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  1. 02 10月, 2018 1 次提交
  3. 07 8月, 2018 1 次提交
    • C
      drm/i915: Interactive RPS mode · 027063b1
      由 Chris Wilson 提交于 
      RPS provides a feedback loop where we use the load during the previous
evaluation interval to decide whether to up or down clock the GPU
frequency. Our responsiveness is split into 3 regimes, a high and low
plateau with the intent to keep the gpu clocked high to cover occasional
stalls under high load, and low despite occasional glitches under steady
low load, and inbetween. However, we run into situations like kodi where
we want to stay at low power (video decoding is done efficiently
inside the fixed function HW and doesn't need high clocks even for high
bitrate streams), but just occasionally the pipeline is more complex
than a video decode and we need a smidgen of extra GPU power to present
on time. In the high power regime, we sample at sub frame intervals with
a bias to upclocking, and conversely at low power we sample over a few
frames worth to provide what we consider to be the right levels of
responsiveness respectively. At low power, we more or less expect to be
kicked out to high power at the start of a busy sequence by waitboosting.

Prior to commit e9af4ea2 ("drm/i915: Avoid waitboosting on the active
request") whenever we missed the frame or stalled, we would immediate go
full throttle and upclock the GPU to max. But in commit e9af4ea2, we
relaxed the waitboosting to only apply if the pipeline was deep to avoid
over-committing resources for a near miss. Sadly though, a near miss is
still a miss, and perceptible as jitter in the frame delivery.

To try and prevent the near miss before having to resort to boosting
after the fact, we use the pageflip queue as an indication that we are
in an "interactive" regime and so should sample the load more frequently
to provide power before the frame misses it vblank. This will make us
more favorable to providing a small power increase (one or two bins) as
required rather than going all the way to maximum and then having to
work back down again. (We still keep the waitboosting mechanism around
just in case a dramatic change in system load requires urgent uplocking,
faster than we can provide in a few evaluation intervals.)

v2: Reduce rps_set_interactive to a boolean parameter to avoid the
confusion of what if they wanted a new power mode after pinning to a
different mode (which to choose?)
v3: Only reprogram RPS while the GT is awake, it will be set when we
wake the GT, and while off warns about being used outside of rpm.
v4: Fix deferred application of interactive mode
v5: s/state/interactive/
v6: Group the mutex with its principle in a substruct

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=107111
Fixes: e9af4ea2 ("drm/i915: Avoid waitboosting on the active request")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Radoslaw Szwichtenberg <radoslaw.szwichtenberg@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180731132629.3381-1-chris@chris-wilson.co.uk
(cherry picked from commit 60548c55)
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
      027063b1
  5. 14 7月, 2018 1 次提交
    • C
      drm/i915/execlists: Drop clear_gtiir() on GPU reset · 60a94324
      由 Chris Wilson 提交于 
      With the new CSB processing code, we are not vulnerable to delayed
delivery of a pre-reset interrupt as we use the CSB status pointers in
the HWSP to decide if we need to parse any CSB events and no longer need
to wait for the first post-reset interrupt to be assured that the CSB
mmio registers are valid.

The new icl code to clear registers has a nasty lock inversion:
[   57.409776] ======================================================
[   57.409779] WARNING: possible circular locking dependency detected
[   57.409783] 4.18.0-rc4-CI-CI_DII_1137+ #1 Tainted: G     U  W
[   57.409785] ------------------------------------------------------
[   57.409788] swapper/6/0 is trying to acquire lock:
[   57.409790] 000000004f304ee5 (&engine->timeline.lock/1){-.-.}, at: execlists_submit_request+0x2b/0x1a0 [i915]
[   57.409841]
               but task is already holding lock:
[   57.409844] 00000000aad89594 (&(&rq->lock)->rlock#2){-.-.}, at: notify_ring+0x2b2/0x480 [i915]
[   57.409869]
               which lock already depends on the new lock.

