Instead of repopulatin the rotation_info struct for the fb every time
we try to use the fb, we can just populate it once when creating the fb,
and later we can just copy the pre-populate struct into the gtt_view.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1455569699-27905-10-git-send-email-ville.syrjala@linux.intel.com

rotate_pages() checks to see if it got called with a NULL sg, and then
goes to extract it from sg->sgl. It always gets called with a NULL sg
for the first plane, so moving the initial 'sg=st->sgl' assignment out
into intel_rotate_fb_obj_pages() seems less special-casey.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1455569699-27905-9-git-send-email-ville.syrjala@linux.intel.com

Throw out a bunch of unnecessary stuff from struct intel_rotation_info,
and pull most of the remaining stuff to live under an array of
per-color plane sub-structures.

What still remains outside the sub-structure will be reorgranized later
as well, but that requires more work elsewhere so leave it be for now.

v2: Split the vma size == luma+chroma size fix to prep patch (Daniel)
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> (v1)
Link: http://patchwork.freedesktop.org/patch/msgid/1455569699-27905-8-git-send-email-ville.syrjala@linux.intel.com

intel_compute_page_offsets() gets passed a bunch of the framebuffer
metadate sepearately. Just pass the framebuffer itself to make life
simpler for the caller, and make it less likely they would make a
mistake in the order of the arguments (as most as just unsigned ints and
such).

We still pass the pitch explicitly since for 90/270 degree rotation
the caller has to pass in the right thing.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1455569699-27905-7-git-send-email-ville.syrjala@linux.intel.com

intel_pin_and_fence_fb_obj() only needs the framebuffer, and the desird
rotation (to find the right GTT view for it), so no need to pass all
kinds of plane stuff.

The main motivation is to get rid of the uggy NULL plane_state handling
due to fbdev.

v2: Add a note why I really want this
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Grumpily-Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1455569699-27905-6-git-send-email-ville.syrjala@linux.intel.com

SKL+ needs >4K alignment for tiled surfaces, so make
intel_compute_page_offset() handle it.

The way we do it is first we compute the closest tile boundary
as before, and then figure out how many tiles we need to go
to reach the desired alignment. The difference in the offset
is then added into the x/y offsets.

v2: Be less confusing wrt. units (pixels vs. bytes) (Daniel)
v3: Use u32 for offsets
    Have intel_adjust_tile_offset() return the new offset (will be
    useful later)
    Add an offset_aligned variable (Daniel)
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455569699-27905-5-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The page aligned surface address calculation needs to know which way
things are rotated. The contract now says that the caller must pass the
rotate x/y coordinates, as well as the tile_height aligned stride in
the tile_height direction. This will make it fairly simple to deal with
90/270 degree rotation on SKL+ where we have to deal with the rotated
view into the GTT.

v2: Pass rotation instead of bool even thoughwe only care about 0/180 vs. 90/270
v3: Introduce intel_tile_dims(), and don't mix up different units so much
v4: Unconfuse bytes vs. pixels even more
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455569699-27905-4-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Make if clear whether we're talking tile widths in bytes or in pixels.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455569699-27905-3-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The size of the rotated ggtt mapping ought to include the size of the
chroma plane as well. Not a huge deal since we don't expose NV12 (or any
pother planar format for that matter) yet.

Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Fixes: 89e3e142 ("drm/i915: Support NV12 in rotated GGTT mapping")
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455569699-27905-2-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>

Not all platforms set this callback, so NULL check it before calling it.

v2:
- Call intel_update_watermarks() on HSW+ where the callback is not set.
  (Matt)

CC: Matt Roper <matthew.d.roper@intel.com>
Fixes: commit ed4a6a7c ("drm/i915: Add two-stage ILK-style watermark programming (v11)")
Signed-off-by: NImre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1456776633-3401-1-git-send-email-imre.deak@intel.comReviewed-by: NMatt Roper <matthew.d.roper@intel.com>

Assorted changes in the areas of code cleanup, reduction of
invariant conditional in the interrupt handler and lock
contention and MMIO access optimisation.

