Nothing the user (nor we) really can do about this, but upsets a nice
quiet boot.

Note that this happens mostly on SDVs where OEMs obviously haven't had
a chance yet to appropriately trim the output list.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=65988Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
[danvet: Amend commit message a bit to clarify a question from Paulo.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Git commit 90797e6d
("drm/i915: create compact dma scatter lists for gem objects") makes
certain assumptions about the under laying DMA API that are not always
correct.

On a ThinkPad X230 with an Intel HD 4000 with Xen during the bootup
I see:

[drm:intel_pipe_set_base] *ERROR* pin & fence failed
[drm:intel_crtc_set_config] *ERROR* failed to set mode on [CRTC:3], err = -28

Bit of debugging traced it down to dma_map_sg failing (in
i915_gem_gtt_prepare_object) as some of the SG entries were huge (3MB).

That unfortunately are sizes that the SWIOTLB is incapable of handling -
the maximum it can handle is a an entry of 512KB of virtual contiguous
memory for its bounce buffer. (See IO_TLB_SEGSIZE).

Previous to the above mention git commit the SG entries were of 4KB, and
the code introduced by above git commit squashed the CPU contiguous PFNs
in one big virtual address provided to DMA API.

This patch is a simple semi-revert - were we emulate the old behavior
if we detect that SWIOTLB is online. If it is not online then we continue
on with the new compact scatter gather mechanism.

An alternative solution would be for the the '.get_pages' and the
i915_gem_gtt_prepare_object to retry with smaller max gap of the
amount of PFNs that can be combined together - but with this issue
discovered during rc7 that might be too risky.
Reported-and-Tested-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
CC: Chris Wilson <chris@chris-wilson.co.uk>
CC: Imre Deak <imre.deak@intel.com>
CC: Daniel Vetter <daniel.vetter@ffwll.ch>
CC: David Airlie <airlied@linux.ie>
CC: <dri-devel@lists.freedesktop.org>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

In some virtualized environments (e.g. XEN), there is irrelevant ISA bridge in
the system. To work reliably, we should scan trhough all the ISA bridge
devices and check for the first match, instead of only checking the first one.
Signed-off-by: NRui Guo <firemeteor@users.sourceforge.net>
[danvet: Fixup conflict with the num_pch_pll removal. And add
subsystem header to the commit message headline.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Because it's the function that destroys the connector, not the
encoder. And we already have intel_dp_encoder_destroy.

This has annoyed me for a long time.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NZoltan Nyul <zoltan.nyul@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We've been ignoring this return value, so print a nice backtrace in
case it's not what we expected.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NZoltan Nyul <zoltan.nyul@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Because calling intel_dp_encoder_destroy inside
intel_edp_init_connector is just wrong. This is the initialization
path, so we should properly unwind all the initialization through the
whole caller stack.

On the intel_dp_encoder_destroy function we do the following:
1 - Call i2c_del_adapter
2 - Call drm_encoder_cleanup
3 - If edp:
3.1 - Cancel panel_vdd_work
3.2 - Call ironlake_panel_vdd_of_sync
4 - Free the encoder

And here is how we unwind each specific step:
1 - We have intel_dp_init_connector -> intel_dp_i2c_init ->
    i2c_dp_aux_add_bus -> i2c_add_adapter, so we call
    i2c_del_dapter at intel_dp_init_connector
2 - Call it in the same function that called drm_encoder_init
3 - Call it in the same function that called INIT_DELAYED_WORK
4 - Free it in the same function that allocated it
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NZoltan Nyul <zoltan.nyul@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Because calling intel_dp_destroy inside intel_edp_init_connector is
just wrong. This is the initialization path, so we should properly
unwind all the initialization through the whole caller stack.

