xrandr only finds one provider

[Michel Dänzer]

On 2019-03-22 4:04 p.m., Andriy Samsonyuk wrote:
> Hi,
> 
> i am having a weird xorg behavior i don't understand.
> Any help will be appreciated.
> 
> i am running freebsd-12
> xorg-server-1.18.4_11,1
> xrandr-1.5.0
> 
> on dell precision 7530
> This laptop has 2 GPUs:
> ***
> lspci -nn | grep -i vga
> 00:02.0 VGA compatible controller [0300]: Intel Corporation Device [8086:3e94]
> 01:00.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc. [AMD/ATI] Baffin [Radeon Pro WX 4130/4150] [1002:67e8]
> ***
> 
> Installed are:
> xf86-video-intel-2.99.917.20181203
> xf86-video-amdgpu-18.1.0
> drm-fbsd12.0-kmod-4.16.g20190305 (amdgpu, i915, and radeon DRM modules for the linuxkpi-based KMS components. Currently corresponding to Linux 4.16 DRM.)
> 
> amdgpu is working fine with external screens and intel with internal,
> but i cannot get them working together.
> 
> in xorg.conf i can specify:
> Section "ServerLayout"
> 	Screen      0  "External"
> 	Screen      1  "Primary" LeftOf "External"
> 
> or
> Section "ServerLayout"
>   Screen      0  "Primary" 0 0
>   Screen      1  "External" RightOf "Primary"
> 
> in each case only one provider is recognized by xrandr (amdgpu in the first case and intel in second)
> and i can access another screen via f.e.
> DISPLAY=:0.1 urxvt &

This is because your xorg.conf sets up both GPUs as primary screens
(so-called "traditional multihead", as this was the first kind of
multi-GPU configuration supported by X).

In order to use the second GPU as an RandR provider, you need to leave
it unconfigured in xorg.conf, then Xorg should automatically set it up
as a so-called "GPU" screen.


-- 
Earthling Michel Dänzer               |              https://www.amd.com
Libre software enthusiast             |             Mesa and X developer