Commit Graph

1113 Commits

Author SHA1 Message Date
Michal Wajdeczko 93ffbe8e9d drm/i915/guc: Introduce USES_GUC_xxx helper macros
In the upcoming patch we will change the way how to recognize
when GuC is in use. Using helper macros will minimize scope
of that changes. While here, update dev_info message.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171206135316.32556-3-michal.wajdeczko@intel.com
2017-12-06 14:41:49 +00:00
Chris Wilson 8bd099a71d drm/i915: Tidy up signed/unsigned comparison
drivers/gpu/drm/i915/i915_irq.c|3096 col 29| error: comparison between signed and unsigned integer expressions [-Werror=sign-compare]

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171130125253.21405-1-chris@chris-wilson.co.uk
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
2017-11-30 17:34:44 +00:00
Sagar Arun Kamble c6dce8f140 drm/i915: Update execlists tasklet naming
intel_lrc_irq_handler and i915_guc_irq_handler are HW submission related
tasklet functions. Name them with "submission_tasklet" suffix and
remove intel/i915 prefix as they are static. Also rename irq_tasklet
as just tasklet for clarity.

v2: s/_bh/_tasklet (Chris)

Suggested-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Michal Winiarski <michal.winiarski@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/1510839162-25197-2-git-send-email-sagar.a.kamble@intel.com
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
2017-11-16 15:01:31 +00:00
Chris Wilson bcbd5c33a3 drm/i915/guc: Always enable the breadcrumbs irq
The execlists emulation on top of the GuC (used for scheduling and
preemption) depends on the MI_USER_INTERRUPT for its notifications and
tasklet action. As we always employ the irq, there is no advantage in
ever disabling it while we are using the GuC, so allow us to arm the
breadcrumb irq when enabling GuC submission and disarm upon disabling.
The impact should be lessened by the delayed irq disabling we do (we
only disable after receiving an interrupt for which no one was wanting),
but allowing guc to explicitly manage the irq in relation to itself is
simpler and prevents an issue with losing an interrupt for preemption
as it is not coupled to an active request.

Internally, we add a reference counter (breadcrumbs.irq_enabled) as a
simple mechanism to allow GuC to keep the breadcrumb irq enabled. To
improve upon always enabling the irq while guc is selected, we need
to hook into the parking facility of intel_engines so that we only enable
the breadcrumbs while the GT is active (one step better would be to
individually park/unpark each engine).

In effect, this means that we keep the breadcrumb irq always enabled for
the entire duration the guc is busy, whereas before we would try to
switch it off whenever we idled for more than interrupt with no
associated waiters. The difference *should* be negligible in practice!

v2: Stop abusing fence signaling (and its auxiliary data structures) to
enable the breadcrumbs irqs.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Michał Winiarski <michal.winiarski@intel.com>,
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: Michał Winiarski <michal.winiarski@intel.com>,
Link: https://patchwork.freedesktop.org/patch/msgid/20171025143943.7661-3-chris@chris-wilson.co.uk
2017-10-25 18:47:30 +01:00
Chris Wilson 4a118ecbe9 drm/i915: Filter out spurious execlists context-switch interrupts
Back in commit a4b2b01523 ("drm/i915: Don't mark an execlists
context-switch when idle") we noticed the presence of late
context-switch interrupts. We were able to filter those out by looking
at whether the ELSP remained active, but in commit beecec9017
("drm/i915/execlists: Preemption!") that became problematic as we now
anticipate receiving a context-switch event for preemption while ELSP
may be empty. To restore the spurious interrupt suppression, add a
counter for the expected number of pending context-switches and skip if
we do not need to handle this interrupt to make forward progress.

v2: Don't forget to switch on for preempt.
v3: Reduce the counter to a on/off boolean tracker. Declare the HW as
active when we first submit, and idle after the final completion event
(with which we confirm the HW says it is idle), and track each source
of activity separately. With a finite number of sources, it should aide
us in debugging which gets stuck.

Fixes: beecec9017 ("drm/i915/execlists: Preemption!")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michal Winiarski <michal.winiarski@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Arkadiusz Hiler <arkadiusz.hiler@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171023213237.26536-3-chris@chris-wilson.co.uk
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
2017-10-24 15:54:37 +01:00
Sagar Arun Kamble 562d9bae08 drm/i915: Name structure in dev_priv that contains RPS/RC6 state as "gt_pm"
Prepared substructure rps for RPS related state. autoenable_work is
used for RC6 too hence it is defined outside rps structure. As we do
this lot many functions are refactored to use intel_rps *rps to access
rps related members. Hence renamed intel_rps_client pointer variables
to rps_client in various functions.

v2: Rebase.

v3: s/pm/gt_pm (Chris)
Refactored access to rps structure by declaring struct intel_rps * in
many functions.

