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200 commits

Author SHA1 Message Date
Dave Airlie
1f31c69dac Merge branch 'drm-intel-fixes' of git://people.freedesktop.org/~danvet/drm-intel into drm-next
Daniel writes:

Bigger -fixes pile, mostly because I've included Ajax' DP dongle stuff,
as discussed on irc. Otherwise just small things:
- regression fix to finally make 6bpc auto-dither on dp work (Jani)
- reinstate an snb ctx w/a that accidentally got lost in a rework (Chris)
- fixup the DP train sequence, logic-goof-up uncovered by Coverty (Chris)
- fix set_caching locking (Ben)
- fix spurious segfault on con-current gtt mmap faulting (Dimitry and Mika)
- some pageflip correctness fixes (still hunting down some issues, but
  these are the worst offenders of confused code that we've tracked down
  thus far) from Chris and me
- fixup swizzling settings on vlv (Jesse)
- gt_mode w/a from Ben added, fixes snb gt1 rc6+hw ctx hangs.

* 'drm-intel-fixes' of git://people.freedesktop.org/~danvet/drm-intel:
  drm/i915: Fix GT_MODE default value
  drm/i915: don't frob the vblank ts in finish_page_flip
  drm/i915: call drm_handle_vblank before finish_page_flip
  drm/i915: print warning if vmi915_gem_fault error is not handled
  drm/i915: EBUSY status handling added to i915_gem_fault().
  drm/i915: Try harder to complete DP training pattern 1
  drm/i915: set swizzling to none on VLV
  drm/dp: Make sink count DP 1.2 aware
  drm/dp: Document DP spec versions for various DPCD registers
  drm/i915/dp: Be smarter about connection sense for branch devices
  drm/i915/dp: Fetch downstream port info if needed during DPCD fetch
  drm/dp: Update DPCD defines
  drm: Export drm_probe_ddc()
  drm/i915: Flush the pending flips on the CRTC before modification
  drm/i915: Actually invalidate the TLB for the SandyBridge HW contexts w/a
  drm/i915: Fix set_caching locking
  drm/i915: use adjusted_mode instead of mode for checking the 6bpc force flag
2012-10-07 21:13:54 +10:00
Linus Torvalds
612a9aab56 Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux
Pull drm merge (part 1) from Dave Airlie:
 "So first of all my tree and uapi stuff has a conflict mess, its my
  fault as the nouveau stuff didn't hit -next as were trying to rebase
  regressions out of it before we merged.

  Highlights:
   - SH mobile modesetting driver and associated helpers
   - some DRM core documentation
   - i915 modesetting rework, haswell hdmi, haswell and vlv fixes, write
     combined pte writing, ilk rc6 support,
   - nouveau: major driver rework into a hw core driver, makes features
     like SLI a lot saner to implement,
   - psb: add eDP/DP support for Cedarview
   - radeon: 2 layer page tables, async VM pte updates, better PLL
     selection for > 2 screens, better ACPI interactions

  The rest is general grab bag of fixes.

  So why part 1? well I have the exynos pull req which came in a bit
  late but was waiting for me to do something they shouldn't have and it
  looks fairly safe, and David Howells has some more header cleanups
  he'd like me to pull, that seem like a good idea, but I'd like to get
  this merge out of the way so -next dosen't get blocked."

Tons of conflicts mostly due to silly include line changes, but mostly
mindless.  A few other small semantic conflicts too, noted from Dave's
pre-merged branch.

* 'drm-next' of git://people.freedesktop.org/~airlied/linux: (447 commits)
  drm/nv98/crypt: fix fuc build with latest envyas
  drm/nouveau/devinit: fixup various issues with subdev ctor/init ordering
  drm/nv41/vm: fix and enable use of "real" pciegart
  drm/nv44/vm: fix and enable use of "real" pciegart
  drm/nv04/dmaobj: fixup vm target handling in preparation for nv4x pcie
  drm/nouveau: store supported dma mask in vmmgr
  drm/nvc0/ibus: initial implementation of subdev
  drm/nouveau/therm: add support for fan-control modes
  drm/nouveau/hwmon: rename pwm0* to pmw1* to follow hwmon's rules
  drm/nouveau/therm: calculate the pwm divisor on nv50+
  drm/nouveau/fan: rewrite the fan tachometer driver to get more precision, faster
  drm/nouveau/therm: move thermal-related functions to the therm subdev
  drm/nouveau/bios: parse the pwm divisor from the perf table
  drm/nouveau/therm: use the EXTDEV table to detect i2c monitoring devices
  drm/nouveau/therm: rework thermal table parsing
  drm/nouveau/gpio: expose the PWM/TOGGLE parameter found in the gpio vbios table
  drm/nouveau: fix pm initialization order
  drm/nouveau/bios: check that fixed tvdac gpio data is valid before using it
  drm/nouveau: log channel debug/error messages from client object rather than drm client
  drm/nouveau: have drm debugging macros build on top of core macros
  ...
2012-10-03 23:29:23 -07:00
David Howells
760285e7e7 UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/
Convert #include "..." to #include <path/...> in drivers/gpu/.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Dave Airlie <airlied@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>
2012-10-02 18:01:07 +01:00
Adam Jackson
edb39244fa drm/i915/dp: Fetch downstream port info if needed during DPCD fetch
v2: Fix parenthesis mismatch, spotted by Jani Nikula

Tested-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Adam Jackson <ajax@redhat.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
[danvet: Fixup merge conflict and MAX_DOWNSTREAM #define as spotted by
Jani.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-10-02 18:06:06 +02:00
Daniel Vetter
bf49ec8c52 drm/i915: add encoder->pre_enable/post_disable
The cpu eDP encoder has some horrible hacks to set up the DP pll at
the right time. To be able to move them to the right place, add some
more encoder callbacks so that this can happen at the right time.

LVDS has some similar funky hacks, but that would require more work
(we need to move around the pll setup a bit). Hence for now only
wire these new callbacks up for ilk+ - we only have cpu eDP on these
platforms.

v2: Bikeshed the vtable ordering, requested by Chris Wilson.

Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-20 14:23:02 +02:00
Daniel Vetter
a1ceb67751 Merge the modeset-rework, basic conversion into drm-intel-next
As a quick reference I'll detail the motivation and design of the new code a
bit here (mostly stitched together from patchbomb announcements and commits
introducing the new concepts).

The crtc helper code has the fundamental assumption that encoders and crtcs can
be enabled/disabled in any order, as long as we take care of depencies (which
means that enabled encoders need an enabled crtc to feed them data,
essentially).

Our hw works differently. We already have tons of ugly cases where crtc code
enables encoder hw (or encoder->mode_set enables stuff that should only be
enabled in enocder->commit) to work around these issues. But on the disable
side we can't pull off similar tricks - there we actually need to rework the
modeset sequence that controls all this. And this is also the real motivation
why I've finally undertaken this rewrite: eDP on my shiny new Ivybridge
Ultrabook is broken, and it's broken due to the wrong disable sequence ...

The new code introduces a few interfaces and concepts:

- Add new encoder->enable/disable functions which are directly called from the
crtc->enable/disable function. This ensures that the encoder's can be
enabled/disabled at a very specific in the modeset sequence, controlled by our
platform specific code (instead of the crtc helper code calling them at a time
it deems convenient).

- Rework the dpms code - our code has mostly 1:1 connector:encoder mappings and
does support cloning on only a few encoders, so we can simplify things quite a
bit.

- Also only ever disable/enable the entire output pipeline. This ensures that
we obey the right sequence of enabling/disabling things, trying to be clever
here mostly just complicates the code and results in bugs. For cloneable
encoders this requires a bit of special handling to ensure that outputs can
still be disabled individually, but it simplifies the common case.

- Add infrastructure to read out the current hw state. No amount of careful
ordering will help us if we brick the hw on the initial modeset setup. Which
could happen if we just randomly disable things, oblivious to the state set up
by the bios. Hence we need to be able to read that out. As a benefit, we grow a
few generic functions useful to cross-check our modeset code with actual hw
state.

With all this in place, we can copy&paste the crtc helper code into the
drm/i915 driver and start to rework it:

- As detailed above, the new code only disables/enables an entire output pipe.
As a preparation for global mode-changes (e.g. reassigning shared resources) it
keeps track of which pipes need to be touched by a set of bitmasks.

- To ensure that we correctly disable the current display pipes, we need to
know the currently active connector/encoder/crtc linking. The old crtc helper
simply overwrote these links with the new setup, the new code stages the new
links in ->new_* pointers. Those get commited to the real linking pointers once
the old output configuration has been torn down, before the ->mode_set
callbacks are called.

- Finally the code adds tons of self-consistency checks by employing the new hw
state readout functions to cross-check the actual hw state with what the
datastructure think it should be. These checks are done both after every
modeset and after the hw state has been read out and sanitized at boot/resume
time. All these checks greatly helped in tracking down regressions and bugs in
the new code.

With this new basis, a lot of cleanups and improvements to the code are now
possible (besides the DP fixes that ultimately made me write this), but not yet
done:

- I think we should create struct intel_mode and use it as the adjusted mode
everywhere to store little pieces like needs_tvclock, pipe dithering values or
dp link parameters. That would still be a layering violation, but at least we
wouldn't need to recompute these kinds of things in intel_display.c. Especially
the port bpc computation needed for selecting the pipe bpc and dithering
settings in intel_display.c is rather gross.

- In a related rework we could implement ->mode_valid in terms of ->mode_fixup
in a generic way - I've hunted down too many bugs where ->mode_valid did the
right thing, but ->mode_fixup didn't. Or vice versa, resulting in funny bugs
for user-supplied modes.

- Ditch the idea to rework the hdp handling in the common crtc helper code and
just move things to i915.ko. Which would rid us of the ->detect crtc helper
dependencies.

- LVDS wire pair and pll enabling is all done in the crtc->mode_set function
currently. We should be able to move this to the crtc_enable callbacks (or in
the case of the LVDS wire pair enabling, into some encoder callback).

Last, but not least, this new code should also help in enabling a few neat
features: The hw state readout code prepares (but there are still big pieces
missing) for fastboot, i.e. avoiding the inital modeset at boot-up and just
taking over the configuration left behind by the bios. We also should be able
to extend the configuration checks in the beginning of the modeset sequence and
make better decisions about shared resources (which is the entire point behind
the atomic/global modeset ioctl).

Tested-by: Jani Nikula <jani.nikula@intel.com>
Tested-by: Ben Widawsky <ben@bwidawsk.net>
Tested-by: Damien Lespiau <damien.lespiau@intel.com>
Tested-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: Vijay Purushothaman <vijay.a.purushothaman@intel.com>
Acked-by: Vijay Purushothaman <vijay.a.purushothaman@intel.com>
Tested-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Acked-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Tested-by: Jesse Barnes <jbarnes@virtuousgeek.org>

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-06 22:52:43 +02:00
Daniel Vetter
b980514c9a drm/i915: improve modeset state checking after dpms calls
Now that we have solid modeset state tracking and checking code in
place, we can do the Full Monty also after dpms calls.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-06 08:21:31 +02:00
Daniel Vetter
a261b246eb drm/i915: disable all crtcs at suspend time
We need this to avoid confusing the hw state readout code with the cpt
pch plls at resume time: We'd read the new pipe state (which is
disabled), but still believe that we have a life pll connected to that
pipe (from before the suspend). Hence properly disable pipes to clear
out all the residual state.

This has the neat side-effect that we don't enable ports prematurely
by restoring bogus state from the saved register values.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-06 08:21:29 +02:00
Daniel Vetter
ea9d758d6d drm/i915: push commit_output_state past the crtc/encoder preparing
With this change we can (finally!) rip out a few of the temporary hacks
and clean up a few other things:
- Kill intel_crtc_prepare_encoders, now unused.
- Kill the hacks in the crtc_disable/enable functions to always call the
  encoder callbacks, we now always call the crtc functions with the right
  encoder -> crtc links.
- Also push down the crtc->enable, encoder and connector dpms state
  updates. Unfortunately we can't add a WARN in the crtc_disable
  callbacks to ensure that the crtc is always still enabled when
  disabling an output pipe - the crtc sanitizer of the hw readout path
  can hit this when it needs to disable an active pipe without any
  enabled outputs.
- Only call crtc->disable if the pipe is already enabled - again avoids
  running afoul of the new WARN.

v2: Copy&paste our own version of crtc_in_use, too.

v3: We need to update the dpms an encoder->connectors_active states,
too.

v4: I've forgotten to kill the unconditional encoder->disable calls in
the crtc_disable functions.

v5: Rip out leftover debug printk.

v6: Properly clear intel_encoder->connectors_active. This wasn't
properly cleared when disabling an encoder because it was no longer on
the new connector list, but the crtc was still enabled (i.e. switching
the encoder of an active crtc). Reported by Jani Nikula.

v7: Don't clobber the encoder->connectors_active state of untouched
encoders. Since X likes to first disable all outputs with dpms off
before setting a new framebuffer, this hit a few warnings. Reported by
Paulo Zanoni.

v8: Kill the now stale comment warning that intel_crtc->active is not
always updated at the right times.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-06 08:21:29 +02:00
Daniel Vetter
1f70385510 drm/i915: s/intel_encoder_disable/intel_encoder_noop
Because that's what it is. Unfortunately we can't rip this out because
the fb helper has an incetious relationship with the crtc helper - it
likes to call disable_unused_functions, among other things.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-06 08:21:27 +02:00
Daniel Vetter
6ed0f796c2 drm/i915: use staged outuput config in tv->mode_fixup
The "is this encoder cloned" check will be reused by the lvds encoder,
hence exract it.

v2: Be a bit more careful about that we need to check the new, staged
ouput configuration in the check_non_cloned helper ...

v3: Kill the double negation with s/!non_cloned/is_cloned/, suggested
by Jesse Barnes.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-06 08:20:31 +02:00
Daniel Vetter
94352cf9a5 drm/i915: push crtc->fb update into pipe_set_base
Passing in the old fb, having overwritten the current fb, leads to
some neatly convoluted code. It's much simpler if we defer the
crtc->fb update to the place that updates the hw, in pipe_set_base.
This way we also don't need to restore anything in case something
fails - we only update crtc->fb once things have succeeded.

The real reason for this change is that now we keep the old fb
assigned to crtc->fb, which allows us to finally move the crtc disable
case into the common low-level set_mode function in the next patch.

Also don't clobber crtc->x and crtc->y, we neatly pass these down the
callchain already. Unfortunately we can't do the same with crtc->mode,
because that one is being used in the mode_set callbacks.

v2: Don't restore the drm_crtc object any more on failed modesets,
since we've lose an fb reference otherwise. Also (and this is the
reason this has been found), this totally confused the modeset state
tracking, since it clobbers crtc->enabled. Issue reported by Paulo
Zanoni.

v3: Rip out the entire crtc saving into struct intel_set_config, not
just the restoring part.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-06 08:03:10 +02:00
Daniel Vetter
9a93585699 drm/i915: stage modeset output changes
This is the core of the new modeset logic.

The current code which is based upon the crtc helper code first
updates all the link of the new display pipeline and then calls the
lower-level set_mode function to execute the required callbacks to get
there. The issue with this approach is that for disabling we need to
know the _current_ display pipe state, not the new one.

Hence we need to stage the new state of the display pipe and only
update it once we have disabled the current configuration and before we
start to update the hw registers with the new configuration.

This patch here just prepares the ground by switching the new output
state computation to these staging pointers. To make it clearer,
rename the old update_output_state function to stage_output_state.

A few peculiarities:
- We're also calling the set_mode function at various places to update
  properties. Hence after a successfule modeset we need to stage the
  current configuration (for otherwise we might fall back again). This
  happens automatically because as part of the (successful) modeset we
  need to copy the staged state to the real one. But for the hw
  readout code we need to make sure that this happens, too.
- Teach the new staged output state computation code the required
  smarts to handle the disabling of outputs. The current code handles
  this in a special case, but to better handle global modeset changes
  covering more than one crtc, we want to do this all in the same
  low-level modeset code.
- The actual modeset code is still a bit ugly and wants to know the new
  crtc->enabled state a bit early. Follow-on patches will clean that
  up, for now we have to apply the staged output configuration early,
  outside of the set_mode functions.
- Improve/add comments in stage_output_state.

Essentially all that is left to do now is move the disabling code into
set_mode and then move the staged state update code also into
set_mode, at the right place between disabling things and calling the
mode_set callbacks for the new configuration.

v2: Disabling a crtc works by passing in a NULL mode or fb, userspace
doesn't hand in the list of connectors. We therefore need to detect
this case manually and tear down all the output links.

v3: Properly update the output staging pointers after having read out
the hw state.

v4: Simplify the code, add more DRM_DEBUG_KMS output and check a few
assumptions with WARN_ON. Essentially all things that I've noticed
while debugging issues in other places of the code.

v4: Correctly disable the old set of connectors when enabling an
already enabled crtc on a new set of crtc. Reported by Paulo Zanoni.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-06 08:02:57 +02:00
Daniel Vetter
1aa4b628ee drm/i915: don't save all the encoder/crtc state in set_config
We actually only touch the connector -> encoder and encoder -> crtc
linking. So it's enough to just save/restore that.

While at it, also switch to kcalloc to allocate these arrays (omission
in the commit message spotted by Jesse Barnes).

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-06 08:02:40 +02:00
Daniel Vetter
5e2b584ed1 drm/i915: extract intel_set_config_compute_mode_changes
This computes what exactly changed in the modeset configuration, i.e.
whether a full modeset is required or only an update of the
framebuffer base address or no change at all.

In the future we might add more checks for e.g. when only the output
mode changed, so that we could do a minimal modeset for outputs that
support this. Like the lvds/eDP panels where we only need to update
the panel fitter.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-06 08:01:07 +02:00
Daniel Vetter
d9e55608cd drm/i915: introduce struct intel_set_config
intel_crtc_set_config is an unwidly beast and is in serious need of
some function extraction. To facilitate that, introduce a struct to
keep track of all the state involved. Atm it doesn't do much more than
keep track of all the allocated memory.

v2: Apply some bikeshed to intel_set_config_free, as suggested by
Jesse Barnes.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-06 08:00:32 +02:00
Daniel Vetter
24e804ba97 drm/i915: rip out intel_dp->dpms_mode
We now track the connector state in encoder->connectors_active, and
because the DP output can't be cloned, that is sufficient to track the
link state. Hence use this instead of adding yet another modeset state
variable with dubious semantics at driver load and resume time.

Also, connectors_active should only ever be set when the encoder is
linked to a crtc, hence convert that crtc test into a WARN.

v2: Rebase on top of struct intel_dp moving.

v3: The rebase accidentally killed the newly-introduced intel_dp->port
Noticed by Paulo Zanoni.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-06 08:00:05 +02:00
Daniel Vetter
84bb65bded drm/i915: rip out intel_crtc->dpms_mode
Afaict this has been used for two things:
- To prevent the crtc enable code from being run twice. We have now
  intel_crtc->active to track this in a more precise way.
- To ensure the code copes correctly with the unknown hw state after
  boot and resume. Thanks to the hw state readout and sanitize code we
  have now a better way to handle this.

The only thing it still does is complicate our modeset state space.

Having outlived its usefullness, let it just die.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-06 08:00:00 +02:00
Daniel Vetter
0a91ca2921 drm/i915: check connector hw/sw state
Atm we can only check the connector state after a dpms call - while
doing modeset with the copy&pasted crtc helper code things are too
ill-defined for proper checking. But the idea is very much to call
this check from the modeset code, too.

v2: Fix dpms check and don't presume that if the hw isn't on that it
must not be linked up with an encoder (it could simply be switched off
with the dpms state).

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-06 07:59:42 +02:00
Daniel Vetter
85234cdc28 drm/i915/hdmi: implement get_hw_state
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-06 07:58:22 +02:00
Daniel Vetter
f0947c376f drm/i915: Add interfaces to read out encoder/connector hw state
It is all glorious if we try really hard to only enable/disable an
entire display pipe to ensure that everyting happens in the right
order. But if we don't know the output configuration when the driver
takes over, this will all be for vain because we'll make the hw angry
right on the first modeset - we don't know what outputs/ports are
enabled and hence have to disable everything in a rather ad-hoc way.

