Commit Graph

279 Commits

Author SHA1 Message Date
Sujaritha Sundaresan 6f25d0be18 drm/i915/guc : GEM_BUG_ON on invoking GuC reset function
Instead of returning -EINVAL, GEM_BUG_ON when GuC reset is invoked for
platforms not supporting as we don't expect to invoke it.

v2: re-wording commit message and subject (Sagar)

Signed-off-by: Sujaritha Sundaresan <sujaritha.sundaresan@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Reviewed-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/1514928025-29659-2-git-send-email-sujaritha.sundaresan@intel.com
2018-01-03 14:02:12 +00:00
Chris Wilson fb6db0f5bf drm/i915: Remove unsafe i915.enable_rc6
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
2017-12-01 15:20:02 +00:00
Hans de Goede bedf4d79c3 drm/i915: Re-register PMIC bus access notifier on runtime resume
intel_uncore_suspend() unregisters the uncore code's PMIC bus access
notifier and gets called on both normal and runtime suspend.

intel_uncore_resume_early() re-registers the notifier, but only on
normal resume. Add a new intel_uncore_runtime_resume() function which
only re-registers the notifier and call that on runtime resume.

Cc: stable@vger.kernel.org
Reported-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171114135518.15981-2-hdegoede@redhat.com
2017-11-15 09:55:12 +01:00
Hans de Goede ce30560c80 drm/i915: Fix false-positive assert_rpm_wakelock_held in i915_pmic_bus_access_notifier v2
assert_rpm_wakelock_held is triggered from i915_pmic_bus_access_notifier
even though it gets unregistered on (runtime) suspend, this is caused
by a race happening under the following circumstances:

intel_runtime_pm_put does:

   atomic_dec(&dev_priv->pm.wakeref_count);

   pm_runtime_mark_last_busy(kdev);
   pm_runtime_put_autosuspend(kdev);

And pm_runtime_put_autosuspend calls intel_runtime_suspend from
a workqueue, so there is ample of time between the atomic_dec() and
intel_runtime_suspend() unregistering the notifier. If the notifier
gets called in this windowd assert_rpm_wakelock_held falsely triggers
(at this point we're not runtime-suspended yet).

This commit adds disable_rpm_wakeref_asserts and
enable_rpm_wakeref_asserts calls around the
intel_uncore_forcewake_get(FORCEWAKE_ALL) call in
i915_pmic_bus_access_notifier fixing the false-positive WARN_ON.

Changes in v2:
-Reword comment explaining why disabling the wakeref asserts is
 ok and necessary

Cc: stable@vger.kernel.org
Reported-by: FKr <bugs-freedesktop@ubermail.me>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171110150301.9601-2-hdegoede@redhat.com
2017-11-15 09:54:53 +01:00
Michel Thierry ce453b3e42 drm/i915: Clear per-engine fault register as early as possible
From gen6, the hardware tracks address lookup failures and we should
clear those registers upon startup to prevent false positives. However,
this was happening before we have the engines defined (intel_uncore_init())
and the for_each_engine loop was just a nop. The earliest we can call
this is inside intel_engines_init_mmio().

Suggested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Michel Thierry <michel.thierry@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171111004448.12360-1-michel.thierry@intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
2017-11-13 19:03:13 +00:00
Hans de Goede a5266db4d3 drm/i915: Acquire PUNIT->PMIC bus for intel_uncore_forcewake_reset()
intel_uncore_forcewake_reset() does forcewake puts and gets as such
we need to make sure that no-one tries to access the PUNIT->PMIC bus
(on systems where this bus is shared) while it runs, otherwise bad
things happen.

Normally this is taken care of by the i915_pmic_bus_access_notifier()
which does an intel_uncore_forcewake_get(FORCEWAKE_ALL) when some other
driver tries to access the PMIC bus, so that later forcewake gets are
no-ops (for the duration of the bus access).

But intel_uncore_forcewake_reset gets called in 3 cases:
1) Before registering the pmic_bus_access_notifier
2) After unregistering the pmic_bus_access_notifier
3) To reset forcewake state on a GPU reset

In all 3 cases the i915_pmic_bus_access_notifier() protection is
insufficient.

This commit fixes this race by calling iosf_mbi_punit_acquire() before
calling intel_uncore_forcewake_reset(). In the case where it is called
directly after unregistering the pmic_bus_access_notifier, we need to
hold the punit-lock over both calls to avoid a race where
intel_uncore_fw_release_timer() may execute between the 2 calls.

Reviewed-by: Imre Deak <imre.deak@intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171019111620.26761-3-hdegoede@redhat.com
2017-11-10 13:14:03 +01:00
Mika Kuoppala 7130630323 drm/i915: Use fallback forcewake if primary ack missing
There is a possibility on gen9 hardware to miss the forcewake ack
message. The recommended workaround is to use another free
bit and toggle it until original bit is successfully acknowledged.

Some future gen9 revs might or might not fix the underlying issue but
using fallback forcewake bit dance can be considered as harmless:
without the ack timeout we never reach the fallback bit forcewake.
Thus as of now we adopt a blanket approach for all gen9 and leave
the bypassing the fallback bit approach for future patches if
corresponding hw revisions do appear.

Commit 83e3337204 ("drm/i915: Increase maximum polling time to 50ms
for forcewake request/clear ack") did increase the forcewake timeout.
If the issue was a delayed ack, future work could include finding
a suitable timeout value both for primary ack and reserve toggle
to reduce the worst case latency.

v2: use bit 15, naming, comment (Chris), only wait fallback ack
v3: fix return on fallback, backoff after fallback write (Chris)
v4: udelay on first pass, grammar (Chris)
v4: s/reserve/fallback

References: HSDES #1604254524
References: https://bugs.freedesktop.org/show_bug.cgi?id=102051
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171102094836.2506-1-mika.kuoppala@linux.intel.com
2017-11-02 12:40:21 +02:00
Michel Thierry 6acbea89ef drm/i915/guc: Add support for reset engine using GuC commands
This patch adds per engine reset and recovery (TDR) support when GuC is
used to submit workloads to GPU.

In the case of i915 directly submission to ELSP, driver manages hang
detection, recovery and resubmission. With GuC submission these tasks
are shared between driver and GuC. i915 is still responsible for detecting
a hang, and when it does it only requests GuC to reset that Engine. GuC
internally manages acquiring forcewake and idling the engine before
resetting it.

Once the reset is successful, i915 takes over again and handles the
resubmission. The scheduler in i915 knows which requests are pending so
after resetting a engine, pending workloads/requests are resubmitted
again.

v2: s/i915_guc_request_engine_reset/i915_guc_reset_engine/ to match the
non-guc function names.

v3: Removed debug message about engine restarting from which request,
since the new baseline do it regardless of submission mode. (Chris)

v4: Rebase.

v5: Do not pass unnecessary reporting flags to the fw (Jeff);
tasklet_schedule(&execlists->irq_tasklet) handles the resubmit; rebase.

v6: Rename the existing reset engine function and share a similar
interface between guc and non-guc paths (Chris).

Signed-off-by: Michel Thierry <michel.thierry@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171031225309.10888-1-michel.thierry@intel.com
Reviewed-by: Jeff McGee <jeff.mcgee@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
2017-11-02 08:42:11 +00:00
Michel Thierry cb20a3c056 drm/i915/guc: Rename the function that resets the GuC
intel_guc_reset sounds more like the microcontroller is the one performing
a reset, while in this case is the opposite. intel_reset_guc not only
makes it clearer, it follows the other intel_reset functions available.

v2: Print error message in English (Tvrtko).

Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: Michel Thierry <michel.thierry@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171030185616.32836-2-michel.thierry@intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
2017-11-02 08:08:05 +00:00
Chris Wilson 11caf5517c drm/i915: Empty the ring before disabling
An interesting snippet from Sandybridge's prm:

"Although a Ring Buffer can be enabled in the non-empty state, it must
not be disabled unless it is empty. Attempting to disable a Ring Buffer
in the non-empty state is UNDEFINED."

Let's avoid the undefined behaviour as we disable the rings prior to
reset and resume.

v2: Tell HEAD to catch up to TAIL (empty ring) first, then reset both to
0 (supposedly while stopped).

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/20171027094311.30380-1-chris@chris-wilson.co.uk
2017-10-27 12:09:29 +01:00
Chris Wilson 5896a5c8c9 drm/i915: Always stop the rings before a missing GPU reset
Always try to stop the rings, even if the GPU reset itself has been
disabled (via modparam i915.reset). This should at least stop the hw
from spinning in the background consuming resources (e.g. power and
memory bandwidth) letting the system rest-in-peace.

References: https://bugs.freedesktop.org/show_bug.cgi?id=103260
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171013131218.18013-2-chris@chris-wilson.co.uk
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
2017-10-13 20:57:29 +01:00
Chris Wilson 67e6456485 drm/i915: Provide an assert for when we expect forcewake to be held
Add assert_forcewakes_active() (the complementary function to
assert_forcewakes_inactive) that documents the requirement of a
function for its callers to be holding the forcewake ref (i.e. the
function is part of a sequence over which RC6 must be prevented).

One such example is during ringbuffer reset, where RC6 must be held
across the whole reinitialisation sequence.

v2: Include debug information in the WARN so we know which fw domain is
missing.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com> #v1
Link: https://patchwork.freedesktop.org/patch/msgid/20171009110301.21705-5-chris@chris-wilson.co.uk
2017-10-09 17:07:29 +01:00
Michal Wajdeczko 4f044a88a8 drm/i915: Rename global i915 to i915_modparams
Our global struct with params is named exactly the same way
as new preferred name for the drm_i915_private function parameter.
To avoid such name reuse lets use different name for the global.

v5: pure rename
v6: fix

Credits-to: Coccinelle

@@
identifier n;
@@
(
-	i915.n
+	i915_modparams.n
)

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Ville Syrjala <ville.syrjala@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Acked-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170919193846.38060-1-michal.wajdeczko@intel.com
2017-09-22 14:50:36 +03:00
Mika Kuoppala 87de8d5613 drm/i915: Stop engines before reset
On kbl evidence indicates that even if the hardware happily
tells us to proceed with reset, it really isn't ready.
Resetting a freely running batchbuffer after we have ack for readiness,
still can cause a system hang.

We also have similar experiences on older gens. So now
attempt to stop engines before proceeding for reset, on all
gens where we have a gpu reset. This has shown to improve reset
reliability and reduce the risk of losing the machine.

v2: Add fixme for wa (Joonas)

Testcase: igt/prime_busy/hang-* # kbl
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170919144128.25506-1-mika.kuoppala@intel.com
2017-09-20 13:56:05 +03:00
Joonas Lahtinen 3fd3a6ffe2 drm/i915: Simplify i915_reg_read_ioctl
Convert to use the freshly available made INTEL_GEN_MASK for easier
grepping and improve function readability and clarify the UABI
documentation.

No functional changes.

v2:
- Lift GEM_BUG_ONs and use is_power_of_2 (Chris)
- Retain -EINVAL on bad flags behavior (Chris)

v3:
- Extract flags with 'entry->size - 1' (Chris)

v4:
- Add GEM_BUG_ON on for flags vs entry offset (Chris)

v5:
- Use 'u16' to match 'dev_priv' (Ville)

v6:
- Fix checkpatch.pl errors

Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20170913115255.13851-2-joonas.lahtinen@linux.intel.com
2017-09-14 11:15:52 +03:00
Chris Wilson d7a133d886 drm/i915: Disable mmio debugging during user access
If the user bypasses i915 and accesses mmio directly, that easily
confuses our automatic mmio debugging (any error we then detect is
likely to be as a result of the user). Since we expect userspace to open
debugfs/i915_forcewake_user if i915.ko is loaded and they want mmio
access, that makes the opportune time to disable our debugging for
duration of the bypass.

v2: Move the fiddling of uncore internals to uncore.c

References: https://bugs.freedesktop.org/show_bug.cgi?id=102543
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/20170907134441.12881-1-chris@chris-wilson.co.uk
2017-09-07 17:58:17 +01:00
Nanley Chery f1294585d8 drm/i915/cnl: Allow the reg_read ioctl to read the RCS TIMESTAMP register
This enables the Mesa driver to advertise support for ARB_timer_query, and
thus an OpenGL version higher than 3.2.

Suggested-by: Ben Widawsky <ben@bwidawsk.net>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Nanley Chery <nanley.g.chery@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/20170905184507.30046-1-nanley.g.chery@intel.com
2017-09-06 12:31:27 -07:00
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
Rodrigo Vivi 3d16ca5890 drm/i915/cnl: Add force wake for gen10+.
By spec there is no change on force wake registers
for Cannonlake. Let's reuse gen9 one.

v2: Adding missing case for the write part. (Tvrtko)
v3: Rebase on recent tree.
v4: Make it for gen9+ instead adding gen10 only. (by Joonas).

Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1499302831-17773-1-git-send-email-rodrigo.vivi@intel.com
2017-07-06 13:22:37 -07:00
Michel Thierry 142bc7d99b drm/i915: Modify error handler for per engine hang recovery
This is a preparatory patch which modifies error handler to do per engine
hang recovery. The actual patch which implements this sequence follows
later in the series. The aim is to prepare existing recovery function to
adapt to this new function where applicable (which fails at this point
because core implementation is lacking) and continue recovery using legacy
full gpu reset.

A helper function is also added to query the availability of engine
reset. A subsequent patch will add the capability to query which type
of reset is present (engine -> full -> no-reset) via the get-param
ioctl.

It has been decided that the error events that are used to notify user of
reset will only be sent in case if full chip reset. In case of just
single (or multiple) engine resets, userspace won't be notified by these
events.

Note that this implementation of engine reset is for i915 directly
submitting to the ELSP, where the driver manages the hang detection,
recovery and resubmission. With GuC submission these tasks are shared
between driver and firmware; i915 will still responsible for detecting a
hang, and when it does it will have to request GuC to reset that Engine and
remind the firmware about the outstanding submissions. This will be
added in different patch.

v2: rebase, advertise engine reset availability in platform definition,
add note about GuC submission.
v3: s/*engine_reset*/*reset_engine*/. (Chris)
Handle reset as 2 level resets, by first going to engine only and fall
backing to full/chip reset as needed, i.e. reset_engine will need the
struct_mutex.
v4: Pass the engine mask to i915_reset. (Chris)
v5: Rebase, update selftests.
v6: Rebase, prepare for mutex-less reset engine.
v7: Pass reset_engine mask as a function parameter, and iterate over the
engine mask for reset_engine. (Chris)
v8: Use i915.reset >=2 in has_reset_engine; remove redundant reset
logging; add a reset-engine-in-progress flag to prevent concurrent
resets, and avoid dual purposing of reset-backoff. (Chris)
v9: Support reset of different engines in parallel (Chris)
v10: Handle reset-engine flag locking better (Chris)
v11: Squash in reporting of per-engine-reset availability.

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Signed-off-by: Ian Lister <ian.lister@intel.com>
Signed-off-by: Tomas Elf <tomas.elf@intel.com>
Signed-off-by: Arun Siluvery <arun.siluvery@linux.intel.com>
Signed-off-by: Michel Thierry <michel.thierry@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170615201828.23144-4-michel.thierry@intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20170620095751.13127-5-chris@chris-wilson.co.uk
2017-06-20 21:00:11 +01:00
Kai Chen d8197317f1 drm/i915: Remove decoupled MMIO code
This is a follow-up patch to the previous patch ([PATCH[1/2] drm/i915:
Disable decoupled MMIO) to remove the dead code for decoupled MMIO
implementation, as it won't be used any longer on GEN9LP.

Therefore, this patch reverts:

commit 85ee17ebee
Author: Praveen Paneri <praveen.paneri@intel.com>
Date:   Tue Nov 15 22:49:20 2016 +0530

    drm/i915/bxt: Broxton decoupled MMIO

Signed-off-by: Kai Chen <kai.chen@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170523215812.18328-3-kai.chen@intel.com
2017-05-30 09:59:41 +03:00
Chris Wilson c9e0c6da53 drm/i915: Keep the forcewake timer alive for 1ms past the most recent use
Currently the timer is armed for 1ms after the first use and is killed
immediately, dropping the forcewake as early as possible. However, for
very frequent operations the forcewake dance has a large impact on
latency and keeping the timer alive until we are idle is preferred. To
achieve this, if we call intel_uncore_forcewake_get whilst the timer is
alive (repeated use), then set a flag to restart the timer on expiry
rather than drop the forcewake usage count. The timer is racy, the
consequence of the race is to expire the timer earlier than is now
desired but does not impact on correct behaviour. The offset the race
slightly, we set the active flag again on intel_uncore_forcewake_put.

The effect should be to reduce the jitter of reacquiring the fw every
1ms on a busy system. However, the cost is to keep the timer alive for
an extra 1ms on a nearly idle system. We chose to incur the jitter
previously to keep the timer off for as much as possible.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170526132209.14640-1-chris@chris-wilson.co.uk
2017-05-26 15:58:21 +01:00
Mika Kuoppala 48f1fc3a30 drm/i915/g33: Improve reset reliability
We improved the reset reliablity on gen4 with
stopping all engines before commencing reset, in
commit 2c80353f3c ("drm/i915/g4x: Improve gpu reset reliability")

Evidence indicates that this same trick works with g33.

v2: proper gen naming, comment readability (Chris)

Testcase: igt/gem_busy/*-hang #blb-e6850
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tomi Sarvela <tomi.p.sarvela@intel.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20170522090244.2557-1-mika.kuoppala@intel.com
2017-05-22 13:34:03 +03:00
Mika Kuoppala 2c80353f3c drm/i915/g4x: Improve gpu reset reliability
ELK seems to very picky about the preconditions to reset.
Evidence on Eaglelake (8086:2e12 (rev 03)) shows that it does
not like if reset occurs when there is active ring.

Ville found out that there is workaround with name
'WaMediaResetMainRingCleanup' which suggests that we need to
cleanup rings before resetting. It is unclear what cleanup
exactly means but evidence shows that stopping the ring
does have an effect on reset reliability. This patch makes
reset successful on hangs induced by chained batches (the igt ones).
Note that if the hang is inside a shader, it is possible
that our attempts to stop the ring achieves anything.

v2: zero ctl,head,tail also. bug ref. use driver debugs (Chris)
v3: specify platform on testcases, comment tidyup (Chris)

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=100942
Testcase: igt/gem_busy/*-hang #elk
Testcase: igt/gem_ringfill/hang-* #elk
Suggested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tomi Sarvela <tomi.p.sarvela@intel.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20170519091340.21439-1-mika.kuoppala@intel.com
2017-05-19 13:59:09 +03:00
Chris Wilson 44e1e7baa3 drm/i915: Reorder media/render reset on g4x
Ville found a reference to WaMediaResetBeforeFullReset which we presume
means that we should simply do the media reset first.

References: https://bugs.freedesktop.org/show_bug.cgi?id=100942
Suggested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170518204811.7408-2-chris@chris-wilson.co.uk
2017-05-18 21:57:18 +01:00
Chris Wilson 9593a6576f drm/i915: Try harder to reset the GPU
Repeat the reset a couple of times if at first we do not succeed.

v2: differentiate which path/engine failed with a debug message

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20170513083726.502-1-chris@chris-wilson.co.uk
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170518204811.7408-1-chris@chris-wilson.co.uk
2017-05-18 21:57:17 +01:00
Daniel Vetter ff26ffa8ee drm/i915: Fix __intel_wait_for_register_fw to not sleep in atomic
The unconditionally fallback to the blocking wait_for resulted in
impressive fireworks at boot-up on my snb here. Make sure if we set
the slow timeout to 0 that we never ever sleep. The tail of the
callchain was

intel_wait_for_register
-> __intel_wait_for_register_fw
  -> usleep_range
     -> BOOM

It blew up in intel_crt_detect load detection code on the
ADPA_CRT_HOTPLUG_FORCE_TRIGGER in the ADPA register.

v2: Shut up gcc.

v3: Use uninitialized_var() (Chris).

Fixes: 0564654340 ("drm/i915: Acquire uncore.lock over intel_uncore_wait_for_register()")
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1494429572-15118-1-git-send-email-daniel.vetter@ffwll.ch
2017-05-10 20:06:41 +02:00
Michal Wajdeczko 16586fcd86 drm/i915: Move uncore definitions into a separate header
In order to allow use of e.g. forcewake_domains in a other feature headers
included from the top of i915_drv.h, move all uncore related definitions
into their own header.

v2: move __mask_next_bit macro to utils header (Mika)

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Suggested-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
2017-05-09 16:02:47 +03:00
Mika Kuoppala 6b07b6d2bd drm/i915: Use wait_for_atomic_us when waiting for gt fifo
Replace the handcrafter loop when checking for fifo slots
with atomic wait for. This brings this wait in line with
the other waits on register access. We also get a readable
timeout constraint, so make it to fail after 10ms.

Chris suggested that we should fail silently as the fifo debug
handler, now attached to unclaimed mmio handling, will take care of the
possible errors at later stage.

Note that the decision to wait was changed so that we avoid
allocating the first reserved entry. Nor do we reduce the count
if we fail the wait, removing the possiblity to wrap the
count if the hw fifo returned zero.

v2: remove unclaimed check on timeout (Chris)
v3: use void return (Chris)

References: https://bugs.freedesktop.org/show_bug.cgi?id=100247
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1491493182-31540-1-git-send-email-mika.kuoppala@intel.com
2017-05-03 12:47:33 +03:00
Mika Kuoppala a338908c11 drm/i915: Move the GTFIFODBG to the common mmio dbg framework
Remove the per-mmio checking of the FIFO debug register into the common
conditional mmio debug handling. Based on patch from Chris Wilson.

v2: postpone warn on fifodbg for unclaimed reg debugs

Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
2017-05-03 12:47:27 +03:00
Tvrtko Ursulin a3662830e1 drm/i915/guc: Fix sleep under spinlock during reset
Looks like intel_guc_reset had the ability to sleep under the
uncore spinlock since forever but it wasn't detected until the
recent changes annotated the wait for register with might_sleep.

I have fixed it by removing holding of the uncore spinlock over
the call to gen6_hw_domain_reset, since I do not see that is
really needed. But there is always a possibility I am missing
some nasty detail so please double check.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Arkadiusz Hiler <arkadiusz.hiler@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Oscar Mateo <oscar.mateo@intel.com>
Acked-by: Michel Thierry <michel.thierry@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
2017-04-28 08:58:15 +01:00
Michel Thierry e3895af8bb drm/i915: Rename gen8_(un)request_engine_reset to gen8_reset_engine_start/cancel
As all other functions related to resetting engines are using
reset_engine.

v2: remove _request_ and use start/cancel instead (Chris)

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Michel Thierry <michel.thierry@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170418202335.35232-3-michel.thierry@intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
2017-04-27 09:11:34 +01:00
Chris Wilson 0757ac8fc7 drm/i915: Add stub mmio read/write routines to mock device
Provide dummy function pointers for the mock device in case we do hit
mmio during testing.

v2: Use ASSIGN_READ/WRITE_MMIO_FUNCS macros

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170412092143.3822-1-chris@chris-wilson.co.uk
2017-04-12 13:37:02 +01:00
Chris Wilson 0564654340 drm/i915: Acquire uncore.lock over intel_uncore_wait_for_register()
We acquire the forcewake and use I915_READ_FW instead for the atomic
wait within intel_uncore_wait_for_register. However, this still leaves
us vulnerable to concurrent mmio access to the register, which can cause
system hangs on gen7. The protection is to acquire uncore.lock around
each register, so lets add it back.

v2: Wrap __intel_wait_for_register_fw() to re-use its atomic wait_for
loop and spare adding another for ourselves.
v3: Add might_sleep() annotation

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170411101340.31994-3-chris@chris-wilson.co.uk
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
2017-04-11 12:44:34 +01:00
Chris Wilson 84d84cb7e2 drm/i915: Stop second guessing the caller for intel_uncore_wait_for_register()
Allow the caller to use the fast_timeout_us to specify how long to wait
within the atomic section, rather than transparently switching to a
sleeping loop for larger values. This is required as some callsites may
need a long wait and are in an atomic section.

