[PATCH 4/4] drm/radeon: unpin cursor BOs before suspend

[Grigori Goronzy]

On 2015-07-03 05:30, Michel Dänzer wrote:
> 
> This could be done in the same loop as the front buffers.
> 

Sure, I just thought it looks cleaner this way.

> On resume, the cursor BO is currently pinned again by
> radeon_cursor_reset -> radeon_set_cursor. However, radeon_cursor_reset
> is also called when changing the video mode, in which case it causes 
> the
> cursor BO pin count to increase by 1 for each CRTC using it. 
> Presumably,
> the mouse cursor would end up broken again on suspend/resume after that
> for you.
> 

Indeed. It seems to be problematic overall that radeon_cursor_reset does 
unconditionally increment the pin count. As soon as a mode is switched 
with cursor enabled, the cursor BO will stay pinned forever.

> We need a solution which pins the BO again on resume but doesn't
> increase the pin count during a mode change. I'm not sure right now 
> what
> the best way is to achieve that, I'll think about it more later.

How about this:

Never let radeon_set_cursor mess with the pin count, do that in 
radeon_crtc_cursor_set2 only, and make sure that the reference^Wpin 
count is updated accordingly (i.e. exactly one pin per crtc). Then add 
some explicit cursor resume code that traverses the crtc list and 
re-pins as needed. Maybe that that nice, but should work.

Grigori