BSpec says we shouldn't enable FBC on HSW/BDW when the pipe pixel rate
exceeds 95% of the core display clock.

v2:
  - HSW also needs the WA (Ville).
  - Add the WA name (Ville).
  - Use the current cdclk (Ville).
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

And also print the threshold. I was surprised to see a log message
claiming the CFB size was 32mb when there was less than 24mb available
for it.
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

The FBC hardware for these platforms doesn't have access to the
bios_reserved range, so it always assumes the maximum (8mb) is used.
So avoid this range while allocating.

This solves a bunch of FIFO underruns that happen if you end up
putting the CFB in that memory range. On my machine, with 32mb of
stolen, I need a 2560x1440 mode for that.

Testcase: igt/kms_frontbuffer_tracking/fbc-* (given the right setup)
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Don't allow FBC for cases where the spec says we can't FBC.

v2:
  - Just WARN_ON() the strides that should have been caught earlier
    (Daniel)
  - Make it a new function since I expect this to grow more.
v3:
  - Document which IGT test is exercised by this.
v4:
  - Implement the restrictions for gens 2-6 too (Ville).
  - Fix off-by-one mistake (Ville).

Testcase: igt/kms_frontbuffer_tracking/fbc-badstride
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Always update the currrent crtc, fb and vertical offset after calling
enable_fbc. We were forgetting to do so along the failure paths when
enabling fbc synchronously. Fix this with a new helper to enable_fbc()
and update the state simultaneously.

v2: Improve commit message (Chris).
v3: Constify struct drm_framebuffer (Ville).
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

The scaler_id in intel_pipe_config_compare should not be checked
when adjusting in intel_pipe_config_compare. The hw scaler id may
be changed in intel_update_pipe_config.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Cc: Alex Dai <yu.dai@intel.com>
Cc: Tom O'Rourke <Tom.O'Rourke@intel.com>
Cc: Akash Goel <akash.goel@intel.com>
Signed-off-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Reviewed-by: Alex Dai <yu.dai@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Cc: Tom O'Rourke <Tom.O'Rourke@intel.com>
Cc: Akash Goel <akash.goel@intel.com>
Signed-off-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Reviewed-by: Alex Dai <yu.dai@intel.com>
[danvet: Fix continuation alignment.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Enable TO mode for RC6 for SKL till D0 and BXT till A0.

Cc: Tom O'Rourke <Tom.O'Rourke@intel.com>
Cc: Akash Goel <akash.goel@intel.com>
Signed-off-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Reviewed-by: Alex Dai <yu.dai@intel.com>
[danvet: Fixup line continuation alignment.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

WaRsDisableCoarsePowerGating: Coarse Power Gating (CPG) needs to be
disabled for platforms prior to BXT B0 and SKL GT3/GT4 till E0.

v2: Added GT3/GT4 Check.

Change-Id: Ia3c4c16e050c88d3e259f601054875c812d69c3a
Signed-off-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Reviewed-by: Alex Dai <yu.dai@intel.com>
[danvet: Align continuation properly.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

It will be usefull to specify w/a that affects only SKL GT3 and GT4.
Signed-off-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Reviewed-by: Alex Dai <yu.dai@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Looks like this was introduced in:
commit d1675198
Author: Alex Dai <yu.dai@intel.com>
Date:   Wed Aug 12 15:43:43 2015 +0100

    drm/i915: Integrate GuC-based command submission

This patch assumed LRC contexts and HWS layout, which is incorrect on
platforms without execlists.  This can lead to a crash in GPU error
state readout on those platforms.

I don't see a bug filed for this, but there may be one that I haven't
found.

v2: fixup offset handling for error capture fix (Dave)

Cc: Alex Dai <yu.dai@intel.com>
Reviewed-by: Dave Gordon <david.s.gordon@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

intel_modeset_readout_hw_state() seems like the more appropriate place
for populating the scanline_offset and timestamping constants than
intel_sanitize_crtc() since they are basically part of the state we
read out.

Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Move the sprite/cursor plane disabling to occur in intel_sanitize_crtc()
where it belongs instead of doing it in intel_modeset_readout_hw_state().

The plane disabling was first added in
4cf0ebbd drm/i915: Rework plane readout.

I got the idea from some patches from Partik and/or Maarten but those
moved also the plane state readout to intel_sanitize_crtc() which isn't
quite right in my opinion.

Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
References: https://bugs.freedesktop.org/show_bug.cgi?id=91910Reviewed-by: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

The dotclock is often calculated in encoder .get_config(), so we
shouldn't copy the adjusted_mode to hwmode until we have read out the
dotclock.

