We want to keep ucode xfer functions separate from other
initialization. Once separated, add explicit forcewake.

v2: use BLITTER domain only and add comment (Daniele)
Suggested-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NMichal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> #1
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171016144724.17244-3-michal.wajdeczko@intel.com

Function intel_guc_wopcm_size didn't fit well in the old place.
With this move upcoming cleanup will be simpler.
Suggested-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NMichal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171016144724.17244-2-michal.wajdeczko@intel.com

Let GVT-g VM read the CSB and CSB write pointer from virtual HWSP, not all
the host support this feature, need to check the BIT(3) of caps in PVINFO.

v3 : Remove unnecessary comments.
v4 : Separate VM enable patch with GVT-g implementation patch due to code
dependency.
v5 : Use inline for GVT virtual HWSP caps check function.
v6 : Comments refine.
Signed-off-by: NWeinan Li <weinan.z.li@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1508039725-1066-1-git-send-email-weinan.z.li@intel.com

The compiler warns:

	drivers/gpu/drm/i915/intel_ddi.c:118:35: warning: ‘bdw_ddi_translations_fdi’ defined but not used

Lo and behold, if we look at intel_ddi_get_buf_trans_fdi(), it uses
hsw_ddi_translations_fdi[] for both Haswell and *Broadwell*

Fixes: 7d1c42e6 ("drm/i915: Refactor code to select the DDI buf translation table")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: David Weinehall <david.weinehall@linux.intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: <stable@vger.kernel.org> # v4.12+
Link: https://patchwork.freedesktop.org/patch/msgid/20171013154735.27163-1-chris@chris-wilson.co.ukReviewed-by: NJani Nikula <jani.nikula@linux.intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>

Always try to stop the rings, even if the GPU reset itself has been
disabled (via modparam i915.reset). This should at least stop the hw
from spinning in the background consuming resources (e.g. power and
memory bandwidth) letting the system rest-in-peace.

References: https://bugs.freedesktop.org/show_bug.cgi?id=103260Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171013131218.18013-2-chris@chris-wilson.co.ukReviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>

Before modifying the ring register (RING_START, HEAD, TAIL, CTL) we
first make sure it is stopped (or else the hw may not resample the
registers). However, we do not need to let the hw restart until after we
have reprogrammed all the rings. This should help prevent situations
where pending operations on the ring may resume (because we are trying
to re-initialize following an unsuccessful GPU hang, i.e. from
i915_gem_unset_wedged).

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=103260Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171013131218.18013-1-chris@chris-wilson.co.ukReviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>

Since the removal of the stop_machine(), it is allowed and expected for
the nop_submit_request() and nop_complete_submit_request() to run in
parallel to the i915_gem_set_wedged() processing. As such we can no
longer assert that i915_gem_set_wedged() has completed inside the
stop_machine prior to the individual nop_submit_request execution.

Fixes: af7a8ffa ("drm/i915: Use rcu instead of stop_machine in set_wedged")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171012204019.3557-1-chris@chris-wilson.co.ukReviewed-by: NDaniel Vetter <daniel.vetter@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>

Untangle intel_enable_ddi() by splitting it into DP and HDMI specific
variants.

v2: Keep using intel_ddi_get_encoder_port() for now
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171010121207.570-10-ville.syrjala@linux.intel.comReviewed-by: NJani Nikula <jani.nikula@intel.com>

Rather that plumb the link parameters separately to
intel_ddi_pre_enable_dp() let's just pass the entire crtc state.

intel_ddi_pre_enable_hdmi() already took the crtc state, but for some
reason intel_ddi_pre_enable() still wanted to extract has_infoframe
from therein and pass it in separately. Let's not do that since it's
pointless.

v2: Rebase due to more code getting pulled into the DDI hooks

Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171010121207.570-9-ville.syrjala@linux.intel.comReviewed-by: NJani Nikula <jani.nikula@intel.com>

Untangle intel_disable_ddi() by splitting it into DP and HDMI specific
variants.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171010121207.570-8-ville.syrjala@linux.intel.comReviewed-by: NJani Nikula <jani.nikula@intel.com>

intel_edp_panel_on() will itself do the is_edp() check, so the caller
doesn't have to bother. Pre-DDI code doesn't bother, so let's follow the
same approach for DDI.
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171010121207.570-7-ville.syrjala@linux.intel.com

To clean up the mess in intel_ddi_post_disable() split it into two
clean variants for HDMI and DP.

v2: Rebase due to MST DPMS changes

Reviewed-by: Jani Nikula <jani.nikula@intel.com> #v1
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171010121207.570-6-ville.syrjala@linux.intel.com

