On wedging, we mark all executing requests as complete and all pending
requests completed as soon as they are ready. Before unwedging though we
wish to flush those pending requests prior to restoring default
execution, and so we must wait. Do so uninterruptibly as we do not provide
the EINTR gracefully back to userspace in this case but persists in
keeping the permanently wedged state without restarting the syscall.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190208153708.20023-4-chris@chris-wilson.co.uk
Previously, we were able to rely on the recursive properties of
struct_mutex to allow us to serialise revoking mmaps and reacquiring the
FENCE registers with them being clobbered over a global device reset.
I then proceeded to throw out the baby with the bath water in order to
pursue a struct_mutex-less reset.
Perusing LWN for alternative strategies, the dilemma on how to serialise
access to a global resource on one side was answered by
https://lwn.net/Articles/202847/ -- Sleepable RCU:
1 int readside(void) {
2 int idx;
3 rcu_read_lock();
4 if (nomoresrcu) {
5 rcu_read_unlock();
6 return -EINVAL;
7 }
8 idx = srcu_read_lock(&ss);
9 rcu_read_unlock();
10 /* SRCU read-side critical section. */
11 srcu_read_unlock(&ss, idx);
12 return 0;
13 }
14
15 void cleanup(void)
16 {
17 nomoresrcu = 1;
18 synchronize_rcu();
19 synchronize_srcu(&ss);
20 cleanup_srcu_struct(&ss);
21 }
No more worrying about stop_machine, just an uber-complex mutex,
optimised for reads, with the overhead pushed to the rare reset path.
However, we do run the risk of a deadlock as we allocate underneath the
SRCU read lock, and the allocation may require a GPU reset, causing a
dependency cycle via the in-flight requests. We resolve that by declaring
the driver wedged and cancelling all in-flight rendering.
v2: Use expedited rcu barriers to match our earlier timing
characteristics.
v3: Try to annotate locking contexts for sparse
v4: Reduce selftest lock duration to avoid a reset deadlock with fences
v5: s/srcu/reset_backoff_srcu/
v6: Remove more stale comments
Testcase: igt/gem_mmap_gtt/hang
Fixes: eb8d0f5af4 ("drm/i915: Remove GPU reset dependence on struct_mutex")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190208153708.20023-2-chris@chris-wilson.co.uk
Planes scanning out C8 will want to use the legacy lut as
their palette. That means the LUT content are unlikely to
be useful for gamma correction on other planes. Thus we
should disable pipe gamma for all the other planes. And
we should reject any non legacy LUT configurations when
C8 planes are present.
Fixes the appearance of the hw cursor when running
X -depth 8.
Note that CHV with it's independent CGM degamma/gamma LUTs
could probably use the CGM for gamma correction even when
the legacy LUT is used for C8. But that would require a
new uapi for configuring the legacy LUT and CGM LUTs at
the same time. Totally not worth it.
v2: Fix typo (Uma)
Rebase
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190207202146.26423-7-ville.syrjala@linux.intel.com
The pipe internal precision is higher than what we currently program to
the degamma/gamma LUTs. We can get a higher quality image by bypassing
the LUTs when they're not needed. Let's do that.
Each plane has its own control bit for this, so we have to update
all active planes. The way we've done this we don't actually have
to run through the whole .check_plane() thing. And we actually
do the .color_check() after .check_plane() so we couldn't even do
that without shuffling the code around.
Additionally on pre-skl we have to update the primary plane regardless
of whether it's active or not on account of the primary plane gamma
enable bit also affecting the pipe bottom color.
v2: Drop the '.' from patch title (Uma)
Fix 'primayr' typo (Uma,Matt)
Rebase
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190207202146.26423-5-ville.syrjala@linux.intel.com
Track whether pipe gamma is enabled or disabled. For now we
stick to the current behaviour of always enabling gamma. But
we do get working state readout for this now. On SKL+ we use
the pipe bottom color as our hardware state. On pre-SKL we
read the state back from the primary plane control register.
That only really correct for g4x+, as older platforms never
gamma correct pipe bottom color. But doing the readout the
same way on all platforms is fine, and there is no other way
to do it really.
v2: Initialize val at declaration (Uma)
Drop the bogus skl scaler comment change (Uma)
Rebase
v3: Allow fastboot with gamma_enable changes (Maarten)
v4: Drop the PIPE_BOTTOM_COLOR write from
intel_update_pipe_config() again. It snuck back in
during the rebase
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190207203913.5529-1-ville.syrjala@linux.intel.com
Changing the i915_edp_psr_debug was enabling, disabling or switching
PSR version by directly calling intel_psr_disable_locked() and
intel_psr_enable_locked(), what is not the default PSR path that will
be executed by real users.