[   57.409872]
               the existing dependency chain (in reverse order) is:
[   57.409876]
               -> #2 (&(&rq->lock)->rlock#2){-.-.}:
[   57.409900]        notify_ring+0x2b2/0x480 [i915]
[   57.409922]        gen8_cs_irq_handler+0x39/0xa0 [i915]
[   57.409943]        gen11_irq_handler+0x2f0/0x420 [i915]
[   57.409949]        __handle_irq_event_percpu+0x42/0x370
[   57.409952]        handle_irq_event_percpu+0x2b/0x70
[   57.409956]        handle_irq_event+0x2f/0x50
[   57.409959]        handle_edge_irq+0xe7/0x190
[   57.409964]        handle_irq+0x67/0x160
[   57.409967]        do_IRQ+0x5e/0x120
[   57.409971]        ret_from_intr+0x0/0x1d
[   57.409974]        _raw_spin_unlock_irqrestore+0x4e/0x60
[   57.409979]        tasklet_action_common.isra.5+0x47/0xb0
[   57.409982]        __do_softirq+0xd9/0x505
[   57.409985]        irq_exit+0xa9/0xc0
[   57.409988]        do_IRQ+0x9a/0x120
[   57.409991]        ret_from_intr+0x0/0x1d
[   57.409995]        cpuidle_enter_state+0xac/0x360
[   57.409999]        do_idle+0x1f3/0x250
[   57.410004]        cpu_startup_entry+0x6a/0x70
[   57.410010]        start_secondary+0x19d/0x1f0
[   57.410015]        secondary_startup_64+0xa5/0xb0
[   57.410018]
               -> #1 (&(&dev_priv->irq_lock)->rlock){-.-.}:
[   57.410081]        clear_gtiir+0x30/0x200 [i915]
[   57.410116]        execlists_reset+0x6e/0x2b0 [i915]
[   57.410140]        i915_reset_engine+0x111/0x190 [i915]
[   57.410165]        i915_handle_error+0x11a/0x4a0 [i915]
[   57.410198]        i915_hangcheck_elapsed+0x378/0x530 [i915]
[   57.410204]        process_one_work+0x248/0x6c0
[   57.410207]        worker_thread+0x37/0x380
[   57.410211]        kthread+0x119/0x130
[   57.410215]        ret_from_fork+0x3a/0x50
[   57.410217]
               -> #0 (&engine->timeline.lock/1){-.-.}:
[   57.410224]        _raw_spin_lock_irqsave+0x33/0x50
[   57.410256]        execlists_submit_request+0x2b/0x1a0 [i915]
[   57.410289]        submit_notify+0x8d/0x124 [i915]
[   57.410314]        __i915_sw_fence_complete+0x81/0x250 [i915]
[   57.410339]        dma_i915_sw_fence_wake+0xd/0x20 [i915]
[   57.410344]        dma_fence_signal_locked+0x79/0x200
[   57.410368]        notify_ring+0x2ba/0x480 [i915]
[   57.410392]        gen8_cs_irq_handler+0x39/0xa0 [i915]
[   57.410416]        gen11_irq_handler+0x2f0/0x420 [i915]
[   57.410421]        __handle_irq_event_percpu+0x42/0x370
[   57.410425]        handle_irq_event_percpu+0x2b/0x70
[   57.410428]        handle_irq_event+0x2f/0x50
[   57.410432]        handle_edge_irq+0xe7/0x190
[   57.410436]        handle_irq+0x67/0x160
[   57.410439]        do_IRQ+0x5e/0x120
[   57.410445]        ret_from_intr+0x0/0x1d
[   57.410449]        cpuidle_enter_state+0xac/0x360
[   57.410453]        do_idle+0x1f3/0x250
[   57.410456]        cpu_startup_entry+0x6a/0x70
[   57.410460]        start_secondary+0x19d/0x1f0
[   57.410464]        secondary_startup_64+0xa5/0xb0
[   57.410466]
               other info that might help us debug this:

