After the latest changes, ibx_irq_preinstall and ibx_irq_uninstall are
the same, so remove one of the copies and rename the other to
ibx_irq_reset (since we're using the "reset" name for things which are
called both at preinstall and uninstall).

v2: - Rebase.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

On the preinstall stage we should just disable all the interrupts, but
we currently enable all the south display interrupts due to the way we
touch SDEIER at the IRQ handlers (note: they are still masked and our
IRQ handler is disabled). Instead of doing that, let's make the
preinstall stage just disable all the south interrupts, and do the
proper interrupt dance/ordering at the postinstall stage, including an
assert to check if everything is behaving as expected.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

After all, we call ibx_irq_preinstall from gen8_irq_preinstall.

v2: - Rebase.
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Just like ibx_irq_preinstall. We'll call this from somewhere else in
the next patch.
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The duplicate was at an _uninstall function, so rename it to
gen5_gt_irq_reset.

v2: - Rebase.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Same as SERR_INT and the other IIR registers: reset on
preinstall/uninstall and WARN for non-zero values at postinstall. This
one also doesn't need double-clear.

v2: - Remove the is_zero assertion (Ben).
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The SERR_INT register is very similar to the other IIR registers, so
let's zero it at preinstall/uninstall and WARN for a non-zero value at
postinstall, just like we do with the other IIR registers. For this
one, there's no need to double-clear since it can't store more than
one interrupt.

v2: - Remove the is_zero assertion (Ben).
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

It should already be masked and disabled and zeroed at the preinstall
and uninstall stages. Also, the current code just writes to IIR once,
and this is not a guarantee that it will be cleared, so it's wrong
anyway.

The whole reason for the paranoia is that we're going to start calling
the IRQ preinstall/postinstall/uninstall from the runtime PM
callbacks, so we need to make sure everything is behaving as expected.

v2: - Change the original DRM_ERROR to WARN and clear IIR in case it's
      not zero (Ben).
    - Improve commit message (Daniel).
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

And the equivalent GEN8_IRQ_INIT_NDX macro. These macros are for the
postinstall functions. The next patch will improve this macro.

v2: - Adjust to the new POSTING_READ scheme (Ben).

Reviewed-by: Ben Widawsky <ben@bwidawsk.net> (v1)
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The IRQ_INIT and IRQ_FINI macros are basically the same thing, with
the exception that IRQ_FINI doesn't properly clear IIR twice and
doesn't have as many POSTING_READs as IRQ_INIT. So rename the INIT
macro to IRQ_RESET and use it everywhere.

v2: - Fix error in the commit message (Chris).
    - Adjust to the new POSTING_READ scheme (Ben).
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

It's the only thing missing, apparently.

v2: - Fix typo (Ben).
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Same as the _INIT macro: the goal is to reuse the GEN8 macros, but
there are still some slight differences.

v2: - Rebase.
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

And rename it to GEN5_IRQ_INIT.

We have discussed doing equivalent changes on July 2013, and I even
sent a patch series for this: "[PATCH 00/15] Unify interrupt register
init/reset". Now that the BDW code was merged, I have one more
argument in favor of these changes.

Here's what really changes with the Gen 5 IRQ init code:
  - We now clear the IIR registers at preinstall (they are also
    cleared at postinstall, but we will change that later).
  - We have an additional POSTING_READ at the IMR register.

v2: - Fix typo in commit message.
    - Add POSTING_READ calls to the macros (Ben, Daniel, Jani).

Reviewed-by: Ben Widawsky <ben@bwidawsk.net> (v1)
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This interrupt gets initialized with a different IER value, so it was
not using the macro. The problem is that we plan to modify the macro
to make it do additional things, and we want the SDE interrupts
updated too. So let's make sure we call the macro, then, after it, we
do the necessary SDE-specific changes.
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The goal is to reuse the GEN8 macros, but a few changes are needed, so
let's make things easier to review.

I could also use these macros on older code, but since I plan to
change how the interrupts are initialized, we'll risk breaking the
older code in the next commits, so I'll leave this out for now.

v2: - Rebase.
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Pull all the gmch platform hotplug interrupt handling into one
function.

v2: Move the IIR check to the caller
    s/drm_i915_private_t/struct drm_i915_private/
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
[danvet: Add posting read comment suggested by Chris.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Extract all this logic into a new helper function
semaphore_wait_to_signaller_ring because:

- The current code has way too much magic.

