Because it makes more sense there, IMHO.
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
After the register save/restore code is gone there's just one user
left and it just obfuscates that one. Remove it.
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Suggested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Burning cpu cycles isn't awesome, so use sleeps instead.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Since that's really what we want to test for. Note remove the gen5
case doesn't change anything: In intel_setup_outputs ilk is handled
already in the HAS_PCH_SPLIT case, and the register save/restore code
touches registers which simply doesn't exist anymore at all.
v2: Drop UMS parts.
v3: Update commit message to reflect that the reg save/restore code is
gone (Ville).
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Follow the correct pipe vs port disable sequence for the PCH LVDS
ports, ie. disable the port after the pipe.
Other PCH port were already converted in the following commits:
1ea56e269e drm/i915: Disable CRT port after pipe on PCH platforms
3c65d1d1bb drm/i915: Disable SDVO port after the pipe on PCH platforms
a4790cec3a drm/i915: Disable HDMI port after the pipe on PCH platforms
08aff3fe26 drm/i915: Move DP port disable to post_disable for pch platforms
but LVDS was forgotten.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
intel_atomic_setup_scalers() dereferences 'plane' before the plane has
been assigned. The plane ID assignment doing this dereference is only
needed for debugging messages later in the function, so just move the
assignment farther down the function to a point where plane will no
longer be NULL.
This was introduced in:
commit 133b0d128b
Author: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Date: Mon Jun 15 12:33:39 2015 +0200
drm/i915: Clean up intel_atomic_setup_scalers slightly.
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Bob Paauwe <bob.j.paauwe@intel.com>
Reported-by: Bob Paauwe <bob.j.paauwe@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Now when we have requests this deep on call chain, we can mark
the elsp being submitted when it actually is. Remove temp variable
and readjust commenting to more closely fit to the code.
v2: Avoid tmp variable and reduce number of writes (Chris)
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Pass around requests to carry context deeper in callchain.
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Pass around requests to carry context deeper in callchain.
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Pass around requests to carry context deeper in callchain.
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
In preparation to make intel_lr_context_pin|unpin to accept
requests, assign ringbuf into request before we call the pinning.
v2: No need to unset ringbuf on error path (Chris)
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Pass around requests to carry context deeper in callchain.
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Pass around requests to carry context deeper in callchain.
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
It is found that i915 will not reset gpu under execlist mode when
unload module. that will lead to some issues when unload/load module
with different submission mode. e.g. from execlist mode to ring
buffer mode via loading/unloading i915. Because HW is not in a reset
state and registers are not clean under such condition.
Signed-off-by: Niu,Bing <bing.niu@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
In this WA we need to set GEN8_L3SQCREG4[21:21] and reset it after PIPE_CONTROL
instruction but there is a slight complication as this is applied in WA batch
where the values are only initialized once.
Dave identified an issue with the current implementation where the register value
is read once at the beginning and it is reused; this patch corrects this by saving
the register value to memory, update register with the bit of our interest and
restore it back with original value.
This implementation uses MI_LOAD_REGISTER_MEM which is currently only used
by command parser and was using a default length of 0. This is now updated
with correct length and moved to appropriate place.
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: Arun Siluvery <arun.siluvery@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Now all the functions called by other files check whether FBC has been
initialized. This allows us to drop the checks on the static
functions.
v2:
- s/HAS_FBC/dev_priv->display.enable_fbc/ everywhere but the init
function (Chris).
Suggested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Everything is covered either by fbc.lock or mm.stolen_lock, and
intel_fbc.c is already responsible for grabbing the appropriate locks
when it needs them.
Reviewed-by: Chris wilson <chris@chris-wilson.co.uk>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
So don't grab the lock before calling the function.
Reviewed-by: Chris wilson <chris@chris-wilson.co.uk>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
So release the lock earlier.
Reviewed-by: Chris wilson <chris@chris-wilson.co.uk>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Make sure we're not going to have weird races in really weird cases
where a lot of different CRTCs are doing rendering and modesets at the
same time.
With this change and the stolen_lock from the previous patch, we can
start removing the struct_mutex locking we have around FBC in the next
patches.
v2:
- Rebase (6 months later)
- Also lock debugfs and stolen.
v3:
- Don't lock a single value read (Chris).
- Replace lockdep assertions with WARNs (Daniel).
- Improve commit message.
- Don't forget intel_pre_plane_update() locking.
v4:
- Don't remove struct_mutex at intel_pre_plane_update() (Chris).
- Add comment regarding locking dependencies (Chris).
- Rebase after the stolen code rework.
- Rebase again after drm-intel-nightly changes.
v5:
- Rebase after the new stolen_lock patch.
