diff --git a/drivers/infiniband/hw/erdma/erdma_cmdq.c b/drivers/infiniband/hw/erdma/erdma_cmdq.c
new file mode 100644
index 000000000000..8bc3c90cdf7a
--- /dev/null
+++ b/drivers/infiniband/hw/erdma/erdma_cmdq.c
@@ -0,0 +1,497 @@
+// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
+
+/* Authors: Cheng Xu <chengyou@linux.alibaba.com> */
+/*          Kai Shen <kaishen@linux.alibaba.com> */
+/* Copyright (c) 2020-2022, Alibaba Group. */
+
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/pci.h>
+
+#include "erdma.h"
+#include "erdma_hw.h"
+#include "erdma_verbs.h"
+
+static void arm_cmdq_cq(struct erdma_cmdq *cmdq)
+{
+	struct erdma_dev *dev = container_of(cmdq, struct erdma_dev, cmdq);
+	u64 db_data = FIELD_PREP(ERDMA_CQDB_CI_MASK, cmdq->cq.ci) |
+		      FIELD_PREP(ERDMA_CQDB_ARM_MASK, 1) |
+		      FIELD_PREP(ERDMA_CQDB_CMDSN_MASK, cmdq->cq.cmdsn) |
+		      FIELD_PREP(ERDMA_CQDB_IDX_MASK, cmdq->cq.cmdsn);
+
+	*cmdq->cq.db_record = db_data;
+	writeq(db_data, dev->func_bar + ERDMA_CMDQ_CQDB_REG);
+
+	atomic64_inc(&cmdq->cq.armed_num);
+}
+
+static void kick_cmdq_db(struct erdma_cmdq *cmdq)
+{
+	struct erdma_dev *dev = container_of(cmdq, struct erdma_dev, cmdq);
+	u64 db_data = FIELD_PREP(ERDMA_CMD_HDR_WQEBB_INDEX_MASK, cmdq->sq.pi);
+
+	*cmdq->sq.db_record = db_data;
+	writeq(db_data, dev->func_bar + ERDMA_CMDQ_SQDB_REG);
+}
+
+static struct erdma_comp_wait *get_comp_wait(struct erdma_cmdq *cmdq)
+{
+	int comp_idx;
+
+	spin_lock(&cmdq->lock);
+	comp_idx = find_first_zero_bit(cmdq->comp_wait_bitmap,
+				       cmdq->max_outstandings);
+	if (comp_idx == cmdq->max_outstandings) {
+		spin_unlock(&cmdq->lock);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	set_bit(comp_idx, cmdq->comp_wait_bitmap);
+	spin_unlock(&cmdq->lock);
+
+	return &cmdq->wait_pool[comp_idx];
+}
+
+static void put_comp_wait(struct erdma_cmdq *cmdq,
+			  struct erdma_comp_wait *comp_wait)
+{
+	int used;
+
+	cmdq->wait_pool[comp_wait->ctx_id].cmd_status = ERDMA_CMD_STATUS_INIT;
+	spin_lock(&cmdq->lock);
+	used = test_and_clear_bit(comp_wait->ctx_id, cmdq->comp_wait_bitmap);
+	spin_unlock(&cmdq->lock);
+
+	WARN_ON(!used);
+}
+
+static int erdma_cmdq_wait_res_init(struct erdma_dev *dev,
+				    struct erdma_cmdq *cmdq)
+{
+	int i;
+
+	cmdq->wait_pool =
+		devm_kcalloc(&dev->pdev->dev, cmdq->max_outstandings,
+			     sizeof(struct erdma_comp_wait), GFP_KERNEL);
+	if (!cmdq->wait_pool)
+		return -ENOMEM;
+
+	spin_lock_init(&cmdq->lock);
+	cmdq->comp_wait_bitmap =
+		devm_kcalloc(&dev->pdev->dev,
+			     BITS_TO_LONGS(cmdq->max_outstandings),
+			     sizeof(unsigned long), GFP_KERNEL);
+	if (!cmdq->comp_wait_bitmap) {
+		devm_kfree(&dev->pdev->dev, cmdq->wait_pool);
+		return -ENOMEM;
+	}
+
+	for (i = 0; i < cmdq->max_outstandings; i++) {
+		init_completion(&cmdq->wait_pool[i].wait_event);
+		cmdq->wait_pool[i].ctx_id = i;
+	}
+
+	return 0;
+}
+
+static int erdma_cmdq_sq_init(struct erdma_dev *dev)
+{
+	struct erdma_cmdq *cmdq = &dev->cmdq;
+	struct erdma_cmdq_sq *sq = &cmdq->sq;
+	u32 buf_size;
+
+	sq->wqebb_cnt = SQEBB_COUNT(ERDMA_CMDQ_SQE_SIZE);
+	sq->depth = cmdq->max_outstandings * sq->wqebb_cnt;
+
+	buf_size = sq->depth << SQEBB_SHIFT;
+
+	sq->qbuf =
+		dma_alloc_coherent(&dev->pdev->dev, WARPPED_BUFSIZE(buf_size),
+				   &sq->qbuf_dma_addr, GFP_KERNEL);
+	if (!sq->qbuf)
+		return -ENOMEM;
+
+	sq->db_record = (u64 *)(sq->qbuf + buf_size);
+
+	spin_lock_init(&sq->lock);
+
+	erdma_reg_write32(dev, ERDMA_REGS_CMDQ_SQ_ADDR_H_REG,
+			  upper_32_bits(sq->qbuf_dma_addr));
+	erdma_reg_write32(dev, ERDMA_REGS_CMDQ_SQ_ADDR_L_REG,
+			  lower_32_bits(sq->qbuf_dma_addr));
+	erdma_reg_write32(dev, ERDMA_REGS_CMDQ_DEPTH_REG, sq->depth);
+	erdma_reg_write64(dev, ERDMA_CMDQ_SQ_DB_HOST_ADDR_REG,
+			  sq->qbuf_dma_addr + buf_size);
+
+	return 0;
+}
+
+static int erdma_cmdq_cq_init(struct erdma_dev *dev)
+{
+	struct erdma_cmdq *cmdq = &dev->cmdq;
+	struct erdma_cmdq_cq *cq = &cmdq->cq;
+	u32 buf_size;
+
+	cq->depth = cmdq->sq.depth;
+	buf_size = cq->depth << CQE_SHIFT;
+
+	cq->qbuf =
+		dma_alloc_coherent(&dev->pdev->dev, WARPPED_BUFSIZE(buf_size),
+				   &cq->qbuf_dma_addr, GFP_KERNEL | __GFP_ZERO);
+	if (!cq->qbuf)
+		return -ENOMEM;
+
+	spin_lock_init(&cq->lock);
+
+	cq->db_record = (u64 *)(cq->qbuf + buf_size);
+
+	atomic64_set(&cq->armed_num, 0);
+
+	erdma_reg_write32(dev, ERDMA_REGS_CMDQ_CQ_ADDR_H_REG,
+			  upper_32_bits(cq->qbuf_dma_addr));
+	erdma_reg_write32(dev, ERDMA_REGS_CMDQ_CQ_ADDR_L_REG,
+			  lower_32_bits(cq->qbuf_dma_addr));
+	erdma_reg_write64(dev, ERDMA_CMDQ_CQ_DB_HOST_ADDR_REG,
+			  cq->qbuf_dma_addr + buf_size);
+
+	return 0;
+}
+
+static int erdma_cmdq_eq_init(struct erdma_dev *dev)
+{
+	struct erdma_cmdq *cmdq = &dev->cmdq;
+	struct erdma_eq *eq = &cmdq->eq;
+	u32 buf_size;
+
+	eq->depth = cmdq->max_outstandings;
+	buf_size = eq->depth << EQE_SHIFT;
+
+	eq->qbuf =
+		dma_alloc_coherent(&dev->pdev->dev, WARPPED_BUFSIZE(buf_size),
+				   &eq->qbuf_dma_addr, GFP_KERNEL | __GFP_ZERO);
+	if (!eq->qbuf)
+		return -ENOMEM;
+
+	spin_lock_init(&eq->lock);
+	atomic64_set(&eq->event_num, 0);
+
+	eq->db_addr =
+		(u64 __iomem *)(dev->func_bar + ERDMA_REGS_CEQ_DB_BASE_REG);
