Restore the lost phys status page cleanup.

Fixes the following splat with DMA_API_DEBUG=y:

WARNING: CPU: 0 PID: 21615 at ../lib/dma-debug.c:974 dma_debug_device_change+0x190/0x1f0()
pci 0000:00:02.0: DMA-API: device driver has pending DMA allocations while released from device [count=1]
               One of leaked entries details: [device address=0x0000000023163000] [size=4096 bytes] [mapped with DMA_BIDIRECTIONAL] [mapped as coherent]
Modules linked in: i915(-) i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops drm sha256_generic hmac drbg ctr ccm sch_fq_codel binfmt_misc joydev mousedev arc4 ath5k iTCO_wdt mac80211 smsc_ircc2 ath snd_intel8x0m snd_intel8x0 snd_ac97_codec ac97_bus psmouse snd_pcm input_leds i2c_i801 pcspkr snd_timer cfg80211 snd soundcore i2c_core ehci_pci firewire_ohci ehci_hcd firewire_core lpc_ich 8139too rfkill crc_itu_t mfd_core mii usbcore rng_core intel_agp intel_gtt usb_common agpgart irda crc_ccitt fujitsu_laptop led_class parport_pc video parport evdev backlight
CPU: 0 PID: 21615 Comm: rmmod Tainted: G     U          4.4.0-rc4-mgm-ovl+ #4
Hardware name: FUJITSU SIEMENS LIFEBOOK S6120/FJNB16C, BIOS Version 1.26  05/10/2004
 e31a3de0 e31a3de0 e31a3d9c c128d4bd e31a3dd0 c1045a0c c15e00c4 e31a3dfc
 0000546f c15dfad2 000003ce c12b3740 000003ce c12b3740 00000000 00000001
 f61fb8a0 e31a3de8 c1045a83 00000009 e31a3de0 c15e00c4 e31a3dfc e31a3e4c
Call Trace:
 [<c128d4bd>] dump_stack+0x16/0x19
 [<c1045a0c>] warn_slowpath_common+0x8c/0xd0
 [<c12b3740>] ? dma_debug_device_change+0x190/0x1f0
 [<c12b3740>] ? dma_debug_device_change+0x190/0x1f0
 [<c1045a83>] warn_slowpath_fmt+0x33/0x40
 [<c12b3740>] dma_debug_device_change+0x190/0x1f0
 [<c1065499>] notifier_call_chain+0x59/0x70
 [<c10655af>] __blocking_notifier_call_chain+0x3f/0x80
 [<c106560f>] blocking_notifier_call_chain+0x1f/0x30
 [<c134cfb3>] __device_release_driver+0xc3/0xf0
 [<c134d0d7>] driver_detach+0x97/0xa0
 [<c134c440>] bus_remove_driver+0x40/0x90
 [<c134db18>] driver_unregister+0x28/0x60
 [<c1079e8c>] ? trace_hardirqs_on_caller+0x12c/0x1d0
 [<c12c0618>] pci_unregister_driver+0x18/0x80
 [<f83e96e7>] drm_pci_exit+0x87/0xb0 [drm]
 [<f8b3be2d>] i915_exit+0x1b/0x1ee [i915]
 [<c10b999c>] SyS_delete_module+0x14c/0x210
 [<c1079e8c>] ? trace_hardirqs_on_caller+0x12c/0x1d0
 [<c115a9bd>] ? ____fput+0xd/0x10
 [<c1002014>] do_fast_syscall_32+0xa4/0x450
 [<c149f6fa>] sysenter_past_esp+0x3b/0x5d
---[ end trace c2ecbc77760f10a0 ]---
Mapped at:
 [<c12b3183>] debug_dma_alloc_coherent+0x33/0x90
 [<f83e989c>] drm_pci_alloc+0x18c/0x1e0 [drm]
 [<f8acd59f>] intel_init_ring_buffer+0x2af/0x490 [i915]
 [<f8acd8b0>] intel_init_render_ring_buffer+0x130/0x750 [i915]
 [<f8aaea4e>] i915_gem_init_rings+0x1e/0x110 [i915]

v2: s/BUG_ON/WARN_ON/ since dim doens't like the former anymore

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Fixes: 5c6c6003 ("drm/i915: Remove DRI1 ring accessors and API")
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> (v1)
Link: http://patchwork.freedesktop.org/patch/msgid/1452538112-5331-1-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Move the ddi buffer translation programming to occur from the encoder
.pre_enable() hook, for just the ddi port we are enabling. Previously
we used to reprogram the translations for all ddi ports during
init and during power well enabling.

