[Intel-xe] [PATCH V9 4/6] drm/xe: Add timeslice duration engine property to sysfs

[Tejas Upadhyay]

Timeslices between multiple context is supported via
guc scheduling. Add sysfs entry to provide user defined
timeslice duration to guc scheduling.

The timeslice duration can be adjusted per-engine class using,

/sys/class/drm/cardX/device/tileN/gtN/engines/ccs/timeslice_duration_us

V7:
  - Rebase to use s/xe_engine/xe_hw_engine/ - Matt
V6:
  - Remove duration validation, not relevant - Niranjana
V5:
  - Rebase to replace hw engine with eclass interface
V4:
  - Rebase to per class engine props interface
V3:
  - Rebase
  - Update commit messge to add tile
V2:
  - Rebase

Signed-off-by: Tejas Upadhyay <tejas.upadhyay at intel.com>
---
 drivers/gpu/drm/xe/xe_hw_engine_class_sysfs.c | 30 +++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/drivers/gpu/drm/xe/xe_hw_engine_class_sysfs.c b/drivers/gpu/drm/xe/xe_hw_engine_class_sysfs.c
index 5e2dba0be8eb..b1c13d27bcf4 100644
--- a/drivers/gpu/drm/xe/xe_hw_engine_class_sysfs.c
+++ b/drivers/gpu/drm/xe/xe_hw_engine_class_sysfs.c
@@ -78,6 +78,35 @@ static ssize_t job_timeout_default(struct kobject *kobj,
 static struct kobj_attribute job_timeout_def =
 __ATTR(job_timeout_ms, 0444, job_timeout_default, NULL);
 
+static ssize_t timeslice_duration_store(struct kobject *kobj,
+					struct kobj_attribute *attr,
+					const char *buf, size_t count)
+{
+	struct xe_hw_engine_class_intf *eclass = kobj_to_eclass(kobj);
+	u32 duration;
+	int err;
+
+	err = kstrtou32(buf, 0, &duration);
+	if (err)
+		return err;
+
+	WRITE_ONCE(eclass->sched_props.timeslice_us, duration);
+
+	return count;
+}
+
+static ssize_t timeslice_duration_show(struct kobject *kobj,
+		struct kobj_attribute *attr, char *buf)
+{
+	struct xe_hw_engine_class_intf *eclass = kobj_to_eclass(kobj);
+
+	return sprintf(buf, "%u\n", eclass->sched_props.timeslice_us);
+}
+
+static struct kobj_attribute timeslice_duration_attr =
+	__ATTR(timeslice_duration_us, 0644, timeslice_duration_show,
+	       timeslice_duration_store);
+
 static ssize_t timeslice_default(struct kobject *kobj,
 				 struct kobj_attribute *attr, char *buf)
 {
@@ -110,6 +139,7 @@ static const struct attribute *defaults[] = {
 
 static const struct attribute *files[] = {
 	&job_timeout_attr.attr,
+	&timeslice_duration_attr.attr,
 	NULL
 };
 
-- 
2.25.1