So lets force a fastset in the PSR CRTC to trigger a pipe update and
stress the default code path.
Recently a bug was found when switching from PSR2 to PSR1 while
enable_psr kernel parameter was set to the default parameter, this
changes fix it and also fixes the bug linked bellow were DRRS was
left enabled together with PSR when enabling PSR from debugfs.
v2: Handling missing case: disabled to PSR1
v3: Not duplicating the whole atomic state(Maarten)
v4: Adding back the missing call to intel_psr_irq_control(Dhinakaran)
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=108341
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190206211845.5322-1-jose.souza@intel.com
Split the color management hooks along the single vs. double
buffered registers line. Of the currently programmed registers
GAMMA_MODE and the ilk+ pipe CSC are double buffered, the
LUTS and CHV CGM block are single buffered.
The double buffered register will be programmed during the
normal pipe update with evasion, and also during pipe enable
so that the settings will already be correct when the pipe
starts up before the planes are enabled.
The single buffered registers are currently programmed before
the vblank evade. Which is totally wrong, but we'll correct
that later.
v2: Add some docs to explain the two vfuncs (Matt,Uma)
Rebase
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190205160848.24662-6-ville.syrjala@linux.intel.com
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
On g4x+ the pipe gamma enable bit for the primary plane affects
the pipe bottom color as well. The same for the pipe csc enable
bit on ilk+. Thus we must configure those bits correctly even
when the primary plane is disabled.
To make the feasible let's split those settings from the
plane_ctl() function into a seprate funciton that we can
call from the ->disable_plane() hook as well.
For consistency we'll do that on all the plane types. While
that has no real benefits at this time, it'll become useful
when we start to control the pipe gamma/csc enable bits
dynamically when we overhaul the color management code.
On pre-g4x there doesn't appear to be any way to gamma
correct the pipe bottom color, but sticking to the same
pattern doesn't hurt. And it'll still help us to do
crtc state readout correctly for the pipe gamma enable
bit for the color management overhaul.
An alternative apporach would be to still precompute these
bits into plane_state->ctl, but that would require that we
run through the plane check even when the plane isn't logically
enabled on any crtc. Currently that condition causes us to
short circuit the entire thing and not call ->check_plane().
There would also be some chicken and egg problems with
->check_plane() vs. crtc color state check that would
requite splitting certain things into multiple steps.
So all in all this seems like the easier route.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190205160848.24662-2-ville.syrjala@linux.intel.com
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
update_wm_post is meant for pre-g4x only. Don't ever set
it on g4x+.
The only effect of a bogus update_wm_post on g4x+ could
be that we clear the legacy_cursor_update flag in
intel_atomic_commit(). Since legacy_cursor_update is
only set for legacy cursor updates (as the name suggests)
and we only set update_wm_post for a modeset the two
cases should never occur at the same time. But let's
be consistent in setting update_wm_post so we don't
end up confusing so many people.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190206185433.8116-1-ville.syrjala@linux.intel.com
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Apply backpressure to hogs that emit requests faster than the GPU can
process them by waiting for their ring to be less than half-full before
proceeding with taking the struct_mutex.
This is a gross hack to apply throttling backpressure, the long term
goal is to remove the struct_mutex contention so that each client
naturally waits, preferably in an asynchronous, nonblocking fashion
(pipelined operations for the win), for their own resources and never
blocks another client within the driver at least. (Realtime priority
goals would extend to ensuring that resource contention favours high
priority clients as well.)
This patch only limits excessive request production and does not attempt
to throttle clients that block waiting for eviction (either global GTT or
system memory) or any other global resources, see above for the long term
goal.
No microbenchmarks are harmed (to the best of my knowledge).
Testcase: igt/gem_exec_schedule/pi-ringfull-*
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190207071829.5574-1-chris@chris-wilson.co.uk
We have a bad habit of calling drm_fb_helper_hotplug_event() far more
then we actually need to. MST appears to be one of these cases, where we
call drm_fb_helper_hotplug_event() if we fail to resume a connected MST
topology in intel_dp_mst_resume(). We don't actually need to do this at
all though since hotplug events are already sent from
drm_dp_connector_destroy_work() every time connectors are unregistered
from userspace's PoV. Additionally, extra calls to
drm_fb_helper_hotplug_event() also just mean more of a chance of doing a
connector probe somewhere we shouldn't.
