With that the drm_pci_device_is_agp function becomes trivial, so
inline that too. And while at it, move the drm_pci_agp_destroy
declaration into drm-internal.h, since it's not used by drivers.

Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170125062657.19270-11-daniel.vetter@ffwll.ch

After going through all the trouble of splitting out parts from
drm_crtc.[hc] and then properly documenting each I've entirely
forgotten to show the same TLC for CRTCs themselves!

Let's make amends asap.

v2: Review from Eric.
Reviewed-by: NEric Engestrom <eric.engestrom@imgtec.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>

I just learned that &struct_name.member_name works and looks pretty
even. It doesn't (yet) link to the member directly though, which would
be really good for big structures or vfunc tables (where the
per-member kerneldoc tends to be long).

Also some minor drive-by polish where it makes sense, I read a lot
of docs ...

v2: Review from Eric.

Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NEric Engestrom <eric.engestrom@imgtec.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170125062657.19270-4-daniel.vetter@ffwll.ch

I just learned that &struct_name.member_name works and looks pretty
even. It doesn't (yet) link to the member directly though, which would
be really good for big structures or vfunc tables (where the
per-member kerneldoc tends to be long).

Also some minor drive-by polish where it makes sense, I read a lot
of docs ...

v2: Review from Gustavo.

Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NGustavo Padovan <gustavo.padovan@collabora.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170125062657.19270-6-daniel.vetter@ffwll.ch

I just learned that &struct_name.member_name works and looks pretty
even. It doesn't (yet) link to the member directly though, which would
be really good for big structures or vfunc tables (where the
per-member kerneldoc tends to be long).

Also some minor drive-by polish where it makes sense, I read a lot
of docs ...

Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NGustavo Padovan <gustavo.padovan@collabora.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170125062657.19270-5-daniel.vetter@ffwll.ch

I just learned that &struct_name.member_name works and looks pretty
even. It doesn't (yet) link to the member directly though, which would
be really good for big structures or vfunc tables (where the
per-member kerneldoc tends to be long).

Also some minor drive-by polish where it makes sense, I read a lot
of docs ...

v2: Comments from Gustavo.

Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Rewiewed-by: NGustavo Padovan <gustavo.padovan@collabora.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170125062657.19270-2-daniel.vetter@ffwll.ch

struct drm_dp_mst_topology_mgr currently stores a pointer to struct dev.
Changing this to instead hold a pointer to drm_device is more useful as it
gives access to DRM structures. This also makes it consistent with other
DRM structures like drm_crtc, drm_connector etc.
Signed-off-by: NDhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Reviewed-by: NDave Airlie <airlied@redhat.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1485301777-3465-2-git-send-email-dhinakaran.pandiyan@intel.com

Add missing includes to pull in definitions for drm_crtc,
drm_plane and drm_encoder.
Signed-off-by: NNoralf Trønnes <noralf@tronnes.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170122181117.8210-4-noralf@tronnes.org

Add a CMA version of drm_fb_helper_set_suspend_unlocked().

Cc: laurent.pinchart@ideasonboard.com
Signed-off-by: NNoralf Trønnes <noralf@tronnes.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170122181117.8210-2-noralf@tronnes.org

Detect the PHY type and use it to handle the PHY type-specific SVSRET
signal.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: NArchit Taneja <architt@codeaurora.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20170117082910.27023-17-laurent.pinchart+renesas@ideasonboard.com

As an option for drivers not based on the component framework, register
the bridge with the DRM core with the DRM bridge API. Existing drivers
based on dw_hdmi_bind() and dw_hdmi_unbind() are not affected as those
functions are preserved with their current behaviour.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: NJose Abreu <joabreu@synopsys.com>
Signed-off-by: NArchit Taneja <architt@codeaurora.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20170117082910.27023-11-laurent.pinchart+renesas@ideasonboard.com

There's no need to duplicate identical code in multiple drivers (two at
the moment, one more to come soon). Move it to the dw-hdmi core where it
can be shared. If resource allocation ever becomes device-specific later
we'll always have the option of splitting it out again.

While it at pass the platform device to the bind function to avoid
having to cast struct device to struct platform_device.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: NJose Abreu <joabreu@synopsys.com>
Signed-off-by: NArchit Taneja <architt@codeaurora.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20170117082910.27023-8-laurent.pinchart+renesas@ideasonboard.com

The master argument isn't used. The data argument, a void pointer, is
used by the bind function only where it's cast to a drm_device pointer,
which can easily be obtained from the encoder argument instead. Remove
them.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: NJose Abreu <joabreu@synopsys.com>
Signed-off-by: NArchit Taneja <architt@codeaurora.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20170117082910.27023-3-laurent.pinchart+renesas@ideasonboard.com

Allows usage of the new page_flip_target hook for drivers implementing
the atomic path.
Provides default atomic helper for the new hook.

v2:
Update code sharing logic between exsiting and the new flip hooks.
Improve kerneldoc.
Signed-off-by: NAndrey Grodzovsky <Andrey.Grodzovsky@amd.com>
Acked-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1483735180-4173-1-git-send-email-Andrey.Grodzovsky@amd.com

Continue to clean up drmP.h by moving the cache flushing functions into
it's own header file.

