Re: rk3399: Graphical artifacts when running for-next

[Robert Foss <robert.foss-ZGY8ohtN/8qB+jHODAdFcQ@public.gmane.org>]

Hey again,

I found the issue, and it has been solved by Ezequiel
before me.

A DDC I2C bus specifier is required for DDC EDID probing to work
properly.

https://www.spinics.net/lists/arm-kernel/msg708359.html

Thanks for participating in this goose-chase with me.


Rob.

On 2/22/19 9:41 AM, Robert Foss wrote:
> Hey Jonas,
> 
> On 2/21/19 9:29 PM, Jonas Karlman wrote:
>> On 2019-02-21 20:42, Robert Foss wrote:
>>>
>>> On 2/21/19 8:15 PM, Ezequiel Garcia wrote:
>>>> Folks,
>>>>
>>>> On Thu, 2019-02-21 at 20:08 +0100, Robert Foss wrote:
>>>> [..]
>>>>
>>>> The clock debugging is obviously good research.
>>>>
>>>>>>
>>>>>> Additionally I've had a look at the libdrm modetest util, and it is reporting
>>>>>> far fewer modes than what I would expect on my 4k monitor.
>>>>>>
>>>> That said, this is also worth looking into.
>>>> I'm curious, is the EDID the kernel getting OK?
>>>>
>>> Given that modetest lists way too few modes, I would think
>>> there could be some EDID related issues.
>>
>> It is more likely the issue is in dw_hdmi_rockchip_mode_valid(), it currently 
>> filters out
>> any mode not defined in rockchip_mpll_cfg.
>> That method needs some changes to allow for 4k modes and fractal refresh rates.
>> E.g. for RK3328 it should probably check the inno-hdmi-phy clock rates.
> 
> 
> This seemed like a good suggetions, so I disabled the rockchip_mpll_cfg in 
> dw_hdmi_rockchip_mode_valid(), and ran libdrm/modetest. I now have 5 modes.
> But no higher resolution ones, only low resolution ones that don't seem
> 
> $ modetest
> [..]
> trying to open device 'rockchip'...done
> Encoders:
> id      crtc    type    possible crtcs  possible clones
> 44      34      TMDS    0x00000003      0x00000000
> 
> Connectors:
> id      encoder status          name            size (mm)       modes   encoders
> 45      44      connected       HDMI-A-1        0x0             5       44
>    modes:
>          name refresh (Hz) hdisp hss hse htot vdisp vss vse vtot)
>    1024x768 60 1024 1048 1184 1344 768 771 777 806 65000 flags: [..]
>    800x600 60 800 840 968 1056 600 601 605 628 40000 flags: [..]
>    800x600 56 800 824 896 1024 600 601 603 625 36000 flags: [..]
>    848x480 60 848 864 976 1088 480 486 494 517 33750 flags: [..]
>    640x480 60 640 656 752 800 480 490 492 525 25175 flags: [...]