Dear James,
Am 11.04.22 um 23:39 schrieb James Dutton:
I have an Oculus Rift S, that I am trying to get working in Linux.
Please always mention the Linux kernel version.
I have an AMD Vega 56 graphics card.
The VR headset plugs into a display port of the Vega56.
The amdgpu driver sees the connection, and tries to process it.
The problem is it cannot process the EDID, so fails to recognise the
VR headset, and the VR headset does not work as a result.
Please find the EDID below.
I am guessing that the following is causing the problem:
Established Timings I & II: none
Standard Timings: none
Forcing the driver to understand the Detailed mode, to which it is failing.
If it helps, when attached to windows 10, it uses 1440x2560, portrait mode.
Some dmesg lines that may be useful:
// We should pick 1440x2560 as Windows picks that, but for some reason
is rejects it with error 10.
[10402.650734] [drm:create_validate_stream_for_sink [amdgpu]] Mode
1440x2560 (clk 571570) failed DC validation with error 10 (No DP link
bandwidth)
[10402.650991] [drm:update_stream_scaling_settings [amdgpu]]
Destination Rectangle x:0 y:0 width:1440 height:2560
[10402.651225] [drm:create_validate_stream_for_sink [amdgpu]] Mode
1440x2560 (clk 571570) failed DC validation with error 10 (No DP link
bandwidth)
(Please use an email program, which does not wrap lines after 72
characters.)
Can anyone help give me with some pointers as to how to get the amdgpu
driver to accept this EDID?
So, did you do any changes to Linux? Why do you think the EDID is at fault?
[…]
I suggest to analyze, why `No DP link bandwidth` is logged. The macro is
`DC_NO_DP_LINK_BANDWIDTH`, and you should first check why
`dp_validate_mode_timing()` in
`drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c` returns false.
Kind regards,
Paul
PS: Using the issue tracker [1] might make it easier to keep track of
this problem, and also to attach all the necessary information.
[1]: https://gitlab.freedesktop.org/drm/amd/-/issues/
