Factor out the logic to decide whether the newly calculated dividers are
better than the best found so far. Do this for clarity and to prepare
for the upcoming BXT helper needing the same.

No functional change.
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

intel_plane->obj is not used anymore so kill it. Also don't pass both
the fb and obj to the sprite .update_plane() hook, as just passing the fb
is enough.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Rewrite commit 31685c25
Author: Deepak S <deepak.s@linux.intel.com>
Date:   Thu Jul 3 17:33:01 2014 -0400

    drm/i915/vlv: WA for Turbo and RC6 to work together.

Other than code clarity, the major improvement is to disable the extra
interrupts generated when idle.  However, the reclocking remains rather
slow under the new manual regime, in particular it fails to downclock as
quickly as desired. The second major improvement is that for certain
workloads, like games, we need to combine render+media activity counters
as the work of displaying the frame is split across the engines and both
need to be taken into account when deciding the global GPU frequency as
memory cycles are shared.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Deepak S <deepak.s@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Deepak S<deepak.s@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We don't want to end up in a state where we track that the pipe has its
primary plane enabled when primary plane registers are programmed with
values that look possible but the plane actually disabled.

Refuse to read out the fb state when the primary plane isn't enabled.
Suggested-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Suggested-by: NMatt Roper <matthew.d.roper@intel.com>
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Reviewed-by: NMatt Roper <matthew.d.roper@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Reported-by: NAndrey Skvortsov <andrej.skvortzov@gmail.com>
Reported-by: NSteven Rostedt <rostedt@goodmis.org>
Reference: http://mid.gmane.org/20150203191507.GA2374@crion86Tested-by: NSteven Rostedt <rostedt@goodmis.org>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

We accidentally pass 'pipe' instead of 'port' to CHV_PLL_DW8() and
with PIPE_C we end up at register offset 0x8320 which isn't the
0x8020 we wanted. Fix it.

The problem was fortunately caught by the sanity check in vlv_dpio_read():
WARNING: CPU: 1 PID: 238 at ../drivers/gpu/drm/i915/intel_sideband.c:200 vlv_dpio_read+0x77/0x80 [i915]()
DPIO read pipe C reg 0x8320 == 0xffffffff

The problem got introduced with this commit:
 commit 71af07f91f12bbab96335e202c82525d31680960
 Author: Vijay Purushothaman <vijay.a.purushothaman@linux.intel.com>
 Date:   Thu Mar 5 19:33:08 2015 +0530

    drm/i915: Update prop, int co-eff and gain threshold for CHV

Cc: Vijay Purushothaman <vijay.a.purushothaman@linux.intel.com>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NTodd Previte <tprevite@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Ignore the current state of the pipe and just check crtc_state->enable
and the number of FDI lanes required. This means we don't accidentally
mistake the FDI lanes as being available of one of the pipes just
happens to be disabled at the time of the check. Also we no longer
consider pipe C to require FDI lanes when it's driving the eDP
transcoder.

We also take the opportunity to make the code a bit nicer looking by
hiding the ugly bits in the new pipe_required_fdi_lanes() function.

Cc: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NAnder Conselvan de Oliveira <conselvan2@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The logic in the FDI lane checks is very hard for my poor brain to
grasp. Rewrite it in a more straightforward way.

Cc: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NAnder Conselvan de Oliveira <conselvan2@gmail.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Remove the global modeset resource function that would disable the
bifurcation bit, and instead enable/disable it when enabling the pch
transcoder. The mode set consistency check should prevent us from
disabling the bit if pipe C is enabled so the change should be safe.

