VLV apparently gets upset if the PPS for a pipe currently driving an
external DP port gets used for VDD stuff on another eDP port. The DP
port falls over and fails to retrain when this happens, leaving the
user staring at a black screen.

Let's fix it by also tracking which pipe is driving which DP/eDP port.
We'll track this under intel_dp so that we'll share the protection
of the pps_mutex alongside the pps_pipe tracking, since the two
things are intimately related.

I had plans to reduce the protection of pps_mutex to cover only eDP
ports, but with this we can't do that. Well, for for VLV/CHV at least.
For other platforms it should still be possible, which would allow
AUX communication to occur in parallel for multiple DP ports.

v2: Drop stray crap from a comment (Imre)
    Grab pps_mutex when clearing active_pipe
    Fix a typo in the commit message
v3: Make vlv_active_pipe() static

Cc: stable@vger.kernel.org
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1481738423-29738-1-git-send-email-ville.syrjala@linux.intel.com

It's been unfixed since a while and no one is immediately working on
this. And we have the FIXME already. And now also a task in the DP
team's backlog.

Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: stable@vger.kernel.org
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
References: https://lists.freedesktop.org/archives/intel-gfx/2016-July/101951.htmlAcked-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
[danvet: Adjust comment per Ville's feedback.]
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161213195414.28923-1-daniel.vetter@ffwll.ch

Let's switch to use dev_priv instead of dev when calling
intel_find_panel_downclock() function.
Signed-off-by: NMika Kahola <mika.kahola@intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1481616169-16210-3-git-send-email-mika.kahola@intel.com

Let's switch to use private dev_priv instead of dev when detecting
intel panels.
Signed-off-by: NMika Kahola <mika.kahola@intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1481616169-16210-2-git-send-email-mika.kahola@intel.com

This patch does not change anything functionally, just cleans up
the DP compliance related variables and stores them all together
in a separate struct intel_dp_compliance. There is another struct
intel_dp_compliance_data to store all the test data. This makes it easy to
reset the compliance variables through a memset instead of
individual resetting.

v2:
* Removed functional changes for EDID (Jani Nikula)
Reviewed-by: NJani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: NManasi Navare <manasi.d.navare@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwl.ch>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1481329371-16306-1-git-send-email-manasi.d.navare@intel.com

If link training fails, then we need to fallback to lower
link rate first and if link training fails at RBR, then
fallback to lower lane count.
This function finds the next lower link rate/lane count
value after link training failure and limits the max
link_rate and lane_count values to these fallback values.

v7:
* Remove unnecessary intializations and remove redundant
call to intel_dp_common_rates (Jani Nikula)
v6:
* Cap the max link rate and lane count to the max
values obtained during fallback link training (Daniel Vetter)
v5:
* Start the fallback at the lane count value passed not
the max lane count (Jani Nikula)
v4:
* Remove the redundant variable link_train_failed
v3:
* Remove fallback_link_rate_index variable, just obtain
that using the helper intel_dp_link_rate_index (Jani Nikula)
v2:
Squash the patch that returns the link rate index (Jani Nikula)
Acked-by: NTony Cheng <tony.cheng@amd.com>
Acked-by: NHarry Wentland <harry.wentland@amd.com>
Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: NManasi Navare <manasi.d.navare@intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1481252712-12925-1-git-send-email-manasi.d.navare@intel.com

Sink's capabilities are advertised through DPCD registers and get
updated only on hotplug. So they should be computed only once in the
long pulse handler and saved off in intel_dp structure for the use
later. For this reason two new fields max_sink_lane_count and
max_sink_link_bw are added to intel_dp structure.

This also simplifies the fallback link rate/lane count logic
to handle link training failure. In that case, the max_sink_link_bw
and max_sink_lane_count can be reccomputed to match the fallback
values lowering the sink capabilities due to link train failure.

Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: NManasi Navare <manasi.d.navare@intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1480984058-552-3-git-send-email-manasi.d.navare@intel.com

Not validating the mode rate against max. link rate results in not pruning
invalid modes. For e.g, a HBR2 5.4 Gbps 2-lane configuration does not
support 4k@60Hz. But, we do not reject this mode.

