buddies! I have a hybrid laptop(sorry) with AMD A10 cpu (integrated with R5 graphic) and isolated Radoen R7 Topaz graphic.
The Ubuntu 16.04.6 was run on this box more than 2 years.Ubuntu just disable the R7 and drives the R5. Then my box run X/Gnome normally. Recently, I wanna install a more Free GNU/linux on this laptop, then I tried Debian9 and trisquel8(16.04 based). But Both of them have shown same problem, which the amdgpu for R5 could not be loaded and only the VESA modules be loaded when system boot.
For example, in Debian:
~$ inxi -G Graphics: Card-1: Advanced Micro Devices [AMD/ATI] Carrizo Card-2: Advanced Micro Devices [AMD/ATI] Topaz XT [Radeon R7 M260/M265 / M340/M360 / M440/M445] Display Server: X.Org 1.19.2 drivers: ati,vesa (unloaded: modesetting,fbdev,radeon) Resolution: firstname.lastname@example.org GLX Renderer: Gallium 0.4 on llvmpipe (LLVM 3.9, 128 bits) GLX Version: 3.0 Mesa 13.0.6
Your can see the driver is ati && vesa, the radeon(xserver-xorg-video-ati/radeon) for R7 is not be loaded.
As well as /var/log/Xorg.0.log:
~$ less /var/log/Xorg.0.log | grep -iE "unload" alxandernash@debianalxander:~$ less /var/log/Xorg.0.log | grep -iE "unload" [ 4.062] (II) UnloadModule: "modesetting" [ 4.062] (II) UnloadModule: "fbdev" [ 4.062] (II) UnloadSubModule: "fbdevhw" [ 4.191] (II) UnloadModule: "radeon" [ 4.191] (II) Unloading radeon
the loaded modules actually is VESA as shown: (sorry a little bit long, see 4.038)
~$ less /var/log/Xorg.0.log | grep -iE "load" ... [ 4.038] (II) LoadModule: "vesa" ...
However, nothing log info about amdgpu in Xorg.0.log This vesa module could build the X, but with big Fan noise and uncontrollable screen brightness as well as uncontrollable resolution.
This issue happens on Debian9 and Trisquel8 with almost same situation. I have tred to remove the xserver-xorg-video-vesa or add modprob.blacklist=vesa in _CMDLINE_LINUX_ of /etc/default/grub and add blacklist vesa in blacklist.conf. At the same time, I also add amdgpu in /etc/modules(might be this name). The result is system can not be booted in to desktop(make sence if the amdgpu module isn't correctly loaded).
Thanks for reading until here about my story.So, my question is how to make debian9 load the amdgpu other than vesa