On 04.11.2015 00:03, Pavel Machek wrote:
> Hi!
>
>
>>>>>>> Any ideas?
>>>>>> Alex probably knows more about this, but it sounds like problems with
>>>>>> switching the memory clocks on 3D load.
>>>>>> Try to disable power management completely with radeon.dpm=0 on the
>>>>>> kernel
>>>>>> command line or nailing the hardware at a specific power level using
>>>>>> sysfs.
>>>>> I tried that, but it still flickers.
>>>> It's probably pll stability. There seem to be a number of regressions
>>>> since the pll code was rewritten to support matching the hdmi clocks
>>>> more closely. Does this patch help?
>>>>
>>>> diff --git a/drivers/gpu/drm/radeon/atombios_crtc.c
>>>> b/drivers/gpu/drm/radeon/atombios_crtc.c
>>>> index dac78ad..b86f06a 100644
>>>> --- a/drivers/gpu/drm/radeon/atombios_crtc.c
>>>> +++ b/drivers/gpu/drm/radeon/atombios_crtc.c
>>>> @@ -569,6 +569,8 @@ static u32 atombios_adjust_pll(struct drm_crtc *crtc,
>>>> radeon_crtc->pll_flags = 0;
>>>>
>>>> if (ASIC_IS_AVIVO(rdev)) {
>>>> + radeon_crtc->pll_flags |= RADEON_PLL_PREFER_MINM_OVER_MAXP;
>>>> +
>>>> if ((rdev->family == CHIP_RS600) ||
>>>> (rdev->family == CHIP_RS690) ||
>>>> (rdev->family == CHIP_RS740))
>>>>
>>> Help.. maybe... it is tricky to tell. It definitely does _not_ fix the
>>> issue completely.
>> You could also try the old pll algorithm:
> I reverted the patch above, and switched to the old algorithm.
>
> The flicker is still there. (But maybe its less horrible, like with
> RADEON_PLL_PREFER_MINM_OVER_MAXP).
The flickering would vanish completely if that's the reason for the
issue you are seeing.
Try setting ref_div_min and ref_div_max to 2 in radeon_compute_pll_avivo().
But I'm not 100% convinced that this is actually a PLL problem, try to
compile the firmware it complains about into the kernel as well.
Regards,
Christian.
>
> Thanks,
> Pavel
>