+	eq->db_record = (u64 *)(eq->qbuf + buf_size);
+
+	erdma_reg_write32(dev, ERDMA_REGS_CMDQ_EQ_ADDR_H_REG,
+			  upper_32_bits(eq->qbuf_dma_addr));
+	erdma_reg_write32(dev, ERDMA_REGS_CMDQ_EQ_ADDR_L_REG,
+			  lower_32_bits(eq->qbuf_dma_addr));
+	erdma_reg_write32(dev, ERDMA_REGS_CMDQ_EQ_DEPTH_REG, eq->depth);
+	erdma_reg_write64(dev, ERDMA_CMDQ_EQ_DB_HOST_ADDR_REG,
+			  eq->qbuf_dma_addr + buf_size);
+
+	return 0;
+}
+
+int erdma_cmdq_init(struct erdma_dev *dev)
+{
+	int err, i;
+	struct erdma_cmdq *cmdq = &dev->cmdq;
+	u32 status, ctrl;
+
+	cmdq->max_outstandings = ERDMA_CMDQ_MAX_OUTSTANDING;
+	cmdq->use_event = false;
+
+	sema_init(&cmdq->credits, cmdq->max_outstandings);
+
+	err = erdma_cmdq_wait_res_init(dev, cmdq);
+	if (err)
+		return err;
+
+	err = erdma_cmdq_sq_init(dev);
+	if (err)
+		return err;
+
+	err = erdma_cmdq_cq_init(dev);
+	if (err)
+		goto err_destroy_sq;
+
+	err = erdma_cmdq_eq_init(dev);
+	if (err)
+		goto err_destroy_cq;
+
+	ctrl = FIELD_PREP(ERDMA_REG_DEV_CTRL_INIT_MASK, 1);
+	erdma_reg_write32(dev, ERDMA_REGS_DEV_CTRL_REG, ctrl);
+
+	for (i = 0; i < ERDMA_WAIT_DEV_DONE_CNT; i++) {
+		status =
+			erdma_reg_read32_filed(dev, ERDMA_REGS_DEV_ST_REG,
+					       ERDMA_REG_DEV_ST_INIT_DONE_MASK);
+		if (status)
+			break;
+
+		msleep(ERDMA_REG_ACCESS_WAIT_MS);
+	}
+
+	if (i == ERDMA_WAIT_DEV_DONE_CNT) {
+		dev_err(&dev->pdev->dev, "wait init done failed.\n");
+		err = -ETIMEDOUT;
+		goto err_destroy_eq;
+	}
+
+	set_bit(ERDMA_CMDQ_STATE_OK_BIT, &cmdq->state);
+
+	return 0;
+
+err_destroy_eq:
+	dma_free_coherent(&dev->pdev->dev,
+			  (cmdq->eq.depth << EQE_SHIFT) +
+				  ERDMA_EXTRA_BUFFER_SIZE,
+			  cmdq->eq.qbuf, cmdq->eq.qbuf_dma_addr);
+
+err_destroy_cq:
+	dma_free_coherent(&dev->pdev->dev,
+			  (cmdq->cq.depth << CQE_SHIFT) +
+				  ERDMA_EXTRA_BUFFER_SIZE,
+			  cmdq->cq.qbuf, cmdq->cq.qbuf_dma_addr);
+
+err_destroy_sq:
+	dma_free_coherent(&dev->pdev->dev,
+			  (cmdq->sq.depth << SQEBB_SHIFT) +
+				  ERDMA_EXTRA_BUFFER_SIZE,
+			  cmdq->sq.qbuf, cmdq->sq.qbuf_dma_addr);
+
+	return err;
+}
+
+void erdma_finish_cmdq_init(struct erdma_dev *dev)
+{
+	/* after device init successfully, change cmdq to event mode. */
+	dev->cmdq.use_event = true;
+	arm_cmdq_cq(&dev->cmdq);
+}
+
+void erdma_cmdq_destroy(struct erdma_dev *dev)
+{
+	struct erdma_cmdq *cmdq = &dev->cmdq;
+
+	clear_bit(ERDMA_CMDQ_STATE_OK_BIT, &cmdq->state);
+
+	dma_free_coherent(&dev->pdev->dev,
+			  (cmdq->eq.depth << EQE_SHIFT) +
+				  ERDMA_EXTRA_BUFFER_SIZE,
+			  cmdq->eq.qbuf, cmdq->eq.qbuf_dma_addr);
