Created attachment 132989 [details]
if I try to use a resolution greater then 4096 in either direction the displays stay black and the kernel logs:
[drm:drm_ioctl [drm]] pid=1986, dev=0xe200, auth=1, DRM_IOCTL_MODE_ADDFB
[drm:intel_framebuffer_init [i915]] tiled pitch (23040) must be at less than 16384
[drm:drm_internal_framebuffer_create [drm]] could not create framebuffer
[drm:drm_ioctl [drm]] ret = -22
From the error message I assume that the stride is somehow wrong so I filled the bug against mesa because the stride is calculated by mesa's
The maximum allowed stride is set in the kernel and is hardware dependent so this may only occur on cherryview.
xrandr with modesetting says the maximum framebuffer is 8192x8192 and when using the intel driver and SNA acceleration it is working. So the hardware should support a greater resolution.
Kernel: 4.9.30 32Bit
Created attachment 132990 [details]
kernel output with drm debug
Created attachment 132991 [details]