Pull i915 drm fixes from Jani Nikula:
"Here's a batch of i915 fixes all around. It may be slightly bigger
than one would hope for at this stage, but they've all been through
testing in our -next before being picked up for v4.4. Also, I missed
Dave's fixes pull earlier today just because I wanted an extra testing
round on this. So I'm fairly confident.
Wishing you all the things it is customary to wish this time of the
year"
* tag 'drm-intel-fixes-2015-12-23' of git://anongit.freedesktop.org/drm-intel:
drm/i915: Correct max delay for HDMI hotplug live status checking
drm/i915: mdelay(10) considered harmful
drm/i915: Kill intel_crtc->cursor_bo
drm/i915: Workaround CHV pipe C cursor fail
drm/i915: Only spin whilst waiting on the current request
drm/i915: Limit the busy wait on requests to 5us not 10ms!
drm/i915: Break busywaiting for requests on pending signals
drm/i915: Disable primary plane if we fail to reconstruct BIOS fb (v2)
drm/i915: Set the map-and-fenceable flag for preallocated objects
drm/i915: Drop the broken cursor base==0 special casing
The total delay of HDMI hotplug detecting with 30ms have already
been split into a resolution of 3 retries of 10ms each, for the worst
cases. But it still suffered from only waiting 10ms at most in
intel_hdmi_detect(). This patch corrects it by reading hotplug status
with 4 times at most for 30ms delay.
v2:
- straight up to loop execution for more clear in code readability
- mdelay will replace with msleep by Daniel's new patch
drm/i915: mdelay(10) considered harmful
- suggest to re-evaluate try times for being compatible to old HDMI monitor
Reviewed-by: Cooper Chiou <cooper.chiou@intel.com>
Tested-by: Gary Wang <gary.c.wang@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Gavin Hindman <gavin.hindman@intel.com>
Cc: Sonika Jindal <sonika.jindal@intel.com>
Cc: Shashank Sharma <shashank.sharma@intel.com>
Signed-off-by: Gary Wang <gary.c.wang@intel.com>
[danvet: fixup conflict with s/mdelay/msleep/ patch.]
Cc: drm-intel-fixes@lists.freedesktop.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
(cherry picked from commit 61fb3980dd)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
I missed this myself when reviewing
commit 237ed86c69
Author: Sonika Jindal <sonika.jindal@intel.com>
Date: Tue Sep 15 09:44:20 2015 +0530
drm/i915: Check live status before reading edid
Long sleeps like this really shouldn't waste cpu cycles spinning.
Cc: Sonika Jindal <sonika.jindal@intel.com>
Cc: "Wang, Gary C" <gary.c.wang@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1449859455-32609-1-git-send-email-daniel.vetter@ffwll.ch
Reviewed-by: Sonika Jindal <sonika.jindal@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
(cherry picked from commit 71a199bacb)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
The vma may have been rebound between the last time the cursor was
enabled and now, so skipping the cursor gtt offset deduction is not
safe unless we would also reset cursor_bo to NULL when disabling the
cursor. Just thow cursor_bo to the bin instead since it's lost all
other uses thanks to universal plane support.
Chris pointed out that cursor updates are currently too slow
via universal planes that micro optimizations like these wouldn't
even help.
v2: Add a note about futility of micro optimizations (Chris)
Cc: drm-intel-fixes@lists.freedesktop.org
References: http://lists.freedesktop.org/archives/intel-gfx/2015-December/082976.html
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450107302-17171-1-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
(cherry picked from commit 1264859d64)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Turns out CHV pipe C was glued on somewhat poorly, and there's something
wrong with the cursor. If the cursor straddles the left screen edge,
and is then moved away from the edge or disabled, the pipe will often
underrun. If enough underruns are triggered quickly enough the pipe
will fall over and die (it just scans out a solid color and reports
a constant underrun). We need to turn the disp2d power well off and
on again to recover the pipe.
None of that is very nice for the user, so let's just refuse to place
the cursor in the compromised position. The ddx appears to fall back
to swcursor when the ioctl returns an error, so theoretically there's
no loss of functionality for the user (discounting swcursor bugs).
I suppose most cursors images actually have the hotspot not exactly
at 0,0 so under typical conditions the fallback will in fact kick in
as soon as the cursor touches the left edge of the screen.
Any atomic compositor should anyway be prepared to fall back to
GPU composition when things don't work out, so there should be no
problem with those.
Other things that I tried to solve this include flipping all
display related clock gating knobs I could find, increasing the
minimum gtt alignment all the way up to 512k. I also tried to see
if there are more specific screen coordinates that hit the bug, but
the findings were somewhat inconclusive. Sometimes the failures
happen almost across the whole left edge, sometimes more at the very
top and around the bottom half. I wasn't able to find any real pattern
to these variations, so it seems our only choice is to just refuse
to straddle the left screen edge at all.
