Commit Graph

692700 Commits

Author SHA1 Message Date
Chris Wilson 3ffff01749 drm/i915: Ignore duplicate VMA stored within the per-object handle LUT
By using drm_gem_flink/drm_gem_open on an object using the same fd, it
is possible for a client to create multiple handles pointing to the same
object (tied to the same contexts and VMA), as exemplified by
igt::gem_handle_to_libdrm_bo(). Since this duplication has been possible
since forever, we cannot assume that the handle:(fpriv, object) is
unique and so must handle the multiple users of a single VMA.

v2: Added commentary noise.

Testcase: igt/gem_close
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=102355
Fixes: d1b48c1e71 ("drm/i915: Replace execbuf vma ht with an idr")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170822110517.22277-3-chris@chris-wilson.co.uk
Tested-by: Marta Lofstedt <marta.lofstedt@intel.com>
Reviewed-by: Michał Winiarski <michal.winiarski@intel.com>
2017-08-24 15:28:05 +01:00
Chris Wilson 67b4804025 drm/i915: Assert that the handle->vma lut is empty on object close
Make sure that we are not leaking an entry in the ctx->handles_lut by
asserting that the object was removed prior to being freed. This should
be enforced by all such handles being removed by i915_gem_close_object.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20170822110517.22277-2-chris@chris-wilson.co.uk
Reviewed-by: Michał Winiarski <michal.winiarski@intel.com>
2017-08-24 15:22:46 +01:00
Chris Wilson 432295d7b9 drm/i915: Assert the context is not closed on object-close
During the context-close, we should be decoupling all the vma from the
object so that upon object-closing we shouldn't see any vma from the
already closed contexts. So include a check upon closing the object that
the context is still open.

v2: Eek, the fpriv check is required for shared objects. Double eek, BAT
passed?

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20170822110517.22277-1-chris@chris-wilson.co.uk
Reviewed-by: Michał Winiarski <michal.winiarski@intel.com>
2017-08-24 15:22:21 +01:00
Rodrigo Vivi acfb5554c7 drm/i915/cnl: WaForceContextSaveRestoreNonCoherent
To avoid a potential hang condition with TLB invalidation
we need to enable masked bit 5 of MMIO 0xE5F0 at boot.

Same workaround was in place for previous platforms,
but the register offset has changed for CNL.
But also BSpec doesn't mention the bit 15 as set on gen9
platforms and mark bit as reserved on CNL.

v2: Improve commit message accepting Oscar's suggestion.

Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Oscar Mateo <oscar.mateo@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Oscar Mateo <oscar.mateo@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170823203504.10012-1-rodrigo.vivi@intel.com
2017-08-23 14:35:11 -07:00
Oscar Mateo 2cbecff412 drm/i915/cnl: WaPushConstantDereferenceHoldDisable
CS sometimes hangs on 3D Push Constant dispatches with the new
deref enhancement logic in CNL.

v2: Improve the commit message (Rodrigo)

Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1503518191-19116-1-git-send-email-oscar.mateo@intel.com
2017-08-23 13:31:18 -07:00
Chris Wilson 66df1014ef drm/i915: Keep a small stash of preallocated WC pages
We use WC pages for coherent writes into the ppGTT on !llc
architectures. However, to create a WC page requires a stop_machine(),
i.e. is very slow. To compensate we currently keep a per-vm cache of
recently freed pages, but we still see the slow startup of new contexts.
We can amoritize that cost slightly by allocating WC pages in small
batches (PAGEVEC_SIZE == 14) and since creating a WC page implies a
stop_machine() there is no penalty for keeping that stash global.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170822173828.5932-1-chris@chris-wilson.co.uk
2017-08-22 19:43:00 +01:00
Rodrigo Vivi eb371933cf drm/i915/cfl: Coffee Lake works on Kaby Lake PCH.
Coffee Lake CPU on Kaby Lake PCH is possible.
It does exist, and it does work.

The only missed case was this warning here noticed
by Wendy who could get one system with this configuration
and reported the issue for us:

Hardware Configuration
Board ID KBL S DDR4 UDIMM EV CRB
Processor    Intel® Processor code named Coffee Lake S, (6+2), 6 cores 12 threads, GT2, A0 (Internal) (QNJ4)

[ 3.220585] WARNING: CPU: 10 PID: 206 at drivers/gpu/drm/i915/i915_drv.c:340 i915_driver_load+0x1210/0x1660 [i915]
[ 3.221312] Modules linked in: hid_generic usbhid i915 i2c_algo_bit drm_kms_helper e1000e syscopyarea sysfillrect sysimgblt nvme fb_sys_fops ptp ahci i2c_hid drm pps_core nvme_core libahci wmi hid video
[ 3.222050] CPU: 10 PID: 206 Comm: systemd-udevd Not tainted 4.13.0-rc5-intel-next+ #1
[ 3.222706] Hardware name: Intel Corporation Kabylake Client platform/KBL S DDR4 UDIMM EV CRB, BIOS KBLSE2R1.R00.X089.P00.1705051000 05/05/2017

