Re: [PATCH] drm/i915: Add Baytrail PSR Support.

[Daniel Vetter <daniel@ffwll.ch>]

On Wed, Jan 29, 2014 at 12:55:35PM -0200, Rodrigo Vivi wrote:
> This patch adds PSR Support to Baytrail.
> 
> Baytrail cannot easily detect screen updates and force PSR exit.
> So we inactivate it on {busy_ioctl, sw_finish and mark_busy}
> and update to enable it back on next display mark_idle.
> 
> v2: Also inactivate PSR on cursor update.
> v3: Inactivate PSR on mark_busy, dset_domain and sw_finish_ioctl, and
>     early on page flip besides avoid initializing inactive/active flag
>     more than once.
> v4: Fix identation issues.
> v5: Rebase and add Baytrail per pipe support although leaving PIPE_B
>     support disabled by for now since it isn't working properly yet.
> v6: Removing forgotten comment and useless clkgating definition.
> v7: Remove inactivate from set_domain. Chris warned this was semanticaly
>     wrong.

Like I've said I agree that it's not pretty, but I also think it's the
only thing we can do atm. For fbc we have the hardware-based fence
tracking, but it sounds like that's busted for psr on byt.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch