commit 09731280
Author: Imre Deak <imre.deak@intel.com>
Date:   Wed Feb 17 14:17:42 2016 +0200

    drm/i915: Add helper to get a display power ref if it was already enabled

left the rpm wakelock assertions unbalanced if CONFIG_PM was disabled as
intel_runtime_pm_get_if_in_use() would return true without incrementing
the local bookkeeping required for the assertions.

Fixes: 09731280 ("drm/i915: Add helper to get a display power ref if it was already enabled")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
CC: Mika Kuoppala <mika.kuoppala@intel.com>
CC: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
CC: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1456434628-22574-1-git-send-email-chris@chris-wilson.co.ukReviewed-by: NImre Deak <imre.deak@intel.com>
(cherry picked from commit 135dc79e)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

During system suspend we need to first disable power wells then
unitialize the display core. In case power well support is disabled we
did this in the wrong order, so fix this up.

Fixes: d314cd43 ("drm/i915: fix handling of the disable_power_well module option")
CC: stable@vger.kernel.org
CC: Patrik Jakobsson <patrik.jakobsson@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/1456778945-5411-1-git-send-email-imre.deak@intel.com
(cherry picked from commit 2622d79b)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

It has been observed that sometimes disabling the dc6 fails
and dc6 state pops back up, brief moment after disabling. This
has to be dmc save/restore timing issue or other bug in the
way dc states are handled.

Try to work around this issue as we don't have firmware fix
yet available. Verify that the value we wrote for the dmc sticks,
and also enforce it by rewriting it, if it didn't.

v2: Zero rereads on rewrite for extra paranoia (Imre)

Testcase: kms_flip/basic-flip-vs-dpms
References: https://bugs.freedesktop.org/show_bug.cgi?id=93768
Cc: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: NMika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455811089-27884-1-git-send-email-mika.kuoppala@intel.com
(cherry picked from commit 779cb5d3)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

The DMC can incorrectly run off and allow DC states on it's own. We
don't know the root-cause for this yet but this patch makes it more
visible.
Reviewed-by: NMika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: NPatrik Jakobsson <patrik.jakobsson@linux.intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455808874-22089-2-git-send-email-mika.kuoppala@intel.com
(cherry picked from commit 832dba88)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

We have many places in the code where we check if a given display power
domain is enabled and if so access registers backed by this power
domain. We assumed that some modeset lock will prevent the power
reference from vanishing in the middle of the HW access, but this
assumption doesn't always hold. In such cases we get either the wakeref
not held, or an unclaimed register access error message. To fix this in
a future-proof way that's independent of other locks wrap any such
access with a get_ref_if_enabled()/put_ref() pair.

Kudos to Ville and Joonas for the ideas of this new interface.

v2:
- init the power_domains ptr when declaring it everywhere (Joonas)
v3:
- don't report the device to be powered if runtime PM is disabled

CC: Mika Kuoppala <mika.kuoppala@intel.com>
CC: Chris Wilson <chris@chris-wilson.co.uk>
CC: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
CC: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1455711462-7442-1-git-send-email-imre.deak@intel.com
(cherry picked from commit 09731280)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>

pm_runtime_{use,dont_use}_autosuspend() controls whether the device's
sysfs power/autosuspend_delay_ms file is writeable or returns -EIO on
access to user space. Since

commit 25b181b4
Author: Imre Deak <imre.deak@intel.com>
Date:   Thu Dec 17 13:44:56 2015 +0200

  drm/i915: get a permanent RPM reference on platforms w/o RPM support

this sysfs file is writeable also on platforms without RPM support, but
userspace (at least IGT) depends on this file being unchangable to
determine whether the device supports runtime PM at all. So restore the
old behavior.

This gets rid of igt/pm_rpm failures on old platforms without RPM
support, where the test should be skipped.

Testcase: igt/pm_rpm/basic-rte
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NDavid Weinehall <david.weinehall@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450371873-878-1-git-send-email-imre.deak@intel.com

In some cases we want to check whether we hold an RPM wakelock reference
for the whole duration of a sequence. To achieve this add a new RPM
atomic sequence counter that we increment any time the wakelock refcount
drops to zero.  Check whether the sequence number stays the same during
the atomic section and that we hold the wakelock at the beginning of the
section.

Motivated by Chris.

v2-v3:
- unchanged
v4:
- swap the order of atomic_read() and assert_rpm_wakelock_held() in
  assert_rpm_atomic_begin() to avoid race
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> (v3)
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450203038-5150-10-git-send-email-imre.deak@intel.com

With this change we have the corresponding wake lock checks in both the
rpm get and put functions.

v2-v3:
- unchanged
v4:
- keep the corresponding check in the get helper (Chris)
v5:
- add a note to the commit message that with this change we have the
  checks both in the rpm get and put functions (Joonas)
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450203038-5150-9-git-send-email-imre.deak@intel.com

Atm, we assert that the device is not suspended until the point when the
device is truly put to a suspended state. This is fine, but we can catch
more problems if we check that RPM refcount is non-zero. After that one
drops to zero we shouldn't access the device any more, even if the actual
device suspend may be delayed. Change assert_rpm_wakelock_held()
accordingly to check for a non-zero RPM refcount in addition to the
current device-not-suspended check.

For the new asserts to work we need to annotate every place explicitly in
the code where we expect that the device is powered. The places where we
only assume this, but may not hold an RPM reference:
- driver load
  We assume the device to be powered until we enable RPM. Make this
  explicit by taking an RPM reference around the load function.
- system and runtime sudpend/resume handlers
  These handlers are called when the RPM reference becomes 0 and know the
  exact point after which the device can get powered off. Disable the
  RPM-reference-held check for their duration.
- the IRQ, hangcheck and RPS work handlers
  These handlers are flushed in the system/runtime suspend handler
  before the device is powered off, so it's guaranteed that they won't
  run while the device is powered off even though they don't hold any
  RPM reference. Disable the RPM-reference-held check for their duration.

In all these cases we still check that the device is not suspended.
These explicit annotations also have the positive side effect of
documenting our assumptions better.

This caught additional WARNs from the atomic modeset path, those should
be fixed separately.

v2:
- remove the redundant HAS_RUNTIME_PM check (moved to patch 1) (Ville)
v3:
- use a new dedicated RPM wakelock refcount to also catch cases where
  our own RPM get/put functions were not called (Chris)
- assert also that the new RPM wakelock refcount is 0 in the RPM
  suspend handler (Chris)
- change the assert error message to be more meaningful (Chris)
- prevent false assert errors and check that the RPM wakelock is 0 in
  the RPM resume handler too
- prevent false assert errors in the hangcheck work too
- add a device not suspended assert check to the hangcheck work
v4:
- rename disable/enable_rpm_asserts to disable/enable_rpm_wakeref_asserts
  and wakelock_count to wakeref_count
- disable the wakeref asserts in the IRQ handlers and RPS work too
- update/clarify commit message
v5:
- mark places we plan to change to use proper RPM refcounting with
  separate DISABLE/ENABLE_RPM_WAKEREF_ASSERTS aliases (Chris)
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1450227139-13471-1-git-send-email-imre.deak@intel.com

Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NChris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1450203038-5150-7-git-send-email-imre.deak@intel.com

We don't really need to check this flag in the get/put/assert helpers,
as on platforms without RPM support we won't ever enable RPM. That means
pm.suspend will be always false and the assert will be always true.

Do this to simplify the code and to let us extend the RPM asserts to all
platforms for a better coverage.

Motivated by Ville.

v2-v3:
- unchanged
v4:
- remove the HAS_RUNTIME_PM check from intel_runtime_pm_enable() too
  made possible by the previous two patches
v5:
- rebased on the previous new patch in the series that keeps
  HAS_RUNTIME_PM() in intel_runtime_pm_enable() with a permanent
  reference taken there
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> (v3)
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450352931-16498-1-git-send-email-imre.deak@intel.com

Currently we disable RPM functionality on platforms that doesn't support
this by not putting/getting the RPM reference we receive from the RPM
core during driver loading/unloading respectively. This is somewhat
obscure, so make it more explicit by keeping a reference dedicated for
this particular purpose whenever the driver is loaded. This makes it
possible to remove the HAS_RUNTIME_PM() special casing from every other
places in the next patch.

v2:
- fix intel_runtime_pm_get vs. intel_runtime_pm_put in
  intel_power_domains_fini()
v3:
- take only a low level RPM reference so the ref tracking asserts
  continue to work (Ville)
- update the commit message
- move the patch earlier for bisectability
Suggested-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
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/1450352696-16135-1-git-send-email-imre.deak@intel.com

We can make the RPM dependency on RC6 explcit in the code by taking an
actual RPM reference, instead of avoiding to drop the initial one. This
will also enable us to remove the HAS_RUNTIME_PM special casing from
more places in the next patch.

v2:
- fixed typo in commit message (Joonas)
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450203038-5150-4-git-send-email-imre.deak@intel.com

Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450203038-5150-2-git-send-email-imre.deak@intel.com

Currently the gmbus code uses intel_aux_display_runtime_get/put in an
effort to make sure the hardware is powered up sufficiently for gmbus.
That function only takes the runtime PM reference which on VLV/CHV/BXT
is not enough. We need the disp2d/pipe-a well on VLV/CHV and power well
2 on BXT. So add a new power domnain for gmbus and kill off the now
unused intel_aux_display_runtime_get/put. And change
intel_hdmi_set_edid() to use the gmbus power domain too since that's all
we need there.

Also toss in a BUILD_BUG_ON() to catch problems if we run out of
bits for power domains. We're already really close to the limit...

[Patrik: Add gmbus string to debugfs output]
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NPatrik Jakobsson <patrik.jakobsson@linux.intel.com>
[Cherry-picked from drm-intel-next-queued f0ab43e6 (Imre)]
Signed-off-by: NImre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448643329-18675-3-git-send-email-imre.deak@intel.comSigned-off-by: NJani Nikula <jani.nikula@intel.com>

BXT power well support is not yet stable.  Starting with patch

        commit 9f836f90
        Author: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
        Date:   Mon Nov 16 16:20:01 2015 +0100

            drm/i915/gen9: Turn DC handling into a power well

DPMS off operations may actually cause the entire system to powerdown or
reboot.  Disable power well support for now until Broxton gets fixes
similar to what we have for SKL.

Cc: Imre Deak <imre.deak@intel.com>
Cc: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
References: http://lists.freedesktop.org/archives/intel-gfx/2015-November/081037.htmlSigned-off-by: NMatt Roper <matthew.d.roper@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448990818-11005-1-git-send-email-matthew.d.roper@intel.comReviewed-by: NImre Deak <imre.deak@intel.com>

We have serious dangling else bugs waiting to happen in our for_each_
style macros with ifs. Consider, for example,

 #define for_each_power_domain(domain, mask)                         \
         for ((domain) = 0; (domain) < POWER_DOMAIN_NUM; (domain)++) \
                 if ((1 << (domain)) & (mask))

If this is used in context:

	if (condition)
		for_each_power_domain(domain, mask);
	else
		foo();

foo() will be called for each domain *not* in mask, if condition holds,
and not at all if condition doesn't hold.

Fix this by reversing the conditions in the macros, and adding an else
branch for the "for each" block, so that other if/else blocks can't
interfere. Provide a "for_each_if" helper macro to make it easier to get
this right.

v2: move for_each_if to drmP.h in a separate patch.
Reviewed-by: NDaniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448392916-2281-2-git-send-email-jani.nikula@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

v2: Use _unsafe (Jani)
v3: Allow specifying specific DC-states instead of just DC6 (Imre)
Signed-off-by: NPatrik Jakobsson <patrik.jakobsson@linux.intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1447682467-6237-3-git-send-email-patrik.jakobsson@linux.intel.com

Handle DC off as a power well where enabling the power well will prevent
the DMC to enter selected DC states (required around modesets and Aux
A). Disabling the power well will allow DC states again. For now the
highest DC state is DC6 for Skylake and DC5 for Broxton but will be
configurable for Skylake in a later patch.

v2: Check both DC5 and DC6 bits in power well enabled function (Ville)
v3:
- Remove unneeded DC_OFF case in skl_set_power_well() (Imre)
- Add PW2 dependency to DC_OFF (Imre)
v4: Put DC_OFF before PW2 in BXT power well array
Signed-off-by: NPatrik Jakobsson <patrik.jakobsson@linux.intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
[fixed line over 80 and parenthesis alignment checkpatch warns (imre)]
Link: http://patchwork.freedesktop.org/patch/msgid/1447687201-24759-1-git-send-email-patrik.jakobsson@linux.intel.com

PG2 enabled is not a requirement for disabling DC5. It's just one
of the reasons why the DMC wouldn't enter DC5. During modeset we don't
care about PG2 from a DC perspective, only the fact that DC5/DC6 is not
allowed.
Signed-off-by: NPatrik Jakobsson <patrik.jakobsson@linux.intel.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/1447084107-8521-9-git-send-email-patrik.jakobsson@linux.intel.com

We never make use of the distinction between 2 vs 4 lanes so combine
them into a per port domain instead. This saves us a few bits in the
power domain mask. Change suggested by Ville.
Signed-off-by: NPatrik Jakobsson <patrik.jakobsson@linux.intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1447084107-8521-7-git-send-email-patrik.jakobsson@linux.intel.com

All the DDI power domains are already excluded from
SKL_DISPLAY_ALWAYS_ON_POWER_DOMAINS on account of
excluding SKL_DISPLAY_POWERWELL_1_POWER_DOMAINS and
SKL_DISPLAY_POWERWELL_2_POWER_DOMAINS, no need to spell them out again.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NPatrik Jakobsson <patrik.jakobsson@linux.intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1447084107-8521-6-git-send-email-patrik.jakobsson@linux.intel.com

Currently the gmbus code uses intel_aux_display_runtime_get/put in an
effort to make sure the hardware is powered up sufficiently for gmbus.
That function only takes the runtime PM reference which on VLV/CHV/BXT
is not enough. We need the disp2d/pipe-a well on VLV/CHV and power well
2 on BXT. So add a new power domnain for gmbus and kill off the now
unused intel_aux_display_runtime_get/put. And change
intel_hdmi_set_edid() to use the gmbus power domain too since that's all
we need there.

Also toss in a BUILD_BUG_ON() to catch problems if we run out of
bits for power domains. We're already really close to the limit...

[Patrik: Add gmbus string to debugfs output]
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: NPatrik Jakobsson <patrik.jakobsson@linux.intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1447084107-8521-5-git-send-email-patrik.jakobsson@linux.intel.com

Move call to gen9_set_dc_state_debugmask_memory_up() into
gen9_set_dc_state() to prevent us missing it somewhere.
Signed-off-by: NPatrik Jakobsson <patrik.jakobsson@linux.intel.com>
Reviewed-by: NImre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1447084107-8521-3-git-send-email-patrik.jakobsson@linux.intel.com

When this option is 0 (so the power well support is disabled) we are
supposed to enable all power wells once and don't disable them unless we
system suspend the device. Currently if the option is 0, we can call the
power well enable handlers multiple times, whenever their refcount
changes from 0->1. This may not be a problem for the HW, but it's not
logical and may trigger some warnings in the power well code which
doesn't expect this. So simply keep around a reference while we are
not system suspended to solve this. For simplicity mark the module
option read only, so we don't need to deal with re-enabling the feature
during runtime. If someone really needs that it could be added later in
a more proper way.

v2:
- fix typo in comment in intel_power_domains_suspend() (Patrik)
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/1447775063-24438-1-git-send-email-imre.deak@intel.com

