Prep work for some nice documentation. Requires that we export the
display irq enable/disable functions on ilk/ibx. But we already export
them for vlv/i915. So not more inconsistency.

v2: Rebase on top of skl stage 1.
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>

Move the duplicated DIV_ROUND_CLOSEST_ULL macro into the intel_drv.h
header file so that it can be shared between intel_display.c
and intel_panel.c.
Signed-off-by: NU. Artie Eoff <ullysses.a.eoff@intel.com>
Reviewed-By: NJoe Konno <joe.konno@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

It's the new world order!

Not going full monty on these here and rolling this out throughout the
subsequent call chains since this is just for the kerneldoc. Later on
we can go more crazy, especially once we've embedded drm_device
correctly.

v2: Also frob the runtime_pm functions ...
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Double negations just parse harder. Also this allows us to ditch some
init code since clearing to 0 dtrt. Also ditch the assignment in
intel_pm_setup, that's not redundant since we do the assignement now
while setting up interrupts.

While at it do engage in a bit of OCD and wrap up the few lines of
setup/teardown code into little helper functions: intel_irq_fini for
cleanup and intel_irq_init_hw for hw setup.

v2: Use _install/_uninstall for the new wrapper function names as
Paulo suggested.
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Allows us to mark it static and so forgoe the kerneldoc for it.

Note that intel_power_domains_fini is also called from failure paths
in the driver load sequence. But the call to runtime_pm_disable for
that is harmless since by default runtime pm is already disabled.

v2: Augment the commit message as discussed with Imre on irc.
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

I've decided to not move intel_display_port_power_domain because
that's just a hack in our design ...
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

- fini goes with init, so call it intel_power_domains_fini. While
  at it shovel some of the fini code that leaked out of it back in.

- give power_enabled functions the verb _is_ to make the meaning clearer.
  Also use a __ prefix instead of _unlocked to really discourage users.

- rename runtime_pm_init/fini to enable/disable since that's what they do.
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Geez is the audio hack ugly.
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
[danvet: Rebased on top of the skl patches.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Oh well.

v2: Fix one more spelling fail Paulo spotted.
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

It can be handy to get the number of planes for this pipe, ie including
the primary plane to loop over them. Introduce a little function to do
so.
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

I shouldn't ask everyone to do this and fail myself ...

This extracts all the frontbuffer tracking functions into
intel_frontbuffer.c, adds a DOC overview section and also adds the
missing kerneldoc for i915_gem_track_fb and also pulls it into the
same section for convenience.

v2: Don't forget about the header files.

v3: Oops, might check compilation next time around. To make my life
easier drop the increase_pllclock from set_base_atomic since really,
it doesn't matter if you see your Oops or kgdb with a tiny bit of lag.

v4: Try to better explain how to actually use this, requested by Paulo
on irc.

v5: Explain invalidate/flush a bit clearer.

v6: s/business/busyness/
Acked-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Vandana Kannan <vandana.kannan@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>

Requested by Chris, and also requested to keep it since it's a
more accurate name in his opinion.

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This new struct will be the storage of src and dst coordinates
between the check and commit stages of a plane update.
Signed-off-by: NGustavo Padovan <gustavo.padovan@collabora.co.uk>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Long ago, back in the racy haydays of 915gm interrupt handling, page
flips would occasionally go astray and leave the hardware stuck, and the
display not updating. This annoyed people who relied on their systems
being able to display continuously updating information 24/7, and so
some code to detect when the driver missed the page flip completion
signal was added. Until recently, it was presumed that the interrupt
handling was now flawless, but once again Simon Farnsworth has found a
system whose display will stall. Reinstate the pageflip stall detection,
which works by checking to see if the hardware has been updated to the
new framebuffer address following each vblank. If the hardware is
scanning out from the new framebuffer, but we still think the flip is
pending, then we kick our driver into submision.

