This is needed when using fractional feedback dividers on some IGP
chips.
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
RN50/ES1000 is a cut-down rv100 chip used in the server market.
The 3D engine on these is either not there or unverified so refuse
any attempt to configure registers on it.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Doing this like the DDX seems like the most sure fire way to avoid
having to reinvent it slowly and painfully. At the moment we keep
getting things wrong with aper vs vram, so we know the DDX does it right.
booted on PCI r100, PCIE rv370, IGP rs400.
Signed-off-by: Dave Airlie <airlied@redhat.com>
This add support for using dma32 memory on gpus that really need it.
Currently IGPs are left without DMA32 but we might need to change
that unless we can fix rs690.
Signed-off-by: Dave Airlie <airlied@redhat.com>
For now handle it via r/g/b offsets and disallow 16 bpp modes on big endian
machines.
Signed-off-by: Michel Dänzer <daenzer@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
On powerpc, since we aren't using any hw swappers, this will
get flipped around by default in hw.
tested on a G5 + rv515.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Noticed by Rafał Miłecki on dri-devel. On r6xx/r7xx hardware, laptop
panels can be driven by KLDSCP_LVTMA or UNIPHY.
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
The line mux for the connector in the bios tables
is used for enumerating drm connectors. Since
this laptop has a quirk where the same line much is
listed for both VGA and LVDS, the connectors get
combined. Setting the line mux on LVDS to an unused
value prevents both encoders from being combined into
the same connector. This should fix bko bug 13720.
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
A bug caused a new caching state to be selected on each buffer object
validation regardless of the current caching state.
Moreover, a caching state could be selected that wasn't supported by
the memory type.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Userspace sends us a special relocation type to sync video/exa
to vlines to avoid tearing, this deals with the relocation
in the kernel, it picks the correct crtc and avoids issues
where crtcs are disabled.
This version also parses the wait until to make sure it isn't
trying to do anything evil.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Normally we are free to place VRAM where we want in the GPUs
memory address space, however on IGP chips the VRAM is actual RAM,
and no special translation or aperture is used inside the GPU MC.
So when you move the VRAM aperture away from the TOM register,
you actually move it into main memory and can trash things quite badly.
This commit makes the code respect the TOM location for MC_FB_LOCATION.
Signed-off-by: Dave Airlie <airlied@redhat.com>
The crtc and cursor offsets on the legacy chips are offset from
DISPLAY_BASE_ADDR. The code worked if display base addr was at 0,
but otherwise falls to pieces.
Signed-off-by: Dave Airlie <airlied@redhat.com>
If there is a problem then this is hiding it, we shouldn't
ever need to flush the IB. Either the buffers are:
WB - caching just works.
WC - no need to do explicit flush, the MB + readback will do it
Signed-off-by: Dave Airlie <airlied@redhat.com>
1. rv370 can accept 40-bit addresses - also at 24-bit shift not 4 bits
2. rs480 table can be in 40-bit space. - 4 bit shift for top 8 bits
3. rs480 table entries can be in 40-bit space.
Signed-off-by: Dave Airlie <airlied@redhat.com>
If the NULL test is necessary, then the dereference should be moved below
the NULL test.
The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@@
type T;
expression E;
identifier i,fld;
statement S;
@@
- T i = E->fld;
+ T i;
... when != E
when != i
if (E == NULL) S
+ i = E->fld;
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Dave Airlie <airlied@linux.ie>
via_enable_vblank wasn't setting the VBlank enable bit - instead, it
was masking out the rest of the register.
At the same time, fix via_disable_vblank to clear the VBlank enable
bit.
Signed-off-by: Dave Airlie <airlied@linux.ie>
Check kzalloc retval against NULL in drm_gem_object_alloc and bail out
appropriately.
While at it merge the fail paths and jump to them by gotos at the end
of the function.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>
Check kmalloc return value in drm_debugfs_create_files and bail out
appropriately if the pointer is NULL.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>
I discovered several bugs in the FIFO code that was recently applied.
