Being inside a spinlock signaling that the hardware just completed a
request doesn't prevent a second thread already spotting that the
request is complete, freeing it and reallocating it! The code currently
tries to prevent this using RCU -- but that only prevents the request
from being freed, it doesn't prevent us from reallocating it - that
requires us to take a reference.

[  206.922985] BUG: spinlock already unlocked on CPU#4, gem_exec_parall/7796
[  206.922994]  lock: 0xffff8801c6047120, .magic: dead4ead, .owner: <none>/-1, .owner_cpu: -1
[  206.923000] CPU: 4 PID: 7796 Comm: gem_exec_parall Not tainted 4.10.0-CI-Patchwork_4008+ #1
[  206.923006] Hardware name: System manufacturer System Product Name/Z170M-PLUS, BIOS 1805 06/20/2016
[  206.923012] Call Trace:
[  206.923014]  <IRQ>
[  206.923019]  dump_stack+0x67/0x92
[  206.923023]  spin_dump+0x73/0xc0
[  206.923027]  do_raw_spin_unlock+0x79/0xb0
[  206.923031]  _raw_spin_unlock_irqrestore+0x27/0x60
[  206.923042]  dma_fence_signal+0x160/0x230
[  206.923060]  notify_ring+0xae/0x2e0 [i915]
[  206.923073]  ? ibx_hpd_irq_handler+0xc0/0xc0 [i915]
[  206.923086]  gen8_gt_irq_handler+0x219/0x290 [i915]
[  206.923100]  gen8_irq_handler+0x8e/0x6b0 [i915]
[  206.923105]  __handle_irq_event_percpu+0x58/0x370
[  206.923109]  handle_irq_event_percpu+0x1e/0x50
[  206.923113]  handle_irq_event+0x34/0x60
[  206.923117]  handle_edge_irq+0xbe/0x150
[  206.923122]  handle_irq+0x15/0x20
[  206.923126]  do_IRQ+0x63/0x130
[  206.923142]  ? i915_mutex_lock_interruptible+0x39/0x140 [i915]
[  206.923148]  common_interrupt+0x90/0x90
[  206.923153] RIP: 0010:osq_lock+0x77/0x110
[  206.923157] RSP: 0018:ffffc90001cabaa0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff6e
[  206.923164] RAX: 0000000000000000 RBX: ffff880236d1abc0 RCX: ffff8801ef642fc0
[  206.923169] RDX: ffff8801ef6427c0 RSI: ffffffff81c6e7fd RDI: ffffffff81c7c848
[  206.923175] RBP: ffffc90001cabab8 R08: 00000000692bb19b R09: 08c1493200000000
[  206.923180] R10: 0000000000000001 R11: 0000000000000001 R12: ffff880236cdabc0
[  206.923185] R13: ffff8802207f00b0 R14: ffffffffa00b7cd9 R15: ffff8802207f0070
[  206.923191]  </IRQ>
[  206.923206]  ? i915_mutex_lock_interruptible+0x39/0x140 [i915]
[  206.923213]  __mutex_lock+0x649/0x990
[  206.923217]  ? __mutex_lock+0xb0/0x990
[  206.923221]  ? _raw_spin_unlock+0x2c/0x50
[  206.923226]  ? __pm_runtime_resume+0x56/0x80
[  206.923242]  ? i915_mutex_lock_interruptible+0x39/0x140 [i915]
[  206.923249]  mutex_lock_interruptible_nested+0x16/0x20
[  206.923264]  i915_mutex_lock_interruptible+0x39/0x140 [i915]
[  206.923270]  ? __pm_runtime_resume+0x56/0x80
[  206.923285]  i915_gem_do_execbuffer.isra.15+0x442/0x1d10 [i915]
[  206.923291]  ? __lock_acquire+0x449/0x1b50
[  206.923296]  ? __might_fault+0x3e/0x90
[  206.923301]  ? __might_fault+0x87/0x90
[  206.923305]  ? __might_fault+0x3e/0x90
[  206.923320]  i915_gem_execbuffer2+0xb5/0x220 [i915]
[  206.923327]  drm_ioctl+0x200/0x450
[  206.923341]  ? i915_gem_execbuffer+0x330/0x330 [i915]
[  206.923348]  do_vfs_ioctl+0x90/0x6e0
[  206.923352]  ? __fget+0x108/0x200
[  206.923356]  ? expand_files+0x2b0/0x2b0
[  206.923361]  SyS_ioctl+0x3c/0x70
[  206.923365]  entry_SYSCALL_64_fastpath+0x1c/0xb1
[  206.923369] RIP: 0033:0x7fdd75fc6357
[  206.923373] RSP: 002b:00007fdd20e59bf8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
[  206.923380] RAX: ffffffffffffffda RBX: ffffffff81481ff3 RCX: 00007fdd75fc6357
[  206.923385] RDX: 00007fdd20e59c70 RSI: 0000000040406469 RDI: 0000000000000003
[  206.923390] RBP: ffffc90001cabf88 R08: 0000000000000040 R09: 00000000000003f7
[  206.923396] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
[  206.923401] R13: 0000000000000003 R14: 0000000040406469 R15: 0000000001cf9cb0
[  206.923408]  ? __this_cpu_preempt_check+0x13/0x20

Fixes: 56299fb7 ("drm/i915: Signal first fence from irq handler if complete")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=100051Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170303144557.4815-1-chris@chris-wilson.co.ukReviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>

Add tracepoints for display FIFO underruns. Makes it more convenient to
correlate the underruns with other display tracepoints.

v2: s/i915/intel/ in the tracepoint name
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302171508.1666-19-ville.syrjala@linux.intel.com

Add a tracepoint for observing changes in the cxsr state. The tracepoint
will dump out the frame and scanline counters for each pipe so that the
information can be compared with eg. plane update tracepoints.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302171508.1666-18-ville.syrjala@linux.intel.com

Add tracepoints for observing the WM/FIFO programming on VLV/CHV. When
compared with the plane and pipe update tracepoints this can be used
to verify that everything is performed in the right sequence.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302171508.1666-17-ville.syrjala@linux.intel.com

Add tracepoints for plane programming. The tracepoints will dump
the frame and scanline counters, so this can be used to verify eg. that
the plane gets reprogrammed at the right time with respect to watermark
programming (if we have appropriate tracepoints for that as well).

v2: Rebase due to legacy cursor changes
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302171508.1666-16-ville.syrjala@linux.intel.com

We now compute the watermarks correctly, so just return an error if we
can't support the configuration.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302171508.1666-15-ville.syrjala@linux.intel.com

On VLV/CHV enabling sprite0 when sprite1 has already been enabled may
lead to an underrun. This only happens when sprite0 FIFO size is zero
prior to enabling it. Hence an effective workaround is to always
allocate at least one cacheline for sprite0 when sprite1 is active.

I've not observed this sort of failure during any other type of plane
enable/disable sequence.

v2: s/noninverted/raw/ for consistency with other platforms

Testcase: igt/kms_plane_blinker
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302171508.1666-14-ville.syrjala@linux.intel.com

Clear out the watermark for all disabled planes to 0. This is required
to avoid falsely thinking that the inherited watermarks are bogus in
case the watermark is actually higher than the FIFO size.

v2: s/noninverted/raw/ for consistency with other platforms
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302171508.1666-13-ville.syrjala@linux.intel.com

Now that vlv/chv have more proper wm programming support, let's reduce
the the update_wm_{pre,post} flags to only cover the pre-ilk platforms.
When we finally convert those as well we can drop these flags entirely.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302171508.1666-12-ville.syrjala@linux.intel.com

Remove crtc->wm.cxsr_allowed and just rely on crtc_state->disable_cxsr
instead. This was used only by vlv/chv to indicate whether to enable
cxsr in the wm computation. That doesn't really work anymore, and as far
as the optimal watermarks go we'll just consider the number of planes
and the current pipe, and for the intermediate watermarks we'll also
start to consider disable_cxsr which is set appropriately when planes
are being enabled/disabled.

We'll also flip over the crtc_state->wm.need_postvbl_update setup so
that it's the wm code that will set it. Previously the generic code set
it up, and then the wm code cleared it again if it thought it's not
needed after all.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302171508.1666-11-ville.syrjala@linux.intel.com

Since the watermark registers arent double buffered on VLV/CHV, we'll
need to play around with intermediate watermarks same was as we do on
ILK-BDW.

The watermark registers on VLV/CHV contain inverted values, so to find
the intermediate watermark value we just take the minimum of the
active and optimal values. This also means that, unlike ILK-BDW,
there's no chance that we'd fail to find a working intermediate
watermarks. As long as both the active and optimal watermarks are valid
the intermediate watermarks will come out valid as well.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302171508.1666-10-ville.syrjala@linux.intel.com

Check whether anything relevant has actually change when we compute new
watermarks for each plane in the state. If the watermarks for no
primary/sprite planes changed we don't have to recompute the FIFO split
or reprogram the DSBARB registers. And even the cursor watermarks didn't
change we can skip the merge+invert step between all the planes on
the pipe as well.

v2: s/noninverted/raw/ for consistency with other platforms
v3: Drop duplicated vlv_get_fifo_size() call during init
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302171508.1666-9-ville.syrjala@linux.intel.com

Start computing the vlv/chv watermarks the atomic way, from the
.compute_pipe_wm() hook. We'll recompute the actual watermarks
for only planes that are part of the state, the other planes will
keep their watermark from the last time it was computed.

And the actual watermark programming will happen from the
.initial_watermarks() hook. For now we'll just compute the
optimal watermarks, and we'll hook up the intermediate
watermarks properly later.

The DSPARB registers responsible for the FIFO paritioning are
double buffered, so they will be programming from
intel_begin_crtc_commit().

v2: s/noninverted/raw/ for consistency with other platforms
    s/vlv_plane_wm_set/vlv_raw_plane_wm_set/ for clarity
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302171508.1666-8-ville.syrjala@linux.intel.com

Let's compute the watermarks first and the FIFO size second. This way we
can make sure the FIFO split is the most accommodating to the watermarks.
Previously we could have potentially computed a FIFO split that couldn't
accommodate the PM2 watermarks simply due to a bad split even if the
total FIFO size would have been sufficient.

It'll also allow us to avoid recomputing the wms for all planes whenever
the FIFO split would change. Thus we don't have to add any extra planes
to the state when the FIFO needs to be repartitioned.

To help with this we'll keep around copies of the non-inverted
watermarks in the crtc state. For now that doesn't help too much, but
once we start to do the watermark computation only for the planes
that change we'll need the non-inverted values around for the other
planes.

v2: s/noninverted/raw/ for consistency with other platforms
    Fix the memset() of the "raw" watermarks
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302171508.1666-7-ville.syrjala@linux.intel.com

Move the vlv/chv FIFO size tracking into the crtc_state. As with the wms
for now this just acts as temporary storage.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302171508.1666-6-ville.syrjala@linux.intel.com

Relocate the vlv/chv wm state to live under intel_crtc_state. Note
that for now this just behaves as a temporary storage. But it'll be
easier to conver the thing over to properly pre-computing the state
when it's already in the right place.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302171508.1666-5-ville.syrjala@linux.intel.com

In an effort to make the vlv/chv wm code look and behave more like the
ilk+ code, let's move the current active wms next to the
corresponding ilk wms.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302171508.1666-4-ville.syrjala@linux.intel.com

Track the plane fifo sizes under intel_crtc instead of under each
intel_plane. Avoids looping over the planes in a bunch of places,
and later we'll move this tracking into the crtc state properly.

v2: Nuke intel_plane_wm_parameters (Maarten)
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302171508.1666-3-ville.syrjala@linux.intel.com

In a lot of place we wish to know which planes on the crtc are actually
visible, or how many of them there are. Let's start tracking that in a
bitmask in the crtc state.

We already track enabled planes (ie. ones with an fb and crtc specified by
the user) but that's not quite the same thing as enabled planes may
still end up being invisible due to clipping and whatnot.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302171508.1666-2-ville.syrjala@linux.intel.com

If we manage to tangle errorpaths and get call to callbacks,
it is better to defensively keep them as null until object init is
finished so that we get clean null deref on callsite,
instead of more cryptic wreckage with partly initialized vm objects.
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1488295691-9404-5-git-send-email-mika.kuoppala@intel.com

The term legacy is subjective. Use 3lvl and 4lvl
where appropriate.
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1488295691-9404-4-git-send-email-mika.kuoppala@intel.com

If we setup the vm size early, we can use the newly introduced
i915_vm_is_48bit() in majority of callsites wanting to know the vm size.

As we operate either with 3lvl or 4lvl page table structure,
wrap the vm size query inside a function which tells us if
4lvl setup is needed for particular vm, as the following
code uses the function names where level is noted.

v2: use_4lvl (Chris)
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1488295691-9404-3-git-send-email-mika.kuoppala@intel.com

Don't mark pdps clear if never do the necessary actions
with the hardware to make them clear.

v2: totally get rid of confusing ppgtt bool (Chris)
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1488295691-9404-2-git-send-email-mika.kuoppala@intel.com

The macro takes a vm pointer at some sites, and dev_priv on others
We were saved as the internal macro never deferences the pointer
given.

As the number of pdpes depend on vm configuration, make it
as a inline function that accepts vm pointer.

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wsilon.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1488295691-9404-1-git-send-email-mika.kuoppala@intel.com

The code to check for execlists completion is generic, so move it to
intel_engine_cs.c, where we can reuse the new intel_engine_is_idle().
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20170303121947.20482-2-chris@chris-wilson.co.ukReviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>

During reset_all_global_seqno() on seqno rollover, we have to update the
HWS. This causes all in flight requests to be completed, so first we
wait. However, we were only waiting for the requests themselves to be
completed and clearing out the waiter rbtrees - what I had missed was
the extra reference in execlists->port[]. Since commit fe9ae7a3
("drm/i915/execlists: Detect an out-of-order context switch") we can
detect when the request is retired before the context switch interrupt
is completed. The impact should be neglible outside of debugging.

Testcase: igt/gem_exec_whisper
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170303121947.20482-1-chris@chris-wilson.co.ukReviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>

The logic to enable a DDI in intel_mst_pre_enable_dp() is essentially
the same as in intel_ddi_pre_enable_dp(). So reuse the latter function
by calling the post_disable hook on the intel_dig_port instead of
duplicating that code.

v2: Don't oops because of a NULL encoder->crtc. (Ville)
v3: Warn for MST + PORT_E too. (Ville)
Cc: Imre Deak <imre.deak@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NAnder Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302125857.14665-8-ander.conselvan.de.oliveira@intel.com

Remove direct usages of intel_crtc->config from the DDI code. Functions
that didn't yet take a pipe_config as an argument were coverted to do
so.

v2: s/pipe_config/const crtc_state/ (Ville)
  - take crtc from crtc_state. (Ville)
Signed-off-by: NAnder Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302125857.14665-7-ander.conselvan.de.oliveira@intel.com

Pass intel_crtc to functions intel_ddi_enable_transcoder_func(),
intel_ddi_set_pipe_settings() and intel_ddi_set_vc_payload_alloc(),
instead of the generic crtc type. By changing the functions
intel_ddi_get_crtc_encoder() so that it receives an intel_crtc
parameter, there is no need for the drm_crtc in the callers.
Signed-off-by: NAnder Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302125857.14665-6-ander.conselvan.de.oliveira@intel.com

It is preferred to pass pipe_config to functions instead of accessing
crtc->config directly. Follow suit and pass pipe_config to the fdi link
train functions.

v2: Add const; s/pipe_config/crtc_state/ (Ville)
Signed-off-by: NAnder Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302125857.14665-5-ander.conselvan.de.oliveira@intel.com

Using crtc->config directly is being removed in favor of passing a
pipe_config. Follow the trend and pass pipe_config to pch_enable()
functions.

v2: s/pipe_config/crtc_state/ (Ville)
  - constify crtc_state. (Ville)
  - take crtc from crtc_state. (Ville)
Signed-off-by: NAnder Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302125857.14665-4-ander.conselvan.de.oliveira@intel.com

The function intel_lpt_pch_enable() needs an intel_crtc so pass that
instead of the generic crtc type.
Signed-off-by: NAnder Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302125857.14665-3-ander.conselvan.de.oliveira@intel.com

The implementation of the fdi_link_train() hooks need an intel_crtc so
just pass that instead of the generic crtc type.
Signed-off-by: NAnder Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302125857.14665-2-ander.conselvan.de.oliveira@intel.com

Check timer_pending() as well as work_pending() to see if the timer for
the hangcheck has already expired and the work is pending execution on
some list somewhere.

v2: Use a more compact if-chain
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170303090056.19973-1-chris@chris-wilson.co.ukReviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>

Adding to the tail of the client request list as the only other user is
in the throttle ioctl that iterates forwards over the list. It only
needs protection against deletion of a request as it reads it, it simply
won't see a new request added to the end of the list, or it would be too
early and rejected. We can further reduce the number of spinlocks
required when throttling by removing stale requests from the client_list
as we throttle.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302122525.19675-1-chris@chris-wilson.co.uk

Currently ILK-BDW explicitly disable LP1+ watermarks from their
.init_clock_gating() hooks. Unfortunately that hook gets called way too
late since by that time we've already initialized all the watermark
state tracking which then gets out of sync with the hardware state.

We may eventually want to consider killing off the explicit LP1+
disable from .init_clock_gating(). In the meantime however, we can
avoid the problem by reordering the init sequence such that
intel_modeset_init_hw()->intel_init_clock_gating() gets called
prior to the hardware state takeover.

I suppose prior to the two stage watermark programming we were
magically saved by something that forced the watermarks to be
reprogrammed fully after .init_clock_gating() got called. But
now that no longer happens.

Note that the diff might look a bit odd as it kills off one
call of intel_update_cdclk(), but that's fine because
intel_modeset_init_hw() does the exact same thing. Previously
we just did it twice.

Actually even this new init sequence is pretty bogus as
.init_clock_gating() really should be called before any gem
hardware init since it can  configure various clock gating
workarounds and whatnot that affect the GT side as well. Also
intel_modeset_init() really should get split up into better
defined init stages. Another "fun" detail is that
intel_modeset_gem_init() is where RPS/RC6 gets configured.
Why that is done from the display code is beyond me. I've
decided to leave all this be for now, and just try to fix
the init sequence enough for watermarks to work.

Cc: stable@vger.kernel.org
Cc: Gabriele Mazzotta <gabriele.mzt@gmail.com>
Cc: David Purton <dcpurton@marshwiggle.net>
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reported-by: NGabriele Mazzotta <gabriele.mzt@gmail.com>
Reported-by: NDavid Purton <dcpurton@marshwiggle.net>
Tested-by: NGabriele Mazzotta <gabriele.mzt@gmail.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=96645
Fixes: ed4a6a7c ("drm/i915: Add two-stage ILK-style watermark programming (v11)")
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170220140443.30891-1-ville.syrjala@linux.intel.comReviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Useful for double checking that the device is powered up when it hung,
include both the status of the power management and our rpm wakelock.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302151544.16915-1-chris@chris-wilson.co.ukReviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>

Whilst investigating some mysterious failures with hangcheck not running
during gem_busy/basic-hang-default, the question is why did we decide to
cancel the retire_work (which queues the hangcheck)? That decision is
based around GT activity, so include that information in the debug
report.

v2: Include the GT awake status in the error state
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302150356.9713-1-chris@chris-wilson.co.ukReviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>

__i915_guc_submit may be, despite my assertion, called from outside of
an irq-safe spinlock so we need to use a full spin_lock_irqsave and not
cheat using a spin_lock. (The initial notify callback from the completed
fence is called before the spinlock is taken to wake up all waiters and
call their callbacks.)

