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Author SHA1 Message Date
Chris Wilson
6f7ac82853 drm/i915/gt: Save irqstate around virtual_context_destroy
As virtual_context_destroy() may be called from a request signal, it may
be called from inside an irq-off section, and so we need to do a full
save/restore of the irq state rather than blindly re-enable irqs upon
unlocking.

<4> [110.024262] WARNING: inconsistent lock state
<4> [110.024277] 5.4.0-rc8-CI-CI_DRM_7489+ #1 Tainted: G     U
<4> [110.024292] --------------------------------
<4> [110.024305] inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage.
<4> [110.024323] kworker/0:0/5 [HC0[0]:SC0[0]:HE1:SE1] takes:
<4> [110.024338] ffff88826a0c7a18 (&(&rq->lock)->rlock){?.-.}, at: i915_request_retire+0x221/0x930 [i915]
<4> [110.024592] {IN-HARDIRQ-W} state was registered at:
<4> [110.024612]   lock_acquire+0xa7/0x1c0
<4> [110.024627]   _raw_spin_lock_irqsave+0x33/0x50
<4> [110.024788]   intel_engine_breadcrumbs_irq+0x38c/0x600 [i915]
<4> [110.024808]   irq_work_run_list+0x49/0x70
<4> [110.024824]   irq_work_run+0x26/0x50
<4> [110.024839]   smp_irq_work_interrupt+0x44/0x1e0
<4> [110.024855]   irq_work_interrupt+0xf/0x20
<4> [110.024871]   __do_softirq+0xb7/0x47f
<4> [110.024885]   irq_exit+0xba/0xc0
<4> [110.024898]   do_IRQ+0x83/0x160
<4> [110.024910]   ret_from_intr+0x0/0x1d
<4> [110.024922] irq event stamp: 172864
<4> [110.024938] hardirqs last  enabled at (172863): [<ffffffff819ea214>] _raw_spin_unlock_irq+0x24/0x50
<4> [110.024963] hardirqs last disabled at (172864): [<ffffffff819e9fba>] _raw_spin_lock_irq+0xa/0x40
<4> [110.024988] softirqs last  enabled at (172812): [<ffffffff81c00385>] __do_softirq+0x385/0x47f
<4> [110.025012] softirqs last disabled at (172797): [<ffffffff810b829a>] irq_exit+0xba/0xc0
<4> [110.025031]
other info that might help us debug this:
<4> [110.025049]  Possible unsafe locking scenario:

<4> [110.025065]        CPU0
<4> [110.025075]        ----
<4> [110.025084]   lock(&(&rq->lock)->rlock);
<4> [110.025099]   <Interrupt>
<4> [110.025109]     lock(&(&rq->lock)->rlock);
<4> [110.025124]
 *** DEADLOCK ***

<4> [110.025144] 4 locks held by kworker/0:0/5:
<4> [110.025156]  #0: ffff88827588f528 ((wq_completion)events){+.+.}, at: process_one_work+0x1de/0x620
<4> [110.025187]  #1: ffffc9000006fe78 ((work_completion)(&engine->retire_work)){+.+.}, at: process_one_work+0x1de/0x620
<4> [110.025219]  #2: ffff88825605e270 (&kernel#2){+.+.}, at: engine_retire+0x57/0xe0 [i915]
<4> [110.025405]  #3: ffff88826a0c7a18 (&(&rq->lock)->rlock){?.-.}, at: i915_request_retire+0x221/0x930 [i915]
<4> [110.025634]
stack backtrace:
<4> [110.025653] CPU: 0 PID: 5 Comm: kworker/0:0 Tainted: G     U            5.4.0-rc8-CI-CI_DRM_7489+ #1
<4> [110.025675] Hardware name:  /NUC7i5BNB, BIOS BNKBL357.86A.0054.2017.1025.1822 10/25/2017
<4> [110.025856] Workqueue: events engine_retire [i915]
<4> [110.025872] Call Trace:
<4> [110.025891]  dump_stack+0x71/0x9b
<4> [110.025907]  mark_lock+0x49a/0x500
<4> [110.025926]  ? print_shortest_lock_dependencies+0x200/0x200
<4> [110.025946]  mark_held_locks+0x49/0x70
<4> [110.025962]  ? _raw_spin_unlock_irq+0x24/0x50
<4> [110.025978]  lockdep_hardirqs_on+0xa2/0x1c0
<4> [110.025995]  _raw_spin_unlock_irq+0x24/0x50
<4> [110.026171]  virtual_context_destroy+0xc5/0x2e0 [i915]
<4> [110.026376]  __active_retire+0xb4/0x290 [i915]
<4> [110.026396]  dma_fence_signal_locked+0x9e/0x1b0
<4> [110.026613]  i915_request_retire+0x451/0x930 [i915]
<4> [110.026766]  retire_requests+0x4d/0x60 [i915]
<4> [110.026919]  engine_retire+0x63/0xe0 [i915]

Fixes: b1e3177bd1 ("drm/i915: Coordinate i915_active with its own mutex")
Fixes: 6d06779e86 ("drm/i915: Load balancing across a virtual engine")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191205145934.663183-1-chris@chris-wilson.co.uk
2019-12-05 17:27:55 +00:00
Chris Wilson
f70de8d2ca drm/i915/gt: Track the context validity explicitly
Rather than assume if and only if the engine->default_state is not set
that the context is invalid, instead track when we know the context has
valid state -- either because we have copied the default_state or we
have completed a context switch to save the HW state.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191203124155.3019926-1-chris@chris-wilson.co.uk
2019-12-03 16:49:31 +00:00
Chris Wilson
49e74c8f9a drm/i915/execlists: Skip nested spinlock for validating pending
Only along the submission path can we guarantee that the locked request
is indeed from a foreign engine, and so the nesting of engine/rq is
permissible. On the submission tasklet (process_csb()), we may find
ourselves competing with the normal nesting of rq/engine, invalidating
our nesting. As we only use the spinlock for debug purposes, skip the
debug if we cannot acquire the spinlock for safe validation - catching
99% of the bugs is better than causing a hard lockup.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Fixes: c95d31c3df ("drm/i915/execlists: Lock the request while validating it during promotion")
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191203152631.3107653-2-chris@chris-wilson.co.uk
2019-12-03 15:42:28 +00:00
Chris Wilson
80aac91b27 drm/i915/execlists: Add a couple more validity checks to assert_pending()
Check the pending request submission is valid: that it at least has a
reference for the submission and that the request is on the active list.

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/20191203152631.3107653-1-chris@chris-wilson.co.uk
2019-12-03 15:42:28 +00:00
Chris Wilson
97c1635397 drm/i915/execlists: Ensure the tasklet is decoupled upon shutdown
As we only cancel the timers asynchronously, they may
still be running on another CPU as we shutdown, raising one last
softirq. So be safe and make sure the tasklet is flushed before
destroying the engine's memory.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191129172542.1222810-1-chris@chris-wilson.co.uk
2019-11-29 20:09:14 +00:00
Chris Wilson
311770173f drm/i915/gt: Schedule request retirement when timeline idles
The major drawback of commit 7e34f4e4aa ("drm/i915/gen8+: Add RC6 CTX
corruption WA") is that it disables RC6 while Skylake (and friends) is
active, and we do not consider the GPU idle until all outstanding
requests have been retired and the engine switched over to the kernel
context. If userspace is idle, this task falls onto our background idle
worker, which only runs roughly once a second, meaning that userspace has
to have been idle for a couple of seconds before we enable RC6 again.
Naturally, this causes us to consume considerably more energy than
before as powersaving is effectively disabled while a display server
(here's looking at you Xorg) is running.

As execlists will get a completion event as each context is completed,
we can use this interrupt to queue a retire worker bound to this engine
to cleanup idle timelines. We will then immediately notice the idle
engine (without userspace intervention or the aid of the background
retire worker) and start parking the GPU. Thus during light workloads,
we will do much more work to idle the GPU faster...  Hopefully with
commensurate power saving!

v2: Watch context completions and only look at those local to the engine
when retiring to reduce the amount of excess work we perform.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=112315
References: 7e34f4e4aa ("drm/i915/gen8+: Add RC6 CTX corruption WA")
References: 2248a28384 ("drm/i915/gen8+: Add RC6 CTX corruption WA")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191125105858.1718307-3-chris@chris-wilson.co.uk
(cherry picked from commit 4f88f8747f)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
2019-11-25 16:39:07 +02:00
Chris Wilson
4ec5cc78c1 drm/i915/execlists: Fixup cancel_port_requests()
I rushed a last minute correction to cancel_port_requests() to prevent
the snooping of *execlists->active as the inflight array was being
updated, without noticing we iterated the inflight array starting from
active! Oops.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=112387
Fixes: 97f9af78f3 ("drm/i915/gt: Mark the execlists->active as the primary volatile access")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191125112520.1760492-1-chris@chris-wilson.co.uk
(cherry picked from commit da0ef77e1e)
[Joonas: Fixed Fixes: tag to match drm-intel-next-fixes]
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
2019-11-25 16:38:51 +02:00
Chris Wilson
97f9af78f3 drm/i915/gt: Mark the execlists->active as the primary volatile access
Since we want to do a lockless read of the current active request, and
that request is written to by process_csb also without serialisation, we
need to instruct gcc to take care in reading the pointer itself.

Otherwise, we have observed execlists_active() to report 0x40.