- The current code doesn't look at bi16, which encodes VECS signallers
  on HSW. Those are just added after the fact, so can't be encoded in
  a neat formula.

- The current logic can't blow up since it limits its value range
  sufficiently, but that's a bit too tricky to rely on in my opinion.
  Especially when we start to add bdw support.

- I'm not a big fan of the explicit ring->semaphore_register list, but
  I think it's more robust to use the same mapping both when
  constructing the semaphore commands and when decoding them.

- Finally add a FIXME comment about lack of broadwell support here,
  like in the earlier ipehr semaphore cmd detection function.

Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
[danvet: Actually drop the untrue claim in the commit message Chris
pointed out.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Currently not an issue since we don't emit sempahores, but better
not forget about those.

As a little prep work extract the ipehr decoding for cleaner control
flow. And apply a bit of polish.

Cc: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Also drop any unnecessary casts. No functional changes.
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This reverts commit 27544369.

Conflicts:
	drivers/gpu/drm/i915/i915_irq.c

The partial application of interrupt masking without regard to other
pathways for adjusting the RPS frequency results in completely disabling
the PM interrupts. This leads to excessive power consumption as the GPU
is kept at max clocks (until the failsafe mechanism fires of explicitly
downclocking the GPU when all requests are idle). Or equally as bad for
the UX, the GPU is kept at minimum clocks and prevented from upclocking
in response to a requirement for more power.

Testcase: pm_rps/blocking
Cc: Deepak S <deepak.s@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NDeepak S <deepak.s@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

As Broadwell has an increased virtual address size, it requires more
than 32 bits to store offsets into its address space. This includes the
debug registers to track the current HEAD of the individual rings, which
may be anywhere within the per-process address spaces. In order to find
the full location, we need to read the high bits from a second register.
We then also need to expand our storage to keep track of the larger
address.

v2: Carefully read the two registers to catch wraparound between
    the reads.
v3: Use a WARN_ON rather than loop indefinitely on an unstable
    register read.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Ben Widawsky <benjamin.widawsky@intel.com>
Cc: Timo Aaltonen <tjaalton@ubuntu.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Reviewed-by: NBen Widawsky <ben@bwidawsk.net>
[danvet: Drop spurious hunk which conflicted.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

When we use different rps events for different platforms or due to wa,
we might end up needing this logic in a lot of places. Instead of
this let's use a variable in dev_priv to track the enabled PM
interrupts.

v2: Initialize pm_rps_events in intel_irq_init() (Ville).
Signed-off-by: NDeepak S <deepak.s@linux.intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
[danvet: Frob the commit message a bit since the English was a bit too
garbled ;-) ]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

There's an entire pile of issues in here:

- Use the main RING_HEAD register, not ACTHD. ACTHD points at the gtt
  offset of the batch buffer when a batch is executed. Semaphores are
  always emitted to the main ring, so we always want to look at that.

- Mask the obtained HEAD pointer with the actual ring size, which is
  much smaller. Together with the above issue this resulted us in
  trying to dereference a pointer way outside of the ring mmio
  mapping. The resulting invalid access in interrupt context
  (hangcheck is executed from timers) lead to a full blown kernel
  panic. The fbcon panic handler then tried to frob our driver harder,
  resulting in a full machine hang at least on my snb here where I've
  stumbled over this.

- Handle ring wrapping correctly and be a bit more explicit about how
  many dwords we're scanning. We probably should also scan more than
  just 4 ...

- Space out some of teh computations for readability.

This reduces hard-hangs on my snb here. Mika and QA both say that it
doesn't completel remove them, but at least for me it's a clear
improvement in stability.

Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
References: https://bugs.freedesktop.org/show_bug.cgi?id=74100Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The names of the struct members for RPS are stupid. Every time I need to
do anything in this code I have to spend a significant amount of time to
remember what it all means. By renaming the variables (and adding the
comments) I hope to clear up the situation. Indeed doing this make some
upcoming patches more readable.

I've avoided ILK because it's possible that the naming used for Ironlake
matches what is in the docs. I believe the ILK power docs were never
published, and I am too lazy to dig them up.

v2: leave rp0, and rp1 in the names. It is useful to have these limits
available at times. min_freq and max_freq (which may be equal to rp0, or
rp1 depending on the platform) represent the actual HW min and max.