Some of them fell into the "how did this ever work" category, since in
some cases we were using the wrong FIFO size values, and the
calculations ended up being way off.
This patch fixes all the bugs I found, and works well on my GM45, 915GM
and 855GM test machines; but as usual with these sorts of patches
broader testing is definitely requested (in particular this patch
affects 830, 845 and 865 for which I don't have test hardware).
Overall, the patch clarifies the watermark calculation function by
adding some comments and debug info, and making the variable names a
bit clearer. The "get FIFO size" portion of the code has also been
corrected, so we should be able to properly detect the FIFO allocations
for each pipe, for use in the watermark calculation.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
This motherboard thinks it has an LVDS connected, so without this
patch the screen goes blank on the connected VGA monitor. More
information (for the non-KMS case) in fd.o bug #18004.
Signed-off-by: Tormod Volden <debian.tormod@gmail.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
The 915 and 945 scanout engines can handle frame buffers up to 4096 pixels
wide. Pre-9xx hardware has an 8192 byte stride limit, and so we leave the
existing 2048 max in place.
I'm not sure why we limit the height to the same value; there's no intrinsic
hardware limit in the scanout engine.
Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
This patch refactors the existing error detection and collection code,
placing most of it in i915_handle_error(). Additionally, we introduce a
work queue for scheduling post-crash tasks such as generating a uevent.
Using the uevent facility, userspace should be able to capture a
post-mortem dump for diagnostics.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Ben Gamari <bgamari.foss@gmail.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
Vbios will set lvds register correctly based on
current algorithm for lingle/dual Channel LVDS when
system boot, so we can accept this configuration
directly, regardless of LVDS enable status.
It fixed freedesktop.org bug #22262
Signed-off-by: Florian Mickler <florian@mickler.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
IGDNG mobile chip's LVDS data block removes panel fitting
register definition. So this fixes offset for LVDS timing
block parsing. Thanks for Michael Fu to catch this.
Signed-off-by: Zhenyu Wang <zhenyu.z.wang@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
As of 52dc7d32b8, we could leave an old
linear GTT mapping in place, so that apps trying to GTT-mapped write in
tiled data wouldn't get the fence added, and garbage would get displayed.
Signed-off-by: Eric Anholt <eric@anholt.net>
As we call unmap_mapping_range() twice in identical fashion, refactor
and attempt to explain why we need to call unmap_mapping_range().
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>
In KMS mode we now use the normal mode-setting paths to set the modes
back to the current configuration, so we don't need to also run the more
limited non-KMS implementation of modesetting for resume.
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
This is seen on some G41 systems, where the BIOS will consume all but
a few KB of the aperture. This should be bad for all operating systems, as
it means that the OS can't dynamically manage memory between graphics and
the rest of the system, and OSes that did static memory management
statically add memory in addition to the BIOS allocation anyway. So, instead
of working around it, just fail out verbosely.
fd.o bug #21574
Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
On some boxes the mobile chipset is used and there is no LVDS device. In such
case we had better not initialize the LVDS output device so that one pipe can
be used for other output device. For example: E-TOP.
But unfortunately the LVDS device is still initialized on the boxes based on
mobile chipset in KMS mode. It brings that this pipe occupied by LVDS can't be
used for other output device.
After checking the acpidump we find that there is no LID device on such boxes.
In such case we can use the LID device to decide whether the LVDS device should
be initialized.
If there is no LID device, we can think that there is no LVDS device. It is
unnecessary to initialize the LVDS output device.
If there exists the LID device, it will continue the current flowchart.
Maybe on some boxes there is no LVDS device but the LID device is found. In
such case it should be added to the quirk list.
http://bugs.freedesktop.org/show_bug.cgi?id=21496http://bugs.freedesktop.org/show_bug.cgi?id=21856http://bugs.freedesktop.org/show_bug.cgi?id=21127
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
[anholt: squashed in style fixups]
Signed-off-by: Eric Anholt <eric@anholt.net>
Make this consistent with the unlock statement. Also fix a
minor typo in debugfs formatting
Signed-off-by: Ben Gamari <bgamari.foss@gmail.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
This is quite useful for verifying that objects are actually mapped when
they need to be.
Signed-off-by: Ben Gamari <bgamari.foss@gmail.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
This wasn't even used as far as I could tell and will only confuse
people (like me).
Signed-off-by: Ben Gamari <bgamari.foss@gmail.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
Usually crt mainly get modes via GPIOA ports.
However on G4X platform we need to probe possible
ports for DVI-I, which could be wired to GPIOD,
then fetch our desired EDID, i.e on DG45ID platform
we successfully fetch EDID by GPIOD port.
It fixed freedesktop.org bug #21084
Signed-off-by: Ma Ling <ling.ma@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
For some reason, the DP clocks were based off a 100MHz reference instead of
the standard 96MHz reference. This caused some DP monitors to fail to lock
to the signal.
Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
Convert many printk calls to DRM_DEBUG calls to reduce kernel log noise
for normal activities. Switch other printk calls to DRM_ERROR or DRM_INFO.
Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
We are seeing compilation failures on i386 in some environments due
to an undefined reference as below:
ERROR: "__udivdi3" [drivers/gpu/drm/i915/i915.ko] undefined!
This is generated due to a raw 64 bit divide in the i915 driver. Fix up
this raw divide.
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Currently we implemented basic sdvo lvds function,
But except for sdvo lvds fixed mode, we can not switch
to other modes, otherwise display get black. The patch
handle three operations to enable sdvo lvds. At first
duplicate sdvo fixed mode for adjustment, then according
to fixed mode line valid all modes, at last adjust input
mode to fit our requirement.
Acked by Li Peng <peng.li@linux.intel.com>
Signed-off-by: Ma Ling <ling.ma@intel.com>
Reviewed-by: Ian Romanick <idr@freedesktop.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
All 8xx class chips have the 66/48 split, not just 855.
Signed-off-by: Ma Ling <ling.ma@intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
This patch from jbarnes and myself adds FIFO watermark control to the
driver. This is needed for both power saving features on new platforms
with the so-called "big FIFO" and for controlling FIFO allocation
between pipes in multi-head configurations.
It's also necessary infrastructure to support things like framebuffer
compression and configuration supportability checks (i.e. checking a
configuration against available bandwidth).
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
This patch enables error detection by enabling several types of error
interrupts. When an error interrupt is received, the interrupt
handler captures the error state; hopefully resulting in an accurate
set of error data (error type, active head pointer, etc.). The new
record is then available from sysfs. The current code will also dump
the error state to the system log.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
* 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6: (28 commits)
drm: remove unused #include <linux/version.h>'s
drm/radeon: fix driver initialization order so radeon kms can be builtin
drm: Fix shifts which were miscalculated when converting from bitfields.
drm/radeon: Clear surface registers at initialization time.
drm/radeon: Don't initialize acceleration related fields of struct fb_info.
drm/radeon: fix radeon kms framebuffer device
drm/i915: initialize fence registers to zero when loading GEM
drm/i915: Fix HDMI regression introduced in new chipset support
drm/i915: fix LFP data fetch
drm/i915: set TV detection mode when tv is already connected
drm/i915: Catch up to obj_priv->page_list rename in disabled debug code.
drm/i915: Fix size_t handling in off-by-default debug printfs
drm/i915: Don't change the blank/sync width when calculating scaled modes
drm/i915: Add support for changing LVDS panel fitting using an output property.
drm/i915: correct suspend/resume ordering
drm/i915: Add missing dependency on Intel AGP support.
drm/i915: Generate 2MHz clock for display port aux channel I/O. Retry I/O.
drm/i915: Clarify error returns from display port aux channel I/O
drm/i915: Add CLKCFG register definition
drm/i915: Split array of DAC limits into separate structures.
...
TTM need to be initialized before radeon if KMS is enabled otherwise
the kernel will crash hard.
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>
Looks like I managed to mess up most shifts when converting from bitfields. :(
The patch below works on my Thinkpad T500 (as well as on my PowerBook,
where the previous change worked as well, maybe out of luck...). I'd
appreciate more testing and eyes looking over it though.
Signed-off-by: Michel Dänzer <daenzer@vmware.com>
Tested-by: Michael Pyne <mpyne@kde.org>
Signed-off-by: Dave Airlie <airlied@linux.ie>
Some PowerMac firmwares set up a tiling surface at the beginning of VRAM
which messes us up otherwise.
Signed-off-by: Michel Dänzer <daenzer@vmware.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>
Might lure userspace into trying silly things otherwise.
Signed-off-by: Michel Dänzer <daenzer@vmware.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>
smem.start is a physical address which kernel can remap to access
video memory of the fb buffer. We now pin the fb buffer into vram
by doing so we are loosing vram but fbdev need to be reworked to
allow change in framebuffer address.
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>
Sometimes both acpi video and i915 driver are compiled as modules.
And there exists the strict dependency between the two drivers.
The acpi video bus will be unloaded in course of unloading the i915 driver.
If we unload the acpi video driver, then the kernel oops will be triggered.
Add the reference count to avoid unloading the ACPI video bus twice.
The reference count should be checked before unregistering the acpi video bus.
If the reference count is already zero, it won't unregister it again.
And after the acpi video bus is already unregistered, the reference count
will be set to zero.
http://bugzilla.kernel.org/show_bug.cgi?id=13396
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Unitialized fence register could leads to corrupted display. Problem
encountered on MacBooks (revision 1 and 2), directly booting from EFI
or through BIOS emulation.
(bug #21710 at freedestop.org)
Signed-off-by: Grégoire Henry <henry@pps.jussieu.fr>
Signed-off-by: Eric Anholt <eric@anholt.net>
Remove wrongly added NULL_PACKETS_DURING_VSYNC setting for HDMI.
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
Apparently the proper way to do this is to use the LFP data pointer
block to figure out the LFP data block entry size, then use that plus
the panel index to calculate an offset into the LFP data block array.
Similar fix has already been pushed to the 2D driver to fix fdo bug
applied to the VBIOS reader, and things look sane).
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
We used load_detect_temp flag to determine whether to set tv to the test
mode. However if the TV already has a mode set, we still need to set the
test mode to determine connection. This results in blinking, but there is
no other reliable way to determine TV connection.
freedesktop.org bug #22035
Signed-off-by: Ma Ling <ling.ma@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
Also, use the border instead of border minus one.
At the same time, make sure the horizontal border and hsync are even for
the LVDS that works in dual-channel mode. So both horizontal border and hsync
start are also changed to be even, even for the LVDS in single-channel mode.
https://bugs.freedesktop.org/show_bug.cgi?id=20951
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
Previously the driver would always scale the chosen video mode to fill the
panel. This adds 1:1 and maintain-aspect-ratio scaling modes.
v2: the drm_calloc/drm_free is replaced by kzalloc/kfree based
on Eric's suggestion.
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
We need to save register state *after* idling GEM, clearing the ring,
and uninstalling the IRQ handler, or we might end up saving bogus
fence regs, for one. Our restore ordering should already be correct,
since we do GEM, ring and IRQ init after restoring the last register
state, which prevents us from clobbering things.
I put this together to potentially address a bug, but I haven't heard
back if it fixes it yet. However I think it stands on its own, so I'm
sending it in.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Users could accidentally enable AGP but not the Intel AGP support, and get
a DRM that doesn't probe as a result.
Bug #22358.
Signed-off-by: Eric Anholt <eric@anholt.net>
In theory now that the AGP subsystem is using struct page, we should
have on problems enabling GEM on PAE systems.
