Pull the BDW+ DE pipe interrupt mask frobbing into a central place,
like we have for other platforms.

v2: Fix the kerneldoc (Daniel)
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448294777-13722-4-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

ironlake_{enable,disable}_display_irq() each just call
ilk_update_display_irq() so let's make them static inlines.

While at it s/ironlake/ilk/ to make things shorter, and a bit more
consistent with the ibx functions.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448294777-13722-3-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

No reason why ibx_{enable,disable}_display_interrupt() couldn't be
static inlines instead of cpp macros.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448294777-13722-2-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This reverts

commit 97e5ed11
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Fri Oct 23 10:56:12 2015 +0200

    drm/i915: shut up gen8+ SDE irq dmesg noise

With the proper fix ("drm/i915: fix the SDE irq dmesg warnings
properly") reliably in place, bring back the error message.

Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448462843-32739-2-git-send-email-jani.nikula@intel.com

We had the "The master control interrupt lied (SDE)!" check and error
message in place for a long time without any problems, until

commit aaf5ec2e
Author: Sonika Jindal <sonika.jindal@intel.com>
Date:   Wed Jul 8 17:07:47 2015 +0530

    drm/i915: Handle HPD when it has actually occurred

caused the errors to start happening. This was bisected and reported,
but the error message was silenced in

commit 97e5ed11
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Fri Oct 23 10:56:12 2015 +0200

    drm/i915: shut up gen8+ SDE irq dmesg noise

shooting the messenger while the debugging for why Sonika's commit
triggered the errors was still in progress.

It looks like we need to read and acknowledge the PCH_PORT_HOTPLUG
register even though the hotplug trigger indicates there isn't a hotplug
irq to handle. The PCH doesn't seem to really ack the the interrupt to
the CPU unless we touch the hotplug register.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Sonika Jindal <sonika.jindal@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92084
Fixes: aaf5ec2e ("drm/i915: Handle HPD when it has actually occurred")
[Jani: added a comment and amended the commit message while applying]
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448462843-32739-1-git-send-email-jani.nikula@intel.com

Commit "30c964a6 drm/i915: Detect virtual south bridge" detects and
handles the southbridge emulated by vmware esx.  Add the ich9 south
bridge emulated by 'qemu -M q35'.
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

commit b04c5bd6
Author: Borun Fu <borun.fu@intel.com>
Date:   Sat Jul 12 10:02:27 2014 +0530

    drm/i915: Power gating display wells during i915_pm_suspend

moved for_each_power_domain from intel_display.c to i915_drv.h but we
still have the definition around in intel_display.c, due to a merge
conflict resolution gone wrong in

commit 4dac3edf
Merge: 48777767 e05444be
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Tue Jul 29 20:49:36 2014 +0200

    Merge remote-tracking branch 'airlied/drm-next' into drm-intel-next

Just remove the extra definition left behind.
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448383645-7615-1-git-send-email-jani.nikula@intel.com

On some machines the CRT connector may be fused off. The weird thing
about this setup is that the ADPA register works otherwise normally,
except the enable bit is hardwired to 0. No one knows of any fuse
register that would tell us if this is the case, so the only thing we
can do (apart from a blacklist) is to try and set the enable bit and see
if it sticks. If not, we don't register the connector at all. Obviously
if the bit is already set when loading the driver we can just assume it
works.

I've smoke tested this approach on several machines (GMCH and PCH),
some with actual CRT connectors, some with shadow connectors, and
obviously the machine (IVB) with the fused off connector. So far
I've not seen any ill effects from this probe.

The main benefit is that we can actually run igt on machines with
fused off connectors, without totally upsetting the state checker.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448051741-22771-1-git-send-email-ville.syrjala@linux.intel.comAcked-by: NChris Wilson <chris@chris-wilson.co.uk>

To get a better idea if underruns occurred during crtc disabling,
let's check for them explicitly. This helps in cases where the
error interrupt isn't active, or there is no underrun interrupt
support at all.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448050160-14124-3-git-send-email-ville.syrjala@linux.intel.comReviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We sometimes get a spurious CPU pipe underrun somewhere between
enabling port A and enabling vdd for the panel. Observed on both
ILK and IVB with port A eDP. Suppress FIFO underrun reporting
around the port and vdd enable to avoid the dmesg errors.

Not sure if port D eDP would suffer from the same issue, but assume
that it doesn't until proven differently.