[ 2400.760381] igt/para-4098    1..s. 2376479300us : process_csb: rcs0 cs-irq head=3, tail=4
[ 2400.760826] igt/para-4098    1..s. 2376479303us : process_csb: rcs0 csb[4]: status=0x00000001:0x00000000
[ 2400.761271] igt/para-4098    1..s. 2376479306us : trace_ports: rcs0: promote { b9c59:2622, b9c55:2624 }
[ 2400.761726] igt/para-4097    0d... 2376479311us : __i915_schedule: rcs0: -2147483648->3, inflight:0000000000000040, rq:ffff888208c1e940

which is impossible!

The answer is that as we keep the existing execlists->active pointing
into the array as we copy over that array, the unserialised read may see
a partial pointer value.

Fixes: df40306902 ("drm/i915/execlists: Lift process_csb() out of the irq-off spinlock")
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/20191125094318.1630806-1-chris@chris-wilson.co.uk
(cherry picked from commit 331bf90591)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
2019-11-25 16:36:40 +02:00
Chris Wilson
ee33baa831 drm/i915: Mark up the calling context for intel_wakeref_put()
Previously, we assumed we could use mutex_trylock() within an atomic
context, falling back to a worker if contended. However, such trickery
is illegal inside interrupt context, and so we need to always use a
worker under such circumstances. As we normally are in process context,
we can typically use a plain mutex, and only defer to a work when we
know we are being called from an interrupt path.

Fixes: 51fbd8de87 ("drm/i915/pmu: Atomically acquire the gt_pm wakeref")
References: a0855d24fc ("locking/mutex: Complain upon mutex API misuse in IRQ contexts")
References: https://bugs.freedesktop.org/show_bug.cgi?id=111626
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191120125433.3767149-1-chris@chris-wilson.co.uk
(cherry picked from commit 07779a76ee)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
2019-11-25 15:29:17 +02:00
Chris Wilson
4f88f8747f drm/i915/gt: Schedule request retirement when timeline idles
The major drawback of commit 7e34f4e4aa ("drm/i915/gen8+: Add RC6 CTX
corruption WA") is that it disables RC6 while Skylake (and friends) is
active, and we do not consider the GPU idle until all outstanding
requests have been retired and the engine switched over to the kernel
context. If userspace is idle, this task falls onto our background idle
worker, which only runs roughly once a second, meaning that userspace has
to have been idle for a couple of seconds before we enable RC6 again.
Naturally, this causes us to consume considerably more energy than
before as powersaving is effectively disabled while a display server
(here's looking at you Xorg) is running.

As execlists will get a completion event as each context is completed,
we can use this interrupt to queue a retire worker bound to this engine
to cleanup idle timelines. We will then immediately notice the idle
engine (without userspace intervention or the aid of the background
retire worker) and start parking the GPU. Thus during light workloads,
we will do much more work to idle the GPU faster...  Hopefully with
commensurate power saving!

v2: Watch context completions and only look at those local to the engine
when retiring to reduce the amount of excess work we perform.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=112315
References: 7e34f4e4aa ("drm/i915/gen8+: Add RC6 CTX corruption WA")
References: 2248a28384 ("drm/i915/gen8+: Add RC6 CTX corruption WA")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191125105858.1718307-3-chris@chris-wilson.co.uk
2019-11-25 13:17:18 +00:00
Chris Wilson
da0ef77e1e drm/i915/execlists: Fixup cancel_port_requests()
I rushed a last minute correction to cancel_port_requests() to prevent
the snooping of *execlists->active as the inflight array was being
updated, without noticing we iterated the inflight array starting from
active! Oops.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=112387
Fixes: 331bf90591 ("drm/i915/gt: Mark the execlists->active as the primary volatile access")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191125112520.1760492-1-chris@chris-wilson.co.uk
2019-11-25 13:17:18 +00:00
Chris Wilson
331bf90591 drm/i915/gt: Mark the execlists->active as the primary volatile access
Since we want to do a lockless read of the current active request, and
that request is written to by process_csb also without serialisation, we
need to instruct gcc to take care in reading the pointer itself.

Otherwise, we have observed execlists_active() to report 0x40.

[ 2400.760381] igt/para-4098    1..s. 2376479300us : process_csb: rcs0 cs-irq head=3, tail=4
[ 2400.760826] igt/para-4098    1..s. 2376479303us : process_csb: rcs0 csb[4]: status=0x00000001:0x00000000
[ 2400.761271] igt/para-4098    1..s. 2376479306us : trace_ports: rcs0: promote { b9c59:2622, b9c55:2624 }
[ 2400.761726] igt/para-4097    0d... 2376479311us : __i915_schedule: rcs0: -2147483648->3, inflight:0000000000000040, rq:ffff888208c1e940

which is impossible!

The answer is that as we keep the existing execlists->active pointing
into the array as we copy over that array, the unserialised read may see
a partial pointer value.

Fixes: df40306902 ("drm/i915/execlists: Lift process_csb() out of the irq-off spinlock")
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/20191125094318.1630806-1-chris@chris-wilson.co.uk
2019-11-25 09:45:37 +00:00
Chris Wilson
93b0e8fe47 drm/i915: Mark intel_wakeref_get() as a sleeper
Assume that intel_wakeref_get() may take the mutex, and perform other
sleeping actions in the course of its callbacks and so use might_sleep()
to ensure that all callers abide. Anything that cannot sleep has to use
e.g. intel_wakeref_get_if_active() to guarantee its avoidance of the
non-atomic paths.

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/20191121130528.309474-1-chris@chris-wilson.co.uk
2019-11-21 13:22:04 +00:00
Chris Wilson
c95d31c3df drm/i915/execlists: Lock the request while validating it during promotion
Since the request is already on the HW as we perform its validation, it
and even its subsequent barrier may be concurrently retired before we
process the assertions. If it is retired already and so off the HW, our
assertions become void and we need to ignore them.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=112363
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191121103546.146487-1-chris@chris-wilson.co.uk
2019-11-21 12:14:45 +00:00
Chris Wilson
07779a76ee drm/i915: Mark up the calling context for intel_wakeref_put()
Previously, we assumed we could use mutex_trylock() within an atomic
context, falling back to a worker if contended. However, such trickery
is illegal inside interrupt context, and so we need to always use a
worker under such circumstances. As we normally are in process context,
we can typically use a plain mutex, and only defer to a work when we
know we are being called from an interrupt path.

Fixes: 51fbd8de87 ("drm/i915/pmu: Atomically acquire the gt_pm wakeref")
References: a0855d24fc ("locking/mutex: Complain upon mutex API misuse in IRQ contexts")
References: https://bugs.freedesktop.org/show_bug.cgi?id=111626
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191120125433.3767149-1-chris@chris-wilson.co.uk
2019-11-20 15:59:23 +00:00
Chris Wilson
98ae6fb3f1 drm/i915/execlists: Move reset_active() from schedule-out to schedule-in
The gem_ctx_persistence/smoketest was detecting an odd coherency issue
inside the LRC context image; that the address of the ring buffer did
not match our associated struct intel_ring. As we set the address into
the context image when we pin the ring buffer into place before the
context is active, that leaves the question of where did it get
overwritten. Either the HW context save occurred after our pin which
would imply that our idle barriers are broken, or we overwrote the
context image ourselves. It is only in reset_active() where we dabble
inside the context image outside of a serialised path from schedule-out;
but we could equally perform the operation inside schedule-in which is
then fully serialised with the context pin -- and remains serialised by
the engine pulse with kill_context(). (The only downside, aside from
doing more work inside the engine->active.lock, was the plan to merge
all the reset paths into doing their context scrubbing on schedule-out
needs more thought.)

Fixes: d12acee84f ("drm/i915/execlists: Cancel banned contexts on schedule-out")
Testcase: igt/gem_ctx_persistence/smoketest
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191111133205.11590-3-chris@chris-wilson.co.uk
(cherry picked from commit 31b61f0ef9)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
2019-11-13 12:26:35 +02:00
Chris Wilson
31b61f0ef9 drm/i915/execlists: Move reset_active() from schedule-out to schedule-in
The gem_ctx_persistence/smoketest was detecting an odd coherency issue
inside the LRC context image; that the address of the ring buffer did
not match our associated struct intel_ring. As we set the address into
the context image when we pin the ring buffer into place before the
context is active, that leaves the question of where did it get
overwritten. Either the HW context save occurred after our pin which
would imply that our idle barriers are broken, or we overwrote the
context image ourselves. It is only in reset_active() where we dabble
inside the context image outside of a serialised path from schedule-out;
but we could equally perform the operation inside schedule-in which is
then fully serialised with the context pin -- and remains serialised by
the engine pulse with kill_context(). (The only downside, aside from
doing more work inside the engine->active.lock, was the plan to merge
all the reset paths into doing their context scrubbing on schedule-out
needs more thought.)

Fixes: d12acee84f ("drm/i915/execlists: Cancel banned contexts on schedule-out")
Testcase: igt/gem_ctx_persistence/smoketest
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191111133205.11590-3-chris@chris-wilson.co.uk
2019-11-11 16:37:05 +00:00
Chris Wilson
69a48c1d28 drm/i915/execlists: Reduce barrier on context switch to a wmb()
Having been forced to reduce Braswell back to using the aliasing ppgtt,
the coherency issue we previously observed cannot impact us. Reduce the
performance penalty imposed on all platforms from using the mfence to a
mere sfence.

References: cf66b8a0ba ("drm/i915/execlists: Apply a full mb before execution for Braswell")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191110185806.17413-10-chris@chris-wilson.co.uk
2019-11-11 13:27:03 +00:00
Chris Wilson
0a1f57b86c drm/i915/execlists: Reset CSB pointers by mmio as well
Sometimes Icelake forgets to reset the CSB pointers on a GPU reset,
leading to it carry on updating the old tail of the buffer.

