octeontx2-pf: QOS: Perform cache sync on send queue teardown

QOS is designed to create a new send queue whenever  a class
is created, ensuring proper shaping and scheduling. However,
when multiple send queues are created and deleted in a loop,
SMMU errors are observed.

This patch addresses the issue by performing an data cache sync
during the teardown of QOS send queues.

Fixes: ab6dddd ("octeontx2-pf: qos send queues management")
Signed-off-by: Hariprasad Kelam <hkelam@marvell.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250522094742.1498295-1-hkelam@marvell.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Author: Hariprasad Kelam

drivers/net/ethernet/marvell/octeontx2/nic/qos_sq.c

@@ -256,6 +256,26 @@ int otx2_qos_enable_sq(struct otx2_nic *pfvf, int qidx)
 	return err;
 }
 
+static int otx2_qos_nix_npa_ndc_sync(struct otx2_nic *pfvf)
+{
+	struct ndc_sync_op *req;
+	int rc;
+
+	mutex_lock(&pfvf->mbox.lock);
+
+	req = otx2_mbox_alloc_msg_ndc_sync_op(&pfvf->mbox);
+	if (!req) {
+		mutex_unlock(&pfvf->mbox.lock);
+		return -ENOMEM;
+	}
+
+	req->nix_lf_tx_sync = true;
+	req->npa_lf_sync = true;
+	rc = otx2_sync_mbox_msg(&pfvf->mbox);
+	mutex_unlock(&pfvf->mbox.lock);
+	return rc;
+}
+
 void otx2_qos_disable_sq(struct otx2_nic *pfvf, int qidx)
 {
 	struct otx2_qset *qset = &pfvf->qset;
@@ -285,6 +305,8 @@ void otx2_qos_disable_sq(struct otx2_nic *pfvf, int qidx)
 
 	otx2_qos_sqb_flush(pfvf, sq_idx);
 	otx2_smq_flush(pfvf, otx2_get_smq_idx(pfvf, sq_idx));
+	/* NIX/NPA NDC sync */
+	otx2_qos_nix_npa_ndc_sync(pfvf);
 	otx2_cleanup_tx_cqes(pfvf, cq);
 
 	mutex_lock(&pfvf->mbox.lock);