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

When other platforms add runtime PM support they will also need to
disable interrupts, so move the variable to the runtime PM struct.

Also notice that the longer-term goal is to completely kill the
regsave struct, and I even have patches for that.

v2: - Rebase.
v3: - Rebase.
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We need to enable interrupt processing before all the modeset
state is set up. But that means we can fall over when we get a pipe
underrun. This shouldn't happen as long as the bios works correctly
but as usual this turns out to be wishful thinking.

So disable error interrupts at irq install time and rely on the
re-enabling code in the modeset functions to take care of this.

Note that due to the SDE interrupt handling race we must
uncondtionally enable all interrupt sources in SDEIER, hence no need
to enable the SERR bit specifically.

On gmch platforms we don't have an explicit enable/mask bit for fifo
underruns. Fixing this up would require a bit of software tracking,
hence is material for a separate patch. To make this possible we need
to switch all gmch platforms to the new pipestat interrupt handling
scheme Imre implemented for vlv, and then also add a safe form of sw
state checking to __cpu_fifo_underrun_reporting_enabled a bit.

v2: Also handle the ilk/snb cpu fifo underrun bits accordingly.
Spotted by Ville.

v3: Also handle the south interrupt underrun bits on ibx. Again
spotted by Ville.
Reported-by: NRob Clark <robdclark@gmail.com>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: stable@vger.kernel.org
Tested-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

The display interrupts changed on BDW, so the current ILK-HSW specific
code in ilk_pipe_in_vblank_locked() doesn't work there. Add the required
bits for BDW, and while at it, change the existing code to use nicer
looking vblank status bit macros.

Also remove the now stale __raw_i915_read16() definition which was
left over from the failed gen2 ISR experiment.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=73962Tested-by: NLu Hua <huax.lu@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

On HSW the scanline counter seems to behave differently depending on
the output type. eDP on port A does what you would expect an the normal
+1 fixup is sufficient to cover it. But on HDMI outputs we seem to need
a +2 fixup. Just assume we always need the +2 fixup and accept the
slight inaccuracy on eDP.

This fixes a regression introduced in:
 commit 8072bfa6
 Author: Ville Syrjälä <ville.syrjala@linux.intel.com>
 Date:   Mon Oct 28 21:22:52 2013 +0200

    drm/radeon: Move the early vblank IRQ fixup to radeon_get_crtc_scanoutpos()

That commit removed the heuristic that tried to fix up the timestamps
for vblank interrupts that fire a bit too early. Since then the vblank
timestamp code would treat some vblank interrupts as spurious since the
scanline counter would indicate that vblank_start wasn't reached yet.
That in turn lead to incorrect vblank event sequence numbers being
reported to userspace, which lead to unsteady framerate in applications
such as XBMC which uses them for timing purposes.

v2: Remember to call ilk_pipe_in_vblank_locked() on HSW too (Mika)

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=75725
Tested-by: bugzilla1@gmx.com
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

Introduced in
commit e0e33f8ff6f0b6d286afc314802be4993341bd47
Author: Imre Deak <imre.deak@intel.com>
Date:   Tue Mar 4 19:23:07 2014 +0200

The impact was luckily minimal, due to the extra check we do against a
software pipestat IRQ mask.

Caught by Fengguang's 0-day tester.

Cc: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Based on an early draft from Jesse.

Add support for powering on/off the dynamic power wells on VLV by
registering its display and dpio dynamic power wells with the power
domain framework.

For now power on all PHY TX lanes regardless of the actual lane
configuration. Later this can be optimized when the PHY side setup
enables only the required lanes. Atm, it enables all lanes in all
cases.

v2:
- undef function local COND macro after its last use (Ville)
- Take dev_priv->irq_lock around the whole sequence of
  intel_set_cpu_fifo_underrun_reporting_nolock() and
  valleyview_disable_display_irqs(). They are short and releasing
  the lock in between only makes proving correctness more difficult.
- sanitize local var names in vlv_power_well_enabled()
v3:
- rebase on latest -nightly
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
[danvet: Resolve conflict due to my changes in the previous patch.
Also throw in an assert_spin_locked for safety. And finally appease
checkpatch.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Needed by the next patch, wanting to set the underrun reporting as part
of a bigger dev_priv->irq_lock'ed sequence.
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
[danvet: Use more customary __ prefix instead of _nolock postfix.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We'll need to disable/re-enable the display-side IRQs when turning
off/on the VLV display power well. Factor out the helper functions
for this. For now keep the display IRQs enabled by default, so the
functionality doesn't change. This will be changed to enable/disable
the IRQs on-demand when adding support for VLV power wells in an
upcoming patch.

