Bug 207999 - Screen goes black when loaded i915kms
Summary: Screen goes black when loaded i915kms
Status: Closed Overcome By Events
Alias: None
Product: Base System
Classification: Unclassified
Component: kern (show other bugs)
Version: CURRENT
Hardware: amd64 Any
: --- Affects Some People
Assignee: freebsd-bugs (Nobody)
URL:
Keywords: i915
Depends on:
Blocks:
 
Reported: 2016-03-14 21:53 UTC by Johannes Lundberg
Modified: 2017-06-22 09:19 UTC (History)
3 users (show)

See Also:

Attachments
dmesg (26.95 KB, text/plain)
2016-03-14 21:53 UTC, Johannes Lundberg 		no flags Details
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Description Johannes Lundberg 2016-03-14 21:53:46 UTC 
Created attachment 168187 [details]
dmesg

Hardware
2012 Macbook Air (Sandybridge)

Brightness is set to 0 when loading i915kms from console with kldload.
Blindly (or via ssh) typing intel_backlight 80 restores brightness.

Setting hw.acpi.video.lcd0.fullpower = some value in loader.conf does not help.
Comment 1 Joe Maloney 2016-08-26 14:46:29 UTC 
I can confirm this behavior when booted using BIOS mode.  VT works fine after KMS is loaded using EFI mode.  I can confirm this with nvidia-modeset, and radeomkms as well.  All work fine when using EFI.
Comment 2 Joe Maloney 2016-08-26 14:48:22 UTC 
I think this may be related to:

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=210647