Cc: Wendy Wang <wendy.wang@intel.com>
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170821235056.9015-1-rodrigo.vivi@intel.com
2017-08-22 11:24:13 -07:00
Paulo Zanoni ade5ee7ea5 drm/i915/cnl: extract cnl_set_procmon_ref_values
Move the part that reads the table and sets registers based on the
table to its own function.

v2: Rebase.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170822000356.17330-2-rodrigo.vivi@intel.com
2017-08-22 09:22:45 -07:00
Paulo Zanoni e0b8acf35d drm/i915/cnl: simplify cnl_procmon_values handling
Make it a little less magical and a little simpler and more hardcoded
so we don't end up with an array that's composed mostly of empty
entries.

v2: Add an enum for the voltage+register values (Ville).

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170822000356.17330-1-rodrigo.vivi@intel.com
2017-08-22 09:22:07 -07:00
Chris Wilson 74d290f845 drm/i915: Boost GPU clocks if we miss the pageflip's vblank
If we miss the current vblank because the gpu was busy, that may cause a
jitter as the frame rate temporarily drops. We try to limit the impact
of this by then boosting the GPU clock to deliver the frame as quickly
as possible. Originally done in commit 6ad790c0f5 ("drm/i915: Boost GPU
frequency if we detect outstanding pageflips") but was never forward
ported to atomic and finally dropped in commit fd3a40242e ("drm/i915:
Rip out legacy page_flip completion/irq handling").

One of the most typical use-cases for this is a mostly idle desktop.
Rendering one frame of the desktop's frontbuffer can easily be
accomplished by the GPU running at low frequency, but often exceeds
the time budget of the desktop compositor. The result is that animations
such as opening the menu, doing a fullscreen switch, or even just trying
to move a window around are slow and jerky. We need to respond within a
frame to give the best impression of a smooth UX, as a compromise we
instead respond if that first frame misses its goal. The result should
be a near-imperceivable initial delay and a smooth animation even
starting from idle. The cost, as ever, is that we spend more power than
is strictly necessary as we overestimate the required GPU frequency and
then try to ramp down.

This of course is reactionary, too little, too late; nevertheless it is
surprisingly effective.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=102199
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170817123706.6777-1-chris@chris-wilson.co.uk
Tested-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Radoslaw Szwichtenberg <radoslaw.szwichtenberg@intel.com>
2017-08-22 17:08:06 +01:00
Ville Syrjälä 5f88a9c619 drm/i915: Constify states passed to enable/disable/etc. encoder hooks
The enable/disable/etc. encoder hooks aren't supposed to alter the
state(s), so pass them as const. Unfortunately C lacks any kind of deep
const thingy, so this can't catch all abuses. But at least it acts as a
hint to the reader telling them not to mess about with the state(s).

v2: Update intel_tv_mode_find() and ironlake_edp_pll_on() as well
v3: Deal with intel_sdvo_connector_state

Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170818134958.15502-9-ville.syrjala@linux.intel.com
2017-08-22 17:59:02 +03:00
Ville Syrjälä d2419ffc10 drm/i915: Plumb crtc_state to PSR enable/disable
The PSR enable/disable need to know things about the crtc state, so
plumb it through. This will become even more important when we start
to reuse the generic infoframe code for the VSC DIP programming as the
infoframe code wants the crtc state as well.

v2: Fix kernel docs

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170818134958.15502-7-ville.syrjala@linux.intel.com
2017-08-22 17:57:46 +03:00
Ville Syrjälä 385e4de0ea drm/i915: Init infoframe vfuncs for DP encoders as well
DP ports may want to use the video DIP for SDP transmission, so let's
initialize the vfuncs for DP encoders as well. The only exception is
port A eDP prior to HSW as that one doesn't have a video DIP instance.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170818134958.15502-6-ville.syrjala@linux.intel.com
2017-08-22 17:57:01 +03:00
Ville Syrjälä f99be1b322 drm/i915: Move infoframe vfuncs into intel_digital_port
DP ports will also want to utilize the video DIP for SDP transmission.
So let's move the vfuncs into the dig_port.

v2: Rebase due to DDI changes

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170818134958.15502-5-ville.syrjala@linux.intel.com
2017-08-22 17:54:23 +03:00
Ville Syrjälä c5f93fcf2e drm/i915: Disable infoframes when shutting down DDI HDMI
Disabling the video DIP when shutting the port down seems like a good
idea.

Bspec says:
"When disabling both the DIP port and DIP transmission,
 first disable the port and then disable DIP."
and
"Restriction : GCP is only supported with HDMI when the bits per color is
 not equal to 8. GCP must be enabled prior to enabling TRANS_DDI_FUNC_CTL
 for HDMI with bits per color not equal to 8 and disabled after disabling
 TRANS_DDI_FUNC_CTL"

So let's do it in the .post_disable() hook.

v2: Remove double "dpms off" caused by rebase fail

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170822140914.24413-1-ville.syrjala@linux.intel.com
2017-08-22 17:53:56 +03:00
Ville Syrjälä b47ef0f793 drm/i915: Check has_infoframes when enabling infoframes
has_infoframe is what tells us whether infoframes should be enabled, so
let's pass that instead of has_hdmi_sink to .set_infoframes().

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170818134958.15502-3-ville.syrjala@linux.intel.com
2017-08-22 17:53:05 +03:00
Michel Thierry 41e61020e8 drm/i915: Re-enable per-engine reset for Broxton
The corruption in CSB mmio reads we were seeing has been tracked down to
incorrectly touching forcewake of all domains, following an engine reset.
It is still a mistery why we only catched this in Broxton, since it
could happen in any platform.

With that fix already merged, commit 4055dc75d6 ("drm/i915: Stop
touching forcewake following a gen6+ engine reset"), lets try to enable
per-engine resets in Broxton one more time.

This reverts commit f188258bde0f ("drm/i915: Disable per-engine reset for
Broxton").

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Michel Thierry <michel.thierry@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170818172342.7282-1-michel.thierry@intel.com
Tested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
2017-08-22 12:27:18 +01:00
Jani Nikula 1853a9daa1 drm/i915/dp: make is_edp non-static and rename to intel_dp_is_edp
Expose across driver for future work. No functional changes.

Cc: Manasi Navare <manasi.d.navare@intel.com>
Cc: Jim Bride <jim.bride@linux.intel.com>
Reviewed-by: Jim Bride <jim.bride@linux.intel.com>
Reviewed-by: Manasi Navare <manasi.d.navare@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170818093020.19160-2-jani.nikula@intel.com
2017-08-21 10:24:01 +03:00
Jani Nikula 7b91bf7f91 drm/i915/dp: rename intel_dp_is_edp to intel_dp_is_port_edp
Emphasize that this is based on the port, not intel_dp. This is also in
line with the underlying intel_bios_is_port_edp() function. No
functional changes.

Cc: Manasi Navare <manasi.d.navare@intel.com>
Cc: Jim Bride <jim.bride@linux.intel.com>
Reviewed-by: Jim Bride <jim.bride@linux.intel.com>
Reviewed-by: Manasi Navare <manasi.d.navare@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170818093020.19160-1-jani.nikula@intel.com
2017-08-21 10:23:28 +03:00
Rodrigo Vivi 1a25db65d3 drm/i915/cnl: Apply large line width optimization
This bit enables hardware that will change the approximation used for distances
calculations for AA wide lines so that they are rendered more accurately.

The default value for this bit leaves the legacy behavior. There is no good
reason to not enable the new approximation except if comparing to previous GEN
rendered images.

v2: Rebase
v3: Fix author.
    Rebased by Rodrigo who also added  a comment as suggested by Oscar.
    Since it is surrounded by Workarounds let's just add a comment to
    make clear it is not an Wa.

Cc: Oscar Mateo <oscar.mateo@intel.com>
Signed-off-by: Ben Widawsky <benjamin.widawsky@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Oscar Mateo <oscar.mateo@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170815231651.975-4-rodrigo.vivi@intel.com
2017-08-18 15:33:13 -07:00
Rodrigo Vivi d1d247543c drm/i915/cnl: WaDisableEnhancedSBEVertexCaching
WA forTDS handle reallocation getting dropped by SDE,
which may result in PS attribute corruption.

Disable enhanced SBE vertex caching in COMMON_SLICE_CHICKEN2 offset.

v2: Make it until B0 as spec tells. (by Mika).

Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Oscar Mateo <oscar.mateo@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170815231651.975-3-rodrigo.vivi@intel.com
2017-08-18 15:32:58 -07:00
Rodrigo Vivi e6d1a4f6b2 drm/i915/cnl: Add WaDisableReplayBufferBankArbitrationOptimization
WA to disable replay buffer destination buffer arbitration optimization.