Signed-off-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Radoslaw Szwichtenberg <radoslaw.szwichtenberg@intel.com> #1
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/1507360055-19948-9-git-send-email-sagar.a.kamble@intel.com
Acked-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171010213010.7415-8-chris@chris-wilson.co.uk
2017-10-11 08:56:59 +01:00
Sagar Arun Kamble 9f817501bd drm/i915: Move rps.hw_lock to dev_priv and s/hw_lock/pcu_lock
In order to separate GT PM related functionality into new structure
we are updating rps structure. hw_lock in it is used for display
related PCU communication too hence move it to dev_priv.

Signed-off-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Radoslaw Szwichtenberg <radoslaw.szwichtenberg@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/1507360055-19948-8-git-send-email-sagar.a.kamble@intel.com
Acked-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171010213010.7415-7-chris@chris-wilson.co.uk
2017-10-11 08:56:56 +01:00
Sagar Arun Kamble ad1443f0f3 drm/i915: Name i915_runtime_pm structure in dev_priv as "runtime_pm"
We were using dev_priv->pm for runtime power management related state.
This patch renames it to "runtime_pm" which looks more apt.

v2: s/rpm/runtime_pm (Chris)

Signed-off-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Radoslaw Szwichtenberg <radoslaw.szwichtenberg@intel.com> #1
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/1507360055-19948-7-git-send-email-sagar.a.kamble@intel.com
Acked-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20171010213010.7415-6-chris@chris-wilson.co.uk
2017-10-11 08:56:54 +01:00
Mika Kahola 45c1cd8754 drm/i915: Cleanup South Error Interrupts
Cleanup and parametrize the handling of South Error Interrupts (SERR_INT).

Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Mika Kahola <mika.kahola@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1507630626-23806-6-git-send-email-mika.kahola@intel.com
2017-10-10 18:30:08 +03:00
Mika Kahola 0a195c0294 drm/i915: Fold IRQ pipe masks
Fold IRQ pipe masks into one loop instead of hardcoding per pipe.

Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Mika Kahola <mika.kahola@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1507630626-23806-4-git-send-email-mika.kahola@intel.com
2017-10-10 18:29:33 +03:00
Chris Wilson beecec9017 drm/i915/execlists: Preemption!
When we write to ELSP, it triggers a context preemption at the earliest
arbitration point (3DPRIMITIVE, some PIPECONTROLs, a few other
operations and the explicit MI_ARB_CHECK). If this is to the same
context, it triggers a LITE_RESTORE where the RING_TAIL is merely
updated (used currently to chain requests from the same context
together, avoiding bubbles). However, if it is to a different context, a
full context-switch is performed and it will start to execute the new
context saving the image of the old for later execution.

Previously we avoided preemption by only submitting a new context when
the old was idle. But now we wish embrace it, and if the new request has
a higher priority than the currently executing request, we write to the
ELSP regardless, thus triggering preemption, but we tell the GPU to
switch to our special preemption context (not the target). In the
context-switch interrupt handler, we know that the previous contexts
have finished execution and so can unwind all the incomplete requests
and compute the new highest priority request to execute.

It would be feasible to avoid the switch-to-idle intermediate by
programming the ELSP with the target context. The difficulty is in
tracking which request that should be whilst maintaining the dependency
change, the error comes in with coalesced requests. As we only track the
most recent request and its priority, we may run into the issue of being
tricked in preempting a high priority request that was followed by a
low priority request from the same context (e.g. for PI); worse still
that earlier request may be our own dependency and the order then broken
by preemption. By injecting the switch-to-idle and then recomputing the
priority queue, we avoid the issue with tracking in-flight coalesced
requests. Having tried the preempt-to-busy approach, and failed to find
a way around the coalesced priority issue, Michal's original proposal to
inject an idle context (based on handling GuC preemption) succeeds.

The current heuristic for deciding when to preempt are only if the new
request is of higher priority, and has the privileged priority of
greater than 0. Note that the scheduler remains unfair!

v2: Disable for gen8 (bdw/bsw) as we need additional w/a for GPGPU.
Since, the feature is now conditional and not always available when we
have a scheduler, make it known via the HAS_SCHEDULER GETPARAM (now a
capability mask).
v3: Stylistic tweaks.
v4: Appease Joonas with a snippet of kerneldoc, only to fuel to fire of
the preempt vs preempting debate.

