[PATCH 6/8] net/i40e: fix outer UDP checksum offload for X710

[David Marchand]

According to the X710 datasheet (and confirmed on the field..), X710
devices do not support outer checksum offload.

"""
8.4.4.2 Transmit L3 and L4 Integrity Offload

Tunneling UDP headers and GRE header are not offloaded while the
X710/XXV710/XL710 leaves their checksum field as is.
If a checksum is required, software should provide it as well as the inner
checksum value(s) that are required for the outer checksum.
"""

Fix Tx offload capabilities according to the hardware.

X722 may support such offload by setting I40E_TXD_CTX_QW0_L4T_CS_MASK.

Bugzilla ID: 1406
Fixes: 8cc79a1636cd ("net/i40e: fix forward outer IPv6 VXLAN")
Cc: stable at dpdk.org

Reported-by: Jun Wang <junwang01 at cestc.cn>
Signed-off-by: David Marchand <david.marchand at redhat.com>
---
Note: I do not have X722 nic. Please Intel devs, check for both X710 and
X722 series.

---
 .mailmap                       | 1 +
 drivers/net/i40e/i40e_ethdev.c | 6 +++++-
 drivers/net/i40e/i40e_rxtx.c   | 9 +++++++++
 3 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/.mailmap b/.mailmap
index 3843868716..091766eca7 100644
--- a/.mailmap
+++ b/.mailmap
@@ -719,6 +719,7 @@ Junjie Wan <wanjunjie at bytedance.com>
 Jun Qiu <jun.qiu at jaguarmicro.com>
 Jun W Zhou <junx.w.zhou at intel.com>
 Junxiao Shi <git at mail1.yoursunny.com>
+Jun Wang <junwang01 at cestc.cn>
 Jun Yang <jun.yang at nxp.com>
 Junyu Jiang <junyux.jiang at intel.com>
 Juraj Linkeš <juraj.linkes at pantheon.tech>
diff --git a/drivers/net/i40e/i40e_ethdev.c b/drivers/net/i40e/i40e_ethdev.c
index 380ce1a720..6535c7c178 100644
--- a/drivers/net/i40e/i40e_ethdev.c
+++ b/drivers/net/i40e/i40e_ethdev.c
@@ -3862,8 +3862,12 @@ i40e_dev_info_get(struct rte_eth_dev *dev, struct rte_eth_dev_info *dev_info)
 		RTE_ETH_TX_OFFLOAD_IPIP_TNL_TSO |
 		RTE_ETH_TX_OFFLOAD_GENEVE_TNL_TSO |
 		RTE_ETH_TX_OFFLOAD_MULTI_SEGS |
-		RTE_ETH_TX_OFFLOAD_OUTER_UDP_CKSUM |
 		dev_info->tx_queue_offload_capa;
+	if (hw->mac.type == I40E_MAC_X722) {
+		dev_info->tx_offload_capa |=
+			RTE_ETH_TX_OFFLOAD_OUTER_UDP_CKSUM;
+	}
+
 	dev_info->dev_capa =
 		RTE_ETH_DEV_CAPA_RUNTIME_RX_QUEUE_SETUP |
 		RTE_ETH_DEV_CAPA_RUNTIME_TX_QUEUE_SETUP;
diff --git a/drivers/net/i40e/i40e_rxtx.c b/drivers/net/i40e/i40e_rxtx.c
index 5d25ab4d3a..a649911494 100644
--- a/drivers/net/i40e/i40e_rxtx.c
+++ b/drivers/net/i40e/i40e_rxtx.c
@@ -295,6 +295,15 @@ i40e_parse_tunneling_params(uint64_t ol_flags,
 	 */
 	*cd_tunneling |= (tx_offload.l2_len >> 1) <<
 		I40E_TXD_CTX_QW0_NATLEN_SHIFT;
+
+	/**
+	 * Calculate the tunneling UDP checksum (only supported with X722).
+	 * Shall be set only if L4TUNT = 01b and EIPT is not zero
+	 */
+	if (!(*cd_tunneling & I40E_TXD_CTX_QW0_EXT_IP_MASK) &&
+		(*cd_tunneling & I40E_TXD_CTX_UDP_TUNNELING) &&
+		(ol_flags & RTE_MBUF_F_TX_OUTER_UDP_CKSUM))
+		*cd_tunneling |= I40E_TXD_CTX_QW0_L4T_CS_MASK;
 }
 
 static inline void
-- 
2.44.0