Re: [RFC/patch 2/2] arm64: boot: dts: qcom: surface duo: add minimal framebuffer

From: Felipe Balbi
Date: Sat Dec 18 2021 - 02:34:36 EST



Hi,

Konrad Dybcio <konrad.dybcio@xxxxxxxxxxxxxx> writes:

> On 17.12.2021 13:57, Felipe Balbi wrote:
>> From: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxx>
>>
>> Add a minimal framebuffer device so we can use the display on the
>> Surface Duo device.
>>
>> Signed-off-by: Felipe Balbi <felipe.balbi@xxxxxxxxxxxxx>
>> ---
>> .../dts/qcom/sm8150-microsoft-surface-duo.dts | 19 +++++++++++++++++++
>> 1 file changed, 19 insertions(+)
>>
>> diff --git a/arch/arm64/boot/dts/qcom/sm8150-microsoft-surface-duo.dts b/arch/arm64/boot/dts/qcom/sm8150-microsoft-surface-duo.dts
>> index a73317e1a824..c629ec115fec 100644
>> --- a/arch/arm64/boot/dts/qcom/sm8150-microsoft-surface-duo.dts
>> +++ b/arch/arm64/boot/dts/qcom/sm8150-microsoft-surface-duo.dts
>> @@ -25,6 +25,17 @@ chosen {
>> stdout-path = "serial0:115200n8";
>> };
>>
>> + framebuffer0: framebuffer@9c000000 {
>> + compatible = "simple-framebuffer";
>> + reg = <0 0x9c000000 0 0x02400000>;
>
> You can remove the leading 0 in the size cell.

okay

>> + status = "okay";
>
> This line is unnecessary, as it's enabled by default

understood

>> @@ -472,6 +483,14 @@ &pon_resin {
>> linux,code = <KEY_VOLUMEDOWN>;
>> };
>>
>> +&reserved_memory {
>> + splash_region: splash_region@9c000000 {
>> + /* We expect the bootloader to fill in the size */
>
> Would it be different than the framebuffer size?

honestly, I used this mainly to get the correct base address and size. I
had 0 everywhere and bootloader filled the entire thing for me. I can
just hardcode with the expected values anyway.

--
balbi