Suggested-by: Michal Winiarski <michal.winiarski@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michal Winiarski <michal.winiarski@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Arkadiusz Hiler <arkadiusz.hiler@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Ben Widawsky <benjamin.widawsky@intel.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Zhi Wang <zhi.a.wang@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171003203453.15692-8-chris@chris-wilson.co.uk
2017-10-04 17:52:46 +01:00
Imre Deak 9dfe2e3ad3 drm/i915/gen8+: Init/reset display interrupts only if i915 IRQs are enabled
Only init / reset the display interrupts during power well enabling /
disabling if the i915 interrupts are enabled. So far we did the
init / reset during driver loading / resuming too, where
initialization / enabling of the i915 interrupts happens only at a later
point. This didn't cause a problem due to GEN8_MASTER_IRQ_CONTROL being
cleared, but triggered gen3_assert_iir_is_zero() in GEN8_IRQ_INIT_NDX().

References: https://bugs.freedesktop.org/show_bug.cgi?id=102988
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20170928100624.15533-1-imre.deak@intel.com
2017-10-02 12:09:11 +03:00
Rodrigo Vivi 163e8aecd1 drm/i915: Also discard second CRC on gen8+ platforms.
One of the differences I spotted for GEN8+ platforms when
compared to older platforms is that spec for BDW+ includes
this sentence:

"The first CRC done indication after CRC is first enabled is
from only a partial frame, so it will not have the expected
CRC result."

This is an indication that on BDW+ platforms, by the time
we receive the interrupt the CRC is not accurate yet for
the full frame. That would be ok, because we are already
skipping the first CRC for all platforms. However the comment
on the code state that it is for some unknown reason. Also,
on CHV (gen8 lp) we were already discarding the second CRC
as well to make sure we have a reliable CRC on hand.

So based on all ou tests and bugs it seems that it is not
on CHV that needs to discard 2 first CRCs, but all BDW+
platforms.

Starting on SKL we have this CRC done bit (24), but the
experiments around the use of this bit wasn't that stable
as just discarding the second CRC. So, let's for now
just move with CHV solution for all gen8+ platforms and
make our CI a bit more stable.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=102374
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101309
Cc: Mika Kahola <mika.kahola@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Tested-by: Mika Kahola <mika.kahola@intel.com>
Reviewed-by: Mika Kahola <mika.kahola@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170928002040.7917-1-rodrigo.vivi@intel.com
2017-09-28 09:41:48 -07:00
Uma Shankar aec0246f3e drm/i915: Enable scanline read based on frame timestamps
For certain platforms on certain encoders, timings are driven
from port instead of pipe. Thus, we can't rely on pipe scanline
registers to get the timing information. Some cases scanline
register read will not be functional.
This is causing vblank evasion logic to fail since it relies on
scanline, causing atomic update failure warnings.

This patch uses pipe framestamp and current timestamp registers
to calculate scanline. This is an indirect way to get the scanline.
It helps resolve atomic update failure for gen9 dsi platforms.

v2: Addressed Ville and Daniel's review comments. Updated the
register MACROs, handled race condition for register reads,
extracted timings from the hwmode. Removed the dependency on
crtc->config to get the encoder type.

v3: Made get scanline function generic

v4: Addressed Ville's review comments. Added a flag to decide timestamp
based scanline reporting. Changed 64bit variables to u32

v5: Adressed Ville's review comments. Put the scanline compute function
at the place of caller. Removed hwmode flags from uapi and used a local
i915 data structure instead.

v6: Used vblank hwmode to get the timings.

v7: Fixed sparse warnings, indentation and minor review comments.

v8: Limited this only for Gen9 DSI.

Credits-to: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Uma Shankar <uma.shankar@intel.com>
Signed-off-by: Chandra Konduru <chandra.konduru@intel.com>
Signed-off-by: Vidya Srinivas <vidya.srinivas@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1506347761-4201-1-git-send-email-vidya.srinivas@intel.com
2017-09-26 10:57:05 +03:00
Ville Syrjälä 6b12ca569b drm/i915: Don't rmw PIPESTAT enable bits
i830 seems to occasionally forget the PIPESTAT enable bits when
we read the register. These aren't the only registers on i830 that
have problems with RMW, as reading the double buffered plane
registers returns the latched value rather than the last written
value. So something similar is perhaps going on with PIPESTAT.

This corruption results on vblank interrupts occasionally turning off
on their own, which leads to vblank timeouts and generally a stuck
display subsystem.

