This patch contains the changes to remove the byte
swapping logic introduced with old dmc firmware.
While debugging PC10 entry issue for skylake found
with latest dmc firmware version 1.18 without byte
swapping dmc is working fine and able to enter PC10.

Note that apparently this was changed with dmc version 1.0 and earlier
ones indeed are byteswapped like this ...

v1: Initial version.

v2: Corrected firmware size during memcpy(). (Suggested by Sunil)

Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Damien Lespiau <damien.lespiau@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Sunil Kamath <sunil.kamath@intel.com>
Signed-off-by: NAnimesh Manna <animesh.manna@intel.com>
Signed-off-by: NVathsala Nagaraju <vathsala.nagaraju@intel.com>
Reviewed-by: NA.Sunil Kamath <sunil.kamath@intel.com>
[danvet: Add note that this only holds for released dmc firmware.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

BPP bits defined in VBT should be used only on panels whose
edid version is 1.3 or older. EDID version 1.4 introduced offsets
where bpp is defined and read into display_info, hence bpp from
VBT will be used only when bpc in display_info is zero.

v2: use display_info.bpc for deciding when to use vbt_bpp (Jani)
Signed-off-by: NSivakumar Thulasimani <sivakumar.thulasimani@intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

I was told that the "repurposed D1 definition" is still valid for SKL.
It is BDW that is special due to its hotplug bug, so let's
special-case BDW instead of HSW.

Cc: Kristen Carlson Accardi <kristen@linux.intel.com>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Similar to the ->enable vfunc in patch "drm/i915: Extract a
intel_power_well_enable() function".

v2 (from Paulo):
  - Same s/i915_/intel_/ bikeshed as the previous patch.
  - Update the commit hash.
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We need a bit book keeping around power wells' ops->enable(), namely a
nice debug message and updating hw_enabled. Let's introduce a
intel_power_well_enable() function to make sure all the callers do the
same things.

v2 (from Paulo):
  - s/i915_power_well_enable/intel_power_well_enable/ since everything
    else on this file uses intel_ instead of i915_.
  - Fix typo in commit message.
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

With this simple git diff command one can see that skl_init_workarounds()
got two copies of WaBarrierPerformanceFixDisable:skl:

 git diff -U21 ca6e4405^1 ca6e4405 drivers/gpu/drm/i915/intel_ringbuffer.c

This happened when the backmerge of drm-intel-fixes-2015-07-15
Merged the same fix on both sides. Same fix but not identical enough for
git: with a different surrounding context; hence the code duplication.

This commit merely reverts the output of the git command above
 = the duplication introduced in the backmerge.

(This duplication was found while running git sanity checks on a
_linearized_ i915 forklift for ChromeOS.)
Signed-off-by: NMarc Herbert <marc.herbert@intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Since active function on VLV immediately activate PSR let's give more
time for idleness. Different from core platforms where we have idle_frames
count.

Also kms_psr_sink_crc now is automated and always get this:

[drm:intel_enable_pipe] enabling pipe A
[drm:intel_edp_backlight_on]
[drm:intel_panel_enable_backlight] pipe
[drm:intel_panel_enable_backlight] pipe A
[drm:intel_panel_actually_set_backlight] set backlight PWM = 7812

PSR gets enabled somewhere here after backlight.

[drm:intel_get_hpd_pins] hotplug event received, stat 0x00000000, dig 0x0
[drm:vlv_pipe_set_fifo_size] Pipe A FIFO split 511 / 511 / 511
[drm:vlv_update_wm] Setting FIFO watermarks - A: plane=391, cursor=63, sp

PSR gets flushed around here by intel_atomic_commit

[drm:vlv_pipe_set_fifo_size] Pipe A FIFO split 511 / 511 / 511
[drm:vlv_update_wm] Setting FIFO watermarks - A: plane=391, cursor=63, sp
[drm:intel_set_memory_cxsr] memory self-refresh is enabled
[drm:intel_connector_check_state] [CONNECTOR:39:eDP-1]
[drm:check_encoder_state] [ENCODER:30:DAC-30]
[drm:check_encoder_state] [ENCODER:31:TMDS-31]
[drm:check_encoder_state] [ENCODER:36:TMDS-36]
[drm:check_encoder_state] [ENCODER:38:TMDS-38]
[drm:check_crtc_state] [CRTC:21]
[drm:check_crtc_state] [CRTC:26]
[drm:intel_psr_activate [i915]] *ERROR* PSR Active
[drm:intel_get_hpd_pins] hotplug event received, stat 0x00000000, dig 0x
[drm:intel_set_cpu_fifo_underrun_reporting [i915]] *ERROR* pipe A underrun
[drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe A FIFO
Underrun.

