diff mbox

[v3,06/16] mtd: rawnand: qcom: use the ecc strength from device parameter

Message ID 1527250904-21988-7-git-send-email-absahu@codeaurora.org (mailing list archive)
State Superseded, archived
Delegated to: Andy Gross
Headers show

Commit Message

Abhishek Sahu May 25, 2018, 12:21 p.m. UTC
Currently the driver uses the ECC strength specified in DT.
The QPIC/EBI2 NAND supports 4 or 8-bit ECC correction. The same
kind of board can have different NAND parts so use the ECC
strength from device parameters if it is not specified in DT.

Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
---
* Changes from v2:
  NONE

* Changes from v1:

  1. Removed the custom logic and used the helper fuction.

 drivers/mtd/nand/raw/qcom_nandc.c | 29 +++++++++++++++++++++--------
 1 file changed, 21 insertions(+), 8 deletions(-)

Comments

Miquel Raynal May 26, 2018, 8:43 a.m. UTC | #1
Hi Abhishek,

On Fri, 25 May 2018 17:51:34 +0530, Abhishek Sahu
<absahu@codeaurora.org> wrote:

> Currently the driver uses the ECC strength specified in DT.
> The QPIC/EBI2 NAND supports 4 or 8-bit ECC correction. The same
> kind of board can have different NAND parts so use the ECC
> strength from device parameters if it is not specified in DT.
> 
> Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
> ---
> * Changes from v2:
>   NONE

Yes you did change things:

- s/<< 2/* 4/
- updated the cwperpage location
- the block handling the ecc-step-size property has been removed in a
  previous patch

Please be careful with that, it is time consuming to review the patches
all over again.

> 
> * Changes from v1:
> 
>   1. Removed the custom logic and used the helper fuction.
> 
>  drivers/mtd/nand/raw/qcom_nandc.c | 29 +++++++++++++++++++++--------
>  1 file changed, 21 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/mtd/nand/raw/qcom_nandc.c b/drivers/mtd/nand/raw/qcom_nandc.c
> index b538390..7377923 100644
> --- a/drivers/mtd/nand/raw/qcom_nandc.c
> +++ b/drivers/mtd/nand/raw/qcom_nandc.c
> @@ -2315,19 +2315,39 @@ static int qcom_nand_ooblayout_free(struct mtd_info *mtd, int section,
>  	.free = qcom_nand_ooblayout_free,
>  };
>  
> +static int
> +qcom_nandc_calc_ecc_bytes(int step_size, int strength)
> +{
> +	return strength == 4 ? 12 : 16;
> +}
> +NAND_ECC_CAPS_SINGLE(qcom_nandc_ecc_caps, qcom_nandc_calc_ecc_bytes,
> +		     NANDC_STEP_SIZE, 4, 8);
> +
>  static int qcom_nand_host_setup(struct qcom_nand_host *host)
>  {
>  	struct nand_chip *chip = &host->chip;
>  	struct mtd_info *mtd = nand_to_mtd(chip);
>  	struct nand_ecc_ctrl *ecc = &chip->ecc;
>  	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
> -	int cwperpage, bad_block_byte;
> +	int cwperpage, bad_block_byte, ret;
>  	bool wide_bus;
>  	int ecc_mode = 1;
>  
>  	/* controller only supports 512 bytes of data in each step */
>  	ecc->size = NANDC_STEP_SIZE;
>  	wide_bus = chip->options & NAND_BUSWIDTH_16 ? true : false;
> +	cwperpage = mtd->writesize / NANDC_STEP_SIZE;
> +
> +	/*
> +	 * Each CW has 4 available OOB bytes which will be protected with ECC
> +	 * so remaining bytes can be used for ECC.
> +	 */
> +	ret = nand_ecc_choose_conf(chip, &qcom_nandc_ecc_caps,
> +				   mtd->oobsize - cwperpage * 4);

Nitpick: could you add parenthesis around (cwperpage * 4) just for
clarity.

> +	if (ret) {
> +		dev_err(nandc->dev, "No valid ECC settings possible\n");
> +		return ret;
> +	}
>  
>  	if (ecc->strength >= 8) {
>  		/* 8 bit ECC defaults to BCH ECC on all platforms */
> @@ -2396,7 +2416,6 @@ static int qcom_nand_host_setup(struct qcom_nand_host *host)
>  
>  	mtd_set_ooblayout(mtd, &qcom_nand_ooblayout_ops);
>  
> -	cwperpage = mtd->writesize / ecc->size;
>  	nandc->max_cwperpage = max_t(unsigned int, nandc->max_cwperpage,
>  				     cwperpage);
>  
> @@ -2412,12 +2431,6 @@ static int qcom_nand_host_setup(struct qcom_nand_host *host)
>  	 * for 8 bit ECC
>  	 */
>  	host->cw_size = host->cw_data + ecc->bytes;
> -
> -	if (ecc->bytes * (mtd->writesize / ecc->size) > mtd->oobsize) {
> -		dev_err(nandc->dev, "ecc data doesn't fit in OOB area\n");
> -		return -EINVAL;
> -	}
> -
>  	bad_block_byte = mtd->writesize - host->cw_size * (cwperpage - 1) + 1;
>  
>  	host->cfg0 = (cwperpage - 1) << CW_PER_PAGE