On the intel_dp_destroy function we do the following:
1 - Free edid if it exists
2 - Call intel_panel_fini in case it's eDP
3 - Call drm_sysfs_connector_remove
4 - Call drm_connector_cleanup
5 - Free the connector

And here is how we unwind each specific step:
1 - No need as we still didn't assign anything
2 - No need as we still didn't call intel_panel_init
3 - Call it in the same function that called drm_sysfs_connector_add
4 - Call it in the same function that called drm_connector_init
5 - Free it in the same function that allocated it
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NZoltan Nyul <zoltan.nyul@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

In case we detect a "ghost eDP", intel_edp_init_connector frees both
the connector and encoder and then returns. On Haswell, intel_ddi_init
then tries to use the freed encoder on the HDMI initialization path
since the following commit:

commit 21a8e6a4
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Wed Apr 10 23:28:35 2013 +0200
    drm/i915: don't setup hdmi for port D edp in ddi_init

So now on intel_ddi_init we check for the "ghost eDP" case and return
without trying to initialize HDMI. This way we won't try to read the
freed "intel_encoder" struct in the next "if" statement.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NZoltan Nyul <zoltan.nyul@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Because intel_dp_init_connector is too big for my poor little brain.
No functional changes.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NZoltan Nyul <zoltan.nyul@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

By the time we call intel_dp_destroy (which destroys the connector)
the encoder may have been destroyed already, so if we use it we may be
reading some free memory. That happens in drm_mode_config_cleanup()
and also inside intel_dp_init_connector() when we detect a ghost eDP.

I also hope this may solve some random memory bugs.

Reported by kmemcheck.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NZoltan Nyul <zoltan.nyul@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This macro doesn't need a semi-colon.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Now that we have this all nicely abstract into separate functions with
self-documenting names this is pointless. And as Yuly Novikov spotted
in the case of ilk-ivb also wrong since we use the pfit both for lvds
and eDP
Reported-By: NYuly Novikov <ynovikov@chromium.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Acked-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The ring names already have "ring" in it.

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

Just move the lowfreq_avail logic out of the register writing as a
prep step for the next patch, which will coalesce all the pch pll
enabling into one spot.

Note that writing the reduced clock dividers to FP1 in a few more
cases (as this patch ends up doing) isn't really relevant since the
FP1 value only matters when we enable the low lock. Which despite
can only happen if we've actually enabled the reduced dotclock and
furthermore isn't even properly implemented on ilk+: Despite claims to
the contrary in the code switching between frequencies if fully
manual.

v2: Explain matters around the FP1 change to answer a question Damien
raised in his review.
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Nowadays (i.e. with Valleyview) we also have edp on non-PCH_SPLIT
platforms, so just checking for LVDS is not good enough.

Secondly we have full pfit pipe config tracking, so we'll correctly
disable the pfit as part of the initial modeset.

For fastboot we need a bit of work here to correctly kill unsupported
configs (if e.g. the pfit is used on anything else than the built-in
panel). But since that's not yet supported we don't need to worry.
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Again we don't really support different settings, so don't let the
BIOS sneak stuff through.

Since the motivation for this patch series is to ensure we have the
correct gamma table mode selected also add the required write to the
GAMMA_MODE register to select the 8bit legacy table.

And since I find lowercase letters in #defines offensive, also
bikeshed those.
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Same reasons as for the previous patch, just no bug report about
anything going wrong yet: We only support exactly the mode we program,
so don't leave any stale BIOS state behind.

Again this will be fun to properly track for fastboot.
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Dragging random garbage along from the BIOS isn't a good idea, since
we really only support exactly what we've set up.

In the specific case for the bug reporter the BIOS used the 10bit
gamma table, but since we only support an 8bit table the dark colors
ended up all wrong and the light ones all unadjusted.

Note that this has a nice implication for fastboot, it essentially
means that we have quite a bit more state to check and compare before
we can decide whether fastboot is possible.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=65593Reported-and-Tested-by: NThomas Hebb <tommyhebb@gmail.com>
Cc: stable@vger.kernel.org
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

plane->enabled is never set, so this code didn't do anything.

Also drm_fb_helper_restore_fbdev_mode() will now disable all cursors
and sprites for us, so we don't have to bother anymore.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDave Airlie <airlied@gmail.com>

After hang check timer has declared gpu to be hung,
rings are reset. In ring reset, when clearing
request list, do post mortem analysis to find out
the guilty batch buffer.

Select requests for further analysis by inspecting
the completed sequence number which has been updated
into the HWS page. If request was completed, it can't
be related to the hang.

