Commit Graph

340 Commits

Author SHA1 Message Date
Paulo Zanoni 44498aea29 drm/i915: also disable south interrupts when handling them
From the docs:

  "IIR can queue up to two interrupt events. When the IIR is cleared,
  it will set itself again after one clock if a second event was
  stored."

  "Only the rising edge of the PCH Display interrupt will cause the
  North Display IIR (DEIIR) PCH Display Interrupt even bit to be set,
  so all PCH Display Interrupts, including back to back interrupts,
  must be cleared before a new PCH Display interrupt can cause DEIIR
  to be set".

The current code works fine because we don't get many interrupts, but
if we enable the PCH FIFO underrun interrupts we'll start getting so
many interrupts that at some point new PCH interrupts won't cause
DEIIR to be set.

The initial implementation I tried was to turn the code that checks
SDEIIR into a loop, but we can still get interrupts even after the
loop is done (and before the irq handler finishes), so we have to
either disable the interrupts or mask them. In the end I concluded
that just disabling the PCH interrupts is enough, you don't even need
the loop, so this is what this patch implements. I've tested it and it
passes the 2 "PCH FIFO underrun interrupt storms" I can reproduce:
the "ironlake_crtc_disable" case and the "wrong watermarks" case.

In other words, here's how to reproduce the problem fixed by this
patch:
  1 - Enable PCH FIFO underrun interrupts (SERR_INT on SNB+)
  2 - Boot the machine
  3 - While booting we'll get tons of PCH FIFO underrun interrupts
  4 - Plug a new monitor
  5 - Run xrandr, notice it won't detect the new monitor
  6 - Read SDEIIR and notice it's not 0 while DEIIR is 0

Q: Can't we just clear DEIIR before SDEIIR?
A: It doesn't work. SDEIIR has to be completely cleared (including the
interrupts stored on its back queue) before it can flip DEIIR's bit to
1 again, and even while you're clearing it you'll be getting more and
more interrupts.

Q: Why does it work by just disabling+enabling the south interrupts?
A: Because when we re-enable them, if there's something on the SDEIIR
register (maybe an interrupt stored on the queue), the re-enabling
will make DEIIR's bit flip to 1, and since we'll already have
interrupts enabled we'll get another interrupt, then run our irq
handler again to process the "back" interrupts.

v2: Even bigger commit message, added code comments.

Note that this fixes missed dp aux irqs which have been reported for
3.9-rc1. This regression has been introduced by switching to
irq-driven dp aux transactions with

commit 9ee32fea5f
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Sat Dec 1 13:53:48 2012 +0100

    drm/i915: irq-drive the dp aux communication

References: http://www.mail-archive.com/intel-gfx@lists.freedesktop.org/msg18588.html
References: https://lkml.org/lkml/2013/2/26/769
Tested-by: Imre Deak <imre.deak@intel.com>
Reported-by: Sedat Dilek <sedat.dilek@gmail.com>
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
[danvet: Pimp commit message with references for the dp aux irq
timeout regression this fixes.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-03-05 20:06:22 +01:00
Paulo Zanoni d46da43776 drm/i915: add ibx_irq_postinstall
So we can remove duplicated code. Note that this function is used not
only on IBX, but also CPT and LPT.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
[danvet: Also bikeshed s/ironlake_enable_pch_hotplug/ibx_enable_hotplug
to keep consistent with our ibx for pch naming scheme.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-02-15 10:30:38 +01:00
Daniel Vetter 26739f12cf drm/i915: unify HDMI/DP hpd definitions
They're physically the same pins and also the same bits, duplicating
only confuses the reader. This also makes it a bit obvious that we
have quite some code duplication going on here. Squashing that is for
a larger rework in our hpd handling though.

Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-02-15 10:30:37 +01:00
Dave Airlie 6dc1c49da6 Merge branch 'fbcon-locking-fixes' of ssh://people.freedesktop.org/~airlied/linux into drm-next
This pulls in most of Linus tree up to -rc6, this fixes the worst lockdep
reported issues and re-enables fbcon lockdep.

(not the fbcon maintainer)
* 'fbcon-locking-fixes' of ssh://people.freedesktop.org/~airlied/linux: (529 commits)
  Revert "Revert "console: implement lockdep support for console_lock""
  fbcon: fix locking harder
  fb: Yet another band-aid for fixing lockdep mess
  fb: rework locking to fix lock ordering on takeover
2013-02-08 12:10:18 +10:00
Ben Widawsky 2f86f19165 drm/i915: Error state should print /sys/kernel/debug
/sys/kernel/debug has more or less been the standard location of debugfs
for several years now. Other parts of DRM already use this location, so
we should as well.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Carl Worth <cworth@cworth.org>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
[danvet: split up long line.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-31 11:50:04 +01:00
Daniel Vetter 7db0ba242b drm/i915: clarify concurrent hang detect/gpu reset consistency
Damien Lespiau wondered how race the gpu reset/hang detection code is
against concurrent gpu resets/hang detections or combinations thereof.
Luckily the single work item is guranteed to never run concurrently,
so reset handling is already single-threaded.

Hence we only have to worry about concurrent hang detections, or a
hang detection firing off while we're still processing an older gpu
reset request. Due to the new mechanism of setting the reset in
progress flag and the ordering guaranteed by the schedule_work
function there's nothing to do but add a comment explaining why we're
safe.

The only thing I've noticed is that we still try to reset the gpu now,
even when it is declared terminally wedged. Add a check for that to
avoid continous warnings about failed resets, in case the hangcheck
timer ever gets stuck.

Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-21 20:14:59 +01:00
Daniel Vetter f69061bedd drm/i915: create a race-free reset detection
With the previous patch the state transition handling of the reset
code itself is now (hopefully) race free and solid. But that still
leaves out everyone else - with the various lock-free wait paths
we have there's the possibility that the reset happens between the
point where we read the seqno we should wait on and the actual wait.

And if __wait_seqno then never sees the RESET_IN_PROGRESS state, we'll
happily wait for a seqno which will in all likelyhood never signal.

In practice this is not a big problem since the X server gets
constantly interrupted, and can then submit more work (hopefully) to
unblock everyone else: As soon as a new seqno write lands, all waiters
will unblock. But running the i-g-t reset testcase ZZ_hangman can
expose this race, especially on slower hw with fewer cpu cores.

Now looking forward to ARB_robustness and friends that's not the best
possible behaviour, hence this patch adds a reset_counter to be able
to detect any reset, even if a given thread never observed the
in-progress state.

The important part is to correctly order things:
- The write side needs to increment the counter after any seqno gets
  reset.  Hence we need to do that at the end of the reset work, and
  again wake everyone up. We also need to place a barrier in between
  any possible seqno changes and the counter increment, since any
  unlock operations only guarantee that nothing leaks out, but not
  that at later load operation gets moved ahead.
- On the read side we need to ensure that no reset can sneak in and
  invalidate the seqno. In all cases we can use the one-sided barrier
  that unlock operations guarantee (of the lock protecting the
  respective seqno/ring pair) to ensure correct ordering. Hence it is
  sufficient to place the atomic read before the mutex/spin_unlock and
  no additional barriers are required.

The end-result of all this is that we need to wake up everyone twice
in a reset operation:
- First, before the reset starts, to get any lockholders of the locks,
  so that the reset can proceed.
- Second, after the reset is completed, to allow waiters to properly
  and reliably detect the reset condition and bail out.

I admit that this entire reset_counter thing smells a bit like
overkill, but I think it's justified since it makes it really explicit
what the bail-out condition is. And we need a reset counter anyway to
implement ARB_robustness, and imo with finer-grained locking on the
horizont this is the most resilient scheme I could think of.

v2: Drop spurious change in the wait_for_error EXIT_COND - we only
need to wait until we leave the reset-in-progress wedged state.

v3: Don't play tricks with barriers in the throttle ioctl, the
spin_unlock is barrier enough.

I've also considered using a little helper to grab the current
reset_counter, but then decided that hiding the atomic_read isn't a
great idea, since having it explicitly show up in the code is a nice
remainder to reviews to check the memory barriers.

v4: Add a comment to explain why we need to fall through in
__wait_seqno in the end variable assignments.

v5: Review from Damien:
- s/smb/smp/ in a comment
- don't increment the reset counter after we've set it to WEDGED. Now
  we (again) properly wedge the gpu when the reset fails.

Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-21 19:53:54 +01:00
Daniel Vetter 1f83fee08d drm/i915: clear up wedged transitions
We have two important transitions of the wedged state in the current
code:

- 0 -> 1: This means a hang has been detected, and signals to everyone
  that they please get of any locks, so that the reset work item can
  do its job.

- 1 -> 0: The reset handler has completed.

Now the last transition mixes up two states: "Reset completed and
successful" and "Reset failed". To distinguish these two we do some
tricks with the reset completion, but I simply could not convince
myself that this doesn't race under odd circumstances.

Hence split this up, and add a new terminal state indicating that the
hw is gone for good.

Also add explicit #defines for both states, update comments.

v2: Split out the reset handling bugfix for the throttle ioctl.

v3: s/tmp/wedged/ sugested by Chris Wilson. Also fixup up a rebase
error which prevented this patch from actually compiling.

v4: To unify the wedged state with the reset counter, keep the
reset-in-progress state just as a flag. The terminally-wedged state is
now denoted with a big number.

v5: Add a comment to the reset_counter special values explaining that
WEDGED & RESET_IN_PROGRESS needs to be true for the code to be
correct.

v6: Fixup logic errors introduced with the wedged+reset_counter
unification. Since WEDGED implies reset-in-progress (in a way we're
terminally stuck in the dead-but-reset-not-completed state), we need
ensure that we check for this everywhere. The specific bug was in
wait_for_error, which would simply have timed out.

v7: Extract an inline i915_reset_in_progress helper to make the code
more readable. Also annote the reset-in-progress case with an
unlikely, to help the compiler optimize the fastpath. Do the same for
the terminally wedged case with i915_terminally_wedged.

Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-20 13:11:16 +01:00
Daniel Vetter 33196dedda drm/i915: move wedged to the other gpu error handling stuff
And to make Ben Widawsky happier, use the gpu_error instead of
the entire device as the argument in some functions.

Drop the outdated comment on ->wedged for now, a follow-up patch will
change the semantics and add a proper comment again.

Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-20 13:11:15 +01:00
Daniel Vetter 99584db33b drm/i915: extract hangcheck/reset/error_state state into substruct
This has been sprinkled all over the place in dev_priv. I think
it'd be good to also move all the code into a separate file like
i915_gem_error.c, but that's for another patch.

Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-20 13:11:14 +01:00
Ben Widawsky 5d4545aef5 drm/i915: Create a gtt structure
The purpose of the gtt structure is to help isolate our gtt specific
properties from the rest of the code (in doing so it help us finish the
isolation from the AGP connection).

The following members are pulled out (and renamed):
gtt_start
gtt_total
gtt_mappable_end
gtt_mappable
gtt_base_addr
gsm

The gtt structure will serve as a nice place to put gen specific gtt
routines in upcoming patches. As far as what else I feel belongs in this
structure: it is meant to encapsulate the GTT's physical properties.
This is why I've not added fields which track various drm_mm properties,
or things like gtt_mtrr (which is itself a pretty transient field).

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
[Ben modified commit messages]
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-17 22:33:56 +01:00
Egbert Eich af5163acd8 drm/i915: Remove pch_rq_mask from struct drm_i915_private.
This variable is only used locally in the irq postinstall
functions for ivybridge and ironlake.

Signed-off-by: Egbert Eich <eich@suse.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-17 22:07:52 +01:00
Dave Airlie b5cc6c0387 Merge tag 'drm-intel-next-2012-12-21' of git://people.freedesktop.org/~danvet/drm-intel into drm-next
Daniel writes:
- seqno wrap fixes and debug infrastructure from Mika Kuoppala and Chris
  Wilson
- some leftover kill-agp on gen6+ patches from Ben
- hotplug improvements from Damien
- clear fb when allocated from stolen, avoids dirt on the fbcon (Chris)
- Stolen mem support from Chris Wilson, one of the many steps to get to
  real fastboot support.
- Some DDI code cleanups from Paulo.
- Some refactorings around lvds and dp code.
- some random little bits&pieces

* tag 'drm-intel-next-2012-12-21' of git://people.freedesktop.org/~danvet/drm-intel: (93 commits)
  drm/i915: Return the real error code from intel_set_mode()
  drm/i915: Make GSM void
  drm/i915: Move GSM mapping into dev_priv
  drm/i915: Move even more gtt code to i915_gem_gtt
  drm/i915: Make next_seqno debugs entry to use i915_gem_set_seqno
  drm/i915: Introduce i915_gem_set_seqno()
  drm/i915: Always clear semaphore mboxes on seqno wrap
  drm/i915: Initialize hardware semaphore state on ring init
  drm/i915: Introduce ring set_seqno
  drm/i915: Missed conversion to gtt_pte_t
  drm/i915: Bug on unsupported swizzled platforms
  drm/i915: BUG() if fences are used on unsupported platform
  drm/i915: fixup overlay stolen memory leak
  drm/i915: clean up PIPECONF bpc #defines
  drm/i915: add intel_dp_set_signal_levels
  drm/i915: remove leftover display.update_wm assignment
  drm/i915: check for the PCH when setting pch_transcoder
  drm/i915: Clear the stolen fb before enabling
  drm/i915: Access to snooped system memory through the GTT is incoherent
  drm/i915: Remove stale comment about intel_dp_detect()
  ...

Conflicts:
	drivers/gpu/drm/i915/intel_display.c
2013-01-17 20:34:08 +10:00
Chris Wilson 0f3b6849dd drm/i915: Record DERRMR, FORCEWAKE and RING_CTL in error-state
These are useful for investigating hangs involving WAIT_FOR_EVENT.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
[danvet: Apply a droplet of Future-Proof in the if-ladder.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-15 13:34:57 +01:00
Ben Widawsky 7dbf9d6e0f drm/i915: BUG() if fences are used on unsupported platform
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-18 22:29:55 +01:00
Daniel Vetter b45305fce5 drm/i915: Implement workaround for broken CS tlb on i830/845
Now that Chris Wilson demonstrated that the key for stability on early
gen 2 is to simple _never_ exchange the physical backing storage of
batch buffers I've tried a stab at a kernel solution. Doesn't look too
nefarious imho, now that I don't try to be too clever for my own good
any more.

v2: After discussing the various techniques, we've decided to always blit
batches on the suspect devices, but allow userspace to opt out of the
kernel workaround assume full responsibility for providing coherent
batches. The principal reason is that avoiding the blit does improve
performance in a few key microbenchmarks and also in cairo-trace
replays.

Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
[danvet:
- Drop the hunk which uses HAS_BROKEN_CS_TLB to implement the ring
  wrap w/a. Suggested by Chris Wilson.
- Also add the ACTHD check from Chris Wilson for the error state
  dumping, so that we still catch batches when userspace opts out of
  the w/a.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-17 17:27:02 +01:00
Daniel Vetter 20afbda209 drm/i915: Fixup hpd irq register setup ordering
For GMCH platforms we set up the hpd irq registers in the irq
postinstall hook. But since we only enable the irq sources we actually
need in PORT_HOTPLUG_EN/STATUS, taking dev_priv->hotplug_supported_mask
into account, no hpd interrupt sources is enabled since

commit 52d7ecedac
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Sat Dec 1 21:03:22 2012 +0100

    drm/i915: reorder setup sequence to have irqs for output setup

Wrongly set-up interrupts also lead to broken hw-based load-detection
on at least GM45, resulting in ghost VGA/TV-out outputs.

To fix this, delay the hotplug register setup until after all outputs
are set up, by moving it into a new dev_priv->display.hpd_irq_callback.
We might also move the PCH_SPLIT platforms to such a setup eventually.

Another funny part is that we need to delay the fbdev initial config
probing until after the hpd regs are setup, for otherwise it'll detect
ghost outputs. But we can only enable the hpd interrupt handling
itself (and the output polling) _after_ that initial scan, due to
massive locking brain-damage in the fbdev setup code. Add a big
comment to explain this cute little dragon lair.

v2: Encapsulate all the fbdev handling by wrapping the move call into
intel_fbdev_initial_config in intel_fb.c. Requested by Chris Wilson.

v3: Applied bikeshed from Jesse Barnes.

v4: Imre Deak noticed that we also need to call intel_hpd_init after
the drm_irqinstall calls in the gpu reset and resume paths - otherwise
hotplug will be broken. Also improve the comment a bit about why
hpd_init needs to be called before we set up the initial fbdev config.

Bugzilla: Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=54943
Reported-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org> (v3)
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-11 17:22:53 +01:00
Tomas Janousek 97a19a247c drm/i915: don't prevent CPU idle states
Commit 9ee32fea5f unconditionally prevents the CPU from entering idle states
until intel_dp_aux_ch completes for the first time, which never happens on my
DisplayPort-less intel gfx, causing the CPU to get rather hot.

Signed-off-by: Tomas Janousek <tomi@nomi.cz>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-08 18:44:05 +01:00
Chris Wilson e7d841ca03 drm/i915: Close race between processing unpin task and queueing the flip
Before queuing the flip but crucially after attaching the unpin-work to
the crtc, we continue to setup the unpin-work. However, should the
hardware fire early, we see the connected unpin-work and queue the task.
The task then promptly runs and unpins the fb before we finish taking
the required references or even pinning it... Havoc.

To close the race, we use the flip-pending atomic to indicate when the
flip is finally setup and enqueued. So during the flip-done processing,
we can check more accurately whether the flip was expected.

v2: Add the appropriate mb() to ensure that the writes to the page-flip
worker are complete prior to marking it active and emitting the MI_FLIP.
On the read side, the mb should be enforced by the spinlocks.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: stable@vger.kernel.org
[danvet: Review the barriers a bit, we need a write barrier both
before and after updating ->pending. Similarly we need a read barrier
in the interrupt handler both before and after reading ->pending. With
well-ordered irqs only one barrier in each place should be required,
but since this patch explicitly sets out to combat spurious interrupts
with is staged activation of the unpin work we need to go full-bore on
the barriers, too. Discussed with Chris Wilson on irc and changes
acked by him.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-06 14:09:37 +01:00
Paulo Zanoni 36dacf5b8b drm/i915: be less verbose when handling gmbus/aux irqs
Having 9500 lines repeated on dmesg does not help me at all.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-06 13:21:29 +01:00
Daniel Vetter 9ee32fea5f drm/i915: irq-drive the dp aux communication
At least on the platforms that have a dp aux irq and also have it
enabled - vlvhsw should have one, too. But I don't have a machine to
test this on. Judging from docs there's no dp aux interrupt for gm45.

Also, I only have an ivb cpu edp machine, so the dp aux A code for
snb/ilk is untested.

For dpcd probing when nothing is connected it slashes about 5ms of cpu
time (cpu time is now negligible), which agrees with 3 * 5 400 usec
timeouts.

A previous version of this patch increases the time required to go
through the dp_detect cycle (which includes reading the edid) from
around 33 ms to around 40 ms. Experiments indicated that this is
purely due to the irq latency - the hw doesn't allow us to queue up
dp aux transactions and hence irq latency directly affects throughput.
gmbus is much better, there we have a 8 byte buffer, and we get the
irq once another 4 bytes can be queued up.

But by using the pm_qos interface to request the lowest possible cpu
wake-up latency this slowdown completely disappeared.

Since all our output detection logic is single-threaded with the
mode_config mutex right now anyway, I've decide not ot play fancy and
to just reuse the gmbus wait queue. But this would definitely prep the
way to run dp detection on different ports in parallel

v2: Add a timeout for dp aux transfers when using interrupts - the hw
_does_  prevent this with the hw-based 400 usec timeout, but if the
irq somehow doesn't arrive we're screwed. Lesson learned while
developing this ;-)

v3: While at it also convert the busy-loop to wait_for_atomic, so that
we don't run the risk of an infinite loop any more.

v4: Ensure we have the smallest possible irq latency by using the
pm_qos interface.

v5: Add a comment to the code to explain why we frob pm_qos. Suggested
by Chris Wilson.

v6: Disable dp irq for vlv, that's easier than trying to get at docs
and hw.

v7: Squash in a fix for Haswell that Paulo Zanoni tracked down - the
dp aux registers aren't at a fixed offset any more, but can be on the
PCH while the DP port is on the cpu die.

Reviewed-by: Imre Deak <imre.deak@intel.com> (v6)
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-06 13:18:00 +01:00
Daniel Vetter ce99c2569d drm/i915: wire up do aux channel done interrupt
Doesn't do anything yet than call dp_aux_irq_handler.

Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-06 13:14:38 +01:00
Daniel Vetter 28c70f162a drm/i915: use the gmbus irq for waits
We need two special things to properly wire this up:
- Add another argument to gmbus_wait_hw_status to pass in the
  correct interrupt bit in gmbus4.
- Since we can only get an irq for one of the two events we want,
  hand-roll the wait_event_timeout code so that we wake up every
  jiffie and can check for NAKs. This way we also subsume gmbus
  support for platforms without interrupts (or where those are not
  yet enabled).

The important bit really is to only enable one gmbus interrupt source
at the same time - with that piece of lore figured out, this seems to
work flawlessly.

Ben Widawsky rightfully complained the lack of measurements for the
claimed benefits (especially since the first version was actually
broken and fell back to bit-banging). Previously reading the 256 byte
hdmi EDID takes about 72 ms here. With this patch it's down to 33 ms.
Given that transfering the 256 bytes over i2c at wire speed takes
20.5ms alone, the reduction in additional overhead is rather nice.

v2: Chris Wilson wondered whether GMBUS4 might contain some set bits
when booting up an hence result in some spurious interrupts. Since we
clear GMBUS4 after every wait and we do gmbus transfer really early in
the setup sequence to detect displays the window is small, but still
be paranoid and clear it properly.

v3: Clarify the comment that gmbus irq generation can only support one
kind of event, why it bothers us and how we work around that limit.

Cc: Daniel Kurtz <djkurtz@chromium.org>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-06 13:14:37 +01:00
Daniel Vetter 515ac2bb95 drm/i915: wire up gmbus irq handler
Only enables the interrupt and puts a irq handler into place, doesn't
do anything yet.

Unfortunately there's no gmbus interrupt support for gen2/3 (safe for
pnv, but there the irq is marked as "Test mode").

v2: Wire up the irq handler for vlv and gen4 properly.

v3: i915_enable_pipestat expects the mask bit, not the status bits ... and
for added hilarity those are rather inconsistently named.

Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-06 13:14:37 +01:00
Daniel Vetter 52d7ecedac drm/i915: reorder setup sequence to have irqs for output setup
Otherwise the new&shiny irq-driven gmbus and dp aux code won't work that
well. Noticed since the dp aux code doesn't have an automatic fallback
with a timeout (since the hw provides for that already).

v2: Simple move drm_irq_install before intel_modeset_gem_init, as
suggested by Ben Widawsky.

v3: Now that interrupts are enabled before all connectors are fully
set up, we might fall over serving a HPD interrupt while things are
still being set up. Instead of jumping through massive hoops and
complicating the code with a separate hpd irq enable step, simply
block out the hotplug work item from doing anything until things are
in place.

v4: Actually, we can enable hotplug processing only after the fbdev is
fully set up, since we call down into the fbdev from the hotplug work
functions. So stick the hpd enabling right next to the poll helper
initialization.

v5: We need to enable irqs before intel_modeset_init, since that
function sets up the outputs.

v6: Fixup cleanup sequence, too.

Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-06 13:14:36 +01:00
Daniel Vetter 61bac78e03 drm/i915: setup the hangcheck timer early
... together with all the other irq related resources in
intel_irq_init. I've managed to oops in the notify_ring function on my
ilk, presumably because of the powerctx setup call to i915_gpu_idle.

Note that this is only a problem with the reorder irq setup sequence
for irq-driver gmbus/dp aux.

Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-06 13:14:35 +01:00
Daniel Vetter d83779a9cb drm/i915: don't handle PIPE_LEGACY_BLC_EVENT_STATUS on vlv
This is for legacy legacy stuff, and checking with the leftover
pipe from the previous loop is propably not what we want. Since
pipe == 2 after the loop ... Then we only assing a variable and do
nothing with it.

Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-06 13:14:35 +01:00
Daniel Vetter 4a06e201da drm/i915: haswell has the same irq handlers as ivb
No need to have the exaxt same code twice.

Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-06 13:14:35 +01:00
Daniel Vetter 1a240d4de2 drm/i915: fixup sparse warnings
- __iomem where there is none (I love how we mix these things up).
- Use gfp_t instead of an other plain type.
- Unconfuse one place about enum pipe vs enum transcoder - for the pch
  transcoder we actually use the pipe enum. Fixup the other cases
  where we assign the pipe to the cpu transcoder with explicit casts.
- Declare the mch_lock properly in a header.

There is still a decent mess in intel_bios.c about __iomem, but heck,
this is x86 and we're allowed to do that.

Makes-sparse-happy: Chris Wilson <chris@chris-wilson.co.uk>
[danvet: Use a space after the cast consistently and fix up the
newly-added cast in i915_irq.c to properly use __iomem.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-12-03 22:31:04 +01:00
Chris Wilson 960e3564bf drm/i915: Support readback of stolen objects upon error
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-11-30 23:32:22 +01:00
Daniel Vetter acd15b6cc2 drm/i915: optimize ilk/snb irq handler
We only need to read/write the south interrupt register if the
corresponding bit is set in the north master interrupt register.
Noticed while reading our interrupt handling code.