+	dma_free_coherent(&dev->pdev->dev,
+			  (cmdq->sq.depth << SQEBB_SHIFT) +
+				  ERDMA_EXTRA_BUFFER_SIZE,
+			  cmdq->sq.qbuf, cmdq->sq.qbuf_dma_addr);
+	dma_free_coherent(&dev->pdev->dev,
+			  (cmdq->cq.depth << CQE_SHIFT) +
+				  ERDMA_EXTRA_BUFFER_SIZE,
+			  cmdq->cq.qbuf, cmdq->cq.qbuf_dma_addr);
+}
+
+static void *get_next_valid_cmdq_cqe(struct erdma_cmdq *cmdq)
+{
+	__be32 *cqe = get_queue_entry(cmdq->cq.qbuf, cmdq->cq.ci,
+				      cmdq->cq.depth, CQE_SHIFT);
+	u32 owner = FIELD_GET(ERDMA_CQE_HDR_OWNER_MASK,
+			      __be32_to_cpu(READ_ONCE(*cqe)));
+
+	return owner ^ !!(cmdq->cq.ci & cmdq->cq.depth) ? cqe : NULL;
+}
+
+static void push_cmdq_sqe(struct erdma_cmdq *cmdq, u64 *req, size_t req_len,
+			  struct erdma_comp_wait *comp_wait)
+{
+	__le64 *wqe;
+	u64 hdr = *req;
+
+	comp_wait->cmd_status = ERDMA_CMD_STATUS_ISSUED;
+	reinit_completion(&comp_wait->wait_event);
+	comp_wait->sq_pi = cmdq->sq.pi;
+
+	wqe = get_queue_entry(cmdq->sq.qbuf, cmdq->sq.pi, cmdq->sq.depth,
+			      SQEBB_SHIFT);
+	memcpy(wqe, req, req_len);
+
+	cmdq->sq.pi += cmdq->sq.wqebb_cnt;
+	hdr |= FIELD_PREP(ERDMA_CMD_HDR_WQEBB_INDEX_MASK, cmdq->sq.pi) |
+	       FIELD_PREP(ERDMA_CMD_HDR_CONTEXT_COOKIE_MASK,
+			  comp_wait->ctx_id) |
+	       FIELD_PREP(ERDMA_CMD_HDR_WQEBB_CNT_MASK, cmdq->sq.wqebb_cnt - 1);
+	*wqe = cpu_to_le64(hdr);
+
+	kick_cmdq_db(cmdq);
+}
+
+static int erdma_poll_single_cmd_completion(struct erdma_cmdq *cmdq)
+{
+	struct erdma_comp_wait *comp_wait;
+	u32 hdr0, sqe_idx;
+	__be32 *cqe;
+	u16 ctx_id;
+	u64 *sqe;
+	int i;
+
+	cqe = get_next_valid_cmdq_cqe(cmdq);
+	if (!cqe)
+		return -EAGAIN;
+
+	cmdq->cq.ci++;
+
+	dma_rmb();
+	hdr0 = __be32_to_cpu(*cqe);
+	sqe_idx = __be32_to_cpu(*(cqe + 1));
+
+	sqe = get_queue_entry(cmdq->sq.qbuf, sqe_idx, cmdq->sq.depth,
+			      SQEBB_SHIFT);
+	ctx_id = FIELD_GET(ERDMA_CMD_HDR_CONTEXT_COOKIE_MASK, *sqe);
+	comp_wait = &cmdq->wait_pool[ctx_id];
+	if (comp_wait->cmd_status != ERDMA_CMD_STATUS_ISSUED)
+		return -EIO;
+
+	comp_wait->cmd_status = ERDMA_CMD_STATUS_FINISHED;
+	comp_wait->comp_status = FIELD_GET(ERDMA_CQE_HDR_SYNDROME_MASK, hdr0);
+	cmdq->sq.ci += cmdq->sq.wqebb_cnt;
+
+	for (i = 0; i < 4; i++)
+		comp_wait->comp_data[i] = __be32_to_cpu(*(cqe + 2 + i));
+
+	if (cmdq->use_event)
+		complete(&comp_wait->wait_event);
+
+	return 0;
+}
+
+static void erdma_polling_cmd_completions(struct erdma_cmdq *cmdq)
+{
+	unsigned long flags;
+	u16 comp_num;
+
+	spin_lock_irqsave(&cmdq->cq.lock, flags);
+
+	/* We must have less than # of max_outstandings
+	 * completions at one time.