Signed-off-by: Dave Airlie <airlied@redhat.com>
This switches AGP to use an array of pages for tracking the
pages allocated to the GART. This should enable GEM on PAE to work
a lot better as we can pass highmem pages to the PAT code and it will
do the right thing with them.
Signed-off-by: Dave Airlie <airlied@redhat.com>
For security purpose we want to make sure the userspace process doesn't
access memory beyond buffer it owns. To achieve this we need to check
states the userspace program. For color buffer and zbuffer we check that
the clipping register will discard access beyond buffers set as color
or zbuffer. For vertex buffer we check that no vertex fetch will happen
beyond buffer end. For texture we check various texture states (number
of mipmap level, texture size, texture depth, ...) to compute the amount
of memory the texture fetcher might access.
The command stream checking impact the performances so far quick benchmark
shows an average of 3% decrease in fps of various applications. It can
be optimized a bit more by caching result of checking and thus avoid a
full recheck if no states changed since last check.
Note that this patch is still incomplete on checking side as it doesn't
check 2d rendering states.
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
also for the atomic path by using a common code-path.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
A bug caused the ttm code to just terminate the wait when a signal
was received while waiting for the GPU to release a buffer object that
was to be evicted.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
The display port aux channel clock is taken from the hrawclk value, which is
provided to the chip as the FSB frequency (as far as I can determine). The
strapping values for that are available in the CLKCFG register, now used to
select an appropriate divider to generate a 2MHz clock.
In addition, the DisplayPort spec requires that each aux channel I/O be
retried 'at least 3 times' in case the sink is idle when the first request
comes in.
Signed-off-by: Keith Packard <keithp@keithp.com>
The array of DAC limits was only ever referenced with #defined constant
offsets, and keeping those #define values in sync with the array itself was a
nuisance. This will make future changes to the set of DAC limits less
error-prone.
Signed-off-by: Keith Packard <keithp@keithp.com>
Eliminate the copy of i2c_bus in sdvo_priv.
Eliminate local copies of i2c_bus and ddcbus.
Eliminate unused settings of slave_addr.
Signed-off-by: Keith Packard <keithp@keithp.com>
The existing API passed around intel_i2c_chan pointers, which are dependent
on the i2c bit-banging algo. This precluded the driver from using outputs
which use a different algo. Switching to the more general i2c_adpater allows
the driver to support non bit-banging DDC.
This also required moving the slave address into the output private
structures.
Signed-off-by: Keith Packard <keithp@keithp.com>
Some machines say 'Apple Inc.' while others say 'Apple Computer, Inc'.
Switch the test to just look for 'Apple' instead.
Signed-off-by: Keith Packard <keithp@keithp.com>
HDMI and DVI both require DDC/EDID on monitors, so use
that to know when a monitor is connected as the hot-plug
pins are shared with SDVO and DisplayPort
Signed-off-by: Keith Packard <keithp@keithp.com>
It hasn't been used in ages, and having the user tell your how much
memory is being freed at free time is a recipe for disaster even if it
was ever used.
Signed-off-by: Eric Anholt <eric@anholt.net>
The fence register value also depends upon the stride of the object, so we
need to clear the fence if that is changed as well.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
[anholt: Added 8xx and 965 paths, and renamed the confusing
i915_gem_object_tiling_ok function to i915_gem_object_fence_offset_ok]
Signed-off-by: Eric Anholt <eric@anholt.net>
With the work by Jesse Barnes to eliminate allocation of fences during
execbuffer, it becomes possible to write to the scan-out buffer with it
never acquiring a fence (simply by only ever writing to the object using
tiled GPU commands and never writing to it via the GTT). So for pre-i965
chipsets which require fenced access for tiled scan-out buffers, we need
to obtain a fence register.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Eric Anholt <eric@anholt.net>
After performing an operation over the page list for a buffer retrieved by
i915_gem_object_get_pages() the pages need to be returned with
i915_gem_object_put_pages(). This was not being observed for the phys
objects which were thus leaking references to their backing pages.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
CC: Dave Airlie <airlied@gmail.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
