We have to cleanup after i915_perf_init(), even on the error path, as it
passes a pointer into the module to the sysfs core. If we fail to
unregister the sysctl table, we leave a dangling pointer which then may
explode anytime later.

Fixes: 9f9b2792

 ("drm/i915/perf: reuse timestamp frequency from device info")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180414091233.32224-1-chris@chris-wilson.co.uk

Add a selftest to ensure that we restore the whitelisted registers after
rewrite the registers everytime they might be scrubbed, e.g. module
load, reset and resume. For the other volatile workaround registers, we
export their presence via debugfs and check in igt/gem_workarounds.
However, we don't export the whitelist and rather than do so, let's test
them directly in the kernel.

The test we use is to read the registers back from the CS (this helps us
be sure that the registers will be valid for MI_LRI etc). In order to
generate the expected list, we split intel_whitelist_workarounds_emit
into two phases, the first to build the list and the second to apply.
Inside the test, we only build the list and then check that list against
the hw.

v2: Filter out pre-gen8 as they do not have RING_NONPRIV.
v3: Drop unused engine parameter, no plans to use it now or future.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Oscar Mateo <oscar.mateo@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Oscar Mateo <oscar.mateo@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180414122754.569-1-chris@chris-wilson.co.uk

It looks that GuC does not actively use GUC_CTL_DEVICE_INFO parameter
where we are passing GT type and Core family values.
Let's stop/remove setup of this parameter and remove related
definitions.

v2: (this time without squashed HAX)
  - New title and description
  - Remove also GUC_CORE_FAMILY_* definitions (Michel)
v3:
  - The removed define GUC_CTL_DEVICE_INFO has been restored (Michel)
  - Updated description (Sagar)
v4: rebase

Signed-off-by: Piotr Piórkowski <piotr.piorkowski@intel.com>
Cc: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Cc: Michał Winiarski <michal.winiarski@intel.com>
Cc: John A Spotswood <john.a.spotswood@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michel Thierry <michel.thierry@intel.com>
Acked-by: Michel Thierry <michel.thierry@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/20180413085245.57206-1-piotr.piorkowski@intel.com

Signed-off-by: Jani Nikula <jani.nikula@intel.com>

Evidence indicates that Cannonlake HWSP is not coherent
as it should. Revert to using mmio access for now.

Testcase: igt/gem_ctx_switch
References: https://bugs.freedesktop.org/show_bug.cgi?id=105888


Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Rafael Antognolli <rafael.antognolli@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20180412145802.23313-1-mika.kuoppala@linux.intel.com

No functional changes.

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180411131519.9091-2-jani.nikula@intel.com

The VBT contains the DDC pin to use for specific ports. Alas, sometimes
the field appears to contain bogus data, and while we check for it later
on in intel_gmbus_get_adapter() we fail to check the returned NULL on
errors. Oops results.

The simplest approach seems to be to catch and ignore the bogus DDC pins
already at the VBT parsing phase, reverting to fixed per port default
pins. This doesn't guarantee display working, but at least it prevents
the oops. And we continue to be fuzzed by VBT.

One affected machine is Dell Latitude 5590 where a BIOS upgrade added
invalid DDC pins.

Typical backtrace:

[   35.461411] WARN_ON(!intel_gmbus_is_valid_pin(dev_priv, pin))
[   35.461432] WARNING: CPU: 6 PID: 411 at drivers/gpu/drm/i915/intel_i2c.c:844 intel_gmbus_get_adapter+0x32/0x37 [i915]
[   35.461437] Modules linked in: i915 ahci libahci dm_snapshot dm_bufio dm_raid raid456 async_raid6_recov async_pq raid6_pq async_xor xor async_memcpy async_tx
[   35.461445] CPU: 6 PID: 411 Comm: kworker/u16:2 Not tainted 4.16.0-rc7.x64-g1cda370ffded #1
[   35.461447] Hardware name: Dell Inc. Latitude 5590/0MM81M, BIOS 1.1.9 03/13/2018
[   35.461450] Workqueue: events_unbound async_run_entry_fn
[   35.461465] RIP: 0010:intel_gmbus_get_adapter+0x32/0x37 [i915]
[   35.461467] RSP: 0018:ffff9b4e43d47c40 EFLAGS: 00010286
[   35.461469] RAX: 0000000000000000 RBX: ffff98f90639f800 RCX: ffffffffae051960
[   35.461471] RDX: 0000000000000001 RSI: 0000000000000092 RDI: 0000000000000246
[   35.461472] RBP: ffff98f905410000 R08: 0000004d062a83f6 R09: 00000000000003bd
[   35.461474] R10: 0000000000000031 R11: ffffffffad4eda58 R12: ffff98f905410000
[   35.461475] R13: ffff98f9064c1000 R14: ffff9b4e43d47cf0 R15: ffff98f905410000
[   35.461477] FS:  0000000000000000(0000) GS:ffff98f92e580000(0000) knlGS:0000000000000000
[   35.461479] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   35.461481] CR2: 00007f5682359008 CR3: 00000001b700c005 CR4: 00000000003606e0
[   35.461483] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   35.461484] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   35.461486] Call Trace:
[   35.461501]  intel_hdmi_set_edid+0x37/0x27f [i915]
[   35.461515]  intel_hdmi_detect+0x7c/0x97 [i915]
[   35.461518]  drm_helper_probe_single_connector_modes+0xe1/0x6c0
[   35.461521]  drm_setup_crtcs+0x129/0xa6a
[   35.461523]  ? __switch_to_asm+0x34/0x70
[   35.461525]  ? __switch_to_asm+0x34/0x70
[   35.461527]  ? __switch_to_asm+0x40/0x70
[   35.461528]  ? __switch_to_asm+0x34/0x70
[   35.461529]  ? __switch_to_asm+0x40/0x70
[   35.461531]  ? __switch_to_asm+0x34/0x70
[   35.461532]  ? __switch_to_asm+0x40/0x70
[   35.461534]  ? __switch_to_asm+0x34/0x70
[   35.461536]  __drm_fb_helper_initial_config_and_unlock+0x34/0x46f
[   35.461538]  ? __switch_to_asm+0x40/0x70
[   35.461541]  ? _cond_resched+0x10/0x33
[   35.461557]  intel_fbdev_initial_config+0xf/0x1c [i915]
[   35.461560]  async_run_entry_fn+0x2e/0xf5
[   35.461563]  process_one_work+0x15b/0x364
[   35.461565]  worker_thread+0x2c/0x3a0
[   35.461567]  ? process_one_work+0x364/0x364
[   35.461568]  kthread+0x10c/0x122
[   35.461570]  ? _kthread_create_on_node+0x5d/0x5d
[   35.461572]  ret_from_fork+0x35/0x40
[   35.461574] Code: 74 16 89 f6 48 8d 04 b6 48 c1 e0 05 48 29 f0 48 8d 84 c7 e8 11 00 00 c3 48 c7 c6 b0 19 1e c0 48 c7 c7 64 8a 1c c0 e8 47 88 ed ec <0f> 0b 31 c0 c3 8b 87 a4 04 00 00 80 e4 fc 09 c6 89 b7 a4 04 00
[   35.461604] WARNING: CPU: 6 PID: 411 at drivers/gpu/drm/i915/intel_i2c.c:844 intel_gmbus_get_adapter+0x32/0x37 [i915]
[   35.461606] ---[ end trace 4fe1e63e2dd93373 ]---
[   35.461609] BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
[   35.461613] IP: i2c_transfer+0x4/0x86
[   35.461614] PGD 0 P4D 0
[   35.461616] Oops: 0000 [#1] SMP PTI
[   35.461618] Modules linked in: i915 ahci libahci dm_snapshot dm_bufio dm_raid raid456 async_raid6_recov async_pq raid6_pq async_xor xor async_memcpy async_tx
[   35.461624] CPU: 6 PID: 411 Comm: kworker/u16:2 Tainted: G        W        4.16.0-rc7.x64-g1cda370ffded #1
[   35.461625] Hardware name: Dell Inc. Latitude 5590/0MM81M, BIOS 1.1.9 03/13/2018
[   35.461628] Workqueue: events_unbound async_run_entry_fn
[   35.461630] RIP: 0010:i2c_transfer+0x4/0x86
[   35.461631] RSP: 0018:ffff9b4e43d47b30 EFLAGS: 00010246
[   35.461633] RAX: ffff9b4e43d47b6e RBX: 0000000000000005 RCX: 0000000000000001
[   35.461635] RDX: 0000000000000002 RSI: ffff9b4e43d47b80 RDI: 0000000000000000
[   35.461636] RBP: ffff9b4e43d47bd8 R08: 0000004d062a83f6 R09: 00000000000003bd
[   35.461638] R10: 0000000000000031 R11: ffffffffad4eda58 R12: 0000000000000002
[   35.461639] R13: 0000000000000001 R14: ffff9b4e43d47b6f R15: ffff9b4e43d47c07
[   35.461641] FS:  0000000000000000(0000) GS:ffff98f92e580000(0000) knlGS:0000000000000000
[   35.461643] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   35.461645] CR2: 0000000000000010 CR3: 00000001b700c005 CR4: 00000000003606e0
[   35.461646] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   35.461647] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   35.461649] Call Trace:
[   35.461652]  drm_do_probe_ddc_edid+0xb3/0x128
[   35.461654]  drm_get_edid+0xe5/0x38d
[   35.461669]  intel_hdmi_set_edid+0x45/0x27f [i915]
[   35.461684]  intel_hdmi_detect+0x7c/0x97 [i915]
[   35.461687]  drm_helper_probe_single_connector_modes+0xe1/0x6c0
[   35.461689]  drm_setup_crtcs+0x129/0xa6a
[   35.461691]  ? __switch_to_asm+0x34/0x70
[   35.461693]  ? __switch_to_asm+0x34/0x70
[   35.461694]  ? __switch_to_asm+0x40/0x70
[   35.461696]  ? __switch_to_asm+0x34/0x70
[   35.461697]  ? __switch_to_asm+0x40/0x70
[   35.461698]  ? __switch_to_asm+0x34/0x70
[   35.461700]  ? __switch_to_asm+0x40/0x70
[   35.461701]  ? __switch_to_asm+0x34/0x70
[   35.461703]  __drm_fb_helper_initial_config_and_unlock+0x34/0x46f
[   35.461705]  ? __switch_to_asm+0x40/0x70
[   35.461707]  ? _cond_resched+0x10/0x33
[   35.461724]  intel_fbdev_initial_config+0xf/0x1c [i915]
[   35.461727]  async_run_entry_fn+0x2e/0xf5
[   35.461729]  process_one_work+0x15b/0x364
[   35.461731]  worker_thread+0x2c/0x3a0
[   35.461733]  ? process_one_work+0x364/0x364
[   35.461734]  kthread+0x10c/0x122
[   35.461736]  ? _kthread_create_on_node+0x5d/0x5d
[   35.461738]  ret_from_fork+0x35/0x40
[   35.461739] Code: 5c fa e1 ad 48 89 df e8 ea fb ff ff e9 2a ff ff ff 0f 1f 44 00 00 31 c0 e9 43 fd ff ff 31 c0 45 31 e4 e9 c5 fd ff ff 41 54 55 53 <48> 8b 47 10 48 83 78 10 00 74 70 41 89 d4 48 89 f5 48 89 fb 65
[   35.461756] RIP: i2c_transfer+0x4/0x86 RSP: ffff9b4e43d47b30
[   35.461757] CR2: 0000000000000010
[   35.461759] ---[ end trace 4fe1e63e2dd93374 ]---

