[Intel-gfx] Intel Arc A370M vs Linux 5.19

[Tvrtko Ursulin]

On 15/09/2022 15:54, Rodrigo Vivi wrote:
> On Thu, Sep 15, 2022 at 10:40:59PM +0800, Daniel J Blueman wrote:
>> On Thu, 15 Sept 2022 at 22:09, Rodrigo Vivi <rodrigo.vivi at intel.com> wrote:
>>> On Thu, Sep 15, 2022 at 09:08:08PM +0800, Daniel J Blueman wrote:
>>>> Dear Intel et al,
>>>>
>>>> With a HP Spectre x360 16 16-f1xxx/891D (Intel i7-1260P) with an Arc
>>>> A370M GPU [1] running the latest Ubuntu 22.10 5.19.0-15-generic
>>>> kernel, we see:
>>>>
>>>> i915 0000:03:00.0: Your graphics device 5693 is not properly supported
>>>> by the driver in this kernel version. To force driver probe anyway,
>>>> use i915.force_probe=5693
>>>>
>>>> Since the GPU is unmanaged, battery life is around 30% of what it
>>>> could be. Unsurprisingly, adding i915.force_probe=5693 causes
>>>> additional  issues. Given a lack of BIOS option to disable the GPU, is
>>>> there any advice for Linux support or at least putting the GPU into
>>>> D3? I see only Windows drivers on the official support page [2], and
>>>> Linux 6.0-rc5 isn't buildable [3].
>>>
>>> I believe this is what you are looking for:
>>>
>>> echo auto | sudo tee /sys/bus/pci/devices/0000\:03\:00.0/power/control
>>>
>>> In Linux the default is to keep the unmanaged devices in D0.
>>> But changing the rpm to auto should transition the device to D3.
>>>
>>> You can go further and check with the lspci -vv if there are other
>>> unmanaged devices in the same pci root tree and also add them to the
>>> 'auto' rpm so you can even achieve D3cold in that whole device, what
>>> gives you extra power savings.
>>>
>>> I hope this helps for now.
>>
>> Yes, I was also hoping this would work as we see D3hot is supported:
>>
>> # echo auto > /sys/bus/pci/devices/0000\:03\:00.0/power/control
>> # lspci -vvvs 03:00.0
>> ...
>> Capabilities: [d0] Power Management version 3
>>          Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA
>> PME(D0+,D1-,D2-,D3hot+,D3cold-)
>>          Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
>>                  ^^
>>
>> However it stays in D0 with PME disabled as we see. "Kernel modules:
>> i915" may suggest the i915 driver holds a reference to it, preventing
>> the transition.
> 
> Oh, yes. I was thinking more on using the command line I sent when
> the i915 is not probed. i.e. without using the force probe. your first
> scenario.

Could it help to bind DG2 to vfio-pci and so prevent i915 touching it?

Regards,

Tvrtko