drivers/net/ethernet/amazon/ena/ena_eth_com.c - hafnium/third_party/linux - Git at Google

 /*
  * Copyright 2015 Amazon.com, Inc. or its affiliates.
  *
  * This software is available to you under a choice of one of two
  * licenses.  You may choose to be licensed under the terms of the GNU
  * General Public License (GPL) Version 2, available from the file
  * COPYING in the main directory of this source tree, or the
  * BSD license below:
  *
  *     Redistribution and use in source and binary forms, with or
  *     without modification, are permitted provided that the following
  *     conditions are met:
  *
  *      - Redistributions of source code must retain the above
  *        copyright notice, this list of conditions and the following
  *        disclaimer.
  *
  *      - Redistributions in binary form must reproduce the above
  *        copyright notice, this list of conditions and the following
  *        disclaimer in the documentation and/or other materials
  *        provided with the distribution.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  */

 #include "ena_eth_com.h"

 static struct ena_eth_io_rx_cdesc_base *ena_com_get_next_rx_cdesc(
 	struct ena_com_io_cq *io_cq)
 {
 	struct ena_eth_io_rx_cdesc_base *cdesc;
 	u16 expected_phase, head_masked;
 	u16 desc_phase;

 	head_masked = io_cq->head & (io_cq->q_depth - 1);
 	expected_phase = io_cq->phase;

 	cdesc = (struct ena_eth_io_rx_cdesc_base *)(io_cq->cdesc_addr.virt_addr
 			+ (head_masked * io_cq->cdesc_entry_size_in_bytes));

 	desc_phase = (READ_ONCE(cdesc->status) & ENA_ETH_IO_RX_CDESC_BASE_PHASE_MASK) >>
 			ENA_ETH_IO_RX_CDESC_BASE_PHASE_SHIFT;

 	if (desc_phase != expected_phase)
 		return NULL;

 	/* Make sure we read the rest of the descriptor after the phase bit
 	 * has been read
 	 */
 	dma_rmb();

 	return cdesc;
 }

 static void *get_sq_desc_regular_queue(struct ena_com_io_sq *io_sq)
 {
 	u16 tail_masked;
 	u32 offset;

 	tail_masked = io_sq->tail & (io_sq->q_depth - 1);

 	offset = tail_masked * io_sq->desc_entry_size;

 	return (void *)((uintptr_t)io_sq->desc_addr.virt_addr + offset);
 }

 static int ena_com_write_bounce_buffer_to_dev(struct ena_com_io_sq *io_sq,
 						     u8 *bounce_buffer)
 {
 	struct ena_com_llq_info *llq_info = &io_sq->llq_info;

 	u16 dst_tail_mask;
 	u32 dst_offset;

 	dst_tail_mask = io_sq->tail & (io_sq->q_depth - 1);
 	dst_offset = dst_tail_mask * llq_info->desc_list_entry_size;

 	if (is_llq_max_tx_burst_exists(io_sq)) {
 		if (unlikely(!io_sq->entries_in_tx_burst_left)) {
 			pr_err("Error: trying to send more packets than tx burst allows\n");
 			return -ENOSPC;
 		}

 		io_sq->entries_in_tx_burst_left--;
 		pr_debug("decreasing entries_in_tx_burst_left of queue %d to %d\n",
 			 io_sq->qid, io_sq->entries_in_tx_burst_left);
 	}

 	/* Make sure everything was written into the bounce buffer before
 	 * writing the bounce buffer to the device
 	 */
 	wmb();

 	/* The line is completed. Copy it to dev */
 	__iowrite64_copy(io_sq->desc_addr.pbuf_dev_addr + dst_offset,
 			 bounce_buffer, (llq_info->desc_list_entry_size) / 8);

 	io_sq->tail++;

 	/* Switch phase bit in case of wrap around */
 	if (unlikely((io_sq->tail & (io_sq->q_depth - 1)) == 0))
 		io_sq->phase ^= 1;

 	return 0;
 }

 static int ena_com_write_header_to_bounce(struct ena_com_io_sq *io_sq,
 						 u8 *header_src,
 						 u16 header_len)
 {
 	struct ena_com_llq_pkt_ctrl *pkt_ctrl = &io_sq->llq_buf_ctrl;
 	struct ena_com_llq_info *llq_info = &io_sq->llq_info;
 	u8 *bounce_buffer = pkt_ctrl->curr_bounce_buf;
 	u16 header_offset;

 	if (unlikely(io_sq->mem_queue_type == ENA_ADMIN_PLACEMENT_POLICY_HOST))
 		return 0;

 	header_offset =
 		llq_info->descs_num_before_header * io_sq->desc_entry_size;

 	if (unlikely((header_offset + header_len) >
 		     llq_info->desc_list_entry_size)) {
 		pr_err("trying to write header larger than llq entry can accommodate\n");
 		return -EFAULT;
 	}

 	if (unlikely(!bounce_buffer)) {
 		pr_err("bounce buffer is NULL\n");
 		return -EFAULT;
 	}

 	memcpy(bounce_buffer + header_offset, header_src, header_len);

 	return 0;
 }

 static void *get_sq_desc_llq(struct ena_com_io_sq *io_sq)
 {
 	struct ena_com_llq_pkt_ctrl *pkt_ctrl = &io_sq->llq_buf_ctrl;
 	u8 *bounce_buffer;
 	void *sq_desc;

 	bounce_buffer = pkt_ctrl->curr_bounce_buf;

 	if (unlikely(!bounce_buffer)) {
 		pr_err("bounce buffer is NULL\n");
 		return NULL;
 	}

 	sq_desc = bounce_buffer + pkt_ctrl->idx * io_sq->desc_entry_size;
 	pkt_ctrl->idx++;
 	pkt_ctrl->descs_left_in_line--;

 	return sq_desc;
 }

 static int ena_com_close_bounce_buffer(struct ena_com_io_sq *io_sq)
 {
 	struct ena_com_llq_pkt_ctrl *pkt_ctrl = &io_sq->llq_buf_ctrl;
 	struct ena_com_llq_info *llq_info = &io_sq->llq_info;
 	int rc;

 	if (unlikely(io_sq->mem_queue_type == ENA_ADMIN_PLACEMENT_POLICY_HOST))
 		return 0;