[   57.410471] Chain exists of:
                 &engine->timeline.lock/1 --> &(&dev_priv->irq_lock)->rlock --> &(&rq->lock)->rlock#2

[   57.410481]  Possible unsafe locking scenario:

[   57.410485]        CPU0                    CPU1
[   57.410487]        ----                    ----
[   57.410490]   lock(&(&rq->lock)->rlock#2);
[   57.410494]                                lock(&(&dev_priv->irq_lock)->rlock);
[   57.410498]                                lock(&(&rq->lock)->rlock#2);
[   57.410503]   lock(&engine->timeline.lock/1);
[   57.410506]
                *** DEADLOCK ***

[   57.410511] 4 locks held by swapper/6/0:
[   57.410514]  #0: 0000000074575789 (&(&dev_priv->irq_lock)->rlock){-.-.}, at: gen11_irq_handler+0x8a/0x420 [i915]
[   57.410542]  #1: 000000009b29b30e (rcu_read_lock){....}, at: notify_ring+0x1a/0x480 [i915]
[   57.410573]  #2: 00000000aad89594 (&(&rq->lock)->rlock#2){-.-.}, at: notify_ring+0x2b2/0x480 [i915]
[   57.410601]  #3: 000000009b29b30e (rcu_read_lock){....}, at: submit_notify+0x35/0x124 [i915]
[   57.410635]
               stack backtrace:
[   57.410640] CPU: 6 PID: 0 Comm: swapper/6 Tainted: G     U  W         4.18.0-rc4-CI-CI_DII_1137+ #1
[   57.410644] Hardware name: Intel Corporation Ice Lake Client Platform/IceLake U DDR4 SODIMM PD RVP, BIOS ICLSFWR1.R00.2222.A01.1805300339 05/30/2018
[   57.410650] Call Trace:
[   57.410652]  <IRQ>
[   57.410657]  dump_stack+0x67/0x9b
[   57.410662]  print_circular_bug.isra.16+0x1c8/0x2b0
[   57.410666]  __lock_acquire+0x1897/0x1b50
[   57.410671]  ? lock_acquire+0xa6/0x210
[   57.410674]  lock_acquire+0xa6/0x210
[   57.410706]  ? execlists_submit_request+0x2b/0x1a0 [i915]
[   57.410711]  _raw_spin_lock_irqsave+0x33/0x50
[   57.410741]  ? execlists_submit_request+0x2b/0x1a0 [i915]
[   57.410769]  execlists_submit_request+0x2b/0x1a0 [i915]
[   57.410774]  ? _raw_spin_unlock_irqrestore+0x39/0x60
[   57.410804]  submit_notify+0x8d/0x124 [i915]
[   57.410828]  __i915_sw_fence_complete+0x81/0x250 [i915]
[   57.410854]  dma_i915_sw_fence_wake+0xd/0x20 [i915]
[   57.410858]  dma_fence_signal_locked+0x79/0x200
[   57.410882]  notify_ring+0x2ba/0x480 [i915]
[   57.410907]  gen8_cs_irq_handler+0x39/0xa0 [i915]
[   57.410933]  gen11_irq_handler+0x2f0/0x420 [i915]
[   57.410938]  __handle_irq_event_percpu+0x42/0x370
[   57.410943]  handle_irq_event_percpu+0x2b/0x70
[   57.410947]  handle_irq_event+0x2f/0x50
[   57.410951]  handle_edge_irq+0xe7/0x190
[   57.410955]  handle_irq+0x67/0x160
[   57.410958]  do_IRQ+0x5e/0x120
[   57.410962]  common_interrupt+0xf/0xf
[   57.410965]  </IRQ>
[   57.410969] RIP: 0010:cpuidle_enter_state+0xac/0x360
[   57.410972] Code: 44 00 00 31 ff e8 84 93 91 ff 45 84 f6 74 12 9c 58 f6 c4 02 0f 85 31 02 00 00 31 ff e8 7d 30 98 ff e8 e8 0e 94 ff fb 4c 29 fb <48> ba cf f7 53 e3 a5 9b c4 20 48 89 d8 48 c1 fb 3f 48 f7 ea b8 ff
[   57.411015] RSP: 0018:ffffc90000133e90 EFLAGS: 00000216 ORIG_RAX: ffffffffffffffdd
[   57.411023] RAX: ffff8804ae748040 RBX: 000000000002a97d RCX: 0000000000000000
[   57.411029] RDX: 0000000000000046 RSI: ffffffff82141263 RDI: ffffffff820f05a7
[   57.411035] RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
[   57.411041] R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff8229f078
[   57.411045] R13: ffff8804ab2adfa8 R14: 0000000000000000 R15: 0000000d5de092e3
[   57.411052]  do_idle+0x1f3/0x250
[   57.411055]  cpu_startup_entry+0x6a/0x70
[   57.411059]  start_secondary+0x19d/0x1f0
[   57.411064]  secondary_startup_64+0xa5/0xb0