Cc: stable@vger.kernel.org
Cc: Jason Plum <max@warheads.net>
Testcase: igt/kms_chv_cursor_fail
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92826
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450459479-16286-1-git-send-email-ville.syrjala@linux.intel.com
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
(cherry picked from commit b29ec92c4f)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Limit busywaiting only to the request currently being processed by the
GPU. If the request is not currently being processed by the GPU, there
is a very low likelihood of it being completed within the 2 microsecond
spin timeout and so we will just be wasting CPU cycles.
v2: Check for logical inversion when rebasing - we were incorrectly
checking for this request being active, and instead busywaiting for
when the GPU was not yet processing the request of interest.
v3: Try another colour for the seqno names.
v4: Another colour for the function names.
v5: Remove the forced coherency when checking for the active request. On
reflection and plenty of recent experimentation, the issue is not a
cache coherency problem - but an irq/seqno ordering problem (timing issue).
Here, we do not need the w/a to force ordering of the read with an
interrupt.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: "Rogozhkin, Dmitry V" <dmitry.v.rogozhkin@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Eero Tamminen <eero.t.tamminen@intel.com>
Cc: "Rantala, Valtteri" <valtteri.rantala@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1449833608-22125-4-git-send-email-chris@chris-wilson.co.uk
(cherry picked from commit 821485dc2a)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
When waiting for high frequency requests, the finite amount of time
required to set up the irq and wait upon it limits the response rate. By
busywaiting on the request completion for a short while we can service
the high frequency waits as quick as possible. However, if it is a slow
request, we want to sleep as quickly as possible. The tradeoff between
waiting and sleeping is roughly the time it takes to sleep on a request,
on the order of a microsecond. Based on measurements of synchronous
workloads from across big core and little atom, I have set the limit for
busywaiting as 10 microseconds. In most of the synchronous cases, we can
reduce the limit down to as little as 2 miscroseconds, but that leaves
quite a few test cases regressing by factors of 3 and more.
The code currently uses the jiffie clock, but that is far too coarse (on
the order of 10 milliseconds) and results in poor interactivity as the
CPU ends up being hogged by slow requests. To get microsecond resolution
we need to use a high resolution timer. The cheapest of which is polling
local_clock(), but that is only valid on the same CPU. If we switch CPUs
because the task was preempted, we can also use that as an indicator that
the system is too busy to waste cycles on spinning and we should sleep
instead.
__i915_spin_request was introduced in
commit 2def4ad99b [v4.2]
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date: Tue Apr 7 16:20:41 2015 +0100
drm/i915: Optimistically spin for the request completion
v2: Drop full u64 for unsigned long - the timer is 32bit wraparound safe,
so we can use native register sizes on smaller architectures. Mention
the approximate microseconds units for elapsed time and add some extra
comments describing the reason for busywaiting.
v3: Raise the limit to 10us
v4: Now 5us.
Reported-by: Jens Axboe <axboe@kernel.dk>
Link: https://lkml.org/lkml/2015/11/12/621
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: "Rogozhkin, Dmitry V" <dmitry.v.rogozhkin@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Eero Tamminen <eero.t.tamminen@intel.com>
Cc: "Rantala, Valtteri" <valtteri.rantala@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1449833608-22125-3-git-send-email-chris@chris-wilson.co.uk
(cherry picked from commit ca5b721e23)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
The busywait in __i915_spin_request() does not respect pending signals
and so may consume the entire timeslice for the task instead of
returning to userspace to handle the signal.
In the worst case this could cause a delay in signal processing of 20ms,
which would be a noticeable jitter in cursor tracking. If a higher
resolution signal was being used, for example to provide fairness of a
server timeslices between clients, we could expect to detect some
unfairness between clients (i.e. some windows not updating as fast as
others). This issue was noticed when inspecting a report of poor
interactivity resulting from excessively high __i915_spin_request usage.