To untangle the mess that is intel_ddi_post_disable() move the the bits
needed by FDI into intel_ddi_fdi_post_disable(). This way we can stop
worrying about FDI in intel_ddi_post_disable().
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171010121207.570-5-ville.syrjala@linux.intel.com

Extract the code to disable the DDI_BUF_CTL into small helper. This
will allows us to detangle the encoder type mess in
intel_ddi_post_disable().

v2: Keep using intel_ddi_get_encoder_port() for now
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171010121207.570-4-ville.syrjala@linux.intel.com

Pull the code to disable the port clock into a function. We already have
the intel_ddi_clk_select() counterpart.

v2: Keep using intel_ddi_get_encoder_port() for now (Chris)

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171010121207.570-3-ville.syrjala@linux.intel.comReviewed-by: NJani Nikula <jani.nikula@intel.com>

To make it easier to debug things let's dump the output types bitmask in
the crtc state dump. And to make life that much better, let's pretty
print it as a a human reaadable string as well.

v2: Have the caller pass in the buffer (Chris)
    #undef OUTPUT_TYPE (Jani)

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171010121207.570-2-ville.syrjala@linux.intel.comReviewed-by: NJani Nikula <jani.nikula@intel.com>

Replace instances of drm_framebuffer_reference/unreference() with
*_get/put() suffixes and drm_dev_unref with *_put() suffix
because get/put is shorter and consistent with the
kernel use of *_get/put suffixes.
Done with following coccinelle semantic patch

@@
expression ex;
@@

(
-drm_framebuffer_unreference(ex);
+drm_framebuffer_put(ex);
|
-drm_dev_unref(ex);
+drm_dev_put(ex);
|
-drm_framebuffer_reference(ex);
+drm_framebuffer_get(ex);
)
Signed-off-by: NHarsha Sharma <harshasharmaiitr@gmail.com>
[danvet: Drop the drm_dev_put change for now, to make the patch apply
with out a backmerge.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20171009120643.11953-1-harshasharmaiitr@gmail.com

Favor for_each_pipe() macro when looping through pipes.
Signed-off-by: NMika Kahola <mika.kahola@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1507890286-16214-1-git-send-email-mika.kahola@intel.comSigned-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>

We read the dp dual mode Adapter identifier to detect the
LSPCON device. It's been observed from the CI testing that in
few cases, this read can get delayed or fail. For such scenarios,
LSPCON vendors suggest to retry the read operation.

This patch adds retry in the probe function, while reading
LSPCON identifier.

V3: added this patch in the series

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=102294
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=102295
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=102359
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=103186
Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: NShashank Sharma <shashank.sharma@intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1507630064-17908-4-git-send-email-shashank.sharma@intel.com

Our current logic to read LSPCON's current mode, stops retries and
breaks wait-loop, if it gets LSPCON_MODE_INVALID as return from the
core function. This doesn't allow us to try reading the mode again.

This patch removes this condition and allows retries reading
the currnt mode until timeout.

This also fixes/prevents some of the noise in form of debug messages
while running IGT CI test cases.

V2: rebase, added r-b
V2: changed some debug message levels from debug->error and
    error->debug in lspcon_get_current_mode function.
V3: Rebase

Cc: Imre Deak <imre.deak@intel.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=102294
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=102295
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=102359
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=103186Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NShashank Sharma <shashank.sharma@intel.com>
Signed-off-by: NMahesh Kumar <Mahesh1.kumar@intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1507630064-17908-3-git-send-email-shashank.sharma@intel.com

From the CI builds, its been observed that during a driver
reload/insert, dp dual mode read function sometimes fails to
read from LSPCON device over i2c-over-aux channel.

This patch:
- adds some delay and few retries, allowing a scope for these
  devices to settle down and respond.
- changes one error log's level from ERROR->DEBUG as we want
  to call it an error only after all the retries are exhausted.

V2: Addressed review comments from Jani (for loop for retry)
V3: Addressed review comments from Imre (break on partial read too)
V3: Addressed review comments from Ville/Imre (Add the retries
    exclusively for LSPCON, not for all dp_dual_mode devices)
V4: Added r-b from Imre, sending it to dri-devel (Jani)

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=102294
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=102295
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=102359
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=103186
Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Acked-by: NDave Airlie <airlied@gmail.com>
Signed-off-by: NShashank Sharma <shashank.sharma@intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1507826408-19322-1-git-send-email-shashank.sharma@intel.com

Per BSpec, 400us is "BDW+ Do not use this setting." - not just PORT_A.
Set BDW to 600us unconditionally.

v2:
-Split in to two patches (Rodrigo)

Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NJames Ausmus <james.ausmus@intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171012213037.4245-2-james.ausmus@intel.com

