[PATCH 2/6] drm/radeon: remove HDMI interrupts on Evergreen

[Alex Deucher]

On Mon, Apr 15, 2013 at 4:08 AM, Christian König
<deathsimple at vodafone.de> wrote:
> Am 14.04.2013 20:02, schrieb Rafał Miłecki:
>
>> 2013/4/14 Alex Deucher <alexdeucher at gmail.com>:
>>>
>>> On Sun, Apr 14, 2013 at 11:55 AM, Rafał Miłecki <zajec5 at gmail.com> wrote:
>>>>
>>>> 2013/4/14 Alex Deucher <alexdeucher at gmail.com>:
>>>>>
>>>>> On Sat, Apr 13, 2013 at 7:26 PM, Rafał Miłecki <zajec5 at gmail.com>
>>>>> wrote:
>>>>>>
>>>>>> We need interrupts on format change for R6xx only, where hardware
>>>>>> seems
>>>>>> to be somehow bugged and requires setting audio info manually.
>>>>>
>>>>> Can you confirm that this is actually needed on older chips?  AFAIK,
>>>>> it shouldn't be required for any chips.  It's mainly for debugging.
>>>>
>>>> I can't really right now :( My notebook with RV620 died (hard disk
>>>> ended it's life and power cable got broken). I hope to resurrect him
>>>> in about a week.
>>>>
>>>> If that isn't needed on R6xx, I'm not sure why we implemented it in
>>>> first place at all. Christian? Do you have idea why this was required?
>>>> I remember than in first place we were using timer, then we switched
>>>> to the interrupts. But why we needed it at all?
>>>
>>> I suspect it was just assumed to be necessary due to the original RE.
>>
>> I'm OK with removing that from R6xx too, if it's not needed. I just
>> want to check that first, to don't break audio accidentally. In case
>> of Evergreen I was able to test it, so I dares to submit this patch ;)
>
>
> Well, originally I was just imitating fglrx behavior with this, but since I
> now have access to the AMD documentation I can't find a reason why fglrx was
> actually doing it like this. In theory format changes should work on their
> own, but it is still possible they did this because of some bug or something
> like this.
>
> I can't really test it anymore either, so no idea if it is really required
> or not.

For both evergreen and older asics, maybe rather than removing the
code, we could just disable the interrupt src.  I.e., remove the call
to radeon_irq_kms_enable_afmt().  That way we can always re-enable it
if we need it for testing or debugging.

Alex