After applying wait-boost we often find ourselves stuck at higher clocks
than required. The current threshold value requires the GPU to be
continuously and completely idle for 313ms before it is dropped by one
bin. Conversely, we require the GPU to be busy for an average of 90% over
a 84ms period before we upclock. So the current thresholds almost never
downclock the GPU, and respond very slowly to sudden demands for more
power. It is easy to observe that we currently lock into the wrong bin
and both underperform in benchmarks and consume more power than optimal
(just by repeating the task and measuring the different results).
An alternative approach, as discussed in the bspec, is to use a
continuous threshold for upclocking, and an average value for downclocking.
This is good for quickly detecting and reacting to state changes within a
frame, however it fails with the common throttling method of waiting
upon the outstanding frame - at least it is difficult to choose a
threshold that works well at 15,000fps and at 60fps. So continue to use
average busy/idle loads to determine frequency change.
v2: Use 3 power zones to keep frequencies low in steady-state mostly
idle (e.g. scrolling, interactive 2D drawing), and frequencies high
for demanding games. In between those end-states, we use a
fast-reclocking algorithm to converge more quickly on the desired bin.
v3: Bug fixes - make sure we reset adj after switching power zones.
v4: Tune - drop the continuous busy thresholds as it prevents us from
choosing the right frequency for glxgears style swap benchmarks. Instead
the goal is to be able to find the right clocks irrespective of the
wait-boost.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Kenneth Graunke <kenneth@whitecape.org>
Cc: Stéphane Marchesin <stephane.marchesin@gmail.com>
Cc: Owen Taylor <otaylor@redhat.com>
Cc: "Meng, Mengmeng" <mengmeng.meng@intel.com>
Cc: "Zhuang, Lena" <lena.zhuang@intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
If we encounter a situation where the CPU blocks waiting for results
from the GPU, give the GPU a kick to boost its the frequency.
This should work to reduce user interface stalls and to quickly promote
mesa to high frequencies - but the cost is that our requested frequency
stalls high (as we do not idle for long enough before rc6 to start
reducing frequencies, nor are we aggressive at down clocking an
underused GPU). However, this should be mitigated by rc6 itself powering
off the GPU when idle, and that energy use is dependent upon the workload
of the GPU in addition to its frequency (e.g. the math or sampler
functions only consume power when used). Still, this is likely to
adversely affect light workloads.
In particular, this nearly eliminates the highly noticeable wake-up lag
in animations from idle. For example, expose or workspace transitions.
(However, given the situation where we fail to downclock, our requested
frequency is almost always the maximum, except for Baytrail where we
manually downclock upon idling. This often masks the latency of
upclocking after being idle, so animations are typically smooth - at the
cost of increased power consumption.)
Stéphane raised the concern that this will punish good applications and
reward bad applications - but due to the nature of how mesa performs its
client throttling, I believe all mesa applications will be roughly
equally affected. To address this concern, and to prevent applications
like compositors from permanently boosting the RPS state, we ratelimit the
frequency of the wait-boosts each client recieves.
Unfortunately, this techinique is ineffective with Ironlake - which also
has dynamic render power states and suffers just as dramatically. For
Ironlake, the thermal/power headroom is shared with the CPU through
Intelligent Power Sharing and the intel-ips module. This leaves us with
no GPU boost frequencies available when coming out of idle, and due to
hardware limitations we cannot change the arbitration between the CPU and
GPU quickly enough to be effective.
v2: Limit each client to receiving a single boost for each active period.
Tested by QA to only marginally increase power, and to demonstrably
increase throughput in games. No latency measurements yet.
v3: Cater for front-buffer rendering with manual throttling.
v4: Tidy up.
v5: Sadly the compositor needs frequent boosts as it may never idle, but
due to its picking mechanism (using ReadPixels) may require frequent
waits. Those waits, along with the waits for the vrefresh swap, conspire
to keep the GPU at low frequencies despite the interactive latency. To
overcome this we ditch the one-boost-per-active-period and just ratelimit
the number of wait-boosts each client can receive.
Reported-and-tested-by: Paul Neumann <paul104x@yahoo.de>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=68716
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Kenneth Graunke <kenneth@whitecape.org>
Cc: Stéphane Marchesin <stephane.marchesin@gmail.com>
Cc: Owen Taylor <otaylor@redhat.com>
Cc: "Meng, Mengmeng" <mengmeng.meng@intel.com>
Cc: "Zhuang, Lena" <lena.zhuang@intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
[danvet: No extern for function prototypes in headers.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
When we switched to always using a timeout in conjunction with
wait_seqno, we lost the ability to detect missed interrupts. Since, we
have had issues with interrupts on a number of generations, and they are
required to be delivered in a timely fashion for a smooth UX, it is
important that we do log errors found in the wild and prevent the
display stalling for upwards of 1s every time the seqno interrupt is
missed.
Rather than continue to fix up the timeouts to work around the interface
impedence in wait_event_*(), open code the combination of
wait_event[_interruptible][_timeout], and use the exposed timer to
poll for seqno should we detect a lost interrupt.
v2: In order to satisfy the debug requirement of logging missed
interrupts with the real world requirments of making machines work even
if interrupts are hosed, we revert to polling after detecting a missed
interrupt.
v3: Throw in a debugfs interface to simulate broken hw not reporting
interrupts.
v4: s/EGAIN/EAGAIN/ (Imre)
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Imre Deak <imre.deak@intel.com>
[danvet: Don't use the struct typedef in new code.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We only wish to know the value of seqno when emitting the tracepoint, so
move the query from a parameter to the macro to inside the conditional
macro body so that the query is only evaluated when required.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
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Merge tag 'v3.12-rc2' into drm-intel-next
Backmerge Linux 3.12-rc2 to prep for a bunch of -next patches:
- Header cleanup in intel_drv.h, both changed in -fixes and my current
-next pile.
- Cursor handling cleanup for -next which depends upon the cursor
handling fix merged into -rc2.
All just trivial conflicts of the "changed adjacent lines" type:
drivers/gpu/drm/i915/i915_gem.c
drivers/gpu/drm/i915/intel_display.c
drivers/gpu/drm/i915/intel_drv.h
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We currently disable the ERR_INT interrupts while running the IRQ
handler because we fear that if we do an unclaimed register access
from inside the IRQ handler we'll keep triggering the IRQ handler
forever.
The problem is that since we always disable the ERR_INT interrupts at
the IRQ handler, when we get a FIFO underrun we'll always print both
messages:
- "uncleared fifo underrun on pipe A"
- "Pipe A FIFO underrun"
Because the "was_enabled" variable from
ivybridge_set_fifo_underrun_reporting will always be false (since we
disable ERR int at the IRQ handler!).
Instead of actually fixing ivybridge_set_fifo_underrun_reporting,
let's just remove the "disable ERR_INT during the IRQ handler" code.
As far as we know we shouldn't really be triggering ERR_INT interrupts
from the IRQ handler, so if we ever get stuck in the endless loop of
interrupts we can git-bisect and revert (and we can even bisect and
revert this patch in case I'm just wrong). As a bonus, our IRQ handler
is now simpler and a few nanoseconds faster.
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We'd only ever used this define to denote whether or not we have the
dynamic parity feature (DPF) and never to determine whether or not L3
exists. Baytrail is a good example of where L3 exists, and not DPF.
This patch provides clarify in the code for future use cases which might
want to actually query whether or not L3 exists.
v2: Add /* DPF == dynamic parity feature */
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Certain HSW SKUs have a second bank of L3. This L3 remapping has a
separate register set, and interrupt from the first "slice". A slice is
simply a term to define some subset of the GPU's l3 cache. This patch
implements both the interrupt handler, and ability to communicate with
userspace about this second slice.
v2: Remove redundant check about non-existent slice.
Change warning about interrupts of unknown slices to WARN_ON_ONCE
Handle the case where we get 2 slice interrupts concurrently, and switch
the tracking of interrupts to be non-destructive (all Ville)
Don't enable/mask the second slice parity interrupt for ivb/vlv (even
though all docs I can find claim it's rsvd) (Ville + Bryan)
Keep BYT excluded from L3 parity
v3: Fix the slice = ffs to be decremented by one (found by Ville). When
I initially did my testing on the series, I was using 1-based slice
counting, so this code was correct. Not sure why my simpler tests that
I've been running since then didn't pick it up sooner.
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This reduces dmesg noise when there's a glitch on the hpd line, or there
are more than one connectors on the same hpd line and only one of them
changes.
While at it, switch to use the friendly status names instead of numbers.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
My g33 here seems to be shockingly good at hitting them all. This time
around kms_flip/flip-vs-panning-vs-hang blows up:
intel_crtc_wait_for_pending_flips correctly checks for gpu hangs and
if a gpu hang is pending aborts the wait for outstanding flips so that
the setcrtc call will succeed and release the crtc mutex. And the gpu
hang handler needs that lock in intel_display_handle_reset to be able
to complete outstanding flips.
The problem is that we can race in two ways:
- Waiters on the dev_priv->pending_flip_queue aren't woken up after
we've the reset as pending, but before we actually start the reset
work. This means that the waiter doesn't notice the pending reset
and hence will keep on hogging the locks.
Like with dev->struct_mutex and the ring->irq_queue wait queues we
there need to wake up everyone that potentially holds a lock which
the reset handler needs.
- intel_display_handle_reset was called _after_ we've already
signalled the completion of the reset work. Which means a waiter
could sneak in, grab the lock and never release it (since the
pageflips won't ever get released).
Similar to resetting the gem state all the reset work must complete
before we update the reset counter. Contrary to the gem reset we
don't need to have a second explicit wake up call since that will
have happened already when completing the pageflips. We also don't
have any issues that the completion happens while the reset state is
still pending - wait_for_pending_flips is only there to ensure we
display the right frame. After a gpu hang&reset events such
guarantees are out the window anyway. This is in contrast to the gem
code where too-early wake-up would result in unnecessary restarting
of ioctls.
Also, since we've gotten these various deadlocks and ordering
constraints wrong so often throw copious amounts of comments at the
code.
This deadlock regression has been introduced in the commit which added
the pageflip reset logic to the gpu hang work:
commit 96a02917a0
Author: Ville Syrjälä <ville.syrjala@linux.intel.com>
Date: Mon Feb 18 19:08:49 2013 +0200
drm/i915: Finish page flips and update primary planes after a GPU reset
v2:
- Add comments to explain how the wake_up serves as memory barriers
for the atomic_t reset counter.
- Improve the comments a bit as suggested by Chris Wilson.
- Extract the wake_up calls before/after the reset into a little
i915_error_wake_up and unconditionally wake up the
pending_flip_queue waiters, again as suggested by Chris Wilson.
v3: Throw copious amounts of comments at i915_error_wake_up as
suggested by Chris Wilson.
Cc: stable@vger.kernel.org
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Score and action reveals what all the rings were doing
and why hang was declared. Add idle state so that
we can distinguish between waiting and idle ring.
v2: - add idle as a hangcheck action
- consensed hangcheck status to single line (Chris)
- mark active explicitly when we are making progress (Chris)
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Since we've started to clean up pending flips when the gpu hangs in
commit 96a02917a0
Author: Ville Syrjälä <ville.syrjala@linux.intel.com>
Date: Mon Feb 18 19:08:49 2013 +0200
drm/i915: Finish page flips and update primary planes after a GPU reset
the gpu reset work now also grabs modeset locks. But since work items
on our private work queue are not allowed to do that due to the