Fixes regression from
commit 2def4ad99b [v4.2]
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date: Tue Apr 7 16:20:41 2015 +0100
drm/i915: Optimistically spin for the request completion
v2: Try to assess the impact of the bug
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc; "Rogozhkin, Dmitry V" <dmitry.v.rogozhkin@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Eero Tamminen <eero.t.tamminen@intel.com>
Cc: "Rantala, Valtteri" <valtteri.rantala@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1449833608-22125-2-git-send-email-chris@chris-wilson.co.uk
(cherry picked from commit 91b0c352ac)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
If we fail to reconstruct the BIOS fb (e.g., because the FB is too
large), we'll be left with plane state that indicates the primary plane
is visible yet has a NULL fb. This mismatch causes problems later on
(e.g., for the watermark code). Since we've failed to reconstruct the
BIOS FB, the best solution is to just disable the primary plane and
pretend the BIOS never had it enabled.
v2: Add intel_pre_disable_primary() call (Maarten)
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Ville Syrjälä <ville.syrjala@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: drm-intel-fixes@lists.freedesktop.org
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1449171462-30763-2-git-send-email-matthew.d.roper@intel.com
(cherry picked from commit 200757f5d7)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
As we mark the preallocated objects as bound, we should also flag them
correctly as being map-and-fenceable (if appropriate!) so that later
users do not get confused and try and rebind the pinned vma in order to
get a map-and-fenceable binding.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: "Goel, Akash" <akash.goel@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: drm-intel-fixes@lists.freedesktop.org
Link: http://patchwork.freedesktop.org/patch/msgid/1448029000-10616-1-git-send-email-chris@chris-wilson.co.uk
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
(cherry picked from commit d0710abbcd)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
The cursor code tries to treat base==0 to mean disabled. That fails
when the cursor bo gets bound at ggtt offset 0, and the user is left
looking at an invisible cursor.
We lose the disabled->disabled optimization, but that seems like
something better handled at a slightly higher level.
Cc: drm-intel-fixes@lists.freedesktop.org
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1450091808-32607-3-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
(cherry picked from commit 663f3122d0)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Since atomic check is called also for disabled crtcs it should skip
mode checking as it can be uninitialized. The patch fixes it.
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
This is an oversight that made use of the trip-point-based fan managenent on
cards that never expose those. This led the fan to stay at fan_min.
Fortunately, the emergency code would kick when the temperature would reach
90°C.
Reported-by: Tom Englund <tomenglund26@gmail.com>
Tested-by: Tom Englund <tomenglund26@gmail.com>
Signed-off-by: Martin Peres <martin.peres@free.fr>
Tested-by: Daemon32 <lnf.purple@gmail.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92126
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Cc: stable@vger.kernel.org
This fixes a random corruption under memory pressure. We need to fence
the BO for the user fence as well, otherwise it might be swapped out
and the GPU could write the fence value to an undesired location.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
The way the mode probing works is this:
1. All modes currently on the mode list are marked as UNVERIFIED
2. New modes are on the probed_modes list (they start with
status OK)
3. Modes are moved from the probed_modes list to the actual
mode list. If a mode already on the mode list is deemed
to match one of the probed modes, the duplicate is dropped
and the mode status updated to OK. After this the
probed_modes list will be empty.
4. All modes on the mode list are verified to not violate any
constraints. Any that do are marked as such.
5. Any mode left with a non-OK status is pruned from the list,
with an appropriate debug message.
What all this means is that any mode on the original list that
didn't have a duplicate on the probed_modes list, should be left
with status UNVERFIED (or previously could have been left with
some other status, but never OK).
I broke that in
commit 05acaec334 ("drm: Reorganize probed mode validation")
by always assigning something to the mode->status during the validation
step. So any mode from the old list that still passed the validation
would be left on the list with status OK in the end.
Fix this by not doing the basic mode validation unless the mode
already has status OK (meaning it came from the probed_modes list,
or at least a duplicate of it was on that list). This way we will
correctly prune away any mode from the old mode list that didn't
appear on the probed_modes list.
Cc: stable@vger.kernel.org
Cc: Adam Jackson <ajax@redhat.com>
Fixes: 05acaec334 ("drm: Reorganize probed mode validation")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1449177255-9515-2-git-send-email-ville.syrjala@linux.intel.com
Testcase: igt/kms_force_connector_basic/prune-stale-modes
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=93332
[danvet: Also applying to drm-misc to avoid too much conflict hell -
there's a big pile of patches from Ville on top of this one.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Here are some i915 fixes for v4.4, sorry for being late this week.
* tag 'drm-intel-fixes-2015-12-11' of git://anongit.freedesktop.org/drm-intel:
drm/i915: Do a better job at disabling primary plane in the noatomic case.
drm/i915/skl: Double RC6 WRL always on
drm/i915/skl: Disable coarse power gating up until F0
drm/i915: Remove incorrect warning in context cleanup
omap_fbdev always creates a framebuffer with ARGB8888 pixel format. On
OMAP3 we have VIDEO1 overlay that does not support ARGB8888, and on
OMAP2 none of the overlays support ARGB888.
This patch changes the omap_fbdev's fb to XRGB8888, which is supported
by all platforms.
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Tested-by: H. Nikolaus Schaller <hns@goldelico.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
some big endian fixes and one regression fix.