v2: s/intel_prepare_ddi_buffers/intel_prepare_ddi_buffer/ (Daniel)
    Resolve conflicts due to  dev_priv->atomic_cdclk_freq
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Only DDI A and E support 10 translation entries in DP mode. For the
other ports the tenth entry is reserved for HDMI.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1449597590-6971-9-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Make the ddi buffer programming code a bit more neat by passing
around dev_priv instead of dev.

v2: Resolve conflicts due to KBL
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> (v1)

skl_get_buf_trans_edp() effectively contains another copy of
skl_get_buf_trans_dp(). Remove the duplication and just call
skl_get_buf_trans_dp() from  skl_get_buf_trans_edp().

v2: Resolve conflicts due to KBL
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> (v1)

skl_get_buf_trans_*() don't need the 'ddi_translations' local variable
since all they with is assign and return. Just return the right thing
directly and get rid of the local variable.

v2: Resolve conflicts due to KBL
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> (v1)

Rather than having open coded checks for the DDI A/E configuration,
just store the max supported lane count in intel_digital_port.

We had an open coded check for DDI A, but not for DDI E. So we may
have been vilating the DDI E max lane count.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

DDI A and E share some of the lanes, so check that we have enough
lanes for the purpose we need before registering the encoders.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1449597590-6971-3-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We're supposed to pass the primary DP encoder to intel_ddi_clk_select(),
not the fake MST encoder. Do so.

There's no real bug here though, since intel_ddi_clk_select() only
checks if the encoder type is EDP (which it isn't for either the
primary DP encoder or the fake MST encoder), and it gets the DDI port
via intel_ddi_get_encoder_port() (which knows how to do the
fake->primary->port dance itself).

Fixes: e404ba8d ("drm/i915: Setup DDI clk for MST on SKL")
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1449597590-6971-2-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Same effect for slightly less source code and resulting binary.
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1452521321-4032-2-git-send-email-tvrtko.ursulin@linux.intel.com

Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452006497-28517-1-git-send-email-jani.nikula@intel.com

Make it a bit tidier and safer.
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/cab24a84811ddbae72d8c3a5f59d29f57b1d3aad.1450702954.git.jani.nikula@intel.com

The sequence block has sizes of elements after the operation byte since
sequence block v3. Use it to skip elements we don't support yet.

v2: remove redundant exec_elem[operation_byte] check (Daniel)
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452006408-27688-1-git-send-email-jani.nikula@intel.com

The changes since the sequence block v2 are:

* The whole MIPI bios data block has a separate 32-bit size field since
  v3, stored after the version. This facilitates big sequences.

* The size of the panel specific sequence blocks has grown to 32
  bits. This facilitates big sequences.

* The elements within sequences now have an 8-bit size field following
  the operation byte. This facilitates skipping unknown new operation
  bytes, i.e. forward compatibility.

v2 (of the patch): use DRM_ERROR for unknown operation byte
v3 (of the patch): even more bounds checking (Ville)
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452518102-3154-1-git-send-email-jani.nikula@intel.com

New sequences, new operations within sequences.
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/96335b9fb875f79882d694360bff060251bd2f17.1450702954.git.jani.nikula@intel.com

Don't choke on unknown elements when we do know how to skip them.
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452518948-16469-1-git-send-email-jani.nikula@intel.com

Properly parse the new sequences added in MIPI sequence block v2.
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/cc1551bdfc4392d02413b78179f3a65c786c75ab.1450702954.git.jani.nikula@intel.com

Add parsing of the i2c element, defined in MIPI sequence block v2. Drop
the status operation byte while at it, that does not exist.
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/d8a2998977feee2f5b5ad609aaca787adfb41479.1450702954.git.jani.nikula@intel.com

If we go into suspend with unclaimed access detected,
it would be nice to catch that access on a next suspend path.
So instead of just notifying about it, arm the unclaimed
mmio checks on suspend side.