Note that this doens't affect the logic that prevents the bit being
set while a pipe is active, since the patch retains the behavior of
only chaging the bit if necessary. Because of the checks during mode
set, the first change would necessarily happen with both pipes B and
C disabled, and any subsequent write would be skipped.

v2: Only change the bit during pch trancoder enable. (Ville)
Signed-off-by: NAnder Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

No need to go dig throguh intel_crtc->base.cursor when we already have
the same thing as 'plane' local variable.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: NMatt Roper <matthew.d.roper@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

These are now called from the plane commit hooks, so they really need to
be fast or else we risk atomic update failures. So kill the debug prints
which are slowing things down massively.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: NMatt Roper <matthew.d.roper@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

intel_user_framebuffer_destroy() requires the struct_mutex for its
object bookkeeping, so this means that all calls to
drm_framebuffer_unreference must not hold that lock.

Regression from commit ab8d6675
Author: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Date:   Mon Feb 2 15:44:15 2015 +0000

    drm/i915: Track old framebuffer instead of object

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=89166
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
[danvet: Clarify commit message slightly.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

PFI credit programming is required when CD clock (related to data flow from
display pipeline to end display) is greater than CZ clock (related to data
flow from memory to display plane). This programming should be done when all
planes are OFF to avoid intermittent hangs while accessing memory even from
different Gfx units (not just display).

If cdclk/czclk >=1, PFI credits could be set as any number. To get better
performance, larger PFI credit can be assigned to PND. Otherwise if
cdclk/czclk<1, the default PFI credit of 8 should be set.

v2:
    - Change log to lower log level instead of DRM_ERROR
    - Change function name to valleyview_program_pfi_credits
    - Move program PFI credits to modeset_init instead of intel_set_mode
    - Change magic numbers to logical constants

[vsyrjala v3:
 - only program in response to cdclk update
 - program the credits also when cdclk<czclk
 - add CHV bits
 v4:
 - Change CHV cdclk<czclk credits to 12 (Vijay)]
Signed-off-by: NVidya Srinivas <vidya.srinivas@intel.com>
Signed-off-by: NGajanan Bhat <gajanan.bhat@intel.com>
Signed-off-by: NVandana Kannan <vandana.kannan@intel.com>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NVijay Purushothaman <vijay.a.purushothaman@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This patch implements latest PHY changes in Gain, prop and int co-efficients
based on the vco freq.

v2: Split the original changes into multiple smaller patches based on
review by Ville

v3: Addressed Ville's review comments. Fixed the error introduced in v2.
Clear the old bits before we modify those bits as part of RMW.

v4: TDC target cnt is 10 bits and not 8 bits (Ville)
Signed-off-by: NVijay Purushothaman <vijay.a.purushothaman@linux.intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Initialize lock detect threshold and select coarse threshold for the
case where M2 fraction division is disabled.

v2: Split the changes into multiple smaller patches (Ville)
v3: Clear out the old bits before we modify those bits as RMW (Ville)
v4: Reset coarse threshold when M2 fraction is enabled (Ville)
Signed-off-by: NVijay Purushothaman <vijay.a.purushothaman@linux.intel.com>
Reviewed-by: NVille Syrjala <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

v2 : Handle M2 frac division for both M2 frac and int cases

v3 : Addressed Ville's review comments. Cleared the old bits for RMW

v4 : Fix feedfwd gain (Ville)
Signed-off-by: NVijay Purushothaman <vijay.a.purushothaman@linux.intel.com>
Reviewed-by: NVille Syrjala <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

With the switch to atomic plumbing for planes, some of our commit-time
work (e.g., watermarks) is done after the new atomic state is swapped
into the relevant DRM object, but before the DRM core has a chance to
update its legacy state values.  Switch intel_crtc_active() to look at
the state objects rather than legacy fields to ensure we operate on the
proper values.

Note that we're continuing to use intel_crtc->active here for the time
being since crtc->state isn't really hooked up yet.  Once CRTC states
are wired up properly, we'll want to switch this over to use
crtc->state->active instead.

v2: Switch back to intel_crtc->active for now; when Ander's work on CRTC
    states is ready, we can flip this over to use crtc->state->active
    instead. (Ville)

Cc: Ander Conselvan De Oliveira <conselvan2@gmail.com>
Suggested-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NMatt Roper <matthew.d.roper@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The specs seem to be full of misinformation wrt. the Punit register
0x36. Some versions still show the old VLV bit layout, some the new
layout, and all of them seem to tell us nonsense about the cdclk
value encoding.