* 'drm-fixes-4.4' of git://people.freedesktop.org/~agd5f/linux:
radeon: Fix VCE IB test on Big-Endian systems
radeon: Fix VCE ring test for Big-Endian systems
radeon/cik: Fix GFX IB test on Big-Endian
drm/amdgpu: fix the lost duplicates checking
When disable_noatomic is called plane_mask is not correct yet, and
plane_state->visible = true is left as true after disabling the primary
plane.
Other planes are already disabled as part of crtc sanitization, only the
primary is left active. But the plane_mask is not updated here. It gets
updated during fb takeover in modeset_gem_init, or set to the new value
on resume.
This means that to disable the primary plane 1 << drm_plane_index(primary)
needs to be used.
Afterwards because the crtc is no longer active it's forbidden to keep
plane_state->visible set, or a WARN_ON in
intel_plane_atomic_calc_changes triggers. There are other code points
that rely on accurate plane_state->visible too, so make sure the bool is
cleared.
The other planes are already disabled in intel_sanitize_crtc, so they
don't have to be handled here.
Cc: stable@vger.kernel.org #v4.3, v4.2?
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92655
Tested-by: Tomas Mezzadra <tmezzadra@gmail.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/5652DB88.9070208@linux.intel.com
(cherry picked from commit 54a4196188)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
This patch makes the VCE IB test pass on Big-Endian systems. It converts
to little-endian the contents of the VCE message.
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This patch fixes the VCE ring test when running on Big-Endian machines.
Every write to the ring needs to be translated to little-endian.
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This patch makes the IB test on the GFX ring pass for CI-based cards
installed in Big-Endian machines.
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Pull request of 2015-12-08
A couple of fixes for vmwgfx. A WARN() fix by Dan Carpenter,
a TTM read/write lock imbalance causing occasional hangs with Wayland and
an implementation of cursor_set2 to fix incorrectly offset Wayland cursors.
* tag 'vmwgfx-fixes-4.4-151208' of git://people.freedesktop.org/~thomash/linux:
drm/vmwgfx: Implement the cursor_set2 callback v2
drm/vmwgfx: fix a warning message
drm/ttm: Fixed a read/write lock imbalance
Just the one commit I mentioned earlier, making the PGOB workaround the
default.
* 'linux-4.4' of https://github.com/skeggsb/linux:
drm/nouveau/pmu: remove whitelist for PGOB-exit WAR, enable by default
NVIDIA have indicated that the workaround is required on all GK10[467]
boards that have the PGOB fuse set.
I've left the commandline option in place for now, as paranoia.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
There is conflicting info between E0 and F0 steppings
for this workarounds. Trust more authoritative source and
be conservative and extend also for F0.
This prevents numerous (>50) gpu hangs with SKL GT4e
during piglit run.
References: HSD: gen9lp/2134184
Cc: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1449505785-20812-1-git-send-email-mika.kuoppala@intel.com
(cherry picked from commit 6686ece19f)
Cc: stable@vger.kernel.org # v4.3+
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Fixes native drm clients like Fedora 23 Wayland which now appears to
be able to use cursor hotspots without strange cursor offsets.
Also fixes a couple of ignored error paths.
Since the core drm cursor hotspot is incompatible with the legacy vmwgfx
hotspot (the core drm hotspot is reset when the drm_mode_cursor ioctl
is used), we need to keep track of both and add them when the device
hotspot is set. We assume that either is always zero.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>
Commit e9f24d5fb7
Author: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Date: Mon Oct 5 13:26:36 2015 +0100
drm/i915: Clean up associated VMAs on context destruction
Added a warning based on an incorrect assumption that all VMAs
in a VM will be on the inactive list at the point last reference
to a context and VM is dropped.
This is not true because i915_gem_object_retire__read will not
put VMA on the inactive list until all activities on the object
in question (in all VMs) have been retired.
As a consequence, whether or not a context/VM will be destroyed
with its VMAs still on the active list, can depend on completely
unrelated activities using the same object from a different
context or engine.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92638
Testcase: igt/gem_request_retire/retire-vma-not-inactive
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michel Thierry <michel.thierry@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448025816-25584-1-git-send-email-tvrtko.ursulin@linux.intel.com
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
(cherry picked from commit 408952d43b)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
A few more last minute fixes for 4.4 on top of my pull request from
earlier this week. The big change here is a vblank regression fix due to
commit 4dfd6486 "drm: Use vblank timestamps to guesstimate how many vblanks
were missed". Beyond that, a hotplug fix and a few VM fixes.