We don't need to reinit DDI and IRQs during PW1 enabling any more, since
we don't toggle PW1 on-demand any more. We enable PW1 only as part of
the display core init sequence and after this we initialize both DDI and
IRQs later in the init sequence. So remove these init steps from the
power well code.
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/1446657859-9598-11-git-send-email-imre.deak@intel.com

We need to disable the DC states during display core init to sanitize
the HW state we inherit from the BIOS. We need to disable it during
display core uninit too, since the power well framework will leave it
enabled (since we get to the display core uninit step with all power
domains disabled already).
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/1446657859-9598-9-git-send-email-imre.deak@intel.com

Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NPatrik Jakobsson <patrik.jakobsson@linux.intel.com>
[fix line over 80 chars checkpatch WARN in gen9_set_dc_state() (imre)]
Link: http://patchwork.freedesktop.org/patch/msgid/1446657859-9598-8-git-send-email-imre.deak@intel.com

With the DMC firmware installed we don't need to handle HW resources
that are handled automatically by the firmware. Besides being redundant
this can also interfere with the firmware, possibly getting it into a
broken/blocked state. The on-demand handling of PW1 was already half-way
removed, MISC IO was still handled in this way. After the last patch we
init/uninit these HW resources manually as part of the display core
init/uninit sequence, so we can now remove the on-demand handling for
these completely.

We still keep around the power wells (with no domains attached to them)
since the manual toggling during display core init/uninit happens via
the current API.
Signed-off-by: NImre Deak <imre.deak@intel.com>
Reviewed-by: NPatrik Jakobsson <patrik.jakobsson@linux.intel.com>
[s/beeing/being/ in commit message (imre)]
Link: http://patchwork.freedesktop.org/patch/msgid/1446657859-9598-7-git-send-email-imre.deak@intel.com

We need to initialize the display core part early, before initializing
the rest of the display power state. This is also described in the bspec
termed "Display initialization sequence". Atm we run this sequence
during driver loading after power domain HW state initialization which
is too late and during runtime suspend/resume which is unneeded and can
interere with DMC functionality which handles HW resources toggled
by this init/uninit sequence automatically. The init sequence must be
run as the first step of HW power state initialization and during
system resume. The uninit sequence must be run during system suspend.

To address the above move the init sequence to the initial HW power
state setup and the uninit sequence to a new power domains suspend
function called during system suspend.

As part of the init sequence we also have to reprogram the DMC firmware
as it's lost across a system suspend/resume cycle.

After this change CD clock initialization during driver loading will
happen only later after other dependent HW/SW parts are initialized,
while during system resume it will get initialized as the last step of
the init sequence. This distinction can be removed by some refactoring
of platform independent parts. I left this refactoring out from this
series since I didn't want to change non-SKL parts. This is a TODO for
later.

v2:
- fix error path in i915_drm_suspend_late()
- don't try to re-program the DMC firmware if it failed to load
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/1447774433-20834-1-git-send-email-imre.deak@intel.com

Give a more proper name to this function.
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/1446657859-9598-5-git-send-email-imre.deak@intel.com

Before this patch, we used the intel_display_power_{get,put} functions
to make sure the PW1 and Misc I/O power wells were enabled all the
time while LCPLL was enabled. We called a get() at
intel_ddi_pll_init() when we discovered that LCPLL was enabled, then
we would call put/get at skl_{un,}init_cdclk().

The problem is that skl_uninit_cdclk() is indirectly called by
intel_runtime_suspend(). So it will only release its power well
_after_ we already decided to runtime suspend. But since we only
decide to runtime suspend after all power wells and refcounts are
released, that basically means we will never decide to runtime
suspend.