+	 */
+	for (comp_num = 0; comp_num < cmdq->max_outstandings; comp_num++)
+		if (erdma_poll_single_cmd_completion(cmdq))
+			break;
+
+	if (comp_num && cmdq->use_event)
+		arm_cmdq_cq(cmdq);
+
+	spin_unlock_irqrestore(&cmdq->cq.lock, flags);
+}
+
+void erdma_cmdq_completion_handler(struct erdma_cmdq *cmdq)
+{
+	int got_event = 0;
+
+	if (!test_bit(ERDMA_CMDQ_STATE_OK_BIT, &cmdq->state) ||
+	    !cmdq->use_event)
+		return;
+
+	while (get_next_valid_eqe(&cmdq->eq)) {
+		cmdq->eq.ci++;
+		got_event++;
+	}
+
+	if (got_event) {
+		cmdq->cq.cmdsn++;
+		erdma_polling_cmd_completions(cmdq);
+	}
+
+	notify_eq(&cmdq->eq);
+}
+
+static int erdma_poll_cmd_completion(struct erdma_comp_wait *comp_ctx,
+				     struct erdma_cmdq *cmdq, u32 timeout)
+{
+	unsigned long comp_timeout = jiffies + msecs_to_jiffies(timeout);
+
+	while (1) {
+		erdma_polling_cmd_completions(cmdq);
+		if (comp_ctx->cmd_status != ERDMA_CMD_STATUS_ISSUED)
+			break;
+
+		if (time_is_before_jiffies(comp_timeout))
+			return -ETIME;
+
+		msleep(20);
+	}
+
+	return 0;
+}
+
+static int erdma_wait_cmd_completion(struct erdma_comp_wait *comp_ctx,
+				     struct erdma_cmdq *cmdq, u32 timeout)
+{
+	unsigned long flags = 0;
+
+	wait_for_completion_timeout(&comp_ctx->wait_event,
+				    msecs_to_jiffies(timeout));
+
+	if (unlikely(comp_ctx->cmd_status != ERDMA_CMD_STATUS_FINISHED)) {
+		spin_lock_irqsave(&cmdq->cq.lock, flags);
+		comp_ctx->cmd_status = ERDMA_CMD_STATUS_TIMEOUT;
+		spin_unlock_irqrestore(&cmdq->cq.lock, flags);
+		return -ETIME;
+	}
+
+	return 0;
+}
+
+void erdma_cmdq_build_reqhdr(u64 *hdr, u32 mod, u32 op)
+{
+	*hdr = FIELD_PREP(ERDMA_CMD_HDR_SUB_MOD_MASK, mod) |
+	       FIELD_PREP(ERDMA_CMD_HDR_OPCODE_MASK, op);
+}
+
+int erdma_post_cmd_wait(struct erdma_cmdq *cmdq, u64 *req, u32 req_size,
+			u64 *resp0, u64 *resp1)
+{
+	struct erdma_comp_wait *comp_wait;
+	int ret;
+
+	if (!test_bit(ERDMA_CMDQ_STATE_OK_BIT, &cmdq->state))
+		return -ENODEV;
+
+	down(&cmdq->credits);
+
+	comp_wait = get_comp_wait(cmdq);
+	if (IS_ERR(comp_wait)) {
+		clear_bit(ERDMA_CMDQ_STATE_OK_BIT, &cmdq->state);
+		set_bit(ERDMA_CMDQ_STATE_CTX_ERR_BIT, &cmdq->state);
+		up(&cmdq->credits);
+		return PTR_ERR(comp_wait);
+	}
+
+	spin_lock(&cmdq->sq.lock);
+	push_cmdq_sqe(cmdq, req, req_size, comp_wait);
+	spin_unlock(&cmdq->sq.lock);
+
+	if (cmdq->use_event)
+		ret = erdma_wait_cmd_completion(comp_wait, cmdq,
+						ERDMA_CMDQ_TIMEOUT_MS);
+	else
+		ret = erdma_poll_cmd_completion(comp_wait, cmdq,
+						ERDMA_CMDQ_TIMEOUT_MS);
+
+	if (ret) {
+		set_bit(ERDMA_CMDQ_STATE_TIMEOUT_BIT, &cmdq->state);
+		clear_bit(ERDMA_CMDQ_STATE_OK_BIT, &cmdq->state);
+		goto out;
+	}
+
+	ret = comp_wait->comp_status;
+
+	if (resp0 && resp1) {
+		*resp0 = *((u64 *)&comp_wait->comp_data[0]);
+		*resp1 = *((u64 *)&comp_wait->comp_data[2]);
+	}
+	put_comp_wait(cmdq, comp_wait);
+
+out:
+	up(&cmdq->credits);
+
+	return ret;
+}