So let's not RMW the pipestat enable bits, and instead use the cached
copy we have around.

Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170914151731.5034-1-ville.syrjala@linux.intel.com
Reviewed-by: Imre Deak <imre.deak@intel.com>
2017-09-25 16:54:09 +03:00
Mika Kuoppala b620e87021 drm/i915: Make own struct for execlist items
Engine's execlist related items have been increasing to
a point where a separate struct is warranted. Carve execlist
specific items to a dedicated struct to add clarity.

v2: add kerneldoc and fix whitespace (Joonas, Chris)
v3: csb_mmio changes, rebase
v4: s/\b(el|execlist)\b/execlists/ (Joonas)

Suggested-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Acked-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Michał Winiarski <michal.winiarski@intel.com> (v3)
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> (v3)
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170922124307.10914-1-mika.kuoppala@intel.com
2017-09-25 11:33:23 +03:00
Michal Wajdeczko 4f044a88a8 drm/i915: Rename global i915 to i915_modparams
Our global struct with params is named exactly the same way
as new preferred name for the drm_i915_private function parameter.
To avoid such name reuse lets use different name for the global.

v5: pure rename
v6: fix

Credits-to: Coccinelle

@@
identifier n;
@@
(
-	i915.n
+	i915_modparams.n
)

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Ville Syrjala <ville.syrjala@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Acked-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170919193846.38060-1-michal.wajdeczko@intel.com
2017-09-22 14:50:36 +03:00
Chris Wilson de4d2106f8 drm/i915: Check waiter->seqno carefully in case of preemption
If preemption occurs at precisely the right moment, we may decide that
the wait is complete even though the wait's request is no longer
executing (having been preempted). We handle this situation by double
checking that request following deciding whether the wait is complete.

Reported-by: Michał Winiarski <michal.winiarski@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michał Winiarski <michal.winiarski@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170918162734.21294-2-chris@chris-wilson.co.uk
Reviewed-by: Michał Winiarski <michal.winiarski@intel.com>
2017-09-22 12:47:19 +01:00
Chris Wilson 17b51ad8e5 drm/i915: Only wake the waiter from the interrupt if passed
As we now check if the seqno is complete in order to signal the fence,
we can also decide not to wake up the first_waiter until it is ready
(since it is waiting on the same seqno). The only caveat is that if we
need the engine->irq_seqno_barrier to enforce some coherency between an
interrupt and the seqno read, we have to always wake the waiter in order
to perform that heavyweight barrier.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170918162734.21294-1-chris@chris-wilson.co.uk
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
2017-09-22 12:46:57 +01:00
Rodrigo Vivi 3b92e263dd drm/i915/cnp: Display Wa #1179: WaHardHangonHotPlug
"CNL PCH chance of hang when software accesses south display
registers after hotplug is enabled.
Workaround: Program 0xC2000 bits 11:8 = 0xF before enabling
south display hotplug detection."

"Workaround only needs to be applied to pre-production steppings
used in graphics capable SKUs, but it is easier to apply to
everything, and does not hurt."

v2: Moving from clock gating to right before enabling
    SHOTPLUG_CTL as it should be.
v3: Align with SOUTH_CHICKEN1 (DK) and consequently use proper
    spaces on bits definition since other bits around already use
    new style. And now that checkpatch is not noise anymore I also
    fixed the reg read mask to avoid going over 80 chars.

Suggested-by: Ben Widawsky <ben@bwidawsk.net>
Cc: Ben Widawsky <ben@bwidawsk.net>
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170919215703.25947-1-rodrigo.vivi@intel.com
2017-09-19 16:04:56 -07:00
Ville Syrjälä 6bcdb1c839 drm/i915: Remove duplicated irq_preinstall/uninstall hooks
All the irq_preinstall and irq_uninstall hooks are now identical. Let's
just rename them all the irq_reset and remove the pointless duplicates.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170818183705.27850-16-ville.syrjala@linux.intel.com
2017-09-15 14:42:55 +03:00
Ville Syrjälä d420a50c21 drm/i915: Clean up the HWSTAM mess
Currently we're unmasking some random looking bits in HWSTAM
on gen3/4/5. The two bits we apparently unmask are 0 and 12,
and also bits 16-31 on gen4/5.
What those bits do depends on the gen as follows:
 bit 0: Breakpoint (gen2), ASLE (gen3), reserved (gen4), render user interrupt (gen5)
 bit 12: Sync flush statusa (gen2-4), reserved (gen5)
 bit 16-31: The ones that can unmasked seem to be mostly some
            display stuff on gen4. Bit 18 is the PIPE_CONTROL notify,
	    which might be the only intresting one. On gen5 all the
	    bits are reserved.

So I don't know whether we actually depend on that status page write
somehow. Extra seqno coherency by accident perhaps? Except we don't
even unmask the user interrupt bit in HWSTAM except on gen5, and
sync flush isn't something we use normally, so seems unlikely. So
let's just assume we don't need any of this and mask everything in
HWSTAM.

From gen6 onwards there's a separate HWSTAM for each engine, and so
we deal with them during the engine setup.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170818183705.27850-15-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
2017-09-15 14:42:55 +03:00
Chris Wilson e01e71fc49 drm/i915: Remove unused 'in_vbl' from i915_get_crtc_scanoutpos()
Commit 1bf6ad622b ("drm/vblank: drop the mode argument from
drm_calc_vbltimestamp_from_scanoutpos") removed the use of in_vbl, but
did not remove the local variable. Do so now.

Fixes: 1bf6ad622b ("drm/vblank: drop the mode argument from drm_calc_vbltimestamp_from_scanoutpos")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170914164213.18461-1-chris@chris-wilson.co.uk
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
2017-09-15 09:44:26 +01:00
Ville Syrjälä 5190707e7a drm/i915: Gen3 HWSTAM is actually 32 bits
Bspec claims that HWSTAM is only 16 bits on gen3, but the other
interrupts registers are 32 bits and there are 18 valid interrupt
bits. Hence a 16 bit HWSTAM wouldn't be able to contain all the
bits, so it seems the spec is incorrect about the size of the
register. And indeed I can clear bits 16 and 17 just fine with
a 32 bit write. So let's adjust the code to treat the register
as 32 bits.

Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170818183705.27850-14-ville.syrjala@linux.intel.com
2017-09-14 17:18:54 +03:00
Ville Syrjälä af722d280e drm/i915: Rewrite GMCH irq handlers to avoid loops
Eliminate the loops from the gen2-3 irq handlers. Since we don't use
MSI anymore on these platforms, and thus the CPU interrupt will be level
triggered, we shouldn't need to play any tricks with IER to induce edges
from IIR. IIR itself still detects only edges from PIPESTAT & co. on
gen4 but since IIR is double buffered and we only clear one bit per irq
handler invocation we can use the normal "clear PIPESTAT & co. -> clear
IIR" approach to ack the interrupts. On gen2 everything is level
triggered, and gen3 presumably follows either the gen2 or gen4 approach
since nothing else would really make sense.

v2: Drop the IER tricks since we no longer use MSI

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170818183705.27850-12-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
2017-09-14 17:15:51 +03:00
Ville Syrjälä eb64343ca6 drm/i915: Extract PIPESTAT irq handling into separate functions
Extract the gen2-4 PIPESTAT irq handling into separate functions just
like we already do on VLV/CHV.

We can share valleyview_pipestat_irq_ack() on all gmch platforms to
actually read and clear the PIPESTAT status bits, so let's rename
it to i9xx_pipestat_irq_ack().

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170818183705.27850-11-ville.syrjala@linux.intel.com
2017-09-14 17:14:20 +03:00
Ville Syrjälä 9515d7b8eb drm/i915: Remove NULL dev_priv checks from irq_uninstall
There should be no way to land in irq_uninstall without a
valid dev_priv. Let's kill off the remaining checks, which are
probably some kind of UMS leftovers. Not all the irq_uninstall
hooks even had them anymore.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170818183705.27850-10-ville.syrjala@linux.intel.com
2017-09-14 17:13:58 +03:00
Ville Syrjälä c30bb1fd38 drm/i915: Unify the appearance of gen3/4 irq_postistall hooks
Do the irq_mask/enable_mask setup in the same way on gen3/4, and also
reorder the steps to make the code more uniform.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170818183705.27850-9-ville.syrjala@linux.intel.com
2017-09-14 17:13:18 +03:00
Ville Syrjälä e13924a8c2 drm/i915: Eliminate PORT_HOTPLUG_EN setup from gen3/4 irq_postinstall
We've already cleared PORT_HOTPLUG_EN in the .irq_preinstall hook
so doing it again in the .irq_postinstall is pointless.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170818183705.27850-8-ville.syrjala@linux.intel.com
2017-09-14 17:12:38 +03:00
Ville Syrjälä 045cebd2e4 drm/i915: Setup EMR first on all gen2-4
Unify the appaerance of the gen2-4 irq postinstall hooks a little
bit by doing the EMR setup first on all the platforms.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170818183705.27850-7-ville.syrjala@linux.intel.com
2017-09-14 17:11:19 +03:00
Ville Syrjälä e9e9848a6b drm/i915: Introduce GEN2_IRQ_RESET/INIT
Unify the appearance of the gen2 irq code with the gen3+ code by
introducing the GEN2_IRQ_RESET/INIT macros.

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170818183705.27850-6-ville.syrjala@linux.intel.com
2017-09-14 17:10:29 +03:00
Ville Syrjälä ba7eb78932 drm/i915: Use GEN3_IRQ_RESET/INIT on gen3/4
Replace the manual IMR+IER+IIR write sequences with the appropriate
GEN3_IRQ_RESET/INIT macro invocations in gen3/4.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170818183705.27850-5-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
2017-09-14 17:09:55 +03:00
Ville Syrjälä 3488d4eb43 drm/i915: s/GEN5/GEN3/
The GEN5_IRQ_RESET/INIT macros are perfectly suitable even for
gen3/4 hardware as those have 32 bit interrupt registers. Let's
rename the macros to reflect that fact.

Gen2 on the other hand has 16 bit interrupt registers so these
macros aren't really appropriate there.

v2: Fix patch subject (Maarten)

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170818183705.27850-4-ville.syrjala@linux.intel.com
2017-09-14 17:09:09 +03:00
Ville Syrjälä 44d9241e3e drm/i915: Clear pipestat consistently
We have a lot of different ways of clearing the PIPESTAT registers.
Let's unify it all into one function. There's no magic in PIPESTAT
that would require any of the double clearing and whatnot that
some of the code tries to do. All we can really do is clear the status
bits and disable the enable bits. There is no way to mask anything
so as soon as another event happens the status bit will become set
again, and trying to clear them twice or something can't protect
against that.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170818183705.27850-3-ville.syrjala@linux.intel.com
Reviewed-by: Imre Deak <imre.deak@intel.com>
2017-09-14 17:09:06 +03:00
Ville Syrjälä 842ebf7aeb drm/i915: Don't enable/unmask flip interrupts
commit fd3a40242e ("drm/i915: Rip out legacy page_flip completion/irq
handling") removed the code to hande the flip done/pending interrupts,
but it failed to actually disable/mask those interrupts. Let's do that
now.

Also remove a stale comment that was left behind.

Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170818183705.27850-2-ville.syrjala@linux.intel.com
Reviewed-by: Imre Deak <imre.deak@intel.com>
2017-09-14 17:01:30 +03:00
Dhinakaran Pandiyan 4ebc65092c drm/i915/spt+: Don't reset invalid AUX channel interrupt bits in SDEIMR
The SDE interrupt bits 25, 26 and 27 are either reserved or meant for
DDI E hotplug in SPT+. These bits are meant for AUX channels only in LPT
and CPT, so add the appropriate checks.

Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170909004255.14827-1-dhinakaran.pandiyan@intel.com
2017-09-12 10:33:16 -07:00
Oscar Mateo 3814fd7769 drm/i915: Make some RPS functions static
They are not used anywhere else. Also, fix a small typo in a comment.

No functional changes.

Cc: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>
Reviewed-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1503532705-3692-1-git-send-email-oscar.mateo@intel.com
Link: https://patchwork.freedesktop.org/patch/msgid/1503532705-3692-1-git-send-email-oscar.mateo@intel.com
2017-08-24 12:36:18 -07:00
Daniel Vetter 9db529aac9 drm/i915: More surgically unbreak the modeset vs reset deadlock
There's no reason to entirely wedge the gpu, for the minimal deadlock
bugfix we only need to unbreak/decouple the atomic commit from the gpu
reset. The simplest way to fix that is by replacing the
unconditional fence wait a the top of commit_tail by a wait which
completes either when the fences are done (normal case, or when a
reset doesn't need to touch the display state). Or when the gpu reset
needs to force-unblock all pending modeset states.

The lesser source of deadlocks is when we try to pin a new framebuffer
and run into a stall. There's a bunch of places this can happen, like
eviction, changing the caching mode, acquiring a fence on older
platforms. And we can't just break the depency loop and keep going,
the only way would be to break out and restart. But the problem with
that approach is that we must stall for the reset to complete before
we grab any locks, and with the atomic infrastructure that's a bit
tricky. The only place is the ioctl code, and we don't want to insert
code into e.g. the BUSY ioctl. Hence for that problem just create a
critical section, and if any code is in there, wedge the GPU. For the
steady-state this should never be a problem.