Same optimization has already been applied on ivb in

commit 0e43406bcc
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Wed May 9 21:45:44 2012 +0100

    drm/i915: Simplify interrupt processing for IvyBridge

    We can take advantage that the PCH_IIR is a subordinate register to
    reduce one of the required IIR reads, and that we only need to clear
    interrupts handled to reduce the writes. And by simply tidying the code
    we can reduce the line count and hopefully make it more readable.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-11-30 19:06:33 +01:00
Chris Wilson df2b23d979 drm/i915: Include the last semaphore sync point in the error-state
Should be useful to know what the driver thought the other ring's seqno
was when it last used a semaphore.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-11-29 11:43:54 +01:00
Jesse Barnes 4fc688ce79 drm/i915: protect RPS/RC6 related accesses (including PCU) with a new mutex
This allows the power related code to run independently of the rest of
the pipeline, extending the resume and init time improvements into
userspace, which would otherwise have been blocked on the struct mutex
if we were doing PCU communication.

v2: Also convert the locking for the rps sysfs interface.

Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> (v1)
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-11-11 23:51:41 +01:00
Daniel Vetter a4da4fa4e5 drm/i915: extract l3_parity substruct from dev_priv
Pretty astonishing how far apart these two members landed ... Especially since
I've already removed almost 200 lines in between.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-11-11 23:51:40 +01:00
Paulo Zanoni fe2b8f9dfb drm/i915: convert pipe timing definitions to transcoder
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-10-26 10:24:49 +02:00
Paulo Zanoni 702e7a56af drm/i915: convert PIPECONF to use transcoder instead of pipe
Because the PIPECONF register is actually part of the CPU transcoder,
not the CPU pipe.

Ideally we would also rename PIPECONF to TRANSCONF to remind people
that they should use the transcoder instead of the pipe, but let's
keep it like this for now since most Gens still name it PIPECONF.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-10-26 10:24:47 +02:00
Daniel Vetter c2fb791692 Linux 3.7-rc2
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Merge tag 'v3.7-rc2' into drm-intel-next-queued

Linux 3.7-rc2

Backmerge to solve two ugly conflicts:
- uapi. We've already added new ioctl definitions for -next. Do I need to say more?
- wc support gtt ptes. We've had to revert this for snb+ for 3.7 and
  also fix a few other things in the code. Now we know how to make it
  work on snb+, but to avoid losing the other fixes do the backmerge
  first before re-enabling wc gtt ptes on snb+.

And a few other minor things, among them git getting confused in
intel_dp.c and seemingly causing a conflict out of nothing ...

Conflicts:
	drivers/gpu/drm/i915/i915_reg.h
	drivers/gpu/drm/i915/intel_display.c
	drivers/gpu/drm/i915/intel_dp.c
	drivers/gpu/drm/i915/intel_modes.c
	include/drm/i915_drm.h

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-10-22 14:34:51 +02:00
Daniel Vetter 76e4383034 drm/i915: move hpd handling to (ibx|cpt)_irq_handler
Somehow this was left out in the refactoring that introduced the pch
handlers. Avoids a hotplug_mask special case in the ilk_irq_handler.

Noticed while hunting down the pch hotplug bits.

Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-10-17 21:06:57 +02:00
Chris Wilson cecc21fea9 drm/i915: Align the hangcheck wakeup to the nearest second
round_jiffies() aligns the wakeup time to the nearest second in order to
batch wakeups and reduce system load, which is useful for unimportant
coarse timers like our hangcheck.

v2: round_jiffies_relative() returns the relative jiffie value, whereas
we need the absolute value for the timer.

Suggested-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-10-08 18:44:36 +02:00
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
Daniel Vetter 74d44445af drm/i915: call drm_handle_vblank before finish_page_flip
... since finish_page_flip needs the vblank timestamp generated
in drm_handle_vblank. Somehow all the gmch platforms get it right,
but all the pch platform irq handlers get is wrong. Hooray for copy&
pasting!

Currently this gets papered over by a gross hack in finish_page_flip.
A second patch will remove that.

Note that without this, the new timestamp sanity checks in flip_test
occasionally get tripped up, hence the cc: stable tag.

