc_write_page(struct mtd_info *mtd, struct nand_chip 
> *chip,

Re: [PATCH] mtd: gpmi: Always report ECC stats and return max_bitflips

[Zach Sadecki]

On 12/03/2012 09:34 PM, Huang Shijie wrote:
> 于 2012年12月04日 03:48, Zach Sadecki 写道:
>> Always report corrected and failed ECC stats back up to the MTD 
>> layer. Also
>> return max_bitflips from read_page() as is expected from NAND drivers 
>> now.
>>
>> Signed-off-by: Zach Sadecki <zsadecki@itwatchdogs.com>
>> ---
>> drivers/mtd/nand/gpmi-nand/gpmi-nand.c | 27 ++++++++-------------------
>> 1 file changed, 8 insertions(+), 19 deletions(-)
>>
>> diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c 
>> b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
>> index d79696b..fe10c53 100644
>> --- a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
>> +++ b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
>> @@ -914,8 +914,7 @@ static int gpmi_ecc_read_page(struct mtd_info 
>> *mtd, struct nand_chip *chip,
>> dma_addr_t auxiliary_phys;
>> unsigned int i;
>> unsigned char *status;
>> - unsigned int failed;
>> - unsigned int corrected;
>> + unsigned int max_bitflips = 0;
>> int ret;
>> pr_debug("page number is : %d\n", page);
>> @@ -939,35 +938,25 @@ static int gpmi_ecc_read_page(struct mtd_info 
>> *mtd, struct nand_chip *chip,
>> payload_virt, payload_phys);
>> if (ret) {
>> pr_err("Error in ECC-based read: %d\n", ret);
>> - goto exit_nfc;
>> + return ret;
>> }
>> /* handle the block mark swapping */
>> block_mark_swapping(this, payload_virt, auxiliary_virt);
>> /* Loop over status bytes, accumulating ECC status. */
>> - failed = 0;
>> - corrected = 0;
>> - status = auxiliary_virt + nfc_geo->auxiliary_status_offset;
>> + status = auxiliary_virt + nfc_geo->auxiliary_status_offset;
>> for (i = 0; i < nfc_geo->ecc_chunk_count; i++, status++) {
>> if ((*status == STATUS_GOOD) || (*status == STATUS_ERASED))
>> continue;
>> if (*status == STATUS_UNCORRECTABLE) {
>> - failed++;
>> + mtd->ecc_stats.failed++;
>> continue;
>> }
>> - corrected += *status;
>> - }
>> -
>> - /*
>> - * Propagate ECC status to the owning MTD only when failed or
>> - * corrected times nearly reaches our ECC correction threshold.
>> - */
>> - if (failed || corrected >= (nfc_geo->ecc_strength - 1)) {
>> - mtd->ecc_stats.failed += failed;
>> - mtd->ecc_stats.corrected += corrected;
>> + mtd->ecc_stats.corrected += *status;
>> + max_bitflips = max_t(unsigned int, max_bitflips, *status);
>
> Does the max_bitflips stand for the whole page's bitfips ? or just the 
> bitfips of one part of the page?
> The gpmi driver splits a page into several parts when it does the ECC.
>
> thanks
> Huang Shijie
>
max_bitflips represents the maximum number of bitflips per ECC corrected 
region in a page.  The MTD layer needs it to compare to 
bitflip_threshold to know when to return -EUCLEAN to upper layers (like 
UBI) so a nearly corrupt page can be copied elsewhere.  This is pretty 
much identical to the way other drivers do this as I copied it from 
those.  Here's where it was added in the other drivers: 
http://git.infradead.org/linux-mtd.git/commit/3f91e94f7f511de74c0d2abe08672ccdbdd1961c 


Zach
>
>> }
>> if (oob_required) {
>> @@ -989,8 +978,8 @@ static int gpmi_ecc_read_page(struct mtd_info 
>> *mtd, struct nand_chip *chip,
>> this->payload_virt, this->payload_phys,
>> nfc_geo->payload_size,
>> payload_virt, payload_phys);
>> -exit_nfc:
>> - return ret;
>> +
>> + return max_bitflips;
>> }
>> static int gpmi_ecc_write_page(struct mtd_info *mtd, struct nand_chip 
>> *chip,
>
>

Re: [PATCH] mtd: gpmi: Always report ECC stats and return max_bitflips

[Huang Shijie]

于 2012年12月04日 22:40, Zach Sadecki 写道:
> max_bitflips represents the maximum number of bitflips per ECC 
> corrected region in a page. 
got it.