It is true that in a product we won't keep disabling and enabling planes so
frequently, but for safeness let's stay conservative.

It is also true that 500ms is an etternity. But PSR is anyway a power saving
feature for idle scenario. So if it is idle feature stays on and 500ms to get
it reanabled is not that insane.

v2: Rebase over intel_psr.c and fix typo.
v3: Revival: Manual tests indicated that this is needed. With a short delay
    there is a huge risk of getting blank screens when planes are being enabled.
v4: Revival 2 with reasonable delay. 1/2 sec instead of 5. VBT is 10 sec but
    actually time for link training what we aren't doing, but with only 100 sec
    in some cases kms_psr_sink_crc manual was showing blank screen,
    so let's use this for now. Also changed comment by a FIXME.
v5: Rebase after a long time, remove FIXME and update comment above.
v6: msecs_to_jiffies is already on delay. remove duplication.
v7: use msecs_to_jiffies on schedule_delayed_work call.

Reviewed-by: Durgadoss R <durgadoss.r@intel.com> (v4)
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Tested-By: Intel Graphics QA PRTS (Patch Regression Test System Contact: shuang.he@intel.com)
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This is just a preparation patch to make clear what operation we
are performing. There is no functional change on the sink crc
logic.

hsw_disable_ips has been moved a bit further in the start function
to avoid disabling ips when sink crc is not going to be started.
and to avoid goto on this function.

v2: explain why hsw_disable_ips() call place has changed.

Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: NRafael Antognolli <rafael.antognolli@intel.com>
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

First, an introduction. We currently have two types of GTT mmaps: the
"normal" old mmap, and the WC mmap. For frontbuffer-related features
that have automatic hardware tracking, only the non-WC mmap writes are
detected by the hardware. Since inside the Kernel both are treated as
ORIGIN_GTT, any features ignoring ORIGIN_GTT because of the hardware
tracking are destined to fail.

One of the special rules defined for the WC mmaps is that the user
should call the dirtyfb IOCTL after he is done using the pointers, so
that results in an intel_fb_obj_flush() call. The problem is that the
dirtyfb is passing ORIGIN_GTT, so it is being ignored by FBC - even
though the hardware tracking is not detecing the WC mmap operations.
So in order to fix that without having to give up the automatic
hardware tracking for GTT mmaps we transform the flush operation from
dirtyfb into a special operation: ORIGIN_DIRTYFB.

This commit fixes all the kms_frontbuffer_tracking subtests that
contain "fbc" and "mmap-wc" in their names and are currently failing
(for a total of 16 subtests).
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Use the appropriate call.

I know there's a discussion about whether we need this call here at
all, but removing the call means we'll only update FBC after we get
the page flip IRQ. So the user may only see the new frame a little
after it should. Let's wait just a little bit more before removing
this call since we can rely in the HW tracking for accurate flips.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Because intel_unpin_work_fn() already calls
intel_frontbuffer_flip_complete() which will call intel_fbc_flush()
which will call intel_fbc_update() when needed.

We couldn't fix this previously due to the fact that FBC was not
properly behaving as intended on frontbuffer flushes, but now that
this is fixed, we can remove the additional call.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Due to the way busy_bits was handled, we were not doing any flushes if
we didn't previously get an invalidate. Since it's possible to get
flushes without an invalidate first, remove the busy_bits early
return.

So now that we don't have the busy_bits guard anymore we'll need the
origin check for the GTT tracking (we were not doing anything on GTT
flushes due to the GTT check at invalidate()).

As a last detail, since we can get multiple consecutive flushes,
disable FBC before updating it, otherwise intel_fbc_update() will just
keep FBC enabled instead of restarting it.

Notice that this does not fix any of the current IGT tests due to the
fact that we still have a few intel_fbc() calls at points where we
also have the frontbuffer tracking calls: we didn't fully convert to
frontbuffer tracking yet. Once we remove those calls and start relying
only on the frontbuffer tracking infrastructure we'll need this patch.
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

As we may like to use a bisection search on the tables in future, we
need them to be ordered. For convenience we expect the compiled tables
to be order and check on initialisation. However, the validator used the
wrong iterators failed to spot the misordered MI tables and instead
walked off into the unknown (as spotted by kasan).
Signed-off-by: NHanno Boeck <hanno@hboeck.de>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
[danvet: Again hand-assemble patch ...]
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>

In the future, we may want to speed up command/register searching using
a bisection and so we require them to be in ascending order respectively
by command value or register address. However, this was not true for one
pair in the MI table; make it so.
Signed-off-by: NHanno Boeck <hanno@hboeck.de>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
[danvet: Hand-assemble patch from raw patch from Hanno and commit message from Chris.]
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>

If we got to the point where we are trying to stop sink CRC
the main output of this function was already gotten properly,
so don't return the error and let userspace use the crc data.

Let's replace the errnos returns with some log messages.
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NRafael Antognolli <rafael.antognolli@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Right now if we face any kind of error sink crc calculation
stays enabled.

So, let's give a shot and try to stop it anyway if it got enabled.
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NRafael Antognolli <rafael.antognolli@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

When we shrink our working sets, we want to avoid stealing pages from
objects that likely to be reused in the near future. We first look at
inactive objects before processing active objects - but what about a
recently active object that is about to be used again. That object's
position in the bound_list is ordered by the time of binding, not the
time of last use, so the most recently used inactive object could well
be at the head of the shrink list. To compensate, give the object a bump
to MRU when it becomes inactive (thus transitioning to the end of the
first pass in shrink lists). Conversely, bumping on inactive makes
bumping on active useless, since when we do have to reap from the active
working set, everything is going to become inactive very quickly and the
order pretty much random - just hope for the best at that point, as once
we start stalling on active objects, we can hope that the rebinding
neatly orders vital objects.
Suggested-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
[danvet: Resolve merge conflict.]
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Remove the leftovers, yay!

AGP for i915 kms died long ago with

commit 3bb6ce66
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Wed Nov 13 22:14:16 2013 +0100

    drm/i915: Kill legeacy AGP for gen3 kms

and with ums now gone to there's really no users any more.

Note that device_is_agp is only called when DRIVER_USE_AGP is set and
since we've unconditionally cleared that since a while there are
really no users left for i915_driver_device_is_agp.
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>

Chris rightfully suggested that documenting fences without documenting
the BO tiling tracking doesn't make much sense, so fix that.

The important bit to stress here (since it lead to some confusion) is
the GEM doesn't really care about tiling. Except for a few select cases
where the kernel needs to manage something that userspace can't take
care of: Namely the limited number of fences and fixing up swizzling,
although we still fail at the later.

v2: Move the low-level tiling/swizzling functions and kerneldoc to
i915_gem_fence.c and leave only the userspace interface here.
Suggested by Chris.

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

It fits more with the low-level fence code, and this move leaves only
the userspace tiling ioctl handling in i915_gem_tiling.c.
Suggested-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>

Afaict intel_irq_fini never existed. No idea how that one came
about.

Note: Chris thinks that an irq_fini would be nice and I agree, but
this is just to remove some ugly from generated docs.
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

v2: Clarify that this is about fence _registers_. Also clarify that
the fence code revokes cpu ptes and not gtt ptes. Both suggested by
Chris.

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

No code changes, just moving all the fence related code into a
separate file (and avoiding a bunch of forward declarations while at
it).
Acked-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>

Sorting became confused and a few new files ended up in strange
places. Also move i915_irq.c to core since with the recent-ish
extraction of i915_gpu_error.c and intel_hotplug.c it's more and more
really just basic irq handling code.

When adding new files please don't put them somewhere randomly.
Acked-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>

This is a requirement for enabling display port HPD support on the port
A HPD pin. This support is to be added by follow-up patches.
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NSonika Jindal <sonika.jindal@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Currently HPD_PORT_A is used as an alias for HPD_NONE to mean that the
given port doesn't support long/short HPD pulse detection. SDVO and CRT
ports are like this and for these ports we only want to know whether an
hot plug event was detected on the corresponding pin. Since at least on
BXT we need long/short pulse detection on PORT A as well (added by the
next patch) remove this aliasing of HPD_PORT_A/HPD_NONE and let the
return value of intel_hpd_pin_to_port() show whether long/short pulse
detection is supported on the passed in pin.

No functional change.

v2:
- rebase on top of -nightly (Daniel)
- make the check for intel_hpd_pin_to_port() return value more readable
  (Sivakumar)
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NSonika Jindal <sonika.jindal@intel.com>
Reviewed-by: NSivakumar Thulasimani <sivakumar.thulasimani@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

These functions are quite similar, so combine them with the use of a new
argument for a function that detects long pulses. This will be also
needed by an upcoming patch adding support for BXT long pulse detection.

No functional change.

v2:
- rebase on top -nightly (Daniel)
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NSonika Jindal <sonika.jindal@intel.com>
Reviewed-by: NSivakumar Thulasimani <sivakumar.thulasimani@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The extra check for connector_type is not required as we are already
checking for connector_type != DRM_MODE_CONNECTOR_DisplayPort.
The check was added by commit eb3394fa ("drm/i915: Add debugfs test
control files for Displayport compliance testing")
Signed-off-by: NSudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

While creating the debugfs file we are setting the inode->i_private to
dev. That same dev is passed to these functions as private of struct
seq_file via single_open(). Moreover single_open is setting
file->private_data->private to dev.
So at this point it can never be NULL.
This check was added by commit eb3394fa ("drm/i915: Add debugfs test
control files for Displayport compliance testing")
Signed-off-by: NSudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The Golden batch carries 3D state at the beginning so that HW starts with
a known state. It is carried as a binary blob which is auto-generated from
source. The idea was it would be easier to maintain and keep the complexity
out of the kernel which makes sense as we don't really touch it. However if
you really need to update it then you need to update generator source and
keep the binary blob in sync with it.

There is a need to patch this in bxt to send one additional command to enable
a feature. A solution was to patch the binary data with some additional
data structures (included as part of auto-generator source) but it was
unnecessarily complicated.

Chris suggested the idea of having a secondary batch and execute two batch
buffers. It has clear advantages as we needn't touch the base golden batch,
can customize secondary/auxiliary batch depending on Gen and can be carried
in the driver with no dependencies.

This patch adds support for this auxiliary batch which is inserted at the
end of golden batch and is completely independent from it. Thanks to Mika
for the preliminary review.

v2: Strictly conform to the batch size requirements to cover Gen2 and
add comments to clarify overflow check in macro (Chris, Mika).

v3: aux_batch_offset was declared as u64, change it to u32 (Chris)
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Armin Reese <armin.c.reese@intel.com>
Signed-off-by: NArun Siluvery <arun.siluvery@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Kunmap the renderstate page on error path.
Reviewed-by: NArun Siluvery <arun.siluvery@linux.intel.com>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

intel_guc_fwif.h contains the subset of the GuC interface that we
will need for submission of commands through the GuC. These MUST
be kept in sync with the definitions used by the GuC firmware, and
updates to this file will (or should) be autogenerated from the
source files used to build the firmware. Editing this file is
therefore not recommended.

i915_guc_reg.h contains definitions of GuC-related hardware:
registers, bitmasks, etc. These should match the BSpec.

v2:
    Files renamed & resliced per review comments by Chris Wilson

v4:
    Added DON'T-EDIT-ME warning [Tom O'Rourke]

Issue: VIZ-4884
Signed-off-by: NAlex Dai <yu.dai@intel.com>
Signed-off-by: NDave Gordon <david.s.gordon@intel.com>
Reviewed-by: NTom O'Rourke <Tom.O'Rourke@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Two new module parameters: "enable_guc_submission" which will turn
on submission of batchbuffers via the GuC (when implemented), and
"guc_log_level" which controls the level of debugging logged by the
GuC and captured by the host.
Signed-off-by: NAlex Dai <yu.dai@intel.com>

v4:
    Mark "enable_guc_submission" unsafe [Daniel Vetter]
Signed-off-by: NDave Gordon <david.s.gordon@intel.com>
Reviewed-by: NTom O'Rourke <Tom.O'Rourke@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

i915_gem_object_create_from_data() is a generic function to save data
from a plain linear buffer in a new pageable gem object that can later
be accessed by the CPU and/or GPU.

We will need this for the microcontroller firmware loading support code.

Derived from i915_gem_object_write(), originally by Alex Dai

v2:
    Change of function: now allocates & fills a new object, rather than
        writing to an existing object
    New name courtesy of Chris Wilson
    Explicit domain-setting and other improvements per review comments
        by Chris Wilson & Daniel Vetter

v4:
    Rebased

Issue: VIZ-4884
Signed-off-by: NAlex Dai <yu.dai@intel.com>
Signed-off-by: NDave Gordon <david.s.gordon@intel.com>
Reviewed-by: NTom O'Rourke <Tom.O'Rourke@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This reverts commit 6adfb1ef.

Ironlake RPS code runs under an irqsave spinlock and hence sleeping
isn't allowed. Not a this long delay while blocking irqs isn't great
at all, but fixing the locking scheme is a lot more involved.

So just revert for now.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reported-by: Nkernel test robot <ying.huang@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>

Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Time to light a candle and remove the preliminary_hw_support flag.
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

on SKL/BXT, the top most plane hardware is shared between the legacy
cursor registers and an actual plane. Daniel and Ville don't want to
expose 2 DRM planes and would rather expose a CURSOR plane that has all
the usual plane properties, and that's a blocker for lifting the
prelimary_hw_support flag.

Unfortunately noone has had the time to finish this yet, but lifting the
prelimary_hw_support flag is long overdue. As an intermediate solution
we can merely not expose the top most plane

Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Fix divide by zero if we end up updating the watermarks
with zero dotclock.

This is a stop gap measure to allow module load in cases
where our state keeping fails.

v2: WARN_ON added (Paulo)

Cc: Paulo Zanoni <przanoni@gmail.com>
Cc: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NDamien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>