 * Remove needless initialization.
 * Improve cache locality by reorganizing code and/or using
   branch hints to keep unexpected or error conditions out
   of line.
 * Favor busy submit path vs. empty queue.
 * Less branching in hot-paths.

v2:

 * Avoid mmio reads when possible. (Chris Wilson)
 * Use natural integer size for csb indices.
 * Remove useless return value from execlists_update_context.
 * Extract 32-bit ppgtt PDPs update so it is out of line and
   shared with two callers.
 * Grab forcewake across all mmio operations to ease the
   load on uncore lock and use chepear mmio ops.

v3:

 * Removed some more pointless u8 data types.
 * Removed unused return from execlists_context_queue.
 * Commit message updates.

v4:
 * Unclumsify the unqueue if statement. (Chris Wilson)
 * Hide forcewake from the queuing function. (Chris Wilson)

Version 3 now makes the irq handling code path ~20% smaller on
48-bit PPGTT hardware, and a little bit less elsewhere. Hot
paths are mostly in-line now and hammering on the uncore
spinlock is greatly reduced together with mmio traffic to an
extent.

Benchmarking with "gem_latency -n 100" (keep submitting
batches with 100 nop instruction) shows approximately 4% higher
throughput, 2% less CPU time and 22% smaller latencies. This was
on a big-core while small-cores could benefit even more.

Most likely reason for the improvements are the MMIO
optimization and uncore lock traffic reduction.

One odd result is with "gem_latency -n 0" (dispatching empty
batches) which shows 5% more throughput, 8% less CPU time,
25% better producer and consumer latencies, but 15% higher
dispatch latency which is yet unexplained.
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1456505912-22286-1-git-send-email-tvrtko.ursulin@linux.intel.com

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>

79e53945 ("DRM: i915: add mode setting
support") added those variables but never used them.
Signed-off-by: NEric Engestrom <eric.engestrom@imgtec.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1456763047-28828-2-git-send-email-eric.engestrom@imgtec.com

ae80152d ("drm/i915: Rewrite VLV/CHV
watermark code") removed everything that would have used those vars.
Signed-off-by: NEric Engestrom <eric.engestrom@imgtec.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1456763047-28828-1-git-send-email-eric.engestrom@imgtec.com

In addition to calculating final watermarks, let's also pre-calculate a
set of intermediate watermark values at atomic check time.  These
intermediate watermarks are a combination of the watermarks for the old
state and the new state; they should satisfy the requirements of both
states which means they can be programmed immediately when we commit the
atomic state (without waiting for a vblank).  Once the vblank does
happen, we can then re-program watermarks to the more optimal final
value.

v2: Significant rebasing/rewriting.

v3:
 - Move 'need_postvbl_update' flag to CRTC state (Daniel)
 - Don't forget to check intermediate watermark values for validity
   (Maarten)
 - Don't due async watermark optimization; just do it at the end of the
   atomic transaction, after waiting for vblanks.  We do want it to be
   async eventually, but adding that now will cause more trouble for
   Maarten's in-progress work.  (Maarten)
 - Don't allocate space in crtc_state for intermediate watermarks on
   platforms that don't need it (gen9+).
 - Move WaCxSRDisabledForSpriteScaling:ivb into intel_begin_crtc_commit
   now that ilk_update_wm is gone.

v4:
 - Add a wm_mutex to cover updates to intel_crtc->active and the
   need_postvbl_update flag.  Since we don't have async yet it isn't
   terribly important yet, but might as well add it now.
 - Change interface to program watermarks.  Platforms will now expose
   .initial_watermarks() and .optimize_watermarks() functions to do
   watermark programming.  These should lock wm_mutex, copy the
   appropriate state values into intel_crtc->active, and then call
   the internal program watermarks function.

v5:
 - Skip intermediate watermark calculation/check during initial hardware
   readout since we don't trust the existing HW values (and don't have
   valid values of our own yet).
 - Don't try to call .optimize_watermarks() on platforms that don't have
   atomic watermarks yet.  (Maarten)

v6:
 - Rebase

v7:
 - Further rebase

v8:
 - A few minor indentation and line length fixes

v9:
 - Yet another rebase since Maarten's patches reworked a bunch of the
   code (wm_pre, wm_post, etc.) that this was previously based on.

