linux/drivers/gpu
Bruno Prémont ce027dac59 vgaarb: Don't default exclusively to first video device with mem+io
commit 86fd887b7f upstream.

Commit 20cde69402 ("x86, ia64: Move EFI_FB vga_default_device()
initialization to pci_vga_fixup()") moved boot video device detection from
efifb to x86 and ia64 pci/fixup.c.

For dual-GPU Apple computers above change represents a regression as code
in efifb did forcefully override vga_default_device while the merge did not
(vgaarb happens prior to PCI fixup).

To improve on initial device selection by vgaarb (it cannot know if PCI
device not behind bridges see/decode legacy VGA I/O or not), move the
screen_info based check from pci_video_fixup() to vgaarb's init function and
use it to refine/override decision taken while adding the individual PCI
VGA devices.  This way PCI fixup has no reason to adjust vga_default_device
anymore but can depend on its value for flagging shadowed VBIOS.

This has the nice benefit of removing duplicated code but does introduce a
#if defined() block in vgaarb.  Not all architectures have screen_info and
would cause compile to fail without it.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=84461
Reported-and-Tested-By: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Bruno Prémont <bonbons@linux-vserver.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Matthew Garrett <matthew.garrett@nebula.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
History 2014-10-09 12:23:49 -07:00
..
drm drm/i915: Flush the PTEs after updating them before suspend 2014-10-09 12:23:48 -07:00
host1x gpu: host1x: Rename internal functions for clarity 2014-06-05 23:10:30 +02:00
ipu-v3 Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2014-06-12 11:32:30 -07:00
vga vgaarb: Don't default exclusively to first video device with mem+io 2014-10-09 12:23:49 -07:00
Makefile gpu: ipu-v3: Move i.MX IPUv3 core driver out of staging 2014-06-04 11:06:52 +02:00