Troubleshooting LVDS on GM45.

2016-04-01 Thread Rob Kramer
Hi, My setup is an embedded GM45 based board with a screen connected via 24 bit LVDS. When trying a to use a newer kernel (3.14.57) with KMS, the screen stays blank. I'm only testing KMS so far, no X. Older, pre-KMS versions of the kernel worked fine. I'm hoping that a resident Intel DRM guru

Troubleshooting LVDS on GM45.

2016-04-01 Thread Rob Kramer
On 04/01/2016 04:01 PM, Jani Nikula wrote: > On Fri, 01 Apr 2016, Rob Kramer wrote: >> My setup is an embedded GM45 based board with a screen connected via 24 >> bit LVDS. When trying a to use a newer kernel (3.14.57) with KMS, the >> screen stays blank. I'm only testi

Troubleshooting LVDS on GM45 (kernel 4.5.0)

2016-04-01 Thread Rob Kramer
Rob On 04/01/2016 12:49 PM, Rob Kramer wrote: > Hi, > > My setup is an embedded GM45 based board with a screen connected via > 24 bit LVDS. When trying a to use a newer kernel (3.14.57) with KMS, > the screen stays blank. I'm only testing KMS so far, no X. Older, >

Troubleshooting LVDS on GM45 (kernel 4.5.0)

2016-04-04 Thread Rob Kramer
I've tried again without video parameter -- same outcome. I've also applied Ville's patch "drm/i915: Read timings from the correct transcoder in intel_crtc_mode_get()" (with teeny backport fix). It seems this code is never called in my case though, since intel_lvds_init() chooses to use the VBT

Troubleshooting LVDS on GM45 (kernel 4.5.0)

2016-04-05 Thread Rob Kramer
On 04/04/2016 10:58 PM, Ville Syrjälä wrote: > >> Since this VBT mode is probably junk anyway, I commented out the >> if-statement that selects it (in intel_lvds.c), so that the code will >> pick the mode as set by BIOS. The result is much better, I actually get >> proper looking output! X also r