ICL introduces a new gamma correction mode in display engine, called
multi-segmented-gamma mode. This mode allows users to program the
darker region of the gamma curve with sueprfine precision. An
example use case for this is HDR curves (like PQ ST-2084).
If we plot a gamma correction curve from value range between 0.0 to 1.0,
ICL's multi-segment has 3 different sections:
- superfine segment: 9 values, ranges between 0 - 1/(128 * 256)
- fine segment: 257 values, ranges between 0 - 1/(128)
- corase segment: 257 values, ranges between 0 - 1
This patch:
- Changes gamma LUTs size for ICL/GEN11 to 262144 entries (8 * 128 * 256),
so that userspace can program with highest precision supported.
- Changes default gamma mode (non-legacy) to multi-segmented-gamma mode.
- Adds functions to program/detect multi-segment gamma.
V2: Addressed review comments from Ville
- separate function for superfine and fine segments.
- remove enum for segments.
- reuse last entry of the LUT as gc_max value.
- replace if() ....cond with switch...case in icl_load_luts.
- add an entry variable, instead of 'word'
V3: Addressed review comments from Ville
- extra newline
- s/entry/color/
- remove LUT size checks
- program ilk_lut_12p4_ldw value before ilk_lut_12p4_udw
- Change the comments in description of fine and coarse segments,
and try to make more sense.
- use 8 * 128 instead of 1024
- add 1 entry in LUT for GCMAX
V4: Addressed review comments from Ville
- Remove unused macro
- missing shift entry in blue
- pick correct entry for GCMAX
- Added Ville's R-B
Note: Tested and confirmed the programming sequence of odd/even
registers in the HW. The correct sequence should be:
ilk_lut_12p4_udw
ilk_lut_12p4_ldw
v5: Addressed Ville's review comments and renamed odd/even register
helpers to be more consistent with the values.
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Suggested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Shashank Sharma <shashank.sharma@intel.com>
Signed-off-by: Uma Shankar <uma.shankar@intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1560321900-18318-5-git-send-email-uma.shankar@intel.com
Add macros to define multi segmented gamma registers
V2: Addressed Ville's comments:
Add gen-lable before bit definition
Addressed Jani's comment
- Use REG_GENMASK() and REG_BIT()
V3: Addressed Ville's comments:
- Put comments at the end of line.
- Change the comment at start of ICL multisegmented gamma registers.
Added Ville's r-b
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Uma Shankar <uma.shankar@intel.com>
Signed-off-by: Shashank Sharma <shashank.sharma@intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1560321900-18318-3-git-send-email-uma.shankar@intel.com
Currently, data type of gamma_lut_size & degamma_lut_size elements
in intel_device_info is u16, which means it can accommodate maximum
64k values. In case of ICL multisegmented gamma, the size of gamma
LUT is 256K.
This patch changes the data type of both of these elements to u32.
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Uma Shankar <uma.shankar@intel.com>
V4: Added Uma's r-b.
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Signed-off-by: Shashank Sharma <shashank.sharma@intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1560321900-18318-2-git-send-email-uma.shankar@intel.com
Add a new subdirectory for display code, and start off by moving
modesetting output/encoder code. Judging by the include changes, this is
a surprisingly clean operation.
v2:
- move intel_sdvo_regs.h too
- use tabs for Makefile file lists and sort them
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190613084416.6794-2-jani.nikula@intel.com
Ensure intel_sdvo_regs.h is self-contained and remains that way.
v2:
- include <linux/compiler.h> for __packed (Chris)
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190613100818.24800-1-jani.nikula@intel.com
EHL defines two new MOCS table entries but is otherwise compatible with
the ICL MOCS table.
These table entries (16 and 17) should still be considered unused for
ICL and as such their behavior remains undefined for that platform.
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190530234014.22340-1-matthew.d.roper@intel.com
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
While we need to flush the wakeref before parking, we do not need to
perform the i915_gem_park() itself underneath the wakeref lock, merely
the struct_mutex. If we rearrange the locks, we can avoid the unnecessary
tainting.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190614220616.24932-1-chris@chris-wilson.co.uk
To continue the onslaught of removing the assumption of a global
execution ordering, another casualty is the engine->timeline. Without an
actual timeline to track, it is overkill and we can replace it with a
much less grand plain list. We still need a list of requests inflight,
for the simple purpose of finding inflight requests (for retiring,
resetting, preemption etc).
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190614164606.15633-3-chris@chris-wilson.co.uk
We need to keep the context image pinned in memory until after the GPU
has finished writing into it. Since it continues to write as we signal
the final breadcrumb, we need to keep it pinned until the request after
it is complete. Currently we know the order in which requests execute on
each engine, and so to remove that presumption we need to identify a
request/context-switch we know must occur after our completion. Any
request queued after the signal must imply a context switch, for
simplicity we use a fresh request from the kernel context.