Based on a patch by Fei Li.

v2: s/reverting/sticking/ (Chris)

Cc: stable@vger.kernel.org
Cc: Fei Li <fei.li@intel.com>
Co-developed-by: Fei Li <fei.li@intel.com>
Reported-by: Pavel Nakonechnyi <zorg1331@gmail.com>
Reported-and-tested-by: Seweryn Kokot <sewkokot@gmail.com>
Reported-and-tested-by: Laszlo Valko <valko@linux.karinthy.hu>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=105549
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=105961


Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180411131519.9091-1-jani.nikula@intel.com

There are different kind of workarounds (those that modify registers that
live in the context image, those that modify global registers, those that
whitelist registers, etc...) and they have different requirements in terms
of where they are applied and how. Also, by splitting them apart, it should
be easier to decide where a new workaround should go.

v2:
  - Add multiple MISSING_CASE
  - Rebased

v3:
  - Rename mmio_workarounds to gt_workarounds (Chris, Mika)
  - Create empty placeholders for BDW and CHV GT WAs
  - Rebased

v4: Rebased

v5:
 - Rebased
 - FORCE_TO_NONPRIV register exists since BDW, so make a path
   for it to achieve universality, even if empty (Chris)

Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
[ickle: appease checkpatch]
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/1523376767-18480-2-git-send-email-oscar.mateo@intel.com

This has grown to be a sizable amount of code, so move it to
its own file before we try to refactor anything. For the moment,
we are leaving behind the WA BB code and the WAs that get applied
(incorrectly) in init_clock_gating, but we will deal with it later.

v2: Use intel_ prefix for code that deals with the hardware (Chris)
v3: Rebased
v4:
  - Rebased
  - New license header
v5:
  - Rebased
  - Added some organisational notes to the file (Chris)
v6: Include DOC section in the documentation build (Jani)

Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
[ickle: appease checkpatch, mostly]
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/1523376767-18480-1-git-send-email-oscar.mateo@intel.com

