On Fri, Dec 18, 2020 at 06:50:05PM +0100, Guido Günther wrote:
> This makes sure the clock tree setup for the dphy is not dependent on
> other components.
>
> Without this change bringing up the display can fail like
>
> kernel: phy phy-30a00300.dphy.2: Invalid CM/CN/CO values: 165/217/1
> kernel: phy phy-30a00300.dphy.2: for hs_clk/ref_clk=451656000/593999998 ~ 165/217
>
> if LCDIF doesn't set up that part of the clock tree first. This was
> noticed when testing the Librem 5 devkit with defconfig. It doesn't
> happen when modules are built in.
>
> Signed-off-by: Guido Günther <agx@xxxxxxxxxxx>
> ---
> arch/arm64/boot/dts/freescale/imx8mq.dtsi | 11 ++++++++---
> 1 file changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/arch/arm64/boot/dts/freescale/imx8mq.dtsi b/arch/arm64/boot/dts/freescale/imx8mq.dtsi
> index a841a023e8e0..ca0847e8f13c 100644
> --- a/arch/arm64/boot/dts/freescale/imx8mq.dtsi
> +++ b/arch/arm64/boot/dts/freescale/imx8mq.dtsi
> @@ -1016,9 +1016,14 @@ dphy: dphy@30a00300 {
> reg = <0x30a00300 0x100>;
> clocks = <&clk IMX8MQ_CLK_DSI_PHY_REF>;
> clock-names = "phy_ref";
> - assigned-clocks = <&clk IMX8MQ_CLK_DSI_PHY_REF>;
> - assigned-clock-parents = <&clk IMX8MQ_VIDEO_PLL1_OUT>;
> - assigned-clock-rates = <24000000>;
> + assigned-clocks = <&clk IMX8MQ_VIDEO_PLL1_REF_SEL>,
> + <&clk IMX8MQ_VIDEO_PLL1_BYPASS>,
> + <&clk IMX8MQ_CLK_DSI_PHY_REF>,
> + <&clk IMX8MQ_VIDEO_PLL1>;
You do not seem to set parent or rate on IMX8MQ_VIDEO_PLL1. Why do you
have it here?
Shawn
> + assigned-clock-parents = <&clk IMX8MQ_CLK_25M>,
> + <&clk IMX8MQ_VIDEO_PLL1>,
> + <&clk IMX8MQ_VIDEO_PLL1_OUT>;
> + assigned-clock-rates = <0>, <0>, <24000000>;
> #phy-cells = <0>;
> power-domains = <&pgc_mipi>;
> status = "disabled";
> --
> 2.29.2
>
