This is to workaround guest driver hang regression after
preemption enable that gvt hasn't enabled handling of that
for guest workload. So in effect this disables preemption
for gvt context now.
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
(cherry picked from commit 1603660b33)
We shouldn't mark inactive for vGPU context if preempted,
which would still be re-scheduled later. So keep active state.
Fixes: d6c0511300 ("drm/i915/execlists: Distinguish the incomplete context notifies")
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
(cherry picked from commit da5f99eacc)
mmio_read_from_hw() let vgpu could read hw reg, if vgpu's workload
is running on hw, things is good. Otherwise vgpu will get other
vgpu's reg val, it is unsafe.
This patch limit such hw access to active vgpu. If vgpu isn't
running on hw, the reg read of this vgpu will get the last active
val which saved at schedule_out.
v2: ring timestamp is walking continuously even if the ring is idle.
so read hw directly. (Zhenyu)
Signed-off-by: Xiong Zhang <xiong.y.zhang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
(cherry picked from commit 295764cd2f)
Since many emulation logic needs to convert the offset of ring registers
into ring id, we export it for other caller which might need it.
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
(cherry picked from commit 62a6a53786)
Our vGPU doesn't have a device ROM, we need follow the PCI spec to
report this info to drivers. Otherwise, we would see below errors.
Inspecting possible rom at 0xfe049000 (vd=8086:1912 bdf=00:10.0)
qemu-system-x86_64: vfio-pci: Cannot read device rom at 00000000-0000-0000-0000-000000000001
Device option ROM contents are probably invalid (check dmesg).
Skip option ROM probe with rombar=0, or load from file with romfile=No option rom signature (got 4860)
I will also send a improvement patch to PCI subsystem related to PCI ROM.
But no idea to omit below error, since no pattern to detect vbios shadow
without touch its content.
0000:00:10.0: Invalid PCI ROM header signature: expecting 0xaa55, got 0x0000
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
(cherry picked from commit c4270d122c)
History tells us that if we cannot reset the GPU now, we never will. This
then impacts everything that is run subsequently. On failing the reset,
we mark the driver as wedged, trying to prevent further execution on the
GPU, forcing userspace to fallback to using the CPU to update its
framebuffers and let the user know what happened.
We also want to go one step further and add a taint to the kernel so that
any subsequent faults can be traced back to this failure. This is
useful for CI, where if the GPU/driver fails we want to reboot and
restart testing rather than continue on into oblivion. For everyone
else, the warning taint is a testament to the system unreliability.
TAINT_WARN is used anytime a WARN() is emitted, which is suitable for
our purposes here as well; the driver/system may behave unexpectedly
after the failure.
v2: Also taint if the recovery fails (again history shows us that is
typically fatal).
v3: Use TAINT_WARN
References: https://bugs.freedesktop.org/show_bug.cgi?id=103514
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Michał Winiarski <michal.winiarski@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Acked-by: Tomi Sarvela <tomi.p.sarvela@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171205172757.32609-1-chris@chris-wilson.co.uk
From the shrinker paths, we want to relinquish the GPU and GGTT access to
the object, releasing the backing storage back to the system for
swapout. As a part of that process we would unpin the pages, marking
them for access by the CPU (for the swapout/swapin). However, if that
process was interrupted after unbind the vma, we missed a flush of the
inflight GGTT writes before we made that GTT space available again for
reuse, with the prospect that we would redirect them to another page.
The bug dates back to the introduction of multiple GGTT vma, but the
code itself dates to commit 02bef8f98d ("drm/i915: Unbind closed vma
for i915_gem_object_unbind()").
Fixes: 02bef8f98d ("drm/i915: Unbind closed vma for i915_gem_object_unbind()")
Fixes: c5ad54cf7d ("drm/i915: Use partial view in mmap fault handler")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: stable@vger.kernel.org
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171204132513.7303-1-chris@chris-wilson.co.uk
Previously I was under the impression that the scanline counter
reads 0 when the pipe is off. Turns out that's not correct, and
instead the scanline counter simply stops when the pipe stops, and
it retains it's last value until the pipe starts up again, at which
point the scanline counter jumps to vblank start.
These jumps can cause the timestamp to jump backwards by one frame.