Compile-tested only
Signed-off-by: NGabriel Krisman Bertazi <krisman@collabora.co.uk>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170109215649.6860-2-krisman@collabora.co.uk

The integer returned by the unload hook is ignored by the drm core, so
let's make it void.

This patch was created using the following Coccinelle semantic script
(except for the declaration and comment in drm_drv.h):

Compile-tested only.

// <smpl>
@ get_name @
struct drm_driver drv;
identifier fn;
@@
drv.unload = fn;

@ replace_type @
identifier get_name.fn;
@@
- int
+ void
fn (...)
{
...
}

@ remove_return_param @
identifier get_name.fn;
@@
void fn (...)
{
<...
if (...)
return
- ...
;
...>
 }

@ drop_final_return @
identifier get_name.fn;
@@
void fn (...)
{
...

- return 0;
}
// </smpl>
Suggested-by: NDaniel Vetter <daniel.vetter@intel.com>
Signed-off-by: NGabriel Krisman Bertazi <krisman@collabora.co.uk>
Acked-by: Christian König <christian.koenig@amd.com>.
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170106175731.29196-1-krisman@collabora.co.uk

drm_pick_cmdline_mode width and height parameters are useless.
Just remove them.

Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: NVincent Abriou <vincent.abriou@st.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1483721084-20278-2-git-send-email-vincent.abriou@st.com

Stolen memory is a hardware resource of known size, so use an accurate
fixed integer type rather than the ambiguous variable size_t. This was
motivated by the next patch spotting inconsistencies in our types.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170106152013.24684-3-chris@chris-wilson.co.uk

Some SoC without MMU have display driver where a drm/kms driver
could be implemented.

Before doing such kind of thing drm/kms must allow to use mmuless devices.
This patch propose to remove MMU configuration flag and add a cma helper
function to help implementing mmuless display driver

version 4:
- add documentation about drm_gem_cma_get_unmapped_area()
- stub it MMU case
Signed-off-by: NBenjamin Gaignard <benjamin.gaignard@linaro.org>
[danvet: Use recommended struct member references in kernel-doc.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1483521177-21794-4-git-send-email-benjamin.gaignard@linaro.org

I was lazy, rectify that! Also align with drm_atomic_state_get/put for
ocd.

v2: Git add helps.
Acked-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161221130335.5321-1-daniel.vetter@ffwll.ch

Commit 8d9c20e1 ("drm/i915: Remove .is_mobile field from platform
struct") removed mobile vs desktop differences for HSW+, but forgot
the Broadwell reserved IDs, so do it now.

It's interesting to notice that these IDs are used by early-quirks.c
but are *not* used by i915_pci.c.

Cc: Carlos Santa <carlos.santa@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1483473860-17644-2-git-send-email-paulo.r.zanoni@intel.com

Remove duplicated IDs from the list. Currently, this definition is
only used by early-quirks.c. From my understanding of the code, having
duplicated IDs shouldn't be causing any bugs.

Fixes: 8d9c20e1 ("drm/i915: Remove .is_mobile field from platform struct")
Cc: Carlos Santa <carlos.santa@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1483473860-17644-1-git-send-email-paulo.r.zanoni@intel.com

When writing the generic nonblocking commit code I assumed that
through clever lifetime management I can assure that the completion
(stored in drm_crtc_commit) only gets freed after it is completed. And
that worked.

I also wanted to make nonblocking helpers resilient against driver
bugs, by having timeouts everywhere. And that worked too.

Unfortunately taking boths things together results in oopses :( Well,
at least sometimes: What seems to happen is that the drm event hangs
around forever stuck in limbo land. The nonblocking helpers eventually
time out, move on and release it. Now the bug I tested all this
against is drivers that just entirely fail to deliver the vblank
events like they should, and in those cases the event is simply
leaked. But what seems to happen, at least sometimes, on i915 is that
the event is set up correctly, but somohow the vblank fails to fire in
time. Which means the event isn't leaked, it's still there waiting for
eventually a vblank to fire. That tends to happen when re-enabling the
pipe, and then the trap springs and the kernel oopses.

The correct fix here is simply to refcount the crtc commit to make
sure that the event sticks around even for drivers which only
sometimes fail to deliver vblanks for some arbitrary reasons. Since
crtc commits are already refcounted that's easy to do.

References: https://bugs.freedesktop.org/show_bug.cgi?id=96781
Cc: Jim Rees <rees@umich.edu>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161221102331.31033-1-daniel.vetter@ffwll.ch

v2:
 - Replace discouraged with deprecated
 - Link to new initialization/teardown functions
Signed-off-by: NGabriel Krisman Bertazi <krisman@collabora.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170102142008.22174-3-krisman@collabora.co.uk

No functional changes. Apparently spec has been changed
the valid table showing 0x192A as Server GT4
while 0x193A is Server GT4e.

