diff --git a/drivers/infiniband/hw/mlx5/main.c b/drivers/infiniband/hw/mlx5/main.c
index 39d54e285ae9..27255f68b2fb 100644
--- a/drivers/infiniband/hw/mlx5/main.c
+++ b/drivers/infiniband/hw/mlx5/main.c
@@ -1811,7 +1811,7 @@ static int mlx5_ib_alloc_ucontext(struct ib_ucontext *uctx,
 		return -EINVAL;

 	resp.qp_tab_size = 1 << MLX5_CAP_GEN(dev->mdev, log_max_qp);
-	if (mlx5_core_is_pf(dev->mdev) && MLX5_CAP_GEN(dev->mdev, bf))
+	if (dev->wc_support)
 		resp.bf_reg_size = 1 << MLX5_CAP_GEN(dev->mdev, log_bf_reg_size);
 	resp.cache_line_size = cache_line_size();
 	resp.max_sq_desc_sz = MLX5_CAP_GEN(dev->mdev, max_wqe_sz_sq);
@@ -6272,6 +6272,7 @@ static const struct ib_device_ops mlx5_ib_dev_ops = {
 	.disassociate_ucontext = mlx5_ib_disassociate_ucontext,
 	.drain_rq = mlx5_ib_drain_rq,
 	.drain_sq = mlx5_ib_drain_sq,
+	.enable_driver = mlx5_ib_enable_driver,
 	.fill_res_entry = mlx5_ib_fill_res_entry,
 	.fill_stat_entry = mlx5_ib_fill_stat_entry,
 	.get_dev_fw_str = get_dev_fw_str,
@@ -6715,6 +6716,18 @@ static void mlx5_ib_stage_devx_cleanup(struct mlx5_ib_dev *dev)
 	}
 }

+int mlx5_ib_enable_driver(struct ib_device *dev)
+{
+	struct mlx5_ib_dev *mdev = to_mdev(dev);
+	int ret;
+
+	ret = mlx5_ib_test_wc(mdev);
+	mlx5_ib_dbg(mdev, "Write-Combining %s",
+		    mdev->wc_support ? "supported" : "not supported");
+
+	return ret;
+}
+
 void __mlx5_ib_remove(struct mlx5_ib_dev *dev,
 		      const struct mlx5_ib_profile *profile,
 		      int stage)
diff --git a/drivers/infiniband/hw/mlx5/mem.c b/drivers/infiniband/hw/mlx5/mem.c
index b5aece786b36..8a436fdc5d3a 100644
--- a/drivers/infiniband/hw/mlx5/mem.c
+++ b/drivers/infiniband/hw/mlx5/mem.c
@@ -34,6 +34,7 @@
 #include <rdma/ib_umem.h>
 #include <rdma/ib_umem_odp.h>
 #include "mlx5_ib.h"
+#include <linux/jiffies.h>

