[PATCH v6 21/21] mtd: spi-nor-core: Allow using Micron mt35xu512aba in Octal DTR mode

[Jagan Teki]

On Fri, Jun 5, 2020 at 6:16 PM Pratyush Yadav <p.yadav at ti.com> wrote:
>
> Since this flash doesn't have a Profile 1.0 table, the Octal DTR
> capabilities are enabled in the post SFDP fixup, along with the 8D-8D-8D
> fast read settings.
>
> Enable Octal DTR mode with 20 dummy cycles to allow running at the
> maximum supported frequency of 200Mhz.
>
> The flash supports the soft reset sequence. So, add the flag in the
> flash's info.
>
> Signed-off-by: Pratyush Yadav <p.yadav at ti.com>
> ---
>  drivers/mtd/spi/Kconfig        |  8 ++++
>  drivers/mtd/spi/spi-nor-core.c | 87 ++++++++++++++++++++++++++++++++++
>  drivers/mtd/spi/spi-nor-ids.c  |  4 +-
>  include/linux/mtd/spi-nor.h    | 10 +++-
>  4 files changed, 106 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/mtd/spi/Kconfig b/drivers/mtd/spi/Kconfig
> index ecfed6d215..9c549b39b7 100644
> --- a/drivers/mtd/spi/Kconfig
> +++ b/drivers/mtd/spi/Kconfig
> @@ -170,6 +170,14 @@ config SPI_FLASH_STMICRO
>         help
>           Add support for various STMicro SPI flash chips (M25Pxxx and N25Qxxx)
>
> +config SPI_FLASH_MT35XU
> +       bool "Micron MT35XU chip support"
> +       depends on SPI_FLASH_STMICRO
> +       help
> +        Add support for the Micron MT35XU chip. This is a separate config
> +        because the fixup hooks for this flash add extra size overhead. Boards
> +        that don't use the flash can disable this to save space.

This one and 20/21 are introducing the Kconfig options for single type
flashes in the micron family, does other effect size issues if dtr
make it available for STMICRO chips? if so, having a flash option of
dtr would much better and I hope Linux does it similarly.

Jagan.