Since we use the timestamps to guesstimage also the frame counter
value on gen2, that would cause the frame counter to also jump
backwards, which leads to a massice difference from the previous value.
The end result is that flips/vblank events don't appear to complete as
they're stuck waiting for the frame counter to catch up to that massive
difference.
Fix the problem properly by actually making sure the scanline counter
has started to move before we assume that it's safe to enable vblank
processing.
v2: Less pointless duplication in the code (Chris)
Cc: stable@vger.kernel.org
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Fixes: b7792d8b54 ("drm/i915: Wait for pipe to start before sampling vblank timestamps on gen2")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171129153732.3612-1-ville.syrjala@linux.intel.com
(cherry picked from commit 8fedd64dab)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
The ring_id maximum boundary is being compared using the > operator
instead of >=, leading to an off-by-one error and an out of bounds
write into array vgpu->hws_pga[]. Fix this by simply using the
correct comparison operator. Also re-work another comparison that
uses the comparison > I915_NUM_ENGINES - 1 to use the >= idiom using
to keep this consistent in this code.
Detected by CoverityScan, CID#1462404 ("Out-of-bounds write")
Fixes: a2ae95af96 ("drm/i915/gvt: update CSB and CSB write pointer in virtual HWSP")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
The switch statement is missing breaks for the cases of
GVT_FAILSAFE_INSUFFICIENT_RESOURCE and GVT_FAILSAFE_GUEST_ERR. Add them
in.
Detected by CoverityScan, CID#1462416 ("Missing break in switch")
Fixes: e011c6ce2b ("drm/i915/gvt: Add VM healthy check for workload_thread")
Fixes: a33fc7a048 ("drm/i915/gvt: enter failsafe mode when guest requires more resources")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Ideally we could use the VBT for this, that would be simple, in
intel_dsi_init() check dev_priv->vbt.dsi.config->rotation, set
connector->display_info.panel_orientation accordingly and call
drm_connector_init_panel_orientation_property(), done.
Unfortunately vbt.dsi.config->rotation is always 0 even on tablets
with an upside down LCD and where the GOP is properly rotating the
EFI fb in hardware.
So instead we end up reading the rotation from the primary plane.
This commit only implements the panel orientation property for DSI
panels on BYT / CHT hardware, as all known non normal oriented panels
sofar are only found on this hardware.
Changes in v2:
-Read back the rotation applied by the GOP from the primary plane
instead of relying on dev_priv->vbt.dsi.config->rotation, because it
seems that the VBT rotation filed is always 0 even on devices where the
GOP does apply a rotation
Changes in v3:
-Rewrite the code to read back the orientation from the primary
plane to contain all of this in intel_dsi.c instead of poking a bunch
of holes between all the different layers
Changes in v6:
-Move hardware readout to intel_dsi_init()
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171125193553.23986-6-hdegoede@redhat.com
This is to workaround guest driver hang regression after
preemption enable that gvt hasn't enabled handling of that
for guest workload. So in effect this disables preemption
for gvt context now.
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
We shouldn't mark inactive for vGPU context if preempted,
which would still be re-scheduled later. So keep active state.
Fixes: d6c0511300 ("drm/i915/execlists: Distinguish the incomplete context notifies")
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
The current schedule policy rely on a 1ms timer to execute workload. This
can introduce maximum 1ms unnecessary latency. This is especially bad for
small media workloads.
And I don't think we need this timer for QoS, but the change is not simply
remove the code. So I made a new API intel_gvt_kick_schedule() for future
change.
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
The per vGPU dmabuf_obj list should be released in intel_vgpu_dmabuf_
cleanup, which is invoked either in the process of closing a VM or in
the process of removing a vGPU.
Fixes: e3a0d7976c53 ("drm/i915/gvt: Handle orphan dmabuf_objs")
Signed-off-by: Tina Zhang <tina.zhang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
dmabuf_obj's destruction relys on GEM release operation, which is managed
in i915 driver. And there is a time window between vgpu's destruction and
its dmabuf_objs' destruction. This patch is to free the orphan dmabuf_objs
correctly after the vgpu passes away.