We want to keep the asymmetry on resume, as if it was
on resume path, it was not driver that is responsible so
no point in arming mmio debugs.

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1452261080-6979-2-git-send-email-mika.kuoppala@intel.com

With commit 8ac3e1bb ("drm/i915: Add non claimed mmio checking
for vlv/chv") we now have chv/vlv support in place for detecting
unclaimed access. Also the perf hit of extra mmio read
is now only suffered if mmio_debug is set.

This allows us to stuff the macro for unclaimed reg
detection inside a generic gen6 register access, as now all
gens using these macros uses also unclaimed debugs, the one
exception being snb. We gain more clean and generic macros
and only downside is that snb will suffer one branch perf hit
without upside.

Note that the hsw write path debug register check now
happens before fifo check, but this should not make
any real difference.

As vlv/chv use the generic gen6 access macros, the consequence
is that they gain the mmio_debug feature.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1452261080-6979-1-git-send-email-mika.kuoppala@intel.com

This fixes a spurious warning from an integer overflow on 64-bits systems.
The function may return MAX_SCHEDULE_TIMEOUT which gets truncated to -1.

Explicitly handling this by casting to lret fixes it.
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reported-and-tested-by: NJoseph Yasi <joe.yasi@gmail.com>
Tested-by: NAndreas Reis <andreas.reis@gmail.com>
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Cc: drm-intel-fixes@lists.freedesktop.org
Fixes: 3c28ff22 ("i915: wait for fence in prepare_plane_fb")
Link: http://patchwork.freedesktop.org/patch/msgid/5666EEC8.2000403@linux.intel.com

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

Extend the same reasoning as in the patch listed below.  It's not an
error for the workaround list to be empty if no workarounds are needed.

    commit 02235808
    Author: Francisco Jerez <currojerez@riseup.net>
    Date:   Wed Oct 7 14:44:01 2015 +0300
        drm/i915: Don't warn if the workaround list is empty.
Signed-off-by: NWayne Boyer <wayne.boyer@intel.com>
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452129330-3484-2-git-send-email-rodrigo.vivi@intel.com

When adding IS_KABYLAKE definition I didn't included the
DC states related because I was planing to include them
with the patch that fixes DMC firmware loading, but I
forgot them.

Meanwhile this runtime pm code changed a lot for
Skylake.

Well, I didn't expect that this would crash the machine
and I just noticed now that Sarah warned me our driver
wasn't working. Thanks Sarah.

Michel had found the main error first and his
fix had better details on the history and got
merged already:

commit 16fbc291
Author: Michel Thierry <michel.thierry@intel.com>
Date:   Wed Jan 6 12:08:36 2016 +0000

    drm/i915/kbl: Enable PW1 and Misc I/O power wells

This one is a follow-up adding the other remaining
missing pieces.

v2: Rebased on top of Michel's patch as explained above.

Cc: Sarah Sharp <sarah.a.sharp@intel.com>
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NMichel Thierry <michel.thierry@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452214179-22361-1-git-send-email-rodrigo.vivi@intel.com

The dsi_rr_formula() function has been unused for almost two years,
since

commit 44d4c6ee
Author: Shobhit Kumar <shobhit.kumar@intel.com>
Date:   Tue Dec 10 12:14:56 2013 +0530

    drm/i915: Compute dsi_clk from pixel clock

citing the reason as pixel clock based calculation being recommended in
the MIPI host controller documentation. Remove the dead code, we can
always bring it back if it's needed.
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452249940-2605-2-git-send-email-jani.nikula@intel.com

Hide away the platform differences in intel_dsi_get_pckl() within
intel_dsi_pll.c. No functional changes.
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452249940-2605-1-git-send-email-jani.nikula@intel.com

Imre mentioned that chv might also have capability to
track unclaimed mmio accesses. Ville added that
both chv and vlv has this capability and he had already
made this way back [1]. Mimic what Ville's patch does
but adapt on top of less frequent mmio accesses by
omitting checking always on reg writes.