The easiest remedy is to remove the defunct code.

Fixes: ff047a87 ("drm/i915/icl: Correctly clear lost ctx-switch interrupts across reset for Gen11")
References: fd8526e5 ("drm/i915/execlists: Trust the CSB")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Michel Thierry <michel.thierry@intel.com>
Cc: Oscar Mateo <oscar.mateo@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: NMichel Thierry <michel.thierry@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180713203529.1973-3-chris@chris-wilson.co.uk
      60a94324
  7. 13 7月, 2018 3 次提交
  9. 10 7月, 2018 1 次提交
  11. 06 7月, 2018 1 次提交
  13. 05 7月, 2018 3 次提交
  15. 29 6月, 2018 7 次提交
  17. 28 6月, 2018 1 次提交
    • A
      drm/i915/icp: Add Interrupt Support · 31604222
      由 Anusha Srivatsa 提交于 
      This patch addresses Interrupts from south display engine (SDE).

ICP has two registers - SHOTPLUG_CTL_DDI and SHOTPLUG_CTL_TC.
Introduce these registers and their intended values.

Introduce icp_irq_handler().

The icp_irq_postinstall() takes care of
enabling all PCH interrupt sources, to unmask
them as needed with SDEIMR, as is done
done by ibx_irq_pre_postinstall() for earlier platforms.
We do not need to explicitly call the ibx_irq_pre_postinstall().

Also, while changing these,
s/CPT/PPT/CPT-CNP comment.

v2:
- remove redundant register defines.(Lucas)
- Change register names to be more consistent with
previous platforms (Lucas)

v3:
-Reorder bit defines to a more appropriate location.
 Change the comments. Confirm in the commit message that
 icp_irq_postinstall() need not go to
 ibx_irq_pre_postinstall() and ibx_irq_postinstall()
 as in earlier platforms. (Paulo)

Cc: Lucas De Marchi <lucas.de.marchi@gmail.com>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Reviewed-by: NLucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NAnusha Srivatsa <anusha.srivatsa@intel.com>
[Paulo: coding style bikesheds and rebases].
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1530046343-30649-1-git-send-email-anusha.srivatsa@intel.com
      31604222
  19. 19 6月, 2018 4 次提交
  21. 15 6月, 2018 1 次提交
  23. 13 6月, 2018 1 次提交
  25. 02 6月, 2018 1 次提交
  27. 25 4月, 2018 1 次提交
  29. 21 4月, 2018 3 次提交
  31. 07 4月, 2018 1 次提交
    • C
      drm/i915: Pass the set of guilty engines to i915_reset() · d0667e9c
      由 Chris Wilson 提交于 
      Currently, we rely on inspecting the hangcheck state from within the
i915_reset() routines to determine which engines were guilty of the
hang. This is problematic for cases where we want to run
i915_handle_error() and call i915_reset() independently of hangcheck.
Instead of relying on the indirect parameter passing, turn it into an
explicit parameter providing the set of stalled engines which then are
treated as guilty until proven innocent.

