[dpdk-dev] [PATCH v6 3/5] net/mlx4: restore Tx checksum offloads

[Adrien Mazarguil <adrien.mazarguil@6wind.com>]

From: Moti Haimovsky <motih@mellanox.com>

This patch adds hardware offloading support for IPv4, UDP and TCP checksum
calculation, including inner/outer checksums on supported tunnel types.

Signed-off-by: Moti Haimovsky <motih@mellanox.com>
Acked-by: Adrien Mazarguil <adrien.mazarguil@6wind.com>
---
 doc/guides/nics/features/mlx4.ini |  4 ++++
 drivers/net/mlx4/mlx4.c           | 11 +++++++++++
 drivers/net/mlx4/mlx4.h           |  2 ++
 drivers/net/mlx4/mlx4_ethdev.c    |  6 ++++++
 drivers/net/mlx4/mlx4_prm.h       |  2 ++
 drivers/net/mlx4/mlx4_rxtx.c      | 19 +++++++++++++++++++
 drivers/net/mlx4/mlx4_rxtx.h      |  2 ++
 drivers/net/mlx4/mlx4_txq.c       |  2 ++
 8 files changed, 48 insertions(+)

diff --git a/doc/guides/nics/features/mlx4.ini b/doc/guides/nics/features/mlx4.ini
index 19ae688..366e051 100644
--- a/doc/guides/nics/features/mlx4.ini
+++ b/doc/guides/nics/features/mlx4.ini
@@ -20,6 +20,10 @@ Multicast MAC filter = Y
 RSS hash             = Y
 SR-IOV               = Y
 VLAN filter          = Y
+L3 checksum offload  = Y
+L4 checksum offload  = Y
+Inner L3 checksum    = Y
+Inner L4 checksum    = Y
 Basic stats          = Y
 Stats per queue      = Y
 Other kdrv           = Y
diff --git a/drivers/net/mlx4/mlx4.c b/drivers/net/mlx4/mlx4.c
index 0db9a19..a297b9a 100644
--- a/drivers/net/mlx4/mlx4.c
+++ b/drivers/net/mlx4/mlx4.c
@@ -566,6 +566,17 @@ mlx4_pci_probe(struct rte_pci_driver *pci_drv, struct rte_pci_device *pci_dev)
 		priv->pd = pd;
 		priv->mtu = ETHER_MTU;
 		priv->vf = vf;
+		priv->hw_csum =	!!(device_attr.device_cap_flags &
+				   IBV_DEVICE_RAW_IP_CSUM);
+		DEBUG("checksum offloading is %ssupported",
+		      (priv->hw_csum ? "" : "not "));
+		/* Only ConnectX-3 Pro supports tunneling. */
+		priv->hw_csum_l2tun =
+			priv->hw_csum &&
+			(device_attr.vendor_part_id ==
+			 PCI_DEVICE_ID_MELLANOX_CONNECTX3PRO);
+		DEBUG("L2 tunnel checksum offloads are %ssupported",
+		      (priv->hw_csum_l2tun ? "" : "not "));
 		/* Configure the first MAC address by default. */
 		if (mlx4_get_mac(priv, &mac.addr_bytes)) {
 			ERROR("cannot get MAC address, is mlx4_en loaded?"
diff --git a/drivers/net/mlx4/mlx4.h b/drivers/net/mlx4/mlx4.h
index f4da8c6..e0a9853 100644
--- a/drivers/net/mlx4/mlx4.h
+++ b/drivers/net/mlx4/mlx4.h
@@ -113,6 +113,8 @@ struct priv {
 	uint32_t vf:1; /**< This is a VF device. */
 	uint32_t intr_alarm:1; /**< An interrupt alarm is scheduled. */
 	uint32_t isolated:1; /**< Toggle isolated mode. */
+	uint32_t hw_csum:1; /* Checksum offload is supported. */
+	uint32_t hw_csum_l2tun:1; /* Checksum support for L2 tunnels. */
 	struct rte_intr_handle intr_handle; /**< Port interrupt handle. */
 	struct mlx4_drop *drop; /**< Shared resources for drop flow rules. */
 	LIST_HEAD(, mlx4_rss) rss; /**< Shared targets for Rx flow rules. */
diff --git a/drivers/net/mlx4/mlx4_ethdev.c b/drivers/net/mlx4/mlx4_ethdev.c
index 3623909..a8c0ee2 100644
--- a/drivers/net/mlx4/mlx4_ethdev.c
+++ b/drivers/net/mlx4/mlx4_ethdev.c
@@ -767,6 +767,12 @@ mlx4_dev_infos_get(struct rte_eth_dev *dev, struct rte_eth_dev_info *info)
 	info->max_mac_addrs = RTE_DIM(priv->mac);
 	info->rx_offload_capa = 0;
 	info->tx_offload_capa = 0;
+	if (priv->hw_csum)
+		info->tx_offload_capa |= (DEV_TX_OFFLOAD_IPV4_CKSUM |
+					  DEV_TX_OFFLOAD_UDP_CKSUM |
+					  DEV_TX_OFFLOAD_TCP_CKSUM);
+	if (priv->hw_csum_l2tun)
+		info->tx_offload_capa |= DEV_TX_OFFLOAD_OUTER_IPV4_CKSUM;
 	if (mlx4_get_ifname(priv, &ifname) == 0)
 		info->if_index = if_nametoindex(ifname);
 	info->hash_key_size = MLX4_RSS_HASH_KEY_SIZE;
diff --git a/drivers/net/mlx4/mlx4_prm.h b/drivers/net/mlx4/mlx4_prm.h
index 085a595..df5a6b4 100644
--- a/drivers/net/mlx4/mlx4_prm.h
+++ b/drivers/net/mlx4/mlx4_prm.h
@@ -64,6 +64,8 @@
 