Gets rid of some warnings like these:
[drm:drm_calc_timestamping_constants [drm]] *ERROR* crtc 21: Can't calculate constants, dotclock = 0!
[drm:i915_get_vblank_timestamp] crtc 0 is disabled

v2: Steal Maarten's idea to move crtc->mode etc. assignment too

Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91428Reviewed-by: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

The Bspec is very clear that Live status must be checked about before
trying to read EDID over DDC channel. This patch makes sure that HDMI
EDID is read only when live status is up.

The live status doesn't seem to perform very consistent across various
platforms when tested with different monitors. The reason behind that is
some monitors are late to provide right voltage to set live_status up.
So, after getting the interrupt, for a small duration, live status reg
fluctuates, and then settles down showing the correct staus.

This is explained here in, in a rough way:
HPD line  ________________
			 |\ T1 = Monitor Hotplug causing IRQ
			 | \______________________________________
			 | |
                         | |
			 | |   T2 = Live status is stable
			 | |  _____________________________________
			 | | /|
Live status _____________|_|/ |
			 | |  |
			 | |  |
			 | |  |
			T0 T1  T2

(Between T1 and T2 Live status fluctuates or can be even low, depending on
 the monitor)

After several experiments, we have concluded that a max delay
of 30ms is enough to allow the live status to settle down with
most of the monitors. This total delay of 30ms has been split into
a resolution of 3 retries of 10ms each, for the better cases.

This delay is kept at 30ms, keeping in consideration that, HDCP compliance
expect the HPD handler to respond a plug out in 100ms, by disabling port.

v2: Adding checks for VLV/CHV as well. Reusing old ibx and g4x functions
to check digital port status. Adding a separate function to get bxt live
status (Daniel)
v3: Using intel_encoder->hpd_pin to check the live status (Siva)
Moving the live status read to intel_hdmi_probe and passing parameter
to read/not to read the edid. (me)
v4:
* Added live status check for all platforms using
intel_digital_port_connected.
* Rebased on top of Jani's DP cleanup series
* Some monitors take time in setting the live status. So retry for few
times if this is a connect HPD
v5: Removed extra "drm/i915" from commit message. Adding Shashank's sob
    which was missed.
v6: Drop the (!detect_edid && !live_status check) check because for DDI
ports which are enumerated as hdmi as well as DP, we don't have a
mechanism to differentiate between DP and hdmi inside the encoder's
hot_plug. This leads to call to the hdmi's hot_plug hook for DP as well
as hdmi which leads to issues during unplug because of the above check.
v7: Make intel_digital_port_connected global in this patch, some
reformatting of while loop, adding a print when live status is not
up. (Rodrigo)
v8: Rebase it on nightly which involved skipping the hot_plug hook for now
and letting the live_status check happen in detect until the hpd handling
part is finalized (Daniel)
Signed-off-by: Shashank Sharma <shashank.sharma@intel.com>
Signed-off-by: Sonika Jindal <sonika.jindal@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

This patch modifies dsi_prepare() function to support the same
modeset prepare sequence for BXT also. Main changes are:
1. BXT port control register is different than VLV.
2. BXT modeset sequence needs vdisplay and hdisplay programmed
   for transcoder.
3. BXT can select PIPE for MIPI transcoders.
4. BXT needs to program register MIPI_INIT_COUNT for both the ports,
   even if only one is being used.

v2: Fixed Jani's review comments. Rectified the DSI Macros to get
    proper register offsets using _MIPI_PORT instead of _TRANSCODER

v3: Rebased on latest drm-nightly branch. Fixed Jani's review comments.
Signed-off-by: Shashank Sharma <shashank.sharma@intel.com>
Signed-off-by: Uma Shankar <uma.shankar@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

This patch adds two new functions:
- disable_dsi_pll.
  BXT DSI disable sequence and registers are
  different from previous platforms.
- intel_disable_dsi_pll
  wrapper function to re-use the same code for
  multiple platforms. It checks platform type and
  calls appropriate core pll disable function.

v2: Fixed Jani's review comments.

v3: Rebased on latest drm-nightly branch.
Signed-off-by: Shashank Sharma <shashank.sharma@intel.com>
Signed-off-by: Uma Shankar <uma.shankar@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

This patch adds new functions for BXT clock and PLL programming.
They are:
1. configure_dsi_pll for BXT.
   This function does the basic math and generates the divider ratio
   based on requested pixclock, and program clock registers.
2. enable_dsi_pll function.
   This function programs the calculated clock values on the PLL.
3. intel_enable_dsi_pll
   Wrapper function to use same code for multiple platforms. It checks the
   platform and calls appropriate core pll enable function.

v2: Fixed Jani's review comments. Macros are adjusted as per convention.

v3: Removed a redundant change wrt code comment.
Signed-off-by: Shashank Sharma <shashank.sharma@intel.com>
Signed-off-by: Uma Shankar <uma.shankar@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

On BXT, We Observe timeout for forcewake request completion with 2ms polling period as given here:
[drm:fw_domains_get] ERROR render: timed out waiting for forcewake ack request.
Polling for 50ms is recommended to avoid these timeouts.