<0>[  618.138490] i915_sel-5636    3d..1 673425465us : trace_ports: vecs0: submit { 14de2:504, 0:0 }
<0>[  618.138490] i915_sel-5636    3.... 673425493us : intel_engine_reset: vecs0 flags=100
<0>[  618.138490] i915_sel-5636    3.... 673425493us : execlists_reset_prepare: vecs0: depth<-0
<0>[  618.138490] i915_sel-5636    3.... 673425493us : intel_engine_stop_cs: vecs0
<0>[  618.138490] i915_sel-5636    3.... 673425523us : __intel_gt_reset: engine_mask=40
<0>[  618.138490] i915_sel-5636    3.... 673425568us : execlists_reset: vecs0
<0>[  618.138490] i915_sel-5636    3d..1 673425568us : process_csb: vecs0 cs-irq head=1, tail=2
<0>[  618.138490] i915_sel-5636    3d..1 673425568us : process_csb: vecs0 csb[2]: status=0x00000001:0x40000000
<0>[  618.138490] i915_sel-5636    3d..1 673425569us : trace_ports: vecs0: promote { 14de2:504*, 0:0 }
<0>[  618.138490] i915_sel-5636    3d..1 673425570us : __i915_request_reset: vecs0 rq=14de2:504, guilty? yes
<0>[  618.138490] i915_sel-5636    3d..1 673425571us : __execlists_reset: vecs0 replay {head:2de0, tail:2e48}
<0>[  618.138490] i915_sel-5636    3d..1 673425572us : __i915_request_unsubmit: vecs0 fence 14de2:504, current 503
<0>[  618.138490] i915_sel-5636    3.... 673435544us : intel_engine_cancel_stop_cs: vecs0
<0>[  618.138490] i915_sel-5636    3.... 673435544us : process_csb: vecs0 cs-irq head=11, tail=11
<0>[  618.138490] i915_sel-5636    3d..1 673435545us : __i915_request_submit: vecs0 fence 14de2:504, current 503
<0>[  618.138490] i915_sel-5636    3d..1 673435546us : __execlists_submission_tasklet: vecs0: queue_priority_hint:-2147483648, submit:yes
<0>[  618.138490] i915_sel-5636    3d..1 673435548us : trace_ports: vecs0: submit { 14de2:504*, 0:0 }
<0>[  618.138490] i915_sel-5636    3.... 673435549us : execlists_reset_finish: vecs0: depth->0
<0>[  618.138490] ksoftirq-21      2..s. 673435592us : process_csb: vecs0 cs-irq head=11, tail=3
<0>[  618.138490] ksoftirq-21      2..s. 673435593us : process_csb: vecs0 csb[0]: status=0x00000001:0x40000000
<0>[  618.138490] ksoftirq-21      2..s. 673435594us : trace_ports: vecs0: promote { 14de2:504*, 0:0 }
<0>[  618.138490] ksoftirq-21      2..s. 673435596us : process_csb: vecs0 csb[1]: status=0x00000018:0x40000040
<0>[  618.138490] ksoftirq-21      2..s. 673435597us : trace_ports: vecs0: completed { 14de2:504*, 0:0 }
<0>[  618.138490] ksoftirq-21      2..s. 673435612us : process_csb: process_csb:2188 GEM_BUG_ON(!i915_request_completed(*execlists->active) && !reset_in_progress(execlists))

After the reset, we do another clflush before checking the CSB to be
sure we see whatever was left in the CSB prior to the reset. So it is
unlikely to be an incoherent view of the CSB, and more likely that
Icelake didn't reset its pointers.

References: 582a6f90aa ("drm/i915/execlists: Add a paranoid flush of the CSB pointers upon reset")
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/20191104135307.21083-1-chris@chris-wilson.co.uk
2019-11-04 15:54:26 +00:00
Chris Wilson
3809875071 drm/i915/execlists: Ignore the inactive kernel context in assert_pending_valid
Filter out warnings for the kernel context that is used to flush
inactive contexts, as they do no not pose a risk.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191101082919.21122-1-chris@chris-wilson.co.uk
2019-11-02 14:48:32 +00:00
Chris Wilson
b0b1024886 drm/i915/execlists: Verify context register state before execution
Check that the context's ring register state still matches our
expectations prior to execution.

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/20191102125739.24626-1-chris@chris-wilson.co.uk
2019-11-02 13:39:13 +00:00
Daniele Ceraolo Spurio
9f37940756 drm/i915: drop lrc header page
Recent GuC binaries (including all the ones we're currently using)
don't require this shared area anymore, having moved the relevant
entries into the stage pool instead. i915 itself doesn't write
anything into it either, so we can safely drop it.

Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20191031013040.25803-1-daniele.ceraolospurio@intel.com
2019-10-31 16:47:22 +00:00
Chris Wilson
b79029b2e8 drm/i915/gt: Make timeslice duration configurable
Execlists uses a scheduling quantum (a timeslice) to alternate execution
between ready-to-run contexts of equal priority. This ensures that all
users (though only if they of equal importance) have the opportunity to
run and prevents livelocks where contexts may have implicit ordering due
to userspace semaphores. However, not all workloads necessarily benefit
from timeslicing and in the extreme some sysadmin may want to disable or
reduce the timeslicing granularity.

The timeslicing mechanism can be compiled out^W^W disabled (but should
DCE!) with

	./scripts/config --set-val DRM_I915_TIMESLICE_DURATION 0

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191029091632.26281-1-chris@chris-wilson.co.uk
2019-10-29 16:23:55 +00:00
Michal Wajdeczko
19c17b763f drm/i915/execlists: Use vfunc to check engine submission mode
While processing CSB there is no need to look at GuC submission
settings, just check if engine is configured for execlists mode.

While today GuC submission is disabled it's settings are still
based on modparam values that might not correctly reflect actual
submission status in case of any fallback. Until that is fully
fixed, use alternate method to confirm that engine really runs in
execlists mode by comparing set_default_submission vfunc.

v2: add other immediate use of new helper

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
Reviewed-by: Janusz Krzysztofik <janusz.krzysztofik@linux.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/20191028164520.31772-1-michal.wajdeczko@intel.com
2019-10-28 20:40:07 +00:00
Chris Wilson
a7f328fc78 drm/i915/execlists: Simply walk back along request timeline on reset
The request's timeline will only contain requests from this context, in
order of execution. Therefore, we can simply look back along this
timeline to find the currently executing request.

If we do find that the current context has completed its last request,
that does not imply that all requests are completed in the context, so
only advance the ring->head up to the end of the known completions!

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191028124125.25176-1-chris@chris-wilson.co.uk
2019-10-28 16:09:44 +00:00
Chris Wilson
35865aef05 drm/i915/tgl: Adjust the location of RING_MI_MODE in the context image
The location of RING_MI_MODE (used to stop the ring across resets) moved
for Tigerlake. Fixup the new location and include a selftest to verify
the location in the default context image.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Acked-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191026082220.32632-1-chris@chris-wilson.co.uk
2019-10-26 09:48:34 +01:00
Tvrtko Ursulin
5932925ac1 drm/i915: Move intel_engine_context_in/out into intel_lrc.c
Intel_lrc.c is the only caller and so to avoid some header file ordering
issues in future patches move these two over there.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20191025090952.10135-1-tvrtko.ursulin@linux.intel.com
2019-10-25 13:22:04 +01:00
Chris Wilson
2871ea85c1 drm/i915/gt: Split intel_ring_submission
Split the legacy submission backend from the common CS ring buffer
handling.

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/20191024100344.5041-1-chris@chris-wilson.co.uk
2019-10-24 12:14:21 +01:00
Chris Wilson
d12acee84f drm/i915/execlists: Cancel banned contexts on schedule-out
On schedule-out (CS completion) of a banned context, scrub the context
image so that we do not replay the active payload. The intent is that we
skip banned payloads on request submission so that the timeline
advancement continues on in the background. However, if we are returning
to a preempted request, i915_request_skip() is ineffective and instead we
need to patch up the context image so that it continues from the start
of the next request.

v2: Fixup cancellation so that we only scrub the payload of the active
request and do not short-circuit the breadcrumbs (which might cause
other contexts to execute out of order).
v3: Grammar pass

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191023133108.21401-3-chris@chris-wilson.co.uk
2019-10-23 23:52:10 +01:00
Chris Wilson
3a7a92aba8 drm/i915/execlists: Force preemption
If the preempted context takes too long to relinquish control, e.g. it
is stuck inside a shader with arbitration disabled, evict that context
with an engine reset. This ensures that preemptions are reasonably
responsive, providing a tighter QoS for the more important context at
the cost of flagging unresponsive contexts more frequently (i.e. instead
of using an ~10s hangcheck, we now evict at ~100ms).  The challenge of
lies in picking a timeout that can be reasonably serviced by HW for
typical workloads, balancing the existing clients against the needs for
responsiveness.

Note that coupled with timeslicing, this will lead to rapid GPU "hang"
detection with multiple active contexts vying for GPU time.

The forced preemption mechanism can be compiled out with

	./scripts/config --set-val DRM_I915_PREEMPT_TIMEOUT 0

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/20191023133108.21401-2-chris@chris-wilson.co.uk
2019-10-23 23:52:10 +01:00
Chris Wilson
0587152bf9 drm/i915: Drop assertion that ce->pin_mutex guards state updates
The actual conditions are that we know the GPU is not accessing the
context, and we hold a pin on the context image to allow CPU access. We
used a fake lock on ce->pin_mutex so that we could try and use lockdep
to assert that access is serialised, but the various different
hardirq/softirq contexts where we need to *fake* holding the pin_mutex
are causing more trouble.

