Re: [Intel-gfx] [PATCH 4/5] drm/vblank: Restoring vblank counts after device PM events.

2018-01-19 Thread Rodrigo Vivi
On Fri, Jan 19, 2018 at 10:02:12PM +, Pandiyan, Dhinakaran wrote: > > > > On Fri, 2018-01-19 at 00:01 -0800, Rodrigo Vivi wrote: > > On Fri, Jan 12, 2018 at 09:57:06PM +, Dhinakaran Pandiyan wrote: > > > The HW frame counter can get reset if device enters a low power state > > > after >

Re: [Intel-gfx] [PATCH 4/5] drm/vblank: Restoring vblank counts after device PM events.

2018-01-19 Thread Pandiyan, Dhinakaran
On Fri, 2018-01-19 at 00:01 -0800, Rodrigo Vivi wrote: > On Fri, Jan 12, 2018 at 09:57:06PM +, Dhinakaran Pandiyan wrote: > > The HW frame counter can get reset if device enters a low power state after > > vblank interrupts were disabled. This messes up any following vblank count > > update

Re: [PATCH 4/5] drm/vblank: Restoring vblank counts after device PM events.

2018-01-19 Thread Rodrigo Vivi
On Fri, Jan 12, 2018 at 09:57:06PM +, Dhinakaran Pandiyan wrote: > The HW frame counter can get reset if device enters a low power state after > vblank interrupts were disabled. This messes up any following vblank count > update as a negative diff (huge unsigned diff) is calculated from the HW

[PATCH 4/5] drm/vblank: Restoring vblank counts after device PM events.

2018-01-12 Thread Dhinakaran Pandiyan
The HW frame counter can get reset if device enters a low power state after vblank interrupts were disabled. This messes up any following vblank count update as a negative diff (huge unsigned diff) is calculated from the HW frame counter change. We cannot ignore negative diffs altogther as there co