While we are removing the implicit stalled parameter, also make the
reason into an explicit parameter to i915_reset(). We still need a
back-channel for i915_handle_error() to hand over the task to the locked
waiter, but let's keep that its own channel rather than incriminate
another.

This leaves stalled/seqno as being private to hangcheck, with no more
nefarious snooping by reset, be it whole-device or per-engine. \o/

The only real issue now is that this makes it crystal clear that we
don't actually do any testing of hangcheck per se in
drv_selftest/live_hangcheck, merely of resets!
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Michel Thierry <michel.thierry@intel.com>
Cc: Jeff McGee <jeff.mcgee@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: NMichel Thierry <michel.thierry@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180406220354.18911-2-chris@chris-wilson.co.uk
      d0667e9c
  33. 06 4月, 2018 3 次提交
  35. 23 3月, 2018 1 次提交
  37. 20 3月, 2018 2 次提交
  39. 10 3月, 2018 1 次提交
  41. 09 3月, 2018 2 次提交
    • C
      drm/i915: Push irq_shift from gen8_cs_irq_handler() to caller · 51f6b0f9
      由 Chris Wilson 提交于 
      Originally we were inlining gen8_cs_irq_handler() and so expected the
compiler to constant-fold away the irq_shift (so we had hardcoded it as
opposed to use engine->irq_shift). However, we dropped the inline given
the proliferation of gen8_cs_irq_handler()s. If we pull the shifting
of the iir into the caller, we can shrink the code still further:

add/remove: 0/0 grow/shrink: 0/3 up/down: 0/-34 (-34)
Function                                     old     new   delta
gen8_cs_irq_handler                          123     118      -5
gen8_gt_irq_handler                          261     248     -13
gen11_irq_handler                            722     706     -16

v2: Drop gen11_cs_irq_handler now that it is a simple
stub around gen8_cs_irq_handler (Daniele)

