We never took the lock ourselves and all callers expect the struct_mutex
to be locked upon return (be it success or error), thereore dropping the
lock along the error paths looks to be a vestigial error from

commit db1b76ca
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Tue Jul 9 16:51:37 2013 +0200

    drm/i915: don't frob mm.suspended when not using ums
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

There's actually no real risk since we already check for stricter
constraints earlier (using UINT_MAX / sizeof (struct
drm_i915_gem_exec_object2) as the limit). But in eb_create we use
signed integers, which steals a factor of 2. Luckily struct
drm_i915_gem_exec_object2 for this to not matter.

Still, be consistent and use unsigned integers.

Similar use unsinged integers when checking for overflows in the
relocation entry processing.

I've also added a new subtests to igt/gem_reloc_overflow to also
test for overflowing args->buffer_count values.

v2: Give the variables again tighter scope to make it clear that the
computation is purely local and doesn't leak out to the 2nd block.
Requested by Chris Wilson.

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>

And the gratious overallocation of crtcs. Seems to go back to the ums
days of yonder ...

We also still need it to make the fbdev emulation happy, but I don't
think there's really a need. Especially since the current fbdev
emulation doesn't actually support cloning.

v2: Use sizeof(*pointer) pattern (Jani).

Cc: Jani Nikula <jani.nikula@linux.intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

No buffer overflows here, but better safe than sorry.

v2:
- Fixup the sizeof conversion, I've missed the pointer deref (Jani).
- Drop the redundant GFP_ZERO, kcalloc alreads memsets (Jani).
- Use kmalloc_array for the execbuf fastpath to avoid the memset
  (Chris). I've opted to leave all other conversions as-is since they
  aren't in a fastpath and dealing with cleared memory instead of
  random garbage is just generally nicer.

Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
[danvet: Drop the contentious kmalloc_array hunk in execbuf.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Done while reviewing all our allocations for fubar. Also a few errant
cases of lacking () for the sizeof operator - just a bit of OCD.

I've left out all the conversions that also should use kcalloc from
this patch  (it's only 2).
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

In

commit 81e49f81
Author: Glauber Costa <glommer@openvz.org>
Date:   Wed Aug 28 10:18:13 2013 +1000

    i915: bail out earlier when shrinker cannot acquire mutex

SHRINK_STOP was added to tell the core shrinker code to bail out and
go to the next shrinker since the i915 shrinker couldn't acquire
required locks. But the SHRINK_STOP return code was added to the
->count_objects callback and not the ->scan_objects callback as it
should have been, resulting in tons of dmesg noise like

shrink_slab: i915_gem_inactive_scan+0x0/0x9c negative objects to delete nr=-xxxxxxxxx

Fix discusssed with Dave Chinner.

References: http://www.spinics.net/lists/intel-gfx/msg33597.htmlReported-by: NKnut Petersen <Knut_Petersen@t-online.de>
Cc: Knut Petersen <Knut_Petersen@t-online.de>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Glauber Costa <glommer@openvz.org>
Cc: Glauber Costa <glommer@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Acked-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This regression has been introduced in

commit 9f11a9e4
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Thu Jun 13 00:54:58 2013 +0200

    drm/i915: set up PIPECONF explicitly for i9xx/vlv platforms

Ville brough up the idea that this is just the pipe A quirk gone
wrong.

Note that after resume the bios might or might not have enabled pipe A
already.  We have a bit of magic to make sure that on resume we set up
a decent mode for pipe A, but I fear if I just smash pipe A to always
on we'd enable it in a bogus state and hang the hw. Hence the
readback.

v2: Clarify the logic a bit as suggested by Chris. Also amend the
commit message to clarify why we don't unconditionally enable the
pipe.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=66462
References: https://lkml.org/lkml/2013/8/26/238
Cc: Meelis Roos <mroos@ut.ee>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
[danvet: Use |= instead of = as suggested by Chris.]
Cc: stable@vger.kernel.org
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The native TV encoder has it's own flags to adjust sync modes and
enabled interlaced modes which are totally irrelevant for the adjusted
mode. This worked out nicely since the input modes used by both the
load detect code and reported in the ->get_modes callbacks all have no
flags set, and we also don't fill out any of them in the ->get_config
callback.