Rename DP_AUX_CH_CTL_TIME_OUT_1600us to DP_AUX_CH_CTL_TIME_OUT_MAX, as
the meaning of the (3 << 26) value varies per platform, but it's always the
maximum timeout for that platform. Pre-CNL it means 1600us, and for CNL
it means 3200us.

v2:
-Split in to two patches (Rodrigo)

Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NJames Ausmus <james.ausmus@intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171012213037.4245-1-james.ausmus@intel.com

A bug recently encountered involved the issue where are we were
submitting requests to different ppGTT, each would pin a segment of the
GGTT for its logical context and ring. However, this is invisible to
eviction as we do not tie the context/ring VMA to a request and so do
not automatically wait upon it them (instead they are marked as pinned,
preventing eviction entirely). Instead the eviction code must flush those
contexts by switching to the kernel context. This selftest tries to
fill the GGTT with contexts to exercise a path where the
switch-to-kernel-context failed to make forward progress and we fail
with ENOSPC.

v2: Make the hole in the filled GGTT explicit.
v3: Swap out the arbitrary timeout for a private notification from
i915_gem_evict_something()
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171012125726.14736-3-chris@chris-wilson.co.ukReviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>

For some selftests, we want to issue requests but delay them going to
hardware. Furthermore, we don't want those requests to block
indefinitely (or else we may hang the driver and block testing) so we
want to employ a timeout. So naturally we want a fence that is
automatically signaled by a timer.

v2: Add kselftests.
v3: Limit the API available to selftests; there isn't an overwhelming
reason to export it universally.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171012125726.14736-2-chris@chris-wilson.co.ukReviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>

In the full-ppgtt world, we can fill the GGTT full of context objects.
These context objects are currently implicitly tracked by the requests
that pin them i.e. they are only unpinned when the request is completed
and retired, but we do not have the link from the vma to the request
(anymore). In order to unpin those contexts, we have to issue another
request and wait upon the switch to the kernel context.

The bug during eviction was that we assumed that a full GGTT meant we
would have requests on the GGTT timeline, and so we missed situations
where those requests where merely in flight (and when even they have not
yet been submitted to hw yet). The fix employed here is to change the
already-is-idle test to no look at the execution timeline, but count the
outstanding requests and then check that we have switched to the kernel
context. Erring on the side of overkill here just means that we stall a
little longer than may be strictly required, but we only expect to hit
this path in extreme corner cases where returning an erroneous error is
worse than the delay.

v2: Logical inversion when swapping over branches.

Fixes: 80b204bc ("drm/i915: Enable multiple timelines")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171012125726.14736-1-chris@chris-wilson.co.uk

Add the minimal amount of PSR tracking into the crtc state. This allows
precomputing the possibility of using PSR correctly, and it means we can
safely call the psr enable/disable functions for any DP endcoder.

As a nice bonus we get rid of some more crtc->config usage, which we
want to kill off eventually.

v2: Fix 'goto unlock' fail in intel_psr_enable() (Jani)
    Check intel_dp_is_edp() in is_edp_psr() (Jani)

Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171012130201.21318-1-ville.syrjala@linux.intel.comReviewed-by: NJani Nikula <jani.nikula@intel.com>
Acked-by: NRodrigo Vivi <rodrigo.vivi@intel.com>

Signed-off-by: NJani Nikula <jani.nikula@intel.com>

Remove dead code around has_aliasing_ppgtt condition.
Suggested-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171010143355.16577-1-joonas.lahtinen@linux.intel.com

Purely to silence lockdep, as we know that no bo can exist at this time
and so the inversion is impossible. Nevertheless, lockdep currently
warns on unload:

[  137.522565] WARNING: possible circular locking dependency detected
[  137.522568] 4.14.0-rc4-CI-CI_DRM_3209+ #1 Tainted: G     U
[  137.522570] ------------------------------------------------------
[  137.522572] drv_module_relo/1532 is trying to acquire lock:
[  137.522574]  ("i915-userptr-acquire"){+.+.}, at: [<ffffffff8109a831>] flush_workqueue+0x91/0x540
[  137.522581]
               but task is already holding lock:
[  137.522583]  (&dev->struct_mutex){+.+.}, at: [<ffffffffa014fb3f>] i915_gem_fini+0x3f/0xc0 [i915]
[  137.522605]
               which lock already depends on the new lock.