v10:
 - Move wm_mutex to dev_priv to protect against racing commits against
   disjoint CRTC sets. (Maarten)
 - Drop unnecessary clearing of cstate->wm.need_postvbl_update (Maarten)

v11:
 - Now that we've moved to atomic watermark updates, make sure we call
   the proper function to program watermarks in
   {ironlake,haswell}_crtc_enable(); the failure to do so on the
   previous patch iteration led to us not actually programming the
   watermarks before turning on the CRTC, which was the cause of the
   underruns that the CI system was seeing.
 - Fix inverted logic for determining when to optimize watermarks.  We
   were needlessly optimizing when the intermediate/optimal values were
   the same (harmless), but not actually optimizing when they differed
   (also harmless, but wasteful from a power/bandwidth perspective).

Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NMatt Roper <matthew.d.roper@intel.com>
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1456276813-5689-1-git-send-email-matthew.d.roper@intel.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>

DMC debugmask bits should stick so no need to write them
everytime dc state is changed.

v2: Write after firmware has been successfully loaded (Ville)
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/1455808874-22089-5-git-send-email-mika.kuoppala@intel.com

Cores need to be included into the debug mask. We don't exactly
know what it does but the spec says it must be enabled. So obey.

v2: Cores should be only set for BXT (Imre, Art)

Cc: Imre Deak <imre.deak@intel.com>
Cc: Runyan, Arthur J <arthur.j.runyan@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/1455877564-5128-1-git-send-email-mika.kuoppala@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

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

These platforms should be fine now.

FBC can allow very significant power savings for screen-on idle
systems, but it is worth mentioning that a lot of people won't get
significant power savings by enabling this feature because they may
have something else preventing the system from getting into the
deepest sleep states. Examples may include a hungry wifi device or a
max_performance SATA link power management policy. You can check your
PC state residencies on the powertop "Idle stats" tab. I recommend
trying to run "sudo powertop --auto-tune" and then seeing if the
residencies improve.

Oh, and in case you - the person reading this commit message - found
this commit through git bisect, please do the following:
 - Check your dmesg and see if there are error messages mentioning
   underruns around the time your problem started happening.
 - Download intel-gpu-tools, compile it, and run:
   $ sudo ./tests/kms_frontbuffer_tracking --run-subtest '*fbc-*' 2>&1 | tee fbc.txt
   Then send us the fbc.txt file, especially if you get a failure.
   This will really maximize your chances of getting the bug fixed
   quickly.
 - Try to find a reliable way to reproduce the problem, and tell us.
 - Boot with drm.debug=0xe, reproduce the problem, then send us the
   dmesg file.

v2: Don't enable by default on SKL.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1455655643-2535-1-git-send-email-paulo.r.zanoni@intel.com

This is a manual revert of

commit 7a10dfa6
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Tue Apr 1 09:33:47 2014 +0200

    drm/i915: Add debug module option for VTd validation

as no users have appeared.
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455621493-6865-2-git-send-email-jani.nikula@intel.com

We've given write permissions to dynamically change some module
parameters through /sys/module/i915/parameters although they only
support setting on module load. Fix the permissions.
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455621493-6865-1-git-send-email-jani.nikula@intel.com

The bpp value which is used while calulating the txbyteclkhs values
should be wrt the pixel format value. Currently bpp is coming
from pipe config to calculate txbyteclkhs. Fix it in this patch.

V2: dsi_pixel_format_bpp is used to retrieve the bpp from pixel_format
	[Review: Jani]
Signed-off-by: NDeepak M <m.deepak@intel.com>
Signed-off-by: NYogesh Mohan Marimuthu <yogesh.mohan.marimuthu@intel.com>
Signed-off-by: NRamalingam C <ramalingam.c@intel.com>
Tested-by: Mika Kahola <mika.kahola@intel.com> # BYT
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455203007-10850-1-git-send-email-ramalingam.c@intel.com

DSP CLK_GATE registers are specific to BYT and CHT.
Avoid programming the same for BXT platform.

v2: Rebased on latest drm nightly branch.

v3: Fixed Jani's review comments
Signed-off-by: NUma Shankar <uma.shankar@intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455796166-13052-1-git-send-email-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