We can refine our current execlists->queue_priority if we inspect
ELSP[1] rather than the head of the unsubmitted queue. Currently, we use
the unsubmitted queue and say that if a subsequent request is more
important than the current queue, we will rerun the submission tasklet
to evaluate the need for preemption. However, we only want to preempt if
we need to jump ahead of a currently executing request in ELSP. The
second reason for running the submission tasklet is amalgamate requests
into the active context on ELSP[0] to avoid a stall when ELSP[0] drains.
(Though repeatedly amalgamating requests into the active context and
triggering many lite-restore is off question gain, the goal really is to
put a context into ELSP[1] to cover the interrupt.) So if instead of
looking at the head of the queue, we look at the context in ELSP[1] we
can answer both of the questions more accurately -- we don't need to
rerun the submission tasklet unless our new request is important enough
to feed into, at least, ELSP[1].

v2: Add some comments from the discussion with Tvrtko.
v3: More commentary to cross-reference queue_request()

References: f6322edd

 ("drm/i915/preemption: Allow preemption between submission ports")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michał Winiarski <michal.winiarski@intel.com>
Cc: Michel Thierry <michel.thierry@intel.com>
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/20180411103929.27374-1-chris@chris-wilson.co.uk

Apparently caused by a merge fail at some point. Due to the nature of
the duplicated block, the second one will have no effect, and there's no
need to backport.

Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180410091248.1454-1-jani.nikula@intel.com

While thinking about sporadic failures of perf_pmu/rc6-runtime-pm* tests
on some CI machines I have concluded that: a) the PMU readout of RC6 can
race against runtime PM transitions, and b) there are other reasons than
being runtime suspended which can cause intel_runtime_pm_get_if_in_use to
fail.

Therefore when estimating RC6 the code needs to assert we are indeed in
suspended state, and if not, the best we can do is return the last known
RC6 value.

Without this check we can calculate the estimated value based on un-
initialized or inappropriate internal state, which can result in over-
estimation, or in any case incorrect value being returned.

v2:
 * Re-arrange the code a bit to avoid second unlock and return branch.
   (Chris Wilson)

v3:
 * Insert some strategic blank lines and improve commit msg.
   (Chris Wilson)

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Fixes: 1fe699e3 ("drm/i915/pmu: Fix sleep under atomic in RC6 readout")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=105010


Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Imre Deak <imre.deak@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20180410112704.24462-1-tvrtko.ursulin@linux.intel.com

%phn is not a valid specifier, and the trailing 'n' is being eaten by
the format-specifier and defaulting to the ' ' separator. Avoid angering
smatch by using the unknown specifier, and use the default we expect.

drivers/gpu/drm/i915/intel_guc_ct.c:616 ctb_read() warn: '%ph' cannot be followed by 'n'
drivers/gpu/drm/i915/intel_guc_ct.c:616 ctb_read() warn: '%ph' cannot be followed by 'n'
drivers/gpu/drm/i915/intel_guc_ct.c:616 ctb_read() warn: '%ph' cannot be followed by 'n'
drivers/gpu/drm/i915/intel_guc_ct.c:669 ct_handle_response() warn: '%ph' cannot be followed by 'n'
drivers/gpu/drm/i915/intel_guc_ct.c:679 ct_handle_response() warn: '%ph' cannot be followed by 'n'
drivers/gpu/drm/i915/intel_guc_ct.c:693 ct_handle_response() warn: '%ph' cannot be followed by 'n'
drivers/gpu/drm/i915/intel_guc_ct.c:707 ct_handle_response() warn: '%ph' cannot be followed by 'n'
drivers/gpu/drm/i915/intel_guc_ct.c:727 ct_process_request() warn: '%ph' cannot be followed by 'n'
drivers/gpu/drm/i915/intel_guc_ct.c:803 ct_handle_request() warn: '%ph' cannot be followed by 'n'

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180410111417.27563-1-chris@chris-wilson.co.uk

Resetting the GPU doesn't affect the RPS/RC6 state, so we can stop
forcibly reloading the registers.

Ville suggested this many moons ago, I said at that time that sanitizing
was no harm and meant that our bookkeeping was kept consistent with the
HW. However, in a forthcoming series, we want to split rps/rc6 GT
powermanagement and one of the key simplifications is the control of
when we enable it. Performing a crude sanitize in the middle of
i915_gem_reset() is then a huge wart.

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>
Reviewed-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180410133354.13425-1-chris@chris-wilson.co.uk

Adding a i915_fifo_underrun_reset debugfs file will make it possible
for IGT tests to clear FIFO underrun fallout at the start of each
subtest, and make re-enable FBC so tests always have maximum exposure
to features used by IGT. FIFO underruns and FBC bugs will no longer
hide when an earlier subtests disables both.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
References: https://bugs.freedesktop.org/show_bug.cgi?id=105685
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=105681
Link: https://patchwork.freedesktop.org/patch/msgid/20180328100526.36467-1-maarten.lankhorst@linux.intel.com


Acked-by: Jani Nikula <jani.nikula@linux.intel.com>
[mlankhorst: Reset FBC reason if underrun had occurred. (vivijim)]
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

Inside the psr work function, we want to wait for PSR to idle first and
wish to do so without blocking the normal modeset path, so we do so
without holding the PSR lock. However, we first have to find which pipe
PSR was enabled on, which requires chasing into the PSR struct and
requires locking to prevent intel_psr_disable() from concurrently
setting our pointer to NULL.

Fixes: 995d3047

 ("drm/i915: VLV/CHV PSR Software timer mode")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Durgadoss R <durgadoss.r@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: <stable@vger.kernel.org> # v4.0+
Reviewed-by: Jose Roberto de Souza <jose.souza@intel.com>
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180405114915.29609-1-chris@chris-wilson.co.uk

On GLK sporadic timeouts occur during PHY0 enabling. Based on logs it looks
like they happen sometime after a system suspend/resume cycle, with the
same power well enabling succeeding both before and after the failed
one and no other problems observed. The current timeout in the code is
not actually specified by BSpec, so let's try to increase that until a
BSpec update.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=105771


Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180409122716.4055-1-imre.deak@intel.com


Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

All the references to get_existing_state can be converted to
get_new_state or get_old_state, which means that i915 is now
get_existing_state free.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180409124656.39886-3-maarten.lankhorst@linux.intel.com


[mlankhorst: Fix alignment in prepare_plane_fb. (Ville)]
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

get_existing_crtc_state is currently unused, get rid of it.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180409124656.39886-2-maarten.lankhorst@linux.intel.com


Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

The get_existing macros are deprecated and should be replaced by
get_old/new_state for clarity.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180409124656.39886-1-maarten.lankhorst@linux.intel.com


[mlankhorst: Remove useless warn. (Ville)]
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

Include fence context and seqno in low level tracing so it is easier to
follow flows of individual requests when things go bad.

Also added tracing on the reset side of things.

v2:
 Chris Wilson:
 * Standardize global_seqno and seqno as global.
 * Include current hws seqno in execlists_cancel_port_requests.

v3:
 * Fix port printk format for all builds.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> # v2
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20180406123514.5809-1-tvrtko.ursulin@linux.intel.com

Enclose for_each_engine_masked macro arguments in parentheses.

v2:
 * Fixup whitespace to satisfy checkpatch.
 * Likewise reformat to 80 chars.

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/20180406114407.25360-1-tvrtko.ursulin@linux.intel.com

This patch updates scaler max limit support for NV12

v2: Rebased (me)

v3: Rebased (me)

v4: Missed the Tested-by/Reviewed-by in the previous series
Adding the same to commit message in this version.

v5: Addressed review comments from Ville and rebased
- calculation of max_scale to be made
less convoluted by splitting it up a bit
- Indentation errors to be fixed in the series

v6: Rebased (me)
Fixed review comments from Paauwe, Bob J
Previous version, where a split of calculation
was done, was wrong. Fixed that issue here.

v7: Rebased (me)

v8: Rebased (me)

v9: Rebased (me)

v10: Rebased (me)

v11: Addressed review comments from Shashank Sharma
Alignment issues fixed.
When call to skl_update_scaler is made, 0 was being
sent instead of pixel_format.
When crtc update scaler is called, we dont have the
fb to derive the pixel format. Added the function
parameter bool plane_scaler_check to account for this.

v12: Fixed failure in IGT debugfs_test.
fb is NULL in skl_update_scaler_plane
Due to this, accessing fb->format caused failure.
Patch checks fb before using.

v13: In the previous version there was a flaw.
In skl_update_scaler during plane_scaler_check
if the format was non-NV12, it would set need_scaling
to false. This could reset the previously set need_scaling
from a previous condition check. Patch fixes this.
Patch also adds minimum src height for YUV 420 formats
to 16 (as defined in BSpec) and adds for checking this
range.

v14: Addressed review comments from Maarten
Just add a check for NV12 min src height in
skl_update_scaler and retain the remaining checks
as is. Added Reviewed By from Juha-Pekka Heikkila.

v15: Rebased the series.

v16: Changed fb height restriction to be >= 16 as per
Bspec. Earlier it was > 16.

v17: Adding src width and height to be mult of 4 restriction
to avoid pipe fifo underruns for NV12.