[  137.522608]
               the existing dependency chain (in reverse order) is:
[  137.522611]
               -> #3 (&dev->struct_mutex){+.+.}:
[  137.522615]        __lock_acquire+0x1420/0x15e0
[  137.522618]        lock_acquire+0xb0/0x200
[  137.522621]        __mutex_lock+0x86/0x9b0
[  137.522623]        mutex_lock_interruptible_nested+0x1b/0x20
[  137.522640]        i915_mutex_lock_interruptible+0x51/0x130 [i915]
[  137.522657]        i915_gem_fault+0x20b/0x720 [i915]
[  137.522660]        __do_fault+0x1e/0x80
[  137.522662]        __handle_mm_fault+0xa08/0xed0
[  137.522664]        handle_mm_fault+0x156/0x300
[  137.522666]        __do_page_fault+0x2c5/0x570
[  137.522668]        do_page_fault+0x28/0x250
[  137.522671]        page_fault+0x22/0x30
[  137.522672]
               -> #2 (&mm->mmap_sem){++++}:
[  137.522677]        __lock_acquire+0x1420/0x15e0
[  137.522679]        lock_acquire+0xb0/0x200
[  137.522682]        down_read+0x3e/0x70
[  137.522699]        __i915_gem_userptr_get_pages_worker+0x141/0x240 [i915]
[  137.522701]        process_one_work+0x233/0x660
[  137.522704]        worker_thread+0x4e/0x3b0
[  137.522706]        kthread+0x152/0x190
[  137.522708]        ret_from_fork+0x27/0x40
[  137.522710]
               -> #1 ((&work->work)){+.+.}:
[  137.522714]        __lock_acquire+0x1420/0x15e0
[  137.522717]        lock_acquire+0xb0/0x200
[  137.522719]        process_one_work+0x206/0x660
[  137.522721]        worker_thread+0x4e/0x3b0
[  137.522723]        kthread+0x152/0x190
[  137.522725]        ret_from_fork+0x27/0x40
[  137.522727]
               -> #0 ("i915-userptr-acquire"){+.+.}:
[  137.522731]        check_prev_add+0x430/0x840
[  137.522733]        __lock_acquire+0x1420/0x15e0
[  137.522735]        lock_acquire+0xb0/0x200
[  137.522738]        flush_workqueue+0xb4/0x540
[  137.522740]        drain_workqueue+0xd4/0x1b0
[  137.522742]        destroy_workqueue+0x1c/0x200
[  137.522758]        i915_gem_cleanup_userptr+0x15/0x20 [i915]
[  137.522770]        i915_gem_fini+0x5f/0xc0 [i915]
[  137.522782]        i915_driver_unload+0x122/0x180 [i915]
[  137.522794]        i915_pci_remove+0x19/0x30 [i915]
[  137.522797]        pci_device_remove+0x39/0xb0
[  137.522800]        device_release_driver_internal+0x15d/0x220
[  137.522803]        driver_detach+0x40/0x80
[  137.522805]        bus_remove_driver+0x58/0xd0
[  137.522807]        driver_unregister+0x2c/0x40
[  137.522809]        pci_unregister_driver+0x36/0xb0
[  137.522828]        i915_exit+0x1a/0x8b [i915]
[  137.522831]        SyS_delete_module+0x18c/0x1e0
[  137.522834]        entry_SYSCALL_64_fastpath+0x1c/0xb1
[  137.522835]
               other info that might help us debug this:

[  137.522838] Chain exists of:
                 "i915-userptr-acquire" --> &mm->mmap_sem --> &dev->struct_mutex

[  137.522844]  Possible unsafe locking scenario:

[  137.522846]        CPU0                    CPU1
[  137.522848]        ----                    ----
[  137.522850]   lock(&dev->struct_mutex);
[  137.522852]                                lock(&mm->mmap_sem);
[  137.522854]                                lock(&dev->struct_mutex);
[  137.522857]   lock("i915-userptr-acquire");
[  137.522859]
                *** DEADLOCK ***