This patch is untested as of now.

v2: overflow handling and posting omitted (Ville)

References: [1] http://lists.freedesktop.org/archives/intel-gfx/2013-May/027599.html
Cc: Imre Deak <imre.deak@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450201542-22918-1-git-send-email-mika.kuoppala@intel.com

Remove char* assignments and add branching hint and
also constify the parameters.

This results in a 35 bytes shorter fast path, so author
boldly assumes it helps without doing in-depth assembly
analysis.

v2: use WARN's branching (Chris), commit name (Joonas)

Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450189512-30360-5-git-send-email-mika.kuoppala@intel.com

We have done unclaimed register access check in normal
(mmio_debug=0) mode once per write. This adds probability
of finding the exact sequence where we did the bad access, but
also adds burden to each write.

As we have mmio_debug available for more fine grained analysis,
give up accuracy of detecting correct spot at the first occurrence
by doing the one shot detection and arming of mmio_debug in hangcheck
and in modeset. This removes the write path performance burden.

v2: Remove gratuitous DRM_DEBUG and return value, comments (Chris)

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Paulo Zanoni <przanoni@gmail.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450250808-14864-1-git-send-email-mika.kuoppala@intel.com

If something, the usual suspect being bios, access hw
behind our back, don't let it slide into situation where
normal register access will detect this and spit out
a warn on into dmesg. On some bdw bioses this happens
during igt/bat run always and as there is not much we can
do about it, its better just to detect and flush this
explicitly on resume and only print a debug message.

v2: use DRM_DEBUG_DRIVER (Chris)
v3: s/access/mmio, s/prior/prior to, s/dev/dev_priv

Testcase: igt/pm_rpm/basic-rte
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Paulo Zanoni <przanoni@gmail.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
[Mika: fixed merge conflict]
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450189512-30360-3-git-send-email-mika.kuoppala@intel.com

Currently interrupt code is the only place checking
for the unclaimed register access prior to actual register
macros using the same functionality. Rename the function
and make it return bool so that the possible error message
context is clear in the caller side. The motivation is to allow
usage of unclaimed detection on arbitrary places.

v2: rebase, s/access/mmio, s/dev/dev_priv
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450189512-30360-2-git-send-email-mika.kuoppala@intel.com

Access the unclaimed reg detection register through
one helper which also does cleanup. Note that we now access
the register only if the platform has the actual non claimed
access bit. This prevents reading the register with gens that
doesn't have the register or the unclaimed bit,
when debug_mmio > 0.

Note that we post after clearing the bit. This makes sure
that the next unclaimed write access would get detected
also if it happened right after clearing, and not fold
into the previous detection.

v2: s/unclaimed_reg_access/check_for_unclaimed_mmio (Chris)
    debug log on unclaimed detection on uncore init (Joonas)

v3: remove posting read (Ville)

Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Paulo Zanoni <przanoni@gmail.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450200287-24080-1-git-send-email-mika.kuoppala@intel.com

If head seems stuck and engine in question is rcs,
inspect subunit state transitions from undone to done,
before deciding that this really is a hang instead of limited
progress. Only account the transitions of subunits from
undone to done once, to prevent unstable subunit states
to keep us falsely active.

As this adds one extra steps to hangcheck heuristics,
before hang is declared, it adds 1500ms to to detect hang
for render ring to a total of 7500ms. We could sample
the subunit states on first head stuck condition but
decide not to do so only in order to mimic old behaviour. This
way the check order of promotion from seqno > atchd > instdone
is consistently done.

v2: Deal with unstable done states (Arun)
    Clear instdone progress on head and seqno movement (Chris)
    Report raw and accumulated instdone's in in debugfs (Chris)
    Return HANGCHECK_ACTIVE on undone->done

References: https://bugs.freedesktop.org/show_bug.cgi?id=93029
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Dave Gordon <david.s.gordon@intel.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Arun Siluvery <arun.siluvery@linux.intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448985372-19535-1-git-send-email-mika.kuoppala@intel.com

No functional changes.