So, don't send any hotplug events during resume if the MST topology
fails to come up. Just rely on the DP MST helpers to send them for us.
Signed-off-by: Lyude Paul <lyude@redhat.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190129191001.442-3-lyude@redhat.com
When resuming, we check whether or not any previously connected
MST topologies are still present and if so, attempt to resume them. If
this fails, we disable said MST topologies and fire off a hotplug event
so that userspace knows to reprobe.
However, sending a hotplug event involves calling
drm_fb_helper_hotplug_event(), which in turn results in fbcon doing a
connector reprobe in the caller's thread - something we can't do at the
point in which i915 calls drm_dp_mst_topology_mgr_resume() since
hotplugging hasn't been fully initialized yet.
This currently causes some rather subtle but fatal issues. For example,
on my T480s the laptop dock connected to it usually disappears during a
suspend cycle, and comes back up a short while after the system has been
resumed. This guarantees pretty much every suspend and resume cycle,
drm_dp_mst_topology_mgr_set_mst(mgr, false); will be caused and in turn,
a connector hotplug will occur. Now it's Rute Goldberg time: when the
connector hotplug occurs, i915 reprobes /all/ of the connectors,
including eDP. However, eDP probing requires that we power on the panel
VDD which in turn, grabs a wakeref to the appropriate power domain on
the GPU (on my T480s, this is the PORT_DDI_A_IO domain). This is where
things start breaking, since this all happens before
intel_power_domains_enable() is called we end up leaking the wakeref
that was acquired and never releasing it later. Come next suspend/resume
cycle, this causes us to fail to shut down the GPU properly, which
causes it not to resume properly and die a horrible complicated death.
(as a note: this only happens when there's both an eDP panel and MST
topology connected which is removed mid-suspend. One or the other seems
to always be OK).
We could try to fix the VDD wakeref leak, but this doesn't seem like
it's worth it at all since we aren't able to handle hotplug detection
while resuming anyway. So, let's go with a more robust solution inspired
by nouveau: block fbdev from handling hotplug events until we resume
fbdev. This allows us to still send sysfs hotplug events to be handled
later by user space while we're resuming, while also preventing us from
actually processing any hotplug events we receive until it's safe.
This fixes the wakeref leak observed on the T480s and as such, also
fixes suspend/resume with MST topologies connected on this machine.
Changes since v2:
* Don't call drm_fb_helper_hotplug_event() under lock, do it after lock
(Chris Wilson)
* Don't call drm_fb_helper_hotplug_event() in
intel_fbdev_output_poll_changed() under lock (Chris Wilson)
* Always set ifbdev->hpd_waiting (Chris Wilson)
Signed-off-by: Lyude Paul <lyude@redhat.com>
Fixes: 0e32b39cee ("drm/i915: add DP 1.2 MST support (v0.7)")
Cc: Todd Previte <tprevite@gmail.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: intel-gfx@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v3.17+
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190129191001.442-2-lyude@redhat.com
Enable count array is supposed to have one counter for each possible
engine sampler. As such, array sizing and bounds checking is not correct
and would blow up the asserts if more samplers were added.
No ill-effect in the current code base but lets fix it for correctness.
At the same time tidy the assert for readability and robustness.
v2:
* One check per assert. (Chris Wilson)
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Fixes: b46a33e271 ("drm/i915/pmu: Expose a PMU interface for perf queries")
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20190205130353.21105-1-tvrtko.ursulin@linux.intel.com
Certain SNB machines (eg. ASUS K53SV) seem to have a broken BIOS
which misprograms the hardware badly when encountering a suitably
high resolution display. The programmed pipe timings are somewhat
bonkers and the DPLL is totally misprogrammed (P divider == 0).
That will result in atomic commit timeouts as apparently the pipe
is sufficiently stuck to not signal vblank interrupts.
IIRC something like this was also observed on some other SNB
machine years ago (might have been a Dell XPS 8300) but a BIOS
update cured it. Sadly looks like this was never fixed for the
ASUS K53SV as the latest BIOS (K53SV.320 11/11/2011) is still
broken.
The quickest way to deal with this seems to be to shut down
the pipe+ports+DPLL. Unfortunately doing this during the
normal sanitization phase isn't quite soon enough as we
already spew several WARNs about the bogus hardware state.
But it's better than hanging the boot for a few dozen seconds.