This changed with the additional sanitation done with

commit 2960bc9c
Author: Imre Deak <imre.deak@intel.com>
Date:   Tue Jul 30 13:36:32 2013 +0300

    drm/i915: make user mode sync polarity setting explicit

sinc now the "no flags at all" state wouldn't fit through core code
any more. So fix this up again by explicitly clearing the flags in the
->compute_config callback.

Aside: We have zero checking in place to make sure that the requested
mode is indeed the right input mode we want for the selected TV mode.
So we'll happily fall over if userspace tries to pull us.  But that's
definitely work for a different patch series. So just add a FIXME
comment for now.
Reported-by: NKnut Petersen <Knut_Petersen@t-online.de>
Cc: Knut Petersen <Knut_Petersen@t-online.de>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: NKnut Petersen <Knut_Petersen@t-online.de>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

There is no clear cut rules or specs for the retry interval, as there
are many factors that affect overall response time. Increase the
interval, and even more so on branch devices which may have limited i2c
bit rates.
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Reference: https://bugs.freedesktop.org/show_bug.cgi?id=60263Tested-by: NNicolas Suzor <nic@suzor.com>
Reviewed-by: NTodd Previte <tprevite@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

In

commit edc3d884
Author: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Date:   Thu May 23 13:55:35 2013 +0300

    drm/i915: avoid big kmallocs on reading error state

we introduce a two-pass mechanism for splitting long strings being
formatted into the error-state. The first pass finds the length, and the
second pass emits the right portion of the string into the accumulation
buffer. Unfortunately we use the same va_list for both passes, resulting
in the second pass reading garbage off the end of the argument list. As
the two passes are only used for boundaries between read() calls, the
corruption is only rarely seen.

This fixes the root cause behind

commit baf27f9b
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Sat Jun 29 23:26:50 2013 +0100

    drm/i915: Break up the large vsnprintf() in print_error_buffers()
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: stable@vger.kernel.org
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

There is plenty of evidence suggesting all of the GM45 based Acer
laptops (including their eMachines and Packard Bell brands) use inverted
backlight PWM. Assume this is really the case, and quirk them all.

The old bugs that were fixed by subsystem device specific quirks:
 * https://bugs.freedesktop.org/show_bug.cgi?id=59628
 * https://bugzilla.kernel.org/show_bug.cgi?id=31522#c35
 * https://bugs.freedesktop.org/show_bug.cgi?id=44156
 * https://bugzilla.kernel.org/show_bug.cgi?id=53881

See also this bug and the plethora of duplicates:
 * https://bugs.launchpad.net/ubuntu/+source/linux/+bug/765438

References: https://bugzilla.kernel.org/show_bug.cgi?id=54171Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The lower layers of sysfs will not allow an "offset" of more than
GEN7_L3LOG_SIZE and also l3_access_valid() caps it a second time.  But
it's a little easier to audit if we don't have to worry that the
subtraction will result in negative values.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The init and resume codepaths want to handel the power well in slightly
different ways, so pull the power well init out from
intel_modeset_init_hw() which gets called in both cases.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

VGA registers/memory live inside the the display power well. Add a power
domain for VGA.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We increase/decrease the power well refcount in several places now, and
all of those places need to do the same thing, so pull that code into
a few small helper functions.

v2: Rename the funcs to __intel_power_well_{get,put}
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Add APIs to get/put power well references for specific purposes.

v2: Split the i915_request change to another patch
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Reorganize the internal i915_request power well handling to use the
reference count just like everyone else. This way all we need to do is
check the reference count and we know whether the power well needs to be
enabled of disabled.

v2: Split he intel_display_power_{get,put} change to another patch.
    Add intel_resume_power_well() to make sure we enable the power
    well on resume
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Make sure we write to IPS before we actually wait.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We currently disable the ERR_INT interrupts while running the IRQ
handler because we fear that if we do an unclaimed register access
from inside the IRQ handler we'll keep triggering the IRQ handler
forever.

The problem is that since we always disable the ERR_INT interrupts at
the IRQ handler, when we get a FIFO underrun we'll always print both
messages:
  - "uncleared fifo underrun on pipe A"
  - "Pipe A FIFO underrun"

Because the "was_enabled" variable from
ivybridge_set_fifo_underrun_reporting will always be false (since we
disable ERR int at the IRQ handler!).

Instead of actually fixing ivybridge_set_fifo_underrun_reporting,
let's just remove the "disable ERR_INT during the IRQ handler" code.
As far as we know we shouldn't really be triggering ERR_INT interrupts
from the IRQ handler, so if we ever get stuck in the endless loop of
interrupts we can git-bisect and revert (and we can even bisect and
revert this patch in case I'm just wrong). As a bonus, our IRQ handler
is now simpler and a few nanoseconds faster.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Byt doesn't have rc6p and rc6pp support and even more important the
the offsets of the residency registers there's something else. So Just
return a constant 0 to avoid upsetting userspace tools like powertop.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
[danvet: Explain a bit in the commit message what's going on.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Disabling it isn't really an option on these platforms, but having it
available for power comparisons is useful.
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We'd only ever used this define to denote whether or not we have the
dynamic parity feature (DPF) and never to determine whether or not L3
exists. Baytrail is a good example of where L3 exists, and not DPF.

This patch provides clarify in the code for future use cases which might
want to actually query whether or not L3 exists.

v2: Add /* DPF == dynamic parity feature */
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

On both Ivybridge and Haswell, row remapping information is saved and
restored with context. This means, we never actually properly supported
the l3 remapping because our sysfs interface is asynchronous (and not
tied to any context), and the known faulty HW would be reused by the
next context to run.

Not that due to the asynchronous nature of the sysfs entry, there is no
point modifying the registers for the existing context. Instead we set a
flag for all contexts to load the correct remapping information on the
next run. Interested clients can use debugfs to determine whether or not
the row has been remapped.

One could propose at this point that we just do the remapping in the
kernel. I guess since we have to maintain the sysfs interface anyway,
I'm not sure how useful it is, and I do like keeping the policy in
userspace; (it wasn't my original decision to make the
interface the way it is, so I'm not attached).

v2: Force a context switch when we have a remap on the next switch.
(Ville)
Don't let userspace use the interface with disabled contexts.

v3: Don't force a context switch, just let it nop
Improper context slice remap initialization, 1<<1 instead of 1<<i, but I
rewrote it to avoid a second round of confusion.
Error print moved to error path (All Ville)
Added a comment on why the slice remap initialization happens.

CC: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

I have implemented this patch before without creating a separate list
(I'm having trouble finding the links, but the messages ids are:
<1364942743-6041-2-git-send-email-ben@bwidawsk.net>
<1365118914-15753-9-git-send-email-ben@bwidawsk.net>)

However, the code is much simpler to just use a list and it makes the
code from the next patch a lot more pretty.

As you'll see in the next patch, the reason for this is to be able to
specify when a context needs to get L3 remapping. More details there.
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Using LRI for setting the remapping registers allows us to stream l3
remapping information. This is necessary to handle per context remaps as
we'll see implemented in an upcoming patch.

Using the ring also means we don't need to frob the DOP clock gating
bits.

v2: Add comment about lack of worry for concurrent register access
(Daniel)
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
[danvet: Bikeshed the comment a bit by doing a s/XXX/Note - there's
nothing to fix.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Certain HSW SKUs have a second bank of L3. This L3 remapping has a
separate register set, and interrupt from the first "slice". A slice is
simply a term to define some subset of the GPU's l3 cache. This patch
implements both the interrupt handler, and ability to communicate with
userspace about this second slice.

v2:  Remove redundant check about non-existent slice.
Change warning about interrupts of unknown slices to WARN_ON_ONCE
Handle the case where we get 2 slice interrupts concurrently, and switch
the tracking of interrupts to be non-destructive (all Ville)
Don't enable/mask the second slice parity interrupt for ivb/vlv (even
though all docs I can find claim it's rsvd) (Ville + Bryan)
Keep BYT excluded from L3 parity

v3: Fix the slice = ffs to be decremented by one (found by Ville). When
I initially did my testing on the series, I was using 1-based slice
counting, so this code was correct. Not sure why my simpler tests that
I've been running since then didn't pick it up sooner.
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Haswell changed the log registers to be WO, so we can no longer read
them to determine the programming (which sucks, see later note). For
now, simply use the cached value, and hope HW doesn't screw us over.

v2: Simplify the logic to avoid an extra !, remove last, and fix the
buffer offset which broke along the rebase (Ville)

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=57441
CC: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NBen Widawsky <ben@bwidawsk.net>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

I always get royally confused how a modeline with all zeros could
possible pass the paranoid pipe config checker. Until I realize again
that we only check the crtc timings. So dump the crtc timings for the
adjusted mode.