Testing on actual hardware has shown that we simply need to program
the desired CCK divider into the Punit register using the new layout of
the bits. Doing that, the status bit change to indicate the same value,
and the CCK 0x6b register also changes accordingly to indicate that CCK
is now using the new divider.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NVijay Purushothaman <vijay.a.purushothaman@linux.intel.com>
Reviewed-by: NYogesh Mohan Marimuthu <yogesh.mohan.marimuthu@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Supposedly CHV can sustain a pixel clock of up to 95% of
cdclk, as opposed to the 90% limit that was used old older
platforms. Update the cdclk selection code to allow for this.

This will allow eg. HDMI 4k modes with their 297MHz pixel clock
while still respecting the 320 MHz cdclk limit on CHV.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NVijay Purushothaman <vijay.a.purushothaman@linux.intel.com>
Reviewed-by: NYogesh Mohan Marimuthu <yogesh.mohan.marimuthu@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

So try to enumerate eDP unconditionally in those cases.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
[danvet: Add wa tag Damien dug out.]
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Apparently, this has never worked reliably and is currently disabled. Also, the
gains are not particularly impressive. Thus rather than try to keep unused code
from decaying and having to update it for other driver changes, it was decided
to simply remove it.

For: VIZ-5115
Signed-off-by: NJohn Harrison <John.C.Harrison@Intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We need to disable all sprite planes when disabling the CRTC.  We had
been using the top-level atomic 'disable' entrypoint to accomplish this,
which was wrong.  Not only can this lead to various locking issues, it
also modifies the actual plane state, making it impossible to restore
the plane properly later.  For example, a DPMS off followed by a DPMS on
will result in any sprite planes in use not being restored properly.

The proper solution here is to call directly into our 'commit plane'
hook with a copy of the plane's current state that has 'visible' set to
false.  Committing this dummy state will turn off the plane, but will
not touch the actual plane->state pointer, allowing us to properly
restore the plane state later.
Signed-off-by: NMatt Roper <matthew.d.roper@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

When logging that full mode switch is necessary, log which connector,
encoder or crtc has caused it, so it is easier to figure out what is
goind on by just looking at the log.
Signed-off-by: NAnder Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We have similar macros for crtcs and encoders, and the pattern happens
often enough to justify the macro.
Signed-off-by: NAnder Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The current minimum vco frequency leaves us with a gap in our supported
frequencies at 233-243 MHz. Your typical 2560x1440@60 display wants a
pixel clock of 241.5 MHz, which is just withing that gap. Reduce the
allowed vco min frequency to 4.8GHz to reduce the gap to 233-240 MHz,
and thus allow such displays to work.

4.8 GHz is actually the documented (at least in some docs) limit of the
PLL, and we just picked 4.86 GHz originally because that was the lowest
value produced by the PLL spreadsheet, which obviously didn't consider
2560x1440 displays.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NVijay Purushothaman <vijay.a.purushothaman@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This reverts commit 3f678c96.

We've been a bit too optimistic with this one here :(

The trouble is that internally we're still using these plane
update/disable hooks. Which was totally ok pre-atomic since the drm
core did all the book-keeping updating and these just mostly updated
hw state. But with atomic there's lots more going on, and it causes
heaps of trouble with the load detect code.

This one specifically cause a deadlock since both the load detect code
and the nested plane atomic helper functions tried to grab the same
locks. It only blows up because of the evil tricks though we play with
the implicit ww acquire context.

Applying this revert unearths the NULL deref on already freed
framebuffer objects reported as a regression in 4.0 by various people.

