This reverts commit 2e5356da.

It is now redundant as it is already covered in below commit which introduced
the changes to reuse initialization of resources in resume/reset path.

commit e84fe803
Author: Nick Hoath <nicholas.hoath@intel.com>
Date:   Fri Sep 11 12:53:46 2015 +0100

    drm/i915: Split alloc from init for lrc

lrc_setup_hardware_status_page() in the same function gen8_init_common_ring()
takes care of this.

Cc: Nick Hoath <nicholas.hoath@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NArun Siluvery <arun.siluvery@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1447951664-9347-1-git-send-email-arun.siluvery@linux.intel.comSigned-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

intelfb_create() is called once on driver initialization. If it fails,
ifbdev->helper.fbdev, ifbdev->fb or ifbdev->fb->obj may be NULL.

Further up in the call stack, intel_fbdev_initial_config() calls
intel_fbdev_fini() to tear down the ifbdev on failure. This calls
intel_fbdev_destroy() which dereferences ifbdev->fb. Fix the ensuing
oops.

Also check in these functions if ifbdev is not NULL to avoid oops:

i915_gem_framebuffer_info() is called on access to debugfs file
"i915_gem_framebuffer" and dereferences ifbdev, ifbdev->helper.fb
and ifbdev->helper.fb->obj.

intel_connector_add_to_fbdev() / intel_connector_remove_from_fbdev()
are called when registering / unregistering an mst connector and
dereference ifbdev.

v3: Drop additional null pointer checks in intel_fbdev_set_suspend(),
    intel_fbdev_output_poll_changed() and intel_fbdev_restore_mode()
    since they already check if ifbdev is not NULL, which is sufficient
    now that intel_fbdev_fini() is called on initialization failure.
    (Requested by Daniel Vetter <daniel.vetter@ffwll.ch>)
Signed-off-by: NLukas Wunner <lukas@wunner.de>
Link: http://patchwork.freedesktop.org/patch/msgid/d05f0edf121264a9d0adb8ca713fd8cc4ae068bf.1447938059.git.lukas@wunner.deSigned-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The rotated view depends upon the rotation paramters, but thus far we
didn't bother checking for those. This seems to have been an issue
ever since this was introduce in

commit fe14d5f4
Author: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Date:   Wed Dec 10 17:27:58 2014 +0000

    drm/i915: Infrastructure for supporting different GGTT views per object

But userspace is allowed to reuse framebuffer backing storage with
different framebuffers with different pixel formats/stride/whatever.
And e.g. SNA indeed does this. Hence we must check for all the
paramters to match, not just that it's rotated.

v2: intel_plane_obj_offset also needs to construct the full view, to
avoid fallout since they don't fully match.

Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1444834266-12689-3-git-send-email-daniel.vetter@ffwll.chReviewed-by: NTvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We don't need 2 separate unions.

Note that this was done intentinoally

Author: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Date:   Wed May 6 14:35:38 2015 +0300

    drm/i915: Add a partial GGTT view type

on Tvrtko's request, but without a clear justification. Rotated views
are also not checking for matching paramters in i915_ggtt_view_equal,
which seems like a bug. But this patch here doesn't change that.

Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1444834266-12689-2-git-send-email-daniel.vetter@ffwll.chReviewed-by: NTvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

It can't fail and there's even a WARN_ON suggesting that if it would,
it would be a disaster.

Correct this to make things less confusing.

Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1444834266-12689-1-git-send-email-daniel.vetter@ffwll.chReviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

    Found by static analysis tool.
Signed-off-by: NNamrta Salonie <namrta.salonie@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

MISSING_CASE() would have been useful to track down a recent problem in
intel_display_port_aux_power_domain(), so add it there and a few related
helpers. This was also suggested by Ville in his review of the latest
DMC/DC changes, we forgot to address that.
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NPatrik Jakobsson <patrik.jakobsson@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1447855045-7109-2-git-send-email-imre.deak@intel.com

Due to the current sharing of the DDI encoder between DP and HDMI
connectors we can run the DP detection after the HDMI detection has
already set the shared encoder's type. For now solve this keeping the
current behavior and running the detection in this case too. For a proper
solution Ville suggested to split the encoder into an HDMI and DP one, that
can be done as a follow-up.