So, make use of the helpers in intel_dp to validate mode data rate against
max. link data rate of a configuration.

v3: Renamed local variables again for consistency (Manasi)
v2: Renamed mode data rate local variable to be more explanatory.
Signed-off-by: NDhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1479243546-17189-1-git-send-email-dhinakaran.pandiyan@intel.comSigned-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>

We store DP link rates as link clock frequencies in kHz, just like all
other clock values. But, DP link rates in the DP Spec. are expressed in
Gbps/lane, which seems to have led to some confusion.

E.g., for HBR2
Max. data rate = 5.4 Gbps/lane x 4 lane x 8/10 x 1/8 = 2160000 kBps
where, 8/10 is for channel encoding and 1/8 is for bit to Byte conversion

Using link clock frequency, like we do
Max. data rate = 540000 kHz * 4 lanes = 2160000 kSymbols/s
Because, each symbol has 8 bit of data, this is 2160000 kBps
and there is no need to account for channel encoding here.

But, currently we do 540000 kHz * 4 lanes * (8/10) = 1728000 kBps

Similarly, while computing the required link bandwidth for a mode,
there is a mysterious 1/10 term.
This should simply be pixel_clock kHz * (bpp/8) to give the final result in
kBps

v2: Changed to DIV_ROUND_UP() and comment changes (Ville)
Signed-off-by: NDhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1479160220-17794-1-git-send-email-dhinakaran.pandiyan@intel.comSigned-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>

Geminilake is mostly backwards compatible with broxton, so change most
of the IS_BROXTON() checks to IS_GEN9_LP(). Differences between the
platforms will be implemented in follow-up patches.

v2: Don't reuse broxton's path in intel_update_max_cdclk().
    Don't set plane count as in broxton.

v3: Rebase

v4: Include the check intel_bios_is_port_hpd_inverted().
    Commit message.

v5: Leave i915_dmc_info() out; glk's csr version != bxt's. (Rodrigo)

v6: Rebase.

v7: Convert a few mode IS_BROXTON() occurances in pps, ddi, dsi and pll
    code. (Rodrigo)

v8: Squash a couple of DDI patches with more conversions. (Rodrigo)

Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NAnder Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1480667037-11215-2-git-send-email-ander.conselvan.de.oliveira@intel.com

Pass dev_priv to intel_setup_outputs() and functions called by it, since
those are all intel i915 specific functions. Also, in the majority of
the functions dev_priv is used more often than dev. In the rare cases
where there are a few calls back into drm core, a local dev variable was
added.

v2: Don't convert dev to &dev_priv->drm in intel_dsi_init. (Ville)
Signed-off-by: NAnder Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1479910904-11005-1-git-send-email-ander.conselvan.de.oliveira@intel.com

Some LSPCON adaptors may return an incorrect LSPCON mode right after
waking from DP Sleep state. This is the case at least for the ParadTech
PS175 adaptor, both when waking because of exiting the DP Sleep to
active state, or due to any other AUX CH transfer. We can determine the
current expected mode based on whether the DPCD area is accessible,
since according to the LSPCON spec this area is only accesible
in PCON mode.

This wait will avoid us trying to change the mode, while the current
expected mode hasn't settled yet and start link training before the
adaptor thinks it's in PCON mode after waking from DP Sleep state.

Cc: Shashank Sharma <shashank.sharma@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NShashank Sharma <shashank.sharma@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1479755707-29596-4-git-send-email-imre.deak@intel.com

We need to get to LSPCON in the next patch, so factor out the helper for
it. While at it also remove the redundant GEN9 check.

Cc: Shashank Sharma <shashank.sharma@intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NShashank Sharma <shashank.sharma@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1479755707-29596-3-git-send-email-imre.deak@intel.com

And as usual a little bit of cascaded function prototype changes.
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>

Instead of checking for everything not supporting the limited color
range bit in the DP port register, let's check for the one thing
that does have it (g4x).
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NJim Bride <jim.bride@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1479145447-12907-3-git-send-email-ville.syrjala@linux.intel.com

A small selection of macros which can only accept dev_priv from
now on and a resulting trickle of fixups.

v2: Keep original order. (Ville Syrjala)
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NDavid Weinehall <david.weinehall@linux.intel.com>

A small selection of macros which can only accept dev_priv from
now on and a resulting trickle of fixups.
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NDavid Weinehall <david.weinehall@linux.intel.com>

Once we've determined that the sink is MST capable we never end up
running through the full detect cycle again, despite getting HPDs.
Fix tht by ripping out the incorrect piece of code responsible.

