On Thu, Aug 16, 2018 at 3:16 PM, Daniel Vetter daniel@ffwll.ch wrote:
On Thu, Aug 16, 2018 at 11:21 PM, John Stultz john.stultz@linaro.org wrote:
On Thu, Aug 16, 2018 at 1:46 PM, Daniel Vetter daniel@ffwll.ch wrote:
You happen to have set drm_fb_overalloc respectively CONFIG_DRM_FBDEV_OVERALLOC? Was added so that mali blob can pageflip, would explain what's going on at least.
Yep. CONFIG_DRM_FBDEV_OVERALLOC is set to 200.
So ->max_height is indeed the limit (or should be, minus driver bugs) for framebuffers. That's enforced in drm_framebuffer_create_internal for everything (both ioctl and should also for all internal callers), except the cma helpers never made sure this is correct. So I'd call this a bugfix.
Sure. I'm really not sure where the max_height=2048 comes from (and if its the real limitation or a vendor guessed value - the hikey960 driver I have uses the same), but yea, the old code wasn't checking it.
Now the question is whether the fbdev page-flipping actually worked on older kernels for you or not ...
It sure seems to work ok with the changes reverted. Any suggestion on how to check this?
thanks -john