[ltp] Z61m, ATI Technologies Inc Radeon Mobility X1400, Debian Sid

[Alex Deucher]

On Tue, Feb 8, 2011 at 5:25 PM, Henrique de Moraes Holschuh
<hmh@hmh.eng.br> wrote:
> On Tue, 08 Feb 2011, Alex Deucher wrote:
>> > FWIW, 2.6.35.11 + Debian Squeeze, KMS enabled, _all power management
>> > disabled_ is stable on a Radeon X300 (T43). =A0 Enable automatic GPU p=
ower
>> > management, and you get unknown NMIs when it switches power management
>> > profiles (i.e. the driver is causing the GPU to mess the PCIe bus).
>>
>> These are caused by changing the pcie link size (e.g., 16x -> 1x) to
>> save power. =A0I'm not sure how to avoid them. =A0You can disable the
>> relevant code in the driver, but the link changes should be safe.
>
> Can't the PCIe link size transition be synchronized with the GPU (i.e.
> quiesce it before transitioning, so that it does not generate any traffic
> before the retrain is finished?).

It is.  The GPU should be idle and all gpu buffers unmapped before the
link is changed.

>
> Otherwise, it might be a good idea to actually move the NMI handler out o=
f
> the dark ages, and teach it about PCie errors...

I'm not that familiar with the pcie NMI stuff unfortunately.

Alex

>
> --
> =A0"One disk to rule them all, One disk to find them. One disk to bring
> =A0them all and in the darkness grind them. In the Land of Redmond
> =A0where the shadows lie." -- The Silicon Valley Tarot
> =A0Henrique Holschuh
>