Re: [PATCH v1 2/5] mtd: nand: raw: rockchip-nand-controller: add skipbbt option

Miquel Raynal
2023-06-09T08:44:54Z

Hi Johan,

jbx6244@gmail.com wrote on Thu, 8 Jun 2023 18:30:27 +0200:

> On Rockchip SoCs the first boot stages are written on NAND
> with help of manufacturer software that uses a different format
> then the MTD framework. Skip the automatic BBT scan with the
> NAND_SKIP_BBTSCAN option so we can run it manually.

How do you run it manually?

> The NAND_NO_BBM_QUIRK option allows us to erase bad blocks with
> the nand_erase_nand() function and the flash_erase command.

For erasure you now have access to a debugfs entry for
experts/forensics which allows you to bypass all bad block checks.

>
> Signed-off-by: Johan Jonker <jbx6244@gmail.com>
> ---
> drivers/mtd/nand/raw/rockchip-nand-controller.c | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/drivers/mtd/nand/raw/rockchip-nand-controller.c b/drivers/mtd/nand/raw/rockchip-nand-controller.c
> index cafccc324..f56430f6c 100644
> --- a/drivers/mtd/nand/raw/rockchip-nand-controller.c
> +++ b/drivers/mtd/nand/raw/rockchip-nand-controller.c
> @@ -188,6 +188,10 @@ struct rk_nfc {
> unsigned long assigned_cs;
> };
>
> +static int skipbbt;
> +module_param(skipbbt, int, 0644);
> +MODULE_PARM_DESC(skipbbt, "Skip BBT scan if the NAND chip contains data not in MTD format.");

I highly dislike this.

It's not a module parameter that you need, it is related to a partition.

> +
> static inline struct rk_nfc_nand_chip *rk_nfc_to_rknand(struct nand_chip *chip)
> {
> return container_of(chip, struct rk_nfc_nand_chip, chip);
> @@ -1156,6 +1160,10 @@ static int rk_nfc_nand_chip_init(struct device *dev, struct rk_nfc *nfc,
>
> nand_set_controller_data(chip, nfc);
>
> + /* Skip the automatic BBT scan so we can run it manually. */
> + if (skipbbt)
> + chip->options |= NAND_SKIP_BBTSCAN | NAND_NO_BBM_QUIRK;
> +
> chip->options |= NAND_USES_DMA | NAND_NO_SUBPAGE_WRITE;
> chip->bbt_options = NAND_BBT_USE_FLASH | NAND_BBT_NO_OOB;
>
> --
> 2.30.2
>

Thanks,
Miquèl