I also tested this patch in the mx6q-arm2 board. it runned well.

thanks.

Acked-by: Huang Shijie <b32955@freescale.com>


Huang Shijie

Re: [PATCH] mtd: gpmi: Always report ECC stats and return max_bitflips

[Artem Bityutskiy]

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On Mon, 2012-12-03 at 13:48 -0600, Zach Sadecki wrote:
> Always report corrected and failed ECC stats back up to the MTD layer.  Also
> return max_bitflips from read_page() as is expected from NAND drivers now.
> 
> Signed-off-by: Zach Sadecki <zsadecki@itwatchdogs.com>

Could you please send a version which applies cleanly to the l2-mtd.git
tree? Thanks!

git://git.infradead.org/users/dedekind/l2-mtd.git

-- 
Best Regards,
Artem Bityutskiy

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[PATCH] mtd: gpmi: Always report ECC stats and return max_bitflips

[Zach Sadecki]

Always report corrected and failed ECC stats back up to the MTD layer.  Also
return max_bitflips from read_page() as is expected from NAND drivers now.

Signed-off-by: Zach Sadecki <zsadecki@itwatchdogs.com>
Acked-by: Huang Shijie <b32955@freescale.com>
---
  drivers/mtd/nand/gpmi-nand/gpmi-nand.c |   27 ++++++++-------------------
  1 file changed, 8 insertions(+), 19 deletions(-)

diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c 
b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
index 5cd141f..1535bd5 100644
--- a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
+++ b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
@@ -921,8 +921,7 @@ static int gpmi_ecc_read_page(struct mtd_info *mtd, 
struct nand_chip *chip,
      dma_addr_t    auxiliary_phys;
      unsigned int  i;
      unsigned char *status;
-    unsigned int  failed;
-    unsigned int  corrected;
+    unsigned int  max_bitflips = 0;
      int           ret;

      pr_debug("page number is : %d\n", page);
@@ -946,35 +945,25 @@ static int gpmi_ecc_read_page(struct mtd_info 
*mtd, struct nand_chip *chip,
              payload_virt, payload_phys);
      if (ret) {
          pr_err("Error in ECC-based read: %d\n", ret);
-        goto exit_nfc;
+        return ret;
      }

      /* handle the block mark swapping */
      block_mark_swapping(this, payload_virt, auxiliary_virt);

      /* Loop over status bytes, accumulating ECC status. */
-    failed        = 0;
-    corrected    = 0;
-    status        = auxiliary_virt + nfc_geo->auxiliary_status_offset;
+    status = auxiliary_virt + nfc_geo->auxiliary_status_offset;

      for (i = 0; i < nfc_geo->ecc_chunk_count; i++, status++) {
          if ((*status == STATUS_GOOD) || (*status == STATUS_ERASED))
              continue;

          if (*status == STATUS_UNCORRECTABLE) {
-            failed++;
+            mtd->ecc_stats.failed++;
              continue;
          }
-        corrected += *status;
-    }
-
-    /*
-     * Propagate ECC status to the owning MTD only when failed or
-     * corrected times nearly reaches our ECC correction threshold.
-     */
-    if (failed || corrected >= (nfc_geo->ecc_strength - 1)) {
-        mtd->ecc_stats.failed    += failed;
-        mtd->ecc_stats.corrected += corrected;
+        mtd->ecc_stats.corrected += *status;
+        max_bitflips = max_t(unsigned int, max_bitflips, *status);
      }

      if (oob_required) {
@@ -996,8 +985,8 @@ static int gpmi_ecc_read_page(struct mtd_info *mtd, 
struct nand_chip *chip,
              this->payload_virt, this->payload_phys,
              nfc_geo->payload_size,
              payload_virt, payload_phys);
-exit_nfc:
-    return ret;
+
+    return max_bitflips;
  }

  static int gpmi_ecc_write_page(struct mtd_info *mtd, struct nand_chip 
*chip,
-- 
1.7.9.5

[PATCH] mtd: gpmi: Always report ECC stats and return max_bitflips

[Zach Sadecki]

Always report corrected and failed ECC stats back up to the MTD layer.  Also
return max_bitflips from read_page() as is expected from NAND drivers now.

