1 files changed, 406 insertions, 0 deletions

diff --git a/kernel/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c b/kernel/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
new file mode 100644
index 000000000..1341b1d3c
--- /dev/null
+++ b/kernel/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
@@ -0,0 +1,406 @@
+/*
+ * Copyright (c) 2015, Mellanox Technologies. All rights reserved.
+ *
+ * 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
+ * OpenIB.org 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 <linux/tcp.h>
+#include <linux/if_vlan.h>
+#include "en.h"
+
+#define MLX5E_SQ_NOPS_ROOM  MLX5_SEND_WQE_MAX_WQEBBS
+#define MLX5E_SQ_STOP_ROOM (MLX5_SEND_WQE_MAX_WQEBBS +\
+			    MLX5E_SQ_NOPS_ROOM)
+
+void mlx5e_send_nop(struct mlx5e_sq *sq, bool notify_hw)
+{
+	struct mlx5_wq_cyc                *wq  = &sq->wq;
+
+	u16 pi = sq->pc & wq->sz_m1;
+	struct mlx5e_tx_wqe              *wqe  = mlx5_wq_cyc_get_wqe(wq, pi);
+
+	struct mlx5_wqe_ctrl_seg         *cseg = &wqe->ctrl;
+
+	memset(cseg, 0, sizeof(*cseg));
+
+	cseg->opmod_idx_opcode = cpu_to_be32((sq->pc << 8) | MLX5_OPCODE_NOP);
+	cseg->qpn_ds           = cpu_to_be32((sq->sqn << 8) | 0x01);
+
+	sq->skb[pi] = NULL;
+	sq->pc++;
+
+	if (notify_hw) {
+		cseg->fm_ce_se = MLX5_WQE_CTRL_CQ_UPDATE;
+		mlx5e_tx_notify_hw(sq, wqe, 0);
+	}
+}
+
+static inline void mlx5e_tx_dma_unmap(struct device *pdev,
+				      struct mlx5e_sq_dma *dma)
+{
+	switch (dma->type) {
+	case MLX5E_DMA_MAP_SINGLE:
+		dma_unmap_single(pdev, dma->addr, dma->size, DMA_TO_DEVICE);
+		break;
+	case MLX5E_DMA_MAP_PAGE:
+		dma_unmap_page(pdev, dma->addr, dma->size, DMA_TO_DEVICE);
+		break;
+	default:
+		WARN_ONCE(true, "mlx5e_tx_dma_unmap unknown DMA type!\n");
+	}
+}
+
+static inline void mlx5e_dma_push(struct mlx5e_sq *sq,
+				  dma_addr_t addr,
+				  u32 size,
+				  enum mlx5e_dma_map_type map_type)
+{
+	sq->dma_fifo[sq->dma_fifo_pc & sq->dma_fifo_mask].addr = addr;
+	sq->dma_fifo[sq->dma_fifo_pc & sq->dma_fifo_mask].size = size;
+	sq->dma_fifo[sq->dma_fifo_pc & sq->dma_fifo_mask].type = map_type;
+	sq->dma_fifo_pc++;
+}
+
+static inline struct mlx5e_sq_dma *mlx5e_dma_get(struct mlx5e_sq *sq, u32 i)
+{
+	return &sq->dma_fifo[i & sq->dma_fifo_mask];
+}
+
+static void mlx5e_dma_unmap_wqe_err(struct mlx5e_sq *sq, struct sk_buff *skb)
+{
+	int i;
+
+	for (i = 0; i < MLX5E_TX_SKB_CB(skb)->num_dma; i++) {
+		struct mlx5e_sq_dma *last_pushed_dma =
+			mlx5e_dma_get(sq, --sq->dma_fifo_pc);
+
+		mlx5e_tx_dma_unmap(sq->pdev, last_pushed_dma);
+	}
+}
+
+u16 mlx5e_select_queue(struct net_device *dev, struct sk_buff *skb,
+		       void *accel_priv, select_queue_fallback_t fallback)
+{
+	struct mlx5e_priv *priv = netdev_priv(dev);
+	int channel_ix = fallback(dev, skb);
+	int up = skb_vlan_tag_present(skb)        ?