Testcase: igt/kms_setmode
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448050160-14124-2-git-send-email-ville.syrjala@linux.intel.comAcked-by: NChris Wilson <chris@chris-wilson.co.uk>

We still get spurious pipe underruns on ILK/SNB/IVB under two
circumstances when dealing with PCH ports:
* When the pipe has been disabled, but FDI RX/TX is still enabled
* During FDI link training

Both cases seem to happen at least when we do VGA+HDMI cloning
from the same pipe. I don't think I've seen them when not cloning,
but can't be 100% sure.

Disable underrun reporting around those places to eliminate the
dmesg errors.

Testcase: igt/kms_setmode/basic-clone-single-crtc
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448050160-14124-1-git-send-email-ville.syrjala@linux.intel.comAcked-by: NChris Wilson <chris@chris-wilson.co.uk>

It is not a bad idea to disable the PSR feature on Sink
when we are disabling on the Source.

v2: Move dpcd write inside mutex protected area as suggested by Sonika.

Cc: Sonika Jindal <sonika.jindal@intel.com>
Suggested-by: NSonika Jindal <sonika.jindal@intel.com>
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NSonika Jindal <sonika.jindal@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Whenever DMC firmware put the HW into DC State a bunch
of registers including this perf counter is reset to 0.

Even with PSR active and working we could still read
"Performance_Counter: 0" what will misslead people to believe
PSR is broken. For instance on SKL we can only see PC10
residency with screen on if PSR is working properly.
However Performance_Counter was showing 0.

Even if it restored properly on DC6 exit we don't want to
give users the wrong impression that PSR is not working
while we know for sure it is.

So, it is better to remove this counter information while
we don't have a better way to track PSR residency.
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NDurgadoss R <durgadoss.r@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

When we introduced PSR we let LPSP masked allowing us to get PSR
independently from the audio runtime PM. However in one of the
attempts to get PSR enabled by default one user reported one specific
case where he would miss screen updates if scrolling the firefox in a
Gnome environment when i915 runtime pm was enabled. So for
this specific case that (I could never create an i-g-t test case)
we decided to remove the LPSP mask and let HW tracking taking care of
this case. The mask got removed later by my
commit 09108b90 ("drm/i915: PSR: Remove Low Power HW tracking mask.")

So we started depending on audio driver again, what is bad.

With previous commit
"drm/i915: PSR: Let's rely more on frontbuffer tracking."
we transfered the PSR exit responsability totally to SW frontbuffer
tracking. So now can safelly shut off a bit the HW tracking, or
at least this case that makes us to depend on other drivers.

v2: Update commit message since this patch by itself doesn't solve
    the bugzilla entries.

v3: Another attempt to improve commit message.

Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Tested-by: NBrian Norris <briannorris@chromium.org>
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Damien Lespiau damien.lespiau@intel.com
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The ultimate goal here is to remove the dependency we
currently have on audio driver power to get PSR working.
Since with audio driver runtime PM disabled the Hardware tracking
believes graphics is fully active and prevent PSR Entry, or
in other words continuously exit PSR.

So, the idea is to transfer the PSR exit responsability
from the HW tracking to the SW tracking (frontbuffer tracking),
who is really mature right now.

However with LPSP masked out there might be cases where we could
miss exit from HW tracking since it can be relying on this,
like a specific case reported at our mailing list who
user reported he would miss screen updates if scrolling firefox
in a Gnome environment when i915 runtimepm was enabled.

So before masking out LPSP again to make us independent from
the audio driver we need to make sure that all our cases
are coverred from the frontbuffer tracking perspective,
where the flush means invalidate and flush.

Without this patch for HSW, BDW and SKL we just do the
invalidate part when the flush wasn't originated by a page flip
because we were trusting the HW tracking for the flip case.

So let's rely more on frontbuffer tracking and do the
invalidation regardless the origin as expected for all platforms.

v2: Improve commit message as suggested by Paulo.

v3: Another attempt to let commit message more clear.

Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Damien Lespiau damien.lespiau@intel.com
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Commit (89251b17) intended to remove this line and let only one
DP_PSR_EN_CFG set, but it was wrong and this call is now duplicated
at the code.

Also "& ~DP_PSR_MAIN_LINK_ACTIVE" doesn't do anything at all. It
was like that since I introduced this call but probably the idea
was to be informative and make clear statement that we were not using
the link standby. So it is better to remove this one here and let
the code a bit cleaner.

v2: Improve commit message as requested by Paulo.

Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Tested-by: NBrian Norris <briannorris@chromium.org>
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Damien Lespiau damien.lespiau@intel.com
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Commit e9f24d5f
Author: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Date:   Mon Oct 5 13:26:36 2015 +0100

    drm/i915: Clean up associated VMAs on context destruction

Added a warning based on an incorrect assumption that all VMAs
in a VM will be on the inactive list at the point last reference
to a context and VM is dropped.

This is not true because i915_gem_object_retire__read will not
put VMA on the inactive list until all activities on the object
in question (in all VMs) have been retired.

As a consequence, whether or not a context/VM will be destroyed
with its VMAs still on the active list, can depend on completely
unrelated activities using the same object from a different
context or engine.
Signed-off-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92638
Testcase: igt/gem_request_retire/retire-vma-not-inactive
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michel Thierry <michel.thierry@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448025816-25584-1-git-send-email-tvrtko.ursulin@linux.intel.comSigned-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

If we experience a refcounting failure in a power domain/well (unref'ing at
least one too many times), log the name of the offending domain or well.
Signed-off-by: NDaniel Stone <daniels@collabora.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Acked-by: NJani Nikula <jani.nikula@intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448034934-11926-2-git-send-email-daniels@collabora.com

Let us print human-parseable values from the power domain code; upcoming
display code also wants to use it.

This requires moving it out of i915_debugfs.c, as that is only conditionally
compiled.

v2: Move it out of the header.
Signed-off-by: NDaniel Stone <daniels@collabora.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448034934-11926-1-git-send-email-daniels@collabora.com

Now that the known DMC/DC issues are fixed, let's try again and
re-enable the power well support.
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NPatrik Jakobsson <patrik.jakobsson@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1447869230-21416-1-git-send-email-imre.deak@intel.com

During suspend-to-idle we need to keep the DMC firmware active and DC6
enabled, since otherwise we won't reach deep system power states like
PC9/10. The lead for this came from Nivedita who noticed that the
kernel's turbostat tool didn't report any PC9/10 residency change
across an 'echo freeze > /sys/power/state'.
Reported-by: NNivedita Swaminathan <nivedita.swaminathan@intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NPatrik Jakobsson <patrik.jakobsson@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1447860750-18110-1-git-send-email-imre.deak@intel.com

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

There are platforms that don't need the full GMBUS power domain (BXT)
while others do (PCH, VLV/CHV). For optimizing this we would need to add
a new power domain, but it's not clear how much we would benefit given
the short time we hold the reference. So for now let's keep things
simple.

v2:
- fix commit message, PCH won't take any redundant power resource after
this change (Ville)
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
[fix commit message in v2 (Imre)]
Link: http://patchwork.freedesktop.org/patch/msgid/1447959301-1263-2-git-send-email-imre.deak@intel.com

Suggested by Ville.
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1447959301-1263-1-git-send-email-imre.deak@intel.com

Currently if intelfb_create() errors out, it unrefs the bo even though
the fb now owns that reference. (Spotted by Ville Syrjälä.) We should
unref the fb instead of the bo.

However the fb was not necessarily allocated by intelfb_create(),
it could be inherited from BIOS (the fb struct was then allocated by
dev_priv->display.get_initial_plane_config()) and be in active use by
a crtc. In this case we should call drm_framebuffer_remove() instead
of _unreference() to also disable the crtc.

Daniel Vetter suggested that "fbdev teardown code will take care of it.
The correct approach is probably to not unref anything at all".

But if fbdev initialization fails, the fbdev isn't torn down and
occupies memory even though it's unusable. Therefore clobber it in
intel_fbdev_initial_config(). (Currently we ignore a negative return
value there.) The idea is that if fbdev initialization fails, the driver
behaves as if CONFIG_DRM_FBDEV_EMULATION wasn't set. Should X11 manage
to start up without errors, it will at least be able to use the memory
that would otherwise be hogged by the unusable fbdev.

Also, log errors in intelfb_create().

Don't call async_synchronize_full() in intel_fbdev_fini() when called
from intel_fbdev_initial_config() to avoid deadlock.

v2: Instead of calling drm_framebuffer_unreference() (if fb was not
    inherited from BIOS), call intel_fbdev_fini().

v3: Rebase on e00bf696 (drm/i915: Move the fbdev async_schedule()
    into intel_fbdev.c), call async_synchronize_full() conditionally
    instead of moving it into i915_driver_unload().

Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NLukas Wunner <lukas@wunner.de>
Link: http://patchwork.freedesktop.org/patch/msgid/49ce5f0daead24b7598ec78591731046c333c18d.1447938059.git.lukas@wunner.deSigned-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This reverts commit 2e5356da.

It is now redundant as it is already covered in below commit which introduced
the changes to reuse initialization of resources in resume/reset path.

commit e84fe803
Author: Nick Hoath <nicholas.hoath@intel.com>
Date:   Fri Sep 11 12:53:46 2015 +0100

    drm/i915: Split alloc from init for lrc

lrc_setup_hardware_status_page() in the same function gen8_init_common_ring()
takes care of this.

