Hybrid graphics - "radeon" driver unloaded, "modesetting" loaded?

[Michel Dänzer]

On 10.02.2016 23:43, Alex Deucher wrote:
> On Wed, Feb 10, 2016 at 7:58 AM, Lennert Van Alboom
> <lennert at vanalboom.org> wrote:
>> On Fri, Feb 05, 2016 at 11:24:12AM +0900, Michel Dänzer wrote:
>>> On 04.02.2016 19:05, Lennert Van Alboom wrote:
>>>> Hello. I've got a HP Elitebook 850g1 with hybrid graphics:
>>>>
>>>>     $ lspci | grep VGA
>>>>     00:02.0 VGA compatible controller: Intel Corporation Haswell-ULT Integrated Graphics Controller (rev 0b)
>>>>     03:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Mars [Radeon HD 8730M] (rev ff)
>>>>
>>>>     $ sudo cat /sys/kernel/debug/vgaswitcheroo/switch
>>>>     0:IGD:+:Pwr:0000:00:02.0
>>>>     1:DIS-Audio: :Off:0000:03:00.1
>>>>     2:DIS: :DynOff:0000:03:00.0
>>>>
>>>> I'm running Debian (sid, x86_64) with kernel 4.4.0-trunk-amd64 (same happens with the 4.3.0-1-amd64 kernel) and Xorg 1:7.7+13 (1.18.0).
>>>> I'm having an odd issue where Xorg loads the correct "radeon" driver, but after a split second, unloads it again and loads "modesetting":
>>>>
>>>>     [    13.688] (II) config/udev: removing GPU device /sys/devices/pci0000:00/0000:00:1c.4/0000:03:00.0/drm/card1 /dev/dri/card1
>>>>     [    13.688] xf86: remove device 1 /sys/devices/pci0000:00/0000:00:1c.4/0000:03:00.0/drm/card1
>>>>     [    13.693] (II) UnloadModule: "radeon"
>>>>     [    13.693] (II) UnloadSubModule: "fb"
>>>>     [    13.693] (II) Unloading fb
>>>>     [    13.693] (II) UnloadSubModule: "glamoregl"
>>>>     [    13.693] (II) Unloading glamoregl
>>>>     [    13.693] (II) config/udev: Adding drm device (/dev/dri/card1)
>>>>     [    13.693] (II) xfree86: Adding drm device (/dev/dri/card1)
>>>>     [    13.693] (II) LoadModule: "modesetting"
>>>>     [    13.693] (II) Loading /usr/lib/xorg/modules/drivers/modesetting_drv.so
>>>>
>>>> Full Xorg log at http://ziff.soleus.nu/Xorg.0.log.txt. I don't have a xorg.conf, and no snippets in xorg.conf.d either.
>>>>
>>>> This results in two providers in xrandr, Intel and modesetting (as opposed to radeon, as I had before):
>>>>
>>>>     $ xrandr --listproviders
>>>>     Providers: number : 2
>>>>     Provider 0: id: 0x7d cap: 0xb, Source Output, Sink Output, Sink Offload crtcs: 4 outputs: 6 associated providers: 0 name:Intel
>>>>     Provider 1: id: 0x140 cap: 0x3, Source Output, Sink Output crtcs: 2 outputs: 2 associated providers: 0 name:modesetting
>>>>
>>>> I can't set an offload sink:
>>>>
>>>>     $ xrandr --setprovideroffloadsink modesetting Intel
>>>>     X Error of failed request:  BadValue (integer parameter out of range for operation)
>>>>     Major opcode of failed request:  140 (RANDR)
>>>>     Minor opcode of failed request:  34 (RRSetProviderOffloadSink)
>>>>     Value in failed request:  0x140
>>>>     Serial number of failed request:  16
>>>>     Current serial number in output stream:  17
>>>>
>>>> And, I suppose this is normal because of the above, DRI_PRIME doesn't do much:
>>>>
>>>>     $ glxinfo | grep "OpenGL renderer"
>>>>     OpenGL renderer string: Mesa DRI Intel(R) Haswell Mobile
>>>>     $ DRI_PRIME=1 glxinfo | grep "OpenGL renderer"
>>>>     OpenGL renderer string: Mesa DRI Intel(R) Haswell Mobile
>>>>
>>>> Strangely enough, the /sys device link for "card1", as mentioned in the Xorg log, still points to the "correct" ATI device:
>>>>
>>>>     $ ls -l /sys/class/drm/card1/device
>>>>     lrwxrwxrwx 1 root root 0 Feb  3 21:14 /sys/class/drm/card1/device -> ../../../0000:03:00.0
>>>>
>>>>
>>>> I'm a bit stumped here. How can I get my radeon device back in the xrandr providers and working via DRI_PRIME?
>>>
>>> I can see two problems here: Xorg unloads the radeon driver and loads
>>> the modesetting driver instead, and the modesetting driver doesn't
>>> advertise PRIME render offloading capability. I don't think either is a
>>> radeon driver issue though, so the xorg-devel list seems more
>>> appropriate. Moving there.
>>
>>
>> Okay. The second problem isn't much of a problem (for me, personally) if the
>> first gets resolved, so I suppose it makes sense to look at that first.
>>
>> Why would Xorg unload a valid driver for a card and load another instead? And,
>> more to the point, is there a way of preventing it from happening?
> 
> Possibly an old version of the driver that is missing the pci id for
> the asic you have.

That's not consistent with the log file: The radeon driver loads and
fully initializes successfully, but then for some reason (apparently
udev related), the radeon driver is unloaded and the modesetting driver
is loaded instead for the Radeon GPU.


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