 	/* bounce buffer was used, so write it and get a new one */
 	if (pkt_ctrl->idx) {
 		rc = ena_com_write_bounce_buffer_to_dev(io_sq,
 							pkt_ctrl->curr_bounce_buf);
 		if (unlikely(rc))
 			return rc;

 		pkt_ctrl->curr_bounce_buf =
 			ena_com_get_next_bounce_buffer(&io_sq->bounce_buf_ctrl);
 		memset(io_sq->llq_buf_ctrl.curr_bounce_buf,
 		       0x0, llq_info->desc_list_entry_size);
 	}

 	pkt_ctrl->idx = 0;
 	pkt_ctrl->descs_left_in_line = llq_info->descs_num_before_header;
 	return 0;
 }

 static void *get_sq_desc(struct ena_com_io_sq *io_sq)
 {
 	if (io_sq->mem_queue_type == ENA_ADMIN_PLACEMENT_POLICY_DEV)
 		return get_sq_desc_llq(io_sq);

 	return get_sq_desc_regular_queue(io_sq);
 }

 static int ena_com_sq_update_llq_tail(struct ena_com_io_sq *io_sq)
 {
 	struct ena_com_llq_pkt_ctrl *pkt_ctrl = &io_sq->llq_buf_ctrl;
 	struct ena_com_llq_info *llq_info = &io_sq->llq_info;
 	int rc;

 	if (!pkt_ctrl->descs_left_in_line) {
 		rc = ena_com_write_bounce_buffer_to_dev(io_sq,
 							pkt_ctrl->curr_bounce_buf);
 		if (unlikely(rc))
 			return rc;

 		pkt_ctrl->curr_bounce_buf =
 			ena_com_get_next_bounce_buffer(&io_sq->bounce_buf_ctrl);
 		memset(io_sq->llq_buf_ctrl.curr_bounce_buf,
 		       0x0, llq_info->desc_list_entry_size);

 		pkt_ctrl->idx = 0;
 		if (unlikely(llq_info->desc_stride_ctrl == ENA_ADMIN_SINGLE_DESC_PER_ENTRY))
 			pkt_ctrl->descs_left_in_line = 1;
 		else
 			pkt_ctrl->descs_left_in_line =
 			llq_info->desc_list_entry_size / io_sq->desc_entry_size;
 	}

 	return 0;
 }

 static int ena_com_sq_update_tail(struct ena_com_io_sq *io_sq)
 {
 	if (io_sq->mem_queue_type == ENA_ADMIN_PLACEMENT_POLICY_DEV)
 		return ena_com_sq_update_llq_tail(io_sq);

 	io_sq->tail++;

 	/* Switch phase bit in case of wrap around */
 	if (unlikely((io_sq->tail & (io_sq->q_depth - 1)) == 0))
 		io_sq->phase ^= 1;

 	return 0;
 }

 static struct ena_eth_io_rx_cdesc_base *
 	ena_com_rx_cdesc_idx_to_ptr(struct ena_com_io_cq *io_cq, u16 idx)
 {
 	idx &= (io_cq->q_depth - 1);
 	return (struct ena_eth_io_rx_cdesc_base *)
 		((uintptr_t)io_cq->cdesc_addr.virt_addr +
 		idx * io_cq->cdesc_entry_size_in_bytes);
 }

 static u16 ena_com_cdesc_rx_pkt_get(struct ena_com_io_cq *io_cq,
 					   u16 *first_cdesc_idx)
 {
 	struct ena_eth_io_rx_cdesc_base *cdesc;
 	u16 count = 0, head_masked;
 	u32 last = 0;

 	do {
 		cdesc = ena_com_get_next_rx_cdesc(io_cq);
 		if (!cdesc)
 			break;

 		ena_com_cq_inc_head(io_cq);
 		count++;
 		last = (READ_ONCE(cdesc->status) & ENA_ETH_IO_RX_CDESC_BASE_LAST_MASK) >>
 			ENA_ETH_IO_RX_CDESC_BASE_LAST_SHIFT;
 	} while (!last);

 	if (last) {
 		*first_cdesc_idx = io_cq->cur_rx_pkt_cdesc_start_idx;
 		count += io_cq->cur_rx_pkt_cdesc_count;

 		head_masked = io_cq->head & (io_cq->q_depth - 1);

 		io_cq->cur_rx_pkt_cdesc_count = 0;
 		io_cq->cur_rx_pkt_cdesc_start_idx = head_masked;

 		pr_debug("ena q_id: %d packets were completed. first desc idx %u descs# %d\n",
 			 io_cq->qid, *first_cdesc_idx, count);
 	} else {
 		io_cq->cur_rx_pkt_cdesc_count += count;
 		count = 0;
 	}

 	return count;
 }

 static int ena_com_create_and_store_tx_meta_desc(struct ena_com_io_sq *io_sq,
 							struct ena_com_tx_ctx *ena_tx_ctx)
 {
 	struct ena_eth_io_tx_meta_desc *meta_desc = NULL;
 	struct ena_com_tx_meta *ena_meta = &ena_tx_ctx->ena_meta;

 	meta_desc = get_sq_desc(io_sq);
 	memset(meta_desc, 0x0, sizeof(struct ena_eth_io_tx_meta_desc));

 	meta_desc->len_ctrl |= ENA_ETH_IO_TX_META_DESC_META_DESC_MASK;

 	meta_desc->len_ctrl |= ENA_ETH_IO_TX_META_DESC_EXT_VALID_MASK;

 	/* bits 0-9 of the mss */
 	meta_desc->word2 |= (ena_meta->mss <<
 		ENA_ETH_IO_TX_META_DESC_MSS_LO_SHIFT) &
 		ENA_ETH_IO_TX_META_DESC_MSS_LO_MASK;
 	/* bits 10-13 of the mss */
 	meta_desc->len_ctrl |= ((ena_meta->mss >> 10) <<
 		ENA_ETH_IO_TX_META_DESC_MSS_HI_SHIFT) &
 		ENA_ETH_IO_TX_META_DESC_MSS_HI_MASK;

 	/* Extended meta desc */
 	meta_desc->len_ctrl |= ENA_ETH_IO_TX_META_DESC_ETH_META_TYPE_MASK;
 	meta_desc->len_ctrl |= ENA_ETH_IO_TX_META_DESC_META_STORE_MASK;
 	meta_desc->len_ctrl |= (io_sq->phase <<
 		ENA_ETH_IO_TX_META_DESC_PHASE_SHIFT) &
 		ENA_ETH_IO_TX_META_DESC_PHASE_MASK;

 	meta_desc->len_ctrl |= ENA_ETH_IO_TX_META_DESC_FIRST_MASK;
 	meta_desc->word2 |= ena_meta->l3_hdr_len &
 		ENA_ETH_IO_TX_META_DESC_L3_HDR_LEN_MASK;
 	meta_desc->word2 |= (ena_meta->l3_hdr_offset <<
 		ENA_ETH_IO_TX_META_DESC_L3_HDR_OFF_SHIFT) &
 		ENA_ETH_IO_TX_META_DESC_L3_HDR_OFF_MASK;

 	meta_desc->word2 |= (ena_meta->l4_hdr_len <<
 		ENA_ETH_IO_TX_META_DESC_L4_HDR_LEN_IN_WORDS_SHIFT) &
 		ENA_ETH_IO_TX_META_DESC_L4_HDR_LEN_IN_WORDS_MASK;

 	meta_desc->len_ctrl |= ENA_ETH_IO_TX_META_DESC_META_STORE_MASK;

 	/* Cached the meta desc */
 	memcpy(&io_sq->cached_tx_meta, ena_meta,
 	       sizeof(struct ena_com_tx_meta));

 	return ena_com_sq_update_tail(io_sq);
 }

 static void ena_com_rx_set_flags(struct ena_com_rx_ctx *ena_rx_ctx,
 					struct ena_eth_io_rx_cdesc_base *cdesc)
 {
 	ena_rx_ctx->l3_proto = cdesc->status &
 		ENA_ETH_IO_RX_CDESC_BASE_L3_PROTO_IDX_MASK;
 	ena_rx_ctx->l4_proto =
 		(cdesc->status & ENA_ETH_IO_RX_CDESC_BASE_L4_PROTO_IDX_MASK) >>
 		ENA_ETH_IO_RX_CDESC_BASE_L4_PROTO_IDX_SHIFT;
 	ena_rx_ctx->l3_csum_err =
 		!!((cdesc->status & ENA_ETH_IO_RX_CDESC_BASE_L3_CSUM_ERR_MASK) >>
 		ENA_ETH_IO_RX_CDESC_BASE_L3_CSUM_ERR_SHIFT);
 	ena_rx_ctx->l4_csum_err =
 		!!((cdesc->status & ENA_ETH_IO_RX_CDESC_BASE_L4_CSUM_ERR_MASK) >>
 		ENA_ETH_IO_RX_CDESC_BASE_L4_CSUM_ERR_SHIFT);
 	ena_rx_ctx->l4_csum_checked =
 		!!((cdesc->status & ENA_ETH_IO_RX_CDESC_BASE_L4_CSUM_CHECKED_MASK) >>
 		ENA_ETH_IO_RX_CDESC_BASE_L4_CSUM_CHECKED_SHIFT);
 	ena_rx_ctx->hash = cdesc->hash;
 	ena_rx_ctx->frag =
 		(cdesc->status & ENA_ETH_IO_RX_CDESC_BASE_IPV4_FRAG_MASK) >>
 		ENA_ETH_IO_RX_CDESC_BASE_IPV4_FRAG_SHIFT;

 	pr_debug("ena_rx_ctx->l3_proto %d ena_rx_ctx->l4_proto %d\nena_rx_ctx->l3_csum_err %d ena_rx_ctx->l4_csum_err %d\nhash frag %d frag: %d cdesc_status: %x\n",
 		 ena_rx_ctx->l3_proto, ena_rx_ctx->l4_proto,
 		 ena_rx_ctx->l3_csum_err, ena_rx_ctx->l4_csum_err,
 		 ena_rx_ctx->hash, ena_rx_ctx->frag, cdesc->status);
 }

 /*****************************************************************************/
 /*****************************     API      **********************************/
 /*****************************************************************************/

 int ena_com_prepare_tx(struct ena_com_io_sq *io_sq,
 		       struct ena_com_tx_ctx *ena_tx_ctx,
 		       int *nb_hw_desc)
 {
 	struct ena_eth_io_tx_desc *desc = NULL;
 	struct ena_com_buf *ena_bufs = ena_tx_ctx->ena_bufs;
 	void *buffer_to_push = ena_tx_ctx->push_header;
 	u16 header_len = ena_tx_ctx->header_len;
 	u16 num_bufs = ena_tx_ctx->num_bufs;
 	u16 start_tail = io_sq->tail;
 	int i, rc;
 	bool have_meta;
 	u64 addr_hi;

 	WARN(io_sq->direction != ENA_COM_IO_QUEUE_DIRECTION_TX, "wrong Q type");

 	/* num_bufs +1 for potential meta desc */
 	if (unlikely(!ena_com_sq_have_enough_space(io_sq, num_bufs + 1))) {
 		pr_debug("Not enough space in the tx queue\n");
 		return -ENOMEM;
 	}

 	if (unlikely(header_len > io_sq->tx_max_header_size)) {
 		pr_err("header size is too large %d max header: %d\n",
 		       header_len, io_sq->tx_max_header_size);
 		return -EINVAL;
 	}

 	if (unlikely(io_sq->mem_queue_type == ENA_ADMIN_PLACEMENT_POLICY_DEV &&
 		     !buffer_to_push))
 		return -EINVAL;

 	rc = ena_com_write_header_to_bounce(io_sq, buffer_to_push, header_len);
 	if (unlikely(rc))
 		return rc;

 	have_meta = ena_tx_ctx->meta_valid && ena_com_meta_desc_changed(io_sq,
 			ena_tx_ctx);
 	if (have_meta) {
 		rc = ena_com_create_and_store_tx_meta_desc(io_sq, ena_tx_ctx);
 		if (unlikely(rc))
 			return rc;
 	}

 	/* If the caller doesn't want to send packets */
 	if (unlikely(!num_bufs && !header_len)) {
 		rc = ena_com_close_bounce_buffer(io_sq);
 		*nb_hw_desc = io_sq->tail - start_tail;
 		return rc;
 	}

 	desc = get_sq_desc(io_sq);
 	if (unlikely(!desc))
 		return -EFAULT;
 	memset(desc, 0x0, sizeof(struct ena_eth_io_tx_desc));

 	/* Set first desc when we don't have meta descriptor */
 	if (!have_meta)
 		desc->len_ctrl |= ENA_ETH_IO_TX_DESC_FIRST_MASK;

 	desc->buff_addr_hi_hdr_sz |= (header_len <<
 		ENA_ETH_IO_TX_DESC_HEADER_LENGTH_SHIFT) &
 		ENA_ETH_IO_TX_DESC_HEADER_LENGTH_MASK;
 	desc->len_ctrl |= (io_sq->phase << ENA_ETH_IO_TX_DESC_PHASE_SHIFT) &
 		ENA_ETH_IO_TX_DESC_PHASE_MASK;

 	desc->len_ctrl |= ENA_ETH_IO_TX_DESC_COMP_REQ_MASK;

 	/* Bits 0-9 */
 	desc->meta_ctrl |= (ena_tx_ctx->req_id <<
 		ENA_ETH_IO_TX_DESC_REQ_ID_LO_SHIFT) &
 		ENA_ETH_IO_TX_DESC_REQ_ID_LO_MASK;

 	desc->meta_ctrl |= (ena_tx_ctx->df <<
 		ENA_ETH_IO_TX_DESC_DF_SHIFT) &
 		ENA_ETH_IO_TX_DESC_DF_MASK;

 	/* Bits 10-15 */
 	desc->len_ctrl |= ((ena_tx_ctx->req_id >> 10) <<
 		ENA_ETH_IO_TX_DESC_REQ_ID_HI_SHIFT) &
 		ENA_ETH_IO_TX_DESC_REQ_ID_HI_MASK;

 	if (ena_tx_ctx->meta_valid) {
 		desc->meta_ctrl |= (ena_tx_ctx->tso_enable <<
 			ENA_ETH_IO_TX_DESC_TSO_EN_SHIFT) &
 			ENA_ETH_IO_TX_DESC_TSO_EN_MASK;
 		desc->meta_ctrl |= ena_tx_ctx->l3_proto &
 			ENA_ETH_IO_TX_DESC_L3_PROTO_IDX_MASK;
 		desc->meta_ctrl |= (ena_tx_ctx->l4_proto <<
 			ENA_ETH_IO_TX_DESC_L4_PROTO_IDX_SHIFT) &
 			ENA_ETH_IO_TX_DESC_L4_PROTO_IDX_MASK;
 		desc->meta_ctrl |= (ena_tx_ctx->l3_csum_enable <<
 			ENA_ETH_IO_TX_DESC_L3_CSUM_EN_SHIFT) &
 			ENA_ETH_IO_TX_DESC_L3_CSUM_EN_MASK;
 		desc->meta_ctrl |= (ena_tx_ctx->l4_csum_enable <<
 			ENA_ETH_IO_TX_DESC_L4_CSUM_EN_SHIFT) &
 			ENA_ETH_IO_TX_DESC_L4_CSUM_EN_MASK;
 		desc->meta_ctrl |= (ena_tx_ctx->l4_csum_partial <<
 			ENA_ETH_IO_TX_DESC_L4_CSUM_PARTIAL_SHIFT) &
 			ENA_ETH_IO_TX_DESC_L4_CSUM_PARTIAL_MASK;
 	}

 	for (i = 0; i < num_bufs; i++) {
 		/* The first desc share the same desc as the header */
 		if (likely(i != 0)) {
 			rc = ena_com_sq_update_tail(io_sq);
 			if (unlikely(rc))
 				return rc;

 			desc = get_sq_desc(io_sq);
 			if (unlikely(!desc))
 				return -EFAULT;

 			memset(desc, 0x0, sizeof(struct ena_eth_io_tx_desc));

 			desc->len_ctrl |= (io_sq->phase <<
 				ENA_ETH_IO_TX_DESC_PHASE_SHIFT) &
 				ENA_ETH_IO_TX_DESC_PHASE_MASK;
 		}

 		desc->len_ctrl |= ena_bufs->len &
 			ENA_ETH_IO_TX_DESC_LENGTH_MASK;

 		addr_hi = ((ena_bufs->paddr &
 			GENMASK_ULL(io_sq->dma_addr_bits - 1, 32)) >> 32);

 		desc->buff_addr_lo = (u32)ena_bufs->paddr;
 		desc->buff_addr_hi_hdr_sz |= addr_hi &
 			ENA_ETH_IO_TX_DESC_ADDR_HI_MASK;
 		ena_bufs++;
 	}

 	/* set the last desc indicator */
 	desc->len_ctrl |= ENA_ETH_IO_TX_DESC_LAST_MASK;

 	rc = ena_com_sq_update_tail(io_sq);
 	if (unlikely(rc))
 		return rc;

 	rc = ena_com_close_bounce_buffer(io_sq);

 	*nb_hw_desc = io_sq->tail - start_tail;
 	return rc;
 }

 int ena_com_rx_pkt(struct ena_com_io_cq *io_cq,
 		   struct ena_com_io_sq *io_sq,
 		   struct ena_com_rx_ctx *ena_rx_ctx)
 {
 	struct ena_com_rx_buf_info *ena_buf = &ena_rx_ctx->ena_bufs[0];
 	struct ena_eth_io_rx_cdesc_base *cdesc = NULL;
 	u16 cdesc_idx = 0;
 	u16 nb_hw_desc;
 	u16 i;

 	WARN(io_cq->direction != ENA_COM_IO_QUEUE_DIRECTION_RX, "wrong Q type");

 	nb_hw_desc = ena_com_cdesc_rx_pkt_get(io_cq, &cdesc_idx);
 	if (nb_hw_desc == 0) {
 		ena_rx_ctx->descs = nb_hw_desc;
 		return 0;
 	}

 	pr_debug("fetch rx packet: queue %d completed desc: %d\n", io_cq->qid,
 		 nb_hw_desc);

 	if (unlikely(nb_hw_desc > ena_rx_ctx->max_bufs)) {
 		pr_err("Too many RX cdescs (%d) > MAX(%d)\n", nb_hw_desc,
 		       ena_rx_ctx->max_bufs);
 		return -ENOSPC;
 	}

 	for (i = 0; i < nb_hw_desc; i++) {
 		cdesc = ena_com_rx_cdesc_idx_to_ptr(io_cq, cdesc_idx + i);

 		ena_buf->len = cdesc->length;
 		ena_buf->req_id = cdesc->req_id;
 		ena_buf++;
 	}

 	/* Update SQ head ptr */
 	io_sq->next_to_comp += nb_hw_desc;

 	pr_debug("[%s][QID#%d] Updating SQ head to: %d\n", __func__, io_sq->qid,
 		 io_sq->next_to_comp);

 	/* Get rx flags from the last pkt */
 	ena_com_rx_set_flags(ena_rx_ctx, cdesc);

 	ena_rx_ctx->descs = nb_hw_desc;
 	return 0;
 }

 int ena_com_add_single_rx_desc(struct ena_com_io_sq *io_sq,
 			       struct ena_com_buf *ena_buf,
 			       u16 req_id)
 {
 	struct ena_eth_io_rx_desc *desc;

 	WARN(io_sq->direction != ENA_COM_IO_QUEUE_DIRECTION_RX, "wrong Q type");

 	if (unlikely(!ena_com_sq_have_enough_space(io_sq, 1)))
 		return -ENOSPC;

 	desc = get_sq_desc(io_sq);
 	if (unlikely(!desc))
 		return -EFAULT;

 	memset(desc, 0x0, sizeof(struct ena_eth_io_rx_desc));

 	desc->length = ena_buf->len;

 	desc->ctrl = ENA_ETH_IO_RX_DESC_FIRST_MASK;
 	desc->ctrl |= ENA_ETH_IO_RX_DESC_LAST_MASK;
 	desc->ctrl |= io_sq->phase & ENA_ETH_IO_RX_DESC_PHASE_MASK;
 	desc->ctrl |= ENA_ETH_IO_RX_DESC_COMP_REQ_MASK;

 	desc->req_id = req_id;

 	desc->buff_addr_lo = (u32)ena_buf->paddr;
 	desc->buff_addr_hi =
 		((ena_buf->paddr & GENMASK_ULL(io_sq->dma_addr_bits - 1, 32)) >> 32);

 	return ena_com_sq_update_tail(io_sq);
 }

 bool ena_com_cq_empty(struct ena_com_io_cq *io_cq)
 {
 	struct ena_eth_io_rx_cdesc_base *cdesc;

 	cdesc = ena_com_get_next_rx_cdesc(io_cq);
 	if (cdesc)
 		return false;
 	else
 		return true;
 }
	/*
	* Copyright 2015 Amazon.com, Inc. or its affiliates.
	*
	* This software is available to you under a choice of one of two
	* licenses. You may choose to be licensed under the terms of the GNU
	* General Public License (GPL) Version 2, available from the file
	* COPYING in the main directory of this source tree, or the
	* BSD license below:
	*
	* Redistribution and use in source and binary forms, with or
	* without modification, are permitted provided that the following
	* conditions are met:
	*
	* - Redistributions of source code must retain the above
	* copyright notice, this list of conditions and the following
	* disclaimer.
	*
	* - Redistributions in binary form must reproduce the above
	* copyright notice, this list of conditions and the following
	* disclaimer in the documentation and/or other materials
	* provided with the distribution.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
	* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
	* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
	* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	* SOFTWARE.
	*/

	#include "ena_eth_com.h"

	static struct ena_eth_io_rx_cdesc_base *ena_com_get_next_rx_cdesc(
	struct ena_com_io_cq *io_cq)
	{
	struct ena_eth_io_rx_cdesc_base *cdesc;
	u16 expected_phase, head_masked;
	u16 desc_phase;

	head_masked = io_cq->head & (io_cq->q_depth - 1);
	expected_phase = io_cq->phase;

	cdesc = (struct ena_eth_io_rx_cdesc_base *)(io_cq->cdesc_addr.virt_addr
	+ (head_masked * io_cq->cdesc_entry_size_in_bytes));

	desc_phase = (READ_ONCE(cdesc->status) & ENA_ETH_IO_RX_CDESC_BASE_PHASE_MASK) >>
	ENA_ETH_IO_RX_CDESC_BASE_PHASE_SHIFT;

	if (desc_phase != expected_phase)
	return NULL;

	/* Make sure we read the rest of the descriptor after the phase bit
	* has been read
	*/
	dma_rmb();

	return cdesc;
	}

	static void get_sq_desc_regular_queue(struct ena_com_io_sq io_sq)
	{
	u16 tail_masked;
	u32 offset;

	tail_masked = io_sq->tail & (io_sq->q_depth - 1);

	offset = tail_masked * io_sq->desc_entry_size;

	return (void *)((uintptr_t)io_sq->desc_addr.virt_addr + offset);
	}

	static int ena_com_write_bounce_buffer_to_dev(struct ena_com_io_sq *io_sq,
	u8 *bounce_buffer)
	{
	struct ena_com_llq_info *llq_info = &io_sq->llq_info;

	u16 dst_tail_mask;
	u32 dst_offset;

	dst_tail_mask = io_sq->tail & (io_sq->q_depth - 1);
	dst_offset = dst_tail_mask * llq_info->desc_list_entry_size;

	if (is_llq_max_tx_burst_exists(io_sq)) {
	if (unlikely(!io_sq->entries_in_tx_burst_left)) {
	pr_err("Error: trying to send more packets than tx burst allows\n");
	return -ENOSPC;
	}

	io_sq->entries_in_tx_burst_left--;
	pr_debug("decreasing entries_in_tx_burst_left of queue %d to %d\n",
	io_sq->qid, io_sq->entries_in_tx_burst_left);
	}

	/* Make sure everything was written into the bounce buffer before
	* writing the bounce buffer to the device
	*/
	wmb();

	/* The line is completed. Copy it to dev */
	__iowrite64_copy(io_sq->desc_addr.pbuf_dev_addr + dst_offset,
	bounce_buffer, (llq_info->desc_list_entry_size) / 8);

	io_sq->tail++;

	/* Switch phase bit in case of wrap around */
	if (unlikely((io_sq->tail & (io_sq->q_depth - 1)) == 0))
	io_sq->phase ^= 1;

	return 0;
	}

	static int ena_com_write_header_to_bounce(struct ena_com_io_sq *io_sq,
	u8 *header_src,
	u16 header_len)
	{
	struct ena_com_llq_pkt_ctrl *pkt_ctrl = &io_sq->llq_buf_ctrl;
	struct ena_com_llq_info *llq_info = &io_sq->llq_info;
	u8 *bounce_buffer = pkt_ctrl->curr_bounce_buf;
	u16 header_offset;

	if (unlikely(io_sq->mem_queue_type == ENA_ADMIN_PLACEMENT_POLICY_HOST))
	return 0;

	header_offset =
	llq_info->descs_num_before_header * io_sq->desc_entry_size;

	if (unlikely((header_offset + header_len) >
	llq_info->desc_list_entry_size)) {
	pr_err("trying to write header larger than llq entry can accommodate\n");
	return -EFAULT;
	}

	if (unlikely(!bounce_buffer)) {
	pr_err("bounce buffer is NULL\n");
	return -EFAULT;
	}

	memcpy(bounce_buffer + header_offset, header_src, header_len);

	return 0;
	}

	static void get_sq_desc_llq(struct ena_com_io_sq io_sq)
	{
	struct ena_com_llq_pkt_ctrl *pkt_ctrl = &io_sq->llq_buf_ctrl;
	u8 *bounce_buffer;
	void *sq_desc;

	bounce_buffer = pkt_ctrl->curr_bounce_buf;

	if (unlikely(!bounce_buffer)) {
	pr_err("bounce buffer is NULL\n");
	return NULL;
	}

	sq_desc = bounce_buffer + pkt_ctrl->idx * io_sq->desc_entry_size;
	pkt_ctrl->idx++;
	pkt_ctrl->descs_left_in_line--;

	return sq_desc;
	}

	static int ena_com_close_bounce_buffer(struct ena_com_io_sq *io_sq)
	{
	struct ena_com_llq_pkt_ctrl *pkt_ctrl = &io_sq->llq_buf_ctrl;
	struct ena_com_llq_info *llq_info = &io_sq->llq_info;
	int rc;

	if (unlikely(io_sq->mem_queue_type == ENA_ADMIN_PLACEMENT_POLICY_HOST))
	return 0;