Same Wa on previous platforms has a different name: WaToEnableHwFixForPushConstHWBug

Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170815231651.975-2-rodrigo.vivi@intel.com
2017-08-18 15:32:34 -07:00
Rodrigo Vivi 90007bca61 drm/i915/cnl: Introduce initial Cannonlake Workarounds.
Let's inherit workarounds from previous platforms that
according to wa_database and BSpec are still valid for
Cannonlake.

v2: Add missed workarounds.
v3: Rebase
v4: Remove bad chunk that was added to rc6 disable. (Ander)
    Also remove A0 W/a that are not needed anymore.
v5: Rebase on top of CFL.
v6: Remove empty gen9_init_perctx_bb and gen9_init_indirectctx_bb
    since they don't carry any gen10 related W/a. (by Oscar).
    Also Remove A0 exclusive workaround.
v7: Remove more A0 exclusive workarounds. As pointed out by Oscar
    many workarounds were changed to be A0 only so let's remove
    them.

Cc: Oscar Mateo <oscar.mateo@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Oscar Mateo <oscar.mateo@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170815231651.975-1-rodrigo.vivi@intel.com
2017-08-18 15:32:17 -07:00
Chris Wilson 64f09f00ca drm/i915: Clear lost context-switch interrupts across reset
During a global reset, we disable the irq. As we disable the irq, the
hardware may be raising a GT interrupt that we then ignore, leaving it
pending in the GTIIR. After the reset, we then re-enable the irq,
triggering the pending interrupt. However, that interrupt was for the
stale state from before the reset, and the contents of the CSB buffer
are now invalid.

v2: Add a comment to make it clear that the double clear is purely my
paranoia.

Reported-by: "Dong, Chuanxiao" <chuanxiao.dong@intel.com>
Fixes: 821ed7df6e ("drm/i915: Update reset path to fix incomplete requests")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: "Dong, Chuanxiao" <chuanxiao.dong@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Michal Winiarski <michal.winiarski@intel.com>
Cc: Michel Thierry <michel.thierry@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170807121919.30165-1-chris@chris-wilson.co.uk
Link: https://patchwork.freedesktop.org/patch/msgid/20170818090509.5363-1-chris@chris-wilson.co.uk
Reviewed-by: Michel Thierry <michel.thierry@intel.com>
2017-08-18 22:42:13 +01:00
Daniel Vetter a42894ebb5 drm/i915: Update DRIVER_DATE to 20170818
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2017-08-18 22:40:45 +02:00
Andy Shevchenko cd55a1fbd2 drm/i915/bxt: use NULL for GPIO connection ID
The commit 213e08ad60
	("drm/i915/bxt: add bxt dsi gpio element support")
enables GPIO support for Broxton based platforms.

While using that API we might get into troubles in the future, because
we can't rely on label name in the driver since vendor firmware might
provide any GPIO pin there, e.g. "reset", and even mark it in _DSD (in
which case the request will fail).

To avoid inconsistency and potential issues we have two options:
a) generate GPIO ACPI mapping table and supply it via
   acpi_dev_add_driver_gpios(), or
b) just pass NULL as connection ID.

The b) approach is much simpler and would work since the driver relies
on GPIO indices only. Moreover, the _CRS fallback mechanism, when
requesting GPIO, has been made stricter, and supplying non-NULL
connection ID when neither _DSD, nor GPIO ACPI mapping is present, is
making request fail.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101921
Fixes: f10e4bf663 ("gpio: acpi: Even more tighten up ACPI GPIO lookups")
Cc: Mika Kahola <mika.kahola@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Tested-by: Mika Kahola <mika.kahola@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170817105541.63914-1-andriy.shevchenko@linux.intel.com
2017-08-18 15:57:51 +03:00
Chris Wilson 636918f130 drm/i915: Mark the GT as busy before idling the previous request
In a synchronous setup, we may retire the last request before we
complete allocating the next request. As the last request is retired, we
queue a timer to mark the device as idle, and promptly have to execute
ad cancel that timer once we complete allocating the request and need to
keep the device awake. If we rearrange the mark_busy() to occur before
we retire the previous request, we can skip this ping-pong.

v2: Joonas pointed out that unreserve_seqno() was now doing more than
doing seqno handling and should be renamed to reflect its wider purpose.
That also highlighted the new asymmetry with reserve_seqno(), so fixup
that and rename both to [un]reserve_engine().

