On Tue, May 28, 2019 at 07:42:19PM -0600, Jeffrey Hugo wrote: > > > Do you know if the nexus 5 has a video or command mode panel? There > > > is some glitchyness with vblanks and command mode panels. > > > > Its in command mode. I know this because I see two 'pp done time out' > > messages, even on 4.17. Based on my understanding, the ping pong code is > > only applicable for command mode panels. > > Actually, the ping pong element exists in both modes, but 'pp done > time out' is a good indicator that it is command mode. > > Are you also seeing vblank timeouts? Yes, here's a snippet of the first one. [ 2.556014] WARNING: CPU: 0 PID: 5 at drivers/gpu/drm/drm_atomic_helper.c:1429 drm_atomic_helper_wait_for_vblanks.part.1+0x288/0x290 [ 2.556020] [CRTC:49:crtc-0] vblank wait timed out [ 2.556023] Modules linked in: [ 2.556034] CPU: 0 PID: 5 Comm: kworker/0:0 Not tainted 5.2.0-rc1-00178-g72c3c1fd5f86-dirty #426 [ 2.556038] Hardware name: Generic DT based system [ 2.556056] Workqueue: events deferred_probe_work_func ... > Do you have busybox? > > Can you run - > sudo busybox devmem 0xFD900614 > sudo busybox devmem 0xFD900714 > sudo busybox devmem 0xFD900814 > sudo busybox devmem 0xFD900914 > sudo busybox devmem 0xFD900A14 # busybox devmem 0xFD900614 0x00020020 # busybox devmem 0xFD900714 0x00000000 # busybox devmem 0xFD900814 0x00000000 # busybox devmem 0xFD900914 0x00000000 # busybox devmem 0xFD900A14 0x00000000 I get the same values with the mainline kernel and 4.17. Brian