* 'drm-fixes-4.4' of git://people.freedesktop.org/~agd5f/linux:
drm/amdgpu: Fixup hw vblank counter/ts for new drm_update_vblank_count() (v3)
drm/radeon: Fixup hw vblank counter/ts for new drm_update_vblank_count() (v2)
drm/radeon: Retry DDC probing on DVI on failure if we got an HPD interrupt
drm/amdgpu: add spin lock to protect freed list in vm (v2)
drm/amdgpu: partially revert "drm/amdgpu: fix VM_CONTEXT*_PAGE_TABLE_END_ADDR" v2
drm/amdgpu: take a BO reference for the user fence
drm/amdgpu: take a BO reference in the display code
drm/amdgpu: set snooped flags only on system addresses v2
drm/amdgpu: fix race condition in amd_sched_entity_push_job
drm/amdgpu: add err check for pin userptr
add blacklist for thinkpad T40p
drm/amdgpu: fix VM page table reference counting
drm/amdgpu: fix userptr flags check
commit 4dfd6486 "drm: Use vblank timestamps to guesstimate how many
vblanks were missed" introduced in Linux 4.4-rc1 makes the drm core
more fragile to drivers which don't update hw vblank counters and
vblank timestamps in sync with firing of the vblank irq and
essentially at leading edge of vblank.
This exposed a problem with radeon-kms/amdgpu-kms which do not
satisfy above requirements:
The vblank irq fires a few scanlines before start of vblank, but
programmed pageflips complete at start of vblank and
vblank timestamps update at start of vblank, whereas the
hw vblank counter increments only later, at start of vsync.
This leads to problems like off by one errors for vblank counter
updates, vblank counters apparently going backwards or vblank
timestamps apparently having time going backwards. The net result
is stuttering of graphics in games, or little hangs, as well as
total failure of timing sensitive applications.
See bug #93147 for an example of the regression on Linux 4.4-rc:
https://bugs.freedesktop.org/show_bug.cgi?id=93147
This patch tries to align all above events better from the
viewpoint of the drm core / of external callers to fix the problem:
1. The apparent start of vblank is shifted a few scanlines earlier,
so the vblank irq now always happens after start of this extended
vblank interval and thereby drm_update_vblank_count() always samples
the updated vblank count and timestamp of the new vblank interval.
To achieve this, the reporting of scanout positions by
radeon_get_crtc_scanoutpos() now operates as if the vblank starts
radeon_crtc->lb_vblank_lead_lines before the real start of the hw
vblank interval. This means that the vblank timestamps which are based
on these scanout positions will now update at this earlier start of
vblank.
2. The driver->get_vblank_counter() function will bump the returned
vblank count as read from the hw by +1 if the query happens after
the shifted earlier start of the vblank, but before the real hw increment
at start of vsync, so the counter appears to increment at start of vblank
in sync with the timestamp update.
3. Calls from vblank irq-context and regular non-irq calls are now
treated identical, always simulating the shifted vblank start, to
avoid inconsistent results for queries happening from vblank irq vs.
happening from drm_vblank_enable() or vblank_disable_fn().
4. The radeon_flip_work_func will delay mmio programming a pageflip until
the start of the real vblank iff it happens to execute inside the shifted
earlier start of the vblank, so pageflips now also appear to execute at
start of the shifted vblank, in sync with vblank counter and timestamp
updates. This to avoid some races between updates of vblank count and
timestamps that are used for swap scheduling and pageflip execution which
could cause pageflips to execute before the scheduled target vblank.
The lb_vblank_lead_lines "fudge" value is calculated as the size of
the display controllers line buffer in scanlines for the given video
mode: Vblank irq's are triggered by the line buffer logic when the line
buffer refill for a video frame ends, ie. when the line buffer source read
position enters the hw vblank. This means that a vblank irq could fire at
most as many scanlines before the current reported scanout position of the
crtc timing generator as the number of scanlines the line buffer can
maximally hold for a given video mode.
This patch has been successfully tested on a RV730 card with DCE-3 display
engine and on a evergreen card with DCE-4 display engine, in single-display
and dual-display configuration, with different video modes.
A similar patch is needed for amdgpu-kms to fix the same problem.
Limitations:
- Maybe replace the udelay() in the flip_work_func() by a suitable
usleep_range() for a bit better efficiency? Will try that.
- Line buffer sizes in pixels are hard-coded on < DCE-4 to a value
i just guessed to be high enough to work ok, lacking info on the true
sizes atm.
Probably fixes: fdo#93147
Port of Mario's radeon fix to amdgpu.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(v1) Reviewed-by: Mario Kleiner <mario.kleiner.de@gmail.com>
(v2) Refine amdgpu_flip_work_func() for better efficiency.
