On platforms with shared interrupt enable bits (which are shared even
with the pipe CRC logic) there's some tricky corner cases. Add
information to make debugging those easier.
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

All drm_fb_helper_restore_fbdev_mode() call sites, save one, do the same
locking.  Simplify this into drm_fb_helper_restore_fbdev_mode_unlocked().
Signed-off-by: NRob Clark <robdclark@gmail.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDave Airlie <airlied@redhat.com>

For atomic, it will be quite necessary to not need to care so much
about locking order.  And 'state' gives us a convenient place to stash a
ww_ctx for any sort of update that needs to grab multiple crtc locks.

Because we will want to eventually make locking even more fine grained
(giving locks to planes, connectors, etc), split out drm_modeset_lock
and drm_modeset_acquire_ctx to track acquired locks.

Atomic will use this to keep track of which locks have been acquired
in a transaction.

v1: original
v2: remove a few things not needed until atomic, for now
v3: update for v3 of connection_mutex patch..
v4: squash in docbook
v5: doc tweaks/fixes
Signed-off-by: NRob Clark <robdclark@gmail.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDave Airlie <airlied@redhat.com>

This should avoid races between connector probing and HPD
irqs in the future, currently mode_config.mutex blocks this
possibility.
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDave Airlie <airlied@redhat.com>

After the split-out of crtc locks from the big mode_config.mutex
there's still two major areas it protects:
- Various connector probe states, like connector->status, EDID
  properties, probed mode lists and similar information.
- The links from connector->encoder and encoder->crtc and other
  modeset-relevant connector state (e.g. properties which control the
  panel fitter).

The later is used by modeset operations. But they don't really care
about the former since it's allowed to e.g. enable a disconnected VGA
output or with a mode not in the probed list.

Thus far this hasn't been a problem, but for the atomic modeset
conversion Rob Clark needs to convert all modeset relevant locks into
w/w locks. This is required because the order of acquisition is
determined by how userspace supplies the atomic modeset data. This has
run into troubles in the detect path since the i915 load detect code
needs _both_ protections offered by the mode_config.mutex: It updates
probe state and it needs to change the modeset configuration to enable
the temporary load detect pipe.

The big deal here is that for the probe/detect users of this lock a
plain mutex fits best, but for atomic modesets we really want a w/w
mutex. To fix this lets split out a new connection_mutex lock for the
modeset relevant parts.

For simplicity I've decided to only add one additional lock for all
connector/encoder links and modeset configuration states. We have
piles of different modeset objects in addition to those (like bridges
or panels), so adding per-object locks would be much more effort.

Also, we're guaranteed (at least for now) to do a full modeset if we
need to acquire this lock. Which means that fine-grained locking is
fairly irrelevant compared to the amount of time the full modeset will
take.

I've done a full audit, and there's just a few things that justify
special focus:
- Locking in drm_sysfs.c is almost completely absent. We should
  sprinkle mode_config.connection_mutex over this file a bit, but
  since it already lacks mode_config.mutex this patch wont make the
  situation any worse. This is material for a follow-up patch.

- omap has a omap_framebuffer_flush function which walks the
  connector->encoder->crtc links and is called from many contexts.
  Some look like they don't acquire mode_config.mutex, so this is
  already racy. Again fixing this is material for a separate patch.

- The radeon hot_plug function to retrain DP links looks at
  connector->dpms. Currently this happens without any locking, so is
  already racy. I think radeon_hotplug_work_func should gain
  mutex_lock/unlock calls for the mode_config.connection_mutex.

- Same applies to i915's intel_dp_hot_plug. But again, this is already
  racy.

- i915 load_detect code needs to acquire this lock. Which means the
  w/w dance due to Rob's work will be nicely contained to _just_ this
  function.

I've added fixme comments everywhere where it looks suspicious but in
the sysfs code. After a quick irc discussion with Dave Airlie it
sounds like the lack of locking in there is due to sysfs cleanup fun
at module unload.

v1: original (only compile tested)

v2: missing mutex_init(), etc (from Rob Clark)

v3: i915 needs more care in the conversion:
- Protect the edp pp logic with the connection_mutex.
- Use connection_mutex in the backlight code due to
  get_pipe_from_connector.
- Use drm_modeset_lock_all in suspend/resume paths.
- Update lock checks in the overlay code.

Cc: Alex Deucher <alexdeucher@gmail.com>
Cc: Rob Clark <robdclark@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: NRob Clark <robdclark@gmail.com>

Generated using semantic patches:

@@
expression E;
@@

- drm_get_encoder_name(&E)
+ E.name

@@
expression E;
@@

- drm_get_encoder_name(E)
+ E->name

v2: Turn drm_get_encoder_name(&E) into E.name instead of &(E)->name.
Acked-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Generated using semantic patches:

@@
expression E;
@@

- drm_get_connector_name(&E)
+ E.name

@@
expression E;
@@

- drm_get_connector_name(E)
+ E->name

v2: Turn drm_get_connector_name(&E) into E.name instead of &(E)->name.
Acked-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

It's barely alive now anyway, so give it the "coup de grâce".
Signed-off-by: NOscar Mateo <oscar.mateo@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Up until now, contexts had one (and only one) backing object that was
used by the hardware to save/restore render ring contexts (via the
MI_SET_CONTEXT command). Other rings did not have or need this, so
our i915_hw_context struct had a 1:1 relationship with a a real HW
context.

With Logical Ring Contexts and Execlists, this is not possible anymore:
all rings need a backing object, and it cannot be reused. To prepare
for that, rename our contexts to the more generic term intel_context.

No functional changes.
Signed-off-by: NOscar Mateo <oscar.mateo@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Manual cleanup after the previous Coccinelle script.

Yes, I could write another Coccinelle script to do this but I
don't want labor-replacing robots making an honest programmer's
work obsolete (also, I'm lazy).
Signed-off-by: NOscar Mateo <oscar.mateo@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This refactoring has been performed using the following Coccinelle
semantic script:

    @@
    struct intel_engine_cs r;
    @@
    (
    - (r).obj
    + r.buffer->obj
    |
    - (r).virtual_start
    + r.buffer->virtual_start
    |
    - (r).head
    + r.buffer->head
    |
    - (r).tail
    + r.buffer->tail
    |
    - (r).space
    + r.buffer->space
    |
    - (r).size
    + r.buffer->size
    |
    - (r).effective_size
    + r.buffer->effective_size
    |
    - (r).last_retired_head
    + r.buffer->last_retired_head
    )

    @@
    struct intel_engine_cs *r;
    @@
    (
    - (r)->obj
    + r->buffer->obj
    |
    - (r)->virtual_start
    + r->buffer->virtual_start
    |
    - (r)->head
    + r->buffer->head
    |
    - (r)->tail
    + r->buffer->tail
    |
    - (r)->space
    + r->buffer->space
    |
    - (r)->size
    + r->buffer->size
    |
    - (r)->effective_size
    + r->buffer->effective_size
    |
    - (r)->last_retired_head
    + r->buffer->last_retired_head
    )

    @@
    expression E;
    @@
    (
    - LP_RING(E)->obj
    + LP_RING(E)->buffer->obj
    |
    - LP_RING(E)->virtual_start
    + LP_RING(E)->buffer->virtual_start
    |
    - LP_RING(E)->head
    + LP_RING(E)->buffer->head
    |
    - LP_RING(E)->tail
    + LP_RING(E)->buffer->tail
    |
    - LP_RING(E)->space
    + LP_RING(E)->buffer->space
    |
    - LP_RING(E)->size
    + LP_RING(E)->buffer->size
    |
    - LP_RING(E)->effective_size
    + LP_RING(E)->buffer->effective_size
    |
    - LP_RING(E)->last_retired_head
    + LP_RING(E)->buffer->last_retired_head
    )

Note: On top of this this patch also removes the now unused ringbuffer
fields in intel_engine_cs.
Signed-off-by: NOscar Mateo <oscar.mateo@intel.com>
[danvet: Add note about fixup patch included here.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

As advanced by the previous patch, the ringbuffers and the engine
command streamers belong in different structs. This is so because,
while they used to be tightly coupled together, the new Logical
Ring Contexts (LRC for short) have a ringbuffer each.

In legacy code, we will use the buffer* pointer inside each ring
to get to the pertaining ringbuffer (the actual switch will be
done in the next patch). In the new Execlists code, this pointer
will be NULL and we will use instead the one inside the context
instead.
Signed-off-by: NOscar Mateo <oscar.mateo@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

In the upcoming patches we plan to break the correlation between
engine command streamers (a.k.a. rings) and ringbuffers, so it
makes sense to refactor the code and make the change obvious.

