[Intel-gfx] [PATCH 1/3] drm/i915: Make fb user dirty operation to invalidate frontbuffer

[Chris Wilson]

On Tue, Jun 30, 2015 at 04:42:00PM -0700, Rodrigo Vivi wrote:
> Let's do a frontbuffer invalidation on dirty fb.
> To be used for DIRTYFB drm ioctl.
> 
> This patch solves the biggest PSR known issue, that is
> missed screen updates during boot, mainly when there is a splash
> screen involved like plymouth.
> 
> Plymoth will do a modeset over ioctl that flushes frontbuffer
> tracking and PSR gets back to work while it cannot track the
> screen updates and exit properly. However plymouth also uses
> a dirtyfb ioctl whenever updating the screen. So let's use it
> to invalidate PSR back again.
> 
> v2: Remove ORIGIN_FB_DIRTY and use ORIGIN_GTT instead since dirty
>     callback is just called after few screen updates and not on
>     everyone as pointed by Daniel.
> 
> Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
> Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>

Will it ever grow the ability to handle clip rects? I can detect the
presence of the syscall and call it appropriately, but I don't want to
have to start tracking frontbuffer damage unless there's a significant
advantage in doing so (to offset the cost of the tracking).
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre