This effectively reverts

commit 8e5fd599
Author: Ville Syrjälä <ville.syrjala@linux.intel.com>
Date:   Wed Apr 9 13:28:50 2014 +0300

    drm/i915/chv: Make CHV irq handler loop until all interrupts are consumed

as under continuous execlists load we can saturate the IRQ handler,
destablising the tsc clock and triggering the NMI watchdog to declare a hung
CPU.

[  552.756051] clocksource: timekeeping watchdog on CPU0: Marking clocksource 'tsc' as unstable because the skew is too large:
[  552.756080] clocksource:                       'refined-jiffies' wd_now: 10003b480 wd_last: 10003b28c mask: ffffffff
[  552.756091] clocksource:                       'tsc' cs_now: d55d31aa50 cs_last: d17446166c mask: ffffffffffffffff
[  552.756210] clocksource: Switched to clocksource refined-jiffies
[  575.217870] NMI watchdog: Watchdog detected hard LOCKUP on cpu 1
[  575.217893] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.5.0-rc7+ #18
[  575.217905] Hardware name:                  /NUC5CPYB, BIOS PYBSWCEL.86A.0027.2015.0507.1758 05/07/2015
[  575.217915]  0000000000000000 ffff88027fd05bc0 ffffffff81288c6d 0000000000000000
[  575.217935]  0000000000000001 ffff88027fd05be0 ffffffff810e72d1 0000000000000000
[  575.217951]  ffff88027fd05c80 ffff88027fd05c20 ffffffff81114b60 0000000181015f1e
[  575.217967] Call Trace:
[  575.217973]  <NMI>  [<ffffffff81288c6d>] dump_stack+0x4f/0x72
[  575.217994]  [<ffffffff810e72d1>] watchdog_overflow_callback+0x151/0x160
[  575.218003]  [<ffffffff81114b60>] __perf_event_overflow+0xa0/0x1e0
[  575.218016]  [<ffffffff811154c4>] perf_event_overflow+0x14/0x20
[  575.218028]  [<ffffffff8101d2ca>] intel_pmu_handle_irq+0x1da/0x460
[  575.218042]  [<ffffffff814a8aae>] ? poll_idle+0x3e/0x70
[  575.218052]  [<ffffffff814a8aae>] ? poll_idle+0x3e/0x70
[  575.218064]  [<ffffffff81014ae8>] perf_event_nmi_handler+0x28/0x50
[  575.218075]  [<ffffffff81007540>] nmi_handle+0x60/0x130
[  575.218086]  [<ffffffff814a8aae>] ? poll_idle+0x3e/0x70
[  575.218096]  [<ffffffff810079c0>] do_nmi+0x140/0x470
[  575.218108]  [<ffffffff81559ec7>] end_repeat_nmi+0x1a/0x1e
[  575.218119]  [<ffffffff814a8aae>] ? poll_idle+0x3e/0x70
[  575.218129]  [<ffffffff814a8aae>] ? poll_idle+0x3e/0x70
[  575.218139]  [<ffffffff814a8aae>] ? poll_idle+0x3e/0x70
[  575.218148]  <<EOE>>  [<ffffffff814a8353>] cpuidle_enter_state+0xf3/0x2f0
[  575.218164]  [<ffffffff814a8587>] cpuidle_enter+0x17/0x20
[  575.218175]  [<ffffffff810aaa3a>] call_cpuidle+0x2a/0x40
[  575.218185]  [<ffffffff810aade3>] cpu_startup_entry+0x273/0x330
[  575.218196]  [<ffffffff81033a1e>] start_secondary+0x10e/0x130

However, not servicing all available IIR within the handler does hurt the
throughput of pathological nop execbuf by about 20%, with a similar effect
upon the dispatch latency of a series of execbuf.

v2: use do {} while(0) for a smaller patch, and easier to revert again

I have reasonable confidence that we do not miss GT interrupts (as
execlists provides a stress case with a failure mechanism easily
detected by igt), however I have less confidence about all the other
sources of interrupts and worry that may lose a display hotplug
interrupt, for example.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=93467
Testcase: igt/gem_exec_nop/basic # requires NMI watchdog
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Antti Koskipää <antti.koskipaa@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: stable@vger.kernel.org
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1457946117-6714-1-git-send-email-chris@chris-wilson.co.uk
(cherry picked from commit 579de73b)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

Since we need MST devices ready before we try to resume displays,
calling this after intel_display_resume() can result in some issues with
various laptop docks where the monitor won't turn back on after
suspending the system.

This order was originally changed in

	commit e7d6f7d7 ("drm/i915: resume MST after reading back hw state")

In order to fix some unclaimed register errors, however the actual cause
of those has since been fixed.

CC: stable@vger.kernel.org
Signed-off-by: NLyude <cpaul@redhat.com>
[danvet: Resolve conflicts with locking changes.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
(cherry picked from commit a16b7658)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

After unplugging a DP MST display from the system, we have to go through
and destroy all of the DRM connectors associated with it since none of
them are valid anymore. Unfortunately, intel_dp_destroy_mst_connector()
doesn't do a good enough job of ensuring that throughout the destruction
process that no modesettings can be done with the connectors. As it is
right now, intel_dp_destroy_mst_connector() works like this:

* Take all modeset locks
* Clear the configuration of the crtc on the connector, if there is one
* Drop all modeset locks, this is required because of circular
  dependency issues that arise with trying to remove the connector from
  sysfs with modeset locks held
* Unregister the connector
* Take all modeset locks, again
* Do the rest of the required cleaning for destroying the connector
* Finally drop all modeset locks for good

This only works sometimes. During the destruction process, it's very
possible that a userspace application will attempt to do a modesetting
using the connector. When we drop the modeset locks, an ioctl handler
such as drm_mode_setcrtc has the oppurtunity to take all of the modeset
locks from us. When this happens, one thing leads to another and
eventually we end up committing a mode with the non-existent connector:

	[drm:intel_dp_link_training_clock_recovery [i915]] *ERROR* failed to enable link training
	[drm:intel_dp_aux_ch] dp_aux_ch timeout status 0x7cf0001f
	[drm:intel_dp_start_link_train [i915]] *ERROR* failed to start channel equalization
	[drm:intel_dp_aux_ch] dp_aux_ch timeout status 0x7cf0001f
	[drm:intel_mst_pre_enable_dp [i915]] *ERROR* failed to allocate vcpi

And in some cases, such as with the T460s using an MST dock, this
results in breaking modesetting and/or panicking the system.

To work around this, we now unregister the connector at the very
beginning of intel_dp_destroy_mst_connector(), grab all the modesetting
locks, and then hold them until we finish the rest of the function.

CC: stable@vger.kernel.org
Signed-off-by: NLyude <cpaul@redhat.com>
Signed-off-by: NRob Clark <rclark@redhat.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1458155884-13877-1-git-send-email-cpaul@redhat.com
(cherry picked from commit 1f771755)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

Drivers, especially i915.ko, can fail during the initial migration of a
dma-buf for CPU access. However, the error code from the driver was not
being propagated back to ioctl and so userspace was blissfully ignorant
of the failure. Rendering corruption ensues.

Whilst fixing the ioctl to return the error code from
dma_buf_start_cpu_access(), also do the same for
dma_buf_end_cpu_access().  For most drivers, dma_buf_end_cpu_access()
cannot fail. i915.ko however, as most drivers would, wants to avoid being
uninterruptible (as would be required to guarrantee no failure when
flushing the buffer to the device). As userspace already has to handle
errors from the SYNC_IOCTL, take advantage of this to be able to restart
the syscall across signals.

This fixes a coherency issue for i915.ko as well as reducing the
uninterruptible hold upon its BKL, the struct_mutex.

Fixes commit c11e391d
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Thu Feb 11 20:04:51 2016 -0200

    dma-buf: Add ioctls to allow userspace to flush

Testcase: igt/gem_concurrent_blit/*dmabuf*interruptible
Testcase: igt/prime_mmap_coherency/ioctl-errors
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Tiago Vignatti <tiago.vignatti@intel.com>
Cc: Stéphane Marchesin <marcheu@chromium.org>
Cc: David Herrmann <dh.herrmann@gmail.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Daniel Vetter <daniel.vetter@intel.com>
CC: linux-media@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linaro-mm-sig@lists.linaro.org
Cc: intel-gfx@lists.freedesktop.org
Cc: devel@driverdev.osuosl.org
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1458331359-2634-1-git-send-email-chris@chris-wilson.co.uk

CI runs with DEBUG_WW_MUTEX_SLOWPATH, so -EDEADLK occurs a lot more.
Handle the case where drm_atomic_commit fails with -EDEADLK correctly.
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/56D3FEF1.6070306@linux.intel.comReviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
(cherry picked from commit 3ba86073)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

After the GMBUS transfer times out, we set force_bit=1 and
return -EAGAIN expecting the i2c core to call the .master_xfer
hook again so that we will retry the same transfer via bit-banging.
This is in case the gmbus hardware is somehow faulty.

Unfortunately we left adapter->retries to 0, meaning the i2c core
didn't actually do the retry. Let's tell the core we want one retry
when we return -EAGAIN.

Note that i2c-algo-bit also uses this retry count for some internal
retries, so we'll end up increasing those a bit as well.

Cc: Jani Nikula <jani.nikula@intel.com>
Cc: drm-intel-fixes@lists.freedesktop.org
Fixes: bffce907 ("drm/i915: abstract i2c bit banging fallback in gmbus xfer")
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1457366220-29409-2-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NJani Nikula <jani.nikula@intel.com>
(cherry picked from commit 8b1f165a)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

The recent commit [0bdf5a05: drm/i915: Add reverse mapping between
port and intel_encoder] introduced a reverse mapping to retrieve
intel_dig_port object from the port number.  The code assumed that the
port vs intel_dig_port are 1:1 mapping.  But in reality, this was a
too naive assumption.

As Martin reported about the missing HDMI audio on his SNB machine,
pre-HSW chips may have multiple intel_dig_port objects corresponding
to the same port.  Since we assign the mapping statically at the init
time and the multiple objects override the map, it may not match with
the actually enabled output.

This patch tries to address the regression above.  The reverse mapping
is provided basically only for the audio callbacks, so now we set /
clear the mapping dynamically at enabling and disabling HDMI/DP audio,
so that we can always track the latest and correct object
corresponding to the given port.

Fixes: 0bdf5a05 ('drm/i915: Add reverse mapping between port and intel_encoder')
Reported-and-tested-by: NMartin Kepplinger <martink@posteo.de>
Cc: drm-intel-fixes@lists.freedesktop.org
Signed-off-by: NTakashi Iwai <tiwai@suse.de>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Tested-by: NMartin Kepplinger <martink@posteo.de>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1456324522-21591-1-git-send-email-tiwai@suse.de
(cherry picked from commit 9dfbffcf)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

commit 09731280
Author: Imre Deak <imre.deak@intel.com>
Date:   Wed Feb 17 14:17:42 2016 +0200

    drm/i915: Add helper to get a display power ref if it was already enabled

left the rpm wakelock assertions unbalanced if CONFIG_PM was disabled as
intel_runtime_pm_get_if_in_use() would return true without incrementing
the local bookkeeping required for the assertions.

Fixes: 09731280 ("drm/i915: Add helper to get a display power ref if it was already enabled")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
CC: Mika Kuoppala <mika.kuoppala@intel.com>
CC: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
CC: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1456434628-22574-1-git-send-email-chris@chris-wilson.co.ukReviewed-by: NImre Deak <imre.deak@intel.com>
(cherry picked from commit 135dc79e)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

During system suspend we need to first disable power wells then
unitialize the display core. In case power well support is disabled we
did this in the wrong order, so fix this up.

Fixes: d314cd43 ("drm/i915: fix handling of the disable_power_well module option")
CC: stable@vger.kernel.org
CC: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NPatrik Jakobsson <patrik.jakobsson@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1456778945-5411-1-git-send-email-imre.deak@intel.com
(cherry picked from commit 2622d79b)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

commit 09731280
Author: Imre Deak <imre.deak@intel.com>
Date:   Wed Feb 17 14:17:42 2016 +0200

    drm/i915: Add helper to get a display power ref if it was already enabled

left the rpm wakelock assertions unbalanced if CONFIG_PM was disabled as
intel_runtime_pm_get_if_in_use() would return true without incrementing
the local bookkeeping required for the assertions.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
CC: Mika Kuoppala <mika.kuoppala@intel.com>
CC: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
CC: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Given that the intel_lr_context_pin cannot succeed without the object,
we cannot reach intel_lr_context_unpin() without first allocating that
object - so we can remove the redundant test.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1456485751-15213-1-git-send-email-tvrtko.ursulin@linux.intel.com