Cc: stable@vger.kernel.org
Reviewed-by: mario.kleiner@tuebingen.mpg.de
Tested-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-10-04 10:33:43 +02:00
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
David Howells 4126d5d61f UAPI: (Scripted) Remove redundant DRM UAPI header #inclusions from drivers/gpu/.
Remove redundant DRM UAPI header #inclusions from drivers/gpu/.

Remove redundant #inclusions of core DRM UAPI headers (drm.h, drm_mode.h and
drm_sarea.h).  They are now #included via drmP.h and drm_crtc.h via a preceding
patch.

Without this patch and the patch to make include the UAPI headers from the core
headers, after the UAPI split, the DRM C sources cannot find these UAPI headers
because the DRM code relies on specific -I flags to make #include "..."  work
on headers in include/drm/ - but that does not work after the UAPI split without
adding more -I flags.

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 18:01:05 +01:00
Daniel Vetter ff1f525ef4 drm/i915: s/DRM_IRQ_ARGS/int irq, void *arg
I'm official fed up with the yelling and useless indirection.

Let it burn!

Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-10-02 17:58:21 +02:00
Vijay Purushothaman ae33cdcfc6 drm/i915: Fix SDVO IER and status bits for Valleyview
Fixed SDVOB and SDVOC bit definitions for Valleyview.

Signed-off-by: Vijay Purushothaman <vijay.a.purushothaman@intel.com>
Signed-off-by: Ben Widawsky <benjamin.widawsky@intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-28 16:46:55 +02:00
Jesse Barnes 3bcedbe5f2 drm/i915: limit VLV IRQ enables to those we use
To match IVB.

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-26 16:16:32 +02:00
Daniel Vetter 398b7a1b88 Linux 3.6-rc7
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Merge tag 'v3.6-rc7' into drm-intel-next-queued

Manual backmerge of -rc7 to resolve a silent conflict leading to
compile failure in drivers/gpu/drm/i915/intel_hdmi.c.

This is due to the bugfix in -rc7:

commit b98b601672
Author: Wang Xingchao <xingchao.wang@intel.com>
Date:   Thu Sep 13 07:43:22 2012 +0800

    drm/i915: HDMI - Clear Audio Enable bit for Hot Plug

Since this code moved around a lot in -next git put that snippet at
the wrong spot. I've tried to fix this by making the conflict explicit
by merging a version for next with:

commit 3cce574f01
Author: Wang Xingchao <xingchao.wang@intel.com>
Date:   Thu Sep 13 11:19:00 2012 +0800

    drm/i915: HDMI - Clear Audio Enable bit for Hot Plug unconditionally

But that failed to solve the entire problem. To avoid pushing out
further -nightly branch to our QA where this is broken, do the
backmerge and manually add the stuff git adds to -next from the patch
in -fixes.

Note that this doesn't show up in git's merge diff (and hence is also
not handled by git rerere), which adds to the reasons why I'd like to
fix this with a verbose backmerge. The git merge diff only shows a
bunch of trivial conflicts of the "code changed in lines next to each
another" kind.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-24 18:17:12 +02:00
Ben Widawsky 792496368b drm/i915: Error checks in gen6_set_rps
With the new "standardized" sysfs interfaces we need to be a bit more
careful about setting the RPS values.

Because the sysfs code and the rps workqueue can run at the same time,
if the sysfs setter wins the race to the mutex, the workqueue can come
in and set a value which is out of range (ie. we're no longer protecting
by RPINTLIM).

I was not able to actually make this error occur in testing.

Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-20 14:23:01 +02:00
Chris Wilson 9da3da660d drm/i915: Replace the array of pages with a scatterlist
Rather than have multiple data structures for describing our page layout
in conjunction with the array of pages, we can migrate all users over to
a scatterlist.

One major advantage, other than unifying the page tracking structures,
this offers is that we replace the vmalloc'ed array (which can be up to
a megabyte in size) with a chain of individual pages which helps reduce
memory pressure.

The disadvantage is that we then do not have a simple array to iterate,
or to access randomly. The common case for this is in the relocation
processing, which will typically fit within a single scatterlist page
and so be almost the same cost as the simple array. For iterating over
the array, the extra function call could be optimised away, but in
reality is an insignificant cost of either binding the pages, or
performing the pwrite/pread.

v2: Fix drm_clflush_sg() to not invoke wbinvd as well! And fix the
trivial compile error from rebasing.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-20 14:22:57 +02:00