Fixing this will be fairly invasive, hence revert even for the
4.1-next queue.

Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Bolle <pebolle@tiscali.nl>
Acked-by: NMatt Roper <matthew.d.roper@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>

Implicit usage of local variables in macros isn't exactly the greatest
thing in the world, especially when that variable is the drm device and
we want to move towards a broader use of the i915 device structure.

Let's make for_each_sprite() take dev_priv as its first argument then.
Suggested-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Reviewed-by: Chris Wilson <chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Implicit usage of local variables in macros isn't exactly the greatest
thing in the world, especially when that variable is the drm device and
we want to move towards a broader use of the i915 device structure.

Let's make for_each_plane() take dev_priv as its first argument then.
Suggested-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Reviewed-by: Chris Wilson <chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The cursor size fields in intel_crtc just duplicate the data from
cursor->state.crtc_{w,h} so we don't need them any more.  Worse, their
use in the watermark code actually introduces a subtle bug since they
don't get updated to mirror the state values until the plane commit
stage, which is *after* we've already used them to calculate new
watermark values.  This happens because we had to move watermark updates
slightly earlier (outside vblank evasion) in commit

        commit 32b7eeec
        Author: Matt Roper <matthew.d.roper@intel.com>
        Date:   Wed Dec 24 07:59:06 2014 -0800

            drm/i915: Refactor work that can sleep out of commit (v7)

Dropping the intel_crtc fields and just using the state values (which
are properly updated by the time watermark updates happen) should solve
the problem.

Aside from the actual removal of the struct fields (which are formatted
in a way that I couldn't figure out how to match in Coccinelle), the
rest of this patch was generated via the following semantic patch:

        // Drop assignment
        @@
        struct intel_crtc *C;
        struct drm_plane_state S;
        @@
        (
        - C->cursor_width = S.crtc_w;
        |
        - C->cursor_height = S.crtc_h;
        )

        // Replace usage
        @@
        struct intel_crtc *C;
        expression E;
        @@
        (
        - C->cursor_width
        + C->base.cursor->state->crtc_w
        |
        - C->cursor_height
        + C->base.cursor->state->crtc_h
        |
        - to_intel_crtc(E)->cursor_width
        + E->cursor->state->crtc_w
        |
        - to_intel_crtc(E)->cursor_height
        + E->cursor->state->crtc_h
        )

v2: Rebase

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Joe Konno <joe.konno@linux.intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=89346Signed-off-by: NMatt Roper <matthew.d.roper@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

plane->state->fb and plane->fb should always reference the same FB so
that atomic and legacy codepaths have the same view of display state.
However, there are some places in kernel code that directly set
plane->fb and neglect to update plane->state->fb. If we never do a
successful update through the atomic pipeline, the RmFB cleanup code
will look at the plane->state->fb pointer, which has never actually
been set to a legitimate value, and try to clean it up, leading to
BUG's.

Add a quick helper function to synchronize plane->state->fb with
plane->fb and call it everywhere the driver tries to manually set
plane->fb outside of the atomic pipeline. In this function, use
drm_atomic_set_fb_for_plane instead of writing plane->state->fb
directly to keep the reference count right.

This is modified from Matt Roper's patch to drm-intel-nightly with
commit id

commit afd65eb4
Author: Matt Roper <matthew.d.roper@intel.com>
Date:   Tue Feb 3 13:10:04 2015 -0800

    drm/i915: Ensure plane->state->fb stays in sync with plane->fb

However this bug exists in mainline kernel too, so I created this to fix
it in mainline kernel.

A minor change is to use drm_atomic_set_fb_for_plane instead of update
reference count manually.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=88909
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=93711Signed-off-by: NXi Ruoyao <xry111@outlook.com>
Reviewed-by: NMatt Roper <matthew.d.roper@intel.com>
[Jani: included the patch notes in the commit message]
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

The kernel in_irq() function tests for hard-IRQ context only, so if a
system is run with the kernel 'threadirqs' option selected, the test in
intel_check_page_flip() generates lots of warnings, because then it gets
called in soft-IRQ context.