This issue triggers the WARN in intel_display_port_aux_power_domain() and
was introduced in:
commit 25f78f58
Author: Ville Syrjälä <ville.syrjala@linux.intel.com>
Date:   Mon Nov 16 15:01:04 2015 +0100

    drm/i915: Clean up AUX power domain handling

CC: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
CC: Ville Syrjälä <ville.syrjala@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/1447855045-7109-1-git-send-email-imre.deak@intel.com

Their logic is exactly the same: check if the digital port is connected
and then call intel_dp_detect_dpcd(). So just put that logic in their
only caller: intel_dp_detect().
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/1447859970-9546-2-git-send-email-ander.conselvan.de.oliveira@intel.com

That call was moved to intel_dp_detect() in

commit d410b56d
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Tue Sep 2 20:03:59 2014 +0100

    drm/i915/dp: Refactor common eDP lid detection

but it seem to have been resurrected in the following commit, probably
due to a wrong merge conflict resolution.

commit 2a592bec
Author: Dave Airlie <airlied@redhat.com>
Date:   Mon Sep 1 16:58:12 2014 +1000

    drm/i915: handle G45/GM45 pulse detection connected state.
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/1447859970-9546-1-git-send-email-ander.conselvan.de.oliveira@intel.com

On the commit 3301d409 ("drm/i915: PSR: Fix DP_PSR_NO_TRAIN_ON_EXIT logic")'
we already had identified that DP_PSR_NO_TRAIN_ON_EXIT
doesn't mean we shouldn't send TPS patterns, however we start sending the
minimal TP1 as possible and no TP2.

For most of the panels this is ok, but we found a reported case where
this is not true and panel keeps frozen without updating the screen for a while.

We could just get this case after patch "PSR: Don't Skip aux handshake on
DP_PSR_NO_TRAIN_ON_EXIT." is applied since that one fix the
hard freeze on this kind of panels.

Reference: https://bugs.freedesktop.org/show_bug.cgi?id=91436#c19

Cc: Ivan Mitev <ivan.mitev@gmail.com>
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NDurgadoss R <durgadoss.r@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Since the beginning there is a confusion on the meaning of this bit.

A previous patch had identified this already and fixed it partially:
'commit 3301d409 ("drm/i915: PSR: Fix DP_PSR_NO_TRAIN_ON_EXIT logic")

DP_PSR_NO_TRAIN_ON_EXIT means the source doesn't need to do the
training, but it doesn't tell to avoid TP patterns or to skip
aux handshake.

This patch fixes the hard freeze reported.

Reference: https://bugs.freedesktop.org/show_bug.cgi?id=91436
Reference: https://bugs.freedesktop.org/show_bug.cgi?id=91437

Cc: Ivan Mitev <ivan.mitev@gmail.com>
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NDurgadoss R <durgadoss.r@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

With 'commit 30886c5a ("drm/i915: VLV/CHV PSR: Increase wait delay
 time before active PSR.")' we fixed a blank screen when first
activation was happening immediately after PSR being enabled.
There we gave more time for idleness by increasing the delay
between re-activating sequences.

However, commit "drm/i915: Delay first PSR activation."
delay the first activation in a better way keeping a good PSR
residency. So, we can now reduce the delay on re-enable.
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NDurgadoss R <durgadoss.r@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

When debuging the frozen screen caused by HW tracking with low
power state I noticed that if we keep moving the mouse non stop
you will miss the screen updates for a while. At least
until we stop moving the mouse for a small time and move again.

The actual enabling should happen immediately after
Display Port enabling sequence finished with links trained and
everything enabled. However we face many issues when enabling PSR
right after a modeset.

On VLV/CHV we face blank screens on this scenario and on HSW+
we face a recoverable frozen screen, at least until next
exit-activate sequence.

Another workaround for the same issue here would be to increase
re-enable idle time from 100 to 500 as we did for VLV/CHV.
However this patch workaround this issue in a better
way since it doesn't reduce PSR residency and also
allow us to reduce the delay time between re-enables at least
on VLV/CHV.