This got broken when I moved the long HPD handling to the ->detect()
hook, but failed to remove the leftover code.

Cc: Ander Conselvan de Oliveira <conselvan2@gmail.com>
Cc: drm-intel-fixes@lists.freedesktop.org
Cc: Rui Tiago Matos <tiagomatos@gmail.com>
Tested-by: NRui Tiago Matos <tiagomatos@gmail.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=98323
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Tested-by: NKirill A. Shutemov <kirill@shutemov.name>
References: https://bugs.freedesktop.org/show_bug.cgi?id=98306
Fixes: 10158116 ("drm/i915: Move long hpd handling into the hotplug work")
Cc: stable@vger.kernel.org
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1477057478-29328-1-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
(cherry picked from commit 1aab956c)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

drm_select_eld requires mode_config.mutex and connection_mutex
because it looks at the connector list and at the legacy encoders.

This is not required, because when we call audio_codec_enable we know
which connector it was called for, so pass the state.

This also removes having to look at crtc->config.

Changes since v1:
- Use intel_crtc->pipe instead of drm_crtc_index. (Ville)
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1478609742-13603-8-git-send-email-maarten.lankhorst@linux.intel.comReviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>

Unify our approach to things by passing around dev_priv instead of dev.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1477946245-14134-9-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NChris Wilson <chris@chris-wilson.co.uk>

Unify our approach to things by passing around dev_priv instead of dev.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1477946245-14134-8-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NChris Wilson <chris@chris-wilson.co.uk>

The VBT provides the platform a way to mix and match the DDI ports vs.
AUX channels. Currently we only trust the VBT for DDI E, which has no
corresponding AUX channel of its own. However it is possible that some
board might use some non-standard DDI vs. AUX port routing even for
the other ports. Perhaps for signal routing reasons or something,
So let's generalize this and trust the VBT for all ports.

For now we'll limit this to DDI platforms, as we trust the VBT a bit
more there anyway when it comes to the DDI ports. I've structured
the code in a way that would allow us to easily expand this to
other platforms as well, by simply filling in the ddi_port_info.

v2: Drop whitespace changes, keep MISSING_CASE() for unknown
    aux ch assignment, include a commit message, include debug
    message during init

Cc: stable@vger.kernel.org
Cc: Maarten Maathuis <madman2003@gmail.com>
Tested-by: NMaarten Maathuis <madman2003@gmail.com>
References: https://bugs.freedesktop.org/show_bug.cgi?id=97877Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1476208368-5710-2-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NJim Bride <jim.bride@linux.intel.com>
(cherry picked from commit 8f7ce038)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

We want to read 3 bytes here, but because the parenthesis are in the
wrong place we instead read:

	sizeof(intel_dp->edp_dpcd) == sizeof(intel_dp->edp_dpcd)

which is one byte.

Fixes: fe5a66f9 ("drm/i915: Read PSR caps/intermediate freqs/etc. only once on eDP")
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: <drm-intel-fixes@lists.freedesktop.org>
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20161013085508.GJ16198@mwanda
(cherry picked from commit f7170e2e)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

These static helper functions are required to be used during
fallback link rate implemnetation so they need to be placed at the top
of the file.

v3:
* Add cleanup to other patch (Mika Kahola)
v2:
* Dont move around functions declared in intel_drv.h (Rodrigo Vivi)

Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Signed-off-by: NManasi Navare <manasi.d.navare@intel.com>
Reviewed-by: NMika Kahola <mika.kahola@intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1477524358-16563-4-git-send-email-manasi.d.navare@intel.com

On my APL the LSPCON firmware resumes in PCON mode as opposed to the
expected LS mode. It also appears to be in a state where AUX DPCD reads
will succeed but return garbage recovering only after a few hundreds of
milliseconds. After the recovery time DPCD reads will result in the
correct values and things will continue to work. If I2C over AUX is
attempted during this recovery time (implying an AUX write transaction)
the firmware won't recover and will stay in this broken state.

