Fixes a regression from 9e984bc1 (drm/i915: Don't do MTRR setup if PAT
is enabled) where we left the MTRR as 0 and so tried to free a MTRR we
did not own during unload.
Reported-and-tested-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We've lost our guard page somewhere in the gtt rewrite, this patch
here will restore it.
Exercised by i-g-t/tests/gem_cs_prefetch.
v2: Substract the guard page from the range we're supposed to manage
with gem. Suggested by Chris Wilson to increase the odds of old ums +
gem userspace not blowing up. To compensate for the loss of a page,
don't substract the guard page in the modeset init code any longer.
Tested-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=44748
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
So don't call it like that.
Also rip out a confusing comment and instead explain what's really
going on.
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
... because this is what it actually doesn now that we have the global
gtt vs. ppgtt split.
Also move it to the other global gtt functions in i915_gem_gtt.c
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
On Sanybridge a few MI read/write commands only work when ppgtt is
enabled. Userspace therefore needs to be able to check whether ppgtt
is enabled. For added hilarity, you need to reset the "use global GTT"
bit on snb when ppgtt is enabled, otherwise it won't work. Despite
what bspec says about automatically using ppgtt ...
Luckily PIPE_CONTROL (the only write cmd current userspace uses) is
not affected by all this, as tested by tests/gem_pipe_control_store_loop.
Reviewed-and-tested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Use a more current logging style. Ensure that appropriate
logging messages are prefixed with "i915: ".
Convert printks to pr_<level>. Align arguments.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Some newer BIOSes are shipping with all MTRRs already populated. These
BIOSes are all on machines with sufficiently new CPUs that the
referenced errata doesn't apply anyway, so just don't try to claim the
MTRR.
Signed-off-by: Adam Jackson <ajax@redhat.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=41648
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
No functional change here, just clarifying code flow.
Signed-off-by: Adam Jackson <ajax@redhat.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Manually resolve the conflict between the new enum drm property
helpers in drm-next and the new "force-dvi" option that the "audio" output
property gained in drm-intel-next.
While resolving this conflict, switch the new drm_prop_enum_list to
use the newly introduced enum defines instead of magic values.
Conflicts:
drivers/gpu/drm/i915/intel_modes.c
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The current enabling of bus mastering in the drm midlayer allows a large
race condition under kexec. When a kexec'ed kernel re-enables bus mastering
for the GPU, previously setup dma blocks may cause writes to random pieces
of memory. On radeon the writeback mechanism can cause these sorts of issues.
This patch doesn't fix the problem, but it moves the bus master enable under
the individual drivers control so they can move enabling it until later in
their load cycle and close the race.
Fix for radeon kms driver will be in a follow-up patch.
Signed-off-by: Dave Airlie <airlied@redhat.com>
* tag 'drm-intel-next-2012-02-07' of git://people.freedesktop.org/~danvet/drm-intel: (29 commits)
drm/i915: Handle unmappable buffers during error state capture
drm/i915: rewrite shmem_pread_slow to use copy_to_user
drm/i915: rewrite shmem_pwrite_slow to use copy_from_user
drm/i915: fall through pwrite_gtt_slow to the shmem slow path
drm/i915: add debugfs file for swizzling information
drm/i915: fix swizzle detection for gen3
drm/i915: Remove the upper limit on the bo size for mapping into the CPU domain
drm/i915: add per-ring fault reg to error_state
drm/i915: reject GTT domain in relocations
drm/i915: remove the i915_batchbuffer_info debugfs file
drm/i915: capture error_state also for stuck rings
drm/i915: refactor debugfs create functions
drm/i915: refactor debugfs open function
drm/i915: don't trash the gtt when running out of fences
drm/i915: Separate fence pin counting from normal bind pin counting
drm/i915/ringbuffer: kill snb blt workaround
drm/i915: collect more per ring error state
drm/i915: refactor ring error state capture to use arrays
drm/i915: switch ring->id to be a real id
drm/i915: set AUD_CONFIG N_value_index for DisplayPort
...
The locking in our setup and teardown paths is rather arbitrary, but
generally we try to protect gem stuff with dev->struct_mutex. Further,
the ums/gem ioctl to setup gem _does_ take the look. So fix up this
benign inconsistency.
Notice while reading through code.
v2: Rebased on top of the ppgtt code.
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Back-merge from drm-fixes into drm-intel-next to sort out two things:
- interlaced support: -fixes contains a bugfix to correctly clear
interlaced configuration bits in case the bios sets up an interlaced
mode and we want to set up the progressive mode (current kernels
don't support interlaced). The actual feature work to support
interlaced depends upon (and conflicts with) this bugfix.