 /* @umem: umem object to scan
  * @addr: ib virtual address requested by the user
@@ -216,3 +217,202 @@ int mlx5_ib_get_buf_offset(u64 addr, int page_shift, u32 *offset)
 	*offset = buf_off >> ilog2(off_size);
 	return 0;
 }
+
+#define WR_ID_BF 0xBF
+#define WR_ID_END 0xBAD
+#define TEST_WC_NUM_WQES 255
+#define TEST_WC_POLLING_MAX_TIME_JIFFIES msecs_to_jiffies(100)
+static int post_send_nop(struct mlx5_ib_dev *dev, struct ib_qp *ibqp, u64 wr_id,
+			 bool signaled)
+{
+	struct mlx5_ib_qp *qp = to_mqp(ibqp);
+	struct mlx5_wqe_ctrl_seg *ctrl;
+	struct mlx5_bf *bf = &qp->bf;
+	__be32 mmio_wqe[16] = {};
+	unsigned int idx;
+	int i;
+
+	if (unlikely(dev->mdev->state == MLX5_DEVICE_STATE_INTERNAL_ERROR))
+		return -EIO;
+
+	/* This could be done without taking the lock as the test is running in
+	 * init process. Using spin lock anyway to maintain code completness.
+	 */
+	spin_lock(&qp->sq.lock);
+
+	idx = qp->sq.cur_post & (qp->sq.wqe_cnt - 1);
+	ctrl = mlx5_frag_buf_get_wqe(&qp->sq.fbc, idx);
+
+	memset(ctrl, 0, sizeof(struct mlx5_wqe_ctrl_seg));
+	ctrl->fm_ce_se = signaled ? MLX5_WQE_CTRL_CQ_UPDATE : 0;
+	ctrl->opmod_idx_opcode =
+		cpu_to_be32(((u32)(qp->sq.cur_post) << 8) | MLX5_OPCODE_NOP);
+	ctrl->qpn_ds = cpu_to_be32((sizeof(struct mlx5_wqe_ctrl_seg) / 16) |
+				   (qp->trans_qp.base.mqp.qpn << 8));
+
+	qp->sq.wrid[idx] = wr_id;
+	qp->sq.w_list[idx].opcode = MLX5_OPCODE_NOP;
+	qp->sq.wqe_head[idx] = qp->sq.head + 1;
+	qp->sq.cur_post += MLX5_SEND_WQE_BB;
+	qp->sq.w_list[idx].next = qp->sq.cur_post;
+	qp->sq.head++;
+
+	memcpy(mmio_wqe, ctrl, sizeof(*ctrl));
+	((struct mlx5_wqe_ctrl_seg *)&mmio_wqe)->fm_ce_se |=
+		MLX5_WQE_CTRL_CQ_UPDATE;
+
+	/* Make sure that descriptors are written before
+	 * updating doorbell record and ringing the doorbell
+	 */
+	wmb();
+
+	qp->db.db[MLX5_SND_DBR] = cpu_to_be32(qp->sq.cur_post);
+
+	/* Make sure doorbell record is visible to the HCA before
+	 * we hit doorbell
+	 */
+	wmb();
+	for (i = 0; i < 8; i++)
+		mlx5_write64(&mmio_wqe[i * 2],
+			     bf->bfreg->map + bf->offset + i * 8);
+
+	bf->offset ^= bf->buf_size;
+
+	spin_unlock(&qp->sq.lock);
+
+	return 0;
+}
+
+static int test_wc_poll_cq_result(struct mlx5_ib_dev *dev, struct ib_cq *cq)
+{
+	int ret;
+	struct ib_wc wc = {};
+	unsigned long end = jiffies + TEST_WC_POLLING_MAX_TIME_JIFFIES;
+
+	do {
+		ret = ib_poll_cq(cq, 1, &wc);
+		if (ret < 0 || wc.status)
+			return ret < 0 ? ret : -EINVAL;
+		if (ret)
+			break;
+	} while (!time_after(jiffies, end));
+
+	if (!ret)
+		return -ETIMEDOUT;
+
+	if (wc.wr_id != WR_ID_BF)
+		ret = 0;
+
+	return ret;
+}
+
+static int test_wc_do_send(struct mlx5_ib_dev *dev, struct ib_qp *qp)
+{
+	int err, i;
+
+	for (i = 0; i < TEST_WC_NUM_WQES; i++) {
+		err = post_send_nop(dev, qp, WR_ID_BF, false);
+		if (err)
+			return err;
+	}
+
+	return post_send_nop(dev, qp, WR_ID_END, true);
+}
+
+int mlx5_ib_test_wc(struct mlx5_ib_dev *dev)
+{
+	struct ib_cq_init_attr cq_attr = { .cqe = TEST_WC_NUM_WQES + 1 };
+	int port_type_cap = MLX5_CAP_GEN(dev->mdev, port_type);
+	struct ib_qp_init_attr qp_init_attr = {
+		.cap = { .max_send_wr = TEST_WC_NUM_WQES },
+		.qp_type = IB_QPT_UD,
+		.sq_sig_type = IB_SIGNAL_REQ_WR,
+		.create_flags = MLX5_IB_QP_CREATE_WC_TEST,
+	};
+	struct ib_qp_attr qp_attr = { .port_num = 1 };
+	struct ib_device *ibdev = &dev->ib_dev;
+	struct ib_qp *qp;
+	struct ib_cq *cq;
+	struct ib_pd *pd;
+	int ret;
+
+	if (!MLX5_CAP_GEN(dev->mdev, bf))
+		return 0;
+
+	if (!dev->mdev->roce.roce_en &&
+	    port_type_cap == MLX5_CAP_PORT_TYPE_ETH) {
+		if (mlx5_core_is_pf(dev->mdev))
+			dev->wc_support = true;
+		return 0;
+	}
+
+	ret = mlx5_alloc_bfreg(dev->mdev, &dev->wc_bfreg, true, false);
+	if (ret)
+		goto print_err;
+
+	if (!dev->wc_bfreg.wc)
+		goto out1;
+
+	pd = ib_alloc_pd(ibdev, 0);
+	if (IS_ERR(pd)) {
+		ret = PTR_ERR(pd);
+		goto out1;
+	}
+
+	cq = ib_create_cq(ibdev, NULL, NULL, NULL, &cq_attr);
+	if (IS_ERR(cq)) {
+		ret = PTR_ERR(cq);
+		goto out2;
+	}
+
+	qp_init_attr.recv_cq = cq;
+	qp_init_attr.send_cq = cq;
+	qp = ib_create_qp(pd, &qp_init_attr);
+	if (IS_ERR(qp)) {
+		ret = PTR_ERR(qp);
+		goto out3;
+	}
+
+	qp_attr.qp_state = IB_QPS_INIT;
+	ret = ib_modify_qp(qp, &qp_attr,
+			   IB_QP_STATE | IB_QP_PORT | IB_QP_PKEY_INDEX |
+				   IB_QP_QKEY);
+	if (ret)
+		goto out4;
+
+	qp_attr.qp_state = IB_QPS_RTR;
+	ret = ib_modify_qp(qp, &qp_attr, IB_QP_STATE);
+	if (ret)
+		goto out4;
+
+	qp_attr.qp_state = IB_QPS_RTS;
+	ret = ib_modify_qp(qp, &qp_attr, IB_QP_STATE | IB_QP_SQ_PSN);
+	if (ret)
+		goto out4;
+
+	ret = test_wc_do_send(dev, qp);
+	if (ret < 0)
+		goto out4;
+
+	ret = test_wc_poll_cq_result(dev, cq);
+	if (ret > 0) {
+		dev->wc_support = true;
+		ret = 0;
+	}
+
+out4:
+	ib_destroy_qp(qp);
+out3:
+	ib_destroy_cq(cq);
+out2:
+	ib_dealloc_pd(pd);
+out1:
+	mlx5_free_bfreg(dev->mdev, &dev->wc_bfreg);
+print_err:
+	if (ret)
+		mlx5_ib_err(
+			dev,
+			"Error %d while trying to test write-combining support\n",
+			ret);
+	return ret;
+}
diff --git a/drivers/infiniband/hw/mlx5/mlx5_ib.h b/drivers/infiniband/hw/mlx5/mlx5_ib.h
index 27980295aee8..d5c80aa9efb1 100644
--- a/drivers/infiniband/hw/mlx5/mlx5_ib.h
+++ b/drivers/infiniband/hw/mlx5/mlx5_ib.h
@@ -248,6 +248,7 @@ struct mlx5_ib_flow_db {
  * rely on the range reserved for that use in the ib_qp_create_flags enum.
  */
 #define MLX5_IB_QP_CREATE_SQPN_QP1	IB_QP_CREATE_RESERVED_START
+#define MLX5_IB_QP_CREATE_WC_TEST	(IB_QP_CREATE_RESERVED_START << 1)