[  137.522862] 3 locks held by drv_module_relo/1532:
[  137.522864]  #0:  (&dev->mutex){....}, at: [<ffffffff8161d47b>] device_release_driver_internal+0x2b/0x220
[  137.522869]  #1:  (&dev->mutex){....}, at: [<ffffffff8161d489>] device_release_driver_internal+0x39/0x220
[  137.522873]  #2:  (&dev->struct_mutex){+.+.}, at: [<ffffffffa014fb3f>] i915_gem_fini+0x3f/0xc0 [i915]
[  137.522888]
               stack backtrace:
[  137.522891] CPU: 0 PID: 1532 Comm: drv_module_relo Tainted: G     U          4.14.0-rc4-CI-CI_DRM_3209+ #1
[  137.522894] Hardware name:                  /NUC7i5BNB, BIOS BNKBL357.86A.0048.2017.0704.1415 07/04/2017
[  137.522897] Call Trace:
[  137.522900]  dump_stack+0x68/0x9f
[  137.522902]  print_circular_bug+0x235/0x3c0
[  137.522905]  ? lockdep_init_map_crosslock+0x20/0x20
[  137.522908]  check_prev_add+0x430/0x840
[  137.522919]  ? i915_gem_fini+0x5f/0xc0 [i915]
[  137.522922]  ? __kernel_text_address+0x12/0x40
[  137.522925]  ? __save_stack_trace+0x66/0xd0
[  137.522928]  __lock_acquire+0x1420/0x15e0
[  137.522930]  ? __lock_acquire+0x1420/0x15e0
[  137.522933]  ? lockdep_init_map_crosslock+0x20/0x20
[  137.522936]  ? __this_cpu_preempt_check+0x13/0x20
[  137.522938]  lock_acquire+0xb0/0x200
[  137.522940]  ? flush_workqueue+0x91/0x540
[  137.522943]  flush_workqueue+0xb4/0x540
[  137.522945]  ? flush_workqueue+0x91/0x540
[  137.522948]  ? __mutex_unlock_slowpath+0x43/0x2c0
[  137.522951]  ? trace_hardirqs_on_caller+0xe3/0x1b0
[  137.522954]  drain_workqueue+0xd4/0x1b0
[  137.522956]  ? drain_workqueue+0xd4/0x1b0
[  137.522958]  destroy_workqueue+0x1c/0x200
[  137.522975]  i915_gem_cleanup_userptr+0x15/0x20 [i915]
[  137.522987]  i915_gem_fini+0x5f/0xc0 [i915]
[  137.523000]  i915_driver_unload+0x122/0x180 [i915]
[  137.523015]  i915_pci_remove+0x19/0x30 [i915]
[  137.523018]  pci_device_remove+0x39/0xb0
[  137.523021]  device_release_driver_internal+0x15d/0x220
[  137.523023]  driver_detach+0x40/0x80
[  137.523026]  bus_remove_driver+0x58/0xd0
[  137.523028]  driver_unregister+0x2c/0x40
[  137.523030]  pci_unregister_driver+0x36/0xb0
[  137.523049]  i915_exit+0x1a/0x8b [i915]
[  137.523052]  SyS_delete_module+0x18c/0x1e0
[  137.523055]  entry_SYSCALL_64_fastpath+0x1c/0xb1
[  137.523057] RIP: 0033:0x7f7bd0609287
[  137.523059] RSP: 002b:00007ffef694bc18 EFLAGS: 00000246 ORIG_RAX: 00000000000000b0
[  137.523062] RAX: ffffffffffffffda RBX: ffffffff81493f33 RCX: 00007f7bd0609287
[  137.523065] RDX: 0000000000000001 RSI: 0000000000000800 RDI: 0000564f999f9fc8
[  137.523067] RBP: ffffc90005c4ff88 R08: 0000000000000000 R09: 0000000000000080
[  137.523069] R10: 00007f7bd20ef8c0 R11: 0000000000000246 R12: 0000000000000000
[  137.523072] R13: 00007ffef694be00 R14: 0000000000000000 R15: 0000000000000000
[  137.523075]  ? __this_cpu_preempt_check+0x13/0x20
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20171011141857.14161-1-chris@chris-wilson.co.ukReviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Get rid of redundant intel_dp_num_rates(). We can simply look at the
rate and limit based on that.

Cc: Manasi Navare <manasi.d.navare@intel.com>
Reviewed-by: <manasi.d.navare@intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171009092959.29021-3-jani.nikula@intel.com

Turn intel_dp_source_supports_hbr2() into a simple helper to query the
pre-filled source rates array, and move the conditions about which
platforms support which rates to the single point of truth in
intel_dp_set_source_rates().

This also reduces the code paths you have to think about in the source
rates initialization in intel_dp_set_source_rates(), making it easier to
grasp.

Cc: Manasi Navare <manasi.d.navare@intel.com>
Reviewed-by: NManasi Navare <manasi.d.navare@intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171009092959.29021-2-jani.nikula@intel.com

With intel_encoder_current_mode() using the normal state readout code it
actually works on PCH platforms as well. So let's nuke the PCH check from
intel_lvds_init(). I suppose there aren't any machines that actually
need this, but at least we get to eliminate a few lines of code, and one
FIXME.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171009161951.22420-2-ville.syrjala@linux.intel.comReviewed-by: NChris Wilson <chris@chris-wilson.co.uk>

Reuse the normal state readout code to get the fixed mode for LVDS/DVO
encoders. This removes some partially duplicated state readout code
from LVDS/DVO encoders. The duplicated code wasn't actually even
populating the negative h/vsync flags, leading to possible state checker
complaints. The normal readout code populates that stuff fully.