Once corrected:

Acked-by: Miquel Raynal <miquel.raynal@bootlin.com>

Thanks,
Miquèl
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Abhishek Sahu May 28, 2018, 6:01 a.m. UTC | #2
On 2018-05-26 14:13, Miquel Raynal wrote:
> Hi Abhishek,
> 
> On Fri, 25 May 2018 17:51:34 +0530, Abhishek Sahu
> <absahu@codeaurora.org> wrote:
> 
>> Currently the driver uses the ECC strength specified in DT.
>> The QPIC/EBI2 NAND supports 4 or 8-bit ECC correction. The same
>> kind of board can have different NAND parts so use the ECC
>> strength from device parameters if it is not specified in DT.
>> 
>> Signed-off-by: Abhishek Sahu <absahu@codeaurora.org>
>> ---
>> * Changes from v2:
>>   NONE
> 
> Yes you did change things:
> 
> - s/<< 2/* 4/
> - updated the cwperpage location
> - the block handling the ecc-step-size property has been removed in a
>   previous patch
> 
> Please be careful with that, it is time consuming to review the patches
> all over again.
> 

  Sorry Miquel for that.
  I Will pay more attention to this.
  I can understand the effort require in reviewing and how this can help
  in making review quicker.

>> 
>> * Changes from v1:
>> 
>>   1. Removed the custom logic and used the helper fuction.
>> 
>>  drivers/mtd/nand/raw/qcom_nandc.c | 29 +++++++++++++++++++++--------
>>  1 file changed, 21 insertions(+), 8 deletions(-)
>> 
>> diff --git a/drivers/mtd/nand/raw/qcom_nandc.c 
>> b/drivers/mtd/nand/raw/qcom_nandc.c
>> index b538390..7377923 100644
>> --- a/drivers/mtd/nand/raw/qcom_nandc.c
>> +++ b/drivers/mtd/nand/raw/qcom_nandc.c
>> @@ -2315,19 +2315,39 @@ static int qcom_nand_ooblayout_free(struct 
>> mtd_info *mtd, int section,
>>  	.free = qcom_nand_ooblayout_free,
>>  };
>> 
>> +static int
>> +qcom_nandc_calc_ecc_bytes(int step_size, int strength)
>> +{
>> +	return strength == 4 ? 12 : 16;
>> +}
>> +NAND_ECC_CAPS_SINGLE(qcom_nandc_ecc_caps, qcom_nandc_calc_ecc_bytes,
>> +		     NANDC_STEP_SIZE, 4, 8);
>> +
>>  static int qcom_nand_host_setup(struct qcom_nand_host *host)
>>  {
>>  	struct nand_chip *chip = &host->chip;
>>  	struct mtd_info *mtd = nand_to_mtd(chip);
>>  	struct nand_ecc_ctrl *ecc = &chip->ecc;
>>  	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
>> -	int cwperpage, bad_block_byte;
>> +	int cwperpage, bad_block_byte, ret;
>>  	bool wide_bus;
>>  	int ecc_mode = 1;
>> 
>>  	/* controller only supports 512 bytes of data in each step */
>>  	ecc->size = NANDC_STEP_SIZE;
>>  	wide_bus = chip->options & NAND_BUSWIDTH_16 ? true : false;
>> +	cwperpage = mtd->writesize / NANDC_STEP_SIZE;
>> +
>> +	/*
>> +	 * Each CW has 4 available OOB bytes which will be protected with 
>> ECC
>> +	 * so remaining bytes can be used for ECC.
>> +	 */
>> +	ret = nand_ecc_choose_conf(chip, &qcom_nandc_ecc_caps,
>> +				   mtd->oobsize - cwperpage * 4);
> 
> Nitpick: could you add parenthesis around (cwperpage * 4) just for
> clarity.
> 

  Thanks Miquel.
  I will update that.