+		 skb->vlan_tci >> VLAN_PRIO_SHIFT :
+		 priv->default_vlan_prio;
+	int tc = netdev_get_prio_tc_map(dev, up);
+
+	return priv->channeltc_to_txq_map[channel_ix][tc];
+}
+
+static inline u16 mlx5e_get_inline_hdr_size(struct mlx5e_sq *sq,
+					    struct sk_buff *skb, bool bf)
+{
+	/* Some NIC TX decisions, e.g loopback, are based on the packet
+	 * headers and occur before the data gather.
+	 * Therefore these headers must be copied into the WQE
+	 */
+#define MLX5E_MIN_INLINE ETH_HLEN
+
+	if (bf) {
+		u16 ihs = skb_headlen(skb);
+
+		if (skb_vlan_tag_present(skb))
+			ihs += VLAN_HLEN;
+
+		if (ihs <= sq->max_inline)
+			return skb_headlen(skb);
+	}
+
+	return MLX5E_MIN_INLINE;
+}
+
+static inline void mlx5e_insert_vlan(void *start, struct sk_buff *skb, u16 ihs)
+{
+	struct vlan_ethhdr *vhdr = (struct vlan_ethhdr *)start;
+	int cpy1_sz = 2 * ETH_ALEN;
+	int cpy2_sz = ihs - cpy1_sz;
+
+	skb_copy_from_linear_data(skb, vhdr, cpy1_sz);
+	skb_pull_inline(skb, cpy1_sz);
+	vhdr->h_vlan_proto = skb->vlan_proto;
+	vhdr->h_vlan_TCI = cpu_to_be16(skb_vlan_tag_get(skb));
+	skb_copy_from_linear_data(skb, &vhdr->h_vlan_encapsulated_proto,
+				  cpy2_sz);
+	skb_pull_inline(skb, cpy2_sz);
+}
+
+static netdev_tx_t mlx5e_sq_xmit(struct mlx5e_sq *sq, struct sk_buff *skb)
+{
+	struct mlx5_wq_cyc       *wq   = &sq->wq;
+
+	u16 pi = sq->pc & wq->sz_m1;
+	struct mlx5e_tx_wqe      *wqe  = mlx5_wq_cyc_get_wqe(wq, pi);
+
+	struct mlx5_wqe_ctrl_seg *cseg = &wqe->ctrl;
+	struct mlx5_wqe_eth_seg  *eseg = &wqe->eth;
+	struct mlx5_wqe_data_seg *dseg;
+
+	u8  opcode = MLX5_OPCODE_SEND;
+	dma_addr_t dma_addr = 0;
+	bool bf = false;
+	u16 headlen;
+	u16 ds_cnt;
+	u16 ihs;
+	int i;
+
+	memset(wqe, 0, sizeof(*wqe));
+
+	if (likely(skb->ip_summed == CHECKSUM_PARTIAL))
+		eseg->cs_flags	= MLX5_ETH_WQE_L3_CSUM | MLX5_ETH_WQE_L4_CSUM;
+	else
+		sq->stats.csum_offload_none++;
+
+	if (sq->cc != sq->prev_cc) {
+		sq->prev_cc = sq->cc;
+		sq->bf_budget = (sq->cc == sq->pc) ? MLX5E_SQ_BF_BUDGET : 0;
+	}
+
+	if (skb_is_gso(skb)) {
+		u32 payload_len;
+
+		eseg->mss    = cpu_to_be16(skb_shinfo(skb)->gso_size);
+		opcode       = MLX5_OPCODE_LSO;
+		ihs          = skb_transport_offset(skb) + tcp_hdrlen(skb);
+		payload_len  = skb->len - ihs;
+		MLX5E_TX_SKB_CB(skb)->num_bytes = skb->len +
+					(skb_shinfo(skb)->gso_segs - 1) * ihs;
+		sq->stats.tso_packets++;
+		sq->stats.tso_bytes += payload_len;
+	} else {
+		bf = sq->bf_budget &&
+		     !skb->xmit_more &&
+		     !skb_shinfo(skb)->nr_frags;