Note that in both cases TDR itself keeps working, so from a userspace
pov this trickery isn't observable. Users themselvs might spot a short
glitch while the rendering is catching up again, but that's still
better than pre-TDR where we've thrown away all the rendering,
including innocent batches. Also, this fixes the regression TDR
introduced of making gpu resets deadlock-prone when we do need to
touch the display.

One thing I noticed is that gpu_error.flags seems to use both our own
wait-queue in gpu_error.wait_queue, and the generic wait_on_bit
facilities. Not entirely sure why this inconsistency exists, I just
picked one style.

A possible future avenue could be to insert the gpu reset in-between
ongoing modeset changes, which would avoid the momentary glitch. But
that's a lot more work to implement in the atomic commit machinery,
and given that we only need this for pre-g4x hw, of questionable
utility just for the sake of polishing gpu reset even more on those
old boxes. It might be useful for other features though.

v2: Rebase onto 4.13 with a s/wait_queue_t/struct wait_queue_entry/.

v3: Really emabarrassing fixup, I checked the wrong bit and broke the
unbreak/wakeup logic.

v4: Also handle deadlocks in pin_to_display.

v5: Review from Michel:
- Fixup the BUILD_BUG_ON
- Don't forget about the overlay

Cc: Michel Thierry <michel.thierry@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> (v2)
Cc: Michel Thierry <michel.thierry@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170808080828.23650-3-daniel.vetter@ffwll.ch
Reviewed-by: Michel Thierry <michel.thierry@intel.com>
2017-08-14 17:03:36 +02:00
Rodrigo Vivi 256cfdde42 drm/i915: Simplify hpd pin to port
We will soon need to make that pin port association per
platform, so let's try to simplify it beforehand.

Also we are moving the backwards port to pin
here as well so let's use a standardized way.

One extra possibility here would be to add a
MISSING_CASE along with PORT_NONE, but I don't want
to change this behaviour for now.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170811182650.14327-1-rodrigo.vivi@intel.com
2017-08-11 11:53:31 -07:00
Tvrtko Ursulin 03e0c83299 drm/i915: Remove unused i915_err_print_instdone
Just a simple code cleanup, below commit forgot to remove a
function which it made unused:

 commit eaa14c2486
 Author: Chris Wilson <chris@chris-wilson.co.uk>
 Date:   Wed Oct 19 13:52:03 2016 +0100

  drm/i915: Stop reporting error details in dmesg as well as the error-state

  As we already capture all the information from the registers into the
  error-state, also dumping that to dmesg just generates noise that upsets
  CI and users alike (and doesn't provide us with any more information).

v2: Chris Wilson dag out the relevant commit. Commit msg updated.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20170727110113.16942-1-tvrtko.ursulin@linux.intel.com
2017-07-28 11:19:36 +01:00
Chris Wilson 535275d323 drm/i915: Squelch reset messages during selftests
During our selftests, we try reseting the GPU tens of thousands of
times, flooding the dmesg with our reset spam drowning out any potential
warnings. Add an option to i915_reset()/i915_reset_engine() to specify a
quiet reset for selftesting.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20170721123238.16428-19-chris@chris-wilson.co.uk
Reviewed-by: Michel Thierry <michel.thierry@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2017-07-27 09:38:57 +02:00
Imre Deak 001bd2cb17 drm/i915/hsw, bdw: Add irq_pipe_mask, has_vga power well attributes
The pattern of a power well backing a set of pipe IRQ or VGA
functionality applies to all HSW+ platforms. Using power well attributes
instead of platform checks to decide whether to init/reset pipe IRQs and
VGA correspondingly is cleaner and it allows us to unify the HSW/BDW and
GEN9+ power well code in follow-up patches.

Also use u8 for pipe_mask in related helpers to match the type in the
power well struct.

v2:
- Use u8 instead of u32 for irq_pipe_mask. (Ville)

v3:
- Use u8 for pipe_mask in related helpers too for clarity.

Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Arkadiusz Hiler <arkadiusz.hiler@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170712155413.29839-1-imre.deak@intel.com
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2017-07-27 09:38:53 +02:00
Daniel Vetter 64282ea2d2 Merge airlied/drm-next into drm-intel-next-queued
Resync with upstream to avoid git getting too badly confused. Also, we
have a conflict with the drm_vblank_cleanup removal, which cannot be
resolved by simply taking our side. Bake that in properly.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2017-07-27 09:33:49 +02:00
Daniel Vetter af05559854 Merge airlied/drm-next into drm-misc-next
I need this to be able to apply the deferred fbdev setup patches, I
need the relevant prep work that landed through the drm-intel tree.