Signed-off-by: Tina Zhang <tina.zhang@intel.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introduces a guest's framebuffer sharing mechanism based on
dma-buf subsystem. With this sharing mechanism, guest's framebuffer can
be shared between guest VM and host.
v17:
- modify VFIO_DEVICE_GET_GFX_DMABUF interface. (Alex)
v16:
- add x_hot and y_hot. (Gerd)
- add flag validation for VFIO_DEVICE_GET_GFX_DMABUF. (Alex)
- rebase 4.14.0-rc6.
v15:
- add VFIO_DEVICE_GET_GFX_DMABUF ABI. (Gerd)
- add intel_vgpu_dmabuf_cleanup() to clean up the vGPU's dmabuf. (Gerd)
v14:
- add PROBE, DMABUF and REGION flags. (Alex)
v12:
- refine the lifecycle of dmabuf.
v9:
- remove dma-buf management. (Alex)
- track the dma-buf create and release in kernel mode. (Gerd) (Daniel)
v8:
- refine the dma-buf ioctl definition.(Alex)
- add a lock to protect the dmabuf list. (Alex)
v7:
- release dma-buf related allocations in dma-buf's associated release
function. (Alex)
- refine ioctl interface for querying plane info or create dma-buf.
(Alex)
v6:
- align the dma-buf life cycle with the vfio device. (Alex)
- add the dma-buf related operations in a separate patch. (Gerd)
- i915 related changes. (Chris)
v5:
- fix bug while checking whether the gem obj is gvt's dma-buf when user
change caching mode or domains. Add a helper function to do it.
(Xiaoguang)
- add definition for the query plane and create dma-buf. (Xiaoguang)
v4:
- fix bug while checking whether the gem obj is gvt's dma-buf when set
caching mode or doamins. (Xiaoguang)
v3:
- declare a new flag I915_GEM_OBJECT_IS_GVT_DMABUF in drm_i915_gem_object
to represent the gem obj for gvt's dma-buf. The tiling mode, caching
mode and domains can not be changed for this kind of gem object. (Alex)
- change dma-buf related information to be more generic. So other vendor
can use the same interface. (Alex)
v2:
- create a management fd for dma-buf operations. (Alex)
- alloc gem object's backing storage in gem obj's get_pages() callback.
(Chris)
Signed-off-by: Tina Zhang <tina.zhang@intel.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch is to introduce the framebuffer decoder which can decode guest
OS's framebuffer information, including primary, cursor and sprite plane.
v16:
- rebase to 4.14.0-rc6.
v14:
- refine pixel format table. (Zhenyu)
v9:
- move drm format change to a separate patch. (Xiaoguang)
v8:
- fix a bug in decoding primary plane. (Tina)
v7:
- refine framebuffer decoder code. (Zhenyu)
Signed-off-by: Tina Zhang <tina.zhang@intel.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Windows guest driver needs vbt in opregion, to configure the setting
for display. Without opregion support, the display registers won't
be set and this blocks display model to get the correct information
of the guest display plane.
This patch is to provide a virtual opregion for guest. The original
author of this patch is Xiaoguang Chen.
This patch is split from the "Dma-buf support for GVT-g" patch set,
with being rebased to the latest gvt-staging branch.
v3:
- add checking region index during intel_vgpu_rw. (Xiong)
v2:
- refine intel_vgpu_reg_release_opregion. (Xiong)
Here are the previous version comments:
v18:
- unmap vgpu's opregion when destroying vgpu.
v16:
- rebase to 4.14.0-rc6.
Signed-off-by: Bing Niu <bing.niu@intel.com>
Signed-off-by: Tina Zhang <tina.zhang@intel.com>
Tested-by: Xiong Zhang <xiong.y.zhang@intel.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Currently guest opregion is allocated and initialised when guest
write opregion base register. This is too late for kvmgt, so
move it to vgpu_create time.