+		ihs = mlx5e_get_inline_hdr_size(sq, skb, bf);
+		MLX5E_TX_SKB_CB(skb)->num_bytes = max_t(unsigned int, skb->len,
+							ETH_ZLEN);
+	}
+
+	if (skb_vlan_tag_present(skb)) {
+		mlx5e_insert_vlan(eseg->inline_hdr_start, skb, ihs);
+		ihs += VLAN_HLEN;
+	} else {
+		skb_copy_from_linear_data(skb, eseg->inline_hdr_start, ihs);
+		skb_pull_inline(skb, ihs);
+	}
+
+	eseg->inline_hdr_sz = cpu_to_be16(ihs);
+
+	ds_cnt  = sizeof(*wqe) / MLX5_SEND_WQE_DS;
+	ds_cnt += DIV_ROUND_UP(ihs - sizeof(eseg->inline_hdr_start),
+			       MLX5_SEND_WQE_DS);
+	dseg    = (struct mlx5_wqe_data_seg *)cseg + ds_cnt;
+
+	MLX5E_TX_SKB_CB(skb)->num_dma = 0;
+
+	headlen = skb_headlen(skb);
+	if (headlen) {
+		dma_addr = dma_map_single(sq->pdev, skb->data, headlen,
+					  DMA_TO_DEVICE);
+		if (unlikely(dma_mapping_error(sq->pdev, dma_addr)))
+			goto dma_unmap_wqe_err;
+
+		dseg->addr       = cpu_to_be64(dma_addr);
+		dseg->lkey       = sq->mkey_be;
+		dseg->byte_count = cpu_to_be32(headlen);
+
+		mlx5e_dma_push(sq, dma_addr, headlen, MLX5E_DMA_MAP_SINGLE);
+		MLX5E_TX_SKB_CB(skb)->num_dma++;
+
+		dseg++;
+	}
+
+	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
+		struct skb_frag_struct *frag = &skb_shinfo(skb)->frags[i];
+		int fsz = skb_frag_size(frag);
+
+		dma_addr = skb_frag_dma_map(sq->pdev, frag, 0, fsz,
+					    DMA_TO_DEVICE);
+		if (unlikely(dma_mapping_error(sq->pdev, dma_addr)))
+			goto dma_unmap_wqe_err;
+
+		dseg->addr       = cpu_to_be64(dma_addr);
+		dseg->lkey       = sq->mkey_be;
+		dseg->byte_count = cpu_to_be32(fsz);
+
+		mlx5e_dma_push(sq, dma_addr, fsz, MLX5E_DMA_MAP_PAGE);
+		MLX5E_TX_SKB_CB(skb)->num_dma++;
+
+		dseg++;
+	}
+
+	ds_cnt += MLX5E_TX_SKB_CB(skb)->num_dma;
+
+	cseg->opmod_idx_opcode = cpu_to_be32((sq->pc << 8) | opcode);
+	cseg->qpn_ds           = cpu_to_be32((sq->sqn << 8) | ds_cnt);
+
+	sq->skb[pi] = skb;
+
+	MLX5E_TX_SKB_CB(skb)->num_wqebbs = DIV_ROUND_UP(ds_cnt,
+							MLX5_SEND_WQEBB_NUM_DS);
+	sq->pc += MLX5E_TX_SKB_CB(skb)->num_wqebbs;
+
+	netdev_tx_sent_queue(sq->txq, MLX5E_TX_SKB_CB(skb)->num_bytes);
+
+	if (unlikely(!mlx5e_sq_has_room_for(sq, MLX5E_SQ_STOP_ROOM))) {
+		netif_tx_stop_queue(sq->txq);
+		sq->stats.stopped++;
+	}
+
+	if (!skb->xmit_more || netif_xmit_stopped(sq->txq)) {
+		int bf_sz = 0;
+
+		if (bf && sq->uar_bf_map)
+			bf_sz = MLX5E_TX_SKB_CB(skb)->num_wqebbs << 3;
+
+		cseg->fm_ce_se = MLX5_WQE_CTRL_CQ_UPDATE;
+		mlx5e_tx_notify_hw(sq, wqe, bf_sz);
+	}
+
+	/* fill sq edge with nops to avoid wqe wrap around */