No functional changes.
Signed-off-by: NOscar Mateo <oscar.mateo@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Atm, we disable GT power saving during the end of the suspend sequence
in i915_save_state(). Doing the disabling at that point seems arbitrary.
One reason to disable it early though is to have a quiescent HW state
before we do anything else (for example save registers). So move the
disabling earlier, which also takes care canceling of the deferred RPS
enabling work done by intel_disable_gt_powersave().

Note that after the move we'll call intel_disable_gt_powersave() only
in case modeset is enabled, but that's anyway the only case where we
have it enabled in the first place.
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NRobert Beckett <robert.beckett@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

In

commit c6df39b5
Author: Imre Deak <imre.deak@intel.com>
Date:   Mon Apr 14 20:24:29 2014 +0300

    drm/i915: get a runtime PM ref for the deferred GT powersave enabling

I added an RPM get-ref when enabling RPS from a deferred work, but forgot
to add the corresponding put-ref when canceling the work. This may leave
RPM disabled.

Note that the race is real since we run the rps enabling with a
delayed work item after resume, so leaves enough time (in contrived
examples) to fit a quick autoresum in.
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NRobert Beckett <robert.beckett@intel.com>
Testecase: igt/pm_rpm/system-suspend
[danvet: Mention testcase and add note.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Currently user space can access GEM buffers mapped to GTT through
existing mappings concurrently while the platform specific suspend
handlers are running. Since these handlers may change the HW state in a
way that would break such accesses, remove the mappings before calling
the handlers. Spotted by Ville.

Also Chris pointed out that the lists that i915_gem_release_all_mmaps()
walks through need dev->struct_mutex, so take this lock. There is a
potential deadlock against a concurrent RPM resume, resolve this by
aborting and rescheduling the suspend (Daniel).

v2:
- take struct_mutex around i915_gem_release_all_mmaps() (Chris, Daniel)
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NRobert Beckett <robert.beckett@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Apparently we need to disable VCP unit clock gating around media reset
on g4x.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

On gen2 the scanline counter behaves a bit differently from the
later generations. Instead of adding one to the raw scanline
counter value, we must subtract one.

On HSW/BDW the scanline counter requires a +2 adjustment on HDMI
outputs. DP outputs on the on the other require the typical +1
adjustment.

As the fixup we must apply to the hardware scanline counter
depends on several factors, compute the desired offset at modeset
time and tuck it away for when it's needed.

v2: Clarify HSW+ situation
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: "Akash Goel <akash.goels@gmail.com>"
Reviewed-by: "Sourab Gupta <sourabgupta@gmail.com>"
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=78997Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The docs are a bit lacking when it comes to describing when certain
timing related events occur in the hardware. Draw a picture which
tries to capture the most important ones.

v2: Clarify a few details (Imre)
v3: Add HSW+ HDMI scanline counter numbers
Acked-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NAkash Goel <akash.goels@gmail.com>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: "Sourab Gupta <sourabgupta@gmail.com>"
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Currently the logic to fix up the frame counter on gen3/4 assumes that
start of vblank occurs at vblank_start*htotal pixels, when in fact
it occurs htotal-hsync_start pixels earlier. Apply the appropriate
adjustment to make the frame counter more accurate.

Also fix the vblank start position for interlaced display modes.
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: "Akash Goel <akash.goels@gmail.com>"
Reviewed-by: "Sourab Gupta <sourabgupta@gmail.com>"
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

In interlaced modes, the pixel counter counts all pixels,
so one field will have htotal more pixels. In order to avoid
the reported position from jumping backwards when the pixel
counter is beyond the length of the shorter field, just
clamp the position the length of the shorter field. This
matches how the scanline counter based position works since
the scanline counter doesn't count the two half lines.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: "Akash Goel <akash.goels@gmail.com>"
Reviewed-by: "Sourab Gupta <sourabgupta@gmail.com>"
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Daniel keeps on ramping up the warning level of the DRM and our display
core to make it complain whenever the locking rules are not followed.
This caught

commit 24576d23
Author: Jesse Barnes <jbarnes@virtuousgeek.org>
Date:   Tue Mar 26 09:25:45 2013 -0700

    drm/i915: enable VT switchless resume v3

introducing an unlocked access to the CRTC whilst disabling it for
suspend.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=78114Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Before purging our pages (as opposed to copying back the contents from
the GPU), make sure that there is not an exposed CPU mmapping through
which the user can inspect the results.