Still it would be nice if we did have a way to reassure ourselves that
the direct update to the context image is serialised with GPU execution.
In the meantime, stop lockdep complaining about false irq inversions.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111923
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191022122845.25038-1-chris@chris-wilson.co.uk
2019-10-22 13:32:01 +01:00
Chris Wilson
253a774bb0 drm/i915/execlists: Don't merely skip submission if maybe timeslicing
Normally, we try and skip submission if ELSP[1] is filled. However, we
may desire to enable timeslicing due to the queue priority, even if
ELSP[1] itself does not require timeslicing. That is the queue is equal
priority to ELSP[0] and higher priority then ELSP[1]. Previously, we
would wait until the context switch to preempt the current ELSP[1], but
with timeslicing, we want to preempt ELSP[0] and replace it with the
queue.

In writing the test case, it become quickly apparent that we were also
suppressing the tasklet during promotion and so failing to notice when
the queue started requiring timeslicing.

Fixes: 2229adc813 ("drm/i915/execlist: Trim immediate timeslice expiry")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191018072027.31948-1-chris@chris-wilson.co.uk
2019-10-18 11:23:26 +01:00
Chris Wilson
2229adc813 drm/i915/execlist: Trim immediate timeslice expiry
We perform timeslicing immediately upon receipt of a request that may be
put into the second ELSP slot. The idea behind this was that since we
didn't install the timer if the second ELSP slot was empty, we would not
have any idea of how long ELSP[0] had been running and so giving the
newcomer a chance on the GPU was fair. However, this causes us extra
busy work that we may be able to avoid if we wait a jiffie for the first
timeslice as normal.

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/20191016100851.4979-1-chris@chris-wilson.co.uk
2019-10-16 14:05:45 +01:00
Mika Kuoppala
08fff7aedd drm/i915/tgl: Wa_1607138340
Avoid possible cs hang with semaphores by disabling
lite restore.

Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.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/20191015154449.10338-11-mika.kuoppala@linux.intel.com
2019-10-15 18:25:52 +01:00
Mika Kuoppala
2e19af9438 drm/i915/tgl: Wa_1409600907
To avoid possible hang, we need to add depth stall if we flush the
depth cache.

Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.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/20191015154449.10338-8-mika.kuoppala@linux.intel.com
2019-10-15 18:23:10 +01:00
Mika Kuoppala
36a6b5d964 drm/i915/tgl: Add extra hdc flush workaround
In order to ensure constant caches are invalidated
properly with a0, we need extra hdc flush after invalidation.

v2: use IS_TGL_REVID (Chris)

References: HSDES#1604544889
Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.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/20191015154449.10338-4-mika.kuoppala@linux.intel.com
2019-10-15 18:16:51 +01:00
Mika Kuoppala
4aa0b5d457 drm/i915/tgl: Add HDC Pipeline Flush
Add hdc pipeline flush to ensure memory state is coherent
in L3 when we are done.

v2: Flush also in breadcrumbs (Chris)

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.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/20191015154449.10338-3-mika.kuoppala@linux.intel.com
2019-10-15 18:15:59 +01:00
Mika Kuoppala
62037ffff2 drm/i915/tgl: Include ro parts of l3 to invalidate
Aim for completeness and invalidate also the ro parts
in l3 cache. This might allow to get rid of the preparser
disable/enable workaround on invalidation path.

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.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/20191015154449.10338-2-mika.kuoppala@linux.intel.com
2019-10-15 18:13:50 +01:00
Chris Wilson
8b390c1581 drm/i915/execlists: Clear semaphore immediately upon ELSP promotion
There is no significance to our delay before clearing the semaphore the
engine is waiting on, so release it as soon as we acknowledge the CS
update following our preemption request. This should allow the GPU to
resume work earlier, if it was stuck on the semaphore at the end of a
request.

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/20191015093204.25693-1-chris@chris-wilson.co.uk
2019-10-15 11:51:13 +01:00
Chris Wilson
3c00660db1 drm/i915/execlists: Assert tasklet is locked for process_csb()
We rely on only the tasklet being allowed to call into process_csb(), so
assert that is locked when we do. As the tasklet uses a simple bitlock,
there is no strong lockdep checking so we must make do with a plain
assertion that the tasklet is running and assume that we are the
tasklet!

v2: Fixup intel_gt_sanitize() to prepare each engine for the reset so
that the locks are marked as held during the reset
v3: Check for existent function pointers for very early sanitisation.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191014121336.30137-1-chris@chris-wilson.co.uk
2019-10-14 21:10:59 +01:00
Chris Wilson
89b6d1831d drm/i915/execlists: Tweak virtual unsubmission
Since commit e2144503bf ("drm/i915: Prevent bonded requests from
overtaking each other on preemption") we have restricted requests to run
on their chosen engine across preemption events. We can take this
restriction into account to know that we will want to resubmit those
requests onto the same physical engine, and so can shortcircuit the
virtual engine selection process and keep the request on the same
engine during unwind.