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171009161951.22420-1-ville.syrjala@linux.intel.comReviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Tested-by: NChris Wilson <chris@chris-wilson.co.uk>

stop_machine is not really a locking primitive we should use, except
when the hw folks tell us the hw is broken and that's the only way to
work around it.

This patch tries to address the locking abuse of stop_machine() from

commit 20e4933c
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Tue Nov 22 14:41:21 2016 +0000

    drm/i915: Stop the machine as we install the wedged submit_request handler

Chris said parts of the reasons for going with stop_machine() was that
it's no overhead for the fast-path. But these callbacks use irqsave
spinlocks and do a bunch of MMIO, and rcu_read_lock is _real_ fast.

To stay as close as possible to the stop_machine semantics we first
update all the submit function pointers to the nop handler, then call
synchronize_rcu() to make sure no new requests can be submitted. This
should give us exactly the huge barrier we want.

I pondered whether we should annotate engine->submit_request as __rcu
and use rcu_assign_pointer and rcu_dereference on it. But the reason
behind those is to make sure the compiler/cpu barriers are there for
when you have an actual data structure you point at, to make sure all
the writes are seen correctly on the read side. But we just have a
function pointer, and .text isn't changed, so no need for these
barriers and hence no need for annotations.

Unfortunately there's a complication with the call to
intel_engine_init_global_seqno:

- Without stop_machine we must hold the corresponding spinlock.

- Without stop_machine we must ensure that all requests are marked as
  having failed with dma_fence_set_error() before we call it. That
  means we need to split the nop request submission into two phases,
  both synchronized with rcu:

  1. Only stop submitting the requests to hw and mark them as failed.

  2. After all pending requests in the scheduler/ring are suitably
  marked up as failed and we can force complete them all, also force
  complete by calling intel_engine_init_global_seqno().

This should fix the followwing lockdep splat:

======================================================
WARNING: possible circular locking dependency detected
4.14.0-rc3-CI-CI_DRM_3179+ #1 Tainted: G     U
------------------------------------------------------
kworker/3:4/562 is trying to acquire lock:
 (cpu_hotplug_lock.rw_sem){++++}, at: [<ffffffff8113d4bc>] stop_machine+0x1c/0x40

but task is already holding lock:
 (&dev->struct_mutex){+.+.}, at: [<ffffffffa0136588>] i915_reset_device+0x1e8/0x260 [i915]

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #6 (&dev->struct_mutex){+.+.}:
       __lock_acquire+0x1420/0x15e0
       lock_acquire+0xb0/0x200
       __mutex_lock+0x86/0x9b0
       mutex_lock_interruptible_nested+0x1b/0x20
       i915_mutex_lock_interruptible+0x51/0x130 [i915]
       i915_gem_fault+0x209/0x650 [i915]
       __do_fault+0x1e/0x80
       __handle_mm_fault+0xa08/0xed0
       handle_mm_fault+0x156/0x300
       __do_page_fault+0x2c5/0x570
       do_page_fault+0x28/0x250
       page_fault+0x22/0x30

-> #5 (&mm->mmap_sem){++++}:
       __lock_acquire+0x1420/0x15e0
       lock_acquire+0xb0/0x200
       __might_fault+0x68/0x90
       _copy_to_user+0x23/0x70
       filldir+0xa5/0x120
       dcache_readdir+0xf9/0x170
       iterate_dir+0x69/0x1a0
       SyS_getdents+0xa5/0x140
       entry_SYSCALL_64_fastpath+0x1c/0xb1

-> #4 (&sb->s_type->i_mutex_key#5){++++}:
       down_write+0x3b/0x70
       handle_create+0xcb/0x1e0
       devtmpfsd+0x139/0x180
       kthread+0x152/0x190
       ret_from_fork+0x27/0x40

-> #3 ((complete)&req.done){+.+.}:
       __lock_acquire+0x1420/0x15e0
       lock_acquire+0xb0/0x200
       wait_for_common+0x58/0x210
       wait_for_completion+0x1d/0x20
       devtmpfs_create_node+0x13d/0x160
       device_add+0x5eb/0x620
       device_create_groups_vargs+0xe0/0xf0
       device_create+0x3a/0x40
       msr_device_create+0x2b/0x40
       cpuhp_invoke_callback+0xc9/0xbf0
       cpuhp_thread_fun+0x17b/0x240
       smpboot_thread_fn+0x18a/0x280
       kthread+0x152/0x190
       ret_from_fork+0x27/0x40