This is a continuation of the effort started with
commit 4e5359cd
Author: Simon Farnsworth <simon.farnsworth@onelan.co.uk>
Date:   Wed Sep 1 17:47:52 2010 +0100

    drm/i915: Avoid pageflipping freeze when we miss the flip prepare interrupt

This now includes a belt-and-braces approach to make sure the driver
(or the hardware) doesn't miss an interrupt and cause us to stop
updating the display should the unthinkable happen and the pageflip fail - i.e.
that the user is able to continue submitting flips.

v2: Cleanup, refactor, and rename
v3: Only start counting vblanks after the flip command has been seen by
    the hardware.
v4: Record the seqno after we touch the ring, or else there may be no
    seqno allocated yet.
v5: Rebase on mmio-flip.
v6: Rebase, rebase.
Reported-by: NSimon Farnsworth <simon@farnz.org.uk>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=75502Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> [v4]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The power sequencer loses its state when the disp2d power well is down.
Clear the dev_priv->pps_pipe tracking so that the power sequencer state
gets reinitialized the next time it's needed.

v2: Fix the pps_mutex vs. power_domain mutex deadlock by taking power
    domain reference first
v3: Rename from edp_pps_(un)lock() to just pps_(un)lock() for the future,
    update due to backlight code changes
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

VLV/CHV have a per-pipe panel power sequencer which locks onto the
port once used. We need to keep track wich power sequencers are
locked to which ports.

v2: remove spurious whitespace change, rebase due to backlight changes (Imre)
Reviewed-by: NAntti Koskipaa <antti.koskipaa@linux.intel.com>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
[danvet: Break some really long lines to appease checkpatch a bit.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

As we may query the edid multiple times following a detect, record the
EDID found during output discovery and reuse it. This is a separate
issue from caching the output EDID across detection cycles.

v2: Implement connector->force() callback so that edid is associated
with the connector for user overrides as well (Ville)
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Just pass the intel_crtc around instead of dev_priv+pipe.

Also make intel_wait_for_pipe_off() static since it's only used in
intel_display.c.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Tested-by: NThomas Richter <richter@rus.uni-stuttgart.de>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This gets us out of our init code and out to userspace quite a bit
faster, but does open us up to some bugs given the state of our init
time locking.

v2: switch to async_schedule (Chris)
    check with lockdep, seems happy (Jesse)
    move hotplug enable flag set to fbdev_initial_config (Jesse)
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
[danvet: Rebase on top of the dev_priv->enable_hotplug_processing
removal.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Make backlight class sysfs bl_power a sub-state of backlight enabled, if
a backlight power connector callback is defined. It's up to the
connector callback to handle the sub-state, typically in a way that
respects panel power sequencing.

v2: Post the version that does not oops. *facepalm*.
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Reviewed_by: Clinton Taylor <Clinton.A.Taylor@intel.com>
Tested_by: Clinton Taylor <Clinton.A.Taylor@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Primary planes support 180 degree rotation. Expose the feature
through rotation drm property.

v2: Calculating linear/tiled offsets based on pipe source width and
height. Added 180 degree rotation support in ironlake_update_plane.

v3: Checking if CRTC is active before issueing update_plane. Added
wait for vblank to make sure we dont overtake page flips. Disabling
FBC since it does not work with rotated planes.

v4: Updated rotation checks for pending flips, fbc disable. Creating
rotation property only for Gen4 onwards. Property resetting as part
of lastclose.

v5: Resetting property in i915_driver_lastclose properly for planes
and crtcs. Fixed linear offset calculation that was off by 1 w.r.t
width in i9xx_update_plane and ironlake_update_plane. Removed tab
based indentation and unnecessary braces in intel_crtc_set_property
and intel_update_fbc. FBC and flip related checks should be done only
for valid crtcs.

v6: Minor nits in FBC disable checks for comments in intel_crtc_set_property
and positioning the disable code in intel_update_fbc.

v7: In case rotation property on inactive crtc is updated, we return
successfully printing debug log as crtc is inactive and only property change
is preserved.

v8: update_plane is changed to update_primary_plane, crtc->fb is changed to
crtc->primary->fb  and return value of update_primary_plane is ignored.

v9: added rotation property to primary plane instead of crtc. Removing reset
of rotation property from lastclose. rotation_property is moved to
drm_mode_config, so drm layer will take care of resetting. Adding updation of
fbc when rotation is set to 0. Allowing rotation only if value is
different than old one.

v10: Calling intel_primary_plane_setplane instead of update_primary_plane in
set_property(Daniel).

v11: Using same set_property function for both primary and sprite, Adding
primary plane specific code in the same function (Matt).

v12: Removing disabling/ enabling of fbc from set_property because it is done
from intel_pipe_set_base. Other formatting

v13: we need to call disable_fbc before changing the rotation to 180,
disable_fbc from intel_pipe_set_base gets called very late, that will
be used to re-enable fbc if rotation is set to 0 (Ville).

