[PATCH RESEND] mtd: nand: allow NAND_NO_SUBPAGE_WRITE to be set from driver

[Matthieu CASTET]

Hi,

for ONFI flash (like this micron one) the information should be extracted form
the ONFI table (programs_per_page IIRC)

This should be better than relying on the SOC driver for setting this flags.

Does the gpmi driver set this flag because it do not support partial write ?
In this case why it doesn't set  chip->ecc.steps to 1 ?

Matthieu


Brian Norris a écrit :
> The NAND_CHIPOPTIONS_MSK has limited utility and is causing real bugs. It
> silently masks off at least one flag that might be set by the driver
> (NAND_NO_SUBPAGE_WRITE). This breaks the GPMI NAND driver and possibly others.
> 
> Really, as long as driver writers exercise a small amount of care with NAND_*
> options, this mask is not necessary at all. Thus, kill it.
> 
>>From Huang Shijie:
> 
> "I tested this patch on imx6q-arm2 board with Micron MT29F32G08QAA.
> it works fine, thanks."
> 
> Signed-off-by: Brian Norris <computersforpeace at gmail.com>
> Tested-by: Huang Shijie <shijie8 at gmail.com>
> Cc: Marek Vasut <marex at denx.de>
> ---
> Hello Artem/David,
> 
> GPMI NAND has needed this patch for some time, and I think it was agreed
> on by a few. I'm resending to get acknowledgment from a maintainer.
> 
>  drivers/mtd/nand/nand_base.c | 7 ++-----
>  include/linux/mtd/nand.h     | 3 ---
>  2 files changed, 2 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
> index ead301a..996cc48 100644
> --- a/drivers/mtd/nand/nand_base.c
> +++ b/drivers/mtd/nand/nand_base.c
> @@ -2909,8 +2909,6 @@ static int nand_flash_detect_onfi(struct mtd_info *mtd, struct nand_chip *chip,
>  	if (le16_to_cpu(p->features) & 1)
>  		*busw = NAND_BUSWIDTH_16;
>  
> -	chip->options &= ~NAND_CHIPOPTIONS_MSK;
> -
>  	pr_info("ONFI flash detected\n");
>  	return 1;
>  }
> @@ -3074,9 +3072,8 @@ static struct nand_flash_dev *nand_get_flash_type(struct mtd_info *mtd,
>  			mtd->erasesize <<= ((id_data[3] & 0x03) << 1);
>  		}
>  	}
> -	/* Get chip options, preserve non chip based options */
> -	chip->options &= ~NAND_CHIPOPTIONS_MSK;
> -	chip->options |= type->options & NAND_CHIPOPTIONS_MSK;
> +	/* Get chip options */
> +	chip->options |= type->options;
>  
>  	/*
>  	 * Check if chip is not a Samsung device. Do not clear the
> diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
> index 6dce5a7..eeb7015 100644
> --- a/include/linux/mtd/nand.h
> +++ b/include/linux/mtd/nand.h
> @@ -206,9 +206,6 @@ typedef enum {
>  #define NAND_SUBPAGE_READ(chip) ((chip->ecc.mode == NAND_ECC_SOFT) \
>  					&& (chip->page_shift > 9))
>  
> -/* Mask to zero out the chip options, which come from the id table */
> -#define NAND_CHIPOPTIONS_MSK	0x0000ffff
> -
>  /* Non chip related options */
>  /* This option skips the bbt scan during initialization. */
>  #define NAND_SKIP_BBTSCAN	0x00010000