The sequence of operations for keeping the context pinned until saved is:
- On context activation, we preallocate a node for each physical engine
the context may operate on. This is to avoid allocations during
unpinning, which may be from inside FS_RECLAIM context (aka the
shrinker)
- On context deactivation on retirement of the last active request (which
is before we know the context has been saved), we add the
preallocated node onto a barrier list on each engine
- On engine idling, we emit a switch to kernel context. When this
switch completes, we know that all previous contexts must have been
saved, and so on retiring this request we can finally unpin all the
contexts that were marked as deactivated prior to the switch.
We can enhance this in future by flushing all the idle contexts on a
regular heartbeat pulse of a switch to kernel context, which will also
be used to check for hung engines.
v2: intel_context_active_acquire/_release
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190614164606.15633-1-chris@chris-wilson.co.uk
Matching the underlying get/put functions.
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190613232156.34940-8-daniele.ceraolospurio@intel.com
The functions where internally already only using the structure, so we
need to just flip the interface.
v2: rebase
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190613232156.34940-7-daniele.ceraolospurio@intel.com
Focusing on the functions called in few places.
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190613232156.34940-6-daniele.ceraolospurio@intel.com
Asserts aside, all the code working on this structure is in
intel_runtime_pm.c and uses the intel_ prefix, so move the
structure to intel_runtime_pm.h and adopt the same prefix.
Since all the asserts are now working on the runtime_pm structure,
bring them across as well.
v2: drop unneeded include (Chris), don't rename debugfs, rebase
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Imre Deak <imre.deak@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190613232156.34940-5-daniele.ceraolospurio@intel.com
With this all the rpm assert-related functions consistently work on
the i915_runtime_pm structure
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190613232156.34940-4-daniele.ceraolospurio@intel.com
Quite a few of the call points have already switched to the version
working directly on the runtime_pm structure, so let's switch over the
rest and kill the i915-based asserts.
v2: rebase
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190613232156.34940-3-daniele.ceraolospurio@intel.com
As a first step towards updating the code to work on the runtime_pm
structure instead of i915, rework all the internals to use and pass
around that.
v2: add comment for kdev (Jani), move rpm init after pdev init for
mock_device
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190613232156.34940-2-daniele.ceraolospurio@intel.com
This chicken bit should be set before enabling FBC to avoid screen
corruption when the plane size has odd vertical and horizontal
dimensions. It is safe to leave the bit set even when FBC is disabled.
v2:
- The bspec's name for this bit on these platforms ("Spare 14") is
pretty meaningless. Let's rename the bit definition to something
that more accurately reflects what the bit really does. (Clint)
v3:
- The chicken register was already defined (along with a few other
gen9-specific bits) farther down. Just add the new bit definition
there. (Clint)
Cc: Clinton Taylor <Clinton.A.Taylor@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190612183631.30540-1-matthew.d.roper@intel.com
Reviewed-by: Clint Taylor <Clinton.A.Taylor@intel.com>
We already use a mutex to serialise i915_reset() and wedging, so all we
need it to link that into i915_request_wait() and we have our lock cycle
detection.
v2.5: Take error mutex for selftests
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190614071023.17929-3-chris@chris-wilson.co.uk
If we enter i915_request_wait() with an already completed request, but
unsignaled dma-fence, signal the fence before returning. This allows us
to execute any of the signal callbacks at the earliest opportunity.
v2: Also signal after busyspin success
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190614111053.25615-2-chris@chris-wilson.co.uk
Since commit a679f58d05 ("drm/i915: Flush pages on acquisition"), we
flush objects on acquire their pages and as such when we create an
object for the purpose of writing into it, we do not need to manually
flush.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.william.auld@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190614111053.25615-1-chris@chris-wilson.co.uk
As the fence registers only apply to regions inside the GGTT is makes
more sense that we track these as part of the i915_ggtt and not the
general mm. In the next patch, we will then pull the register locking
underneath the i915_ggtt.mutex.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190613073254.24048-1-chris@chris-wilson.co.uk
drivers/gpu/drm/i915//gem/i915_gem_shrinker.c:142: warning: Function parameter or member 'shrink' not described in 'i915_gem_shrink'
drivers/gpu/drm/i915//gem/i915_gem_shrinker.c:142: warning: Excess function parameter 'flags' description in 'i915_gem_shrink'
drivers/gpu/drm/i915//intel_display.c:13443: warning: Function parameter or member '_state' not described in 'intel_atomic_check'
drivers/gpu/drm/i915//intel_display.c:13443: warning: Excess function parameter 'state' description in 'intel_atomic_check'
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190612151311.30295-1-chris@chris-wilson.co.uk
Only a few call sites remain which have been converted to uncore mmio
accessors and so the macro can be removed.
