Re: [PATCH] arm64: dts: imx8mm: Add CSI nodes

[Adam Ford]

On Wed, Oct 13, 2021 at 9:52 PM Adam Ford <aford173@xxxxxxxxx> wrote:
>
> There is a csi bridge and csis interface that tie together
> to allow csi2 capture.
>
> Signed-off-by: Adam Ford <aford173@xxxxxxxxx>

Laurent,

Since you did some work to make the csis functional on the imx8mm, I
was hoping you might have some insights.  Please see below:

>
> diff --git a/arch/arm64/boot/dts/freescale/imx8mm.dtsi b/arch/arm64/boot/dts/freescale/imx8mm.dtsi
> index c2f3f118f82e..8a8a5d0a4a1e 100644
> --- a/arch/arm64/boot/dts/freescale/imx8mm.dtsi
> +++ b/arch/arm64/boot/dts/freescale/imx8mm.dtsi
> @@ -1068,6 +1068,22 @@ aips4: bus@32c00000 {
>                         #size-cells = <1>;
>                         ranges = <0x32c00000 0x32c00000 0x400000>;
>
> +                       csi: csi@32e20000 {
> +                               compatible = "fsl,imx7-csi";
> +                               reg = <0x32e20000 0x1000>;
> +                               interrupts = <GIC_SPI 16 IRQ_TYPE_LEVEL_HIGH>;
> +                               clocks = <&clk IMX8MM_CLK_CSI1_ROOT>;
> +                               clock-names = "mclk";
> +                               power-domains = <&disp_blk_ctrl IMX8MM_DISPBLK_PD_CSI_BRIDGE>;
> +                               status = "disabled";
> +
> +                               port {
> +                                       csi_in: endpoint {
> +                                               remote-endpoint = <&imx8mm_mipi_csi_out>;
> +                                       };
> +                               };
> +                       };
> +
>                         disp_blk_ctrl: blk-ctrl@32e28000 {
>                                 compatible = "fsl,imx8mm-disp-blk-ctrl", "syscon";
>                                 reg = <0x32e28000 0x100>;
> @@ -1095,6 +1111,41 @@ disp_blk_ctrl: blk-ctrl@32e28000 {
>                                 #power-domain-cells = <1>;
>                         };
>
> +                       mipi_csi2: mipi-csi@32e30000 {
> +                               compatible = "fsl,imx8mm-mipi-csi2";
> +                               reg = <0x32e30000 0x1000>;
> +                               interrupts = <GIC_SPI 17 IRQ_TYPE_LEVEL_HIGH>;
> +                               clock-frequency = <333000000>;
> +                               clocks = <&clk IMX8MM_CLK_DISP_APB_ROOT>,
> +                                        <&clk IMX8MM_CLK_CSI1_ROOT>,
> +                                        <&clk IMX8MM_CLK_CSI1_PHY_REF>,
> +                                        <&clk IMX8MM_CLK_DISP_AXI_ROOT>;

When comparing clock parents and the clock rates to one of NXP's
kernels, it appears we need assigned-clocks and assigned-clock-parents
to allow the CSI1 clocks to run fast enough.

assigned-clocks = <&clk IMX8MM_CLK_CSI1_PHY_REF>,
  <&clk IMX8MM_CLK_CSI1_CORE>,
  <&clk IMX8MM_CLK_CSI1_ROOT>,
  <&clk IMX8MM_CLK_CSI1_ESC>;
assigned-clock-parents = <&clk IMX8MM_SYS_PLL2_1000M>,
  <&clk IMX8MM_SYS_PLL2_1000M>,
  <&clk IMX8MM_CLK_CSI1_CORE>,
  <&clk IMX8MM_SYS_PLL1_800M>;

However, even with this, I am attempting to capture.  While I can get
the pipeline enabled, when I try to capture a file, I get no data.  i
can use control-c to exit gstreamer, so I know the kernel didn't hang.
I don't get errors, but I don't get data either.

Any ideas if what/if any other clock entries might be missing?


> +                               clock-names = "pclk", "wrap", "phy", "axi";
> +                               power-domains = <&disp_blk_ctrl IMX8MM_DISPBLK_PD_MIPI_CSI>;
> +                               status = "disabled";
> +
> +                               ports {
> +                                       #address-cells = <1>;
> +                                       #size-cells = <0>;
> +
> +                                       port@0 {
> +                                               reg = <0>;
> +
> +                                               imx8mm_mipi_csi_in: endpoint {
> +                                               };
> +                                       };
> +
> +                                       port@1 {
> +                                               reg = <1>;
> +
> +                                               imx8mm_mipi_csi_out: endpoint {
> +                                                       remote-endpoint = <&csi_in>;
> +                                               };
> +                                       };
> +                               };
> +                       };
> +
> +
>                         usbotg1: usb@32e40000 {
>                                 compatible = "fsl,imx8mm-usb", "fsl,imx7d-usb";
>                                 reg = <0x32e40000 0x200>;
> --
> 2.25.1
>