During Boot-Up, I get the following errors in the system log:
kernel: [ 1.495711] i915 0000:00:02.0: Invalid ROM contents
kernel: [ 1.495768] [drm:intel_parse_bios] *ERROR* VBT signature missing
kernel: [ 1.495825] [drm] failed to find VBIOS tables
System runs without problems despite these errors showing up.
-- chipset: 945GM/GMS, 943/940GML (not sure which one I got)
-- system architecture: 32-bit
-- kernel: 3.1
-- Linux distribution: Arch Linux
-- Machine: Apple Macbook 1,1
Boot in EFI mode, *not* BIOS mode.
I tried to trace where these errors originate and it seems they are caused in i915_load_modeset_init() in linux/drivers/gpu/drm/i915/i915_dma.c when it tries to load the Video ROM (line 1234).
The ROM can't be dumped:
cat: /sys/devices/pci0000:00/0000:00:02.0/rom: Input/output error
Really this should just be a warning rather than error, since as you found out we can often survive...
(In reply to comment #1)
> Really this should just be a warning rather than error, since as you found out
> we can often survive...
Out of curiosity: On which systems is the VBIOS needed and on which not?
Created attachment 57597 [details] [review]
Downgrade ERROR message
A patch referencing this bug report has been merged in Linux v3.4-rc1:
Author: Chris Wilson <firstname.lastname@example.org>
Date: Fri Feb 24 16:53:28 2012 +0000
drm/i915/bios: Downgrade the "signature missing" DRM_ERROR to debug
And the error is squelched. Thanks for the bug report.