	/* bounce buffer was used, so write it and get a new one */
	if (pkt_ctrl->idx) {
	rc = ena_com_write_bounce_buffer_to_dev(io_sq,
	pkt_ctrl->curr_bounce_buf);
	if (unlikely(rc))
	return rc;

	pkt_ctrl->curr_bounce_buf =
	ena_com_get_next_bounce_buffer(&io_sq->bounce_buf_ctrl);
	memset(io_sq->llq_buf_ctrl.curr_bounce_buf,
	0x0, llq_info->desc_list_entry_size);
	}

	pkt_ctrl->idx = 0;
	pkt_ctrl->descs_left_in_line = llq_info->descs_num_before_header;
	return 0;
	}

	static void get_sq_desc(struct ena_com_io_sq io_sq)
	{
	if (io_sq->mem_queue_type == ENA_ADMIN_PLACEMENT_POLICY_DEV)
	return get_sq_desc_llq(io_sq);

	return get_sq_desc_regular_queue(io_sq);
	}

	static int ena_com_sq_update_llq_tail(struct ena_com_io_sq *io_sq)
	{
	struct ena_com_llq_pkt_ctrl *pkt_ctrl = &io_sq->llq_buf_ctrl;
	struct ena_com_llq_info *llq_info = &io_sq->llq_info;
	int rc;

	if (!pkt_ctrl->descs_left_in_line) {
	rc = ena_com_write_bounce_buffer_to_dev(io_sq,
	pkt_ctrl->curr_bounce_buf);
	if (unlikely(rc))
	return rc;

	pkt_ctrl->curr_bounce_buf =
	ena_com_get_next_bounce_buffer(&io_sq->bounce_buf_ctrl);
	memset(io_sq->llq_buf_ctrl.curr_bounce_buf,
	0x0, llq_info->desc_list_entry_size);

	pkt_ctrl->idx = 0;
	if (unlikely(llq_info->desc_stride_ctrl == ENA_ADMIN_SINGLE_DESC_PER_ENTRY))
	pkt_ctrl->descs_left_in_line = 1;
	else
	pkt_ctrl->descs_left_in_line =
	llq_info->desc_list_entry_size / io_sq->desc_entry_size;
	}

	return 0;
	}

	static int ena_com_sq_update_tail(struct ena_com_io_sq *io_sq)
	{
	if (io_sq->mem_queue_type == ENA_ADMIN_PLACEMENT_POLICY_DEV)
	return ena_com_sq_update_llq_tail(io_sq);

	io_sq->tail++;

	/* Switch phase bit in case of wrap around */
	if (unlikely((io_sq->tail & (io_sq->q_depth - 1)) == 0))
	io_sq->phase ^= 1;

	return 0;
	}

	static struct ena_eth_io_rx_cdesc_base *
	ena_com_rx_cdesc_idx_to_ptr(struct ena_com_io_cq *io_cq, u16 idx)
	{
	idx &= (io_cq->q_depth - 1);
	return (struct ena_eth_io_rx_cdesc_base *)
	((uintptr_t)io_cq->cdesc_addr.virt_addr +
	idx * io_cq->cdesc_entry_size_in_bytes);
	}

	static u16 ena_com_cdesc_rx_pkt_get(struct ena_com_io_cq *io_cq,
	u16 *first_cdesc_idx)
	{
	struct ena_eth_io_rx_cdesc_base *cdesc;
	u16 count = 0, head_masked;
	u32 last = 0;

	do {
	cdesc = ena_com_get_next_rx_cdesc(io_cq);
	if (!cdesc)
	break;

	ena_com_cq_inc_head(io_cq);
	count++;
	last = (READ_ONCE(cdesc->status) & ENA_ETH_IO_RX_CDESC_BASE_LAST_MASK) >>
	ENA_ETH_IO_RX_CDESC_BASE_LAST_SHIFT;
	} while (!last);

	if (last) {
	*first_cdesc_idx = io_cq->cur_rx_pkt_cdesc_start_idx;
	count += io_cq->cur_rx_pkt_cdesc_count;

	head_masked = io_cq->head & (io_cq->q_depth - 1);

	io_cq->cur_rx_pkt_cdesc_count = 0;
	io_cq->cur_rx_pkt_cdesc_start_idx = head_masked;

	pr_debug("ena q_id: %d packets were completed. first desc idx %u descs# %d\n",
	io_cq->qid, *first_cdesc_idx, count);
	} else {
	io_cq->cur_rx_pkt_cdesc_count += count;
	count = 0;
	}

	return count;
	}

	static int ena_com_create_and_store_tx_meta_desc(struct ena_com_io_sq *io_sq,
	struct ena_com_tx_ctx *ena_tx_ctx)
	{
	struct ena_eth_io_tx_meta_desc *meta_desc = NULL;
	struct ena_com_tx_meta *ena_meta = &ena_tx_ctx->ena_meta;

	meta_desc = get_sq_desc(io_sq);
	memset(meta_desc, 0x0, sizeof(struct ena_eth_io_tx_meta_desc));

	meta_desc->len_ctrl \|= ENA_ETH_IO_TX_META_DESC_META_DESC_MASK;

	meta_desc->len_ctrl \|= ENA_ETH_IO_TX_META_DESC_EXT_VALID_MASK;

	/* bits 0-9 of the mss */
	meta_desc->word2 \|= (ena_meta->mss <<
	ENA_ETH_IO_TX_META_DESC_MSS_LO_SHIFT) &
	ENA_ETH_IO_TX_META_DESC_MSS_LO_MASK;
	/* bits 10-13 of the mss */
	meta_desc->len_ctrl \|= ((ena_meta->mss >> 10) <<
	ENA_ETH_IO_TX_META_DESC_MSS_HI_SHIFT) &
	ENA_ETH_IO_TX_META_DESC_MSS_HI_MASK;

	/* Extended meta desc */
	meta_desc->len_ctrl \|= ENA_ETH_IO_TX_META_DESC_ETH_META_TYPE_MASK;
	meta_desc->len_ctrl \|= ENA_ETH_IO_TX_META_DESC_META_STORE_MASK;
	meta_desc->len_ctrl \|= (io_sq->phase <<
	ENA_ETH_IO_TX_META_DESC_PHASE_SHIFT) &
	ENA_ETH_IO_TX_META_DESC_PHASE_MASK;

	meta_desc->len_ctrl \|= ENA_ETH_IO_TX_META_DESC_FIRST_MASK;
	meta_desc->word2 \|= ena_meta->l3_hdr_len &
	ENA_ETH_IO_TX_META_DESC_L3_HDR_LEN_MASK;
	meta_desc->word2 \|= (ena_meta->l3_hdr_offset <<
	ENA_ETH_IO_TX_META_DESC_L3_HDR_OFF_SHIFT) &
	ENA_ETH_IO_TX_META_DESC_L3_HDR_OFF_MASK;

	meta_desc->word2 \|= (ena_meta->l4_hdr_len <<
	ENA_ETH_IO_TX_META_DESC_L4_HDR_LEN_IN_WORDS_SHIFT) &
	ENA_ETH_IO_TX_META_DESC_L4_HDR_LEN_IN_WORDS_MASK;

	meta_desc->len_ctrl \|= ENA_ETH_IO_TX_META_DESC_META_STORE_MASK;