Since this is limited to a few old machines it doesn't seem
entirely worthwile to try and rework the readout+sanitization
code to handle it more gracefully.
v2: Fix potential NULL deref (kbuild test robot)
Constify has_bogus_dpll_config()
Cc: stable@vger.kernel.org # v4.20+
Cc: Daniel Kamil Kozar <dkk089@gmail.com>
Reported-by: Daniel Kamil Kozar <dkk089@gmail.com>
Tested-by: Daniel Kamil Kozar <dkk089@gmail.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=109245
Fixes: 516a49cc19 ("drm/i915: Fix assert_plane() warning on bootup with external display")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190111174950.10681-1-ville.syrjala@linux.intel.com
Reviewed-by: Mika Kahola <mika.kahola@intel.com>
(cherry picked from commit 7bed8adcd9)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190205141846.6053-1-ville.syrjala@linux.intel.com
Since we now have an easy way of refcounting drm_dp_mst_port structs and
safely accessing their contents, there isn't any good reason to keep
validating ports here. It doesn't prevent us from performing modesets on
branch devices that have been removed either, and we already disallow
enabling new displays on unregistered connectors in
update_connector_routing() in drm_atomic_check_modeset(). All it does is
cause us to have to make weird special exceptions in our atomic
modesetting code. So, get rid of it entirely.
Signed-off-by: Lyude Paul <lyude@redhat.com>
Fixes: eceae14724 ("drm/dp_mst: Start tracking per-port VCPI allocations")
Reviewed-by: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20190202002023.29665-3-lyude@redhat.com
When adding the early latency==0 check back I neglected to
realize that we no longer have a way to return a failure
from the wm computation like we had in the past (since we
now calculate wms before ddb allocations). Also plane_en
being false doesn't actually indicate that the level is
invalid as it wil also happen when the plane is not
enabled.
skl_allocate_pipe_ddb() starts scanning from the maximum
watermark level and it stops as soon as it finds a level
that is deemed viable. The assumption being that if level
n+1 is valid then level n is valid as well. Thus if we
now disable any watermark level by zeroing its latency
the code will think that level to be actually valid
and won't confirm whether the actually enabled lower
watermark level(s) actually fit into the allotted ddb
space. This results in hilarious watermark values that
exceed the ddb allocation of the plane.
The way we must now indicate a failure is to assign an
unreasoanbly big value to min_ddb_alloc which will then
make skl_allocate_pipe_ddb() reject the entire level.
v2: Also do the same for the lines>31 case (Matt)
v3: Make 'blocks' u32 (Matt)
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190205155053.10081-1-ville.syrjala@linux.intel.com
clear_intel_crtc_state() uses the stack for saving a temporary copy of
certain bits of the inherited crtc_state before clearing the unwanted
bits. This pushes it over the stack limit for my little 32b Pineview,
so move the temporary allocation to the heap instead. As we now use a
zeroed struct, we can copy the whole extended state back to both
preserve what bits need to be preserved and zero the rest.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190205092759.16018-1-chris@chris-wilson.co.uk
We generally omit register polling from the i915_reg_rw tracepoint.
Understandable since polling could generate a lot of noise in the
trace. The downside is that the trace is incomplete. As a compromise
let's trace the final register value observed while polling. That
should be generally sufficient to observe what the code should be
doing next.
I suppose in some cases it might make sense to also trace the initial
register value, and maybe the number of times we polled. But that
would require a separate tracepoint so let's leave it for the future.
The other users of _NOTRACE() are i915_pmu and i2c bitbanging,
which I decided to leave alone.
Next we should do something to claw back the tracepoints for
planes and whatnot which were switched to _FW() a while back.
I guess just new macros for raw_rw+trace. The question is
what to call it?
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190204211644.21967-1-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
First of all GMCH can be considered a feature by itself
since it is a chip present in some platforms that connects
the IA processor to memory and other components in PC.
Also with the introduction of display block at device info,
we got a redundant definition:
.display.has_gmch_display = 1,
So, let's clean up things a bit and use the standardized
way of has_feature on displays side.
No functional change and no manual interaction to generate
this patch.
It is only:
sed -si -e 's/has_gmch_display/has_gmch/g' \
-e 's/HAS_GMCH_DISPLAY/HAS_GMCH/g' drivers/gpu/drm/i915/*{c,h}
Cc: José Roberto de Souza <jose.souza@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190204222538.15842-1-rodrigo.vivi@intel.com