v2:
- take the irq spin lock for the whole enable/disable sequence as
  these can be called with interrupts enabled
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>

This is a left-over from

commit b7e634cc
Author: Imre Deak <imre.deak@intel.com>
Date:   Tue Feb 4 21:35:45 2014 +0200

drm/i915: vlv: don't unmask IIR[DISPLAY_PIPE_A/B_VBLANK] interrupt

where we stopped unmasking the vblank IRQs, but left them enabled in the
IER register. Disable them in IER too.

v2:
- remove comment becoming stale after this change (Ville)
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>

Consistency throughout the code base is good and remove some room for
mistakes (as explained in the "drm/i915: Use a pipe variable to cycle
through the pipes" commit)

So, let's replace the for_each_pipe(i) occurences by for_each_pipe(pipe)
when it's reasonable and practical to do so (eg. when there isn't another
pipe variable already).
Suggested-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We capture error state not only when the GPU hangs but also on
other situations as in interrupt errors and in situations where
we can kick things forward without GPU reset. There will be log
entry on most of these cases. But as error state capture might be
only thing we have, if dmesg was not captured. Or as in GEN4 case,
interrupt error can trigger error state capture without log entry,
the exact reason why capture was made is hard to decipher.

v2: Split out the the error code stuff to separate patch (Ben)

References: https://bugs.freedesktop.org/show_bug.cgi?id=74193Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Apparently we've missed a few more than what Fengguang's 0-day tester
recently reported in i915_irq.c ... Makes sparse happy again (ignore
some spurious stuff about ksyms of exported functions).

Cc: kbuild test robot <fengguang.wu@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Just a bit of polish which I hope will help me with massaging some
internal patches to use Imre's reworked pipestat handling:
- Don't check for underrun reporting or enable pipestat interrupts
  twice.
- Frob the comments a bit.
- Do the iir PIPE_EVENT to pipe mapping explicitly with a switch. We
  only have one place which does this, so better to make it explicit.

v2: Ville noticed that I've broken the logic a bit with trying to
avoid checking whether we're interested in a given pipe twice. push
the PIPESTAT read down after we've computed the mask of interesting
bits first to avoid that duplication properly.

v3: Squash in fixups from Imre on irc.

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

Atm we call the handlers for pending pipestat interrupt events even if
they aren't explicitly enabled by i915_enable_pipestat(). This isn't an
issue for events other than the vblank start event, since those are
always enabled anyways. Otoh, we enable the vblank start event
on-demand, so we'll end up calling the vblank handler at times when they
are disabled.

I haven't checked if this causes any real problem, but for consistency
and to remove some overhead we should still fix this by clearing /
handling only the enabled interrupt events. Also this is a dependency
for the upcoming VLV power domain patchset where we need to disable all
the pipestat interrupts whenever the display power well is off.

v2:
- inline the status->enable mask mapping (Ville)
- don't check for invalid PSR bit on platforms other than VLV (Ville)
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
[danvet: Frob conflict due to different merge order.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

At least on VLV we can't get at the pipestat status bits by simply right
shifting the corresponding enable bits. The mapping between enable and
status bits for the sprite0,1 flip done and the PSR events don't follow
this rule, so we need to map them separately.

The PSR enable for pipe A is DPFLIPSTAT[22], but I haven't added support
for this, since there is no user of it atm. Until support is added WARN
if someone tries to enable PSR interrupts, or tries to enable the same
(1 << 6) bit on pipe B, which MBZ.

v2:
- inline the status->enable mask mapping (Ville)
- fix bogus use of status bits in enable mask (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>

There isn't any PSR interrupt enable bit for pipe A, so we couldn't
enable it through the current API. Passing the corresponding status bits
solves this and also makes the mapping between enable and status bits
simpler on VLV (addressed in an upcoming patch).

Except of checking for invalid status bit arguments, no functional
change.

v2: split out the low level parts of i915_enable_pipestat accepting
    separate enabled and status masks, to make the non-standard mapping
    between those masks stand out more (added in the next patch)
    (Jesse,Daniel)
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>