	/* Cached the meta desc */
	memcpy(&io_sq->cached_tx_meta, ena_meta,
	sizeof(struct ena_com_tx_meta));

	return ena_com_sq_update_tail(io_sq);
	}

	static void ena_com_rx_set_flags(struct ena_com_rx_ctx *ena_rx_ctx,
	struct ena_eth_io_rx_cdesc_base *cdesc)
	{
	ena_rx_ctx->l3_proto = cdesc->status &
	ENA_ETH_IO_RX_CDESC_BASE_L3_PROTO_IDX_MASK;
	ena_rx_ctx->l4_proto =
	(cdesc->status & ENA_ETH_IO_RX_CDESC_BASE_L4_PROTO_IDX_MASK) >>
	ENA_ETH_IO_RX_CDESC_BASE_L4_PROTO_IDX_SHIFT;
	ena_rx_ctx->l3_csum_err =
	!!((cdesc->status & ENA_ETH_IO_RX_CDESC_BASE_L3_CSUM_ERR_MASK) >>
	ENA_ETH_IO_RX_CDESC_BASE_L3_CSUM_ERR_SHIFT);
	ena_rx_ctx->l4_csum_err =
	!!((cdesc->status & ENA_ETH_IO_RX_CDESC_BASE_L4_CSUM_ERR_MASK) >>
	ENA_ETH_IO_RX_CDESC_BASE_L4_CSUM_ERR_SHIFT);
	ena_rx_ctx->l4_csum_checked =
	!!((cdesc->status & ENA_ETH_IO_RX_CDESC_BASE_L4_CSUM_CHECKED_MASK) >>
	ENA_ETH_IO_RX_CDESC_BASE_L4_CSUM_CHECKED_SHIFT);
	ena_rx_ctx->hash = cdesc->hash;
	ena_rx_ctx->frag =
	(cdesc->status & ENA_ETH_IO_RX_CDESC_BASE_IPV4_FRAG_MASK) >>
	ENA_ETH_IO_RX_CDESC_BASE_IPV4_FRAG_SHIFT;

	pr_debug("ena_rx_ctx->l3_proto %d ena_rx_ctx->l4_proto %d\nena_rx_ctx->l3_csum_err %d ena_rx_ctx->l4_csum_err %d\nhash frag %d frag: %d cdesc_status: %x\n",
	ena_rx_ctx->l3_proto, ena_rx_ctx->l4_proto,
	ena_rx_ctx->l3_csum_err, ena_rx_ctx->l4_csum_err,
	ena_rx_ctx->hash, ena_rx_ctx->frag, cdesc->status);
	}

	/*****************************************************************************/
	/*************************** API ********************************/
	/*****************************************************************************/

	int ena_com_prepare_tx(struct ena_com_io_sq *io_sq,
	struct ena_com_tx_ctx *ena_tx_ctx,
	int *nb_hw_desc)
	{
	struct ena_eth_io_tx_desc *desc = NULL;
	struct ena_com_buf *ena_bufs = ena_tx_ctx->ena_bufs;
	void *buffer_to_push = ena_tx_ctx->push_header;
	u16 header_len = ena_tx_ctx->header_len;
	u16 num_bufs = ena_tx_ctx->num_bufs;
	u16 start_tail = io_sq->tail;
	int i, rc;
	bool have_meta;
	u64 addr_hi;

	WARN(io_sq->direction != ENA_COM_IO_QUEUE_DIRECTION_TX, "wrong Q type");

	/* num_bufs +1 for potential meta desc */
	if (unlikely(!ena_com_sq_have_enough_space(io_sq, num_bufs + 1))) {
	pr_debug("Not enough space in the tx queue\n");
	return -ENOMEM;
	}

	if (unlikely(header_len > io_sq->tx_max_header_size)) {
	pr_err("header size is too large %d max header: %d\n",
	header_len, io_sq->tx_max_header_size);
	return -EINVAL;
	}

	if (unlikely(io_sq->mem_queue_type == ENA_ADMIN_PLACEMENT_POLICY_DEV &&
	!buffer_to_push))
	return -EINVAL;

	rc = ena_com_write_header_to_bounce(io_sq, buffer_to_push, header_len);
	if (unlikely(rc))
	return rc;

	have_meta = ena_tx_ctx->meta_valid && ena_com_meta_desc_changed(io_sq,
	ena_tx_ctx);
	if (have_meta) {
	rc = ena_com_create_and_store_tx_meta_desc(io_sq, ena_tx_ctx);
	if (unlikely(rc))
	return rc;
	}

	/* If the caller doesn't want to send packets */
	if (unlikely(!num_bufs && !header_len)) {
	rc = ena_com_close_bounce_buffer(io_sq);
	*nb_hw_desc = io_sq->tail - start_tail;
	return rc;
	}

	desc = get_sq_desc(io_sq);
	if (unlikely(!desc))
	return -EFAULT;
	memset(desc, 0x0, sizeof(struct ena_eth_io_tx_desc));

	/* Set first desc when we don't have meta descriptor */
	if (!have_meta)
	desc->len_ctrl \|= ENA_ETH_IO_TX_DESC_FIRST_MASK;

	desc->buff_addr_hi_hdr_sz \|= (header_len <<
	ENA_ETH_IO_TX_DESC_HEADER_LENGTH_SHIFT) &
	ENA_ETH_IO_TX_DESC_HEADER_LENGTH_MASK;
	desc->len_ctrl \|= (io_sq->phase << ENA_ETH_IO_TX_DESC_PHASE_SHIFT) &
	ENA_ETH_IO_TX_DESC_PHASE_MASK;

	desc->len_ctrl \|= ENA_ETH_IO_TX_DESC_COMP_REQ_MASK;

	/* Bits 0-9 */
	desc->meta_ctrl \|= (ena_tx_ctx->req_id <<
	ENA_ETH_IO_TX_DESC_REQ_ID_LO_SHIFT) &
	ENA_ETH_IO_TX_DESC_REQ_ID_LO_MASK;

	desc->meta_ctrl \|= (ena_tx_ctx->df <<
	ENA_ETH_IO_TX_DESC_DF_SHIFT) &
	ENA_ETH_IO_TX_DESC_DF_MASK;