References: 5d3d69d5 ("drm/i915: Stop inlining the execlists IRQ handler")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: NDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180309010808.11921-1-chris@chris-wilson.co.uk
      51f6b0f9
    • M
      drm/i915: Handle pipe CRC around enabling/disabling pipe. · 033b7a23
      由 Maarten Lankhorst 提交于 
      This will get rid of the following error:
[   74.730271] WARNING: CPU: 4 PID: 0 at drivers/gpu/drm/drm_vblank.c:614 drm_calc_vbltimestamp_from_scanoutpos+0x13e/0x2f0
[   74.730311] Modules linked in: vgem snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic i915 x86_pkg_temp_thermal intel_powerclamp coretemp snd_hda_intel crct10dif_pclmul snd_hda_codec crc32_pclmul snd_hwdep broadcom ghash_clmulni_intel snd_hda_core bcm_phy_lib snd_pcm tg3 lpc_ich mei_me mei prime_numbers
[   74.730353] CPU: 4 PID: 0 Comm: swapper/4 Tainted: G     U           4.16.0-rc2-CI-CI_DRM_3822+ #1
[   74.730355] Hardware name: Dell Inc. XPS 8300  /0Y2MRG, BIOS A06 10/17/2011
[   74.730359] RIP: 0010:drm_calc_vbltimestamp_from_scanoutpos+0x13e/0x2f0
[   74.730361] RSP: 0018:ffff88022fb03d10 EFLAGS: 00010086
[   74.730365] RAX: ffffffffa0291d20 RBX: ffff88021a180000 RCX: 0000000000000001
[   74.730367] RDX: ffffffff820e7db8 RSI: 0000000000000001 RDI: ffffffff82068cea
[   74.730369] RBP: ffff88022fb03d70 R08: 0000000000000000 R09: ffffffff815d26d0
[   74.730371] R10: 0000000000000000 R11: ffffffffa0161ca0 R12: 0000000000000001
[   74.730373] R13: ffff880212448008 R14: ffff880212448330 R15: 0000000000000000
[   74.730376] FS:  0000000000000000(0000) GS:ffff88022fb00000(0000) knlGS:0000000000000000
[   74.730378] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   74.730380] CR2: 000055edcbec9000 CR3: 0000000002210001 CR4: 00000000000606e0
[   74.730382] Call Trace:
[   74.730385]  <IRQ>
[   74.730397]  drm_get_last_vbltimestamp+0x36/0x50
[   74.730401]  drm_update_vblank_count+0x64/0x240
[   74.730409]  drm_crtc_accurate_vblank_count+0x41/0x90
[   74.730453]  display_pipe_crc_irq_handler+0x176/0x220 [i915]
[   74.730497]  i9xx_pipe_crc_irq_handler+0xfe/0x150 [i915]
[   74.730537]  ironlake_irq_handler+0x618/0xa30 [i915]
[   74.730548]  __handle_irq_event_percpu+0x3c/0x340
[   74.730556]  handle_irq_event_percpu+0x1b/0x50
[   74.730561]  handle_irq_event+0x2f/0x50
[   74.730566]  handle_edge_irq+0xe4/0x1b0
[   74.730572]  handle_irq+0x11/0x20
[   74.730576]  do_IRQ+0x5e/0x120
[   74.730584]  common_interrupt+0x84/0x84
[   74.730586]  </IRQ>
[   74.730591] RIP: 0010:cpuidle_enter_state+0xaa/0x350
[   74.730593] RSP: 0018:ffffc9000008beb8 EFLAGS: 00000212 ORIG_RAX: ffffffffffffffde
[   74.730597] RAX: ffff880226b80040 RBX: 000000000031fc3e RCX: 0000000000000001
[   74.730599] RDX: 0000000000000000 RSI: ffffffff8210fb59 RDI: ffffffff820c02e7
[   74.730601] RBP: 0000000000000004 R08: 00000000000040af R09: 0000000000000018
[   74.730603] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000004
[   74.730606] R13: ffffe8ffffd00430 R14: 0000001166120bf4 R15: ffffffff82294460
[   74.730621]  ? cpuidle_enter_state+0xa6/0x350
[   74.730629]  do_idle+0x188/0x1d0
[   74.730636]  cpu_startup_entry+0x14/0x20
[   74.730641]  start_secondary+0x129/0x160
[   74.730646]  secondary_startup_64+0xa5/0xb0
[   74.730660] Code: e1 48 c7 c2 b8 7d 0e 82 be 01 00 00 00 48 c7 c7 ea 8c 06 82 e8 64 ec ff ff 48 8b 83 c8 07 00 00 48 83 78 28 00 0f 84 e2 fe ff ff <0f> 0b 45 31 ed e9 db fe ff ff 41 b8 d3 4d 62 10 89 c8 6a 03 41
[   74.730754] ---[ end trace 14b1345705b68565 ]---

Changes since v1:
- Don't try to apply CRC workaround when enabling pipe, it should already be enabled.
Changes since v2:
- Make crc functions for !DEBUGFS case inline.
- Pass intel_crtc to crc functions.
- Add comments to callsites.
Changes since v3:
- Cache selected source to pipe_crc->source.
- Set pipe_crc->skipped to MIN_INT during disable to close a race condition.
Changes since v4:
- Handle fallout from setting pipe_crc->source in irq handler.

Cc: Marta Löfstedt <marta.lofstedt@intel.com>
Reported-by: NMarta Löfstedt <marta.lofstedt@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=105185Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180308120202.52446-1-maarten.lankhorst@linux.intel.comReviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
      033b7a23