Hence we need to be able to read out the current hw state, so that we
can properly tear down the current hw state on the first modeset.
Obviously this is also a nice preparation for the fastboot work, where
we try to avoid the modeset on driver load if it matches what the hw
is currently using.

Furthermore we'll be using these functions to cross-check the actual
hw state with what we think it should be, to ensure that the modeset
state machine actually works as advertised.

This patch only contains the interface definitions and a little helper
for the simple case where we have a 1:1 encoder to connector mapping.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-06 07:57:51 +02:00
Daniel Vetter
08a4846969 drm/i915: WARN when trying to enabled an unused crtc
This is the first tiny step towards cross-checking the entire modeset
state machine with WARNs. A crtc can only be enabled when it's
actually in use, i.e. crtc->active imlies crtc->enabled.

Unfortunately we can't (yet) check this when disabling the crtc,
because the crtc helpers are a bit slopy with updating state and
unconditionally update crtc->enabled before changing the hw state.

Fixing that requires quite some more work.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-06 07:57:45 +02:00
Daniel Vetter
c9deac9776 drm/i915: rip out encoder->prepare/commit
With the new infrastructure we're doing this when enabling/disabling
the entire display pipe.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-06 07:57:19 +02:00
Daniel Vetter
a6778b3cfd drm/i915: copy&paste drm_crtc_helper_set_mode
Together with the static helper functions drm_crtc_prepare_encoders
and drm_encoder_disable (which will be simplified in the next patch,
but for now are 1:1 copies). Again, no changes beside new names for
these functions.

Also call our new set_mode instead of the crtc helper one now in all
the places we've done so far.

v2: Call the function just intel_set_mode to better differentia it
from intel_crtc_mode_set which really only does the ->mode_set step of
the entire modeset sequence on one crtc. Whereas this function does
the global change.

Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-06 07:56:54 +02:00
Daniel Vetter
61b77ddda6 drm/i915: clean up encoder_prepare/commit
We no longer need them. And now that all encoders are converted, we
can finally move the cpt modeset check to the right place - at the end
of the crtc_enable function.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-06 07:55:49 +02:00
Daniel Vetter
b2cabb0e1d drm/i915: convert dpms functions of dvo/sdvo/crt
Yeah, big patch but I couldn't come up with a neat idea of how to
split it up further, that wouldn't break dpms on cloned configs
somehow. But the changes in dvo/sdvo/crt are all pretty much
orthonogal, so it's not too bad a patch.

These are the only encoders that support cloning, which requires a few
special changes compared to the previous patches.
- Compute the desired state of the display pipe by walking all
  connected encoders and checking whether any has active connectors.
  To make this clearer, drop the old mode parameter to the crtc dpms
  function and rename it to intel_crtc_update_dpms.
- There's the curious case of intel_crtc->dpms_mode. With the previous
  patches to remove the overlay pipe A code and to rework the load
  detect pipe code, the big users are gone. We still keep it to avoid
  enabling the pipe twice, but we duplicate this logic with
  crtc->active, too. Still, leave this for now and just push a fake
  dpms mode into it that reflects the state of the display pipe.

Changes in the encoder dpms functions:
- We clamp the dpms state to the supported range right away. This is
  escpecially important for the VGA outputs, where only older hw
  supports the intermediate states. This (and the crt->adpa_reg patch)
  allows us to unify the crt dpms code again between all variants
  (gmch, vlv and pch).
- We only enable/disable the output for dvo/sdvo and leave the encoder
  running. The encoder will be disabled/enabled when we switch the
  state of the entire output pipeline (which will happen right away
  for non-cloned setups). This way the duplication is reduced and
  strange interaction when disabling output ports at the wrong time
  avoided.

The dpms code for all three types of connectors contains a bit of
duplicated logic, but I think keeping these special cases separate is
simpler: CRT is the only one that hanldes intermediate dpms state
(which requires extra logic to enable/disable things in the right
order), and introducing some abstraction just to share the code
between dvo and sdvo smells like overkill. We can do that once someone
bothers to implement cloning for the more modern outputs. But I doubt
that this will ever happen.

v2: s/crtc/crt/_set_dpms, noticed by Paulo Zanoni.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-06 07:55:17 +02:00
Daniel Vetter
5ab432ef49 drm/i915/hdmi: convert to encoder->disable/enable
I've picked hdmi as the first encoder to convert because it's rather
simple:
- no cloning possible
- no differences between prepare/commit and dpms off/on switching.