-> #2 (cpuhp_state-up){+.+.}:
       __lock_acquire+0x1420/0x15e0
       lock_acquire+0xb0/0x200
       cpuhp_issue_call+0x133/0x1c0
       __cpuhp_setup_state_cpuslocked+0x139/0x2a0
       __cpuhp_setup_state+0x46/0x60
       page_writeback_init+0x43/0x67
       pagecache_init+0x3d/0x42
       start_kernel+0x3a8/0x3fc
       x86_64_start_reservations+0x2a/0x2c
       x86_64_start_kernel+0x6d/0x70
       verify_cpu+0x0/0xfb

-> #1 (cpuhp_state_mutex){+.+.}:
       __lock_acquire+0x1420/0x15e0
       lock_acquire+0xb0/0x200
       __mutex_lock+0x86/0x9b0
       mutex_lock_nested+0x1b/0x20
       __cpuhp_setup_state_cpuslocked+0x53/0x2a0
       __cpuhp_setup_state+0x46/0x60
       page_alloc_init+0x28/0x30
       start_kernel+0x145/0x3fc
       x86_64_start_reservations+0x2a/0x2c
       x86_64_start_kernel+0x6d/0x70
       verify_cpu+0x0/0xfb

-> #0 (cpu_hotplug_lock.rw_sem){++++}:
       check_prev_add+0x430/0x840
       __lock_acquire+0x1420/0x15e0
       lock_acquire+0xb0/0x200
       cpus_read_lock+0x3d/0xb0
       stop_machine+0x1c/0x40
       i915_gem_set_wedged+0x1a/0x20 [i915]
       i915_reset+0xb9/0x230 [i915]
       i915_reset_device+0x1f6/0x260 [i915]
       i915_handle_error+0x2d8/0x430 [i915]
       hangcheck_declare_hang+0xd3/0xf0 [i915]
       i915_hangcheck_elapsed+0x262/0x2d0 [i915]
       process_one_work+0x233/0x660
       worker_thread+0x4e/0x3b0
       kthread+0x152/0x190
       ret_from_fork+0x27/0x40

other info that might help us debug this:

Chain exists of:
  cpu_hotplug_lock.rw_sem --> &mm->mmap_sem --> &dev->struct_mutex

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&dev->struct_mutex);
                               lock(&mm->mmap_sem);
                               lock(&dev->struct_mutex);
  lock(cpu_hotplug_lock.rw_sem);

 *** DEADLOCK ***

3 locks held by kworker/3:4/562:
 #0:  ("events_long"){+.+.}, at: [<ffffffff8109c64a>] process_one_work+0x1aa/0x660
 #1:  ((&(&i915->gpu_error.hangcheck_work)->work)){+.+.}, at: [<ffffffff8109c64a>] process_one_work+0x1aa/0x660
 #2:  (&dev->struct_mutex){+.+.}, at: [<ffffffffa0136588>] i915_reset_device+0x1e8/0x260 [i915]

stack backtrace:
CPU: 3 PID: 562 Comm: kworker/3:4 Tainted: G     U          4.14.0-rc3-CI-CI_DRM_3179+ #1
Hardware name:                  /NUC7i5BNB, BIOS BNKBL357.86A.0048.2017.0704.1415 07/04/2017
Workqueue: events_long i915_hangcheck_elapsed [i915]
Call Trace:
 dump_stack+0x68/0x9f
 print_circular_bug+0x235/0x3c0
 ? lockdep_init_map_crosslock+0x20/0x20
 check_prev_add+0x430/0x840
 ? irq_work_queue+0x86/0xe0
 ? wake_up_klogd+0x53/0x70
 __lock_acquire+0x1420/0x15e0
 ? __lock_acquire+0x1420/0x15e0
 ? lockdep_init_map_crosslock+0x20/0x20
 lock_acquire+0xb0/0x200
 ? stop_machine+0x1c/0x40
 ? i915_gem_object_truncate+0x50/0x50 [i915]
 cpus_read_lock+0x3d/0xb0
 ? stop_machine+0x1c/0x40
 stop_machine+0x1c/0x40
 i915_gem_set_wedged+0x1a/0x20 [i915]
 i915_reset+0xb9/0x230 [i915]
 i915_reset_device+0x1f6/0x260 [i915]
 ? gen8_gt_irq_ack+0x170/0x170 [i915]
 ? work_on_cpu_safe+0x60/0x60
 i915_handle_error+0x2d8/0x430 [i915]
 ? vsnprintf+0xd1/0x4b0
 ? scnprintf+0x3a/0x70
 hangcheck_declare_hang+0xd3/0xf0 [i915]
 ? intel_runtime_pm_put+0x56/0xa0 [i915]
 i915_hangcheck_elapsed+0x262/0x2d0 [i915]
 process_one_work+0x233/0x660
 worker_thread+0x4e/0x3b0
 kthread+0x152/0x190
 ? process_one_work+0x660/0x660
 ? kthread_create_on_node+0x40/0x40
 ret_from_fork+0x27/0x40
Setting dangerous option reset - tainting kernel
i915 0000:00:02.0: Resetting chip after gpu hang
Setting dangerous option reset - tainting kernel
i915 0000:00:02.0: Resetting chip after gpu hang

v2: Have 1 global synchronize_rcu() barrier across all engines, and
improve commit message.

