Re: [PATCH 08/13] mtd: spinand: Reject 8D-8D-8D op_templates if octal_dtr_enale() is missing in manufacturer_op

From: Miquel Raynal
Date: Fri Aug 06 2021 - 15:01:52 EST


Hi Apurva,

Apurva Nandan <a-nandan@xxxxxx> wrote on Tue, 13 Jul 2021 13:05:33
+0000:

> The SPI NAND core doesn't know how to switch the flash to Octal DTR
> mode (i.e. which operations to perform). If the manufacturer hasn't
> implemented the octal_dtr_enable() manufacturer_op, the SPI NAND core
> wouldn't be able to switch to 8D-8D-8D mode and will also not be able
> to run in 1S-1S-1S mode due to already selected 8D-8D-8D read/write
> cache op_templates.
>
> So, avoid choosing a Octal DTR SPI op_template for read_cache,
> write_cache and update_cache operations, if the manufacturer_op
> octal_dtr_enable() is missing.

After looking at your previous commit I don't see why this patch would
be needed. octal_dtr_enable() only updates the mode when it succeeds so
I don't think this patch is really needed.

>
> Signed-off-by: Apurva Nandan <a-nandan@xxxxxx>
> ---
> drivers/mtd/nand/spi/core.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mtd/nand/spi/core.c b/drivers/mtd/nand/spi/core.c
> index 19d8affac058..8711e887b795 100644
> --- a/drivers/mtd/nand/spi/core.c
> +++ b/drivers/mtd/nand/spi/core.c
> @@ -1028,6 +1028,8 @@ static int spinand_manufacturer_match(struct spinand_device *spinand,
> if (id[0] != manufacturer->id)
> continue;
>
> + spinand->manufacturer = manufacturer;
> +
> ret = spinand_match_and_init(spinand,
> manufacturer->chips,
> manufacturer->nchips,
> @@ -1035,7 +1037,6 @@ static int spinand_manufacturer_match(struct spinand_device *spinand,
> if (ret < 0)
> continue;
>
> - spinand->manufacturer = manufacturer;
> return 0;
> }
> return -ENOTSUPP;
> @@ -1097,6 +1098,10 @@ spinand_select_op_variant(struct spinand_device *spinand,
> unsigned int nbytes;
> int ret;
>
> + if (spinand_op_is_octal_dtr(&op) &&
> + !spinand->manufacturer->ops->octal_dtr_enable)
> + continue;
> +
> nbytes = nanddev_per_page_oobsize(nand) +
> nanddev_page_size(nand);
>

Thanks,
Miquèl