[PATCH] drm/imagination: Propagate all errors from KCCB command submission code

From: Alexandru Dadu

Date: Tue Aug 11 2026 - 02:13:35 EST


From: Alessio Belle <alessio.belle@xxxxxxxxxx>

pvr_kccb_send_cmd_reserved_powered() returned void while the other two
variants of pvr_kccb_send_cmd*() returned int.

The error is now propagated all the way to the DRM scheduler's run_job()
callback, which is the only user of pvr_kccb_send_cmd_reserved_powered()
outside of the other variants of pvr_kccb_send_cmd*().

Signed-off-by: Alessio Belle <alessio.belle@xxxxxxxxxx>
---
Signed-off-by: Alexandru Dadu <alexandru.dadu@xxxxxxxxxx>
---
drivers/gpu/drm/imagination/pvr_ccb.c | 33 +++++++++++++++++++++++++--------
drivers/gpu/drm/imagination/pvr_ccb.h | 6 +++---
drivers/gpu/drm/imagination/pvr_cccb.c | 12 ++++++++----
drivers/gpu/drm/imagination/pvr_cccb.h | 20 ++++++++++----------
drivers/gpu/drm/imagination/pvr_queue.c | 28 ++++++++++++++++------------
5 files changed, 62 insertions(+), 37 deletions(-)

diff --git a/drivers/gpu/drm/imagination/pvr_ccb.c b/drivers/gpu/drm/imagination/pvr_ccb.c
index 4accf18e2341..8182babd8ad8 100644
--- a/drivers/gpu/drm/imagination/pvr_ccb.c
+++ b/drivers/gpu/drm/imagination/pvr_ccb.c
@@ -257,8 +257,13 @@ pvr_kccb_used_slot_count_locked(struct pvr_device *pvr_dev)
* @pvr_dev: Device pointer.
* @cmd: Command to sent.
* @kccb_slot: Address to store the KCCB slot for this command. May be %NULL.
+ *
+ * Returns:
+ * * Zero on success,
+ * * -EIO if the device is lost, or
+ * * -EINVAL if a KCCB slot was not reserved or is not available.
*/
-void
+int
pvr_kccb_send_cmd_reserved_powered(struct pvr_device *pvr_dev,
struct rogue_fwif_kccb_cmd *cmd,
u32 *kccb_slot)
@@ -268,19 +273,25 @@ pvr_kccb_send_cmd_reserved_powered(struct pvr_device *pvr_dev,
struct rogue_fwif_ccb_ctl *ctrl = pvr_ccb->ctrl;
u32 old_write_offset;
u32 new_write_offset;
+ int err;

- WARN_ON(pvr_dev->lost);
+ if (pvr_dev->lost)
+ return -EIO;

mutex_lock(&pvr_ccb->lock);

- if (WARN_ON(!pvr_dev->kccb.reserved_count))
+ if (WARN_ON(!pvr_dev->kccb.reserved_count)) {
+ err = -EINVAL;
goto out_unlock;
+ }

old_write_offset = READ_ONCE(ctrl->write_offset);

/* We reserved the slot, we should have one available. */
- if (WARN_ON(!pvr_ccb_slot_available_locked(pvr_ccb, &new_write_offset)))
+ if (WARN_ON(!pvr_ccb_slot_available_locked(pvr_ccb, &new_write_offset))) {
+ err = -EINVAL;
goto out_unlock;
+ }

memcpy(&kccb[old_write_offset], cmd,
sizeof(struct rogue_fwif_kccb_cmd));
@@ -298,8 +309,14 @@ pvr_kccb_send_cmd_reserved_powered(struct pvr_device *pvr_dev,
pvr_fw_mts_schedule(pvr_dev,
PVR_FWIF_DM_GP & ~ROGUE_CR_MTS_SCHEDULE_DM_CLRMSK);

+ mutex_unlock(&pvr_ccb->lock);
+
+ return 0;
+
out_unlock:
mutex_unlock(&pvr_ccb->lock);
+
+ return err;
}