A few changes are required to do so:
- Split up the dpms code into an enable/disable function and wire it
  up with the intel encoder.
- Noop out the existing encoder prepare/commit functions used by the
  crtc helper - our crtc enable/disable code now calls back into the
  encoder enable/disable code at the right spot.
- Create new helper functions to handle dpms changes.
- Add intel_encoder->connectors_active to better track dpms state. Atm
  this is unused, but it will be useful to correctly disable the
  entire display pipe for cloned configurations. Also note that for
  now this is only useful in the dpms code - thanks to the crtc
  helper's dpms confusion across a modeset operation we can't (yet)
  rely on this having a sensible value in all circumstances.
- Rip out the encoder helper dpms callback, if this is still getting
  called somewhere we have a bug. The slight issue with that is that
  the crtc helper abuses dpms off to disable unused functions. Hence
  we also need to implement a default encoder disable function to do
  just that with the new encoder->disable callback.
- Note that we drop the cpt modeset verification in the commit
  callback, too. The right place to do this would be in the crtc's
  enable function, _after_ all the encoders are set up. But because
  not all encoders are converted yet, we can't do that. Hence disable
  this check temporarily as a minor concession to bisectability.

v2: Squash the dpms mode to only the supported values -
connector->dpms is for internal tracking only, we can hence avoid
needless state-changes a bit whithout causing harm.

v3: Apply bikeshed to disable|enable_ddi, suggested by Paulo Zanoni.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-06 07:53:37 +02:00
Daniel Vetter
ef9c3aee60 drm/i915: add direct encoder disable/enable infrastructure
Just prep work, not yet put to some use.

Note that because we're still using the crtc helper to switch modes
(and their complicated way to do partial modesets), we need to call
the encoder's disable function unconditionally.

But once this is cleaned up we shouldn't call the encoder's disable
function unconditionally any more, because then we know that we'll
only call it if the encoder is actually enabled. Also note that we
then need to be careful about which crtc we're filtering the encoder
list on: We want to filter on the crtc of the _current_ mode, not the
one we're about to set up.

For the enabling side we need to do the same trick. And again, we
should be able to simplify this quite a bit when things have settled
into place.

Also note that this simply does not take cloning into account, so dpms
needs to be handled specially for the few outputs where we even bother
with it.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-06 07:53:16 +02:00
Ben Widawsky
0cc2764cc4 drm/i915: use cpu_relax() in wait_for_atomic
As part of the advice given to us from the hardware designers regarding
the maximum wait time on the forcewake handshake we need to move from us
granularity to ms granularity. In earlier patches to do this, Jani
noticed that wait_for_us was properly converted to use cpu_relax(), but
wait_for was not.

The issue has existed since the introduction of the macro:
commit 913d8d1100
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Sat Aug 7 11:01:35 2010 +0100

    drm/i915: Ensure that while(INREG()) are bounded (v2)

CC: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Chris Wilson <chris@chris-wilson.oc.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-03 10:21:29 +02:00
Dave Airlie
65983bd605 Merge branch 'for-airlied' of git://people.freedesktop.org/~danvet/drm-intel into drm-next
Daniel writes:
"New stuff for -next. Highlights:
- prep patches for the modeset rework. Note that one of those patches
  touches the fb helper in the common drm code.
- hasw hdmi audio support (Wang Xingchao)
- improved instdone dumping for gen7 (Ben)
- unbound tracking and a few follow-up patches from Chris
- dma_buf->begin/end_cpu_access plus fix for drm/udl (Dave)
- improve mmio error reporting for hsw
- prep patch for WQ_NON_REENTRANT removal (Tejun Heo)
"

* 'for-airlied' of git://people.freedesktop.org/~danvet/drm-intel: (41 commits)
  drm/i915: Remove __GFP_NO_KSWAPD
  drm/i915: disable rc6 on ilk when vt-d is enabled
  drm/i915: Avoid unbinding due to an interrupted pin_and_fence during execbuffer
  drm/i915: Use new INSTDONE registers (Gen7+)
  drm/i915: Add new INSTDONE registers
  drm/i915: Extract reading INSTDONE
  drm/i915: Use a non-blocking wait for set-to-domain ioctl
  drm/i915: Juggle code order to ease flow of the next patch
  drm/i915: Use cpu relocations if the object is in the GTT but not mappable
  drm/i915: Extract general object init routine
  drm/i915: Protect private gem objects from truncate (such as imported dmabuf)
  drm/i915: Only pwrite through the GTT if there is space in the aperture
  i915: use alloc_ordered_workqueue() instead of explicit UNBOUND w/ max_active = 1
  drm/i915: Find unclaimed MMIO writes.
  drm/i915: Add ERR_INT to gen7 error state
  drm/i915: Cantiga+ cannot handle a hsync front porch of 0
  drm/i915: fix reassignment of variable "intel_dp->DP"
  drm/i915: Try harder to allocate an mmap_offset
  drm/i915: Show pin count in debugfs
  drm/i915: Show (count, size) of purgeable objects in i915_gem_objects
  ...
2012-09-03 12:05:01 +10:00
Dave Airlie
93bb70e0c0 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into drm-next
There was some merge conflicts in -next and they weren't so pretty, so
backmerge now to avoid them.

Conflicts:
	drivers/gpu/drm/i915/i915_gem.c
	drivers/gpu/drm/i915/intel_modes.c
2012-08-27 16:22:20 +10:00
Daniel Vetter
d2434ab7fb drm/i915: drop intel_encoder argument to load_detect_pipe functions
Since it's redundant - we can get the attached encoder in the
functions themselves.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-08-17 10:10:02 +02:00
Jani Nikula
4eab813664 drm/i915: extract connector update from intel_ddc_get_modes() for reuse
Refactor the connector update part of intel_ddc_get_modes() into a separate
intel_connector_update_modes() function for reuse. No functional changes.

Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=45881
Tested-by: Alex Ferrando <alferpal@gmail.com>
Cc: stable@vger.kernel.org (for 3.4+3.5)
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-08-17 09:21:35 +02:00
Daniel Vetter
a22ddff8be Linux 3.6-rc2
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Merge tag 'v3.6-rc2' into drm-intel-next

Backmerge Linux 3.6-rc2 to resolve a few funny conflicts before we put
even more madness on top:

- drivers/gpu/drm/i915/i915_irq.c: Just a spurious WARN removed in
  -fixes, that has been changed in a variable-rename in -next, too.

- drivers/gpu/drm/i915/intel_ringbuffer.c: -next remove scratch_addr
  (since all their users have been extracted in another fucntion),
  -fixes added another user for a hw workaroudn.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-08-17 09:01:08 +02:00
Chris Wilson
bcf9dcc1e6 drm/i915: Workaround hang with BSD and forcewake on SandyBridge
For reasons that are not apparent to anybody, 990bbdadab (drm/i915:
Group the GT routines together in both code and vtable) breaks the use
of the BitStream Decoder ring on SandyBridge. The active ingredient of
that patch is the conversion from a udelay(10) to a udelay(1) in the
busy-wait loop of waiting for the forcewake acknowledge. If we restore
that udelay(10) or insert another udelay(1) afterwards (or any wait
longer than 250ns) everything works again. An alternative is also to
remove any delay from the busy-wait loop.

Given that in the atomic sections we want to complete the wait as quick
as possible to avoid blocking the CPU for too long, it makes sense to
remove the delay altogether and simply spin on the exit condition until
it completes. So we replace the udelay(1) with cpu_relax().

Papers over regression from

commit 990bbdadab
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Mon Jul 2 11:51:02 2012 -0300

    drm/i915: Group the GT routines together in both code and vtable

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=51738
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-08-06 10:43:29 +02:00
Stéphane Marchesin
faea35dd8a drm/i915: Make intel_panel_get_backlight static.
This function isn't used outside of intel_panel.c, so make it static.

Signed-off-by: Stéphane Marchesin <marcheu@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-08-06 08:57:48 +02:00
Daniel Vetter
acbe947550 drm/i915: rip out sanitize_pm again
We believe to have squashed all issues around the gen6+ rps interrupt
generation and why the gpu sometimes got stuck. With that cleared up,
there's no user left for the sanitize_pm infrastructure, so let's just
rip it out.

Note that 'intel_reg_write 0xa014 0x13070000' is the w/a if we find
ourselves stuck again.

Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-07-26 13:37:13 +02:00
Chris Wilson
f047e395dd drm/i915: Avoid concurrent access when marking the device as idle/busy
As suggested by Daniel, rip out the independent timers for device and
crtc busyness and integrate the manual powermanagement of the display
engine into the GEM core and its request tracking. The benefits are that
the code is a lot smaller, fewer moving parts and should fit more neatly
into the overall activity tracking of the driver.

v2: Complete overhaul and removal of the racy timers and workers.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-07-25 18:23:56 +02:00
Paulo Zanoni
ab9d7c302a drm/i915: add port field to struct intel_dp and use it
This will be needed for Haswell, but already has its uses here.

This patch started as a small patch written patch by Shobhit Kumar,
but it has changed so much that none of its original lines remain.

Credits-to: Shobhit Kumar <shobhit.kumar@intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-07-25 18:23:48 +02:00
Daniel Vetter
08d644add0 drm/i915: add port parameter to intel_hdmi_init
Instead of having a giant if cascade to figure this out according to
the passed-in register. We could do quite a bit more cleaning up and
all by using the port at more places, but I think this should be part
of a bigger rework to introduce a struct intel_digital_port which
would keep track of all these things. I guess this will be part of
some haswell-DP-induced refactoring.

For now this rips out the big cascade, which is what annoyed me so
much.

v2: Add port variable name back for the func decl (I've tried to trick
myself below the 80 char limit).

Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-07-25 18:23:47 +02:00
Daniel Vetter
66a9278eec drm/i915: simplify possible_clones computation
Intel hw only has one MUX for encoders, so outputs are either not
cloneable or all in the same group of cloneable outputs. This neatly
simplifies the code and allows us to ditch some ugly if cascades in
the dp and hdmi init code (well, we need these if cascades for other
stuff still, but that can be taken care of in follow-up patches).

Note that this changes two things:
- dvo can now be cloned with sdvo, but dvo is gen2 whereas sdvo is
  gen3+, so no problem. Note that the old code had a bug and didn't
  allow cloning crt with dvo (but only the other way round).
- sdvo-lvds can now be cloned with sdvo-non-tv. Spec says this won't
  work, but the only reason I've found is that you can't use the
  panel-fitter (used for lvds upscaling) with anything else. But we
  don't use the panel fitter for sdvo-lvds. Imo this part of Bspec is
  a) rather confusing b) mostly as a guideline to implementors (i.e.
  explicitly stating what is already implicit from the spec, without
  always going into the details of why). So I think we can ignore this
  - worst case we'll get a bug report from a user with with sdvo-lvds
  and sdvo-tmds and have to add that special case back in.