Also squash in conflict fixup from Laurent Pinchart.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2017-07-26 13:43:33 +02:00
Daniel Vetter fd3a40242e drm/i915: Rip out legacy page_flip completion/irq handling
All these races and things are now solved through the vblank evasion
trick, plus event handling is done using normal vblank even processing
and drm_crtc_arm_vblank_event. We can get rid of all this complexity.

Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170720175754.30751-5-daniel.vetter@ffwll.ch
2017-07-20 22:45:14 +02:00
Pandiyan, Dhinakaran bca2bf2a8f drm/i915: s/INTEL_INFO(dev_priv)->gen/INTEL_GEN(dev_priv) in i915_irq
INTEL_GEN() appears to be the new way of doing these platform checks, so
convert this i915_irq.c too.

Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1500402480-30741-1-git-send-email-dhinakaran.pandiyan@intel.com
2017-07-20 11:02:07 +01:00
Matthias Kaehlcke a21960339c drm/i915: Consistently use enum pipe for PCH transcoders
The current code uses in some instances enum transcoder for PCH
transcoders and enum pipe in others. This is error prone and clang
raises warnings like this:

drivers/gpu/drm/i915/intel_dp.c:3546:51: warning: implicit conversion
  from enumeration type 'enum pipe' to different enumeration type
  'enum transcoder' [-Wenum-conversion]
    intel_set_pch_fifo_underrun_reporting(dev_priv, PIPE_A, false);

Consistently use the type enum pipe for PCH transcoders.

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20170717181403.57324-1-mka@chromium.org
2017-07-18 08:39:03 +02:00
Chris Wilson 7b92c1bd05 drm/i915: Avoid keeping waitboost active for signaling threads
Once a client has requested a waitboost, we keep that waitboost active
until all clients are no longer waiting. This is because we don't
distinguish which waiter deserves the boost. However, with the advent of
fence signaling, the signaler threads appear as waiters to the RPS
interrupt handler. So instead of using a single boolean to track when to
keep the waitboost active, use a counter of all outstanding waitboosted
requests.

At this point, I have removed all vestiges of the rate limiting on
clients. Whilst this means that compositors should remain more fluid,
it also means that boosts are more prevalent. See commit b29c19b645
("drm/i915: Boost RPS frequency for CPU stalls") for a longer discussion
on the pros and cons of both approaches.

A drawback of this implementation is that it requires constant request
submission to keep the waitboost trimmed (as it is now cancelled when the
request is completed). This will be fine for a busy system, but near
idle the boosts may be kept for longer than desired (effectively tens of
vblanks worstcase) and there is a reliance on rc6 instead.

v2: Remove defunct rps.client_lock

Reported-by: Michał Winiarski <michal.winiarski@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michał Winiarski <michal.winiarski@intel.com>
Reviewed-by: Michał Winiarski <michal.winiarski@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170628123548.9236-1-chris@chris-wilson.co.uk
2017-06-28 15:23:12 +01:00
Sean Paul b740e76936 Merge remote-tracking branch 'airlied/drm-next' into drm-misc-next
Required for Daniel's drm_vblank_cleanup cleanup
2017-06-27 09:18:17 -04:00
Chris Wilson 36703e79a9 drm/i915: Break modeset deadlocks on reset
Trying to do a modeset from within a reset is fraught with danger. We
can fall into a cyclic deadlock where the modeset is waiting on a
previous modeset that is waiting on a request, and since the GPU hung
that request completion is waiting on the reset. As modesetting doesn't
allow its locks to be broken and restarted, or for its *own* reset
mechanism to take over the display, we have to do something very
evil instead. If we detect that we are stuck waiting to prepare the
display reset (by using a very simple timeout), resort to cancelling all
in-flight requests and throwing the user data into /dev/null, which is
marginally better than the driver locking up and keeping that data to
itself.

This is not a fix; this is just a workaround that unbreaks machines
until we can resolve the deadlock in a way that doesn't lose data!

v2: Move the retirement from set-wegded to the i915_reset() error path,
after which we no longer any delayed worker cleanup for
i915_handle_error()
v3: C abuse for syntactic sugar
v4: Cover all waits with the timeout to catch more driver breakage

References: https://bugs.freedesktop.org/show_bug.cgi?id=99093
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170622105625.16952-1-chris@chris-wilson.co.uk
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
2017-06-23 13:41:55 +01:00