[PATCH 4/8] drm/panthor: Add GROUP_KICK ioctl

[Mihail Atanassov]

From: Ketil Johnsen <ketil.johnsen at arm.com>

In the kernel submission flow, GROUP_SUBMIT will ensure that the group
gets assigned to a CSG. Conversely for the user submission flow, work
gets added to the ring buffer without kernel supervision, so there needs
to be a mechanism to trigger rescheduling. Use a new GROUP_KICK ioctl,
to keep it distinct from the existing submit flow.

Signed-off-by: Ketil Johnsen <ketil.johnsen at arm.com>
Signed-off-by: Mihail Atanassov <mihail.atanassov at arm.com>
---
 drivers/gpu/drm/panthor/panthor_drv.c   | 12 +++++++++++
 drivers/gpu/drm/panthor/panthor_sched.c | 27 +++++++++++++++++++++++++
 drivers/gpu/drm/panthor/panthor_sched.h |  1 +
 3 files changed, 40 insertions(+)

diff --git a/drivers/gpu/drm/panthor/panthor_drv.c b/drivers/gpu/drm/panthor/panthor_drv.c
index e391ab6aaab2..ce2fdcd3fb42 100644
--- a/drivers/gpu/drm/panthor/panthor_drv.c
+++ b/drivers/gpu/drm/panthor/panthor_drv.c
@@ -1305,6 +1305,17 @@ static int panthor_ioctl_vm_get_state(struct drm_device *ddev, void *data,
 	return 0;
 }
 
+static int panthor_ioctl_group_kick(struct drm_device *ddev, void *data,
+				    struct drm_file *file)
+{
+	struct drm_panthor_group_kick *args = data;
+	struct panthor_file *pfile = file->driver_priv;
+
+	panthor_sched_kick(pfile, args->handle, args->queue_mask);
+
+	return 0;
+}
+
 static int
 panthor_open(struct drm_device *ddev, struct drm_file *file)
 {
@@ -1375,6 +1386,7 @@ static const struct drm_ioctl_desc panthor_drm_driver_ioctls[] = {
 	PANTHOR_IOCTL(TILER_HEAP_CREATE, tiler_heap_create, DRM_RENDER_ALLOW),
 	PANTHOR_IOCTL(TILER_HEAP_DESTROY, tiler_heap_destroy, DRM_RENDER_ALLOW),
 	PANTHOR_IOCTL(GROUP_SUBMIT, group_submit, DRM_RENDER_ALLOW),
+	PANTHOR_IOCTL(GROUP_KICK, group_kick, DRM_RENDER_ALLOW),
 };
 
 static int panthor_mmap(struct file *filp, struct vm_area_struct *vma)
diff --git a/drivers/gpu/drm/panthor/panthor_sched.c b/drivers/gpu/drm/panthor/panthor_sched.c
index 471bb8f2b44c..3b56526a4b97 100644
--- a/drivers/gpu/drm/panthor/panthor_sched.c
+++ b/drivers/gpu/drm/panthor/panthor_sched.c
@@ -2845,6 +2845,33 @@ void panthor_sched_post_reset(struct panthor_device *ptdev, bool reset_failed)
 	}
 }
 
+void panthor_sched_kick(struct panthor_file *pfile, u32 group_handle, u32 queue_mask)
+{
+	struct panthor_group_pool *gpool = pfile->groups;
+	struct panthor_scheduler *sched = pfile->ptdev->scheduler;
+	struct panthor_group *group;
+
+	group = group_get(xa_load(&gpool->xa, group_handle));
+	if (!group)
+		return;
+
+	if (!group->queue_count)
+		goto err_put_group;
+
+	mutex_lock(&sched->lock);
+
+	if (group->csg_id < 0)
+		group_schedule_locked(group, queue_mask);
+	else
+		/* All queues share same doorbell page (for now), so we just need to ding one */
+		gpu_write(pfile->ptdev, CSF_DOORBELL(group->queues[0]->doorbell_id), 1);
+
+	mutex_unlock(&sched->lock);
+
+err_put_group:
+	group_put(group);
+}
+
 static void group_sync_upd_work(struct work_struct *work)
 {
 	struct panthor_group *group =
diff --git a/drivers/gpu/drm/panthor/panthor_sched.h b/drivers/gpu/drm/panthor/panthor_sched.h
index 0b3a2ee2a0ad..18fb7ad0952e 100644
--- a/drivers/gpu/drm/panthor/panthor_sched.h
+++ b/drivers/gpu/drm/panthor/panthor_sched.h
@@ -48,5 +48,6 @@ void panthor_sched_report_mmu_fault(struct panthor_device *ptdev);
 void panthor_sched_report_fw_events(struct panthor_device *ptdev, u32 events);
 
 u8 panthor_sched_doorbell_id(struct panthor_file *pfile, u32 group_handle);
+void panthor_sched_kick(struct panthor_file *pfile, u32 group_handle, u32 queue_mask);
 
 #endif
-- 
2.45.0