Testcase: igt/kms_rotation_crc
Signed-off-by: NUma Shankar <uma.shankar@intel.com>
Signed-off-by: NSagar Kamble <sagar.a.kamble@intel.com>
Signed-off-by: NSonika Jindal <sonika.jindal@intel.com>
[danvet: Add FIXME to explain why we need the open-coded update_fbc
hunk to disable fbc when rotated 180 degree. And make checkpatch
happier.]
Acked-by: NMatt Roper <matthew.d.roper@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Atm we may leave eDP VDD enabled during system suspend after the CRTCs
are disabled through an HPD->DPCD read event. So disable VDD during
suspend at a point when no HPDs can occur.

Note that runtime suspend doesn't have the same problem, since there the
RPM ref held by VDD provides already the needed serialization.

v2:
- add note to commit message about the runtime suspend path (Ville)
- use edp_panel_vdd_off_sync(), so we can keep the WARN in
  edp_panel_vdd_off() (Ville)
v3:
- rebased on -fixes (for_each_intel_encoder()->list_for_each_entry())
  (Imre)
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> (v2)
Cc: stable@vger.kernel.org (3.16+)
[Jani: fix sparse warning reported by Fengguang Wu]
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

intel_enable_pipe_a() gets called with all the modeset locks already
held (by drm_modeset_lock_all()), so trying to grab the same
locks using another drm_modeset_acquire_ctx is going to fail miserably.

Move most of the drm_modeset_acquire_ctx handling (init/drop/fini)
out from intel_{get,release}_load_detect_pipe() into the callers
(intel_{crt,tv}_detect()). Only the actual locking and backoff
handling is left in intel_get_load_detect_pipe(). And in
intel_enable_pipe_a() we just share the mode_config.acquire_ctx from
drm_modeset_lock_all() which is already holding all the relevant locks.

It's perfectly legal to lock the same ww_mutex multiple times using the
same ww_acquire_ctx. drm_modeset_lock() will convert the returned
-EALREADY into 0, so the caller doesn't need to do antyhing special.

Fixes a hang on resume on my 830.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Cc: stable@vger.kernel.org
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

Rather than take and release the console_lock() around a non-existent
DRM_I915_FBDEV, move the lock acquisation into the callee where it will
be compiled out by the config option entirely. This includes moving the
deferred fb_set_suspend() dance and encapsulating it entirely within
intel_fbdev.c.

v2: Use an integral work item so that we can explicitly flush the work
upon suspend/unload.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
[danvet: Add the flush_work in fbdev_fini per the mailing list
discussion. And s/BUG_ON/WARN_ON/ because.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

845/865 support different cursor sizes as well, albeit a bit differently
than later platforms. Add the necessary code to make them work.

Untested due to lack of hardware.

v2: Warn but accept invalid stride (Chris)
    Rewrite the cursor size checks for other platforms (Chris)
v3: More polish and magic to the cursor size checks (Chris)
v4: Moar polish and a comment (Chris)
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

If there are pending page flips when the fd gets closed those page
flips may have events associated to them. When the page flip eventually
completes it will queue the event to file_priv->event_list, but that
may be too late and file_priv->event_list has already been cleaned up.
Thus we leak a bit of kernel memory in the form of the event structure.

To avoid such problems clear out such pending events from
intel_crtc->unpin_work at ->preclose(). Any event that already made it
to file_priv->event_list will get cleaned up by the drm_release_events()
a bit later.

We can ignore the file_priv->event_space accounting since file_priv is
going away. This is already how drm core deals with pending vblank
events, which are maintained by the drm core.