Signed-off-by: Zach Sadecki <zsadecki@itwatchdogs.com>
Acked-by: Huang Shijie <b32955 at freescale.com>
---
  drivers/mtd/nand/gpmi-nand/gpmi-nand.c |   27 ++++++++-------------------
  1 file changed, 8 insertions(+), 19 deletions(-)

diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
index 5cd141f..1535bd5 100644
--- a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
+++ b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
@@ -921,8 +921,7 @@ static int gpmi_ecc_read_page(struct mtd_info *mtd, struct nand_chip *chip,
  	dma_addr_t    auxiliary_phys;
  	unsigned int  i;
  	unsigned char *status;
-	unsigned int  failed;
-	unsigned int  corrected;
+	unsigned int  max_bitflips = 0;
  	int           ret;
  
  	pr_debug("page number is : %d\n", page);
@@ -946,35 +945,25 @@ static int gpmi_ecc_read_page(struct mtd_info *mtd, struct nand_chip *chip,
  			payload_virt, payload_phys);
  	if (ret) {
  		pr_err("Error in ECC-based read: %d\n", ret);
-		goto exit_nfc;
+		return ret;
  	}
  
  	/* handle the block mark swapping */
  	block_mark_swapping(this, payload_virt, auxiliary_virt);
  
  	/* Loop over status bytes, accumulating ECC status. */
-	failed		= 0;
-	corrected	= 0;
-	status		= auxiliary_virt + nfc_geo->auxiliary_status_offset;
+	status = auxiliary_virt + nfc_geo->auxiliary_status_offset;
  
  	for (i = 0; i < nfc_geo->ecc_chunk_count; i++, status++) {
  		if ((*status == STATUS_GOOD) || (*status == STATUS_ERASED))
  			continue;
  
  		if (*status == STATUS_UNCORRECTABLE) {
-			failed++;
+			mtd->ecc_stats.failed++;
  			continue;
  		}
-		corrected += *status;
-	}
-
-	/*
-	 * Propagate ECC status to the owning MTD only when failed or
-	 * corrected times nearly reaches our ECC correction threshold.
-	 */
-	if (failed || corrected >= (nfc_geo->ecc_strength - 1)) {
-		mtd->ecc_stats.failed    += failed;
-		mtd->ecc_stats.corrected += corrected;
+		mtd->ecc_stats.corrected += *status;
+		max_bitflips = max_t(unsigned int, max_bitflips, *status);
  	}
  
  	if (oob_required) {
@@ -996,8 +985,8 @@ static int gpmi_ecc_read_page(struct mtd_info *mtd, struct nand_chip *chip,
  			this->payload_virt, this->payload_phys,
  			nfc_geo->payload_size,
  			payload_virt, payload_phys);
-exit_nfc:
-	return ret;
+
+	return max_bitflips;
  }
  
  static int gpmi_ecc_write_page(struct mtd_info *mtd, struct nand_chip *chip,
-- 
1.7.9.5

Re: [PATCH] mtd: gpmi: Always report ECC stats and return max_bitflips

[Artem Bityutskiy]

[-- Attachment #1: Type: text/plain, Size: 730 bytes --]

On Mon, 2012-12-10 at 09:18 -0600, Zach Sadecki wrote:
> Always report corrected and failed ECC stats back up to the MTD layer.  Also
> return max_bitflips from read_page() as is expected from NAND drivers now.
> 
> Signed-off-by: Zach Sadecki <zsadecki@itwatchdogs.com>
> Acked-by: Huang Shijie <b32955 at freescale.com>
> ---
>   drivers/mtd/nand/gpmi-nand/gpmi-nand.c |   27 ++++++++-------------------
>   1 file changed, 8 insertions(+), 19 deletions(-)

patching file drivers/mtd/nand/gpmi-nand/gpmi-nand.c
Hunk #1 FAILED at 921.
Hunk #2 FAILED at 946.
Hunk #3 FAILED at 996.
3 out of 3 hunks FAILED -- saving rejects to file drivers/mtd/nand/gpmi-nand/gpmi-nand.c.rej