ENGINE_POSTING_READ16 is added to replace one engine->mmio_base relative
call site.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190611104548.30545-3-tvrtko.ursulin@linux.intel.com
With async binding, we don't want to manage a bound/unbound list as we
may end up running before we even acquire the pages. All that is
required is keeping track of shrinkable objects, so reduce it to the
minimum list.
Fixes: 6951e5893b ("drm/i915: Move GEM object domain management from struct_mutex to local")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.william.auld@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190612105720.30310-1-chris@chris-wilson.co.uk
All AML parts are either KBL ULX or CFL ULX so there is no point
in keeping INTEL_SUBPLATFORM_AML around. As these are the only
CFL ULX parts (normal CFL didn't have Y SKUs) so we'll just
replace IS_AML_ULX with IS_CFL_ULX (it was already paired with
IS_KBL_ULX which accounts for the other half of the AML parts).
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: José Roberto de Souza <jose.souza@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190605162946.19223-2-ville.syrjala@linux.intel.com
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
On non-ULT HSW the "special" WRPLL reference clock select
actually means non-SSC. Take that into account when reading
out the WRPLL state.
Also the non-SSC reference may be either 24MHz or 135MHz,
which we can read out from FUSE_STRAP3. The BDW docs actually
say: "also indicates whether the CPU and PCH are in a single
package or separate packages", so it may be that this is not
actually required and we could just assume 135 MHz (just like
the code already did). But it doesn't really hurt to read this
out as the HSW docs aren't quite so clear.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190604200933.29417-5-ville.syrjala@linux.intel.com
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Give the PLL control register bits better names on HSW/BDW.
v2: Fix the copy paste fails in SPLL_REF defines (Maarten)
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190610133609.27288-1-ville.syrjala@linux.intel.com
Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> #irc
Our PCH refclk init code currently assumes that the PCH SSC reference
can only be used for FDI. That is not true and it can be used by
SPLL/WRPLL for eDP SSC or clock bending as well. Before we go
reconfiguring it let's make sure no PLL is currently using the PCH
SSC reference.
For some reason the hw is not particularly upset about losing
the clock if we immediately follow up with a modeset. Can't
really explain why nothing times out during the crtc disable
at least, but that's what the logs say. With fastboot the
story is quite different and we lose the entire display if
we turn off the PCH SSC reference when it's still being used.
Since we totally skip configuring the PCH SSC reference it
may not be in the proper state for FDI. Hopefully that won't
be a problem in practice.
We really should move this code to be part of the modeset seqeuence
and properly deal with the potentially conflicting requirements
imposed on PLL reference clocks. But that requires actual work.
Let's toss in a TODO for that.
v2: Pimp the commit message with the fastboot vs. not
details
Cc: Julius B. <freedesktop@blln.gr>
Cc: Johannes Krampf <johannes.krampf@gmail.com>
Tested-by: Johannes Krampf <johannes.krampf@gmail.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=108773
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190604200933.29417-1-ville.syrjala@linux.intel.com
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
We cannot allow ourselves to wait on the GPU while holding any lock as we
may need to reset the GPU. While there is not an explicit lock between
the two operations, lockdep cannot detect the dependency. So let's tell
lockdep about the wait/reset dependency with an explicit lockmap.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190612085246.16374-1-chris@chris-wilson.co.uk
Like was done for ICL, let's convert the voltage level lookup to use
frequency ranges rather than individual frequencies. For deciding the
voltage, the individual value doesn't really matter.
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190610214847.9865-1-lucas.demarchi@intel.com
Like was done for ICL, let's convert the voltage level lookup to use
frequency ranges rather than individual frequencies. For deciding the
voltage, the individual value doesn't really matter.
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190610214834.9789-1-lucas.demarchi@intel.com
Spec shows voltage level 0 as 307.2, 312, or lower and suggests to use
range checks. Prepare for having other frequencies in these ranges by
not comparing the exact frequency.
v2: invert checks by comparing biggest cdclk first (suggested by Ville)
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190610214819.9703-1-lucas.demarchi@intel.com
These functions operate on ggtt so make them take that directly as
parameter.
At the same time move the USES_GUC conditional down to
intel_guc_reserve_ggtt_top for symmetry with
intel_guc_reserved_gtt_size.
v2:
* Rename and move functions to be static in i915_gem_gtt.c (Michal)
v3:
* Add comment explaining reason for reservation, add assert and fix
error message. (Michal)
v4:
* Fix checkpatch error.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190611122350.15060-1-tvrtko.ursulin@linux.intel.com
Reduces pointer chasing and gets more to the point.
v2:
* Tidy whitespace.
* Tidy comment. (Michal)
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Suggested-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190611110044.7742-1-tvrtko.ursulin@linux.intel.com