Cc: Nick Hoath <nicholas.hoath@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NArun Siluvery <arun.siluvery@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1447951664-9347-1-git-send-email-arun.siluvery@linux.intel.comSigned-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

intelfb_create() is called once on driver initialization. If it fails,
ifbdev->helper.fbdev, ifbdev->fb or ifbdev->fb->obj may be NULL.

Further up in the call stack, intel_fbdev_initial_config() calls
intel_fbdev_fini() to tear down the ifbdev on failure. This calls
intel_fbdev_destroy() which dereferences ifbdev->fb. Fix the ensuing
oops.

Also check in these functions if ifbdev is not NULL to avoid oops:

i915_gem_framebuffer_info() is called on access to debugfs file
"i915_gem_framebuffer" and dereferences ifbdev, ifbdev->helper.fb
and ifbdev->helper.fb->obj.

intel_connector_add_to_fbdev() / intel_connector_remove_from_fbdev()
are called when registering / unregistering an mst connector and
dereference ifbdev.

v3: Drop additional null pointer checks in intel_fbdev_set_suspend(),
    intel_fbdev_output_poll_changed() and intel_fbdev_restore_mode()
    since they already check if ifbdev is not NULL, which is sufficient
    now that intel_fbdev_fini() is called on initialization failure.
    (Requested by Daniel Vetter <daniel.vetter@ffwll.ch>)
Signed-off-by: NLukas Wunner <lukas@wunner.de>
Link: http://patchwork.freedesktop.org/patch/msgid/d05f0edf121264a9d0adb8ca713fd8cc4ae068bf.1447938059.git.lukas@wunner.deSigned-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

The rotated view depends upon the rotation paramters, but thus far we
didn't bother checking for those. This seems to have been an issue
ever since this was introduce in

commit fe14d5f4
Author: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Date:   Wed Dec 10 17:27:58 2014 +0000

    drm/i915: Infrastructure for supporting different GGTT views per object

But userspace is allowed to reuse framebuffer backing storage with
different framebuffers with different pixel formats/stride/whatever.
And e.g. SNA indeed does this. Hence we must check for all the
paramters to match, not just that it's rotated.

v2: intel_plane_obj_offset also needs to construct the full view, to
avoid fallout since they don't fully match.

Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1444834266-12689-3-git-send-email-daniel.vetter@ffwll.chReviewed-by: NTvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

We don't need 2 separate unions.

Note that this was done intentinoally

Author: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Date:   Wed May 6 14:35:38 2015 +0300

    drm/i915: Add a partial GGTT view type

on Tvrtko's request, but without a clear justification. Rotated views
are also not checking for matching paramters in i915_ggtt_view_equal,
which seems like a bug. But this patch here doesn't change that.

Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1444834266-12689-2-git-send-email-daniel.vetter@ffwll.chReviewed-by: NTvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

It can't fail and there's even a WARN_ON suggesting that if it would,
it would be a disaster.

Correct this to make things less confusing.

Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1444834266-12689-1-git-send-email-daniel.vetter@ffwll.chReviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

    Found by static analysis tool.
Signed-off-by: NNamrta Salonie <namrta.salonie@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

This reverts

commit 6764e9f8
Author: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Date:   Thu Aug 27 15:44:06 2015 +0200

    drm/i915: skip modeset if compatible for everyone.

Bring back the i915.fastboot module parameter, disabled by default, due
to backlight regression on Chromebook Pixel 2015.

Apparently the firmware of the Chromebook in question enables the panel
but disables backlight to avoid a brief garbage scanout upon loading the
kernel/module. With fastboot, we leave the backlight untouched, in this
case disabled. The user would have to do a modeset (i.e. not just crank
up the brightness) to enable the backlight.

There is no clean fix readily available, so get back to the drawing
board by reverting.

[N.B. The reference below is for when the thread was included on public
lists, and some of the context had already been dropped by then.]
Reported-and-tested-by: NOlof Johansson <olof@lixom.net>
Acked-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
References: http://marc.info/?i=CAKMK7uES7xk05ki92oeX6gmvZWAh9f2vL7yz=6T+fGK9J3X7cQ@mail.gmail.com
Fixes: 6764e9f8 ("drm/i915: skip modeset if compatible for everyone.")
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1447921590-3785-1-git-send-email-jani.nikula@intel.com

MISSING_CASE() would have been useful to track down a recent problem in
intel_display_port_aux_power_domain(), so add it there and a few related
helpers. This was also suggested by Ville in his review of the latest
DMC/DC changes, we forgot to address that.
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NPatrik Jakobsson <patrik.jakobsson@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1447855045-7109-2-git-send-email-imre.deak@intel.com

Due to the current sharing of the DDI encoder between DP and HDMI
connectors we can run the DP detection after the HDMI detection has
already set the shared encoder's type. For now solve this keeping the
current behavior and running the detection in this case too. For a proper
solution Ville suggested to split the encoder into an HDMI and DP one, that
can be done as a follow-up.

