Re: [PATCH 02/13] arm64: dts: imx8mp: re-parent IMX8MP_CLK_MEDIA_MIPI_PHY1_REF

[Adam Ford]

On Sun, Sep 17, 2023 at 5:40 PM Benjamin Bara <bbara93@xxxxxxxxx> wrote:
>
> From: Benjamin Bara <benjamin.bara@xxxxxxxxxxx>
>
> Similar to commit 07bb2e368820 ("arm64: dts: imx8mp: Fix video clock
> parents") the parent of IMX8MP_CLK_MEDIA_MIPI_PHY1_REF should be set in
> the media_blk_ctrl. Currently, if mipi_dsi is not in use, its parent is
> set to IMX8MP_VIDEO_PLL1_OUT, and might therefore clash with the
> constraints coming from a panel.

>From what I can see, it looks like the IMX8MP_CLK_MEDIA_MIPI_PHY1_REF
parent is being set to IMX8MP_CLK_24M.  Isn't that the default? I also
don't think we need to set a 24MHz clock to 24MHz if that's the
default.

If that is the case, I would suggest we try to remove the assignment
altogether to make the device tree simpler and less to untangle if a
board needs to manually manipulate the clocks for some specific
reason.

adam

>
> Cc: Adam Ford <aford173@xxxxxxxxx>
> Signed-off-by: Benjamin Bara <benjamin.bara@xxxxxxxxxxx>
> ---
>  arch/arm64/boot/dts/freescale/imx8mp.dtsi | 14 ++++++--------
>  1 file changed, 6 insertions(+), 8 deletions(-)
>
> diff --git a/arch/arm64/boot/dts/freescale/imx8mp.dtsi b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> index c946749a3d73..9539d747e28e 100644
> --- a/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> +++ b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> @@ -1640,11 +1640,6 @@ mipi_dsi: dsi@32e60000 {
>                                 clocks = <&clk IMX8MP_CLK_MEDIA_APB_ROOT>,
>                                          <&clk IMX8MP_CLK_MEDIA_MIPI_PHY1_REF>;
>                                 clock-names = "bus_clk", "sclk_mipi";
> -                               assigned-clocks = <&clk IMX8MP_CLK_MEDIA_APB>,
> -                                                 <&clk IMX8MP_CLK_MEDIA_MIPI_PHY1_REF>;
> -                               assigned-clock-parents = <&clk IMX8MP_SYS_PLL1_800M>,
> -                                                        <&clk IMX8MP_CLK_24M>;
> -                               assigned-clock-rates = <200000000>, <24000000>;
>                                 samsung,pll-clock-frequency = <24000000>;
>                                 interrupts = <GIC_SPI 18 IRQ_TYPE_LEVEL_HIGH>;
>                                 power-domains = <&media_blk_ctrl IMX8MP_MEDIABLK_PD_MIPI_DSI_1>;
> @@ -1747,13 +1742,16 @@ media_blk_ctrl: blk-ctrl@32ec0000 {
>                                                   <&clk IMX8MP_CLK_MEDIA_APB>,
>                                                   <&clk IMX8MP_CLK_MEDIA_DISP1_PIX>,
>                                                   <&clk IMX8MP_CLK_MEDIA_DISP2_PIX>,
> -                                                 <&clk IMX8MP_VIDEO_PLL1>;
> +                                                 <&clk IMX8MP_VIDEO_PLL1>,
> +                                                 <&clk IMX8MP_CLK_MEDIA_MIPI_PHY1_REF>;
>                                 assigned-clock-parents = <&clk IMX8MP_SYS_PLL2_1000M>,
>                                                          <&clk IMX8MP_SYS_PLL1_800M>,
>                                                          <&clk IMX8MP_VIDEO_PLL1_OUT>,
> -                                                        <&clk IMX8MP_VIDEO_PLL1_OUT>;
> +                                                        <&clk IMX8MP_VIDEO_PLL1_OUT>,
> +                                                        <&clk IMX8MP_CLK_24M>;
>                                 assigned-clock-rates = <500000000>, <200000000>,
> -                                                      <0>, <0>, <1039500000>;
> +                                                      <0>, <0>, <1039500000>,
> +                                                      <24000000>;
>                                 #power-domain-cells = <1>;
>
>                                 lvds_bridge: bridge@5c {
>
> --
> 2.34.1
>