So what this patch does to fix that problem is move the PW1 + Misc I/O
power well handling out of the runtime PM mechanism: instead of
calling intel_display_power_{get_put} - functions that touch the
refcount -, we'll call the low level intel_power_well_{en,dis}able,
which don't change the refcount. This way, it is now possible for the
refcount to actually reach zero, and we'll now start runtime
suspending/resuming.

v2 (from Paulo):
  - Write a commit message since the original patch left it empty.
  - Rebase after the intel_power_well_{en,dis}able rename.
  - Use lookup_power_well() instead of hardcoded indexes.

Testcase: igt/pm_rpm/rte (and every other rpm test)
Signed-off-by: NDamien Lespiau <damien.lespiau@intel.com>
Reviewed-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: NPaulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: NPatrik Jakobsson <patrik.jakobsson@linux.intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92211
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92605Signed-off-by: NImre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446657859-9598-4-git-send-email-imre.deak@intel.com

The current lookup code wouldn't find a power well if it's not in any
power domain. There wasn't any power wells before but an upcoming patch
will detach the power domains from power well#1 and the MISC IO power
wells, so fix things up accordingly.
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/1446657859-9598-3-git-send-email-imre.deak@intel.com

lookup_power_well() expects uniq power well IDs, but atm we have
uninitialized IDs which would clash with those power wells with a 0
ID. This wasn't a problem so far since nothing looked up such a power
well, but an upcoming patch will (Misc IO for SKL), so fix this up on
platforms where this matters.
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/1446657859-9598-2-git-send-email-imre.deak@intel.com

As during disabling dc6 no need to check for csr firmware
loading status, so removed the assert call (Requested by Damien).

Cc: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: NAnimesh Manna <animesh.manna@intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Tested-by: Daniel Stone <daniels@collabora.com> # SKL
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446069547-24760-14-git-send-email-imre.deak@intel.com

This removes two anti-patterns:
- Locking shouldn't be used to synchronize with async work (of any
  form, whether callbacks, workers or other threads). This is what the
  mutex_lock/unlock seems to have been for in intel_csr_load_program.
  Instead ordering should be ensured with the generic
  wait_for_completion()/complete(). Or more specific functions
  provided by the core kernel like e.g.
  flush_work()/cancel_work_sync() in the case of synchronizing with a
  work item.

- Don't invent own completion like the following code did with the
  (already removed) wait_for(csr_load_status_get()) pattern - it's
  really hard to get these right when you want them to be _really_
  correct (and be fast) in all cases. Furthermore it's easier to read
  code using the well-known primitives than new ones using
  non-standard names.

Before enabling/disabling DC6 check if the firmware is loaded
successfully. This is guaranteed during runtime s/r, since otherwise we
don't enable RPM, but not during system s/r.

Note that it's still unclear whether we need to enable/disable DC6
during system s/r, until that's clarified, keep the current behavior and
enable/disable DC6.

Also after this patch there is a race during system s/r where the
firmware may not be loaded yet, that's addressed in an upcoming patch.

v2-v3:
- unchanged
v4:
- rebased on latest drm-intel-nightly

Cc: Damien Lespiau <damien.lespiau@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Sunil Kamath <sunil.kamath@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Signed-off-by: NAnimesh Manna <animesh.manna@intel.com>
[imre: added code and note about checking if the firmware loaded ok,
 before enabling/disabling it]
Reviewed-by: NAnimesh Manna <animesh.manna@intel.com>
Signed-off-by: NImre Deak <imre.deak@intel.com>
Tested-by: Daniel Stone <daniels@collabora.com> # SKL
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1447341037-2623-1-git-send-email-imre.deak@intel.com

Avoids non-static functions since all the callers are in intel_rpm.c.

Cc: Damien Lespiau <damien.lespiau@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Sunil Kamath <sunil.kamath@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@intel.com>
Signed-off-by: NAnimesh Manna <animesh.manna@intel.com>
[imre: removed note about reg definitions from commit message, since
 it's not relevant any more]
Signed-off-by: NImre Deak <imre.deak@intel.com>
Tested-by: Daniel Stone <daniels@collabora.com> # SKL
[Jani: make assert_csr_loaded static]
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1446069547-24760-4-git-send-email-imre.deak@intel.com