- forcewake voodoo to workaround missed IRQ issues: -fixes only enabled
this for ivybridge, but some recent bug reports indicate that we
need this on Sandybridge, too. But in a slightly different flavour
and with other fixes and reworks on top. Additionally there are some
forcewake cleanup patches heading to -next that would conflict with
currrent -fixes.
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We want to unconditionally enable ppgtt for two reasons:
- Windows uses this on snb and later.
- We need the basic hw support to work before we can think about real
per-process address spaces and other cool features we want.
But Chris Wilson was complaining all over irc and intel-gfx that this
will blow up if we don't have a module option to disable it. Hence add
one, to prevent this.
ppgtt support seems to slightly change the timings and make crashy
things slightly more or less crashy. Now in my testing and the testing
this got on troublesome snb machines, it seems to have improved things
only. But on ivb it makes quite a few crashes happen much more often,
see
https://bugs.freedesktop.org/show_bug.cgi?id=41353
Luckily Eugeni Dodonov seems to have a set of workarounds that fix
this issue.
v2: Don't try to enable ppgtt on pre-snb.
v3: Pimp commit message and make Chris Wilson less grumpy by adding a
module option.
v4: New try at making Chris Wilson happy.
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Reviewed-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This just adds the setup and teardown code for the ppgtt PDE and the
last-level pagetables, which are fixed for the entire lifetime, at
least for the moment.
v2: Kill the stray debug printk noted by and improve the pte
definitions as suggested by Chris Wilson.
v3: Clean up the aperture stealing code as noted by Ben Widawsky.
v4: Paint the init code in a more pleasing colour as suggest by Chris
Wilson.
v5: Explain the magic numbers noticed by Ben Widawsky.
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Tested-by: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Reviewed-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We have to do this manually. Somebody had a Great Idea.
I've measured speed-ups just a few percent above the noise level
(below 5% for the best case), but no slowdows. Chris Wilson measured
quite a bit more (10-20% above the usual snb variance) on a more
recent and better tuned version of sna, but also recorded a few
slow-downs on benchmarks know for uglier amounts of snb-induced
variance.
v2: Incorporate Ben Widawsky's preliminary review comments and
elaborate a bit about the performance impact in the changelog.
v3: Add a comment as to why we don't need to check the 3rd memory
channel.
v4: Fixup whitespace.
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
* 'for-airlied' of git://people.freedesktop.org/~danvet/drm-intel:
drm/i915: add a LLC feature flag in device description
drm/i915: kill i915_mem.c
drm/i915: Use kcalloc instead of kzalloc to allocate array
drm/i915/dp: Check for AUXCH error before checking for success
drm/i915/dp: Use auxch precharge value of 5 everywhere
drm/i915/dp: Tweak auxch clock divider for PCH
drm/i915: Remove a comment about PCH from the non-PCH path
drm/i915: Fix assert_pch_hdmi_disabled to mention HDMI (not DP)
drm/i915: Implement plane-disabled assertion for PCH too
drivers: i915: Fix BLC PWM register setup
drm/i915: Check that plane/pipe is disabled before removing the fb
drm/i915: fix typo in function name
drm/i915: split out pll divider code
drm/i915: split 9xx refclk & sdvo tv code out
agp/intel: Add pci id for hostbridge from has/qemu
drm/i915: there is no pipe CxSR on ironlake
drm/i915: Only look for matching clocks for LVDS downclock
drm/i915: Silence _DSM errors
Sometimes it may be the case when we idle the gpu or wait on something
we don't actually want to process the retiring list. This patch allows
callers to choose the behavior.
Reviewed-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The problem this patch solves is that the forcewake accounting
necessary for register reads is protected by dev->struct_mutex. But the
hangcheck and error_capture code need to access registers without
grabbing this mutex because we hold it while waiting for the gpu.
So a new lock is required. Because currently the error_state capture
is called from the error irq handler and the hangcheck code runs from
a timer, it needs to be an irqsafe spinlock (note that the registers
used by the irq handler (neglecting the error handling part) only uses
registers that don't need the forcewake dance).
We could tune this down to a normal spinlock when we rework the
error_state capture and hangcheck code to run from a workqueue. But
we don't have any read in a fastpath that needs forcewake, so I've
decided to not care much about overhead.
This prevents tests/gem_hangcheck_forcewake from i-g-t from killing my
snb on recent kernels - something must have slightly changed the
timings. On previous kernels it only trigger a WARN about the broken
locking.
v2: Drop the previous patch for the register writes.
v3: Improve the commit message per Chris Wilson's suggestions.