flush_workqueue from the pageflip code this results in a neat
deadlock:
INFO: task kms_flip:14676 blocked for more than 120 seconds.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kms_flip D ffff88019283a5c0 0 14676 13344 0x00000004
ffff88018e62dbf8 0000000000000046 ffff88013bdb12e0 ffff88018e62dfd8
ffff88018e62dfd8 00000000001d3b00 ffff88019283a5c0 ffff88018ec21000
ffff88018f693f00 ffff88018eece000 ffff88018e62dd60 ffff88018eece898
Call Trace:
[<ffffffff8138ee7b>] schedule+0x60/0x62
[<ffffffffa046c0dd>] intel_crtc_wait_for_pending_flips+0xb2/0x114 [i915]
[<ffffffff81050ff4>] ? finish_wait+0x60/0x60
[<ffffffffa0478041>] intel_crtc_set_config+0x7f3/0x81e [i915]
[<ffffffffa031780a>] drm_mode_set_config_internal+0x4f/0xc6 [drm]
[<ffffffffa0319cf3>] drm_mode_setcrtc+0x44d/0x4f9 [drm]
[<ffffffff810e44da>] ? might_fault+0x38/0x86
[<ffffffffa030d51f>] drm_ioctl+0x2f9/0x447 [drm]
[<ffffffff8107a722>] ? trace_hardirqs_off+0xd/0xf
[<ffffffffa03198a6>] ? drm_mode_setplane+0x343/0x343 [drm]
[<ffffffff8112222f>] ? mntput_no_expire+0x3e/0x13d
[<ffffffff81117f33>] vfs_ioctl+0x18/0x34
[<ffffffff81118776>] do_vfs_ioctl+0x396/0x454
[<ffffffff81396b37>] ? sysret_check+0x1b/0x56
[<ffffffff81118886>] SyS_ioctl+0x52/0x7d
[<ffffffff81396b12>] system_call_fastpath+0x16/0x1b
2 locks held by kms_flip/14676:
#0: (&dev->mode_config.mutex){+.+.+.}, at: [<ffffffffa0316545>] drm_modeset_lock_all+0x22/0x59 [drm]
#1: (&crtc->mutex){+.+.+.}, at: [<ffffffffa031656b>] drm_modeset_lock_all+0x48/0x59 [drm]
INFO: task kworker/u8:4:175 blocked for more than 120 seconds.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/u8:4 D ffff88018de9a5c0 0 175 2 0x00000000
Workqueue: i915 i915_error_work_func [i915]
ffff88018e37dc30 0000000000000046 ffff8801938ab8a0 ffff88018e37dfd8
ffff88018e37dfd8 00000000001d3b00 ffff88018de9a5c0 ffff88018ec21018
0000000000000246 ffff88018e37dca0 000000005a865a86 ffff88018de9a5c0
Call Trace:
[<ffffffff8138ee7b>] schedule+0x60/0x62
[<ffffffff8138f23d>] schedule_preempt_disabled+0x9/0xb
[<ffffffff8138d0cd>] mutex_lock_nested+0x205/0x3b1
[<ffffffffa0477094>] ? intel_display_handle_reset+0x7e/0xbd [i915]
[<ffffffffa0477094>] ? intel_display_handle_reset+0x7e/0xbd [i915]
[<ffffffffa0477094>] intel_display_handle_reset+0x7e/0xbd [i915]
[<ffffffffa044e0a2>] i915_error_work_func+0x128/0x147 [i915]
[<ffffffff8104a89a>] process_one_work+0x1d4/0x35a
[<ffffffff8104a821>] ? process_one_work+0x15b/0x35a
[<ffffffff8104b4a5>] worker_thread+0x144/0x1f0
[<ffffffff8104b361>] ? rescuer_thread+0x275/0x275
[<ffffffff8105076d>] kthread+0xac/0xb4
[<ffffffff81059d30>] ? finish_task_switch+0x3b/0xc0
[<ffffffff810506c1>] ? __kthread_parkme+0x60/0x60
[<ffffffff81396a6c>] ret_from_fork+0x7c/0xb0
[<ffffffff810506c1>] ? __kthread_parkme+0x60/0x60
3 locks held by kworker/u8:4/175:
#0: (i915){.+.+.+}, at: [<ffffffff8104a821>] process_one_work+0x15b/0x35a
#1: ((&dev_priv->gpu_error.work)){+.+.+.}, at: [<ffffffff8104a821>] process_one_work+0x15b/0x35a
#2: (&crtc->mutex){+.+.+.}, at: [<ffffffffa0477094>] intel_display_handle_reset+0x7e/0xbd [i915]
This blew up while running kms_flip/flip-vs-panning-vs-hang-interruptible
on one of my older machines.
Unfortunately (despite the proper lockdep annotations for
flush_workqueue) lockdep still doesn't detect this correctly, so we
need to rely on chance to discover these bugs.
Apply the usual bugfix and schedule the reset work on the system
workqueue to keep our own driver workqueue free of any modeset lock
grabbing.
Note that this is not a terribly serious regression since before the
offending commit we'd simply have stalled userspace forever due to
failing to abort all outstanding pageflips.
v2: Add a comment as requested by Chris.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Historically we've run our own driver hotplug handling in our own
work-queue, which then launched the drm core hotplug handling in the
system workqueue. This is important since we flush our own driver
workqueue in the pageflip code while hodling modeset locks, and only
the drm hotplug code grabbed these locks. But with
commit 69787f7da6
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Tue Oct 23 18:23:34 2012 +0000
drm: run the hpd irq event code directly
this was changed and now we could deadlock in our flip handler if
there's a hotplug work blocking the progress of the crucial unpin
works. So this broke the careful deadlock avoidance implemented in
commit b4a98e57fc
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date: Thu Nov 1 09:26:26 2012 +0000
drm/i915: Flush outstanding unpin tasks before pageflipping
Since the rule thus far has been that work items on our own workqueue
may never grab modeset locks simply restore that rule again.
v2: Add a comment to the declaration of dev_priv->wq to warn readers
about the tricky implications of using it. Suggested by Chris Wilson.
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Stuart Abercrombie <sabercrombie@chromium.org>
Reported-by: Stuart Abercrombie <sabercrombie@chromium.org>
References: http://permalink.gmane.org/gmane.comp.freedesktop.xorg.drivers.intel/26239
Cc: stable@vger.kernel.org
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
[danvet: Squash in a comment at the place where we schedule the work.
Requested after-the-fact by Chris on irc since the hpd work isn't the
only place we botch this.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We already have a big splashing *ERROR* for all the relevant cases of
hangs, so this one here is redudant. And it results in an unclean
dmesg when running with simulated hangs. Regression has been
introduced in
commit 05407ff889
Author: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Date: Thu May 30 09:04:29 2013 +0300
drm/i915: detect hang using per ring hangcheck_score
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=68641
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This patch allows PC8+ states on Haswell. These states can only be
reached when all the display outputs are disabled, and they allow some
more power savings.
The fact that the graphics device is allowing PC8+ doesn't mean that
the machine will actually enter PC8+: all the other devices also need
to allow PC8+.
For now this option is disabled by default. You need i915.allow_pc8=1
if you want it.
This patch adds a big comment inside i915_drv.h explaining how it
works and how it tracks things. Read it.
v2: (this is not really v2, many previous versions were already sent,
but they had different names)
- Use the new functions to enable/disable GTIMR and GEN6_PMIMR
- Rename almost all variables and functions to names suggested by
Chris
- More WARNs on the IRQ handling code
- Also disable PC8 when there's GPU work to do (thanks to Ben for
the help on this), so apps can run caster
- Enable PC8 on a delayed work function that is delayed for 5
seconds. This makes sure we only enable PC8+ if we're really
idle
- Make sure we're not in PC8+ when suspending
v3: - WARN if IRQs are disabled on __wait_seqno
- Replace some DRM_ERRORs with WARNs
- Fix calls to restore GT and PM interrupts
- Use intel_mark_busy instead of intel_ring_advance to disable PC8
v4: - Use the force_wake, Luke!
v5: - Remove the "IIR is not zero" WARNs
- Move the force_wake chunk to its own patch
- Only restore what's missing from RC6, not everything
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Because hsw_pm_irq_handler does exactly what gen6_rps_irq_handler does
and also processes the 2 additional VEBOX bits. So merge those
functions and wrap the VEBOX bits on a HAS_VEBOX check. This
check isn't really necessary since the bits are reserved on
SNB/IVB/VLV, but it's a good documentation on who uses them.
v2: - Change IS_HASWELL check to HAS_VEBOX
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
It seems we've been doing this ever since we started processing the
RPS events on a work queue, on commit "drm/i915: move gen6 rps
handling to workqueue", 4912d04193.
The problem is: when we add work to the queue, instead of just masking
the bits we queued and leaving all the others on their current state,
we mask the bits we queued and unmask all the others. This basically
means we'll be unmasking a bunch of interrupts we're not going to
process. And if you look at gen6_pm_rps_work, we unmask back only
GEN6_PM_RPS_EVENTS, which means the bits we unmasked when adding work
to the queue will remain unmasked after we process the queue.
Notice that even though we unmask those unrelated interrupts, we never
enable them on IER, so they don't fire our interrupt handler, they
just stay there on IIR waiting to be cleared when something else
triggers the interrupt handler.
So this patch does what seems to make more sense: mask only the bits
we add to the queue, without unmasking anything else, and so we'll
unmask them after we process the queue.
As a side effect we also have to remove that WARN, because it is not
only making sure we don't mask useful interrupts, it is also making
sure we do unmask useless interrupts! That piece of code should not be
responsible for knowing which bits should be unmasked, so just don't
assert anything, and trust that snb_disable_pm_irq should be doing the
right thing.
With i915.enable_pc8=1 I was getting ocasional "GEN6_PMIIR is not 0"
error messages due to the fact that we unmask those unrelated
interrupts but don't enable them.
Note: if bugs start bisecting to this patch, then it probably means
someone was relying on the fact that we unmask everything by accident,
then we should fix gen5_gt_irq_postinstall or whoever needs the
accidentally unmasked interrupts. Or maybe I was just wrong and we
need to revert this patch :)
Note: This started to be a more real issue with the addition of the
VEBOX support since now we do enable more than just the minimal set of
RPS interrupts in the IER register. Which means after the first rps
interrupt has happened we will never mask the VEBOX user interrupts
again and so will blow through cpu time needlessly when running video
workloads.
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
[danvet: Add note that this started to matter with VEBOX much more.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
On SNB/IVB/VLV we only call gen6_rps_irq_handler if one of the IIR
bits set is part of GEN6_PM_RPS_EVENTS, but at gen6_rps_irq_handler we
add all the enabled IIR bits to the work queue, not only the ones that
are part of GEN6_PM_RPS_EVENTS. But then gen6_pm_rps_work only
processes GEN6_PM_RPS_EVENTS, so it's useless to add anything that's
not GEN6_PM_RPS_EVENTS to the work queue.
As a bonus, gen6_rps_irq_handler looks more similar to
hsw_pm_irq_handler, so we may be able to merge them in the future.
v2: - Add a WARN in case we queued something we're not going to
process.
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net> (v1)
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
If the error interrupts are already disabled, don't disable and
reenable them. This is going to be needed when we're in PC8+, where
all the interrupts are disabled so we won't risk re-enabling
DE_ERR_INT_IVB.
v2: Use dev_priv->irq_mask (Chris)
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Just like irq_mask and gt_irq_mask, use it to track the status of
GEN6_PMIMR so we don't need to read it again every time we call
snb_update_pm_irq.
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
I did some brief tests and the "new_val = pmimr" condition usually
happens a few times after exiting games.
Note: This is also prep work to track the GEN6_PMIMR register state in
dev_priv->pm_imr. This happens in the next patch.
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
[danvet: Add note to explain why we want this, as per the discussion
between Chris and Paulo.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Just like we're doing with the other IMR changes.
One of the functional changes is that not every caller was doing the
POSTING_READ.
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Just like the functions that touch DEIMR and SDEIMR, but for GTIMR.
The new functions contain a POSTING_READ(GTIMR) which was not present
at the 2 callers inside i915_irq.c.
The implementation is based on ibx_display_interrupt_update.
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Although I could not reproduce this (different compiler version,
perhaps), reportedly we get:
drivers/gpu/drm/i915/i915_irq.c:1943:27: warning: ‘score’ may be used
uninitialized in this function [-Wuninitialized]
Drop the 'score' variable altogether as it's not really needed.
Reported-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The short lowercase names are bound to collide. The default warnings
don't even warn about shadowing.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
It's been there since i8xx_irq_handler() was added in
commit c2798b19ba
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date: Sun Apr 22 21:13:57 2012 +0100
drm/i915: i8xx interrupt handler
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
For HPD storm detection we now mask out individual interrupt source
bits. We have already seen a case where HPD interrupt enable bits
were assigned to the wrong pins. To track these conditions more
easily add some debugging messages.
v2: Spelling fixes as suggested by Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Egbert Eich <eich@suse.de>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Currently, the register access code is split between i915_drv.c and
intel_pm.c. It only bares a superficial resemblance to the reset of the
powermanagement code, so move it all into its own file. This is to ease
further patches to enforce serialised register access.
v2: Scan for random abuse of I915_WRITE_NOTRACE
v3: Take the opportunity to rename the GT functions as uncore. Uncore is
the term used by the hardware design (and bspec) for all functions
outside of the GPU (and CPU) cores in what is also known as the System
Agent.
v4: Rebase onto SNB rc6 fixes
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
[danvet: Wrestle patch into applying and inline
intel_uncore_early_sanitize (plus move the old comment to the new
function). Also keep the _santize postfix for intel_uncore_sanitize.]