As a workaround check if the firmware is in PCON state after resume and
if so wait until the correct DPCD values are returned. For this we
compare the branch descriptor with the one we cached during init time.
If the firmware was in the LS state, we skip the w/a and continue as
before.

v2:
- Use the DP descriptor value cached in intel_dp. (Jani)
- Get to intel_dp using container_of(), instead of a cached ptr.
  (Shashank)
- Use usleep_range() instead of msleep().

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=98353
Cc: Shashank Sharma <shashank.sharma@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1477326811-30431-9-git-send-email-imre.deak@intel.com

As for external DP sink and branch devices read and print the DP
descriptor for eDP and LSPCON devices as well to aid debugging.

v2:
- Split out this change to a separate patch. (Jani)

Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1477326811-30431-7-git-send-email-imre.deak@intel.com

All types of DP devices (eDP, DP sink, DP branch) will fail their probe
if the start of DPCD can't be read. The LSPCON PCON functionality also
depends on accessing this area, so fail the probe if the read fails.

Cc: Shashank Sharma <shashank.sharma@intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1477326811-30431-6-git-send-email-imre.deak@intel.com

Extend the branch/sink descriptor info with the missing device ID
field. While at it also read out all the descriptor registers in one
transfer and make the debug print more compact.

v2: (Jani)
- Cache the descriptor in intel_dp.
- Split out this change into a separate patch.
v3: (Jani)
- Fix return value check of __intel_dp_read_desc().
- Use %pE instead of %s to print the device ID.

Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1477401159-15098-1-git-send-email-imre.deak@intel.com

There are two separate sets of DPCD registers for the DP OUI - as well as
for the device ID and HW/SW revision - based on whether the given DP
device is a branch or a sink. Currently we print both branch and sink
OUIs, for consistency print only the one that corresponds to the
probed device.

v2:
- Split out this change into a separate patch. (Jani)

Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1477326811-30431-4-git-send-email-imre.deak@intel.com

Performing DPCD AUX reads based on debug settings may introduce obscure
bugs in other places that depend on the read being done (or being not
done). To reduce the uncertainty perform the reads unconditionally.

Cc: Mika Kahola <mika.kahola@intel.com>
Suggested-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1477326811-30431-3-git-send-email-imre.deak@intel.com

This check is open-coded in a few places, so it makes sense to simplify
things by having a helper for it similar to the rest of DPCD feature
helpers.

v2: (Jani)
- Move the helper to drm_dp_helper.h.
- Split out this change to a separate patch.

Cc: Jani Nikula <jani.nikula@intel.com>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1477326811-30431-2-git-send-email-imre.deak@intel.com

Once we've determined that the sink is MST capable we never end up
running through the full detect cycle again, despite getting HPDs.
Fix tht by ripping out the incorrect piece of code responsible.

This got broken when I moved the long HPD handling to the ->detect()
hook, but failed to remove the leftover code.

Cc: Ander Conselvan de Oliveira <conselvan2@gmail.com>
Cc: drm-intel-fixes@lists.freedesktop.org
Cc: Rui Tiago Matos <tiagomatos@gmail.com>
Tested-by: NRui Tiago Matos <tiagomatos@gmail.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=98323
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Tested-by: NKirill A. Shutemov <kirill@shutemov.name>
References: https://bugs.freedesktop.org/show_bug.cgi?id=98306
Fixes: 27d4efc5 ("drm/i915: Move long hpd handling into the hotplug work")
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1477057478-29328-1-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NChris Wilson <chris@chris-wilson.co.uk>

This check is open-coded in a few places, so it makes sense to simplify
things by having a helper for it similar to the rest of DPCD feature
helpers.

v2: (Jani)
- Move the helper to drm_dp_helper.h.
- Split out this change to a separate patch.