This will be even more important for 3D support where the crtc timings
are markedly different from the input modeline if we have
frame-by-frame 3d output enabled.

Cc: Damien Lespiau <damien.lespiau@intel.com>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Ville and I were wondering why his laptop was missing the
intel_backlight sysfs interface. Turns out we never register it when
CONFIG_BACKLIGHT_CLASS_DEVICE=m. This has been broken ever since the
i915 native backlight interface was added.

CC: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

You can't write it using the MCHBAR mirror, the write will just get
dropped.

This should make us BSpec-compliant, but there's no real bug I could
reproduce that is fixed by this patch.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@gmail.com>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
[danvet: Fix spelling mistake in the comment that Damien spotted.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

On HSW enabling a plane on a disabled pipe may hang the entire system.
And there's no good reason for doing it ever, so just don't.

v2: Move the crtc active checks to intel_crtc_cursor_{set,move} to
    avoid confusing people during modeset

Cc: stable@vger.kernel.org
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Tested-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The cursor is disabled before crtc mode set in crtc disable (and we
assert this is the case), and enabled afterwards in crtc enable. Do not
update it in crtc mode set.

On HSW enabling a plane on a disabled pipe may hang the entire system.
And there's no good reason for doing it ever, so just don't.

v2: Add note about HSW hangs - vsyrjala

Cc: stable@vger.kernel.org
Suggested-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Tested-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Sometimes I see the "non asle set request??" message on my Haswell
machine, so I decided to get the spec and see if some bits are missing
from the mask. We do have some bits missing from the mask, so this
patch adds them, and the corresponding code to print "unsupported"
messages just like we do with the other bits we don't support.

But I still see the "non asle set request??" message on my machine :(

Also use the proper ASLC name to indicate the registers we're talking
about.

v2: - Properly set the new FAILED bits
    - Rename the old FAILED bits
    - Print everything we don't support
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This reduces dmesg noise when there's a glitch on the hpd line, or there
are more than one connectors on the same hpd line and only one of them
changes.

While at it, switch to use the friendly status names instead of numbers.
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

So far we control everything and nothing exceeds the current limits,
but (i) we never think about these limits when reviewing patches, (ii)
not all the callers check the return values and (iii) if we ever hit
any of these messages, we'll have to fix the code that added the bad
message.

The current limit for these messages is 20 since we only have 5 data
registers on all the current gens.

The checks inside intel_dp_aux_native_{write,read} are to prevent
buffer overflows. The check inside intel_dp_aux_ch is to prevent
writing past our 5 data registers.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Double wide mode is only available on pipe A, except on GDG where
pipe B is also double wide capable.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Pipe horizontal source size must be even when either LVDS dual channel
mode, DVO ganged mode, or pipe double wide mode is used.

We must round it down since we can never increase the user specified
viewport size.

The actual error from an odd pipe source width looks like a diagonal
shift, like you might get from a bad stride.

v2: s/ganaged/ganged/
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We don't want to try to push the hardware beyond it's capabilities,
so check the pixel clock against the display core clock limit. Do
it for pre-gen4 for now since that's where we alread have the double
wide pixel clock limit check.

Let's assume that when double wide mode is enabled the max
pixel clock limit is also doubled.

FIXME: panel fitter downscaling probably affects the limit on
non-pch platforms too, so we'd need another version of
ilk_pipe_pixel_rate() to figure that out.

FIXME: should check the limits on all platforms. Also sprites
affect the max allowed pixel rate on some platforms, so we need
to eventually tie all the planes and pipes into one check in
the future. But we need plane state pre-compute before that can
happen.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Read the double wide pipe information from hardware in
i9xx_get_pipe_config(), and check it in intel_pipe_config_compare()

For gen4+ double_wide is always false so the comparison can be done
on all platforms.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>