Credits-to: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Tested-by: Clinton Taylor <clinton.a.taylor@intel.com>
Reviewed-by: Clinton Taylor <clinton.a.taylor@intel.com>
Reviewed-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
Signed-off-by: Chandra Konduru <chandra.konduru@intel.com>
Signed-off-by: Nabendu Maiti <nabendu.bikash.maiti@intel.com>
Signed-off-by: Vidya Srinivas <vidya.srinivas@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1523245273-30264-15-git-send-email-vidya.srinivas@intel.com

This patch adds NV12 to format_is_yuv() function
for sprite planes.

v2:
-Use intel_ prefix for format_is_yuv (Ville)

v3: Rebased (me)

v4: Rebased and addressed review comments from Clinton A Taylor.
"static function in intel_sprite.c is not available
to the primary plane functions".
Changed commit message - function modified for
sprite planes.

v5: Missed the Tested-by/Reviewed-by in the previous series
Adding the same to commit message in this version.

v6: Rebased (me)

v7: Rebased (me)

v8: Rebased (me)

v9: Rebased (me)

v10: Changed intel_format_is_yuv function from
static to non-static. We need to use it later from
other files for check.

v11: Rebased the patch. format_is_yuv has already
been renamed to intel_format_is_yuv in the color
patch series which is already merged. This function
which was previously static has already been made
non-static. So this patch after rebase just adds
NV12 to intel_format_is_yuv function.

v12: Added reviewed by from Juha-Pekka Heikkila

v13/v14/v15: Rebased the series

Tested-by: Clinton Taylor <clinton.a.taylor@intel.com>
Reviewed-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
Reviewed-by: Clinton Taylor <clinton.a.taylor@intel.com>
Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
Signed-off-by: Chandra Konduru <chandra.konduru@intel.com>
Signed-off-by: Nabendu Maiti <nabendu.bikash.maiti@intel.com>
Signed-off-by: Vidya Srinivas <vidya.srinivas@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1523245273-30264-14-git-send-email-vidya.srinivas@intel.com

This patch sets appropriate scaler mode for NV12 format.
In this mode, skylake scaler does either chroma-upsampling or
chroma-upsampling and resolution scaling

v2: Review comments from Ville addressed
NV12 case to be checked first for setting
the scaler

v3: Rebased (me)

v4: Rebased (me)

v5: Missed the Tested-by/Reviewed-by in the previous series
Adding the same to commit message in this version.

v6: Rebased (me)

v7: Rebased (me)

v8: Rebased (me)
Restricting the NV12 change for scaler to BXT and KBL
in this series.

v9: Rebased (me)

v10: As of now, NV12 has been tested on Gen9 and Gen10. However,
code is applicable to all GEN >= 9. Hence making
that change to keep it generic.
Comments under v8 is not valid anymore.

v11: Addressed review comments by Shashank Sharma.
For Gen10+, the scaler mode to be set it planar or normal
(single bit). Changed the code to be applicable to all
Gen.

v12: Addressed review comments from Shashank Sharma
For Gen9 (apart from GLK) bits 28:29 to be programmed
in PS_CTRL for NV12. For GLK and Gen10+, bit 29 to be set
for all Planar.

v13: Addressed review comments from Juha-Pekka Heikkila
"NV12 not to be supported by SKL"
Adding Reviewed by tag from Shashank Shamr

v14: Added reviewed by from Juha-Pekka Heikkila

v15: Rebased the series

Tested-by: Clinton Taylor <clinton.a.taylor@intel.com>
Reviewed-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
Reviewed-by: Clinton Taylor <clinton.a.taylor@intel.com>
Signed-off-by: Chandra Konduru <chandra.konduru@intel.com>
Signed-off-by: Nabendu Maiti <nabendu.bikash.maiti@intel.com>
Signed-off-by: Vidya Srinivas <vidya.srinivas@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1523245273-30264-13-git-send-email-vidya.srinivas@intel.com

If the fb format is YUV, enable the plane CSC mode bits
for the conversion.

v2: Addressed review comments from Shashank Sharma
Alignment issue fixed in i915_reg.h

v3: Adding Reviewed By from Shashank Sharma

v4: Rebased the patch. As part of rebasing, re-using
the color series defines which are already merged.
plane_state->base.color_encoding might not be set for
NV12. For now, just using PLANE_COLOR_CSC_MODE_YUV709_TO_RGB709
in glk_plane_color_ctl if format is NV12.

v5: Added reviewed by from Juha-Pekka Heikkila

v6: Rebased the series

Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
Reviewed-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
Signed-off-by: Vidya Srinivas <vidya.srinivas@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1523245273-30264-12-git-send-email-vidya.srinivas@intel.com

Display WA 827 applies to GEN9 (excluede GLK) and CNL.
Switching the plane format from NV12 to RGB and leaving system idle
results in display underrun and corruption.
WA: Set the bit 15 & bit 19 to 1b in the CLKGATE_DIS_PSL
register for the pipe in which NV12 plane is enabled.

v2: Addressed review comments from Maarten and
Juha-Pekka Heikkila. Added reviewed by from
Juha-Pekka Heikkila.

