[Linux v4.3-rc6] i915: issues with Skylake integrated graphics

From: Eric Biggers
Date: Thu Oct 22 2015 - 22:34:19 EST


Hi,

I am testing Linux v4.3-rc6 on a laptop with Intel 'Skylake' integrated
graphics. The integrated display works, but I noticed several warnings in the
kernel log, and a VGA monitor attached to the HDMI input via a VGA->HDMI adapter
did not work. Furthermore, the system hung for several seconds during boot.
The two WARNs were:

[ 1.078097] WARNING: CPU: 0 PID: 1 at drivers/gpu/drm/i915/intel_pm.c:3321 skl_update_pipe_wm+0x7fa/0x810()
[ 1.078097] WARN_ON(p->pixel_rate == 0)
...
[ 1.353670] WARNING: CPU: 1 PID: 6 at drivers/gpu/drm/i915/intel_dp.c:854 intel_dp_aux_ch+0x10f/0x6a0()
[ 1.353670] dp_aux_ch not started status 0xad40001f

The following error was reported later, when the HDMI input was connected but
the driver failed to report the input as connected:

[ 52.553940] [drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 130

I have attached the full 'dmesg' output for anyone who may find it useful.

Eric

Attachment: dmesg.gz
Description: Binary data