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170817144719.10968-1-chris@chris-wilson.co.uk
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
2017-08-18 12:01:41 +01:00
Chris Wilson 0519bcb173 drm/i915: Trivial grammar fix s/opt of/opt out of/ in comment
The word out was dropped from the sentence across the line break, put it
back.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20170816085210.4199-6-chris@chris-wilson.co.uk
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
2017-08-18 11:59:28 +01:00
Chris Wilson d1b48c1e71 drm/i915: Replace execbuf vma ht with an idr
This was the competing idea long ago, but it was only with the rewrite
of the idr as an radixtree and using the radixtree directly ourselves,
along with the realisation that we can store the vma directly in the
radixtree and only need a list for the reverse mapping, that made the
patch performant enough to displace using a hashtable. Though the vma ht
is fast and doesn't require any extra allocation (as we can embed the node
inside the vma), it does require a thread for resizing and serialization
and will have the occasional slow lookup. That is hairy enough to
investigate alternatives and favour them if equivalent in peak performance.
One advantage of allocating an indirection entry is that we can support a
single shared bo between many clients, something that was done on a
first-come first-serve basis for shared GGTT vma previously. To offset
the extra allocations, we create yet another kmem_cache for them.

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/20170816085210.4199-5-chris@chris-wilson.co.uk
2017-08-18 11:59:02 +01:00
Chris Wilson 170fa29b14 drm/i915: Simplify eb_lookup_vmas()
Since the introduction of being able to perform a lockless lookup of an
object (i915_gem_object_get_rcu() in fbbd37b36f ("drm/i915: Move object
release to a freelist + worker") we no longer need to split the
object/vma lookup into 3 phases and so combine them into a much simpler
single loop.

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/20170816085210.4199-4-chris@chris-wilson.co.uk
2017-08-18 11:58:29 +01:00
Chris Wilson c7c6e46f91 drm/i915: Convert execbuf to use struct-of-array packing for critical fields
When userspace is doing most of the work, avoiding relocs (using
NO_RELOC) and opting out of implicit synchronisation (using ASYNC), we
still spend a lot of time processing the arrays in execbuf, even though
we now should have nothing to do most of the time. One issue that
becomes readily apparent in profiling anv is that iterating over the
large execobj[] is unfriendly to the loop prefetchers of the CPU and it
much prefers iterating over a pair of arrays rather than one big array.

v2: Clear vma[] on construction to handle errors during vma lookup

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/20170816085210.4199-3-chris@chris-wilson.co.uk
2017-08-18 11:57:36 +01:00
Chris Wilson 8bcbfb1281 drm/i915: Check context status before looking up our obj/vma
Since we keep the context around across the slow lookup where we may
drop the struct_mutex, we should double check that the context is still
valid upon reacquisition.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170816085210.4199-2-chris@chris-wilson.co.uk
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
2017-08-18 11:57:13 +01:00
Chris Wilson f2f5c0610f drm/i915: Don't use MI_STORE_DWORD_IMM on Sandybridge/vcs
MI_STORE_DWORD_IMM just doesn't work on the video decode engine under
Sandybridge, so refrain from using it. Then switch the selftests over to
using the now common test prior to using MI_STORE_DWORD_IMM.

Fixes: 7dd4f6729f ("drm/i915: Async GPU relocation processing")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: <drm-intel-fixes@lists.freedesktop.org> # v4.13-rc1+
Link: https://patchwork.freedesktop.org/patch/msgid/20170816085210.4199-1-chris@chris-wilson.co.uk
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
2017-08-18 11:55:02 +01:00
Chris Wilson 4055dc75d6 drm/i915: Stop touching forcewake following a gen6+ engine reset
Forcewake is not affected by the engine reset on gen6+. Indeed the
reason why we added intel_uncore_forcewake_reset() to
gen6_reset_engines() was to keep the bookkeeping intact because the
reset did not touch the forcewake bit (yet we cancelled the forcewake
consumers)!  This was done in commit 521198a2e7095:
    Author: Mika Kuoppala <mika.kuoppala@linux.intel.com>
    Date:   Fri Aug 23 16:52:30 2013 +0300

	drm/i915: sanitize forcewake registers on reset

	In reset we try to restore the forcewake state to
	pre reset state, using forcewake_count. The reset
	doesn't seem to clear the forcewake bits so we
	get warn on forcewake ack register not clearing.

That futzing of the forcewake bookkeeping was dropped in commit
0294ae7b44 ("drm/i915: Consolidate forcewake resetting to a single
function"), but it did not make the realisation that the remaining
intel_uncore_forcewake_reset() was redundant.

The new danger with using intel_uncore_forcewake_reset() with per-engine
resets is that the driver and hw are still in an active state as we
perform the reset. We may be using the forcewake to read protected
registers elsewhere and those results may be clobbered by the concurrent
dropping of forcewake.