For noncompleted requests mark the batch as guilty
if the ring was not waiting and the ring head was
stuck inside the buffer object or in the flush region
right after the batch. For everything else, mark
them as innocents.

v2: Fixed a typo in commit message (Ville Syrjälä)

v3: - more descriptive function parameters (Chris Wilson)
    - use masked head address when inspecting if request is in ring
    - s/hangcheck.last_action/hangcheck.action
    - added comment about unmasked head hitting batch_obj range
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Acked-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

For guilty batchbuffer analysis later on when rings are reset,
store what state the ring was on when hang was declared.
This helps to weed out the waiting rings from the active ones.
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Acked-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

In order to track down a batch buffer and context which
caused the ring to hang, store reference to bo into the request struct.
Request can also cause gpu to hang after the batch in the flush section
in the ring. To detect this add start of the flush portion offset into the
request.

v2: Included comment about request vs batch_obj lifetimes (Chris Wilson)
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Acked-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Only execbuffer needed all the parameters on i915_add_request().
By putting __i915_add_request behind macro, all current callsites
become cleaner. Following patch will introduce a new parameter
for __i915_add_request. With this patch, only the relevant callsite
will reflect the change making commit smaller and easier to understand.

v2: _i915_add_request as function name (Chris Wilson)

v3: change name __i915_add_request and fix ordering of params (Ben Widawsky)
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Acked-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

To get context hang statistics for specified context,
add i915_gem_context_get_hang_stats().

For arb-robustness, every context needs to have its own
hang statistics tracking. Added function will return
the user specified context statistics or in case of
default context, statistics from drm_i915_file_private.

v2: handle default context inside get_reset_state

v3: return struct pointer instead of passing it in as param
    (Chris Wilson)
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Acked-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

To count context losses, add struct i915_ctx_hang_stats for
both i915_hw_context and drm_i915_file_private.
drm_i915_file_private is used when there is no context.

v2: renamed and cleaned up the struct (Chris Wilson, Ian Romanick)
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Acked-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The specs are a bit unclear whether the per-plane trickle feed disable
control exists on VLV. There is another trickle feed disable control
in the MI_ARB register.

After some experimentation it turns out both the DSPCNTR trickle feed
bits and the MI_ARB bit can be toggled. However the DSPCNTR bits don't
seem to have any effect.

The MI_ARB bit, on the other hand, has a noticable effect. I performed
an experiment where I reduced the FIFO size via DSPARB and observed the
effect of the MI_ARB trickle feed bit on the display.

Using a 1920x1080-60 mode, with MI_ARB=0x4 the display started to have
problems with DSPARB=0x42424242, whereas with MI_ARB=0x0 the problems
didn't start until DSPARB=0x09090909. This seems to confirm that the
MI_ARB trickle feed bit actually does work.

So replace the use of the DSPCNTR trickle feed bits with MI_ARB
on VLV.

v2: Amend commit message with results from experimentation
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We have a nice comment saying that the pixel multiplier only sticks
once the vco is on and stable. The only problem is that the enable bit
wasn't set at all. This patch fixes this and so brings the ilk+ pch
pll code in line with the i8xx/i9xx pll code. Or at least improves
matters a lot.

This should fix sdvo on ilk-ivb for low-res modes.
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Just the plumbing, all the modeset and enable code has not yet been
switched over to use the new state. It seems to be decently broken
anyway, at least wrt to handling of the special pixel mutliplier
enabling sequence. Follow-up patches will clean up that mess.

Another missing piece is more careful handling (and fixup) of the fp1
alternate divisor state. The BIOS most likely doesn't bother to
program that one to what we expect. So we need to be more careful with
comparing that state, both for cross checking but also when checking
for dpll sharing when acquiring shared dpll. Otherwise fastboot will
deny a few shared dpll configurations which would otherwise work.

v2: We need to memcpy the pipe config dpll hw state into the pll, for
otherwise the cross-check code will get angry.

v3: Don't forget to read the pch pll state in the crtc get_pipe_config
function for ibx/ilk platforms.
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Now that we have proper hw state reconstruction we should never have a
case where we don't have the software dpll state properly set up. So
add WARNs to the respective !pll cases in enable/disabel_shared_dpll.
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Simply grew too large and needed to be split up into parts.
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Simply grew too big. This also makes the fixup and restore logic in
setup_hw_state stand out a bit more clearly.
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Currently still with an empty register state, this will follow in a
next step. This one here just creates the new vfunc and uses it for
cross-checking, initial state takeover and the dpll assert function.