[   48.166581] kernel BUG at drivers/gpu/drm/i915/i915_guc_submission.c:527!
[   48.166617] invalid opcode: 0000 [#1] PREEMPT SMP
[   48.166644] Modules linked in: i915 prime_numbers x86_pkg_temp_thermal intel_powerclamp coretemp crct10dif_pclmul crc32_pclmul ghash_clmulni_intel mei_me mei i2c_i801 netconsole i2c_hid [last unloaded: i915]
[   48.166733] CPU: 2 PID: 5 Comm: kworker/u8:0 Tainted: G     U          4.10.0nightly-170302-guc_scrub+ #19
[   48.166778] Hardware name:                  /NUC6i5SYB, BIOS SYSKLi35.86A.0054.2016.0930.1102 09/30/2016
[   48.166835] Workqueue: i915 __intel_autoenable_gt_powersave [i915]
[   48.166865] task: ffff88084ab7cf40 task.stack: ffffc90000064000
[   48.166921] RIP: 0010:__i915_guc_submit+0x1e6/0x2a0 [i915]
[   48.166953] RSP: 0018:ffffc90000067c80 EFLAGS: 00010202
[   48.166979] RAX: 0000000000000202 RBX: ffff8808465e0c68 RCX: 0000000000000201
[   48.167016] RDX: 0000000080000201 RSI: ffff88084ab7d798 RDI: ffff88082b8a8040
[   48.167054] RBP: ffffc90000067cd8 R08: 0000000000000001 R09: 0000000000000000
[   48.167085] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88082b8a8148
[   48.167126] R13: 0000000000000000 R14: ffff88082f440000 R15: ffff88082e85e660
[   48.167156] FS:  0000000000000000(0000) GS:ffff88086ed00000(0000) knlGS:0000000000000000
[   48.167195] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   48.167226] CR2: 000055862ffcdc2c CR3: 0000000001e0f000 CR4: 00000000003406e0
[   48.167257] Call Trace:
[   48.168112]  ? trace_hardirqs_on+0xd/0x10
[   48.168966]  ? _raw_spin_unlock_irqrestore+0x4a/0x80
[   48.169831]  i915_guc_submit+0x1a/0x20 [i915]
[   48.170680]  submit_notify+0x89/0xc0 [i915]
[   48.171512]  __i915_sw_fence_complete+0x175/0x220 [i915]
[   48.172340]  i915_sw_fence_complete+0x2a/0x50 [i915]
[   48.173158]  i915_sw_fence_commit+0x21/0x30 [i915]
[   48.173968]  __i915_add_request+0x238/0x530 [i915]
[   48.174764]  __intel_autoenable_gt_powersave+0x8b/0xb0 [i915]
[   48.175549]  process_one_work+0x218/0x690
[   48.176318]  ? process_one_work+0x197/0x690
[   48.177183]  worker_thread+0x4e/0x4a0
[   48.178039]  kthread+0x10c/0x140
[   48.178878]  ? process_one_work+0x690/0x690
[   48.179718]  ? kthread_create_on_node+0x40/0x40
[   48.180568]  ret_from_fork+0x31/0x40
[   48.181423] Code: 02 00 00 43 89 84 ae 50 11 00 00 e8 75 01 62 e1 48 83 c4 30 5b 41 5c 41 5d 41 5e 41 5f 5d c3 48 c1 e0 20 48 09 c2 49 89 d0 eb 82 <0f> 0b 0f 0b 0f 0b 0f 0b 0f 0b 0f 0b 49 c1 e8 20 44 89 43 34 4a
[   48.183336] RIP: __i915_guc_submit+0x1e6/0x2a0 [i915] RSP: ffffc90000067c80
Reported-by: NArkadiusz Hiler <arkadiusz.hiler@intel.com>
Fixes: 349ab919 ("drm/i915/guc: Make wq_lock irq-safe")
Fixes: 67b807a8 ("drm/i915: Delay disabling the user interrupt for breadcrumbs")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Arkadiusz Hiler <arkadiusz.hiler@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302145323.12886-1-chris@chris-wilson.co.ukReviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NArkadiusz Hiler <arkadiusz.hiler@intel.com>
Tested-by: NArkadiusz Hiler <arkadiusz.hiler@intel.com>

assert_spin_locked() becomes an unconditionally compiled BUG_ON(),
adding debug code right into the heart of critical routines like
interrupt handlers.

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

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

Small saving for release; hopefully more instructive in debug.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170302132801.599-1-chris@chris-wilson.co.ukReviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>