Reported-by: Michel Thierry <michel.thierry@intel.com>
Fixes: 142bc7d99b ("drm/i915: Modify error handler for per engine hang recovery")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Michel Thierry <michel.thierry@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170817173229.20324-1-chris@chris-wilson.co.uk
Reviewed-by: Michel Thierry <michel.thierry@intel.com>
Acked-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
2017-08-18 10:05:59 +01:00
Daniel Vetter 7bc66c6ad9 MAINTAINERS: drm/i915 has a new maintainer team
For a bunch of reasons[1] I've decided to step down as maintainer and
let some other folks enjoy the reputation and hang out in the
spotlight.

Jani is going to stick around with his expertise in kms and having
done the fixes flow for a long time now. Joonas will join and bring in
his knowledge on all things GEM. Rodrigo has been less visible because
he's been doing tons of work taking care of the internal branch, and
it'd be good to have more continuity between these two worlds also on
the maintainer side.

1: They all boil down to: This is going to happen sooner or later
anyway, we have a great team, with the process improvements over the
last few years things work rather well, now is as good as any time to
do this. With that change I'll have more time for other aspects of the
stack development than maintainership.

Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Dave Airlie <airlied@gmail.com>
Acked-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Acked-by: Jani Nikula <jani.nikula@linux.intel.com>
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170815160101.1683-1-daniel.vetter@ffwll.ch
2017-08-18 10:17:09 +02:00
Anusha Srivatsa cec3bb013a drm/i915: Split pin mapping into per platform functions
Cleanup the code. Map the pins in accordance to
individual platforms rather than according to ports.
Create separate functions for platforms.

v2:
 - Add missing condition for CoffeeLake. Make platform
 specific functions static. Add function
 i915_ddc_pin_mapping().

v3:
 - Rename functions to x_port_to_ddc_pin() which directly
   indicates the purpose. Correct default return values on CNP
   and BXT. Rename i915_port_to_ to g4x_port_to since that was
   the first platform to run this. Correct code style. (Paulo)

Sugested-by Ville Syrjala <ville.syrjala@linux.intel.com>
Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Clinton Taylor <clinton.a.taylor@intel.com>
Signed-off-by: Anusha Srivatsa <anusha.srivatsa@intel.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1502927114-24012-1-git-send-email-anusha.srivatsa@intel.com
2017-08-17 18:01:39 -03:00
Jani Nikula ab3595bc4f drm/i915/opregion: let user specify override VBT via firmware load
Sometimes it would be most enlightening to debug systems by replacing
the VBT to be used. For example, in the referenced bug the BIOS provides
different VBT depending on the boot mode (UEFI vs. legacy). It would be
interesting to try the failing boot mode with the VBT from the working
boot, and see if that makes a difference.

Add a module parameter to load the VBT using the firmware loader, not
unlike the EDID firmware mechanism.

As a starting point for experimenting, one can pick up the BIOS provided
VBT from /sys/kernel/debug/dri/0/i915_opregion/i915_vbt.

v2: clarify firmware load return value check (Bob)

v3: kfree the loaded firmware blob

References: https://bugs.freedesktop.org/show_bug.cgi?id=97822#c83
Reviewed-by: Bob Paauwe <bob.j.paauwe@intel.com>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170817115209.25912-1-jani.nikula@intel.com
2017-08-17 16:34:54 +03:00
Rodrigo Vivi a029fa4d75 drm/i915/cnl: Reuse skl_wm_get_hw_state on Cannonlake.
Otherwise it reuses the ilk that has a completely different
wm.

Cc: Mahesh Kumar <mahesh1.kumar@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170809205248.11917-6-rodrigo.vivi@intel.com
2017-08-16 07:43:12 -07:00
Paulo Zanoni 6c64dd378a drm/i915/gen10: implement gen 10 watermarks calculations
They're slightly different than the gen 9 calculations.

v2: Remove TODO comment. Code matches recent spec.
v3: Rebase on top of latest skl code using new fp16.16 and
    fixing a logic issue. Auto rebase bot has apparently
    made some bad decisions that changed the logic of the
    code. (Noticed by Manesh, updated by Rodrigo).

Cc: Mahesh Kumar <mahesh1.kumar@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Mahesh Kumar <mahesh1.kumar@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170811233825.32083-1-rodrigo.vivi@intel.com
2017-08-16 07:42:36 -07:00
Rodrigo Vivi acf58d4e96 drm/i915/cnl: Fix LSPCON support.
When LSPCON support was extended to CNL
one part was missed on lspcon_init.

So, instead of adding check per platform on lspcon_init
let's use HAS_LSPCON that is already there for that
purpose.

