[PATCH v3 0/3] drm/rockchip: Add driver for the new DSI2 controller

[Andy Yan]

Hi,

At 2024-12-10 07:12:26, "Heiko Stübner" <heiko at sntech.de> wrote:
>Am Montag, 9. Dezember 2024, 17:11:03 CET schrieb Diederik de Haas:
>> Hi,
>> 
>> On Mon Dec 9, 2024 at 4:06 PM CET, Daniel Semkowicz wrote:
>> > On 03.12.24 21:54, Heiko Stuebner wrote:
>> > > This series adds a bridge and glue driver for the DSI2 controller found
>> > > in the rk3588 soc from Rockchip, that is based on a Synopsis IP block.
>> > > 
>> >
>> > I did more tests with different LVDS displays. I tested following
>> > configurations with DSI/LVDS bridge:
>> > - 1024x600 at 60.01
>> > - 1024x768 at 60.02
>> > - 1280x800 at 60.07
>> > - 1366x768 at 60.06
>> >
>> > All of them worked without issues, except 1366x768.
>> > With this resolution, video is blurry, and offset incorrectly
>> > to the left. There are also repeating errors on the console:
>> >
>> >   rockchip-drm display-subsystem: [drm] *ERROR* POST_BUF_EMPTY irq err at vp3
>> >
>> > In correct operation with other resolutions, there is no error.
>> > I am not sure if this is a problem in your series or rather in VOP2
>> > driver.
>
>This really sounds like something is wrong on the vop side.
>The interrupt is part of the vop, the divisable by 4 things likely too.

This is a hardware limitation on vop side:
The horizontal resolution must be 4 pixel aligned.



>
>
>Heiko
>
>
>> 
>> On my PineTab2 I got similar messages about 2 weeks ago:
>> rockchip-drm display-subsystem: [drm] *ERROR* POST_BUF_EMPTY irq err at vp1
>> 
>> Preceding those, I got several panfrost related errors:
>> 
>> panfrost fde60000.gpu: get clock failed -517
>> panfrost fde60000.gpu: clk init failed -517
>> platform fde60000.gpu: deferred probe pending: (reason unknown)
>> platform cpufreq-dt: deferred probe pending: (reason unknown)
>> vdd_gpu_npu: disabling
>> 
>> But can also be that the PineTab2 (likely) needs regulator-always-on
>> and regulator-boot-on in its vdd_gpu_npu node.
>> 
>> > I tried to track down the problem, and it seems to be a generic issue
>> > when horizontal line width is not divisible by 4.
>> > Lowering line width to 1364px fixes the issue, but of course I have two
>> > vertical lines of black pixels on the right.
>> > I also made some tests with 720x1280 DSI display. Lowering horizontal
>> > line to 718px shows the same problem. With 720px and 716px it works
>> > correctly.
>> 
>> I haven't look further into it, but the PT2 has a 1280x800 resolution.
>> 
>> HTH,
>>   Diederik
>> 
>
>
>