 /* Work queue element (WQE) flags. */
 #define MLX4_BIT_WQE_OWN 0x80000000
+#define MLX4_WQE_CTRL_IIP_HDR_CSUM (1 << 28)
+#define MLX4_WQE_CTRL_IL4_HDR_CSUM (1 << 27)
 
 #define MLX4_SIZE_TO_TXBBS(size) \
 	(RTE_ALIGN((size), (MLX4_TXBB_SIZE)) >> (MLX4_TXBB_SHIFT))
diff --git a/drivers/net/mlx4/mlx4_rxtx.c b/drivers/net/mlx4/mlx4_rxtx.c
index cc0baaa..fe7d5d0 100644
--- a/drivers/net/mlx4/mlx4_rxtx.c
+++ b/drivers/net/mlx4/mlx4_rxtx.c
@@ -431,6 +431,25 @@ mlx4_post_send(struct txq *txq, struct rte_mbuf *pkt)
 	} else {
 		srcrb_flags = RTE_BE32(MLX4_WQE_CTRL_SOLICIT);
 	}
+	/* Enable HW checksum offload if requested */
+	if (txq->csum &&
+	    (pkt->ol_flags &
+	     (PKT_TX_IP_CKSUM | PKT_TX_TCP_CKSUM | PKT_TX_UDP_CKSUM))) {
+		const uint64_t is_tunneled = (pkt->ol_flags &
+					      (PKT_TX_TUNNEL_GRE |
+					       PKT_TX_TUNNEL_VXLAN));
+
+		if (is_tunneled && txq->csum_l2tun) {
+			owner_opcode |= MLX4_WQE_CTRL_IIP_HDR_CSUM |
+					MLX4_WQE_CTRL_IL4_HDR_CSUM;
+			if (pkt->ol_flags & PKT_TX_OUTER_IP_CKSUM)
+				srcrb_flags |=
+					RTE_BE32(MLX4_WQE_CTRL_IP_HDR_CSUM);
+		} else {
+			srcrb_flags |= RTE_BE32(MLX4_WQE_CTRL_IP_HDR_CSUM |
+						MLX4_WQE_CTRL_TCP_UDP_CSUM);
+		}
+	}
 	ctrl->srcrb_flags = srcrb_flags;
 	/*
 	 * Make sure descriptor is fully written before
diff --git a/drivers/net/mlx4/mlx4_rxtx.h b/drivers/net/mlx4/mlx4_rxtx.h
index fa5738f..6c88efb 100644
--- a/drivers/net/mlx4/mlx4_rxtx.h
+++ b/drivers/net/mlx4/mlx4_rxtx.h
@@ -124,6 +124,8 @@ struct txq {
 	struct txq_elt (*elts)[]; /**< Tx elements. */
 	struct mlx4_txq_stats stats; /**< Tx queue counters. */
 	uint32_t max_inline; /**< Max inline send size. */
+	uint32_t csum:1; /**< Enable checksum offloading. */
+	uint32_t csum_l2tun:1; /**< Same for L2 tunnels. */
 	uint8_t *bounce_buf;
 	/**< Memory used for storing the first DWORD of data TXBBs. */
 	struct {
diff --git a/drivers/net/mlx4/mlx4_txq.c b/drivers/net/mlx4/mlx4_txq.c
index fbb028a..0e27df2 100644
--- a/drivers/net/mlx4/mlx4_txq.c
+++ b/drivers/net/mlx4/mlx4_txq.c
@@ -276,6 +276,8 @@ mlx4_tx_queue_setup(struct rte_eth_dev *dev, uint16_t idx, uint16_t desc,
 			RTE_MIN(MLX4_PMD_TX_PER_COMP_REQ, desc / 4),
 		.elts_comp_cd_init =
 			RTE_MIN(MLX4_PMD_TX_PER_COMP_REQ, desc / 4),
+		.csum = priv->hw_csum,
+		.csum_l2tun = priv->hw_csum_l2tun,
 		.bounce_buf = bounce_buf,
 	};
 	txq->cq = ibv_create_cq(priv->ctx, desc, NULL, NULL, 0);
-- 
2.1.4