 struct wr_list {
 	u16	opcode;
@@ -962,6 +963,7 @@ struct mlx5_ib_dev {
 	u8				fill_delay:1;
 	u8				is_rep:1;
 	u8				lag_active:1;
+	u8				wc_support:1;
 	struct umr_common		umrc;
 	/* sync used page count stats
 	 */
@@ -987,6 +989,7 @@ struct mlx5_ib_dev {
 	/* Array with num_ports elements */
 	struct mlx5_ib_port	*port;
 	struct mlx5_sq_bfreg	bfreg;
+	struct mlx5_sq_bfreg	wc_bfreg;
 	struct mlx5_sq_bfreg	fp_bfreg;
 	struct mlx5_ib_delay_drop	delay_drop;
 	const struct mlx5_ib_profile	*profile;
@@ -1496,4 +1499,7 @@ static inline bool mlx5_ib_can_use_umr(struct mlx5_ib_dev *dev,

 	return true;
 }
+
+int mlx5_ib_enable_driver(struct ib_device *dev);
+int mlx5_ib_test_wc(struct mlx5_ib_dev *dev);
 #endif /* MLX5_IB_H */
diff --git a/drivers/infiniband/hw/mlx5/qp.c b/drivers/infiniband/hw/mlx5/qp.c
index bb3f432e2fb6..c831b455ffa8 100644
--- a/drivers/infiniband/hw/mlx5/qp.c
+++ b/drivers/infiniband/hw/mlx5/qp.c
@@ -1041,11 +1041,14 @@ static int create_kernel_qp(struct mlx5_ib_dev *dev,
 					IB_QP_CREATE_BLOCK_MULTICAST_LOOPBACK |
 					IB_QP_CREATE_IPOIB_UD_LSO |
 					IB_QP_CREATE_NETIF_QP |
-					MLX5_IB_QP_CREATE_SQPN_QP1))
+					MLX5_IB_QP_CREATE_SQPN_QP1 |
+					MLX5_IB_QP_CREATE_WC_TEST))
 		return -EINVAL;

 	if (init_attr->qp_type == MLX5_IB_QPT_REG_UMR)
 		qp->bf.bfreg = &dev->fp_bfreg;
+	else if (init_attr->create_flags & MLX5_IB_QP_CREATE_WC_TEST)
+		qp->bf.bfreg = &dev->wc_bfreg;
 	else
 		qp->bf.bfreg = &dev->bfreg;

@@ -5328,7 +5331,6 @@ static int _mlx5_ib_post_send(struct ib_qp *ibqp, const struct ib_send_wr *wr,
 		 * we hit doorbell */
 		wmb();

-		/* currently we support only regular doorbells */
 		mlx5_write64((__be32 *)ctrl, bf->bfreg->map + bf->offset);
 		/* Make sure doorbells don't leak out of SQ spinlock
 		 * and reach the HCA out of order.