/**
@@ -365,8 +382,9 @@ static int pvr_kccb_reserve_slot_sync(struct pvr_device *pvr_dev)
* @kccb_slot: Address to store the KCCB slot for this command. May be %NULL.
*
* Returns:
- * * Zero on success, or
- * * -EBUSY if timeout while waiting for a free KCCB slot.
+ * * Zero on success,
+ * * Any error returned by pvr_kccb_reserve_slot_sync(), or
+ * * Any error returned by pvr_kccb_send_cmd_reserved_powered().
*/
int
pvr_kccb_send_cmd_powered(struct pvr_device *pvr_dev, struct rogue_fwif_kccb_cmd *cmd,
@@ -378,8 +396,7 @@ pvr_kccb_send_cmd_powered(struct pvr_device *pvr_dev, struct rogue_fwif_kccb_cmd
if (err)
return err;

- pvr_kccb_send_cmd_reserved_powered(pvr_dev, cmd, kccb_slot);
- return 0;
+ return pvr_kccb_send_cmd_reserved_powered(pvr_dev, cmd, kccb_slot);
}

/**
diff --git a/drivers/gpu/drm/imagination/pvr_ccb.h b/drivers/gpu/drm/imagination/pvr_ccb.h
index 4c8aef31eeb0..8b698206c68b 100644
--- a/drivers/gpu/drm/imagination/pvr_ccb.h
+++ b/drivers/gpu/drm/imagination/pvr_ccb.h
@@ -60,9 +60,9 @@ int pvr_kccb_send_cmd(struct pvr_device *pvr_dev,
int pvr_kccb_send_cmd_powered(struct pvr_device *pvr_dev,
struct rogue_fwif_kccb_cmd *cmd,
u32 *kccb_slot);
-void pvr_kccb_send_cmd_reserved_powered(struct pvr_device *pvr_dev,
- struct rogue_fwif_kccb_cmd *cmd,
- u32 *kccb_slot);
+int pvr_kccb_send_cmd_reserved_powered(struct pvr_device *pvr_dev,
+ struct rogue_fwif_kccb_cmd *cmd,
+ u32 *kccb_slot);
int pvr_kccb_wait_for_completion(struct pvr_device *pvr_dev, u32 slot_nr, u32 timeout,
u32 *rtn_out);
bool pvr_kccb_is_idle(struct pvr_device *pvr_dev);
diff --git a/drivers/gpu/drm/imagination/pvr_cccb.c b/drivers/gpu/drm/imagination/pvr_cccb.c
index 4fabab41bea7..da6e6d94e29f 100644
--- a/drivers/gpu/drm/imagination/pvr_cccb.c
+++ b/drivers/gpu/drm/imagination/pvr_cccb.c
@@ -220,8 +220,12 @@ static void fill_cmd_kick_data(struct pvr_cccb *cccb, u32 ctx_fw_addr,
* You must call pvr_kccb_reserve_slot() and wait for the returned fence to
* signal (if this function didn't return NULL) before calling
* pvr_cccb_send_kccb_kick().
+ *
+ * Returns:
+ * * Zero on success, or
+ * * Any error returned by pvr_kccb_send_cmd_reserved_powered().
*/
-void
+int
pvr_cccb_send_kccb_kick(struct pvr_device *pvr_dev,
struct pvr_cccb *pvr_cccb, u32 cctx_fw_addr,
struct pvr_hwrt_data *hwrt)
@@ -235,10 +239,10 @@ pvr_cccb_send_kccb_kick(struct pvr_device *pvr_dev,
/* Make sure the writes to the CCCB are flushed before sending the KICK. */
wmb();

- pvr_kccb_send_cmd_reserved_powered(pvr_dev, &cmd_kick, NULL);
+ return pvr_kccb_send_cmd_reserved_powered(pvr_dev, &cmd_kick, NULL);
}

-void
+int
pvr_cccb_send_kccb_combined_kick(struct pvr_device *pvr_dev,
struct pvr_cccb *geom_cccb,
struct pvr_cccb *frag_cccb,
@@ -263,5 +267,5 @@ pvr_cccb_send_kccb_combined_kick(struct pvr_device *pvr_dev,
/* Make sure the writes to the CCCB are flushed before sending the KICK. */
wmb();

