On a job timeout the NPU AXI master can be left wedged with
outstanding transactions. rocket_reset() detached the IOMMU group
before resetting the hardware, so iommu_detach_group() ->
__iommu_group_set_core_domain() asked the rk_iommu to stall and wait
for the in-flight transactions to drain. They never did, the stall
request timed out (-ETIMEDOUT) and the IOMMU core WARNed:
WARNING: drivers/iommu/iommu.c:157 __iommu_group_set_core_domain
iommu_detach_group
rocket_reset
rocket_job_timedout
Assert the core reset first: it quiesces the AXI master so the
following IOMMU detach completes cleanly. Move the detach after
rocket_core_reset() and out of the job_lock (it does not touch
in_flight_job).
Signed-off-by: Midgy BALON <[email protected]>
---
drivers/accel/rocket/rocket_job.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/drivers/accel/rocket/rocket_job.c
b/drivers/accel/rocket/rocket_job.c
index ac51bff39833f..e25234261536b 100644
--- a/drivers/accel/rocket/rocket_job.c
+++ b/drivers/accel/rocket/rocket_job.c
@@ -364,14 +364,20 @@ rocket_reset(struct rocket_core *core, struct
drm_sched_job *bad)
if (core->in_flight_job)
pm_runtime_put_noidle(core->dev);
- iommu_detach_group(NULL, core->iommu_group);
-
core->in_flight_job = NULL;
}
- /* Proceed with reset now. */
+ /*
+ * Reset the NPU hardware before detaching the IOMMU. A timed-out job
+ * leaves the NPU AXI master wedged; detaching the IOMMU then issues a
+ * stall request that never drains and times out (warning in the IOMMU
+ * core). Asserting the core reset first quiesces the master so the
+ * detach completes cleanly.
+ */
rocket_core_reset(core);
+ iommu_detach_group(NULL, core->iommu_group);
+
/* NPU has been reset, we can clear the reset pending bit. */
atomic_set(&core->reset.pending, 0);
--
2.39.5