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
LLC is not SNB/IVB-specific, so we should check for it in a more generic
way.
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Signed-off-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Some decent history digging indicates that this was to be used for the
GLX_MESA_allocate_memory extension but never actually implemented for
any released i915 userspace code.
So just rip it out.
v2: Fixup the Makefile.
Acked-by: Dave Airlie <airlied@gmail.com>
Cc: Keith Whitwell <keithw@vmware.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
These registers are automatically incremented by the hardware during
transform feedback to track where the next streamed vertex output
should go. Unlike the previous generation, which had a packet for
setting the corresponding registers to a defined value, gen7 only has
MI_LOAD_REGISTER_IMM to do so. That's a secure packet (since it loads
an arbitrary register), so we need to do it from the kernel, and it
needs to be settable atomically with the batchbuffer execution so that
two clients doing transform feedback don't stomp on each others'
state.
Instead of building a more complicated interface involcing setting the
registers to a specific value, just set them to 0 when asked and
userland can tweak its pointers accordingly.
Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Signed-off-by: Keith Packard <keithp@keithp.com>
Add new ioctls for getting and setting the current destination color
key. This allows for simple overlay display control by matching a color
key value in the primary plane before blending the overlay on top.
v2: remove unnecessary mutex acquire/release around reg accesses
v3: add support for full color key management
v4: fix copy & paste bug in snb_get_colorkey
don't bother checking min/max values against docs as the docs are likely
wrong (how could we handle 10bpc surface formats?)
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This prevents an in-kernel division by zero which happens when we are
asking for i915_chipset_val too quickly, or within a race condition
between the power monitoring thread and userspace accesses via debugfs.
The issue can be reproduced easily via the following command:
while ``; do cat /sys/kernel/debug/dri/0/i915_emon_status; done
This is particularly dangerous because it can be triggered by
a non-privileged user by just reading the debugfs entry.
This issue was also found independently by Konstantin Belousov
<kostikbel@gmail.com>, who proposed a similar patch.
Reported-by: Konstantin Belousov <kostikbel@gmail.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Acked-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
Well almost anyway. IVB has 3 planes, pipes, transcoders, and FDI
interfaces, but only 2 pipe PLLs. So two of the pipes must use the same
pipe timings (e.g. 2 DP plus one other, or two HDMI with the same mode
and one other, etc.).
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Tested-By: Eugeni Dodonov <eugeni.dodonov@intel.com>
Reviewed-By: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
Various issues involved with the space character were generating
warnings in the checkpatch.pl file. This patch removes most of those
warnings.
Signed-off-by: Akshay Joshi <me@akshayjoshi.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
Physically-addressed hardware status pages are initialized early in
the driver load process by i915_init_phys_hws. For UMS environments,
the ring structure is not initialized until the X server starts. At
that point, the entire ring structure is re-initialized with all new
values. Any values set in the ring structure (including
ring->status_page.page_addr) will be lost when the ring is
re-initialized.
This patch moves the initialization of the status_page.page_addr value
to intel_render_ring_init_dri.
Signed-off-by: Keith Packard <keithp@keithp.com>
Cc: stable@kernel.org
i915_driver_load adds a write-combining MTRR region for the GTT
aperture to improve memory speeds through the aperture. If
i915_driver_load fails after this, it would not have cleaned up the
MTRR. This shouldn't cause any problems, except for consuming an MTRR
register. Still, it's best to clean up completely in the failure path,
which is easily done by calling mtrr_del if the mtrr was successfully
allocated.
i915_driver_load calls i915_gem_load which register
i915_gem_inactive_shrink. If i915_driver_load fails after calling
i915_gem_load, the shrinker will be left registered. When called, it
will access freed memory and crash. The fix is to unregister the shrinker in the
failure path using code duplicated from i915_driver_unload.
i915_driver_load also has some incorrect gotos in the error cleanup
paths:
* After failing to initialize the GTT (which cannot happen, btw,
intel_gtt_get returns a fixed (non-NULL) value), it tries to
free the uninitialized WC IO mapping. Fixed this by changing the
target from out_iomapfree to out_rmmap
Signed-off-by: Keith Packard <keithp@keithp.com>
Tested-by: Lin Ming <ming.m.lin@intel.com>
As the enable/disable routines will be gain additional complexity in
future patches, it is necessary that all callers do not bypass the
generic interface by calling into the chipset routines directly. to do
this we make the chipset routines static, so there is no choice.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Keith Packard <keithp@keithp.com>
This lets us make the various IRQ functions static and helps avoid
problems like the one fixed in "drm/i915: Use chipset-specific irq
installers" where one of the exported functions was called rather than
the chipset specific version.