Change-Id: Ie715b0069a3049606e9602bc5e97a6511890864d
Signed-off-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Reviewed by: Alex Dai <yu.dai@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Disable Turbo on steppings prior to B0 on BXT due to hangs seen during GT CPD exit.

Change-Id: I50c5c03f59f5ba092db19e17234951d89db42c6c
Signed-off-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Reviewed by: Alex Dai <yu.dai@intel.com>.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Modified HAS_CSR macro defination which earlier only supported
for skl, now added support for BXT.

v1: Initial version.

v2: Instaed of skylake/broxton check added gen9 check alone based
on review comment from Sunil.

Cc: Vetter, Daniel <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: Animesh Manna <animesh.manna@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Added stepping info in intel_csr.c which is required to extract
specific firmware from packaged dmc firmware.

Stepping info is aligned with current bspec info.

Cc: Vetter, Daniel <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: Animesh Manna <animesh.manna@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Broxton also has dmc to manage low-power display engine state.
Path of the firmware added in intel_csr.c.

Naming convention followed as <platform>_dmc_<api-version>.bin

v1: Initial version.

v2: Commit description added based on review comment from Sunil.

Cc: Damien Lespiau <damien.lespiau@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Sunil Kamath <sunil.kamath@intel.com>
Signed-off-by: Animesh Manna <animesh.manna@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Clearing the watermarks for all pipes/planes when updating the
watermarks for a single CRTC change seems like the wrong thing to
do here. As is, this code will ony update any pipe/plane watermarks
that need updating and leave the remaining set to zero.  Later, the
watermark checks in check_wm_state() will flag these zero'd out pipe/plane
watermarks and throw errors.

By clearing only the watermark values associated with the specific crtc
the other watermark values may remain unchanged.

v2: Make sure all the dirty flags are cleared. Damien
    Clear all values assoicated with crtc/pipe being updated.  Damien
Signed-off-by: Bob Paauwe <bob.j.paauwe@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

We don't want random people to touch these.

Especially true since we've just screwed up SKL by holding it way too
long under the preliminary flag because of some ABI issues. And now
there's howtos all over the internets about how to set this. Same
pretty much for anything else.

Cc: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
[danvet: drop fastboot changes, that option is gone.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

The function can return negative value.

The problem has been detected using proposed semantic patch
scripts/coccinelle/tests/unsigned_lesser_than_zero.cocci [1].

[1]: http://permalink.gmane.org/gmane.linux.kernel/2038576Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Currently everyone and their dog has their own favourite spelling
for vga_switcheroo. This makes it hard to grep dmesg for log entries
relating to vga_switcheroo. It also makes it hard to find related
source files in the tree.

vga_switcheroo.c uses pr_fmt "vga_switcheroo". Use that everywhere.
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Pull in patches Jani merged while I was at XDC.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>

SKL port E handling was added in

commit 26951caf
Author: Xiong Zhang <xiong.y.zhang@intel.com>
Date:   Mon Aug 17 15:55:50 2015 +0800

    drm/i915/skl: enable DDI-E hotplug

but the whole function was moved in a another branch in

commit b93433cc
Author: Jani Nikula <jani.nikula@intel.com>
Date:   Thu Aug 20 10:47:36 2015 +0300

    drm/i915: move ibx_digital_port_connected to intel_dp.c

and the addition was lost at some backmerge that I was unable to
identify. Put it back in.
Tested-by: Tomi Sarvela <tomix.p.sarvela@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

Not the first time! not the last time?

There is a possibility to use gcc 5's -Wbool-compare to try and compare
(reg) in those macros to a constant and gcc will warn that the
comparison between a boolean expression and a constant is always either
true or false. Maybe.

Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

We allocate memory for LVDS modes while parsing the VBT at startup, but
never free this memory when the driver is unloaded, causing a small
leak.
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

Use the new debug info in the intel_crtc struct in these functions
rather than passing them as args.

v2: move min/max assignment back above first trace call (Ville)
    use scanline from crtc->debug rather than fetching a new one (Ville)
v3: fix up trace_i915_pipe_update_end, needs end scanline (Ville)
Requested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

I used these additional fields to track down the issue I saw on HSW.

v2: move debug fields into a substruct (Ville)
v3: clean up debug code more (Ville)

References: https://bugs.freedesktop.org/show_bug.cgi?id=91579Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

Fix the following 'make htmldocs' warnings:

  .//drivers/gpu/drm/i915/i915_gem.c:1729: warning: No description found for parameter 'vma'
  .//drivers/gpu/drm/i915/i915_gem.c:1729: warning: No description found for parameter 'vmf'

  .//drivers/gpu/drm/i915/i915_gem.c:4962: warning: No description found for parameter 'old'
  .//drivers/gpu/drm/i915/i915_gem.c:4962: warning: No description found for parameter 'new'
  .//drivers/gpu/drm/i915/i915_gem.c:4962: warning: No description found for parameter 'frontbuffer_bits'
Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

Shared frontbuffer bits are causing warnings when same FB is displayed
in another plane without clearing the bits from previous plane.

v2: Removing coversion of fb bits to 64 bit as it is not needed for now. (Daniel)

Change-Id: Ic2df80747f314b82afd22f8326297c57d1e652c6
Signed-off-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Signed-off-by: Kumar, Mahesh <mahesh1.kumar@intel.com>
[danvet: Drop INTEL_FRONTBUFFER_SPRITE_MASK since unused.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

WaDisableSTUnitPowerOptimization:skl,bxt
Signed-off-by: Robert Beckett <robert.beckett@intel.com>
Signed-off-by: Arun Siluvery <arun.siluvery@linux.intel.com>
Reviewed-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

This stolen reserved stuff was introduced on g4x, so no need to waste
stolen on older platforms. Unfortunately configdb is no more so I can't
look up the right way to detect this stuff. I do have one hint as to
where the register might be on ctg, but I don't have a ctg to test it,
and on the elk I have here it doesn't contain sensible looking data.
For ilk grits suggegsts it might be in the same place as on snb (the
original PCI reg, not the mirror) but I can't be entirely sure about it
The register shows a round zero on my ilk.

So when there's no really good data for any of these platforms leave the
current "assume 1MiB" approach in place.

Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

This patch fix following warnings while "make xmldocs".
.//drivers/gpu/drm/i915/intel_lrc.c:780: warning: No description
found for parameter 'req'
.//drivers/gpu/drm/i915/intel_lrc.c:780: warning: Excess function
 parameter 'request' description in 'intel_logical_ring_begin'
.//drivers/gpu/drm/i915/intel_lrc.c:780: warning: Excess function
 parameter 'ctx' description in 'intel_logical_ring_begin'
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Extend init/init_hw split to context init.
   - Move context initialisation in to i915_gem_init_hw
   - Move one off initialisation for render ring to
        i915_gem_validate_context
   - Move default context initialisation to logical_ring_init

Rename intel_lr_context_deferred_create to
intel_lr_context_deferred_alloc, to reflect reduced functionality &
alloc/init split.

This patch is intended to split out the allocation of resources &
initialisation to allow easier reuse of code for resume/gpu reset.

v2: Removed function ptr wrapping of do_switch_context (Daniel Vetter)
    Left ->init_context int intel_lr_context_deferred_alloc
    (Daniel Vetter)
    Remove unnecessary init flag & ring type test. (Daniel Vetter)
    Improve commit message (Daniel Vetter)
v3: On init/reinit, set the hw next sequence number to the sw next
    sequence number. This is set to 1 at driver load time. This prevents
    the seqno being reset on reinit (Chris Wilson)
v4: Set seqno back to ~0 - 0x1000 at start-of-day, and increment by 0x100
    on reset.
    This makes it obvious which bbs are which after a reset. (David Gordon
    & John Harrison)
    Rebase.
v5: Rebase. Fixed rebase breakage. Put context pinning in separate
    function. Removed code churn. (Thomas Daniel)
v6: Cleanup up issues introduced in v2 & v5 (Thomas Daniel)

Issue: VIZ-4798
Signed-off-by: Nick Hoath <nicholas.hoath@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: John Harrison <john.c.harrison@intel.com>
Cc: David Gordon <david.s.gordon@intel.com>
Cc: Thomas Daniel <thomas.daniel@intel.com>
Reviewed-by: Thomas Daniel <thomas.daniel@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>