The multiple levels of indirect do nothing but hinder the compiler and
the pointer chasing turns to be quite painful but painless to fix.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NDave Gordon <david.s.gordon@intel.com>
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1456484600-11477-1-git-send-email-tvrtko.ursulin@linux.intel.com

Elsewhere we have adopted the convention of using '_link' to denote
elements in the list (and '_list' for the actual list_head itself), and
that the name should indicate which list the link belongs to (and
preferrably not just where the link is being stored).

s/vma_link/obj_link/ (we iterate over obj->vma_list)
s/mm_list/vm_link/ (we iterate over vm->[in]active_list)
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>

commit 09731280
Author: Imre Deak <imre.deak@intel.com>
Date:   Wed Feb 17 14:17:42 2016 +0200

    drm/i915: Add helper to get a display power ref if it was already enabled

left the rpm wakelock assertions unbalanced if CONFIG_PM was disabled as
intel_runtime_pm_get_if_in_use() would return true without incrementing
the local bookkeeping required for the assertions.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
CC: Mika Kuoppala <mika.kuoppala@intel.com>
CC: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
CC: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1456434628-22574-1-git-send-email-chris@chris-wilson.co.ukReviewed-by: NImre Deak <imre.deak@intel.com>

The driver should only set the "RS context enable" bit in the context
image if we plan to use the resource streamer.
Reviewed-by: NArun Siluvery <arun.siluvery@linux.intel.com>
Signed-off-by: NMichel Thierry <michel.thierry@intel.com>
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1456393738-35608-1-git-send-email-michel.thierry@intel.com

The cache line offset for the Indirect CS context (0x21C8) varies from gen
to gen.

v2: Move it into a function (Arun), use MISSING_CASE (Chris)
v3: Rebased (catched by ci bat)

Cc: Arun Siluvery <arun.siluvery@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NArun Siluvery <arun.siluvery@linux.intel.com>
Signed-off-by: NMichel Thierry <michel.thierry@intel.com>
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1456223509-6454-1-git-send-email-michel.thierry@intel.com

Commit 791a32be ("drm/i915: Drop intel_update_sprite_watermarks")
removes the use of this variable, but forgot to remove it.
Reviewed-by: NMatt Roper <matthew.d.roper@intel.com>
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455108583-29227-5-git-send-email-maarten.lankhorst@linux.intel.com

Currently we perform our own wait in post_plane_update,
but the atomic core performs another one in wait_for_vblanks.
This means that 2 vblanks are done when a fb is changed,
which is a bit overkill.

Merge them by creating a helper function that takes a crtc mask
for the planes to wait on.

The broadwell vblank workaround may look gone entirely but this is
not the case. pipe_config->wm_changed is set to true
when any plane is turned on, which forces a vblank wait.

Changes since v1:
- Removing the double vblank wait on broadwell moved to its own commit.
Changes since v2:
- Move out POWER_DOMAIN_MODESET handling to its own commit.
Changes since v3:
- Do not wait for vblank on legacy cursor updates. (Ville)
- Move broadwell vblank workaround comment to page_flip_finished. (Ville)
Changes since v4:
- Compile fix, legacy_cursor_flip -> *_update.
Changes since v5:
- Kill brackets.
- Add WARN_ON when wait_for_vblanks fails.
- Remove extra newlines.
- Split the checks whether vblank is needed to a separate function,
  with comments why a vblank is needed.
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/56CD84DA.5030507@linux.intel.comReviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>

Right now there's separate power domain handling for update_pipe and
modesets. Unify this and only grab POWER_DOMAIN_MODESET once.
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455108583-29227-3-git-send-email-maarten.lankhorst@linux.intel.comReviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>

Use our newly created encoder_mask to iterate over the encoders.
This makes it possible to get the crtc power domains from the
crtc_state at any time, without any locks or having to look at
the legacy state.
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455108583-29227-2-git-send-email-maarten.lankhorst@linux.intel.comReviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>

for_each_pipe_masked() can be used to iterate over the pipes
included in the user provided pipe mask. Removes a few lines of
duplicated code.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455907651-16397-2-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NImre Deak <imre.deak@intel.com>

Starting from BDW the DE_PIPE interrupts for pipe B and C belong to the
relevant display power well. So we should make sure we've finished
processing them before turning off the power well.