What saves us from a total disaster (ie. dereferencing and alrady
freed file_priv) is the fact that the fb descruction triggers a modeset
and there we wait for pending flips.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Propagate the error from intel_update_plane() up through
intel_plane_restore() to the caller. This will be used for
rollback purposes when setting properties fails.

Cc: dri-devel@lists.freedesktop.org
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The sprite planes (in fact all display planes starting from gen4)
support 180 degree rotation. Add the relevant low level bits to the
sprite code to make use of that feature.

The upper layers are not yet plugged in.

v2: HSW handles the rotated buffer offset automagically

v3: BDW also handles the rotated buffer offset automagically

Testcase: igt/kms_rotation_crc
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NSagar Kamble <sagar.a.kamble@intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Share the waitqueue that drm_irq uses when performing the vblank evade
trick for atomic pipe updates.

v2: Keep intel_pipe_handle_vblank() (Chris)
Suggested-by: NDaniel Vetter <daniel@ffwll.ch>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

For Gen < 8, set M2_N2 registers on every mode set. This is required to make
sure M2_N2 registers are set during boot, resume from sleep for cross-
checking the state. The register is set only if DRRS is supported.

v2: Patch rebased

v3: Daniel's review comments
	- Removed HAS_DRRS(dev) and added bool has_drrs to pipe_config to
	track drrs support

v4: Jesse's review comments
	- Made changes to set m2_n2 in intel_dp_set_m_n()
Signed-off-by: NVandana Kannan <vandana.kannan@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This will be needed by an upcoming patch too that needs to sanitize the
VDD state during resume. The additional async disabling is only needed
for the resume path, here it doesn't make a difference since we enable
VDD right after the sanitize call.

v2:
- don't set intel_dp ptr for non-eDP encoders (Ville)
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Historically we've exposed the full backlight PWM duty cycle range to
the userspace, in the name of "mechanism, not policy". However, it turns
out there are both panels and board designs where there is a minimum
duty cycle that is required for proper operation. The minimum duty cycle
is available in the VBT.

The backlight class sysfs interface does not make any promises to the
userspace about the physical meaning of the range
0..max_brightness. Specifically there is no guarantee that 0 means off;
indeed for acpi_backlight 0 usually is not off, but the minimum
acceptable value.

Respect the minimum backlight, and expose the range acceptable to the
hardware as 0..max_brightness to the userspace via the backlight class
device; 0 means the minimum acceptable enabled value. To switch off the
backlight, the user must disable the encoder.

As a side effect, make the backlight class device max brightness and
physical PWM modulation frequency (i.e. max duty cycle)
independent. This allows a follow-up patch to virtualize the max value
exposed to the userspace.
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
[danvet: s/BUG_ON/WARN_ON/]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Now that we use the runtime IRQ enable/disable functions in our suspend
path, we can simply check the pm._irqs_disabled flag everywhere.  So
rename it to catch the users, and add an inline for it to make the
checks clear everywhere.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Move it from hsw_power_well_post_enable() (intel_pm.c) to i915_irq.c
so we can reuse the nice IRQ macros we have there. The main difference
is that now we're going to check if the IIR register is non-zero when
we try to re-enable the interrupts.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Traditionally we use genX_ for GT/render stuff and the codenames for
display stuff. But the gt and pm interrupt handling functions on
gen5/6+ stuck out as exceptions, so convert them.

Looking at the diff this nicely realigns our ducks since almost all
the callers are already platform-specific functions following the
genX_ pattern.

Spotted while reviewing some internal rps patches.

No function change in this patch.
Acked-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

In the future, we'll need the height of the fb to fetch from memory for
WM computation.
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Create and attach the drm property to set aspect ratio. If there is no user
specified value, then PAR_NONE/Automatic option is set by default. User can
select aspect ratio 4:3 or 16:9. The aspect ratio selected by user would
come into effect with a mode set.

v2: Modified switch case to include aspect ratio enum changes

v3: Modified the patch according the change in the earlier patch to return
errno in case property creation fails. With this change, property will be
attached only if creation is successful
Signed-off-by: NVandana Kannan <vandana.kannan@intel.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

I've tried to split this up, but all the changes are so tightly
related that I didn't find a good way to do this without breaking
bisecting. Essentially this completely changes how psr is glued into
the overall driver, and there's not much you can do to soften such a
paradigm change.

