Re: [PATCH v1 2/3] ARM: dts: stm32: enable Vivante GPU support on stm32mp157c-ed1 board

From: Lucas Stach
Date: Fri Feb 15 2019 - 11:14:39 EST


Am Freitag, den 15.02.2019, 16:58 +0100 schrieb Pierre-Yves MORDRET:
> Enable Vivante GPU driver for stm32mp157c-ed1 board.
>
> Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mordret@xxxxxx>
> ---
> Âarch/arm/boot/dts/stm32mp157c-ed1.dts | 16 ++++++++++++++++
> Â1 file changed, 16 insertions(+)
>
> diff --git a/arch/arm/boot/dts/stm32mp157c-ed1.dts
> b/arch/arm/boot/dts/stm32mp157c-ed1.dts
> index 98ef7a0..792f402 100644
> --- a/arch/arm/boot/dts/stm32mp157c-ed1.dts
> +++ b/arch/arm/boot/dts/stm32mp157c-ed1.dts
> @@ -20,6 +20,17 @@
> Â reg = <0xC0000000 0x40000000>;
> Â };
> Â
> + reserved-memory {
> + #address-cells = <1>;
> + #size-cells = <1>;
> + ranges;
> +
> + gpu_reserved: gpu@f8000000 {
> + reg = <0xf8000000 0x8000000>;
> + no-map;
> + };
> + };
> +

I don't think you need this. The GPU driver uses very little contig dma
memory. Most of the GPU memory is ordinary paged memory, so setting
aside a private memory region of this size is a waste of memory. Most
likely you can just allow the GPU driver to use the system global CMA
region.

Regards,
Lucas


> Â aliases {
> Â serial0 = &uart4;
> Â };
> @@ -53,6 +64,11 @@
> Â status = "okay";
> Â};
> Â
> +&gpu {
> + contiguous-area = <&gpu_reserved>;
> + status = "okay";
> +};
> +
> Â&i2c4 {
> Â pinctrl-names = "default";
> Â pinctrl-0 = <&i2c4_pins_a>;