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> (v4)
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Which should protect dev_priv->mm.stolen usage. This will allow us to
simplify the relationship between stolen memory, FBC and struct_mutex.
v2:
- Rebase after the stolen_remove_node() dev_priv patch move.
- I realized that after we fixed a few things related to the FBC CFB
size checks, we're not reallocating the CFB anymore with FBC
enabled, so we can just move all the locking to i915_gem_stolen.c
and stop worrying about freezing all the stolen alocations while
freeing/rellocating the CFB. This allows us to fix the "Too
coarse" observation from Chris.
Suggested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
With the abstractions created by the last patch, we can move this code
and the only thing inside intel_fbc.c that knows about dev_priv->mm is
the code that reads stolen_base.
We also had to move a call to i915_gem_stolen_cleanup_compression()
- now called intel_fbc_cleanup_cfb() - outside i915_gem_stolen.c.
v2:
- Rebase after the remove_node() changes on the previous patch.
Requested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We want to move the FBC code out of i915_gem_stolen.c, but that code
directly adds/removes stolen memory nodes. Let's create this
abstraction, so i915_gme_stolen.c is still in control of all the
stolen memory handling. The abstraction will also allow us to add
locking assertions later.
v2:
- Add dev_priv as remove_node() argument since we'll need it later
(Chris).
Requested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Kill the extra intel_pre_plane_update() I accidentally added in
commit 852eb00dc4
Author: Ville Syrjälä <ville.syrjala@linux.intel.com>
Date: Wed Jun 24 22:00:07 2015 +0300
drm/i915: Try to make sure cxsr is disabled around plane
enable/disable
This fixes a load of warnings from the frontbuffer tracking.
Testcase: igt/kms_frontbuffer_tracking/fbc-1p-rte
Tested-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Tested-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Adding support for did2, or the extended support display devices ID
list, increases the total to 15.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Make it easier to handle the extended didl. No functional changes.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Conform to same style as the rest of the driver.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Inluding extended didl and cpdl fields
Present since opregion version 3.0.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Add an overview of the drm/i915 hotplug handling.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Clarify that audio enable/disable sequences are part of the modeset
sequence.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
drivers/gpu/drm/i915/intel_ddi.c: In function ‘intel_prepare_ddi’:
drivers/gpu/drm/i915/intel_ddi.c:517:6: warning:
‘ddi_translations_fdi’ may be used uninitialized in this function
[-Wmaybe-uninitialized]
if (ddi_translations_fdi)
^
drivers/gpu/drm/i915/intel_ddi.c:446:30: note: ‘ddi_translations_fdi’
was declared here
const struct ddi_buf_trans *ddi_translations_fdi;
^
This line used to be there, but was removed by:
commit f8896f5d58
Author: David Weinehall <david.weinehall@linux.intel.com>
Date: Thu Jun 25 11:11:03 2015 +030
drm/i915/skl: Buffer translation improvements
Cc: David Weinehall <david.weinehall@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Ensures that the batch buffer is executed by the resource streamer.
And will let userspace know whether Resource Streamer is supported in
the kernel.
v2: Don't skip 1<<15 for the exec flags (Jani Nikula)
v3: Use HAS_RESOURCE_STREAMER macro for execbuf validation (Chris Wilson)
(from getparam patch)
v2: Update I915_PARAM_HAS_RESOURCE_STREAMER so it's after
I915_PARAM_HAS_GPU_RESET.
v3: Only advertise RS support for hardware that supports it.
v4: Add HAS_RESOURCE_STREAMER() macro (Chris)
Testcase: igt/gem_exec_params
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Kenneth Graunke <kenneth@whitecape.org>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>
[danvet: squash in getparam patch since it'd break bisect, suggested
by Chris.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
GEN8 and above uses Execlists by default instead of the legacy
ringbuffer for batch execution. This patch enables the resource
streamer bits when required.
Patch is based on the initial work by Minu Mathai <minu.mathai@intel.com>
This version also adds the required bits to enable GEN8 Resource
Streamer context save and restore for Execlists.
Cc: ville.syrjala@linux.intel.com
Signed-off-by: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>
Reviewed-by: Arun Siluvery <arun.siluvery@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Also clarify comments on context size that the extra state for
Resource Streamer is included.
v2: Don't remove the extended save/restore enabled for older
platforms. (Ville)
Use new MI_SET_CONTEXT defines for HSW RS save/restore state
instead of extended save/restore. (Daniel)
Suggested-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Adds support for enabling the resource streamer on the legacy
ringbuffer for HSW and GEN8.