Signed-off-by: Xiong Zhang <xiong.y.zhang@intel.com>
Tested-by: Tina Zhang <tina.zhang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
More change sets for 4.16:
- Many improvements for selftests and other igt tests (Chris)
- Forcewake with PUNIT->PMIC bus fixes and robustness (Hans)
- Define an engine class for uABI (Tvrtko)
- Context switch fixes and improvements (Chris)
- GT powersavings and power gating simplification and fixes (Chris)
- Other general driver clean-ups (Chris, Lucas, Ville)
- Removing old, useless and/or bad workarounds (Chris, Oscar, Radhakrishna)
- IPS, pipe config, etc in preparation for another Fast Boot attempt (Maarten)
- OA perf fixes and support to Coffee Lake and Cannonlake (Lionel)
- Fixes around GPU fault registers (Michel)
- GEM Proxy (Tina)
- Refactor of Geminilake and Cannonlake plane color handling (James)
- Generalize transcoder loop (Mika Kahola)
- New HW Workaround for Cannonlake and Geminilake (Rodrigo)
- Resume GuC before using GEM (Chris)
- Stolen Memory handling improvements (Ville)
- Initialize entry in PPAT for older compilers (Chris)
- Other fixes and robustness improvements on execbuf (Chris)
- Improve logs of GEM_BUG_ON (Mika Kuoppala)
- Rework with massive rename of GuC functions and files (Sagar)
- Don't sanitize frame start delay if pipe is off (Ville)
- Cannonlake clock fixes (Rodrigo)
- Cannonlake HDMI 2.0 support (Rodrigo)
- Add a GuC doorbells selftest (Michel)
- Add might_sleep() check to our wait_for() (Chris)
Many GVT changes for 4.16:
- CSB HWSP update support (Weinan)
- GVT debug helpers, dyndbg and debugfs (Chuanxiao, Shuo)
- full virtualized opregion (Xiaolin)
- VM health check for sane fallback (Fred)
- workload submission code refactor for future enabling (Zhi)
- Updated repo URL in MAINTAINERS (Zhenyu)
- other many misc fixes
* tag 'drm-intel-next-2017-11-17-1' of git://anongit.freedesktop.org/drm/drm-intel: (260 commits)
drm/i915: Update DRIVER_DATE to 20171117
drm/i915: Add a policy note for removing workarounds
drm/i915/selftests: Report ENOMEM clearly for an allocation failure
Revert "drm/i915: Display WA #1133 WaFbcSkipSegments:cnl, glk"
drm/i915: Calculate g4x intermediate watermarks correctly
drm/i915: Calculate vlv/chv intermediate watermarks correctly, v3.
drm/i915: Pass crtc_state to ips toggle functions, v2
drm/i915: Pass idle crtc_state to intel_dp_sink_crc
drm/i915: Enable FIFO underrun reporting after initial fastset, v4.
drm/i915: Mark the userptr invalidate workqueue as WQ_MEM_RECLAIM
drm/i915: Add might_sleep() check to wait_for()
drm/i915/selftests: Add a GuC doorbells selftest
drm/i915/cnl: Extend HDMI 2.0 support to CNL.
drm/i915/cnl: Simplify dco_fraction calculation.
drm/i915/cnl: Don't blindly replace qdiv.
drm/i915/cnl: Fix wrpll math for higher freqs.
drm/i915/cnl: Fix, simplify and unify wrpll variable sizes.
drm/i915/cnl: Remove useless conversion.
drm/i915/cnl: Remove spurious central_freq.
drm/i915/selftests: exercise_ggtt may have nothing to do
...