This is also important to make the sysfs toggle working properly.
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NDurgadoss R <durgadoss.r@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Make I915_READ and I915_WRITE more type safe by wrapping the register
offset in a struct. This should eliminate most of the fumbles we've had
with misplaced parens.

This only takes care of normal mmio registers. We could extend the idea
to other register types and define each with its own struct. That way
you wouldn't be able to accidentally pass the wrong thing to a specific
register access function.

The gpio_reg setup is probably the ugliest thing left. But I figure I'd
just leave it for now, and wait for some divine inspiration to strike
before making it nice.

As for the generated code, it's actually a bit better sometimes. Eg.
looking at i915_irq_handler(), we can see the following change:
  lea    0x70024(%rdx,%rax,1),%r9d
  mov    $0x1,%edx
- movslq %r9d,%r9
- mov    %r9,%rsi
- mov    %r9,-0x58(%rbp)
- callq  *0xd8(%rbx)
+ mov    %r9d,%esi
+ mov    %r9d,-0x48(%rbp)
 callq  *0xd8(%rbx)

So previously gcc thought the register offset might be signed and
decided to sign extend it, just in case. The rest appears to be
mostly just minor shuffling of instructions.

v2: i915_mmio_reg_{offset,equal,valid}() helpers added
    s/_REG/_MMIO/ in the register defines
    mo more switch statements left to worry about
    ring_emit stuff got sorted in a prep patch
    cmd parser, lrc context and w/a batch buildup also in prep patch
    vgpu stuff cleaned up and moved to a prep patch
    all other unrelated changes split out
v3: Rebased due to BXT DSI/BLC, MOCS, etc.
v4: Rebased due to churn, s/i915_mmio_reg_t/i915_reg_t/
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1447853606-2751-1-git-send-email-ville.syrjala@linux.intel.com

Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446672017-24497-29-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NChris Wilson <chris@chris-wilson.co.uk>

Add 'u32 offset' to the uncore register access functions. For now
it's the same as 'reg', but once type safety gets added 'reg' will be
the type safe register variable and 'offset' the raw offset.

v2: s/uint32_t/u32/ (Chris)

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446839236-20035-1-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NChris Wilson <chris@chris-wilson.co.uk>

I need to add a new variable into GEN6_{READ,WRITE}_HEADER, but the vgpu
won't need it, so let's avoid an unused variable warning by splitting
the vgpu stuff to use its own macros.

Cc: Eddie Dong <eddie.dong@intel.com>
Cc: Jike Song <jike.song@intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Yu Zhang <yu.c.zhang@linux.intel.com>
Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Zhiyuan Lv <zhiyuan.lv@intel.com>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446672017-24497-26-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NZhiyuan Lv <zhiyuan.lv@intel.com>

We'll want to avoid performing arithmetic with register offsets, so
instead calculating the vgpu PDP as pdp0_lo+offset, make the PDPs
into an array. This way we can simply loop through them.

Cc: Eddie Dong <eddie.dong@intel.com>
Cc: Jike Song <jike.song@intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Yu Zhang <yu.c.zhang@linux.intel.com>
Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Zhiyuan Lv <zhiyuan.lv@intel.com>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446672017-24497-25-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NZhiyuan Lv <zhiyuan.lv@intel.com>

We set up a load of LRIs in the logical ring context. Wrap that stuff
in a macro to avoid typos with position of each reg/value pair in the
context. This also makes it easier to make the register defines type
safe.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446672017-24497-24-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NChris Wilson <chris@chris-wilson.co.uk>

The logical render context population has a bunch of raw ring register
offsets. Use the names we have for them, and in cases where we we don't,
give them names.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446672017-24497-23-git-send-email-ville.syrjala@linux.intel.comReviewed-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/1446672017-24497-22-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NChris Wilson <chris@chris-wilson.co.uk>

Add a helper for emitting register offsets (for LRI/SRM) into the w/a
batch buffer.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446672017-24497-21-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NChris Wilson <chris@chris-wilson.co.uk>

When register type safety happens, we can't just try to emit the
register itself to the ring. Instead we'll need to extract the
offset from it first. Add some convenience functions that will do
that.

v2: Convert MOCS setup too
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446672017-24497-20-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NChris Wilson <chris@chris-wilson.co.uk>

Add defines for the upper halves of the registers used by the cmd
parser. Getting rid of the arithmetic with the register offset
will help in making registers type safe.

v2: s/_HI/_UDW/ (Chris)
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1446839080-18732-1-git-send-email-ville.syrjala@linux.intel.com

Store the upper dword of the register offset in the whitelist as well.
This would allow it to read register where the two halves aren't sitting
right next to each other, and it'll make it easier to make register
access type safe.

