[PATCH] mtd: rawnand: Ensure ECC configuration is propagated to upper layers

[Sascha Hauer]

Hi Miquel,

On Tue, May 07, 2024 at 10:58:42AM +0200, Miquel Raynal wrote:
> Until recently the "upper layer" was MTD. But following incremental
> reworks to bring spi-nand support and more recently generic ECC support,
> there is now an intermediate "generic NAND" layer that also needs to get
> access to some values. When using "converted" ECC engines, like the
> software ones, these values are already propagated correctly. But
> otherwise when using good old raw NAND controller drivers, we need to
> manually set these values ourselves at the end of the "scan" operation,
> once these values have been negotiated.
> 
> Without this propagation, later (generic) checks like the one warning
> users that the ECC strength is not high enough might simply no longer
> work.
> 
> Fixes: 8c126720fe10 ("mtd: rawnand: Use the ECC framework nand_ecc_is_strong_enough() helper")
> Cc: stable at vger.kernel.org
> Reported-by: Sascha Hauer <s.hauer at pengutronix.de>
> Closes: https://lore.kernel.org/all/Zhe2JtvvN1M4Ompw@pengutronix.de/
> Signed-off-by: Miquel Raynal <miquel.raynal at bootlin.com>
> ---
> 
> Hello Sascha, this is only compile tested, would you mind checking if
> that fixes your setup?

Works as expected:

Tested-by: Sascha Hauer <s.hauer at pengutronix.de>

Sascha

> Thanks, Miquèl
> 
>  drivers/mtd/nand/raw/nand_base.c | 9 ++++++++-
>  1 file changed, 8 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c
> index d7dbbd469b89..acd137dd0957 100644
> --- a/drivers/mtd/nand/raw/nand_base.c
> +++ b/drivers/mtd/nand/raw/nand_base.c
> @@ -6301,6 +6301,7 @@ static const struct nand_ops rawnand_ops = {
>  static int nand_scan_tail(struct nand_chip *chip)
>  {
>  	struct mtd_info *mtd = nand_to_mtd(chip);
> +	struct nand_device *base = &chip->base;
>  	struct nand_ecc_ctrl *ecc = &chip->ecc;
>  	int ret, i;
>  
> @@ -6445,9 +6446,13 @@ static int nand_scan_tail(struct nand_chip *chip)
>  	if (!ecc->write_oob_raw)
>  		ecc->write_oob_raw = ecc->write_oob;
>  
> -	/* propagate ecc info to mtd_info */
> +	/* Propagate ECC info to the generic NAND and MTD layers */
>  	mtd->ecc_strength = ecc->strength;
> +	if (!base->ecc.ctx.conf.strength)
> +		base->ecc.ctx.conf.strength = ecc->strength;
>  	mtd->ecc_step_size = ecc->size;
> +	if (!base->ecc.ctx.conf.step_size)
> +		base->ecc.ctx.conf.step_size = ecc->size;
>  
>  	/*
>  	 * Set the number of read / write steps for one page depending on ECC
> @@ -6455,6 +6460,8 @@ static int nand_scan_tail(struct nand_chip *chip)
>  	 */
>  	if (!ecc->steps)
>  		ecc->steps = mtd->writesize / ecc->size;
> +	if (!base->ecc.ctx.nsteps)
> +		base->ecc.ctx.nsteps = ecc->steps;
>  	if (ecc->steps * ecc->size != mtd->writesize) {
>  		WARN(1, "Invalid ECC parameters\n");
>  		ret = -EINVAL;
> -- 
> 2.40.1
> 
> 

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