On Tue, 29 Oct 2024 16:29:12 +0100
Boris Brezillon <boris.brezil...@collabora.com> wrote:
> Groups can be killed during a reset even though they did nothing wrong.
> That usually happens when the FW is put in a bad state by other groups,
> resulting in group suspension failures when the reset happens.
>
> If we end up in that situation, flag the group innocent and report
> innocence through a new DRM_PANTHOR_GROUP_STATE flag.
>
> Bump the minor driver version to reflect the uAPI change.
>
> Changes in v3:
> - Actually report innocence to userspace
>
> Changes in v2:
> - New patch
>
> Signed-off-by: Boris Brezillon <boris.brezil...@collabora.com>
> ---
> drivers/gpu/drm/panthor/panthor_drv.c | 2 +-
> drivers/gpu/drm/panthor/panthor_sched.c | 18 ++++++++++++++++++
> include/uapi/drm/panthor_drm.h | 9 +++++++++
> 3 files changed, 28 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/panthor/panthor_drv.c
> b/drivers/gpu/drm/panthor/panthor_drv.c
> index ac7e53f6e3f0..f1dff7e0173d 100644
> --- a/drivers/gpu/drm/panthor/panthor_drv.c
> +++ b/drivers/gpu/drm/panthor/panthor_drv.c
Forgot to update the changelog with:
--- a/drivers/gpu/drm/panthor/panthor_drv.c
+++ b/drivers/gpu/drm/panthor/panthor_drv.c
@@ -1493,6 +1493,7 @@ static void panthor_debugfs_init(struct drm_minor
*minor)
* - 1.1 - adds DEV_QUERY_TIMESTAMP_INFO query
* - 1.2 - adds DEV_QUERY_GROUP_PRIORITIES_INFO query
* - adds PANTHOR_GROUP_PRIORITY_REALTIME priority
+ * - 1.3 - adds DRM_PANTHOR_GROUP_STATE_INNOCENT flag
*/
I'll send a v4 addressing that, but I'll probably queue the first two
patches to drm-misc-fixes first.
> @@ -1507,7 +1507,7 @@ static const struct drm_driver panthor_drm_driver = {
> .desc = "Panthor DRM driver",
> .date = "20230801",
> .major = 1,
> - .minor = 2,
> + .minor = 3,
>
> .gem_create_object = panthor_gem_create_object,
> .gem_prime_import_sg_table = drm_gem_shmem_prime_import_sg_table,
> diff --git a/drivers/gpu/drm/panthor/panthor_sched.c
> b/drivers/gpu/drm/panthor/panthor_sched.c
> index ef4bec7ff9c7..97ed5fe5a191 100644
> --- a/drivers/gpu/drm/panthor/panthor_sched.c
> +++ b/drivers/gpu/drm/panthor/panthor_sched.c
> @@ -610,6 +610,16 @@ struct panthor_group {
> */
> bool timedout;
>
> + /**
> + * @innocent: True when the group becomes unusable because the group
> suspension
> + * failed during a reset.
> + *
> + * Sometimes the FW was put in a bad state by other groups, causing the
> group
> + * suspension happening in the reset path to fail. In that case, we
> consider the
> + * group innocent.
> + */
> + bool innocent;
> +
> /**
> * @syncobjs: Pool of per-queue synchronization objects.
> *
> @@ -2690,6 +2700,12 @@ void panthor_sched_suspend(struct panthor_device
> *ptdev)
> u32 csg_id = ffs(slot_mask) - 1;
> struct panthor_csg_slot *csg_slot =
> &sched->csg_slots[csg_id];
>
> + /* If the group was still usable before that point, we
> consider
> + * it innocent.
> + */
> + if (group_can_run(csg_slot->group))
> + csg_slot->group->innocent = true;
> +
> /* We consider group suspension failures as fatal and
> flag the
> * group as unusable by setting timedout=true.
> */
> @@ -3570,6 +3586,8 @@ int panthor_group_get_state(struct panthor_file *pfile,
> get_state->state |= DRM_PANTHOR_GROUP_STATE_FATAL_FAULT;
> get_state->fatal_queues = group->fatal_queues;
> }
> + if (group->innocent)
> + get_state->state |= DRM_PANTHOR_GROUP_STATE_INNOCENT;
> mutex_unlock(&sched->lock);
>
> group_put(group);
> diff --git a/include/uapi/drm/panthor_drm.h b/include/uapi/drm/panthor_drm.h
> index 87c9cb555dd1..b99763cbae48 100644
> --- a/include/uapi/drm/panthor_drm.h
> +++ b/include/uapi/drm/panthor_drm.h
> @@ -923,6 +923,15 @@ enum drm_panthor_group_state_flags {
> * When a group ends up with this flag set, no jobs can be submitted to
> its queues.
> */
> DRM_PANTHOR_GROUP_STATE_FATAL_FAULT = 1 << 1,
> +
> + /**
> + * @DRM_PANTHOR_GROUP_STATE_INNOCENT: Group was killed during a reset
> caused by other
> + * groups.
> + *
> + * This flag can only be set if DRM_PANTHOR_GROUP_STATE_TIMEDOUT is set
> and
> + * DRM_PANTHOR_GROUP_STATE_FATAL_FAULT is not.
> + */
> + DRM_PANTHOR_GROUP_STATE_INNOCENT = 1 << 2,
> };
>
> /**