v3: Rebased the series

Reviewed-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
Signed-off-by: Chandra Konduru <chandra.konduru@intel.com>
Signed-off-by: Nabendu Maiti <nabendu.bikash.maiti@intel.com>
Signed-off-by: Vidya Srinivas <vidya.srinivas@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1523245273-30264-11-git-send-email-vidya.srinivas@intel.com

This patch splits skl_compute_wm/ddb functions into two parts.
One adds all affected pipes after the commit to atomic_state structure
and second part does compute the DDB.

v2: Added reviewed by tag from Shashank Sharma

v3: Added reviewed by from Juha-Pekka Heikkila

v4: Rebased the series

v5: Fixed checkpatch error. Changed *changed = true
to (*changed) = true;

Reviewed-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
Signed-off-by: Mahesh Kumar <mahesh1.kumar@intel.com>
Signed-off-by: Vidya Srinivas <vidya.srinivas@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1523245273-30264-10-git-send-email-vidya.srinivas@intel.com

Display Workaround #0826 (SKL:ALL BXT:ALL) & #1059(CNL:A)
Hardware sometimes fails to wake memory from pkg C states fetching the
last few lines of planar YUV 420 (NV12) planes. This causes
intermittent underflow and corruption.
WA: Disable package C states or do not enable latency levels 1 through 7
(WM1 - WM7) on NV12 planes.

v2: Addressed review comments by Maarten.

v3: Adding reviewed by tag from Shashank Sharma

v4: Added reviewed by from Juha-Pekka Heikkila

v5: Rebased the series

Reviewed-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Mahesh Kumar <mahesh1.kumar@intel.com>
Signed-off-by: Vidya Srinivas <vidya.srinivas@intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1523245273-30264-9-git-send-email-vidya.srinivas@intel.com

DDB allocation optimization algorithm requires/assumes ddb allocation for
any memory C-state level DDB value to be as high as level below the
current level. Render decompression requires level WM to be as high as
wm level-0. This patch fulfils both the requirements.

v2: Changed plane_num to plane_id in skl_compute_wm_levels

v3: Addressed review comments from Shashank Sharma
Changed the commit message "statement can be more clear,
"DDB value to be as high as level below " what is level below ?"

v4: Added reviewed by tag from Shashank Sharma

v5: Added reviewed by from Juha-Pekka Heikkila

v6: Rebased the series

Reviewed-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
Signed-off-by: Mahesh Kumar <mahesh1.kumar@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1523245273-30264-8-git-send-email-vidya.srinivas@intel.com

This patch passes skl_wm_level structure itself to watermark
computation function skl_compute_plane_wm function (instead
of its internal parameters). It reduces number of arguments
required to be passed.

v2: Addressed review comments by Shashank Sharma

v3: Adding reviewed by tag from Shashank Sharma

v4: Added reviewed by from Juha-Pekka Heikkila

v5: Rebased the series

Reviewed-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
Signed-off-by: Mahesh Kumar <mahesh1.kumar@intel.com>
Signed-off-by: Vidya Srinivas <vidya.srinivas@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1523245273-30264-7-git-send-email-vidya.srinivas@intel.com

NV12 requires WM calculation for UV plane as well.
UV plane WM should also fulfill all the WM related restrictions.

v2: Addressed review comments from Shashank Sharma.

v3: Addressed review comments from Shashank Sharma
Changed plane_num to plane_id in skl_compute_plane_wm_params
and skl_compute_plane_wm.
Adding reviewed by tag from Shashank Sharma

v4: Added reviewed by from Juha-Pekka Heikkila

v5: Rebased the series

Reviewed-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
Signed-off-by: Mahesh Kumar <mahesh1.kumar@intel.com>
Signed-off-by: Vidya Srinivas <vidya.srinivas@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1523245273-30264-6-git-send-email-vidya.srinivas@intel.com

For YUV 420 Planar formats like NV12,
buffer allocation is done for Y and UV surfaces separately.
For NV12 plane formats, the UV buffer
allocation must be programmed in the Plane Buffer Config register
and the Y buffer allocation must be programmed in the
Plane NV12 Buffer Config register. Both register values
should be verified during verify_wm_state.

v2: Addressed review comments by Maarten.

v3: Addressed review comments by Shashank Sharma.

v4: Adding reviewed by tag from Shashank Sharma

v5: Added reviewed by from Juha-Pekka Heikkila

v6: Rebased the series

Reviewed-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
Signed-off-by: Mahesh Kumar <mahesh1.kumar@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1523245273-30264-5-git-send-email-vidya.srinivas@intel.com

Add support of recognizing DRM_FORMAT_NV12 from plane_format
register value.

