Re: [PATCH 4/4] arm64: dts: lx2160a: update fspi node

Boris Brezillon
2018-10-04T09:18:22Z

On Thu, 4 Oct 2018 14:18:40 +0530
Yogesh Gaur <yogeshnarayan.gaur@nxp.com> wrote:

> Flash mt35xu512aba connected to FlexSPI controller supports
> 1-1-8 protocol.
> Added flag spi-rx-bus-width and spi-tx-bus-width with values as
> 8 and 1 respectively for both flashes connected at CS0 and CS1.
>
> Signed-off-by: Yogesh Gaur <yogeshnarayan.gaur@nxp.com>
> ---
> arch/arm64/boot/dts/freescale/fsl-lx2160a-rdb.dts | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/arch/arm64/boot/dts/freescale/fsl-lx2160a-rdb.dts b/arch/arm64/boot/dts/freescale/fsl-lx2160a-rdb.dts
> index 901ca346..817175a 100644
> --- a/arch/arm64/boot/dts/freescale/fsl-lx2160a-rdb.dts
> +++ b/arch/arm64/boot/dts/freescale/fsl-lx2160a-rdb.dts
> @@ -42,6 +42,8 @@
> m25p,fast-read;
> spi-max-frequency = <20000000>;
> reg = <0>;
> + spi-rx-bus-width = <8>;
> + spi-tx-bus-width = <1>;

Why 1? The flash is already flagged with SPI_NOR_OCTAL_READ, which
means only the read path will use 1-1-8 mode, so you can safely set
spi-tx-bus-width here and let the framework choose the appropriate mode
based on the flash capabilities.

> };
>
> mt35xu512aba1: flash@1 {
> @@ -51,6 +53,8 @@
> m25p,fast-read;
> spi-max-frequency = <20000000>;
> reg = <1>;
> + spi-rx-bus-width = <8>;
> + spi-tx-bus-width = <1>;
> };
> };
>