-- 
Best Regards,
Artem Bityutskiy

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Re: [PATCH] mtd: gpmi: Always report ECC stats and return max_bitflips

[Zach Sadecki]

On 12/12/2012 09:17 AM, Artem Bityutskiy wrote:
> patching file drivers/mtd/nand/gpmi-nand/gpmi-nand.c
> Hunk #1 FAILED at 921.
> Hunk #2 FAILED at 946.
> Hunk #3 FAILED at 996.
> 3 out of 3 hunks FAILED -- saving rejects to file drivers/mtd/nand/gpmi-nand/gpmi-nand.c.rej
>
Odd.  I used git format-patch on a freshly cloned l2-mtd repo...  I 
don't know what could be wrong.  I did a fresh pull, and another git 
format-patch and it generated the exact same patch file.  Any ideas?

Re: [PATCH] mtd: gpmi: Always report ECC stats and return max_bitflips

[Artem Bityutskiy]

[-- Attachment #1.1: Type: text/plain, Size: 802 bytes --]

On Mon, 2012-12-10 at 09:18 -0600, Zach Sadecki wrote:
> Always report corrected and failed ECC stats back up to the MTD layer.  Also
> return max_bitflips from read_page() as is expected from NAND drivers now.
> 
> Signed-off-by: Zach Sadecki <zsadecki@itwatchdogs.com>
> Acked-by: Huang Shijie <b32955 at freescale.com>
> ---

Dunno, may be your patch is corrupted or something. Try to save it and
apply. This is what I get:

$ git apply --check ~/tmp/zach.mbox
error: patch failed: drivers/mtd/nand/gpmi-nand/gpmi-nand.c:921
error: drivers/mtd/nand/gpmi-nand/gpmi-nand.c: patch does not apply

$ git log -1 --oneline
70df8b3 mtd: nand: gpmi: reset BCH earlier, too, to avoid NAND startup problems

I've attached the zach.mbox file for you.

-- 
Best Regards,
Artem Bityutskiy

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[PATCH] mtd: gpmi: Always report ECC stats and return max_bitflips

[Zach Sadecki]

Always report corrected and failed ECC stats back up to the MTD layer.  Also
return max_bitflips from read_page() as is expected from NAND drivers now.

Signed-off-by: Zach Sadecki <zsadecki@itwatchdogs.com>
Acked-by: Huang Shijie <b32955 at freescale.com>
---
  drivers/mtd/nand/gpmi-nand/gpmi-nand.c |   27 ++++++++-------------------
  1 file changed, 8 insertions(+), 19 deletions(-)

diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
index 5cd141f..1535bd5 100644
--- a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
+++ b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
@@ -921,8 +921,7 @@ static int gpmi_ecc_read_page(struct mtd_info *mtd, struct nand_chip *chip,
  	dma_addr_t    auxiliary_phys;
  	unsigned int  i;
  	unsigned char *status;
-	unsigned int  failed;
-	unsigned int  corrected;
+	unsigned int  max_bitflips = 0;
  	int           ret;
  
  	pr_debug("page number is : %d\n", page);
@@ -946,35 +945,25 @@ static int gpmi_ecc_read_page(struct mtd_info *mtd, struct nand_chip *chip,
  			payload_virt, payload_phys);
  	if (ret) {
  		pr_err("Error in ECC-based read: %d\n", ret);
-		goto exit_nfc;
+		return ret;
  	}
  
  	/* handle the block mark swapping */
  	block_mark_swapping(this, payload_virt, auxiliary_virt);
  