The pipe interrupts shouldn't really happen at this point anymore since
we've already shut down the planes/pipes/whatnot, but being a bit
paranoid shouldn't hurt.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455907651-16397-1-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NImre Deak <imre.deak@intel.com>

After we've told the irq code we don't want to handle display irqs
anymore, we must make sure any display irq handling already
kicked off has finished before we actually turn off the power well.

I wouldn't expect PIPESTAT based interrupts to occur anymore since
vblanks/page flips/gmbus/etc should all be quiescent at this point.
But at least hotplug interrupts could still occur. Hotplug
interrupts may also kick off the workqueue based hotplug processing,
but that code should take the required power domain references
itself, so there shouldn't be any need to synchronize with the
hotplug processing from the power well code.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455900112-15387-1-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NImre Deak <imre.deak@intel.com>

PIPESTAT registers live in the display power well on VLV/CHV, so we
shouldn't access them when things are powered down. Let's check
whether the display interrupts are on or off before accessing the
PIPESTAT registers.

Another option would be to read the PIPESTAT registers only when
the IIR register indicates that there's a pending pipe event. But
that would mean we might miss even more underrun reports than we
do now, because the underrun status bit lives in PIPESTAT but doesn't
actually generate an interrupt.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=93738
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455825266-24686-1-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NImre Deak <imre.deak@intel.com>

It has been observed that sometimes disabling the dc6 fails
and dc6 state pops back up, brief moment after disabling. This
has to be dmc save/restore timing issue or other bug in the
way dc states are handled.

Try to work around this issue as we don't have firmware fix
yet available. Verify that the value we wrote for the dmc sticks,
and also enforce it by rewriting it, if it didn't.

v2: Zero rereads on rewrite for extra paranoia (Imre)

Testcase: kms_flip/basic-flip-vs-dpms
References: https://bugs.freedesktop.org/show_bug.cgi?id=93768
Cc: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455811089-27884-1-git-send-email-mika.kuoppala@intel.com
(cherry picked from commit 779cb5d3)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

The DMC can incorrectly run off and allow DC states on it's own. We
don't know the root-cause for this yet but this patch makes it more
visible.
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NPatrik Jakobsson <patrik.jakobsson@linux.intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455808874-22089-2-git-send-email-mika.kuoppala@intel.com
(cherry picked from commit 832dba88)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

The assumption when adding the intel_display_power_is_enabled() checks
was that if it returns success the power can't be turned off afterwards
during the HW access, which is guaranteed by modeset locks. This isn't
always true, so make sure we hold a dedicated reference for the time of
the access.
Spotted-by: NMika Kuoppala <mika.kuoppala@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=93441
CC: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455719489-3008-1-git-send-email-imre.deak@intel.com
(cherry picked from commit 4d800030)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

The assumption when adding the intel_display_power_is_enabled() checks
was that if it returns success the power can't be turned off afterwards
during the HW access, which is guaranteed by modeset locks. This isn't
always true, so make sure we hold a dedicated reference for the time of
the access.
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1455296121-4742-13-git-send-email-imre.deak@intel.com
(cherry picked from commit ecb24482)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

The assumption when adding the intel_display_power_is_enabled() checks
was that if it returns success the power can't be turned off afterwards
during the HW access, which is guaranteed by modeset locks. This isn't
always true, so make sure we hold a dedicated reference for the time of
the access.
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1455296121-4742-12-git-send-email-imre.deak@intel.com
(cherry picked from commit 5b092174)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

The assumption when adding the intel_display_power_is_enabled() checks
was that if it returns success the power can't be turned off afterwards
during the HW access, which is guaranteed by modeset locks. This isn't
always true, so make sure we hold a dedicated reference for the time of
the access.
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1455296121-4742-11-git-send-email-imre.deak@intel.com
(cherry picked from commit 3f3f42b8)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