Fixes: ff15947e0f ("drm/i915/cnl: LSPCON support is gen9+")
Cc: Shashank Sharma <shashank.sharma@intel.com>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170816030403.11368-1-rodrigo.vivi@intel.com
2017-08-16 07:42:00 -07:00
Jani Nikula b5273d7275 drm/i915/vbt: ignore extraneous child devices for a port
Ever since we've parsed VBT child devices, starting from 6acab15a7b
("drm/i915: use the HDMI DDI buffer translations from VBT"), we've
ignored the child device information if more than one child device
references the same port. The rationale for this seems lost in time.

Since commit 311a20949f ("drm/i915: don't init DP or HDMI when not
supported by DDI port") we started using this information more to skip
HDMI/DP init if the port wasn't there per VBT child devices. However, at
the same time it added port defaults without further explanation.

Thus, if the child device info was skipped due to multiple child devices
referencing the same port, the device info would be retrieved from the
somewhat arbitrary defaults.

Finally, when commit bb1d132935 ("drm/i915/vbt: split out defaults
that are set when there is no VBT") stopped initializing the defaults
whenever VBT is present, thus trusting the VBT more, we stopped
initializing ports which were referenced by more than one child device.

Apparently at least Asus UX305UA, UX305U, and UX306U laptops have VBT
child device blocks which cause this behaviour. Arguably they were
shipped with a broken VBT.

Relax the rules for multiple references to the same port, and use the
first child device info to reference a port. Retain the logic to debug
log about this, though.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101745
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=196233
Fixes: bb1d132935 ("drm/i915/vbt: split out defaults that are set when there is no VBT")
Tested-by: Oliver Weißbarth <mail@oweissbarth.de>
Reported-by: Oliver Weißbarth <mail@oweissbarth.de>
Reported-by: Didier G <didierg-divers@orange.fr>
Reported-by: Giles Anderson <agander@gmail.com>
Cc: Manasi Navare <manasi.d.navare@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: <stable@vger.kernel.org> # v4.12+
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170811113907.6716-1-jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2017-08-16 17:40:37 +03:00
Rodrigo Vivi 4e34935fcf drm/i915/cnl: Setup PAT Index.
Different from previous platforms, on CNL+ there's separated
registers for separated indexes.

v2: Remove comments regarding uncertainty around the table.
v3: Remove extra line (by Ben)

Cc: Clint Taylor <clinton.a.taylor@intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Ben Widawsky <benjamin.widawsky@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170815232539.3562-1-rodrigo.vivi@intel.com
2017-08-15 16:57:24 -07:00
Jim Bride dc911f5bd8 drm/i915/edp: Allow alternate fixed mode for eDP if available.
Some fixed resolution panels actually support more than one mode,
with the only thing different being the refresh rate.  Having this
alternate mode available to us is desirable, because it allows us to
test PSR on panels whose setup time at the preferred mode is too long.
With this patch we allow the use of the alternate mode if it's
available and it was specifically requested.

v2 and v3: Rebase
v4: * Fix up some leaky mode stuff (Chris)
    * Rebase
v5: * Fix a NULL pointer derefrence (David Weinehall)
v6: * Whitespace / spelling / checkpatch clean-up; no functional
      change. (David)
    * Rebase

Cc: David Weinehall <david.weinehall@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: David Weinehall <david.weinehall@linux.intel.com>
Signed-off-by: Jim Bride <jim.bride@linux.intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1502308133-26892-1-git-send-email-jim.bride@linux.intel.com
2017-08-15 16:43:33 -07:00
Jason Ekstrand cf6e7bac63 drm/i915: Add support for drm syncobjs
This commit adds support for waiting on or signaling DRM syncobjs as
part of execbuf.  It does so by hijacking the currently unused cliprects
pointer to instead point to an array of i915_gem_exec_fence structs
which containe a DRM syncobj and a flags parameter which specifies
whether to wait on it or to signal it.  This implementation
theoretically allows for both flags to be set in which case it waits on
the dma_fence that was in the syncobj and then immediately replaces it
with the dma_fence from the current execbuf.

v2:
 - Rebase on new syncobj API
v3:
 - Pull everything out into helpers
 - Do all allocation in gem_execbuffer2
 - Pack the flags in the bottom 2 bits of the drm_syncobj*
v4:
 - Prevent a potential race on syncobj->fence