Because sdvo lvds is a bit special explain in comments why sdvo LVDS
outputs can be cloned, but native LVDS and eDP can't be cloned - we
use the panel fitter for the later, but not for sdvo.

Note that this also uncoditionally initializes the panel_vdd work used
by eDP. Trying to be clever doesn't buy us anything (but strange bugs)
and this way we can kill the is_edp check.

v2: Incorporate review from Paulo
- Add in a missing space.
- Pimp comment message to address his concerns.

Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-07-25 18:23:46 +02:00
Shobhit Kumar
54d63ca660 drm/i915: Move DP structs to shared location
Move the DP structure to shared location so that it can be used from
within the ddi module.

Changes from Paulo:
- Move less code to intel_drv.h
- Remove #include statement
- Replace a tab with a space in train_set

Signed-off-by: Shobhit Kumar <shobhit.kumar@intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-07-25 18:23:45 +02:00
Daniel Vetter
4d678e1670 drm/i915: kill intel_ddc_probe
We have way too much lying hardware to rely on a simple "does someone
answer on the ddc i2c address?" check. And now it's unused, so just
kill it.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-07-20 12:21:39 +02:00
Eugeni Dodonov
0232e927f8 drm/i915: initialize power wells in modeset_init_hw
This initializes power wells within the modeset_init_hw routine.
Testing has shown that this works for both driver load time and for
suspend-resume code paths.

Signed-off-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-07-20 12:21:36 +02:00
Daniel Vetter
e506a0c638 drm/i915: introduce crtc->dspaddr_offset
To avoid recomputing the display framebuffer offset on gen2/3
pageflips. This is also prep work to do similar trickery on gen4+

Also:
- kill "Start", such upper-case remnants from the ddx must surely die.
- rename "Offset" to linear_offset, to make it clearer that on gen4+
  this is only used by the hw for linear buffers, for tiled buffers it
  uses the TILEOFF register.
- call DSAPADDR DSPLINOFF on gen4+ for the same reason (and because
  the documentation really renamed the register).

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-07-05 13:34:14 +02:00
Daniel Vetter
930ebb4624 drm/i915: fix up ilk rc6 disabling confusion
While creating the new enable/disable_gt_powersave functions in

commit 8090c6b9da
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Sun Jun 24 16:42:32 2012 +0200

    drm/i915: wrap up gt powersave enabling functions

I've botched up the handling of ironlake_disable_rc6. Fix this up by
calling it at the right place. Note though that ironlake_disable_rc6
does a bit more than just disabling rc6 - it also tears down all the
allocated context objects.

Hence we need to move intel_teardown_rc6 out and directly call it from
intel_modeset_cleanup.

Also properly mark ironlake_enable_rc6 as static and kill the un-used
declaration in i915_drv.h.

Note: In review a question popped out why disable_rc6 also tears down
the backing object and why we should move that out - it's simply for
consistency with gen6+ rps code, which does it that way.

Cc: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-07-05 09:56:04 +02:00
Eugeni Dodonov
6590190d12 drm/i915: move force wake support into intel_pm
This commit moves force wake support routines into intel_pm modules, and
exports the gen6_gt_check_fifodbg routine (used in I915_READ).

Signed-off-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Acked-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-07-05 09:56:04 +02:00
Daniel Vetter
8090c6b9da drm/i915: wrap up gt powersave enabling functions
... instead of calling each one for each generation indiviudally.

Notice that we've already managed to be inconsistent, the resume path
is missing an IS_VLV check. As a nice benefit we can mark all the
platform specific enable/disable functions as static and hide them in
intel_pm.c

Reviewed-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-06-25 21:07:03 +02:00
Chris Wilson
93314b5b6f drm/i915: Switch off FBC when disabling the primary plane when obscured
As we switch on/off the primary plane if it is completely obscured by an
overlapping video sprite, we also nee to make sure that we update the
FBC configuration at the same time.

v2: Not all crtcs are intel_crtcs, as spotted by Daniel.
v3: Boot testing rules.

References: https://bugs.freedesktop.org/show_bug.cgi?id=50238
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-06-13 20:10:00 +02:00
Daniel Vetter
24ded20442 drm/i915: properly enable the blc controller on the right pipe
On gen4+ we have a bitfield to specify from which pipe the backlight
controller should take it's clock. For PCH split platforms we've
already set these up, but only at initialization time. And without
taking into account the 3rd pipe added with ivb.

For gen4, we've completely ignored these. Although we do restrict lvds
to the 2nd pipe, so this is only a problem on machines where we boot
up with the lvds on the first pipe.

So restructure the code to enable the backlight on the right pipe at
modeset time.

v2: For odd reasons panel_enable_backlight gets called twice in a
modeset, so we can't WARN_ON in there if the backlight controller is
switched on already.

v3: backlight enable can also be called through dpms on, so the check
in there is legit. Update the comment to reflect that.

Tested-By: Kamal Mostafa <kamal@canonical.com>
Bugzilla: https://bugs.launchpad.net/bugs/954661
Cc: Carsten Emde <C.Emde@osadl.org>
Reviewed-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-06-12 19:27:58 +02:00