v2: Reinforce kerneldoc fast_timeout_us limit with a GEM_BUG_ON

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170411112705.12656-1-chris@chris-wilson.co.uk
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
2017-04-11 12:43:37 +01:00
Michal Wajdeczko 6976e74b5f drm/i915: Don't allow overuse of __intel_wait_for_register_fw()
This function should not be called with long timeouts in atomic context.
Annotate it as might_sleep if timeout is longer than 10us.

v2: fix comment (Michal)

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Suggested-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20170410121747.209200-1-michal.wajdeczko@intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
2017-04-10 15:24:52 +01:00
Michal Wajdeczko 3fc7d86b32 drm/i915: Drop const qualifiers from params in wait_for_register()
These params are passed by value, const qualifiers are ignored any way.
While around, unify timeout_ms type from long to int.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Suggested-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20170410093817.151280-1-michal.wajdeczko@intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
2017-04-10 14:05:28 +01:00
Michal Wajdeczko 1d1a9774e4 drm/i915: Extend intel_wait_for_register_fw() with fast timeout
In some cases we may want to spend more time in atomic wait than
hardcoded 2us. Let's add additional fast timeout parameter to allow
flexible configuration of atomic timeout before switching into heavy wait.
Add also possibility to return registry value to avoid extra read.

v2: use explicit fast timeout (Tvrtko/Chris)
    allow returning register value (Chris)

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Suggested-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20170407160145.181328-1-michal.wajdeczko@intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
2017-04-07 18:48:08 +01:00
Michal Wajdeczko d769ab1827 drm/i915: Fix type of timeout_ms parameter in intel_wait_for_register_fw()
There is no need to specify timeout as unsigned long since this parameter
will be consumed by usecs_to_jiffies() which expects unsigned int only.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170407133212.174608-1-michal.wajdeczko@intel.com
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
2017-04-07 15:59:10 +01:00
Chris Wilson 6e3955a5af drm/i915: All fw_domains share the same set/clear/reset values
Since we reuse the same values for each fw_domain, move them onto
uncore.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170323101944.21627-6-chris@chris-wilson.co.uk
2017-03-23 10:22:04 +00:00
Chris Wilson 0f966aaf5f drm/i915: Remove posting-read for forcewake put
We can relax the requirement upon ourselves that the forcewake is
released immediately and just allow it to occur naturally following our
mmio request.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170323101944.21627-5-chris@chris-wilson.co.uk
2017-03-23 10:22:03 +00:00
Chris Wilson d2dc94bce2 drm/i915: Skip unused fw_domains
Use find-first-set bitop to quickly scan through the fw_domains mask and
skip iterating over unused domains.

v2: Move the WARN into the caller, to prevent compiler warnings in
normal builds.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170323101944.21627-4-chris@chris-wilson.co.uk
2017-03-23 10:22:02 +00:00
Chris Wilson cb3600db6e drm/i915: Use correct fw_domains during reset
In the next patch we will begin to sanity check that we do not attempt
to obtain the forcewake on an unsupport domain. However, that is exactly
what we do during reset of the fw_domains - rectify it before it explodes.

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: http://patchwork.freedesktop.org/patch/msgid/20170323101944.21627-3-chris@chris-wilson.co.uk
2017-03-23 10:22:01 +00:00
Chris Wilson bd52750485 drm/i915: Use correct fw_domains during initialisation
In the next patch we will begin to sanity check that we do not attempt
to obtain the forcewake on an unsupport domain. However, that is exactly
what we do during our actual initialisation of fw_domains - rectify it
before it explodes.

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: http://patchwork.freedesktop.org/patch/msgid/20170323101944.21627-2-chris@chris-wilson.co.uk
2017-03-23 10:22:00 +00:00
Chris Wilson 577ac4bd4c drm/i915: Eliminate per-fw_domain i915 backpointer
Pass along the drm_i915_private pointer from the caller, rather than
looking it up from each fw_domain during fw_domains_get/_put. This
allows us to then eliminate the backpointer, in exchange for a more
complicated unwrapping procedure in the rare
intel_uncore_fw_release_timer().