References: e2144503bf ("drm/i915: Prevent bonded requests from overtaking each other on preemption")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Ramlingam C <ramalingam.c@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191013203012.25208-1-chris@chris-wilson.co.uk
2019-10-14 12:51:17 +01:00
Chris Wilson
c3eb54aad9 drm/i915: Mark up "sentinel" requests
Sometimes we want to emit a terminator request, a request that flushes
the pipeline and allows no request to come after it. This can be used
for a "preempt-to-idle" to ensure that upon processing the
context-switch to that request, all other active contexts have been
flushed.

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/20191012070136.32058-1-chris@chris-wilson.co.uk
2019-10-12 08:51:17 +01:00
Chris Wilson
d8ad5f5261 drm/i915/execlists: Prevent merging requests with conflicting flags
We set out-of-bound parameters inside the i915_requests.flags field,
such as disabling preemption or marking the end-of-context. We should
not coalesce consecutive requests if they have differing instructions
as we only inspect the last active request in a context. Thus if we
allow a later request to be merged into the same execution context, it
will mask any of the earlier flags.

References: 2a98f4e65b ("drm/i915: add infrastructure to hold off preemption on a request")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191011190325.10979-9-chris@chris-wilson.co.uk
2019-10-12 07:54:52 +01:00
Chris Wilson
cbbf278778 drm/i915/execlists: Only mark incomplete requests as -EIO on cancelling
Only the requests that have not completed do we want to change the
status of to signal the -EIO when cancelling the inflight set of requests
upon wedging.

Reported-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191011103345.26013-1-chris@chris-wilson.co.uk
2019-10-11 13:07:24 +01:00
Chris Wilson
c97fb526ca drm/i915/execlists: Leave tell-tales as to why pending[] is bad
Before we BUG out with bad pending state, leave a telltale as to which
test failed.

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: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191010071434.31195-2-chris@chris-wilson.co.uk
2019-10-11 09:43:06 +01:00
Chris Wilson
bd9bec5b6a drm/i915/execlists: Mark up expected state during reset
Move the BUG_ON around slightly and add some explanations for each to
try and capture the expected state more carefully. We want to compare
the expected active state of our bookkeeping as compared to the tracked
HW state.

References: https://bugs.freedesktop.org/show_bug.cgi?id=111937
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/20191010083242.1387-1-chris@chris-wilson.co.uk
2019-10-10 13:52:34 +01:00
Daniele Ceraolo Spurio
9d41318c4e drm/i915/tgl: simplify the lrc register list for !RCS
There are small differences between the blitter and the video engines in
the xcs context image (e.g. registers 0x200 and 0x204 only exist on the
blitter). Since we never explicitly set a value for those register and
given that we don't need to update the offsets in the lrc image when we
change engine within the class for virtual engine because the HW can
handle that, instead of having a separate define for the BCS we can
just restrict the programming to the part we're interested in, which is
common across the engines.

Bspec: 45584
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Stuart Summers <stuart.summers@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/20191009230424.6507-2-daniele.ceraolospurio@intel.com
2019-10-10 10:14:42 +01:00
Daniele Ceraolo Spurio
ba2c74da52 drm/i915/tgl: the BCS engine supports relative MMIO
The specs don't mention any specific HW limitation on the blitter and
manual inspection shows that the HW does set the relative MMIO bit in
the LRI of the blitter context image, so we can remove our limitations.

Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: John Harrison <John.C.Harrison@Intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.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/20191009230424.6507-1-daniele.ceraolospurio@intel.com
2019-10-10 10:12:18 +01:00
Chris Wilson
c949ae4314 drm/i915/execlists: Protect peeking at execlists->active
Now that we dropped the engine->active.lock serialisation from around
process_csb(), direct submission can run concurrently to the interrupt
handler. As such execlists->active may be advanced as we dequeue,
dropping the reference to the request. We need to employ our RCU request
protection to ensure that the request is not freed too early.

Fixes: df40306902 ("drm/i915/execlists: Lift process_csb() out of the irq-off spinlock")
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: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191009100955.21477-1-chris@chris-wilson.co.uk
2019-10-09 19:46:40 +01:00
Chris Wilson
20af04f3dd drm/i915/execlists: Assign virtual_engine->uncore from first sibling
Copy across the engine->uncore shortcut to the virtual_engine from its
first physical engine, similar to the handling of the engine->gt
backpointer.

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/20191008070342.4045-1-chris@chris-wilson.co.uk
2019-10-08 10:14:29 +01:00