In amdgpu_flip_work_func, replace the busy waiting udelay(5)
with event lock held by a more performance and energy efficient
usleep_range() until at least predicted true start of hw vblank,
with some slack for scheduler happiness. Release the event lock
during waits to not delay other outputs in doing their stuff, as
the waiting can last up to 200 usecs in some cases.
Also small fix to code comment and formatting in that function.
(v2) Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
(v3) Fix crash in crtc disabled case
commit 4dfd6486 "drm: Use vblank timestamps to guesstimate how many
vblanks were missed" introduced in Linux 4.4-rc1 makes the drm core
more fragile to drivers which don't update hw vblank counters and
vblank timestamps in sync with firing of the vblank irq and
essentially at leading edge of vblank.
This exposed a problem with radeon-kms/amdgpu-kms which do not
satisfy above requirements:
The vblank irq fires a few scanlines before start of vblank, but
programmed pageflips complete at start of vblank and
vblank timestamps update at start of vblank, whereas the
hw vblank counter increments only later, at start of vsync.
This leads to problems like off by one errors for vblank counter
updates, vblank counters apparently going backwards or vblank
timestamps apparently having time going backwards. The net result
is stuttering of graphics in games, or little hangs, as well as
total failure of timing sensitive applications.
See bug #93147 for an example of the regression on Linux 4.4-rc:
https://bugs.freedesktop.org/show_bug.cgi?id=93147
This patch tries to align all above events better from the
viewpoint of the drm core / of external callers to fix the problem:
1. The apparent start of vblank is shifted a few scanlines earlier,
so the vblank irq now always happens after start of this extended
vblank interval and thereby drm_update_vblank_count() always samples
the updated vblank count and timestamp of the new vblank interval.
To achieve this, the reporting of scanout positions by
radeon_get_crtc_scanoutpos() now operates as if the vblank starts
radeon_crtc->lb_vblank_lead_lines before the real start of the hw
vblank interval. This means that the vblank timestamps which are based
on these scanout positions will now update at this earlier start of
vblank.
2. The driver->get_vblank_counter() function will bump the returned
vblank count as read from the hw by +1 if the query happens after
the shifted earlier start of the vblank, but before the real hw increment
at start of vsync, so the counter appears to increment at start of vblank
in sync with the timestamp update.
3. Calls from vblank irq-context and regular non-irq calls are now
treated identical, always simulating the shifted vblank start, to
avoid inconsistent results for queries happening from vblank irq vs.
happening from drm_vblank_enable() or vblank_disable_fn().
4. The radeon_flip_work_func will delay mmio programming a pageflip until
the start of the real vblank iff it happens to execute inside the shifted
earlier start of the vblank, so pageflips now also appear to execute at
start of the shifted vblank, in sync with vblank counter and timestamp
updates. This to avoid some races between updates of vblank count and
timestamps that are used for swap scheduling and pageflip execution which
could cause pageflips to execute before the scheduled target vblank.
The lb_vblank_lead_lines "fudge" value is calculated as the size of
the display controllers line buffer in scanlines for the given video
mode: Vblank irq's are triggered by the line buffer logic when the line
buffer refill for a video frame ends, ie. when the line buffer source read
position enters the hw vblank. This means that a vblank irq could fire at
most as many scanlines before the current reported scanout position of the
crtc timing generator as the number of scanlines the line buffer can
maximally hold for a given video mode.
This patch has been successfully tested on a RV730 card with DCE-3 display
engine and on a evergreen card with DCE-4 display engine, in single-display
and dual-display configuration, with different video modes.
A similar patch is needed for amdgpu-kms to fix the same problem.
Limitations:
- Line buffer sizes in pixels are hard-coded on < DCE-4 to a value
i just guessed to be high enough to work ok, lacking info on the true
sizes atm.
Fixes: fdo#93147
Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Michel Dänzer <michel.daenzer@amd.com>
Cc: Harry Wentland <Harry.Wentland@amd.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
(v1) Tested-by: Dave Witbrodt <dawitbro@sbcglobal.net>
(v2) Refine radeon_flip_work_func() for better efficiency:
In radeon_flip_work_func, replace the busy waiting udelay(5)
with event lock held by a more performance and energy efficient
usleep_range() until at least predicted true start of hw vblank,
with some slack for scheduler happiness. Release the event lock
during waits to not delay other outputs in doing their stuff, as
the waiting can last up to 200 usecs in some cases.
Retested on DCE-3 and DCE-4 to verify it still works nicely.
(v2) Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
HPD signals on DVI ports can be fired off before the pins required for
DDC probing actually make contact, due to the pins for HPD making
contact first. This results in a HPD signal being asserted but DDC
probing failing, resulting in hotplugging occasionally failing.