And add a FIXME for the ddi pll readout code, which still needs to be
converted over.

v2:
- Add some hw state readout debug output.
- Also cross check the enabled crtc counting.

Note that I've botched up the patch ordering, and before this patch
we've read out the pll selection correctly, but did not reconstruct
the refcounts properly. See the bug link.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=65673Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

So don't try to store it in the DPLL_FP register.

Otherwise it looks like the limits for pineview are correct: It has
it's own clock computation code, which doesn't use an offset for n
divisors, and the register value based m limits look sane enough.

v2: Rebase on top of the pineview clock refactor and fixup up the
commit message: It's m1 pnv doens't care about, not m2!

Quoting Damien's review:

  - "n can vary between 2 and 6, but we declare the 3-6 as limits.
  - "p1 seems to be able to go up to 9
  - "the m upper limit seems a bit big, but the docs are a bit shy on
    that values for pnv.

"Otherwise, the change itself seems good:"
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We don't (yet) have proper pixel multiplier readout support on pch
split platforms, so the cross check will naturally fail.

v2: Fix spelling in the comment, spotted by Ville.

v3: Since the ordering constraint is pretty tricky between the crtc
get_pipe_config callback and the encoder->get_config callback add a
few comments about it. Prompted by a discussion with Chris Wilson on
irc about why this does work anywhere else than on i915g/gm.
Reported-by: NChris Wilson <chris@chris-wilson.co.uk>
Acked-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Stéphane Marchesin found a bug where the fences were not being restored,
and in particular the fence pin_count was incorrect. Had we had a
warning in place, this bug would have come to light much earlier. Better
late than never?
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Stéphane Marchesin <marcheu@chromium.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This is of no value to the developer reading the report, let alone the
bamboozled user.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Acked-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

If we detect a ring is in a valid wait for another, just let it be.
Eventually it will either begin to progress again, or the entire system
will come grinding to a halt and then hangcheck will fire as soon as the
deadlock is detected.

This error was foretold by Ben in
commit 05407ff8
Author: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Date:   Thu May 30 09:04:29 2013 +0300

    drm/i915: detect hang using per ring hangcheck_score

"If ring B is waiting on ring A via semaphore, and ring A is making
progress, albeit slowly - the hangcheck will fire. The check will
determine that A is moving, however ring B will appear hung because
the ACTHD doesn't move. I honestly can't say if that's actually a
realistic problem to hit it probably implies the timeout value is too
low."

v2: Make sure we don't even incur the KICK cost whilst waiting.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=65394Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

After kicking a ring, it should be free to make progress again and so
should not be accused of being stuck until hangcheck fires once more. In
order to catch a denial-of-service within a batch or across multiple
batches, we still do increment the hangcheck score - just not as
severely so that it takes multiple kicks to fail.

This should address part of Ben's justified criticism of

commit 05407ff8
Author: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Date:   Thu May 30 09:04:29 2013 +0300

    drm/i915: detect hang using per ring hangcheck_score

"There's also another corner case on the kick. If the seqno = 2
(though not stuck), and on the 3rd hangcheck, the ring is stuck, and
we try to kick it... we don't actually try to find out if the kick
helped."

v2: Make sure we catch DoS attempts with batches full of invalid WAITs.
v3: Preserve the ability to detect loops by always charging the ring
    if it is busy on the same request.
v4: Make sure we queue another check if on a new batch

References: https://bugs.freedesktop.org/show_bug.cgi?id=65394Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

When we reset and restart a ring, we also want to clear any existing
hangcheck.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Use drm_get_format_name to print more readable pixel format names
in debug output.

Also unify the debug messages to say "unsupported pixel format",
which better describes what is going on.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDave Airlie <airlied@redhat.com>