Re: [PATCH v3] arm64: dts: mt8173: add mmsel clocks for 4K support

From: Philipp Zabel
Date: Wed Jul 27 2016 - 05:32:57 EST


Am Mittwoch, den 27.07.2016, 16:25 +0800 schrieb Bibby Hsieh:
> If MT8173 can support HDMI 4K resoultion, the
> VENCPLL should be configured to 800MHZ.
> We didn't set VENCPLL directly, we set the
> mm_sel to 400MHz statically in the board device tree.

Maybe add a comment that the board .dts file should override the clock
rate property with the higher VENCPLL frequency the board supports HDMI
4K resolution.

> Signed-off-by: Bibby Hsieh <bibby.hsieh@xxxxxxxxxxxx>
> ---
> Changes since v2:
> - Align the clocks of dpi0 node.
>
> Changes since v1:
> - Do not set the VENCPLL by clk_set_rate
> at display driver.
> - Configure the mm_sel to 400MHz statically
> in the board device tree.
> ---
> arch/arm64/boot/dts/mediatek/mt8173.dtsi | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/arch/arm64/boot/dts/mediatek/mt8173.dtsi b/arch/arm64/boot/dts/mediatek/mt8173.dtsi
> index 78529e4..9c22204 100644
> --- a/arch/arm64/boot/dts/mediatek/mt8173.dtsi
> +++ b/arch/arm64/boot/dts/mediatek/mt8173.dtsi
> @@ -690,7 +690,9 @@
> compatible = "mediatek,mt8173-mmsys", "syscon";
> reg = <0 0x14000000 0 0x1000>;
> power-domains = <&scpsys MT8173_POWER_DOMAIN_MM>;
> + clocks = <&topckgen CLK_TOP_MM_SEL>;
> #clock-cells = <1>;
> + clock-frequency = <400000000>;

According to the "Assigned clock parents and rates" section in
Documentation/devicetree/bindings/clock/clock-bindings.txt,
this should be:
assigned-clocks = <&topckgen CLK_TOP_MM_SEL>;
assigned-clock-rates = <400000000>;

regards
Philipp