+	while ((sq->pc & wq->sz_m1) > sq->edge)
+		mlx5e_send_nop(sq, false);
+
+	sq->bf_budget = bf ? sq->bf_budget - 1 : 0;
+
+	sq->stats.packets++;
+	return NETDEV_TX_OK;
+
+dma_unmap_wqe_err:
+	sq->stats.dropped++;
+	mlx5e_dma_unmap_wqe_err(sq, skb);
+
+	dev_kfree_skb_any(skb);
+
+	return NETDEV_TX_OK;
+}
+
+netdev_tx_t mlx5e_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct mlx5e_priv *priv = netdev_priv(dev);
+	struct mlx5e_sq *sq = priv->txq_to_sq_map[skb_get_queue_mapping(skb)];
+
+	return mlx5e_sq_xmit(sq, skb);
+}
+
+bool mlx5e_poll_tx_cq(struct mlx5e_cq *cq)
+{
+	struct mlx5e_sq *sq;
+	u32 dma_fifo_cc;
+	u32 nbytes;
+	u16 npkts;
+	u16 sqcc;
+	int i;
+
+	/* avoid accessing cq (dma coherent memory) if not needed */
+	if (!test_and_clear_bit(MLX5E_CQ_HAS_CQES, &cq->flags))
+		return false;
+
+	sq = container_of(cq, struct mlx5e_sq, cq);
+
+	npkts = 0;
+	nbytes = 0;
+
+	/* sq->cc must be updated only after mlx5_cqwq_update_db_record(),
+	 * otherwise a cq overrun may occur
+	 */
+	sqcc = sq->cc;
+
+	/* avoid dirtying sq cache line every cqe */
+	dma_fifo_cc = sq->dma_fifo_cc;
+
+	for (i = 0; i < MLX5E_TX_CQ_POLL_BUDGET; i++) {
+		struct mlx5_cqe64 *cqe;
+		u16 wqe_counter;
+		bool last_wqe;
+
+		cqe = mlx5e_get_cqe(cq);
+		if (!cqe)
+			break;
+
+		mlx5_cqwq_pop(&cq->wq);
+
+		wqe_counter = be16_to_cpu(cqe->wqe_counter);
+
+		do {
+			struct sk_buff *skb;
+			u16 ci;
+			int j;
+
+			last_wqe = (sqcc == wqe_counter);
+
+			ci = sqcc & sq->wq.sz_m1;
+			skb = sq->skb[ci];
+
+			if (unlikely(!skb)) { /* nop */
+				sq->stats.nop++;
+				sqcc++;
+				continue;
+			}
+
+			for (j = 0; j < MLX5E_TX_SKB_CB(skb)->num_dma; j++) {
+				struct mlx5e_sq_dma *dma =
+					mlx5e_dma_get(sq, dma_fifo_cc++);
+
+				mlx5e_tx_dma_unmap(sq->pdev, dma);
+			}
+
+			npkts++;
+			nbytes += MLX5E_TX_SKB_CB(skb)->num_bytes;
+			sqcc += MLX5E_TX_SKB_CB(skb)->num_wqebbs;
+			dev_kfree_skb(skb);
+		} while (!last_wqe);
+	}
+
+	mlx5_cqwq_update_db_record(&cq->wq);
+
+	/* ensure cq space is freed before enabling more cqes */
+	wmb();
+
+	sq->dma_fifo_cc = dma_fifo_cc;
+	sq->cc = sqcc;
+
+	netdev_tx_completed_queue(sq->txq, npkts, nbytes);
+
+	if (netif_tx_queue_stopped(sq->txq) &&
+	    mlx5e_sq_has_room_for(sq, MLX5E_SQ_STOP_ROOM) &&
+	    likely(test_bit(MLX5E_SQ_STATE_WAKE_TXQ_ENABLE, &sq->state))) {
+				netif_tx_wake_queue(sq->txq);
+				sq->stats.wake++;
+	}
+	if (i == MLX5E_TX_CQ_POLL_BUDGET) {
+		set_bit(MLX5E_CQ_HAS_CQES, &cq->flags);
+		return true;
+	}
+
+	return false;
+}