The assumption when adding the intel_display_power_is_enabled() checks
was that if it returns success the power can't be turned off afterwards
during the HW access, which is guaranteed by modeset locks. This isn't
always true, so make sure we hold a dedicated reference for the time of
the access.
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1455296121-4742-10-git-send-email-imre.deak@intel.com
(cherry picked from commit 6fa9a5ec)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

The assumption when adding the intel_display_power_is_enabled() checks
was that if it returns success the power can't be turned off afterwards
during the HW access, which is guaranteed by modeset locks. This isn't
always true, so make sure we hold a dedicated reference for the time of
the access.

While at it also add the missing reference around the HW access in
i915_interrupt_info().

v2:
- update the commit message mentioning that this also fixes the
  HW access in the interrupt info debugfs entry (Daniel)
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1455296121-4742-9-git-send-email-imre.deak@intel.com
(cherry picked from commit e129649b)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

The assumption when adding the intel_display_power_is_enabled() checks
was that if it returns success the power can't be turned off afterwards
during the HW access, which is guaranteed by modeset locks. This isn't
always true, so make sure we hold a dedicated reference for the time of
the access.

CC: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1455296121-4742-8-git-send-email-imre.deak@intel.com
(cherry picked from commit e27daab4)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

The assumption when adding the intel_display_power_is_enabled() checks
was that if it returns success the power can't be turned off afterwards
during the HW access, which is guaranteed by modeset locks. This isn't
always true, so make sure we hold a dedicated reference for the time of
the access.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=93439
CC: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1455296121-4742-7-git-send-email-imre.deak@intel.com
(cherry picked from commit 1c8fdda1)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

The assumption when adding the intel_display_power_is_enabled() checks
was that if it returns success the power can't be turned off afterwards
during the HW access, which is guaranteed by modeset locks. This isn't
always true, so make sure we hold a dedicated reference for the time of
the access.
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1455296121-4742-6-git-send-email-imre.deak@intel.com
(cherry picked from commit 4feed0eb)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

The assumption when adding the intel_display_power_is_enabled() checks
was that if it returns success the power can't be turned off afterwards
during the HW access, which is guaranteed by modeset locks. This isn't
always true, so make sure we hold a dedicated reference for the time of
the access.
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1455296121-4742-5-git-send-email-imre.deak@intel.com
(cherry picked from commit 6392f847)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

The assumption when adding the intel_display_power_is_enabled() checks
was that if it returns success the power can't be turned off afterwards
during the HW access, which is guaranteed by modeset locks. This isn't
always true, so make sure we hold a dedicated reference for the time of
the access.
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455296121-4742-4-git-send-email-imre.deak@intel.com
(cherry picked from commit 12fda387)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

The assumption when adding the intel_display_power_is_enabled() checks
was that if it returns success the power can't be turned off afterwards
during the HW access, which is guaranteed by modeset locks. This isn't
always true, so make sure we hold a dedicated reference for the time of
the access.
Signed-off-by: NImre Deak <imre.deak@intel.com>
Revieved-by: NMika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455296121-4742-3-git-send-email-imre.deak@intel.com
(cherry picked from commit 1729050e)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

We have many places in the code where we check if a given display power
domain is enabled and if so access registers backed by this power
domain. We assumed that some modeset lock will prevent the power
reference from vanishing in the middle of the HW access, but this
assumption doesn't always hold. In such cases we get either the wakeref
not held, or an unclaimed register access error message. To fix this in
a future-proof way that's independent of other locks wrap any such
access with a get_ref_if_enabled()/put_ref() pair.

Kudos to Ville and Joonas for the ideas of this new interface.

v2:
- init the power_domains ptr when declaring it everywhere (Joonas)
v3:
- don't report the device to be powered if runtime PM is disabled

CC: Mika Kuoppala <mika.kuoppala@intel.com>
CC: Chris Wilson <chris@chris-wilson.co.uk>
CC: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
CC: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455711462-7442-1-git-send-email-imre.deak@intel.com
(cherry picked from commit 09731280)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>