crypto: hisilicon/qm - implement for querying hardware tasks status.

This patch adds a function hisi_qm_is_q_updated to
check if the task is ready in hardware queue when
user polls an UACCE queue.This prevents users from
repeatedly querying whether the accelerator has
completed tasks, which wastes CPU resources.

Signed-off-by: Wenkai Lin <linwenkai6@hisilicon.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/hisilicon/qm.c

@@ -2926,6 +2926,23 @@ static void hisi_qm_uacce_stop_queue(struct uacce_queue *q)
 	hisi_qm_stop_qp(q->priv);
 }
 
+static int hisi_qm_is_q_updated(struct uacce_queue *q)
+{
+	struct hisi_qp *qp = q->priv;
+	struct qm_cqe *cqe = qp->cqe + qp->qp_status.cq_head;
+	int updated = 0;
+
+	while (QM_CQE_PHASE(cqe) == qp->qp_status.cqc_phase) {
+		/* make sure to read data from memory */
+		dma_rmb();
+		qm_cq_head_update(qp);
+		cqe = qp->cqe + qp->qp_status.cq_head;
+		updated = 1;
+	}
+
+	return updated;
+}
+
 static void qm_set_sqctype(struct uacce_queue *q, u16 type)
 {
 	struct hisi_qm *qm = q->uacce->priv;
@@ -2971,6 +2988,7 @@ static const struct uacce_ops uacce_qm_ops = {
 	.stop_queue = hisi_qm_uacce_stop_queue,
 	.mmap = hisi_qm_uacce_mmap,
 	.ioctl = hisi_qm_uacce_ioctl,
+	.is_q_updated = hisi_qm_is_q_updated,
 };
 
 static int qm_alloc_uacce(struct hisi_qm *qm)