We can instead use in_interrupt() which allows for either type of
interrupt, while still detecting and complaining about misuse of the
page flip code if it is ever called from non-interrupt context.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=89321Signed-off-by: NDave Gordon <david.s.gordon@intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Cc: stable@vger.kernel.org
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

commit a8c6ecb3
Merge: 8dd0eb35 9eccca08
Author: Dave Airlie <airlied@redhat.com>
Date:   Mon Mar 9 19:58:30 2015 +1000

    Merge tag 'v4.0-rc3' into drm-next

managed to pick the wrong code to resolve the conflict and left us with
a mutex_lock(struct_mutex) without the mutex_unlock(struct_mutex) leading
to a deadlock. Fix the problem by recovering the correct code which doesn't
need the lock.

Cc: Dave Airlie <airlied@redhat.com>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

Use cases like rotation require these hooks to have some context so they
know how to prepare and cleanup the frame buffer correctly.

For i915 specifically, object backing pages need to be mapped differently
for different rotation modes and the driver needs to know which mapping to
instantiate and which to tear down when transitioning between them.

v2: Made passed in states const. (Daniel Vetter)

[airlied: add mdp5 and atmel fixups]
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: NRob Clark <robdclark@gmail.com>
Signed-off-by: NDave Airlie <airlied@redhat.com>

This is a tricky story of the new atomic state handling and the legacy
code fighting over each another. The bug at hand is an underrun of the
framebuffer reference with subsequent hilarity caused by the load
detect code. Which is peculiar since the the exact same code works
fine as the implementation of the legacy setcrtc ioctl.

Let's look at the ingredients:

- Currently our code is a crazy mix of legacy modeset interfaces to
  set the parameters and half-baked atomic state tracking underneath.
  While this transition is going we're using the transitional plane
  helpers to update the atomic side (drm_plane_helper_disable/update
  and friends), i.e. plane->state->fb. Since the state structure owns
  the fb those functions take care of that themselves.

  The legacy state (specifically crtc->primary->fb) is still managed
  by the old code (and mostly by the drm core), with the fb reference
  counting done by callers (core drm for the ioctl or the i915 load
  detect code). The relevant commit is

  commit ea2c67bb
  Author: Matt Roper <matthew.d.roper@intel.com>
  Date:   Tue Dec 23 10:41:52 2014 -0800

      drm/i915: Move to atomic plane helpers (v9)

- drm_plane_helper_disable has special code to handle multiple calls
  in a row - it checks plane->crtc == NULL and bails out. This is to
  match the proper atomic implementation which needs the crtc to get
  at the implied locking context atomic updates always need. See

  commit acf24a39
  Author: Daniel Vetter <daniel.vetter@ffwll.ch>
  Date:   Tue Jul 29 15:33:05 2014 +0200

      drm/plane-helper: transitional atomic plane helpers

- The universal plane code split out the implicit primary plane from
  the CRTC into it's own full-blown drm_plane object. As part of that
  the setcrtc ioctl (which updated both the crtc mode and primary
  plane) learned to set crtc->primary->crtc on modeset to make sure
  the plane->crtc assignments statate up to date in

  commit e13161af
  Author: Matt Roper <matthew.d.roper@intel.com>
  Date:   Tue Apr 1 15:22:38 2014 -0700

      drm: Add drm_crtc_init_with_planes() (v2)

  Unfortunately we've forgotten to update the load detect code. Which
  wasn't a problem since the load detect modeset is temporary and
  always undone before we drop the locks.

- Finally there is a organically grown history (i.e. don't ask) around
  who sets the legacy plane->fb for the various driver entry points.
  Originally updating that was the drivers duty, but for almost all
  places we've moved that (plus updating the refcounts) into the core.
  Again the exception is the load detect code.

