Re: [PATCH 5/8] arm64: dts: imx8mm-kontron: Fix CAN SPI clock frequency

From: Shawn Guo
Date: Tue Oct 05 2021 - 03:12:39 EST


On Thu, Sep 30, 2021 at 05:56:28PM +0200, Frieder Schrempf wrote:
> From: Frieder Schrempf <frieder.schrempf@xxxxxxxxxx>
>
> The MCP2515 can be used with an SPI clock of up to 10 MHz. Set the
> limit accordingly to prevent any performance issues caused by the
> really low clock speed of 100 kHz.

Could you share some testing result of this change?

>
> Fixes: 21c4f45b335f ("arm64: dts: Add the Kontron i.MX8M Mini SoMs and baseboards")

It's really an optimization rather than fix, isn't it?

Shawn

> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Frieder Schrempf <frieder.schrempf@xxxxxxxxxx>
> ---
> arch/arm64/boot/dts/freescale/imx8mm-kontron-n801x-s.dts | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/arm64/boot/dts/freescale/imx8mm-kontron-n801x-s.dts b/arch/arm64/boot/dts/freescale/imx8mm-kontron-n801x-s.dts
> index f2c8ccefd1bf..dbf11e03ecce 100644
> --- a/arch/arm64/boot/dts/freescale/imx8mm-kontron-n801x-s.dts
> +++ b/arch/arm64/boot/dts/freescale/imx8mm-kontron-n801x-s.dts
> @@ -98,7 +98,7 @@ can0: can@0 {
> clocks = <&osc_can>;
> interrupt-parent = <&gpio4>;
> interrupts = <28 IRQ_TYPE_EDGE_FALLING>;
> - spi-max-frequency = <100000>;
> + spi-max-frequency = <10000000>;
> vdd-supply = <&reg_vdd_3v3>;
> xceiver-supply = <&reg_vdd_5v>;
> };
> --
> 2.33.0
>