Testcase: igt/gem_exec_fence/syncobj*
Signed-off-by: Jason Ekstrand <jason@jlekstrand.net>
Link: https://patchwork.freedesktop.org/patch/msgid/1499289202-25441-1-git-send-email-jason.ekstrand@intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20170815145733.4562-1-chris@chris-wilson.co.uk
2017-08-15 16:46:57 +01:00
Chris Wilson b805014897 drm/i915: Handle full s64 precision for wait-ioctl
The wait-ioctl is optionally supplied a timeout with nanosecond
precision in a s64 field. We use nsecs_to_jiffies64() to convert that
into the jiffies consumed by the scheduler, but internally
nsecs_to_jiffies64() does not guard against overflow (as it's purpose is
for use by the scheduler and not drivers!). So we must guard against the
overflow ourselves, and in the process note that we may then return
much earlier than the timeout selected by the user, so don't report
ETIME unless we do hit the timeout. (Woe betold us though if the user
waits for a year (32bit) and the request is still not complete!)

v2: Refine overflow detection (to not include an overffow itself)

Reported-by: Jason Ekstrand <jason.ekstrand@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20170811105731.9482-1-chris@chris-wilson.co.uk
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
2017-08-15 16:25:25 +01:00
Chris Wilson b8f55be644 drm/i915: Split obj->cache_coherent to track r/w
Another month, another story in the cache coherency saga. This time, we
come to the realisation that i915_gem_object_is_coherent() has been
reporting whether we can read from the target without requiring a cache
invalidate; but we were using it in places for testing whether we could
write into the object without requiring a cache flush. So split the
tracking into two, one to decide before reads, one after writes.

See commit e27ab73d17 ("drm/i915: Mark CPU cache as dirty on every
transition for CPU writes") for the previous entry in this saga.

v2: Be verbose
v3: Remove unused function (i915_gem_object_is_coherent)
v4: Fix inverted coherency check prior to execbuf (from v2)
v5: Add comment for nasty code where we are optimising on gcc's behalf.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101109
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101555
Testcase: igt/kms_mmap_write_crc
Testcase: igt/kms_pwrite_crc
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Dongwon Kim <dongwon.kim@intel.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Tested-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170811111116.10373-1-chris@chris-wilson.co.uk
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
2017-08-15 15:46:57 +01:00
Imre Deak 9c3a16c887 drm/i915/hsw+: Add support for multiple power well regs
Future platforms increase the number of power wells which require
additional control registers. A convenient way to select the correct
register is to use the high bits of the power well ID as index. This
patch only prepares for this, while upcoming platform enabling patches
will add the actual new power well IDs and corresponding power well
control registers.

Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Animesh Manna <animesh.manna@intel.com>
Cc: Rakshmi Bhatia <rakshmi.bhatia@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Animesh Manna <animesh.manna@intel.com>
Reviewed-by: Rakshmi Bhatia <rakshmi.bhatia@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170814151530.24154-2-imre.deak@intel.com
2017-08-15 15:28:10 +03:00
Imre Deak 0a445945be drm/i915: Work around GCC anonymous union initialization bug
GCC 4.4 can't cope with anonymous union initializers which seems to be a
bug in that version (see the Reference) and is fixed since GCC version
4.6. A workaround which is also used elsewhere in the kernel for the
same purpose is to wrap the initialization in curly braces, so do the
same here.

Fixes: b5565a2efc ("drm/i915/bxt, glk: Give a proper name to the power well struct phy field")
Reference: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=10676
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Cc: Arkadiusz Hiler <arkadiusz.hiler@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20170814151530.24154-1-imre.deak@intel.com
2017-08-15 14:31:52 +03:00
Daniel Vetter baa68f6e5b Merge tag 'gvt-next-2017-08-15' of https://github.com/01org/gvt-linux into drm-intel-next-queued
gvt-next-2017-08-15

gvt update for 4.14
- MMIO save/restore optimization (Changbin)
- Split workload scan vs. dispatch for more parallel exec (Ping)
- vGPU full 48bit ppgtt support (Joonas, Tina)
- vGPU hw id expose for perf (Zhenyu)
- other misc cleanup and fixes

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20170815023940.skhjfcsyrao7axqi@zhen-hp.sh.intel.com
2017-08-15 12:52:39 +02:00
Balasubramaniam, Hari Chand d59814a5b4 drm/i915: Initialize 'data' in intel_dsi_dcs_backlight.c
variable 'data' may be used uninitialized in this function. thus,
'function dcs_get_backlight' will return unwanted value/fail.

Thus, adding NULL initialized to 'data' variable will solve the return
failure happening.

v2: Change commit message to reflect upstream with proper message

Fixes: 90198355b8 ("drm/i915/dsi: Add DCS control for Panel PWM")
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Yetunde Adebisi <yetundex.adebisi@intel.com>
Cc: Deepak M <m.deepak@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Balasubramaniam, Hari Chand <hari.chand.balasubramaniam@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1502762746-191826-1-git-send-email-hari.chand.balasubramaniam@intel.com
2017-08-15 10:48:21 +03:00