Taking all together the following happens:
- The load detect code doesn't set crtc->primary->crtc. This is only
  really an issue on crtcs never before used or when userspace
  explicitly disabled the primary plane.

- The plane helper glue code short-circuits because of that and leaves
  a non-NULL fb behind in plane->state->fb and plane->fb. The state
  fb isn't a real problem (it's properly refcounted on its own), it's
  just the canary.

- Load detect code drops the reference for that fb, but doesn't set
  plane->fb = NULL. This is ok since it's still living in that old
  world where drivers had to clear the pointer but the core/callers
  handled the refcounting.

- On the next modeset the drm core notices plane->fb and takes care of
  refcounting it properly by doing another unref. This drops the
  refcount to zero, leaving state->plane now pointing at freed memory.

- intel_plane_duplicate_state still assume it owns a reference to that
  very state->fb and bad things start to happen.

Fix this all by applying the same duct-tape as for the legacy setcrtc
ioctl code and set crtc->primary->crtc properly.

Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Paul Bolle <pebolle@tiscali.nl>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Paulo Zanoni <przanoni@gmail.com>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: Matt Roper <matthew.d.roper@intel.com>
Reported-and-tested-by: NLinus Torvalds <torvalds@linux-foundation.org>
Reported-by: NPaul Bolle <pebolle@tiscali.nl>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

By this patch all underlying bits have been implemented and this
patch actually enables the feature.

v2: Validate passed in fb modifiers to reject garbage. (Daniel Vetter)
v3: Rearrange validation checks per code review comments. (Daniel Vetter)
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com> (v1)
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Display watermarks need different programming for different tiling
modes.

Set the relevant flag so this happens during the plane commit and
add relevant data into a structure made available to the watermark
computation code.

v2: Pass in tiling info to sprite plane updates as well.
v3: Rebased for plane handling changes.
v4: Handle fb == NULL when plane is disabled.
v5: Refactored for addfb2 interface.
v6: Refactored for fb modifier changes.
v7: Updated for atomic commit by only updating watermarks when tiling changes.
v8: BSpec watermark calculation updates.
v9: Restrict scope of y_tile_minimum variable. (Damien Lespiau)
v10: Get fb from plane state otherwise we are working on old state.
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Acked-by: NAnder Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Acked-by: NMatt Roper <matthew.d.roper@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com> (v9)
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

v2: Rebased for addfb2 interface and consolidated a bit. (Tvrtko Ursulin)
v3: Rebased for fb modifier changes. (Tvrtko Ursulin)
v4: Use intel_fb_stride_alignment instead of open coding. (Damien Lespiau)
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

1Mb!

v2: Rebased for addfb2 interface. (Tvrtko Ursulin)
v3: Rebased for fb modifier changes. (Tvrtko Ursulin)
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We now need the bpp of the fb as Yf tiling has different tile widths
depending on it.

v2: Rebased for the new addfb2 interface. (Tvrtko Ursulin)
v3: Rebased for fb modifier changes. (Tvrtko Ursulin)
v4: Added missing case and 128-bit pixel warning. (Damien Lespiau)
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com> (v3)
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Skylake is able to scannout those tiling formats. We need to allow them
in the ADDFB ioctl and tell the harware about it.

v2: Rebased for addfb2 interface. (Tvrtko Ursulin)
v3: Rebased for fb modifier changes. (Tvrtko Ursulin)
v4: Don't allow Y tiled fbs just yet. (Tvrtko Ursulin)
v5: Check for stride alignment and max pitch. (Tvrtko Ursulin)
v6: Simplify maximum pitch check. (Ville Syrjälä)
v7: Drop the gen9 check since requirements are no different. (Ville Syrjälä)
v8: Gen2 has different X tiling stride. (Ville Syrjälä)
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com> (v7)
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Mostly just checks in i915-private modeset ioctls.
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>