Dear Kroms,
Am Montag, den 13.07.2015, 09:43 +0200 schrieb kroms@posteo.be:
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There are two more things two do.
- Contact the Linux i915 folks and ask them, if the module is able
to detect the configuration itself and does not rely on the firmware or if there is a way to override that setting from the Linux command line.
Who is going to do this? Is this [1] the right community? I am not sure, if I am able to explain it right. If you want me to do this, what do you mean exactly with "the module", is it "i915"?
Yes i915 and it’d be great if you could do it.
At least the second question should be answered. Looking at `/sbin/modinfo i915` it shows that there is such an option already.
parm: lvds_channel_mode:Specify LVDS channel mode (0=probe BIOS [default], 1=single-channel, 2=dual-channel) (int)
So you could add `i915.lvds_channel_mode=2`, I think, to the Linux command line and see if Linux is able to initialize your system.
On [2], is written: "Linux (kernel) has its own init code (including EDID parsing). The current suspicion is that coreboot's own initialization code has buggy EDID parsing in some way, such that the proper settings for the panel are not used, leading to the failure."
Please tell me, if I understand it right: The kernel module should not rely on coreboot concerning the settings for the display and you want to know, if the kernel module is able to get the needed information direct from the display (EDID)? If this is possible, you want to know, if this is configurable with the Linux command line? Means "Linux command line" the same as "kernel command line"?
Yes. But I am not sure if it’s related to EDID parsing at all. coreboot just hard codes it.
- Improve coreboot so that the LVDS link configuration is detected
during runtime as the vendor firmware (VGA Option ROM/Video BIOS(?)) does.
While I am learning a lot of things working on this issue, this is far above my skills.
No problem. Maybe somebody else will do it.
Thanks,
Paul
[1] https://01.org/linuxgraphics/community/kernel [2] http://libreboot.org/docs/hcl/gm45_lcd.html