That state the obvious and just duplicate the place we
need to change whenever the table is updated. So let's clean it.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452021535-22641-1-git-send-email-rodrigo.vivi@intel.com

When reviewing DDI translation table I noticed few changes we
haven't incorporated yet and it is always good to follow latest
spec.
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452009511-15064-1-git-send-email-rodrigo.vivi@intel.com

When debuging an intermittent corrupted screen I suspected on DDI
translation table and checked we are out of date with the spec.

I'm not sure this will fix my bug yet, but it is always good to follow
the spec.

v2: Ville caught a switched i-boost value. Thanks!

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452021087-21673-1-git-send-email-rodrigo.vivi@intel.com

This fixes reprobing of display connectors on resume.  After some
talking with danvet on IRC, I learned that calling
drm_helper_hpd_irq_event() does actually trigger a full reprobe of each
connector's status. It turns out this is the actual reason reprobing on
resume hasn't been working (this was observed on a T440s):

	- We call hpd_init()
	- We check each connector for a couple of things before marking
	  connector->polled with DRM_CONNECTOR_POLL_HPD, one of which is an
	  active encoder. Of course, a disconnected port won't have an
	  active encoder, so we don't add the flag to any of the
	  connectors.
	- We call drm_helper_hpd_irq_event()
	- drm_helper_irq_event() checks each connector for the
	  DRM_CONNECTOR_POLL_HPD flag. The only one that has it is eDP-1,
	  so we skip reprobing each connector except that one.

In addition, we also now avoid setting connector->polled to
DRM_CONNECTOR_POLL_HPD for MST connectors, since their reprobing is
handled by the mst helpers. This is probably what was originally
intended to happen here.

Changes since V1:
* Use the explanation of the issue as the commit message instead
* Change the title of the commit, since this does more then just stop a
  check for an encoder now
* Add "Fixes" line for the patch that introduced this regression
* Don't enable DRM_CONNECTOR_POLL_HPD for mst connectors

Changes since V2:
* Put patch changelog above Signed-off-by
* Follow Daniel Vetter's suggestion for making the code here a bit more
  legible

Fixes: 0e32b39c ("drm/i915: add DP 1.2 MST support (v0.7)")
Cc: stable@vger.kernel.org
Signed-off-by: NLyude <cpaul@redhat.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452181408-14777-1-git-send-email-cpaul@redhat.comSigned-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This is a useful thing to have around as a function because the mechanism may
change in the future.

There is a net increase in LOC here, and it will continue to be the case on GEN8
and GEN9 - but future GENs may have an alternate mechanism for doing this.
Signed-off-by: NBen Widawsky <benjamin.widawsky@intel.com>
Reviewed-by: NMichel Thierry <michel.thierry@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452018609-10142-4-git-send-email-benjamin.widawsky@intel.comSigned-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

There is no point in emitting a WARN since the backtrace will always be the
same. Errors have actually become easier to spot given the large number of WARNs
which exist today in modesetting paths.
Signed-off-by: NBen Widawsky <benjamin.widawsky@intel.com>
Reviewed-by: NMichel Thierry <michel.thierry@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452018609-10142-3-git-send-email-benjamin.widawsky@intel.comSigned-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

I think this patch is a worthwhile cleanup even if it might look only marginally
useful. It gets more useful in upcoming patches and for handling of future GEN
platforms.

The only non-mechanical part of this is the removal of the extra & operation on
the ring->next_context_status_buffer. This is safe because right above this, we
already did a modulus operation.
Signed-off-by: NBen Widawsky <benjamin.widawsky@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452018609-10142-2-git-send-email-benjamin.widawsky@intel.comReviewed-by: NMichel Thierry <michel.thierry@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>