Libdrm and Mesa already have this right. So let's fix the ref here.

Cc: Ben Widawsky <benjamin.widawsky@intel.com>
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NBen Widawsky <benjamin.widawsky@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1483471672-10450-1-git-send-email-rodrigo.vivi@intel.com

I just learned that &struct_name.member_name works and looks pretty
even. It doesn't (yet) link to the member directly though, which would
be really good for big structures or vfunc tables (where the
per-member kerneldoc tends to be long).

Also some minor drive-by polish where it makes sense, I read a lot
of docs ...

Cc: Archit Taneja <architt@codeaurora.org>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NArchit Taneja <architt@codeaurora.org>
[danvet: Remove spurious hunk that Archit spotted.]
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1483044517-5770-13-git-send-email-daniel.vetter@ffwll.ch

If we store the fb funcs pointer, we can remove a bit of boilerplate.
Also remove the _fbdev_ in the example code, since the fb_funcs->dirty
callback has nothing to do with fbdev. It's a KMS feature, only
used by the fbdev deferred_io support to implement flushing/upload.

Cc: Noralf Trønnes <noralf@tronnes.org>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
[danvet: Move the misplaced kerneldoc change from a later patch to
this one here.]
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1483044517-5770-11-git-send-email-daniel.vetter@ffwll.ch

I've forgotten to remove this when revamping the
connector_list locking.

Cc: seanpaul@chromium.org
Reviewed-by: NDavid Herrmann <dh.herrmann@gmail.com>
Reviewed-by: NSean Paul <seanpaul@chromium.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1483044517-5770-7-git-send-email-daniel.vetter@ffwll.ch

sed -e 's/\( \* .*\)struct &\([_a-z]*\)/\1\&struct \2/' -i

Originally I wasnt a friend of this style because I thought a
line-break between the "&struct" and "foo" part would break it. But a
quick test shows that " * &struct \n * foo\n" works pefectly well with
current kernel-doc. So time to mass-apply these changes!

Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1483044517-5770-6-git-send-email-daniel.vetter@ffwll.ch

Added some boilerplate for the structs, documented members where they
are relevant and plenty of markup for hyperlinks all over. And a few
small wording polish.

Note that the intro needs some more love after the DRM_MM_INSERT_*
patch from Chris has landed.

v2: Spelling fixes (Chris).

v3: Use &struct foo instead of &foo structure (Chris).

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1483044517-5770-3-git-send-email-daniel.vetter@ffwll.ch

It adds a crtc helper drm_crtc_from_index() to find the registered CRTC
with a given index, just like drm_plane_from_index().
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1483015290-16660-2-git-send-email-shawnguo@kernel.org

Including all drivers. I thought about keeping small compat functions
to avoid having to change all drivers. But I really like the
drm_printer idea, so figured spreading it more widely is a good thing.

v2: Review from Chris:
- Natural argument order and better name for drm_mm_print.
- show_mm() macro in the selftest.

Cc: Rob Clark <robdclark@gmail.com>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jyri Sarha <jsarha@ti.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1483009764-8281-1-git-send-email-daniel.vetter@ffwll.ch

Useful for dumping lots of data into dmesg, e.g. drm_mm.

v2: Fixup export_symbol line, I misplaced a hunk (Chris).

Cc: Rob Clark <robdclark@gmail.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1482943330-11592-1-git-send-email-daniel.vetter@ffwll.ch

Remove a superfluous helper as drm_mm_insert_node is equivalent to
insert_node_in_range with a range of [0, U64_MAX].
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161222083641.2691-37-chris@chris-wilson.co.uk

Insulate users from changes to the internal hole tracking within
struct drm_mm_node by using an accessor for hole_follows.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
[danvet: resolve conflicts in i915_vma.c]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Using mm->color_adjust makes the eviction scanner much tricker since we
don't know the actual neighbours of the target hole until after it is
created (after scanning is complete). To work out whether we need to
evict the neighbours because they impact upon the hole, we have to then
check the hole afterwards - requiring an extra step in the user of the
eviction scanner when they apply color_adjust.

v2: Massage kerneldoc.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161222083641.2691-34-chris@chris-wilson.co.uk

Since we mandate a strict reverse-order of drm_mm_scan_remove_block()
after drm_mm_scan_add_block() we can further simplify the list
manipulations when generating the temporary scan-hole.

v2: Highlight the games being played with the lists to track the scan
holes without allocation.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161222083641.2691-33-chris@chris-wilson.co.uk

For power-of-two alignments, we can avoid the 64bit divide and do a
simple bitwise add instead.

v2: s/alignment_mask/remainder_mask/
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161222083641.2691-32-chris@chris-wilson.co.uk

Compute the minimal required hole during scan and only evict those nodes
that overlap. This enables us to reduce the number of nodes we need to
evict to the bare minimum.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161222083641.2691-31-chris@chris-wilson.co.uk

Doing the check is trivial (low cost in comparison to overall eviction)
and helps simplify the code.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161222083641.2691-29-chris@chris-wilson.co.uk