[danvet: Squash in fixup spotted by Chris on irc: We need to call
intel_pm_init before intel_uncore_sanitize since the later will call
cancel_work on the delayed rps setup work the former initializes.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Make the uevent strings part of the user API for people who wish to
write their own listeners.
v2: Make a space in the string concatenation. (Chad)
Use the "UEVENT" suffix intead of "EVENT" (Chad)
Make kernel-doc parseable Docbook comments (Daniel)
v3: Undid reset change introduced in last submission (Daniel)
Fixed up comments to address removal changes.
Thanks to Daniel Vetter for a majority of the parity error comments.
CC: Chad Versace <chad.versace@linux.intel.com>
Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
It was very similar to ironlake_irq_postinstall, so IMHO merging both
functions results in a code that is easier to maintain.
With this change, all the irq handler vfuncs between ironlake and
ivybridge are now unified.
v2: Add "(" and ")" to make at least one vim user much happier (Chris)
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The IVB funtions are exactly the same as the ILK ones, with the
exception of the bit register. So add IVB/HSW support to
ironlake_enable_vblank and ironlake_disable_vblank, then kill the
ivybridge functions.
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
And then rename it to ironlake_irq_handler. Also move
ilk_gt_irq_handler up to avoid forward declarations.
In the previous patches I did small modifications to both
ironlake_irq_handler an ivybridge_irq_handler so they became very
similar functions. Now it should be very easy to verify that all we
need to add ILK/SNB support is to call ilk_gt_irq_handler, call
ilk_display_irq_handler and avoid reading pm_iir on gen 5.
v2: - Rebase due to changes on the previous patches
- Move pm_iir to a tighter scope (Chris)
- Change some Gen checks for readability
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
We have this POSTING_READ inside ironlake_irq_handler. I suppose we
also want it on IVB because we want to stop the IRQ handler as soon as
possible at this point.
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The ironlake_irq_handler and ivybridge_irq_handler functions do
basically the same thing, but they have different implementation
styles. With this patch we reorganize ironlake_irq_handler in a way
that makes it look very similar to ivybridge_irq_handler.
One of the advantages of this new function style is that we don't
write 0 to the IIR registers anymore.
v2: - Rebase due to changes on previous patches
- Move pm_iir to a tighter scope (Chris)
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The register doesn't exist on Gen 5.
v2: Simplify checks since pm_iir is always 0 on Gen 5 (Chris)
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Just like we did with ilk_display_irq_handler.
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
It's the code that deals with de_iir.
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
After Daniel's latest changes it's now equal to
ironlake_irq_preinstall.
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
To run hangcheck in near future.
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Again extract a common helper. For the postinstall hook things are a
bit more complicated since we have more cases on ilk-hsw/vlv here.
But since vlv was clearly broken by failing to initialize
dev_priv->gt_irq_mask correctly the shared code is clearly justified.
Also kill the PMIER setting in the async rps enable work. I should
have been save, but also clearly looked rather fragile. PMIER setup is
now all down in the irq pre/postinstall hooks.
With this we now have the usual interrupt register sequence for GT/PM
irq registers:
- IER is setup once with all the interrupts we ever need in the
postinstall hook and never touched again. Exceptions are SDEIER,
which is touched in the preinstall hook (when the irq handler isn't
enabled) and then only from the irq handler. And DEIER/VLV_IER with
is used in the irq handler but also written to once in the
postinstall hook. But since that write is essentially what enables
the interrupt and we should always have MSI interrupts we should be
save. In case we ever have non-MSI interrupts we'd be screwed.
- IIR is cleared in the postinstall hook before we enable/unmask the
respective interrupt sources. Hence we can't steal an interrupt
event an accidentally trigger the spurious interrupt logic in the
core kernel. Note that after some discussion with Ben Widawsky we
think that we actually should clear the IIR registers in the
preinstall hook. But doing that is a much larger patch series.
- IMR regs are (usually) all masked off. Those are the only regs
changed at runtime, which is all protected by dev_priv->irq_lock.
This unification also kills the cargo-culted read-modify-write PM
register setup for VECS. Interrupt setup is done without userspace
being able to interfere, so we better know what values we want to put
into those registers. RMW cycles otoh are really good at papering over
races, until stuff magically blows up and no one has a clue why.
v2: Touch the gen6+ PM interrupt registers only on gen6+.
v3: Improve the commit message to more clearly spell out why we want
to unify the code and what exactly changes.
Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: Paulo Zanoni <przanoni@gmail.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
[danvet: Add a comment to explain why the l3 parity interrupt is
special.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Since the addition of VECS we have a slightly different enable
sequence for PM interrupts on ivb/hsw vs snb and vlv. Usually that
will end up in hard to track down surprises.
Hence unifiy things and since we have copies of this code in 3 places
now, extract it into its own little helper.
Note that this changes the irq preinstall sequence a bit for snb and
vlv: We now also clear the PM registers in the preinstall hook, in
addition to the PM register clearing/setup already done when actually
enabling rps. So this doesn't fix a bug but simply unifies the code
across all platforms. After the postinstall hook is similarly unified
we can rip out the then redundant PM interrupt setup from the rps
code.
v3: Rebase on top of the retained double-GTIIR clearing. Also
resurrect the masking/disabling of the gen6+ PM interrupts as spotted
by Ben Widaswky.
v4: Move the DE interrupt reset code out of gen5_gt_irq_preinstall
back to ironlake_irq_preinstall where it really belongs. Spotted by
Paulo.
v3: Improve the commit message to more clearly spell out why we want
to unify the code and what exactly changes.
Cc: Paulo Zanoni <przanoni@gmail.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
[danvet: s/GT/PM/ to fix up a comment which Ben spotted while
reviewing.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Move error state generation and stringification to it's
own compilation unit. Sysfs also uses this so it can't be
under CONFIG_DEBUG_FS
This fixes a regression introduced in
commit ef86ddced7
Author: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Date: Thu Jun 6 17:38:54 2013 +0300
drm/i915: add error_state sysfs entry
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=66814
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The code to handle it is broken - there's simply no code to clear CS
parser errors on gen5+. And behold, for all the other rings we also
don't enable it!
Leave the handling code itself in place just to be consistent with the
existing mess though. And in case someone feels like fixing it all up.
This has been errornously enabled in
commit 12638c57f3
Author: Ben Widawsky <ben@bwidawsk.net>
Date: Tue May 28 19:22:31 2013 -0700
drm/i915: Enable vebox interrupts
Cc: Damien Lespiau <damien.lespiau@intel.com>
Cc: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Now that the rps interrupt locking isn't clearly separated (at elast
conceptually) from all the other interrupt locking having a different
lock stopped making sense: It protects much more than just the rps
workqueue it started out with. But with the addition of VECS the
separation started to blurr and resulted in some more complex locking
for the ring interrupt refcount.
With this we can (again) unifiy the ringbuffer irq refcounts without
causing a massive confusion, but that's for the next patch.
v2: Explain better why the rps.lock once made sense and why no longer,
requested by Ben.
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
And kill the comment about it. Queueing work is a barrier type event,
no amount of locking will help in ordering things (as long as we queue
the work after having updated all relevant data structures). Also, the
queue_work works itself as a sufficient memory barrier.
Again on the surface this is just a tiny micro-optimization to reduce
the hold-time of dev_priv->irq_lock. But the better reason is that it
reduces superficial locking and so makes it clearer what we actually
need for correctness.
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The if (pm_iir & ~GEN6_PM_RPS_EVENTS) check was redunandant. Otoh
adding a check for rps events allows us to avoid the spinlock grabbing
for VECS interrupts.
v2: Drop misplaced hunk which now moved to the right patch.
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Since we only have one interrupt handler and interrupt handlers are
non-reentrant.
To drive the point really home give them all an _irq_handler suffix.
This is a tiny micro-optimization but even more important it makes it
clearer what locking we actually need. And in case someone screws this
up: lockdep will catch hardirq vs. other context deadlocks.
v2: Fix up compile fail.
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
It's racy: There's no guarantee that we won't walk this code (due to a
pch fifo underrun interrupt) while someone is changing the pointers
around.
The only reason we do this is to use the righ crtc for the pch fifo
underrun accounting. But we never expose this to userspace, so
essentially no one really cares if we use the "wrong" crtc.
So let's just rip it out.
With this patch fifo underrun code will always use crtc A for tracking
underruns on the (only) pch transcoder on LPT.
v2: Add a big comment explaining what's going on. Requested by Paulo.
v3: Fixup spelling in comment as spotted by Paulo.
Cc: Paulo Zanoni <przanoni@gmail.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
