[PATCH] drm/amdgpu: expose amdgpu_sensors on pre-powerplay chips

[Tom St Denis]

On 14/02/17 09:56 PM, Deucher, Alexander wrote:
>> -----Original Message-----
>> From: Michel Dänzer [mailto:michel at daenzer.net]
>> Sent: Tuesday, February 14, 2017 9:52 PM
>> To: Deucher, Alexander; 'Samuel Pitoiset'; StDenis, Tom
>> Cc: amd-gfx at lists.freedesktop.org
>> Subject: Re: [PATCH] drm/amdgpu: expose amdgpu_sensors on pre-
>> powerplay chips
>>
>> On 15/02/17 01:17 AM, Deucher, Alexander wrote:
>>>> From: amd-gfx [mailto:amd-gfx-bounces at lists.freedesktop.org] On
>> Behalf
>>>> Of Samuel Pitoiset
>>>>
>>>>> Otherwise, it seems to work though the GPU_TEMP reads as "5000" on
>> my
>>>>> Kaveri (meaning temp of 5C which isn't true).
>>>>>
>>>>> I suspect the dpm code is reading the wrong register to get the temp but
>>>>> we can fix that in another change later on.
>>>>
>>>> No idea. It was just a copy-n-paste. Maybe the initial code is buggy?
>>>
>>> I don’t know that the GPU temp sensor on CI based APUs actually works
>>> properly.  I think the package temperature is exposed via the CPU
>>> thermals.
>>
>> Seems to work fine with radeon on my two Kaveri laptops, FWIW.
>>
>> On my desktop Kaveri, unplausibly low values (around 9-10C) are reported
>> at idle for both GPU and CPU. With load, both go up to around 30C, so it
>> seems like the values make sense in a relative sense but not in an
>> absolute one.
>
> I think  I vaguely recall that it might actually be power rather than temperature.  Need to check with the SMU guys.


On my retail kaveri (with latest bios...) it seems to track with load 
but isn't really accurate (it'll jump double digits back and forth)

Eitherway though if Samuel updates the patches to include a check for 
amdgpu_drm we should be able to commit them.

I've already created a patch for umr to read them, just waiting on the 
kernel side to land.

Tom