  	/* Loop over status bytes, accumulating ECC status. */
-	failed		= 0;
-	corrected	= 0;
-	status		= auxiliary_virt + nfc_geo->auxiliary_status_offset;
+	status = auxiliary_virt + nfc_geo->auxiliary_status_offset;
  
  	for (i = 0; i < nfc_geo->ecc_chunk_count; i++, status++) {
  		if ((*status == STATUS_GOOD) || (*status == STATUS_ERASED))
  			continue;
  
  		if (*status == STATUS_UNCORRECTABLE) {
-			failed++;
+			mtd->ecc_stats.failed++;
  			continue;
  		}
-		corrected += *status;
-	}
-
-	/*
-	 * Propagate ECC status to the owning MTD only when failed or
-	 * corrected times nearly reaches our ECC correction threshold.
-	 */
-	if (failed || corrected >= (nfc_geo->ecc_strength - 1)) {
-		mtd->ecc_stats.failed    += failed;
-		mtd->ecc_stats.corrected += corrected;
+		mtd->ecc_stats.corrected += *status;
+		max_bitflips = max_t(unsigned int, max_bitflips, *status);
  	}
  
  	if (oob_required) {
@@ -996,8 +985,8 @@ static int gpmi_ecc_read_page(struct mtd_info *mtd, struct nand_chip *chip,
  			this->payload_virt, this->payload_phys,
  			nfc_geo->payload_size,
  			payload_virt, payload_phys);
-exit_nfc:
-	return ret;
+
+	return max_bitflips;
  }
  
  static int gpmi_ecc_write_page(struct mtd_info *mtd, struct nand_chip *chip,
-- 
1.7.9.5

[PATCH] mtd: gpmi: Always report ECC stats and return max_bitflips

[Zach Sadecki]

Always report corrected and failed ECC stats back up to the MTD layer.  Also
return max_bitflips from read_page() as is expected from NAND drivers now.

Signed-off-by: Zach Sadecki <zsadecki@itwatchdogs.com>
Acked-by: Huang Shijie <b32955@freescale.com>
---
  drivers/mtd/nand/gpmi-nand/gpmi-nand.c |   27 ++++++++-------------------
  1 file changed, 8 insertions(+), 19 deletions(-)

diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
index 5cd141f..1535bd5 100644
--- a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
+++ b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
@@ -921,8 +921,7 @@ static int gpmi_ecc_read_page(struct mtd_info *mtd, struct nand_chip *chip,
  	dma_addr_t    auxiliary_phys;
  	unsigned int  i;
  	unsigned char *status;
-	unsigned int  failed;
-	unsigned int  corrected;
+	unsigned int  max_bitflips = 0;
  	int           ret;
  
  	pr_debug("page number is : %d\n", page);
@@ -946,35 +945,25 @@ static int gpmi_ecc_read_page(struct mtd_info *mtd, struct nand_chip *chip,
  			payload_virt, payload_phys);
  	if (ret) {
  		pr_err("Error in ECC-based read: %d\n", ret);
-		goto exit_nfc;
+		return ret;
  	}
  
  	/* handle the block mark swapping */
  	block_mark_swapping(this, payload_virt, auxiliary_virt);
  
  	/* Loop over status bytes, accumulating ECC status. */
-	failed		= 0;
-	corrected	= 0;
-	status		= auxiliary_virt + nfc_geo->auxiliary_status_offset;
+	status = auxiliary_virt + nfc_geo->auxiliary_status_offset;
  
  	for (i = 0; i < nfc_geo->ecc_chunk_count; i++, status++) {
  		if ((*status == STATUS_GOOD) || (*status == STATUS_ERASED))
  			continue;
  
  		if (*status == STATUS_UNCORRECTABLE) {
-			failed++;
+			mtd->ecc_stats.failed++;
  			continue;
  		}
-		corrected += *status;
-	}
-
-	/*
-	 * Propagate ECC status to the owning MTD only when failed or
-	 * corrected times nearly reaches our ECC correction threshold.
-	 */
-	if (failed || corrected >= (nfc_geo->ecc_strength - 1)) {
-		mtd->ecc_stats.failed    += failed;
-		mtd->ecc_stats.corrected += corrected;
+		mtd->ecc_stats.corrected += *status;
+		max_bitflips = max_t(unsigned int, max_bitflips, *status);
  	}
  
  	if (oob_required) {
@@ -996,8 +985,8 @@ static int gpmi_ecc_read_page(struct mtd_info *mtd, struct nand_chip *chip,
  			this->payload_virt, this->payload_phys,
  			nfc_geo->payload_size,
  			payload_virt, payload_phys);
-exit_nfc:
-	return ret;
+
+	return max_bitflips;
  }
  
  static int gpmi_ecc_write_page(struct mtd_info *mtd, struct nand_chip *chip,
-- 
1.7.9.5

