Re: [PATCH 3/3] mtd: spi-nor: Add USE_FSR flag for n25q* entries

From: Vignesh Raghavendra
Date: Thu Dec 12 2019 - 02:32:17 EST


Hi Tudor,

On 10/12/19 10:11 pm, Tudor.Ambarus@xxxxxxxxxxxxx wrote:
> Hi, Vignesh,
>
> On 12/5/19 8:59 AM, Vignesh Raghavendra wrote:
>> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
>>
>> Add USE_FSR flag to all variants of n25q entries that support Flag Status
>> Register.
>
> On a first look, all Micron flashes define the Flag Status Register. Do you know
> if there are any Micron flash that don't support FSR? If not, would you be
> interested in doing some documentation work to check this?
>

n25q and mt25 series support FSR but older m25p/m45p parts don't have
FSR. I don't know any easy way of finding out if flash part is m25p type.

> I think we can do this more generic, always set SNOR_F_USE_FSR for micron
> flashes, like below. More, if FSR is specific just for Micron, we can get rid of
> the USE_FSR flag too.
>

AFAIK, FSR is definitely Micron specific (other flash vendors have
different registers/bits providing similar information though).


> Thanks, Vignesh.
>
> diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
> index f4afe123e9dc..fe10beea60c3 100644
> --- a/drivers/mtd/spi-nor/spi-nor.c
> +++ b/drivers/mtd/spi-nor/spi-nor.c
> @@ -4595,7 +4595,7 @@ static void sst_set_default_init(struct spi_nor *nor)
>
> static void st_micron_set_default_init(struct spi_nor *nor)
> {
> - nor->flags |= SNOR_F_HAS_LOCK;
> + nor->flags |= SNOR_F_HAS_LOCK | SNOR_F_USE_FSR;
> nor->params.quad_enable = NULL;
> nor->params.set_4byte = st_micron_set_4byte;
> }
>

--
Regards
Vignesh