While at it change the register offsets to u32 from u64. Our register
space isn't quite that big, yet :)

v2: Use ldw/udw as the suffixes, and add a note about
    64bit wide split regs (Chris)

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446839021-18599-1-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NChris Wilson <chris@chris-wilson.co.uk>

Use the RING_PSMI_CTL define insted of hand rolling the register offset.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446672017-24497-17-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NChris Wilson <chris@chris-wilson.co.uk>

v2: Use for_each_ring() (Chris)

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Francisco Jerez <currojerez@riseup.net>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446725633-6419-1-git-send-email-ville.syrjala@linux.intel.comReviewed-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/1446672017-24497-15-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NChris Wilson <chris@chris-wilson.co.uk>

Most of our register defines follow the convention that if there's a
need for the raw register offset, that one has an underscore sa a
prefix. The define (possibly parametrized) without the underscore is
the one people should normally use, since it will take into account
all the parameters and other potential offsets that are needed.

Fix up the few stragglers that don't follow this convention.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446672017-24497-14-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NChris Wilson <chris@chris-wilson.co.uk>

If we ignore the BXT situation, we can observe that the only variables
affecting gpio_mmio_base is IS_VALLEVIEW and HAS_GMCH_DISPLAY. The BXT
situation we can fit into the same pattern if we change gmbus_pins_bxt[]
to house the GMCH GPIO register offsets (like we do for all other
platfotms). So let's do that.

We could even simplify the VLV situation more by including the
display_mmio_offset in the GPIO register defines, but let's leave it be
for now.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446672017-24497-13-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Store the DVO SRCDIM register offset alongside the DVO control register
offset in intel_dvo_device. This gets rid of the switch statement whose
case values are the DVO control register offsets. Such a construct would
cause problems for register type safety.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446672017-24497-12-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NChris Wilson <chris@chris-wilson.co.uk>

Replace the is_sdvob bool and some sdvo_reg checks with enum port. This
makes the SDVO code look more modern, and gets rid of explicit register
offset checks in the code which will hamper register type checking.

v2: Add assert_sdvo_port_valid() (Chris)
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1446838199-3666-1-git-send-email-ville.syrjala@linux.intel.com

Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446672017-24497-9-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NChris Wilson <chris@chris-wilson.co.uk>

Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

It was created at 'commit aabc95dc (drm/i915: Dont -ETIMEDOUT
on identical new and previous (count, crc).")' becase the counter
wasn't reliable.

Now that we properly wait for the counter to be reset we can rely
a bit more in the counter.

Also that patch stopped to return -ETIMEDOUT so the test case is
unable to skip when it is unreliable and end up in many fails
that should be skip instead.

So, with the counter more reliable we can remove
this hack that just makes things more confusing when test cases
are really expecting the same CRC and let test case skip if that's
not the case.
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

According to VESA DP spec TEST_CRC_COUNT (Bits 3:0) at
TEST_SINK_MISC (00246h) is "Reset to 0 when TEST_SINK bit 0 = 0;

So let's give few vblanks so we are really sure that this counter
is really zeroed on the next sink_crc read.
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

According to VESA DP Spec, setting TEST_SINK_START (bit 0)
of TEST_SINK (00270h) "Stop/Start calculating CRC on the next frame"

So let's wait at least 1 vblank to really say the calculation
stopped or started.
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Signed-off-by: NPatrik Jakobsson <patrik.jakobsson@linux.intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1447084107-8521-13-git-send-email-patrik.jakobsson@linux.intel.com

v2: Use _unsafe (Jani)
v3: Allow specifying specific DC-states instead of just DC6 (Imre)
Signed-off-by: NPatrik Jakobsson <patrik.jakobsson@linux.intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1447682467-6237-3-git-send-email-patrik.jakobsson@linux.intel.com