Re: [PATCH] mtd: gpmi: Always report ECC stats and return max_bitflips

[Huang Shijie]

于 2012年12月14日 10:36, Zach Sadecki 写道:
> Always report corrected and failed ECC stats back up to the MTD layer. 
> Also
> return max_bitflips from read_page() as is expected from NAND drivers 
> now.
>
> Signed-off-by: Zach Sadecki <zsadecki@itwatchdogs.com>
> Acked-by: Huang Shijie <b32955@freescale.com>
> ---
> drivers/mtd/nand/gpmi-nand/gpmi-nand.c | 27 ++++++++-------------------
> 1 file changed, 8 insertions(+), 19 deletions(-)
>
> diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c 
> b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
> index 5cd141f..1535bd5 100644
> --- a/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
> +++ b/drivers/mtd/nand/gpmi-nand/gpmi-nand.c
> @@ -921,8 +921,7 @@ static int gpmi_ecc_read_page(struct mtd_info 
> *mtd, struct nand_chip *chip,
> dma_addr_t auxiliary_phys;
> unsigned int i;
> unsigned char *status;
> - unsigned int failed;
> - unsigned int corrected;
> + unsigned int max_bitflips = 0;
> int ret;
>
> pr_debug("page number is : %d\n", page);
> @@ -946,35 +945,25 @@ static int gpmi_ecc_read_page(struct mtd_info 
> *mtd, struct nand_chip *chip,
> payload_virt, payload_phys);
> if (ret) {
> pr_err("Error in ECC-based read: %d\n", ret);
> - goto exit_nfc;
> + return ret;
> }
>
> /* handle the block mark swapping */
> block_mark_swapping(this, payload_virt, auxiliary_virt);
>
> /* Loop over status bytes, accumulating ECC status. */
> - failed = 0;
> - corrected = 0;
> - status = auxiliary_virt + nfc_geo->auxiliary_status_offset;
> + status = auxiliary_virt + nfc_geo->auxiliary_status_offset;
>
> for (i = 0; i < nfc_geo->ecc_chunk_count; i++, status++) {
> if ((*status == STATUS_GOOD) || (*status == STATUS_ERASED))
> continue;
>
> if (*status == STATUS_UNCORRECTABLE) {
> - failed++;
> + mtd->ecc_stats.failed++;
> continue;
> }
> - corrected += *status;
> - }
> -
> - /*
> - * Propagate ECC status to the owning MTD only when failed or
> - * corrected times nearly reaches our ECC correction threshold.
> - */
> - if (failed || corrected >= (nfc_geo->ecc_strength - 1)) {
> - mtd->ecc_stats.failed += failed;
> - mtd->ecc_stats.corrected += corrected;
> + mtd->ecc_stats.corrected += *status;
> + max_bitflips = max_t(unsigned int, max_bitflips, *status);
> }
>
> if (oob_required) {
> @@ -996,8 +985,8 @@ static int gpmi_ecc_read_page(struct mtd_info 
> *mtd, struct nand_chip *chip,
> this->payload_virt, this->payload_phys,
> nfc_geo->payload_size,
> payload_virt, payload_phys);
> -exit_nfc:
> - return ret;
> +
> + return max_bitflips;
> }
>
> static int gpmi_ecc_write_page(struct mtd_info *mtd, struct nand_chip 
> *chip,
just a ping.

Re: [PATCH] mtd: gpmi: Always report ECC stats and return max_bitflips

[Artem Bityutskiy]

[-- Attachment #1: Type: text/plain, Size: 398 bytes --]

On Thu, 2012-12-13 at 20:36 -0600, Zach Sadecki wrote:
> Always report corrected and failed ECC stats back up to the MTD layer.  Also
> return max_bitflips from read_page() as is expected from NAND drivers now.
> 
> Signed-off-by: Zach Sadecki <zsadecki@itwatchdogs.com>
> Acked-by: Huang Shijie <b32955@freescale.com>

Pushed to l2-mtd.git, thanks!

