[PATCH 5.6 147/254] drm/i915/gen12: Disable preemption timeout

From: Greg Kroah-Hartman
Date: Thu Apr 16 2020 - 10:27:43 EST


From: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx>

commit 07bcfd1291de77ffa9b627b4442783aba1335229 upstream.

Allow super long OpenCL workloads which cannot be preempted within
the default timeout to run out of the box.

v2:
* Make it stick out more and apply only to RCS. (Chris)

v3:
* Mention platform override in kconfig. (Joonas)

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx>
Cc: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx>
Cc: Michal Mrozek <michal.mrozek@xxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> # v5.6+
Acked-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Acked-by: Michal Mrozek <Michal.mrozek@xxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20200312115748.29970-1-tvrtko.ursulin@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/gpu/drm/i915/Kconfig.profile | 4 ++++
drivers/gpu/drm/i915/gt/intel_engine_cs.c | 13 +++++++++----
2 files changed, 13 insertions(+), 4 deletions(-)

--- a/drivers/gpu/drm/i915/Kconfig.profile
+++ b/drivers/gpu/drm/i915/Kconfig.profile
@@ -35,6 +35,10 @@ config DRM_I915_PREEMPT_TIMEOUT

May be 0 to disable the timeout.

+ The compiled in default may get overridden at driver probe time on
+ certain platforms and certain engines which will be reflected in the
+ sysfs control.
+
config DRM_I915_SPIN_REQUEST
int "Busywait for request completion (us)"
default 5 # microseconds
--- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
@@ -274,6 +274,7 @@ static void intel_engine_sanitize_mmio(s
static int intel_engine_setup(struct intel_gt *gt, enum intel_engine_id id)
{
const struct engine_info *info = &intel_engines[id];
+ struct drm_i915_private *i915 = gt->i915;
struct intel_engine_cs *engine;

BUILD_BUG_ON(MAX_ENGINE_CLASS >= BIT(GEN11_ENGINE_CLASS_WIDTH));
@@ -300,11 +301,11 @@ static int intel_engine_setup(struct int
engine->id = id;
engine->legacy_idx = INVALID_ENGINE;
engine->mask = BIT(id);
- engine->i915 = gt->i915;
+ engine->i915 = i915;
engine->gt = gt;
engine->uncore = gt->uncore;
engine->hw_id = engine->guc_id = info->hw_id;
- engine->mmio_base = __engine_mmio_base(gt->i915, info->mmio_bases);
+ engine->mmio_base = __engine_mmio_base(i915, info->mmio_bases);

engine->class = info->class;
engine->instance = info->instance;
@@ -319,11 +320,15 @@ static int intel_engine_setup(struct int
engine->props.timeslice_duration_ms =
CONFIG_DRM_I915_TIMESLICE_DURATION;

+ /* Override to uninterruptible for OpenCL workloads. */
+ if (INTEL_GEN(i915) == 12 && engine->class == RENDER_CLASS)
+ engine->props.preempt_timeout_ms = 0;
+
engine->context_size = intel_engine_context_size(gt, engine->class);
if (WARN_ON(engine->context_size > BIT(20)))
engine->context_size = 0;
if (engine->context_size)
- DRIVER_CAPS(gt->i915)->has_logical_contexts = true;
+ DRIVER_CAPS(i915)->has_logical_contexts = true;

/* Nothing to do here, execute in order of dependencies */
engine->schedule = NULL;
@@ -339,7 +344,7 @@ static int intel_engine_setup(struct int
gt->engine_class[info->class][info->instance] = engine;
gt->engine[id] = engine;

- gt->i915->engine[id] = engine;
+ i915->engine[id] = engine;

return 0;
}