v2: Added reviewed by tag from Mika Kahola

v3: Added reviewed by from Juha-Pekka Heikkila

v4: Rebased the series

Reviewed-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
Reviewed-by: Mika Kahola <mika.kahola@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Mahesh Kumar <mahesh1.kumar@intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1523245273-30264-4-git-send-email-vidya.srinivas@intel.com

Current code calculates DDB for planar formats in such a way that we
store DDB of plane-0 in plane 1 & vice-versa.
In order to make this clean this patch refactors WM/DDB calculation for
NV12 planar formats.

v2: Addressed review comments by Maarten

v3: Rebased and addressed review comments by Maarten

v4: Fixed a compilation issue of string replacement is_nv12 to
is_planar

v5: Added reviewed by from Juha-Pekka Heikkila

v6: Rebased the series

Reviewed-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Mahesh Kumar <mahesh1.kumar@intel.com>
Signed-off-by: Vidya Srinivas <vidya.srinivas@intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1523245273-30264-3-git-send-email-vidya.srinivas@intel.com

skl_wm_values struct contains values of pipe/plane DDB only.
so rename it for better readability of code. Similarly
skl_copy_wm_for_pipe copies DDB values.

s/skl_wm_values/skl_ddb_values
s/skl_copy_wm_for_pipe/skl_copy_ddb_for_pipe

Changes since V1:
 - also change name of skl_copy_wm_for_pipe

v2: Added reviewed by from Juha-Pekka Heikkila

v3: Rebased the series

Reviewed-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Mahesh Kumar <mahesh1.kumar@intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1523245273-30264-2-git-send-email-vidya.srinivas@intel.com

When doing a modeset where the sink is transitioning from D3 to D0 , it
would sometimes be possible for the initial power_up_phy() to start
timing out. This would only be observed in the last action before the
sink went into D3 mode was intel_dp_sink_dpms(DRM_MODE_DPMS_OFF). We
originally thought this might be an issue with us accidentally shutting
off the aux block when putting the sink into D3, but since the DP spec
mandates that sinks must wake up within 1ms while we have 100ms to
respond to an ESI irq, this didn't really add up. Turns out that the
problem is more subtle then that:

It turns out that the timeout is from us not enabling DPMS on the MST
hub before actually trying to initiate sideband communications. This
would cause the first sideband communication (power_up_phy()), to start
timing out because the sink wasn't ready to respond. Afterwards, we
would call intel_dp_sink_dpms(DRM_MODE_DPMS_ON) in
intel_ddi_pre_enable_dp(), which would actually result in waking up the
sink so that sideband requests would work again.

Since DPMS is what lets us actually bring the hub up into a state where
sideband communications become functional again, we just need to make
sure to enable DPMS on the display before attempting to perform sideband
communications.

Changes since v1:
- Remove comment above if (!intel_dp->is_mst) - vsryjala
- Move intel_dp_sink_dpms() for MST into intel_dp_post_disable_mst() to
  keep enable/disable paths symmetrical
- Improve commit message - dhnkrn
Changes since v2:
- Only send DPMS off when we're disabling the last sink, and only send
  DPMS on when we're enabling the first sink - dhnkrn
Changes since v3:
- Check against is_mst, not intel_dp->is_mst - dhnkrn/vsyrjala

Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Tested-by: Laura Abbott <labbott@redhat.com>
Cc: stable@vger.kernel.org
Fixes: ad260ab3 ("drm/i915/dp: Write to SET_POWER dpcd to enable MST hub.")
Link: https://patchwork.freedesktop.org/patch/msgid/20180407011053.22437-1-lyude@redhat.com

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: Chris 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: Michel Thierry <michel.thierry@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180406220354.18911-2-chris@chris-wilson.co.uk

If we are resetting just one engine, we know it has stalled. So we can
pass the stalled parameter directly to i915_gem_reset_engine(), which
alleviates the necessity to poke at the generic engine->hangcheck.stalled
magic variable, leaving that under control of hangcheck as its name
implies. Other than simplifying by removing the indirect parameter along
this path, this allows us to introduce new reset mechanisms that run
independently of hangcheck.

Signed-off-by: Chris 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: Michel Thierry <michel.thierry@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180406220354.18911-1-chris@chris-wilson.co.uk

We will want to park GEM before disengaging the drive^W^W^W unwedging.
Since we already do the work for idling, expose the guts as a new
function that we can then reuse.

v2: Just skip if already parked; makes it more forgiving to use by
future callers.
v3: Extract mark_busy, rename it to i915_gem_unpark and place it next to
i915_gem_park so that we can evaluate it for symmetry more easily.
Calling GEM from inside i915_request looks to be a bit of a layering
violation, for the moment I am imaging them as being notify_cb.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Sagar Arun Kamble <sagar.a.kamble@intel.com>
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
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180406155144.27791-1-chris@chris-wilson.co.uk