This is somewhat rare on most cards (depending on what angle you plug
the DVI connector in), but on some cards it happens constantly. The
Radeon R5 on the machine used for testing this patch for instance, runs
into this issue just about every time I try to hotplug a DVI monitor and
as a result hotplugging almost never works.
Rescheduling the hotplug work for a second when we run into an HPD
signal with a failing DDC probe usually gives enough time for the rest
of the connector's pins to make contact, and fixes this issue.
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Lyude <cpaul@redhat.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
there is a protection fault about freed list when OCL test.
add a spin lock to protect it.
v2: drop changes in vm_fini
Signed-off-by: JimQu <jim.qu@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
The gtt_end is already inclusive, we don't need to subtract one here.
v2 (chk): keep the fix for the VM code, cause here it really applies.
Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Anatoli Antonovitch <anatoli.antonovitch@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
No need for a GEM reference here.
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
No need for the GEM reference here.
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Not necessary for VRAM.
v2: no need to check if ttm is NULL.
Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Apparently pre-nv50 pageflip events happen before the actual vblank
period. Therefore that functionality got semi-disabled in
commit af4870e406
Author: Mario Kleiner <mario.kleiner.de@gmail.com>
Date: Tue May 13 00:42:08 2014 +0200
drm/nouveau/kms/nv04-nv40: fix pageflip events via special case.
Unfortunately that hack got uprooted in
commit cc1ef118fc
Author: Thierry Reding <treding@nvidia.com>
Date: Wed Aug 12 17:00:31 2015 +0200
drm/irq: Make pipe unsigned and name consistent
Triggering a warning when trying to sample the vblank timestamp for a
non-existing pipe. There's a few ways to fix this:
- Open-code the old behaviour, which just enshrines this slight
breakage of the userspace ABI.
- Revert Mario's commit and again inflict broken timestamps, again not
pretty.
- Fix this for real by delaying the pageflip TS until the next vblank
interrupt, thereby making it accurate.
This patch implements the third option. Since having a page flip
interrupt that happens when the pageflip gets armed and not when it
completes in the next vblank seems to be fairly common (older i915 hw
works very similarly) create a new helper to arm vblank events for
such drivers.
v2 (Mario Kleiner):
- Fix function prototypes in drmP.h
- Add missing vblank_put() for pageflip completion without
pageflip event.
- Initialize sequence number for queued pageflip event to avoid
trouble in drm_handle_vblank_events().
- Remove dead code and spelling fix.
v3 (Mario Kleiner):
- Add a signed-off-by and cc stable tag per Ilja's advice.
v4 (Thierry Reding):
- Fix kerneldoc typo, discovered by Michel Dänzer
- Rearrange tags and changelog
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=106431
Cc: Thierry Reding <treding@nvidia.com>
Cc: Mario Kleiner <mario.kleiner.de@gmail.com>
Acked-by: Ben Skeggs <bskeggs@redhat.com>
Cc: Ilia Mirkin <imirkin@alum.mit.edu>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Reviewed-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Cc: stable@vger.kernel.org # v4.3
Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
A client calling drmSetMaster() using a file descriptor that was opened
when another client was master would inherit the latter client's master
object and all its authenticated clients.
This is unwanted behaviour, and when this happens, instead allocate a
brand new master object for the client calling drmSetMaster().
Fixes a BUG() throw in vmw_master_set().
Cc: <stable@vger.kernel.org>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
- Use drm_crtc_send_vblank_event to fix per crtc vblank handling
- Move the crtc device of_node assignment out of the ipuv3-crtc driver into
ipu-common code, where the devices are created.
- Fix parallel display support with simple-panels
- Remove some unused fields and superfluous checks
- Switch to universal planes and add error handling for primary plane creation
- Fix module autoload for TV encoder driver
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=iEJU
-----END PGP SIGNATURE-----
Merge tag 'imx-drm-fixes-2015-12-01' of git://git.pengutronix.de/git/pza/linux into drm-fixes
imx-drm crtc, plane, parallel panel, and TV encoder fixes
- Use drm_crtc_send_vblank_event to fix per crtc vblank handling
- Move the crtc device of_node assignment out of the ipuv3-crtc driver into
ipu-common code, where the devices are created.