Regression from

commit 5537252b
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Tue Mar 25 13:23:06 2014 +0000

    drm/i915: Invalidate our pages under memory pressure

Testcase: igt/gem_mmap/new-object
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=79005Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Tested-by: NGuo Jinxian <jinxianx.guo@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We have to write to the primary plane base address registrer when we
enable/disable the primary plane in response to sprite coverage. Those
writes will cause the flip counter to increment which could interfere
with the detection of CS flip completion. We could end up completing
CS flips before the CS has even executed the commands from the ring.

To avoid such issues, wait for CS flips to finish before we toggle the
primary plane on/off.

v2: Rebased due to atomic sprite update changes

Testcase: igt/kms_mmio_vs_cs_flip/setplane_vs_cs_flip
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by Rodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

With the current code, we unconditionally touch
HSW_AUD_PIN_ELD_CP_VLD, which means we can touch it when the power
well is off, and that will trigger an "Unclaimed register" message.

Just adding the intel_crtc->config.has_audio should already avoid the
unclaimed register messsages, but since we actually need the power
well to make the Audio code work, it makes sense to also grab the
audio power domain reference, and release it when it's not needed
anymore.

I used IGT's pm_rpm to reproduce this bug, but it can probably be
reproduced on other tests that do modesets. I'm using a machine with
eDP+HDMI connected.

Regression introduced by:

commit acfa75b0
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Thu Apr 24 23:54:51 2014 +0200
    drm/i915: Simplify audio handling on DDI ports

Credits to Daniel for suggesting this implementation.

Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Because this will trigger "Unclaimed register" messages. All I need to
reproduce this problem is to boot my HSW machine with eDP+HDMI
connected.

Regression introduced by:

commit 9ed109a7
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Thu Apr 24 23:54:52 2014 +0200
    drm/i915: Track has_audio in the pipe config

Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Adding stuff at the bottom is really no how this should be done, since
that's the place for ums/dri dungeons.

This was added in

commit a8ebba75
Author: Zhao Yakui <yakui.zhao@intel.com>
Date:   Thu Apr 17 10:37:40 2014 +0800

    drm/i915: Use the coarse ping-pong mechanism based on drm fd to dispatch the BSD command on BDW GT3

Also add a note to prevent this from happening again - people really
should be less lazy and take more time to look for a good home of
their new driver-global state.

Cc: Imre Deak <imre.deak@intel.com>
Cc: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Gen2 reports FIFO underruns whenever no planes are enabled on the pipe.
So in order to avoid false positives we must enable the FIFO underrun
reporting only when at least one plane is enabled on the pipe. For
now just move the underrun reporting enable/disable points to the
other side of the plane enable/disable point. That doesn't cover cases
when we turn off all the planes for the pipe but leave the pipe running
on purpose, but it's better than the current situation.

On gen4+ we can actually move the underrun reporting enable/disable to
the opposite ends of the crtc enable/disable hooks. I suppose in theory
we could leave the underrun reporting enabled all the time, except on
VLV where PIPESTAT stops working when the display power well is down.
If we ever get around to unifying the PIPESTAT irq handling for all
gmch platforms, we should still follow the VLV route for other platforms.
It would also micro-optimize the irq handler a bit since we could then
skip the PIPESTAT reads for all disabled pipes.

Gen3 is still a mystery, but for now I'm going to assume it behaves
like gen4+.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NThomas Wood <thomas.wood@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Checking whether the error interrupt was enabled or not isn't really
necessary when we check for uncleared FIFO underruns. If it was enabled
we'll race with the interrupt handler a bit, but that seems OK as we
still claim the interrupt.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NThomas Wood <thomas.wood@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

FIFO underruns don't generate interrupts on gmch platforms, so
if we want to know whether a modeset triggered FIFO underruns we
need to explicitly check for them.

