Re: [PATCH v2 2/2] ARM: dts: stm32: Enable MIPI DSI display support.

[Hua Dillon <dillonhua@xxxxxxxxx>]

Hi, Adrian,

Just one suggestion for you.

Adrian Pop <pop.adrian61@xxxxxxxxx> 于2020年7月3日周五 上午1:30写道：
>
> STM32f769-disco features a 4" MIPI DSI display: add support for it.
> On Cortex-M7 DMA can't use cached memory. For this reason I use a dedicated
> memory pool for DMA with no-cache attribute which is located at the end of
>  RAM.
>
> Signed-off-by: Adrian Pop <pop.adrian61@xxxxxxxxx>
> ---
>  arch/arm/boot/dts/stm32f746.dtsi      | 34 +++++++++++++++++++
>  arch/arm/boot/dts/stm32f769-disco.dts | 49 +++++++++++++++++++++++++++
>  2 files changed, 83 insertions(+)
>
> diff --git a/arch/arm/boot/dts/stm32f746.dtsi b/arch/arm/boot/dts/stm32f746.dtsi
> index 93c063796780..577a812ca01c 100644
> --- a/arch/arm/boot/dts/stm32f746.dtsi
> +++ b/arch/arm/boot/dts/stm32f746.dtsi
> @@ -48,6 +48,19 @@ / {
>         #address-cells = <1>;
>         #size-cells = <1>;
>
> +       reserved-memory {
> +               #address-cells = <1>;
> +               #size-cells = <1>;
> +               ranges;
> +
> +               linux,dma {
> +                       compatible = "shared-dma-pool";
> +                       linux,dma-default;
> +                       no-map;
> +                       reg = <0xc0f00000 0x100000>;
> +               };
> +       };
> +
Christoph Hellwig was submit a patch for !CONFIG_MMU platforms to support mmap.
the patch is : 1fbf57d05302 dma-direct: re-enable mmap for !CONFIG_MMU
i thought there is no need to create a reserved-memory for it.

>         clocks {
>                 clk_hse: clk-hse {
>                         #clock-cells = <0>;
> @@ -75,6 +88,27 @@ clk_i2s_ckin: clk-i2s-ckin {
>         };
>
>         soc {
> +               ltdc: display-controller@40016800 {
> +                       compatible = "st,stm32-ltdc";
> +                       reg = <0x40016800 0x200>;
> +                       interrupts = <88>, <89>;
> +                       resets = <&rcc STM32F7_APB2_RESET(LTDC)>;
> +                       clocks = <&rcc 1 CLK_LCD>;
> +                       clock-names = "lcd";
> +                       status = "disabled";
> +               };
> +
> +               dsi: dsi@40016c00 {
> +                       compatible = "st,stm32-dsi";
> +                       reg = <0x40016c00 0x800>;
> +                       interrupts = <98>;
> +                       clocks = <&rcc 1 CLK_F769_DSI>, <&clk_hse>;
> +                       clock-names = "pclk", "ref";
> +                       resets = <&rcc STM32F7_APB2_RESET(DSI)>;
> +                       reset-names = "apb";
> +                       status = "disabled";
> +               };
> +
>                 timer2: timer@40000000 {
>                         compatible = "st,stm32-timer";
>                         reg = <0x40000000 0x400>;
> diff --git a/arch/arm/boot/dts/stm32f769-disco.dts b/arch/arm/boot/dts/stm32f769-disco.dts
> index 1626e00bb2cb..a9e81b49809c 100644
> --- a/arch/arm/boot/dts/stm32f769-disco.dts
> +++ b/arch/arm/boot/dts/stm32f769-disco.dts
> @@ -153,3 +153,52 @@ &usbotg_hs {
>         pinctrl-names = "default";
>         status = "okay";
>  };
> +
> +&dsi {
> +       #address-cells = <1>;
> +       #size-cells = <0>;
> +       status = "okay";
> +
> +       ports {
> +               #address-cells = <1>;
> +               #size-cells = <0>;
> +
> +               port@0 {
> +                       reg = <0>;
> +                       dsi_in: endpoint {
> +                               remote-endpoint = <&ltdc_out_dsi>;
> +                       };
> +               };
> +
> +               port@1 {
> +                       reg = <1>;
> +                       dsi_out: endpoint {
> +                               remote-endpoint = <&dsi_in_panel>;
> +                       };
> +               };
> +
> +       };
> +
> +       panel: panel {
> +               compatible = "orisetech,otm8009a";
> +               reg = <0>;
> +               reset-gpios = <&gpioj 15 GPIO_ACTIVE_LOW>;
> +               status = "okay";
> +
> +               port {
> +                       dsi_in_panel: endpoint {
> +                               remote-endpoint = <&dsi_out>;
> +                       };
> +               };
> +       };
> +};
> +
> +&ltdc {
> +       status = "okay";
> +
> +       port {
> +               ltdc_out_dsi: endpoint {
> +                       remote-endpoint = <&dsi_in>;
> +               };
> +       };
> +};
> --
> 2.27.0
>
>
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