[Intel-gfx] [PATCH 08/11] drm/intel: add enable_psr module option and disable psr by default

[Rodrigo Vivi]

On Mon, Jul 15, 2013 at 7:01 PM, Chris Wilson <chris at chris-wilson.co.uk> wrote:
> On Mon, Jul 15, 2013 at 05:23:35PM -0300, Rodrigo Vivi wrote:
>> On Mon, Jul 15, 2013 at 11:01 AM, Chris Wilson <chris at chris-wilson.co.uk> wrote:
>> > On Thu, Jul 11, 2013 at 06:45:02PM -0300, Rodrigo Vivi wrote:
>> >> v2: prefer seq_puts to seq_printf detected by Paulo Zanoni.
>> >> v3: PSR is disabled by default. Without userspace ready it
>> >>     will cause regression for kde and xdm users
>> >
>> > I think we should still aim to enable by default and disable on the
>> > first direct access after a mmioflip.
>>
>> unfortunately I couldn't implement a reliable way of detect it without
>> false positives,
>
> Can you give me an example of one of the false positives? The detect
> front buffer writes patches we had should be good enough to only punish
> legacy userspace.

psr works very well on unity and gnome and disable it in the cases it
already works well is a kind of false positive...
I didn't mean false positive in terms of error in detection, but
disabling when not really needed.

>
>> so let's put this disabled for now and revert when I find a reliable way.
>
> That's fine, just think we're giving up too easily ;-)

Yes, I am! tell you more on irc ;)

> -Chris
>
> --
> Chris Wilson, Intel Open Source Technology Centre



--
Rodrigo Vivi
Blog: http://blog.vivi.eng.br