- pvr_kccb_send_cmd_reserved_powered(pvr_dev, &cmd_kick, NULL);
+ return pvr_kccb_send_cmd_reserved_powered(pvr_dev, &cmd_kick, NULL);
}
diff --git a/drivers/gpu/drm/imagination/pvr_cccb.h b/drivers/gpu/drm/imagination/pvr_cccb.h
index 943fe8f2c963..a2155f732bf1 100644
--- a/drivers/gpu/drm/imagination/pvr_cccb.h
+++ b/drivers/gpu/drm/imagination/pvr_cccb.h
@@ -59,16 +59,16 @@ void pvr_cccb_fini(struct pvr_cccb *cccb);
void pvr_cccb_write_command_with_header(struct pvr_cccb *pvr_cccb,
u32 cmd_type, u32 cmd_size, void *cmd_data,
u32 ext_job_ref, u32 int_job_ref);
-void pvr_cccb_send_kccb_kick(struct pvr_device *pvr_dev,
- struct pvr_cccb *pvr_cccb, u32 cctx_fw_addr,
- struct pvr_hwrt_data *hwrt);
-void pvr_cccb_send_kccb_combined_kick(struct pvr_device *pvr_dev,
- struct pvr_cccb *geom_cccb,
- struct pvr_cccb *frag_cccb,
- u32 geom_ctx_fw_addr,
- u32 frag_ctx_fw_addr,
- struct pvr_hwrt_data *hwrt,
- bool frag_is_pr);
+int pvr_cccb_send_kccb_kick(struct pvr_device *pvr_dev,
+ struct pvr_cccb *pvr_cccb, u32 cctx_fw_addr,
+ struct pvr_hwrt_data *hwrt);
+int pvr_cccb_send_kccb_combined_kick(struct pvr_device *pvr_dev,
+ struct pvr_cccb *geom_cccb,
+ struct pvr_cccb *frag_cccb,
+ u32 geom_ctx_fw_addr,
+ u32 frag_ctx_fw_addr,
+ struct pvr_hwrt_data *hwrt,
+ bool frag_is_pr);
bool pvr_cccb_cmdseq_fits(struct pvr_cccb *pvr_cccb, size_t size);

/**
diff --git a/drivers/gpu/drm/imagination/pvr_queue.c b/drivers/gpu/drm/imagination/pvr_queue.c
index 54e88b4208d7..0f46bbfb9886 100644
--- a/drivers/gpu/drm/imagination/pvr_queue.c
+++ b/drivers/gpu/drm/imagination/pvr_queue.c
@@ -792,24 +792,28 @@ static struct dma_fence *pvr_queue_run_job(struct drm_sched_job *sched_job)

/* Submit the fragment job along the geometry job and send a combined kick. */
pvr_queue_submit_job_to_cccb(frag_job);
- pvr_cccb_send_kccb_combined_kick(pvr_dev,
- &geom_queue->cccb, &frag_queue->cccb,
- pvr_context_get_fw_addr(geom_job->ctx) +
- geom_queue->ctx_offset,
- pvr_context_get_fw_addr(frag_job->ctx) +
- frag_queue->ctx_offset,
- job->hwrt,
- frag_job->fw_ccb_cmd_type ==
- ROGUE_FWIF_CCB_CMD_TYPE_FRAG_PR);
+ err = pvr_cccb_send_kccb_combined_kick(pvr_dev,
+ &geom_queue->cccb, &frag_queue->cccb,
+ pvr_context_get_fw_addr(geom_job->ctx) +
+ geom_queue->ctx_offset,
+ pvr_context_get_fw_addr(frag_job->ctx) +
+ frag_queue->ctx_offset,
+ job->hwrt,
+ frag_job->fw_ccb_cmd_type ==
+ ROGUE_FWIF_CCB_CMD_TYPE_FRAG_PR);
} else {
struct pvr_queue *queue = container_of(job->base.sched,
struct pvr_queue, scheduler);

- pvr_cccb_send_kccb_kick(pvr_dev, &queue->cccb,
- pvr_context_get_fw_addr(job->ctx) + queue->ctx_offset,
- job->hwrt);
+ err = pvr_cccb_send_kccb_kick(pvr_dev, &queue->cccb,
+ pvr_context_get_fw_addr(job->ctx) +
+ queue->ctx_offset,
+ job->hwrt);
}

+ if (WARN_ON(err))
+ return ERR_PTR(err);
+
return dma_fence_get(job->done_fence);
}


---
base-commit: e55fead22ff9ee047ab9f1903860c4b43043514e
change-id: 20260810-b4-upstream-propagate-all-errors-from-kccb-cmd-submission-code-0dae4f05fcb5

Best regards,
--
Alexandru Dadu <alexandru.dadu@xxxxxxxxxx>