v3: We need to protect the seqno update with the timeline spinlock (in
set_wedged) to avoid racing with other updates of the seqno, like we
already do in nop_submit_request (Chris).

v4: Use two-phase sequence to plug the race Chris spotted where we can
complete requests before they're marked up with -EIO.

v5: Review from Chris:
- simplify nop_submit_request.
- Add comment to rcu_read_lock section.
- Align comments with the new style.

v6: Remove unused variable to appease CI.
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=102886
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=103096
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Marta Lofstedt <marta.lofstedt@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171011091019.1425-1-daniel.vetter@ffwll.ch

Defined new struct intel_rc6 to hold RC6 specific state and
intel_ring_pstate to hold ring specific state.

v2: s/intel_ring_pstate/intel_llc_pstate. Removed checks from
autoenable_* functions. (Chris)
Signed-off-by: NSagar Arun Kamble <sagar.a.kamble@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Radoslaw Szwichtenberg <radoslaw.szwichtenberg@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/1507360055-19948-13-git-send-email-sagar.a.kamble@intel.comAcked-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171010213010.7415-12-chris@chris-wilson.co.uk

Prepared generic functions intel_enable_rc6, intel_disable_rc6,
intel_enable_rps and intel_disable_rps functions to setup RC6/RPS
based on platforms.

v2: Make intel_enable/disable_rc6/rps static. (Chris)

v3: Added lockdep_assert_held(dev_priv->pcu_lock) in new generic
functions. (Chris)
Removed WARN_ON(&dev_priv->pcu_lock) from lower level functions as generic
function now has lockdep_assert. Rebase.
Signed-off-by: NSagar Arun Kamble <sagar.a.kamble@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Radoslaw Szwichtenberg <radoslaw.szwichtenberg@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/1507360055-19948-12-git-send-email-sagar.a.kamble@intel.comAcked-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171010213010.7415-11-chris@chris-wilson.co.uk

Prepared intel_update_ring_freq function to setup ring frequency
for applicable platforms determined by macro HAS_LLC.

v2: Replaced NEEDS_RING_FREQ_UPDATE with HAS_LLC macro. (Chris)
    Added check while calling from intel_enable_gt_powersave.

v3: s/intel_update_ring_freq/intel_enable_llc_pstate and created
new placeholder function intel_disable_llc_pstate. (Chris)
Signed-off-by: NSagar Arun Kamble <sagar.a.kamble@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Radoslaw Szwichtenberg <radoslaw.szwichtenberg@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/1507360055-19948-11-git-send-email-sagar.a.kamble@intel.comAcked-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171010213010.7415-10-chris@chris-wilson.co.uk

This function gives the status of RC6, whether disabled or if
enabled then which state. intel_enable_rc6 will be used for
enabling RC6 in the next patch.

v2: Rebase.

v3: Rebase.
Signed-off-by: NSagar Arun Kamble <sagar.a.kamble@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Radoslaw Szwichtenberg <radoslaw.szwichtenberg@intel.com> #1
Reviewed-by: Ewelina Musial <ewelina.musial@intel.com> #1Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/1507360055-19948-10-git-send-email-sagar.a.kamble@intel.comAcked-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171010213010.7415-9-chris@chris-wilson.co.uk

Prepared substructure rps for RPS related state. autoenable_work is
used for RC6 too hence it is defined outside rps structure. As we do
this lot many functions are refactored to use intel_rps *rps to access
rps related members. Hence renamed intel_rps_client pointer variables
to rps_client in various functions.

v2: Rebase.

v3: s/pm/gt_pm (Chris)
Refactored access to rps structure by declaring struct intel_rps * in
many functions.
Signed-off-by: NSagar Arun Kamble <sagar.a.kamble@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Radoslaw Szwichtenberg <radoslaw.szwichtenberg@intel.com> #1
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/1507360055-19948-9-git-send-email-sagar.a.kamble@intel.comAcked-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171010213010.7415-8-chris@chris-wilson.co.uk