https://bugs.freedesktop.org/show_bug.cgi?id=108356

Bug ID: 108356 Summary: AMD DC: Mullins APU: Possible race condition between vblank interrupt and atomic pageflip Product: DRI Version: DRI git Hardware: Other OS: All Status: NEW Severity: normal Priority: medium Component: DRM/AMDgpu Assignee: dri-devel@lists.freedesktop.org Reporter: issor.oruam@gmail.com

Created attachment 142019 --> https://bugs.freedesktop.org/attachment.cgi?id=142019&action=edit Screen without issue

Hi,

while doing tests with AMD DC on Mullins APU (Acer ES1-521) a visual problem has been observed on HDMI output to LCD monitor

From visual point of view there is a trapezoidal shape at the top of screen

appearing from time to time, but it lasts a fraction of second.

Stack: drm_hwcomposer + gbm_gralloc with AMD DC Kernel: all kernels from 4.16 to 4.19rc7 are impacted

I would like to understand what irq/signals are involved in the screen scanout and how to trace/profile the problem in Android. NOTE: even disabling the HWC, by forcing GPU compositing the problem is still happening.

The problem does not happen at all with Bonaire (HD7790) and Polaris (RX560) Visual representation of the rapid glitches in the attach

Thanks for any help

Mauro android-x86 team