  Regards,
  Abhishek

>> +	if (ret) {
>> +		dev_err(nandc->dev, "No valid ECC settings possible\n");
>> +		return ret;
>> +	}
>> 
>>  	if (ecc->strength >= 8) {
>>  		/* 8 bit ECC defaults to BCH ECC on all platforms */
>> @@ -2396,7 +2416,6 @@ static int qcom_nand_host_setup(struct 
>> qcom_nand_host *host)
>> 
>>  	mtd_set_ooblayout(mtd, &qcom_nand_ooblayout_ops);
>> 
>> -	cwperpage = mtd->writesize / ecc->size;
>>  	nandc->max_cwperpage = max_t(unsigned int, nandc->max_cwperpage,
>>  				     cwperpage);
>> 
>> @@ -2412,12 +2431,6 @@ static int qcom_nand_host_setup(struct 
>> qcom_nand_host *host)
>>  	 * for 8 bit ECC
>>  	 */
>>  	host->cw_size = host->cw_data + ecc->bytes;
>> -
>> -	if (ecc->bytes * (mtd->writesize / ecc->size) > mtd->oobsize) {
>> -		dev_err(nandc->dev, "ecc data doesn't fit in OOB area\n");
>> -		return -EINVAL;
>> -	}
>> -
>>  	bad_block_byte = mtd->writesize - host->cw_size * (cwperpage - 1) + 
>> 1;
>> 
>>  	host->cfg0 = (cwperpage - 1) << CW_PER_PAGE
> 
> Once corrected:
> 
> Acked-by: Miquel Raynal <miquel.raynal@bootlin.com>
> 
> Thanks,
> Miquèl
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diff mbox

Patch

diff --git a/drivers/mtd/nand/raw/qcom_nandc.c b/drivers/mtd/nand/raw/qcom_nandc.c
index b538390..7377923 100644
--- a/drivers/mtd/nand/raw/qcom_nandc.c
+++ b/drivers/mtd/nand/raw/qcom_nandc.c
@@ -2315,19 +2315,39 @@  static int qcom_nand_ooblayout_free(struct mtd_info *mtd, int section,
 	.free = qcom_nand_ooblayout_free,
 };
 
+static int
+qcom_nandc_calc_ecc_bytes(int step_size, int strength)
+{
+	return strength == 4 ? 12 : 16;
+}
+NAND_ECC_CAPS_SINGLE(qcom_nandc_ecc_caps, qcom_nandc_calc_ecc_bytes,
+		     NANDC_STEP_SIZE, 4, 8);
+
 static int qcom_nand_host_setup(struct qcom_nand_host *host)
 {
 	struct nand_chip *chip = &host->chip;
 	struct mtd_info *mtd = nand_to_mtd(chip);
 	struct nand_ecc_ctrl *ecc = &chip->ecc;
 	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
-	int cwperpage, bad_block_byte;
+	int cwperpage, bad_block_byte, ret;
 	bool wide_bus;
 	int ecc_mode = 1;
 
 	/* controller only supports 512 bytes of data in each step */
 	ecc->size = NANDC_STEP_SIZE;
 	wide_bus = chip->options & NAND_BUSWIDTH_16 ? true : false;
+	cwperpage = mtd->writesize / NANDC_STEP_SIZE;
+
+	/*
+	 * Each CW has 4 available OOB bytes which will be protected with ECC
+	 * so remaining bytes can be used for ECC.
+	 */
+	ret = nand_ecc_choose_conf(chip, &qcom_nandc_ecc_caps,
+				   mtd->oobsize - cwperpage * 4);
+	if (ret) {
+		dev_err(nandc->dev, "No valid ECC settings possible\n");
+		return ret;
+	}
 
 	if (ecc->strength >= 8) {
 		/* 8 bit ECC defaults to BCH ECC on all platforms */
@@ -2396,7 +2416,6 @@  static int qcom_nand_host_setup(struct qcom_nand_host *host)
 
 	mtd_set_ooblayout(mtd, &qcom_nand_ooblayout_ops);
 
-	cwperpage = mtd->writesize / ecc->size;
 	nandc->max_cwperpage = max_t(unsigned int, nandc->max_cwperpage,
 				     cwperpage);
 
@@ -2412,12 +2431,6 @@  static int qcom_nand_host_setup(struct qcom_nand_host *host)
 	 * for 8 bit ECC
 	 */
 	host->cw_size = host->cw_data + ecc->bytes;
-
-	if (ecc->bytes * (mtd->writesize / ecc->size) > mtd->oobsize) {
-		dev_err(nandc->dev, "ecc data doesn't fit in OOB area\n");
-		return -EINVAL;
-	}
-
 	bad_block_byte = mtd->writesize - host->cw_size * (cwperpage - 1) + 1;
 
 	host->cfg0 = (cwperpage - 1) << CW_PER_PAGE