- Fix parallel display support with simple-panels
- Remove some unused fields and superfluous checks
- Switch to universal planes and add error handling for primary plane creation
- Fix module autoload for TV encoder driver
* tag 'imx-drm-fixes-2015-12-01' of git://git.pengutronix.de/git/pza/linux:
drm: imx: imx-tve: Fix module autoload for OF platform driver
drm: imx: convert to drm_crtc_send_vblank_event()
GPU-DRM-IMX: Delete an unnecessary check before drm_fbdev_cma_restore_mode()
drm/imx: Remove of_node assignment from ipuv3-crtc driver probe
gpu: ipu-v3: Assign of_node of child platform devices to corresponding ports
gpu: ipu-v3: Remove reg_offset field
gpu: ipu-v3: drop unused dmfc field from client platform data
drm/imx: parallel-display: allow to determine bus format from the connected panel
drm/imx: ipuv3-crtc: Return error if ipu_plane_init() fails for primary plane
drm/imx: switch to universal planes
Another batch of drm/i915 fixes for v4.4, on top of the ones from
earlier this week. One timeout handling regression fix from Chris, and
backport of five patches from our -next to fix a power management
related HDMI hotplug regression.
* tag 'drm-intel-fixes-2015-12-03' of git://anongit.freedesktop.org/drm-intel:
drm/i915: take a power domain reference while checking the HDMI live status
drm/i915: add MISSING_CASE to a few port/aux power domain helpers
drm/i915/ddi: fix intel_display_port_aux_power_domain() after HDMI detect
drm/i915: Introduce a gmbus power domain
drm/i915: Clean up AUX power domain handling
drm/i915: Check the timeout passed to i915_wait_request
As soon as we leave the spinlock after the job has been added to the job
queue, we can no longer rely on the job's data to be available.
I have seen a null-pointer dereference due to sched == NULL in
amd_sched_wakeup via amd_sched_entity_push_job and
amd_sched_ib_submit_kernel_helper. Since the latter initializes
sched_job->sched with the address of the ring scheduler, which is
guaranteed to be non-NULL, this race appears to be a likely culprit.
Signed-off-by: Nicolai Hähnle <nicolai.haehnle@amd.com>
Bugzilla: https://bugs.freedesktop.org/attachment.cgi?bugid=93079
Reviewed-by: Christian König <christian.koenig@amd.com>
Missing error check if the operation failed.
Signed-off-by: Chunming Zhou <David1.Zhou@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
There are platforms that don't need the full GMBUS power domain (BXT)
while others do (PCH, VLV/CHV). For optimizing this we would need to add
a new power domain, but it's not clear how much we would benefit given
the short time we hold the reference. So for now let's keep things
simple.
This fixes a regression introduced in
commit 237ed86c69
Author: Sonika Jindal <sonika.jindal@intel.com>
Date: Tue Sep 15 09:44:20 2015 +0530
drm/i915: Check live status before reading edid
v2:
- fix commit message, PCH won't take any redundant power resource after
this change (Ville)
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
[fix commit message in v2 (Imre)]
[Cherry-picked from drm-intel-next-queued 29bb94bb (Imre)]
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448643329-18675-6-git-send-email-imre.deak@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
MISSING_CASE() would have been useful to track down a recent problem in
intel_display_port_aux_power_domain(), so add it there and a few related
helpers. This was also suggested by Ville in his review of the latest
DMC/DC changes, we forgot to address that.
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
[Cherry-picked from drm-intel-next-queued b9fec167 (Imre)]
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448643329-18675-5-git-send-email-imre.deak@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Due to the current sharing of the DDI encoder between DP and HDMI
connectors we can run the DP detection after the HDMI detection has
already set the shared encoder's type. For now solve this keeping the
current behavior and running the detection in this case too. For a proper
solution Ville suggested to split the encoder into an HDMI and DP one, that
can be done as a follow-up.
This issue triggers the WARN in intel_display_port_aux_power_domain() and
was introduced in:
commit 25f78f58e5
Author: Ville Syrjälä <ville.syrjala@linux.intel.com>
Date: Mon Nov 16 15:01:04 2015 +0100
drm/i915: Clean up AUX power domain handling
CC: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
CC: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
[Cherry-picked from drm-intel-next-queued 651174a4 (Imre)]
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448643329-18675-4-git-send-email-imre.deak@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Currently the gmbus code uses intel_aux_display_runtime_get/put in an
effort to make sure the hardware is powered up sufficiently for gmbus.
That function only takes the runtime PM reference which on VLV/CHV/BXT
is not enough. We need the disp2d/pipe-a well on VLV/CHV and power well
2 on BXT. So add a new power domnain for gmbus and kill off the now
unused intel_aux_display_runtime_get/put. And change
intel_hdmi_set_edid() to use the gmbus power domain too since that's all
we need there.
Also toss in a BUILD_BUG_ON() to catch problems if we run out of
bits for power domains. We're already really close to the limit...
[Patrik: Add gmbus string to debugfs output]
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
[Cherry-picked from drm-intel-next-queued f0ab43e6 (Imre)]
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448643329-18675-3-git-send-email-imre.deak@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Linus Torvalds