Cross-subsystem Changes:
- device tree doc for the Mitsubishi AA070MC01 and Tianma TM070RVHG71
panels (Lukasz Majewski) and for a 2nd endpoint on stm32 (Philippe Cornu)
Core Changes:
The most important changes are:
- Add drm_driver .last_close and .output_poll_changed helpers to reduce
fbdev emulation footprint in drivers (Noralf)
- Fix plane clipping in core and for vmwgfx (Ville)
Then we have a bunch of of improvement for print and debug such as the
addition of a framebuffer debugfs file. ELD connector, HDMI and
improvements. And a bunch of misc improvements, clean ups and style
changes and doc updates
[airlied: drop eld bits from amdgpu_dm]
Driver Changes:
- sii8620: filter unsupported modes and add DVI mode support (Maciej Purski)
- rockchip: analogix_dp: Remove unnecessary init code (Jeffy Chen)
- virtio, cirrus: add fb create_handle support to enable screenshots(Lepton Wu)
- virtio: replace reference/unreference with get/put (Aastha Gupta)
- vc4, gma500: Convert timers to use timer_setup() (Kees Cook)
- vc4: Reject HDMI modes with too high of clocks (Eric)
- vc4: Add support for more pixel formats (Dave Stevenson)
- stm: dsi: Rename driver name to "stm32-display-dsi" (Philippe Cornu)
- stm: ltdc: add a 2nd endpoint (Philippe Cornu)
- via: use monotonic time for VIA_WAIT_IRQ (Arnd Bergmann)
* tag 'drm-misc-next-2017-11-30' of git://anongit.freedesktop.org/drm/drm-misc: (96 commits)
drm/bridge: tc358767: add copyright lines
MAINTAINERS: change maintainer for Rockchip drm drivers
drm/vblank: Fix vblank timestamp debugs
drm/via: use monotonic time for VIA_WAIT_IRQ
dma-buf: Fix ifnullfree.cocci warnings
drm/printer: Add drm_vprintf()
drm/edid: Allow HDMI infoframe without VIC or S3D
video/hdmi: Allow "empty" HDMI infoframes
dma-buf/fence: Fix lock inversion within dma-fence-array
drm/sti: Handle return value of platform_get_irq_byname
drm/vc4: Add support for NV21 and NV61.
drm/vc4: Use .pixel_order instead of custom .flip_cbcr
drm/vc4: Add support for DRM_FORMAT_RGB888 and DRM_FORMAT_BGR888
drm: Move drm_plane_helper_check_state() into drm_atomic_helper.c
drm: Check crtc_state->enable rather than crtc->enabled in drm_plane_helper_check_state()
drm/vmwgfx: Try to fix plane clipping
drm/vmwgfx: Use drm_plane_helper_check_state()
drm/vmwgfx: Remove bogus crtc coords vs fb size check
gpu: gma500: remove unneeded DRIVER_LICENSE #define
drm: don't link DP aux i2c adapter to the hardware device node
...
It has been many years since the last confirmed sighting (and fix) of an
RC6 related bug (usually a system hang). Remove the parameter to stop
users from setting dangerous values, as they often set it during triage
and end up disabling the entire runtime pm instead (the option is not a
fine scalpel!).
Furthermore, it allows users to set known dangerous values which were
intended for testing and not for production use. For testing, we can
always patch in the required setting without having to expose ourselves
to random abuse.
v2: Fixup NEEDS_WaRsDisableCoarsePowerGating fumble, and document the
lack of ilk support better.
v3: Clear intel_info->rc6p if we don't support rc6 itself.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171201113030.18360-1-chris@chris-wilson.co.uk
Previously I was under the impression that the scanline counter
reads 0 when the pipe is off. Turns out that's not correct, and
instead the scanline counter simply stops when the pipe stops, and
it retains it's last value until the pipe starts up again, at which
point the scanline counter jumps to vblank start.
These jumps can cause the timestamp to jump backwards by one frame.
Since we use the timestamps to guesstimage also the frame counter
value on gen2, that would cause the frame counter to also jump
backwards, which leads to a massice difference from the previous value.
The end result is that flips/vblank events don't appear to complete as
they're stuck waiting for the frame counter to catch up to that massive
difference.
Fix the problem properly by actually making sure the scanline counter
has started to move before we assume that it's safe to enable vblank
processing.
v2: Less pointless duplication in the code (Chris)
Cc: stable@vger.kernel.org
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Fixes: b7792d8b54 ("drm/i915: Wait for pipe to start before sampling vblank timestamps on gen2")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171129153732.3612-1-ville.syrjala@linux.intel.com
i830_disable_pipe() gets called from the power well code, and thus
we're already holding the power domain mutex. That means we can't
call plane->get_hw_state() as it will also try to grab the
same mutex and will thus deadlock.
Replace the assert_plane() calls (which calls ->get_hw_state()) with
just raw register reads in i830_disable_pipe(). As a bonus we can
now get a warning if plane C is enabled even though we don't even
expose it as a drm plane.
v2: Do a separate WARN_ON() for each plane (Chris)
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Fixes: 51f5a09639 ("drm/i915: Add .get_hw_state() method for planes")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171129125411.29055-1-ville.syrjala@linux.intel.com