As a modeset on one pipe could cause underruns on other pipes,
check for underruns on all pipes.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NThomas Wood <thomas.wood@intel.com>
[danvet: Fix up merge error, kudos to Ville for noticing it.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

FIFO underruns don't generate an interrupt on gmch platforms, so we
should check whether there were any that we failed to notice when
we're disabling FIFO underrun reporting.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NThomas Wood <thomas.wood@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Document the internal structure of the VLV display PHY a bit to help
people understand how the different register blocks relate to each
other.

v2: Add a bit more text
    Make it a DOC: comment, but leave the ascii art out since
    it would get mangled
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NChon Ming Lee <chon.ming.lee@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

for proper refcounting to take place as we use
i915_add_request() for it.

i915_add_request() also takes the context for the request
from ring->last_context so move the null state batch
submission after the ring context has been set.

v2: we need to check for correct ring now (Ville Syrjälä)
v3: no need to expose i915_gem_move_object_to_active (Chris Wilson)
v4: cargoculted vma/active/inactive error handling removed (Chris Wilson)

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

If a pipe is already active when we init/resume there might not be a
full modeset afterwards so drm_vblank_on() may not get called. In such
a case if someone is holding a vblank reference across a suspend/resume
cycle drm_vblank_get() called after resuming won't re-enable the vblank
interrupts.

So in order to make sure vblank interrupts get re-enabled post-resume,
call drm_vblank_on() in intel_sanitize_crtc() if the crtc is already
active.

v2: Also drm_vblank_off() if the pipe got disabled magically
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Testecase: igt/kms_flip/vblank-vs-suspend
Tested-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We don't have hardware based disable bits on gmch platforms, so need
to block spurious underrun reports in software. Which means that we
_must_ start out with fifo underrun reporting disabled everywhere.

This is in big contrast to ilk/hsw/cpt where there's only _one_
disable bit for all platforms and hence we must allow underrun
reporting on disabled pipes. Otherwise nothing really works,
especially the CRC support since that's key'ed off the same irq
disable bit.

This allows us to ditch the fifo underrun reporting hack from the vlv
runtime pm code and unexport the internal function from i915_irq.c
again. Yay!

v2: Keep the display irq disabling, spotted by Imre.

Cc: Imre Deak <imre.deak@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Now that we unconditionally dtrt when disabling/enabling crtcs we
don't need any hacks any longer to keep the vblank logic sane when
all the registers go poof. So let's rip it all out.

This essentially undoes

commit 9dbd8feb
Author: Paulo Zanoni <paulo.r.zanoni@intel.com>
Date:   Tue Jul 23 10:48:11 2013 -0300

    drm/i915: update last_vblank when disabling the power well

Apparently igt/kms_flip is already powerful enough to exercise this
properly, yay! See the reference regression report for details.

v2: Update testcase name

References: https://bugs.freedesktop.org/show_bug.cgi?id=66808
Testcase: igt/kms_flip/vblank-vs-*-rpm
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Only the low-level irq handling functions still use integer crtc
indices with this. But fixing that will require a lot more sugery
and some good ideas for backwards compat with old ums userspace.
Both in drivers and in the drm core.
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Originally these functions have been for user modesetting drivers to
ensure vblank processing doesn't fall over completely around modeset
changes. This has been carried over ever since then.

Now that Ville cleaned our vblank handling with an explicit
drm_vblank_off/on braket when disabling/enabling crtcs. So this seems
to be unnecessary now. The most important side effect was that due to
the delayed vblank disabling we have been pretty much guaranteed to
receive a vblank interrupt soonish after a crtc was enabled.

Note that our vblank handling across modeset is still fairly decent
fubar - we don't actually handle vblank counter all to well.
drm_update_vblank_count will make sure that the frame counter always
rolls forward, but userspace isn't really all to ready to cope with
the big jumps this causes.

This isn't a big mostly because the hardware retains the frame
counter. But with runtime pm and also across suspend/resume we fall
over.

Fixing this is a lot more involved and also needs som i-g-ts. So
material for another patch series.
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

All of the .queue_flip() callbacks duplicate the same code to pin the
buffers and calculate the gtt_offset. Move that code to
intel_crtc_page_flip(). In order to do that we must also move the ring
selection logic there.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Now that we've plugged the mmio vs. ring flip race, we shouldn't need
these vblank waits in the modeset codepaths anymore. So get rid of
them.

v2: gen2 needs to wait for planes to turn off before disabling pipe
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>