Repository files (latest commit first)

Filename	Latest commit message	Latest commit date
Jani Nikula c6cd2ee2d5 drm/i915/dp: workaround BIOS eDP bpp clamping issue ... This isn't a real fix to the problem, but rather a stopgap measure while trying to find a proper solution. There are several laptops out there that fail to light up the eDP panel in UEFI boot mode. They seem to be mostly IVB machines, including but apparently not limited to Dell XPS 13, Asus TX300, Asus UX31A, Asus UX32VD, Acer Aspire S7. They seem to work in CSM or legacy boot. The difference between UEFI and CSM is that the BIOS provides a different VBT to the kernel. The UEFI VBT typically specifies 18 bpp and 1.62 GHz link for eDP, while CSM VBT has 24 bpp and 2.7 GHz link. We end up clamping to 18 bpp in UEFI mode, which we can fit in the 1.62 Ghz link, and for reasons yet unknown fail to light up the panel. Dithering from 24 to 18 bpp itself seems to work; if we use 18 bpp with 2.7 GHz link, the eDP panel lights up. So essentially this is a link speed issue, and *not* a bpp clamping issue. The bug raised its head since commit 657445fe86 Author: Daniel Vetter <daniel.vetter@ffwll.ch> Date: Sat May 4 10:09:18 2013 +0200 Revert "drm/i915: revert eDP bpp clamping code changes" which started clamping bpp *before* computing the link requirements, and thus affecting the required bandwidth. Clamping after the computations kept the link at 2.7 GHz. Even though the BIOS tells us to use 18 bpp through the VBT, it happily boots up at 24 bpp and 2.7 GHz itself! Use this information to selectively ignore the VBT provided value. We can't ignore the VBT eDP bpp altogether, as there are other laptops that do require the clamping to be used due to EDID reporting higher bpp than the panel can support. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=59841 Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=67950 Tested-by: Ulf Winkelvos <ulf@winkelvos.de> Tested-by: jkp <jkp@iki.fi> CC: stable@vger.kernel.org Signed-off-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>		2013-10-28 17:48:30 +01:00
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drm	drm/i915/dp: workaround BIOS eDP bpp clamping issue	2013-10-28 17:48:30 +01:00
host1x	Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux	2013-09-05 10:17:26 -07:00
vga	vgaarb: Fix VGA decodes changes	2013-09-03 19:17:59 +02:00
Makefile