- Use frontbuffer tracking bits stuff to separate disable and
  re-enable.

- Don't re-check everything in the psr work. We have now accurate
  tracking for everything, so no need to check for sprites or tiling
  really. Allows us to ditch tons of locks.

- That in turn allows us to properly cancel the work in the disable
  function - no more deadlocks.

- Add a check for HSW sprites and force a flush. Apparently the
  hardware doesn't forward the flushing when updating the sprite base
  address. We can do the same trick everywhere else we have such
  issues, e.g. on baytrail with ... everything.

- Don't re-enable psr with a delay in psr_exit. It really must be
  turned off forever if we detect a gtt write. At least with the
  current frontbuffer render tracking. Userspace can do a busy ioctl
  call or no-op pageflip to re-enable psr.

- Drop redundant checks for crtc and crtc->active - now that they're
  only called from enable this is guaranteed.

- Fix up the hsw port check. eDP can also happen on port D, but the
  issue is exactly that it doesn't work there. So an || check is
  wrong.

- We still schedule the psr work with a delay. The frontbuffer
  flushing interface mandates that we upload the next full frame, so
  need to wait a bit. Once we have single-shot frame uploads we can do
  better here.

v2: Don't enable psr initially, rely upon the fb flush of the initial
plane setup for that. Gives us more unified code flow and makes the
crtc enable sequence less a special case.

v3: s/psr_exit/psr_invalidate/ for consistency

v4: Fixup whitespace.

v5: Correctly bail out of psr_invalidate/flush when
dev_priv->psr.enabled is NULL. Spotted by Rodrigo.

v6:
- Only schedule work when there's work to do. Fixes WARNINGs reported
  by Rodrigo.
- Comments Chris requested to clarify the code.

v7: Fix conflict on rebase (Rodrigo)

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> (v6)
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

On VLV, after i915_pm_suspend display power wells are staying
power ungated. So, after initiating mem sleep "echo mem > /sys/power/state"
Display is staing D0 State. There might be better way/place to power gate
these wells. Also, we need to make sure that if wells are power gated due to
DPMS OFF sequence, they need not be turned off by i915_pm_suspend again.

v2: Extracted helper for intel_crtc_disable and power gating CRTC power wells.
[Daniel]

Cc: Imre Deak <imre.deak@intel.com>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Change-Id: I34c80da66aa24c423a5576c68aa1f3a8d0f43848
Signed-off-by: NBorun Fu <borun.fu@intel.com>
Signed-off-by: NSagar Kamble <sagar.a.kamble@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This adds DP 1.2 MST support on Haswell systems.

Notes:
a) this reworks irq handling for DP MST ports, so that we can
avoid the mode config locking in the current hpd handlers, as
we need to process up/down msgs at a better time.

Changes since v0.1:
use PORT_PCH_HOTPLUG to detect short vs long pulses
add a workqueue to deal with digital events as they can get blocked on the
main workqueue beyong mode_config mutex
fix a bunch of modeset checker warnings
acks irqs in the driver
cleanup the MST encoders

Changes since v0.2:
check irq status again in work handler
move around bring up and tear down to fix DPMS on/off
use path properties.

Changes since v0.3:
updates for mst apis
more state checker fixes
irq handling improvements
fbcon handling support
improved reference counting of link - fixes redocking.

Changes since v0.4:
handle gpu reset hpd reinit without oopsing
check link status on HPD irqs
fix suspend/resume

Changes since v0.5:
use proper functions to get max link/lane counts
fix another checker backtrace - due to connectors disappearing.
set output type in more places fro, unknown->displayport
don't talk to devices if no HPD asserted
check mst on short irqs only
check link status properly
rebase onto prepping irq changes.
drop unsued force_act

Changes since v0.6:
cleanup unused struct entry.

[airlied: fix some sparse warnings].
Reviewed-by: NTodd Previte <tprevite@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>