This also fixes a UMS-mode bug -- the correct irq functions for IRL
and later chips were only getting loaded in the KMS path.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Keith Packard <keithp@keithp.com>
When auditing the locking in i915_gem.c (for a prospective change which
I then abandoned), I noticed two places where struct_mutex is not held
across GEM object manipulations that would usually require it.
Since one is in initial setup and the other in driver unload, I'm
guessing the mutex is not required for either; but post a patch in case
it is.
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Keith Packard <keithp@keithp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add new interrupt handling functions for Ivy Bridge.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
This makes the Ironlake+ code trivial and generally simplifies things.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
Set the IRQ handling functions in driver load so they'll just be used
directly, rather than branching over most of the code in the chipset
functions.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
The render P-state handling code requires reading from a GT register.
This means that FORCEWAKE must be written to, a resource which is shared
and should be protected by struct_mutex. Hence we can not manipulate
that register from within the interrupt handling and so must delegate
the task to a workqueue.
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Keith Packard <keithp@keithp.com>
If the outputs are active and continuing to access the GATT when we
teardown the PTEs, then there is a potential for us to hang the GPU.
The hang tends to be a PGTBL_ER with either an invalid host access or
an invalid display plane fetch.
v2: Reorder IRQ initialisation to defer until after GEM is setup.
Reported-by: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: Daniel Vetter <daniel.vetter@ffwll.ch> (855GM)
Tested-by: Pekka Enberg <penberg@kernel.org>
# note that this doesn't fix the underlying problem of the
PGTBL_ER and pipe underruns being reported immediately upon
init on his 965GM MacBook
Reported-and-tested-by: Rick Bramley <richard.bramley@hp.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=35635
Reported-and-tested-by: Zdenek Kabelac <zdenek.kabelac@gmail.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=36048
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Added a new function which waits for the ringbuffer space to be equal to
(total - 8). This is the empty condition of the ringbuffer, and
equivalent to head==tail.
Also modified two users of this functionality elsewhere in the code.
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
i915 calls the panic handler function on last close to reset the modes,
however this is a really bad idea for multi-gpu machines, esp shareable
gpus machines. So add a new entry point for the driver to just restore
its own fbcon mode.
v2: move code into fb helper, fix panic code to block mode change on
powered off GPUs.
[airlied: this hits drm core and I wrote it and it was reviewed on intel-gfx
so really I signed it off twice ;-).]
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Dave Airlie <airlied@redhat.com>
On a Thinkpad x61s, I noticed some memory corruption when
plugging/unplugging the external VGA connection. The symptoms are that
4 bytes at the beginning of a page get overwritten by zeroes.
The address of the corruption varies when rebooting the machine, but
stays constant while it's running (so it's possible to repeatedly write
some data and then corrupt it again by plugging the cable).
Further investigation revealed that the corrupted address is
(dev_priv->status_page_dmah->busaddr & 0xffffffff), ie. the beginning of
the hardware status page of the i965 graphics card, cut to 32 bits.
So it seems that for some memory access, the hardware uses only 32 bit
addressing. If the hardware status page is located >4GB, this
corrupts unrelated memory.
Signed-off-by: Jan Niehusmann <jan@gondor.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: stable@kernel.org
Userspace has a legitimate requirement to use a delta that points to
outside of the target bo, and so we need to enable this. (As this is an
abi break, albeit a relaxation of the current restrictions, mark the change
with a new flag.)
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
We had some conversions over to the _PIPE macros, but didn't get
everything. So hide the per-pipe regs with an _ (still used in a few
places for legacy) and add a few _PIPE based macros, then make sure
everyone uses them.
[update: remove usage of non-existent no-op macro]
[update 2: keep modesetting suspend/resume code, update to new reg names]
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
[ickle: stylistic cleanups for checkpatch and taste]
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
A lot of minor tweaks to fix the tracepoints, improve the outputting for
ftrace, and to generally make the tracepoints useful again. It is a start
and enough to begin identifying performance issues and gaps in our
coverage.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Starting with SandyBridge (though possible with earlier hacked BIOSes),
the BIOS may initialise the IGFX as secondary to a discrete GPU. Prior,
it would simply disable the integrated GPU. So we adjust our PCI class
mask to match any DISPLAY_CLASS device.
In such a configuration, the IGFX is not a primary VGA controller and
so should not take part in VGA arbitration, and the error return from
vga_client_register() is expected.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: stable@kernel.org