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170323101944.21627-1-chris@chris-wilson.co.uk
2017-03-23 10:21:59 +00:00
Tvrtko Ursulin e3b1895fc1 drm/i915/vgpu: Neuter forcewakes for VGPU more thoroughly
If we avoid initializing forcewake domains when running as
a guest, and also use gen2 mmio accessors in that case, we
can avoid the timer traffic and any looping through the
forcewake code which is currently just so it can end up in
the no-op forcewake implementation.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Weinan Li <weinan.z.li@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: Terrence Xu <terrence.xu@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170310095747.12258-1-tvrtko.ursulin@linux.intel.com
[tursulin: commit spelling fix]
2017-03-17 09:52:57 +00:00
Daniel Vetter f103560cf7 Merge tag 'topic/designware-baytrail-2017-03-02' of git://anongit.freedesktop.org/git/drm-intel into drm-intel-next-queued
Baytrail PMIC vs. PMU race fixes from Hans de Goede

This time the right version (v4), with the compile fix.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
2017-03-13 09:26:06 +01:00
Tvrtko Ursulin b847305080 drm/i915: Fix forcewake active domain tracking
In commit 003342a500 ("drm/i915: Keep track of active
forcewake domains in a bitmask") I forgot to adjust the
newly introduce fw_domains_active state across reset.

This caused the assert_forcewakes_inactive to trigger
during suspend and resume if there were user held
forcewakes.

v2: Bitmask checks are required since vfuncs are not
    always present.

v3: Move bitmask tracking to get/put vfunc for simplicity.
    (Chris Wilson)

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Fixes: 003342a500 ("drm/i915: Keep track of active forcewake domains in a bitmask")
Testcase: igt/drv_suspend/forcewake
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: "Paneri, Praveen" <praveen.paneri@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: intel-gfx@lists.freedesktop.org
Cc: v4.10+ <stable@vger.kernel.org>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20170310093249.4484-1-tvrtko.ursulin@linux.intel.com
2017-03-10 11:49:20 +00:00
Chris Wilson 675204153e drm/i915: s/assert_spin_locked/lockdep_assert_held/
assert_spin_locked() becomes an unconditionally compiled BUG_ON(),
adding debug code right into the heart of critical routines like
interrupt handlers.

   text	   data	    bss	    dec	    hex
1296480	  19944	   2272	1318696	 141f28	before (lockdep disabled)
1295984	  19944	   2272	1318200	 141d38	after

1336261	  21139	   3208	1360608	 14c2e0	before (lockdep enabled)
1339920	  21139	   3208	1364267	 14d12b	after

Small saving for release; hopefully more instructive in debug.

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>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302132801.599-1-chris@chris-wilson.co.uk
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
2017-03-02 15:18:55 +00:00
Hans de Goede 264ec1a822 drm/i915: Listen for PMIC bus access notifications
Listen for PMIC bus access notifications and get FORCEWAKE_ALL while
the bus is accessed to avoid needing to do any forcewakes, which need
PMIC bus access, while the PMIC bus is busy:

This fixes errors like these showing up in dmesg, usually followed
by a gfx or system freeze:

[drm:fw_domains_get [i915]] *ERROR* render: timed out waiting for forcewake ack request.
[drm:fw_domains_get [i915]] *MEDIA* render: timed out waiting for forcewake ack request.
i2c_designware 808622C1:06: punit semaphore timed out, resetting
i2c_designware 808622C1:06: PUNIT SEM: 2
i2c_designware 808622C1:06: couldn't acquire bus ownership

Downside of this approach is that it causes wakeups whenever the PMIC
bus is accessed. Unfortunately we cannot simply wait for the PMIC bus
to go idle when we hit a race, as forcewakes may be done from interrupt
handlers where we cannot sleep to wait for the i2c PMIC bus access to
finish.

Note that the notifications and thus the wakeups will only happen on
baytrail / cherrytrail devices using PMICs with a shared i2c bus for
P-Unit and host PMIC access (i2c busses with a _SEM method in their
APCI node), e.g. an axp288 PMIC.

I plan to write some patches for drivers accessing the PMIC bus to
limit their bus accesses to a bare minimum (e.g. cache registers, do not
update battery level more often then 4 times a minute), to limit the
amount of wakeups.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=155241
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Tested-by: tagorereddy <tagore.chandan@gmail.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
[danvet: Wiggle in conflicts.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2017-03-02 15:46:37 +01:00