Re: [PATCH v5 3/3] ARM: dts: stm32: support display on stm32f746-disco board

[Dario Binacchi <dario.binacchi@xxxxxxxxxxxxxxxxxxxx>]

Hi Alexandre,

On Tue, Jul 11, 2023 at 2:13 PM Alexandre TORGUE
<alexandre.torgue@xxxxxxxxxxx> wrote:
>
> Hi Dario
>
> On 6/29/23 10:37, Dario Binacchi wrote:
> > Add support to Rocktech RK043FN48H display on stm32f746-disco board.
> >
> > Signed-off-by: Dario Binacchi <dario.binacchi@xxxxxxxxxxxxxxxxxxxx>
> >
> > ---
> >
> > Changes in v5:
> > I am confident that framebuffer sizing is a real requirement for STM32 boards,
> > but I need some time to understand if and how to introduce this functionality.
> > Therefore, I drop the following patches to allow the series to be fully merged:
> >   - [4/6] dt-bindings: display: stm32-ltdc: add optional st,fb-bpp property
> >   - [5/6] ARM: dts: stm32: set framebuffer bit depth on stm32f746-disco
> >   - [6/6] drm/stm: set framebuffer bit depth through DTS property
> >
> > Changes in v4:
> > - Use DTS property instead of module parameter to set the framebuffer bit depth.
> >
> > Changes in v3:
> > - drop [4/6] dt-bindings: display: simple: add Rocktech RK043FN48H
> >    Applied to https://anongit.freedesktop.org/git/drm/drm-misc.git (drm-misc-next):
> >    https://cgit.freedesktop.org/drm/drm-misc/commit/?id=c42a37a27c777d63961dd634a30f7c887949491a
> > - drop [5/6] drm/panel: simple: add support for Rocktech RK043FN48H panel
> >    Applied to https://anongit.freedesktop.org/git/drm/drm-misc.git (drm-misc-next)
> >    https://cgit.freedesktop.org/drm/drm-misc/commit/?id=13cdd12a9f934158f4ec817cf048fcb4384aa9dc
> >
> >   arch/arm/boot/dts/stm32f746-disco.dts | 51 +++++++++++++++++++++++++++
> >   1 file changed, 51 insertions(+)
> >
> > diff --git a/arch/arm/boot/dts/stm32f746-disco.dts b/arch/arm/boot/dts/stm32f746-disco.dts
> > index c11616ed5fc6..cda423b6a874 100644
> > --- a/arch/arm/boot/dts/stm32f746-disco.dts
> > +++ b/arch/arm/boot/dts/stm32f746-disco.dts
> > @@ -60,10 +60,41 @@ memory@c0000000 {
> >               reg = <0xC0000000 0x800000>;
> >       };
> >
> > +     reserved-memory {
> > +             #address-cells = <1>;
> > +             #size-cells = <1>;
> > +             ranges;
> > +
> > +             linux,cma {
> > +                     compatible = "shared-dma-pool";
> > +                     no-map;
> > +                     size = <0x80000>;
> > +                     linux,dma-default;
> > +             };
> > +     };
> > +
> >       aliases {
> >               serial0 = &usart1;
> >       };
> >
> > +     backlight: backlight {
> > +             compatible = "gpio-backlight";
> > +             gpios = <&gpiok 3 GPIO_ACTIVE_HIGH>;
> > +             status = "okay";
> > +     };
> > +
> > +     panel_rgb: panel-rgb {
> > +             compatible = "rocktech,rk043fn48h";
> > +             backlight = <&backlight>;
> > +             enable-gpios = <&gpioi 12 GPIO_ACTIVE_HIGH>;
> > +             status = "okay";
> > +             port {
> > +                     panel_in_rgb: endpoint {
> > +                             remote-endpoint = <&ltdc_out_rgb>;
> > +                     };
> > +             };
> > +     };
> > +
> >       usbotg_hs_phy: usb-phy {
> >               #phy-cells = <0>;
> >               compatible = "usb-nop-xceiv";
> > @@ -99,6 +130,26 @@ &i2c1 {
> >       status = "okay";
> >   };
> >
> > +&dma1 {
> > +     status = "okay";
> > +};
> > +
> > +&dma2 {
> > +     status = "okay";
> >
> Why do you enable DMAs ? It seems not used by LTDC.

You're right, I'll send version 6 shortly with the removal of DMA.

Thanks and regards,
Dario

>
> > +&ltdc {
> > +     pinctrl-0 = <&ltdc_pins_a>;
> > +     pinctrl-names = "default";
> > +     status = "okay";
> > +
> > +     port {
> > +             ltdc_out_rgb: endpoint {
> > +                     remote-endpoint = <&panel_in_rgb>;
> > +             };
> > +     };
> > +};
> > +
> >   &sdio1 {
> >       status = "okay";
> >       vmmc-supply = <&mmc_vcard>;
>


-- 

Dario Binacchi

Senior Embedded Linux Developer

dario.binacchi@xxxxxxxxxxxxxxxxxxxx

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