-- 
Best Regards,
Artem Bityutskiy

[-- Attachment #2: This is a digitally signed message part --]
[-- Type: application/pgp-signature, Size: 836 bytes --]

Re: [PATCH] mtd: gpmi: Always report ECC stats and return max_bitflips

[Zach Sadecki]

On 12/13/2012 05:27 AM, Artem Bityutskiy wrote:
> On Mon, 2012-12-10 at 09:18 -0600, Zach Sadecki wrote:
>> Always report corrected and failed ECC stats back up to the MTD layer.  Also
>> return max_bitflips from read_page() as is expected from NAND drivers now.
>>
>> Signed-off-by: Zach Sadecki <zsadecki@itwatchdogs.com>
>> Acked-by: Huang Shijie <b32955 at freescale.com>
>> ---
> Dunno, may be your patch is corrupted or something. Try to save it and
> apply. This is what I get:
>
> $ git apply --check ~/tmp/zach.mbox
> error: patch failed: drivers/mtd/nand/gpmi-nand/gpmi-nand.c:921
> error: drivers/mtd/nand/gpmi-nand/gpmi-nand.c: patch does not apply
>
> $ git log -1 --oneline
> 70df8b3 mtd: nand: gpmi: reset BCH earlier, too, to avoid NAND startup problems
>
> I've attached the zach.mbox file for you.
>
OK.  I rebased the patch on the latest l2-mtd and I tested it with git 
apply, so this one should work...

Sent as a separate reply with only the patch in it.

Re: [PATCH] mtd: gpmi: Always report ECC stats and return max_bitflips

[Huang Shijie]

于 2012年12月14日 10:39, Zach Sadecki 写道:
> On 12/13/2012 05:27 AM, Artem Bityutskiy wrote:
>> On Mon, 2012-12-10 at 09:18 -0600, Zach Sadecki wrote:
>>> Always report corrected and failed ECC stats back up to the MTD 
>>> layer. Also
>>> return max_bitflips from read_page() as is expected from NAND 
>>> drivers now.
>>>
>>> Signed-off-by: Zach Sadecki <zsadecki@itwatchdogs.com>
>>> Acked-by: Huang Shijie <b32955 at freescale.com>
>>> ---
>> Dunno, may be your patch is corrupted or something. Try to save it and
>> apply. This is what I get:
>>
>> $ git apply --check ~/tmp/zach.mbox
>> error: patch failed: drivers/mtd/nand/gpmi-nand/gpmi-nand.c:921
>> error: drivers/mtd/nand/gpmi-nand/gpmi-nand.c: patch does not apply
>>
>> $ git log -1 --oneline
>> 70df8b3 mtd: nand: gpmi: reset BCH earlier, too, to avoid NAND 
>> startup problems
>>
>> I've attached the zach.mbox file for you.
>>
> OK. I rebased the patch on the latest l2-mtd and I tested it with git 
> apply, so this one should work...
>
> Sent as a separate reply with only the patch in it.
Dear Zach,
I think you'd better check the patch with /scripts/checkpatch.pl before 
you send out the patch.
I saw many "trailing whitespace" in your patch.

thanks.

Huang Shijie

Re: [PATCH] mtd: gpmi: Always report ECC stats and return max_bitflips

[Zach Sadecki]

On 01/09/2013 09:28 PM, Huang Shijie wrote:
> Dear Zach,
> I think you'd better check the patch with /scripts/checkpatch.pl 
> before you send out the patch.
> I saw many "trailing whitespace" in your patch.
>
> thanks.
>
> Huang Shijie 

I just checked it:

zach@zpc:~/git/l2-mtd$ scripts/checkpatch.pl 
0001-mtd-gpmi-Always-report-ECC-stats-and-return-max_bitf.patch
total: 0 errors, 0 warnings, 59 lines checked

0001-mtd-gpmi-Always-report-ECC-stats-and-return-max_bitf.patch has no 
obvious style problems and is ready for submission.

---

The reply to the original thread dated "Thu Dec 13 21:36:43 EST 2012" 
should be the correct patch...

Zach