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Abdiel Janulgue <abdiel.janulgue@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This patch contains changes based on 2 updates to the spec:
Port PLL VCO restriction raised up to 6700.
Port PLL now needs DCO amp override enable for all VCO frequencies.
v2: Sonika's review comment addressed
- dcoampovr_en_h variable not required
Based on a discussion with Siva, the following changes have been made.
- replace dco_amp var with #define BXT_DCO_AMPLITUDE
- set pll10 in a single assignment
v3:
Move DCO amplitude default value to i915_reg.h. Suggested by Siva.
Signed-off-by: Vandana Kannan <vandana.kannan@intel.com>
Reviewed-by: Sonika Jindal <sonika.jindal@intel.com> [v2]
[danvet: Spell out BUN since not everyone knows what this means.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
HDMI 12bpc should be working fine now. Let it loose.
This reverts commit 5e3daaca09.
v2: Rebased due to CHV/BXT port clock check improvemnts
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-and-tested-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
CHV/BXT DPLL can't generate frequencies in the 216-240 MHz range.
Account for that when checking whether the HDMI port clock is valid.
This is particularly important for BXT since it can otherwise do
12bpc, and standard 1920x1080p60 CEA modes land right in the middle
of that range when the clock gets multiplied to account for 12bpc.
With the extra checks we will now filter out any mode where both
8bpc and 12bpc clock are within the gap. During modeset we then
pick whichever mode works, favoring 12bpc if both are possible.
12bpc isn't supported on CHV so we simply end up filtering out any
mode where the 8bpc port clock is in the gap.
v2: Fix crtc_clock vs. port_clock fumble in compute_config() (Imre)
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-and-tested-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Increase the HDMI port minimum port clock from 20 to 25 MHz. This is
is the minimum listed in the DVI/HDMI specs, and it's also the
documented minimum DPLL frequency for most of our platforms.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-and-tested-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Take the HDMI 12bpc mode and pixel repeat into account when extracting
the dotclock from the hardware on DDI platforms.
Tested on HSW only.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-and-tested-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The drm_property_unreference_blob() function tests whether its argument
is NULL and then returns immediately.
Thus the test around the call is not needed.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Reviewed-by: Zhao Junwang <zhjwpku@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Previously we have pointed the page where the individual ppgtt
scratch structures refer to, to be the instance which GGTT setup have
allocated. So it has been shared.
To achieve full isolation between ppgtts also in this regard,
allocate per ppgtt scratch page.
Cc: Michel Thierry <michel.thierry@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Michel Thierry <michel.thierry@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
On CHT, changes are required for calculating the correct m,n & p with
minimal error +/- for the required DSI clock, so that the correct
dividor & ctrl values are written in cck regs for DSI. This patch has
been tested on CHT RVP with 1200 x 1920 panel.
v2 by Jani, rebased on earlier refactoring, original at [1].
[1] http://mid.gmane.org/1431368400-1942-5-git-send-email-rodrigo.vivi@intel.com
Signed-off-by: Gaurav K Singh <gaurav.k.singh@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
For MIPI panels requiring higher DSI clk, values needs to be added
in lfsr_converts table for getting the correct values of pll ctrl
and dividor values which gets programmed in cck regs, otherwise DSI
PLL does not get locked leading to no display on the MIPI panel.
Signed-off-by: Gaurav K Singh <gaurav.k.singh@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Nuke three copies of the same switch case.
Hopefully we can switch to a drm generic function later on, but that
will require us to swich to enum mipi_dsi_pixel_format first.
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We first set the threshold value when we're allocating the CFB, and
then later at {ilk,gen7}_fbc_enable() we increment it in case we're
using 16bpp. While that is correct, it is dangerous: if we rework the
code a little bit in a way that allows us to call intel_fbc_enable()
without necessarily calling i915_gem_stolen_setup_compression() first,
we might end up incrementing threshold more than once. To prevent
that, increment a temporary variable instead.
v2: Rebase.
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Currently only normal views were accounted which under-accounts
the usage as reported in debugfs.
Introduce new helper, i915_gem_obj_total_ggtt_size, and use it
from call sites which want to know how much GGTT space are
objects using.
v2: Single loop in i915_gem_get_aperture_ioctl. (Chris Wilson)
v3: Walk GGTT active/inactive lists in i915_gem_get_aperture_ioctl
for better efficiency. (Chris Wilson, Daniel Vetter)
v4: Make i915_gem_obj_total_ggtt_size private to debugfs. (Chris Wilson)
v5: Change unsigned long to u64. (Chris Wilson)
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Every other alloc_* function return the pointer to the page
they alloc. Follow the convention with scratch page also.
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Michel Thierry <michel.thierry@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>