[PATCH v2 6/6] arm64: allwinner: a64: Increase the MMC max frequency

Chen-Yu Tsai wens at csie.org
Mon Jan 9 09:01:20 PST 2017


On Tue, Jan 10, 2017 at 12:46 AM, Maxime Ripard
<maxime.ripard at free-electrons.com> wrote:
> All the controllers can have a maximum frequency of 200MHz.
>
> Since older SoCs cannot go that high, we cannot change the default maximum
> frequency, but fortunately for us we have a property for that in the DT.
>
> This also has the side effect of allowing to use the MMC HS200 mode for the
> boards that support it (with either 1.2v or 1.8v IOs).
>
> Signed-off-by: Maxime Ripard <maxime.ripard at free-electrons.com>
> ---
>  arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi | 3 +++
>  1 file changed, 3 insertions(+), 0 deletions(-)
>
> diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
> index 8e149498e096..f46ae965cf5b 100644
> --- a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
> +++ b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
> @@ -332,6 +332,7 @@
>                         resets = <&ccu RST_BUS_MMC0>;
>                         reset-names = "ahb";
>                         interrupts = <GIC_SPI 60 IRQ_TYPE_LEVEL_HIGH>;
> +                       max-frequency = <200000000>;

You also have to set one of MMC_CAP2_HS200* in the driver,
or mmc-hs200-1_8v or mmc-hs200-1_2v in the device tree to
actually use HS200, right?

ChenYu

>                         status = "disabled";
>                         #address-cells = <1>;
>                         #size-cells = <0>;
> @@ -345,6 +346,7 @@
>                         resets = <&ccu RST_BUS_MMC1>;
>                         reset-names = "ahb";
>                         interrupts = <GIC_SPI 61 IRQ_TYPE_LEVEL_HIGH>;
> +                       max-frequency = <200000000>;
>                         status = "disabled";
>                         #address-cells = <1>;
>                         #size-cells = <0>;
> @@ -358,6 +360,7 @@
>                         resets = <&ccu RST_BUS_MMC2>;
>                         reset-names = "ahb";
>                         interrupts = <GIC_SPI 62 IRQ_TYPE_LEVEL_HIGH>;
> +                       max-frequency = <200000000>;
>                         status = "disabled";
>                         #address-cells = <1>;
>                         #size-cells = <0>;
> --
> git-series 0.8.11



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