	/* Bits 10-15 */
	desc->len_ctrl \|= ((ena_tx_ctx->req_id >> 10) <<
	ENA_ETH_IO_TX_DESC_REQ_ID_HI_SHIFT) &
	ENA_ETH_IO_TX_DESC_REQ_ID_HI_MASK;

	if (ena_tx_ctx->meta_valid) {
	desc->meta_ctrl \|= (ena_tx_ctx->tso_enable <<
	ENA_ETH_IO_TX_DESC_TSO_EN_SHIFT) &
	ENA_ETH_IO_TX_DESC_TSO_EN_MASK;
	desc->meta_ctrl \|= ena_tx_ctx->l3_proto &
	ENA_ETH_IO_TX_DESC_L3_PROTO_IDX_MASK;
	desc->meta_ctrl \|= (ena_tx_ctx->l4_proto <<
	ENA_ETH_IO_TX_DESC_L4_PROTO_IDX_SHIFT) &
	ENA_ETH_IO_TX_DESC_L4_PROTO_IDX_MASK;
	desc->meta_ctrl \|= (ena_tx_ctx->l3_csum_enable <<
	ENA_ETH_IO_TX_DESC_L3_CSUM_EN_SHIFT) &
	ENA_ETH_IO_TX_DESC_L3_CSUM_EN_MASK;
	desc->meta_ctrl \|= (ena_tx_ctx->l4_csum_enable <<
	ENA_ETH_IO_TX_DESC_L4_CSUM_EN_SHIFT) &
	ENA_ETH_IO_TX_DESC_L4_CSUM_EN_MASK;
	desc->meta_ctrl \|= (ena_tx_ctx->l4_csum_partial <<
	ENA_ETH_IO_TX_DESC_L4_CSUM_PARTIAL_SHIFT) &
	ENA_ETH_IO_TX_DESC_L4_CSUM_PARTIAL_MASK;
	}

	for (i = 0; i < num_bufs; i++) {
	/* The first desc share the same desc as the header */
	if (likely(i != 0)) {
	rc = ena_com_sq_update_tail(io_sq);
	if (unlikely(rc))
	return rc;

	desc = get_sq_desc(io_sq);
	if (unlikely(!desc))
	return -EFAULT;

	memset(desc, 0x0, sizeof(struct ena_eth_io_tx_desc));

	desc->len_ctrl \|= (io_sq->phase <<
	ENA_ETH_IO_TX_DESC_PHASE_SHIFT) &
	ENA_ETH_IO_TX_DESC_PHASE_MASK;
	}

	desc->len_ctrl \|= ena_bufs->len &
	ENA_ETH_IO_TX_DESC_LENGTH_MASK;

	addr_hi = ((ena_bufs->paddr &
	GENMASK_ULL(io_sq->dma_addr_bits - 1, 32)) >> 32);

	desc->buff_addr_lo = (u32)ena_bufs->paddr;
	desc->buff_addr_hi_hdr_sz \|= addr_hi &
	ENA_ETH_IO_TX_DESC_ADDR_HI_MASK;
	ena_bufs++;
	}

	/* set the last desc indicator */
	desc->len_ctrl \|= ENA_ETH_IO_TX_DESC_LAST_MASK;

	rc = ena_com_sq_update_tail(io_sq);
	if (unlikely(rc))
	return rc;

	rc = ena_com_close_bounce_buffer(io_sq);

	*nb_hw_desc = io_sq->tail - start_tail;
	return rc;
	}

	int ena_com_rx_pkt(struct ena_com_io_cq *io_cq,
	struct ena_com_io_sq *io_sq,
	struct ena_com_rx_ctx *ena_rx_ctx)
	{
	struct ena_com_rx_buf_info *ena_buf = &ena_rx_ctx->ena_bufs[0];
	struct ena_eth_io_rx_cdesc_base *cdesc = NULL;
	u16 cdesc_idx = 0;
	u16 nb_hw_desc;
	u16 i;

	WARN(io_cq->direction != ENA_COM_IO_QUEUE_DIRECTION_RX, "wrong Q type");

	nb_hw_desc = ena_com_cdesc_rx_pkt_get(io_cq, &cdesc_idx);
	if (nb_hw_desc == 0) {
	ena_rx_ctx->descs = nb_hw_desc;
	return 0;
	}

	pr_debug("fetch rx packet: queue %d completed desc: %d\n", io_cq->qid,
	nb_hw_desc);

	if (unlikely(nb_hw_desc > ena_rx_ctx->max_bufs)) {
	pr_err("Too many RX cdescs (%d) > MAX(%d)\n", nb_hw_desc,
	ena_rx_ctx->max_bufs);
	return -ENOSPC;
	}

	for (i = 0; i < nb_hw_desc; i++) {
	cdesc = ena_com_rx_cdesc_idx_to_ptr(io_cq, cdesc_idx + i);

	ena_buf->len = cdesc->length;
	ena_buf->req_id = cdesc->req_id;
	ena_buf++;
	}

	/* Update SQ head ptr */
	io_sq->next_to_comp += nb_hw_desc;

	pr_debug("[%s][QID#%d] Updating SQ head to: %d\n", __func__, io_sq->qid,
	io_sq->next_to_comp);

	/* Get rx flags from the last pkt */
	ena_com_rx_set_flags(ena_rx_ctx, cdesc);

	ena_rx_ctx->descs = nb_hw_desc;
	return 0;
	}

	int ena_com_add_single_rx_desc(struct ena_com_io_sq *io_sq,
	struct ena_com_buf *ena_buf,
	u16 req_id)
	{
	struct ena_eth_io_rx_desc *desc;

	WARN(io_sq->direction != ENA_COM_IO_QUEUE_DIRECTION_RX, "wrong Q type");

	if (unlikely(!ena_com_sq_have_enough_space(io_sq, 1)))
	return -ENOSPC;

	desc = get_sq_desc(io_sq);
	if (unlikely(!desc))
	return -EFAULT;

	memset(desc, 0x0, sizeof(struct ena_eth_io_rx_desc));

	desc->length = ena_buf->len;

	desc->ctrl = ENA_ETH_IO_RX_DESC_FIRST_MASK;
	desc->ctrl \|= ENA_ETH_IO_RX_DESC_LAST_MASK;
	desc->ctrl \|= io_sq->phase & ENA_ETH_IO_RX_DESC_PHASE_MASK;
	desc->ctrl \|= ENA_ETH_IO_RX_DESC_COMP_REQ_MASK;

	desc->req_id = req_id;

	desc->buff_addr_lo = (u32)ena_buf->paddr;
	desc->buff_addr_hi =
	((ena_buf->paddr & GENMASK_ULL(io_sq->dma_addr_bits - 1, 32)) >> 32);

	return ena_com_sq_update_tail(io_sq);
	}

	bool ena_com_cq_empty(struct ena_com_io_cq *io_cq)
	{
	struct ena_eth_io_rx_cdesc_base *cdesc;

	cdesc = ena_com_get_next_rx_cdesc(io_cq);
	if (cdesc)
	return false;
	else
	return true;
	}