This issue triggers the WARN in intel_display_port_aux_power_domain() and
was introduced in:
commit 25f78f58
Author: Ville Syrjälä <ville.syrjala@linux.intel.com>
Date:   Mon Nov 16 15:01:04 2015 +0100

    drm/i915: Clean up AUX power domain handling

CC: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
CC: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NPatrik Jakobsson <patrik.jakobsson@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1447855045-7109-1-git-send-email-imre.deak@intel.com

Their logic is exactly the same: check if the digital port is connected
and then call intel_dp_detect_dpcd(). So just put that logic in their
only caller: intel_dp_detect().
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/1447859970-9546-2-git-send-email-ander.conselvan.de.oliveira@intel.com

That call was moved to intel_dp_detect() in

commit d410b56d
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Tue Sep 2 20:03:59 2014 +0100

    drm/i915/dp: Refactor common eDP lid detection

but it seem to have been resurrected in the following commit, probably
due to a wrong merge conflict resolution.

commit 2a592bec
Author: Dave Airlie <airlied@redhat.com>
Date:   Mon Sep 1 16:58:12 2014 +1000

    drm/i915: handle G45/GM45 pulse detection connected state.
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/1447859970-9546-1-git-send-email-ander.conselvan.de.oliveira@intel.com

On the commit 3301d409 ("drm/i915: PSR: Fix DP_PSR_NO_TRAIN_ON_EXIT logic")'
we already had identified that DP_PSR_NO_TRAIN_ON_EXIT
doesn't mean we shouldn't send TPS patterns, however we start sending the
minimal TP1 as possible and no TP2.

For most of the panels this is ok, but we found a reported case where
this is not true and panel keeps frozen without updating the screen for a while.

We could just get this case after patch "PSR: Don't Skip aux handshake on
DP_PSR_NO_TRAIN_ON_EXIT." is applied since that one fix the
hard freeze on this kind of panels.

Reference: https://bugs.freedesktop.org/show_bug.cgi?id=91436#c19

Cc: Ivan Mitev <ivan.mitev@gmail.com>
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NDurgadoss R <durgadoss.r@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

Since the beginning there is a confusion on the meaning of this bit.

A previous patch had identified this already and fixed it partially:
'commit 3301d409 ("drm/i915: PSR: Fix DP_PSR_NO_TRAIN_ON_EXIT logic")

DP_PSR_NO_TRAIN_ON_EXIT means the source doesn't need to do the
training, but it doesn't tell to avoid TP patterns or to skip
aux handshake.

This patch fixes the hard freeze reported.

Reference: https://bugs.freedesktop.org/show_bug.cgi?id=91436
Reference: https://bugs.freedesktop.org/show_bug.cgi?id=91437

Cc: Ivan Mitev <ivan.mitev@gmail.com>
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NDurgadoss R <durgadoss.r@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

With 'commit 30886c5a ("drm/i915: VLV/CHV PSR: Increase wait delay
 time before active PSR.")' we fixed a blank screen when first
activation was happening immediately after PSR being enabled.
There we gave more time for idleness by increasing the delay
between re-activating sequences.

However, commit "drm/i915: Delay first PSR activation."
delay the first activation in a better way keeping a good PSR
residency. So, we can now reduce the delay on re-enable.
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NDurgadoss R <durgadoss.r@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

When debuging the frozen screen caused by HW tracking with low
power state I noticed that if we keep moving the mouse non stop
you will miss the screen updates for a while. At least
until we stop moving the mouse for a small time and move again.

The actual enabling should happen immediately after
Display Port enabling sequence finished with links trained and
everything enabled. However we face many issues when enabling PSR
right after a modeset.

On VLV/CHV we face blank screens on this scenario and on HSW+
we face a recoverable frozen screen, at least until next
exit-activate sequence.

Another workaround for the same issue here would be to increase
re-enable idle time from 100 to 500 as we did for VLV/CHV.
However this patch workaround this issue in a better
way since it doesn't reduce PSR residency and also
allow us to reduce the delay time between re-enables at least
on VLV/CHV.

This is also important to make the sysfs toggle working properly.
Signed-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: NDurgadoss R <durgadoss.r@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>