Cc: Jani Nikula <jani.nikula@intel.com>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1477326811-30431-2-git-send-email-imre.deak@intel.com

Currently it's entirely possible to go through the link training step
without first determining the lane_count, which is silly since we end up
doing a bunch of aux transfers of size = 0, as highlighted by
WARN_ON(!msg->buffer != !msg->size), and can only ever result in a
'failed to update link training' message. This can be observed during
intel_dp_long_pulse where we can do the link training step, but before
we have had a chance to set the link params. To avoid this we add an
extra check for the lane_count in intel_dp_check_link_status, which
should prevent us from doing the link training step prematurely.

v2: add WARN_ON_ONCE and FIXME comment (Ville)

References: https://bugs.freedesktop.org/show_bug.cgi?id=97344
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Mika Kahola <mika.kahola@intel.com>
Signed-off-by: NMatthew Auld <matthew.auld@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1476912593-10019-1-git-send-email-matthew.auld@intel.comSigned-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>

Fix the poorly indented port parameters to the aux ctl and data
reg functions. This was fallout from the s/i915_mmio_reg_t/i915_reg_t/
that happened during the review of commit f0f59a00 ("drm/i915:
Type safe register read/write")
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1476208368-5710-5-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NJim Bride <jim.bride@linux.intel.com>

The VBT provides the platform a way to mix and match the DDI ports vs.
AUX channels. Currently we only trust the VBT for DDI E, which has no
corresponding AUX channel of its own. However it is possible that some
board might use some non-standard DDI vs. AUX port routing even for
the other ports. Perhaps for signal routing reasons or something,
So let's generalize this and trust the VBT for all ports.

For now we'll limit this to DDI platforms, as we trust the VBT a bit
more there anyway when it comes to the DDI ports. I've structured
the code in a way that would allow us to easily expand this to
other platforms as well, by simply filling in the ddi_port_info.

v2: Drop whitespace changes, keep MISSING_CASE() for unknown
    aux ch assignment, include a commit message, include debug
    message during init

Cc: stable@vger.kernel.org
Cc: Maarten Maathuis <madman2003@gmail.com>
Tested-by: NMaarten Maathuis <madman2003@gmail.com>
References: https://bugs.freedesktop.org/show_bug.cgi?id=97877Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1476208368-5710-2-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NJim Bride <jim.bride@linux.intel.com>

As per the software design, we are driving lspcon in
PCON mode. But while resuming from suspend, lspcon can go
in LS mode (which is its default operating mode on power on)

This patch adds a resume function for lspcon, which makes sure
its operating in PCON mode, post resume.

V2: Address review comments from Imre
	- move lspcon_resume call to encoder->reset()
	- use early returns
Signed-off-by: NShashank Sharma <shashank.sharma@intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Acked-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1476455212-27893-6-git-send-email-shashank.sharma@intel.com

DP link retraining causes (spurious?) underruns. We can't really avoid
them, except perhaps by doing a full modeset (which has its own underrun
suppression anyway). So let's just hide them.

MST still has its own logic for retrainin, but a bigger hpd handling
cleanup/unification is needed there anyway, so let's leave that be for now.

References: https://bugs.freedesktop.org/show_bug.cgi?id=98251Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1476464574-32230-3-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NChris Wilson <chris@chris-wilson.co.uk>

Saves 1416 bytes of .rodata strings.

v2: Add parantheses around dev_priv. (Ville Syrjala)
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NDavid Weinehall <david.weinehall@linux.intel.com>
Acked-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: NJani Nikula <jani.nikula@linux.intel.com>
Acked-by: NChris Wilson <chris@chris-wilson.co.uk>
Acked-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1476352990-2504-1-git-send-email-tvrtko.ursulin@linux.intel.com

Saves 944 bytes of .rodata strings and 128 bytes of .text.

v2: Add parantheses around dev_priv. (Ville Syrjala)
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NDavid Weinehall <david.weinehall@linux.intel.com>
Acked-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: NJani Nikula <jani.nikula@linux.intel.com>
Acked-by: NChris Wilson <chris@chris-wilson.co.uk>
Acked-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>