[RFC PATCH 15/27] net/intel: support configurable VLAN tag insertion on Tx

Bruce Richardson
2025-12-19T17:27:57Z

Make the VLAN tag insertion logic configurable in the common code, as to
where inner/outer tags get placed.

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
---
drivers/net/intel/common/tx.h | 10 ++++++++++
drivers/net/intel/common/tx_scalar_fns.h | 9 +++++++--
drivers/net/intel/i40e/i40e_rxtx.c | 4 ++--
drivers/net/intel/ice/ice_rxtx.c | 4 ++--
4 files changed, 21 insertions(+), 6 deletions(-)

diff --git a/drivers/net/intel/common/tx.h b/drivers/net/intel/common/tx.h
index a71b98f119..0d11daaab3 100644
--- a/drivers/net/intel/common/tx.h
+++ b/drivers/net/intel/common/tx.h
@@ -45,6 +45,16 @@
#define CI_TX_CTX_DESC_TSYN 0x02
#define CI_TX_CTX_DESC_IL2TAG2 0x04

+/**
+ * L2TAG1 Field Source Selection
+ * Specifies which mbuf VLAN field to use for the L2TAG1 field in data descriptors.
+ * Context descriptor VLAN handling (L2TAG2) is managed by driver-specific callbacks.
+ */
+enum ci_tx_l2tag1_field {
+ CI_VLAN_IN_L2TAG1, /**< For VLAN (not QinQ), use L2Tag1 field in data desc */
+ CI_VLAN_IN_L2TAG2, /**< For VLAN (not QinQ), use L2Tag2 field in ctx desc */
+};
+
/* Common TX Descriptor Length Field Shifts */
#define CI_TX_DESC_LEN_MACLEN_S 0 /* 7 BITS */
#define CI_TX_DESC_LEN_IPLEN_S 7 /* 7 BITS */
diff --git a/drivers/net/intel/common/tx_scalar_fns.h b/drivers/net/intel/common/tx_scalar_fns.h
index 8c0de26537..6079a558e4 100644
--- a/drivers/net/intel/common/tx_scalar_fns.h
+++ b/drivers/net/intel/common/tx_scalar_fns.h
@@ -188,6 +188,7 @@ static inline uint16_t
ci_xmit_pkts(struct ci_tx_queue *txq,
struct rte_mbuf **tx_pkts,
uint16_t nb_pkts,
+ enum ci_tx_l2tag1_field l2tag1_field,
ci_get_ctx_desc_fn get_ctx_desc,
const struct ci_ipsec_ops *ipsec_ops,
const struct ci_timesstamp_queue_fns *ts_fns)
@@ -286,8 +287,12 @@ ci_xmit_pkts(struct ci_tx_queue *txq,
}
}

- /* Descriptor based VLAN insertion */
- if (ol_flags & (RTE_MBUF_F_TX_VLAN | RTE_MBUF_F_TX_QINQ)) {
+ /* Descriptor based VLAN/QinQ insertion */
+ /* for single vlan offload, only insert in data desc with VLAN_IN_L2TAG1 is set
+ * for qinq offload, we always put inner tag in L2Tag1
+ */
+ if (((ol_flags & RTE_MBUF_F_TX_VLAN) && (l2tag1_field == CI_VLAN_IN_L2TAG1)) ||
+ (ol_flags & RTE_MBUF_F_TX_QINQ)) {
td_cmd |= CI_TX_DESC_CMD_IL2TAG1;
td_tag = tx_pkt->vlan_tci;
}
diff --git a/drivers/net/intel/i40e/i40e_rxtx.c b/drivers/net/intel/i40e/i40e_rxtx.c
index e22fcfff60..2d12e6dd1a 100644
--- a/drivers/net/intel/i40e/i40e_rxtx.c
+++ b/drivers/net/intel/i40e/i40e_rxtx.c
@@ -1002,7 +1002,7 @@ get_context_desc(uint64_t ol_flags, const struct rte_mbuf *tx_pkt,
/* TX context descriptor based double VLAN insert */
if (ol_flags & RTE_MBUF_F_TX_QINQ) {
cd_l2tag2 = tx_pkt->vlan_tci_outer;
- cd_type_cmd_tso_mss |= ((uint64_t)I40E_TX_CTX_DESC_IL2TAG2 << I40E_TXD_CTX_QW1_CMD_SHIFT);
+ cd_type_cmd_tso_mss |= (I40E_TX_CTX_DESC_IL2TAG2 << I40E_TXD_CTX_QW1_CMD_SHIFT);
}

*qw0 = rte_cpu_to_le_32(cd_tunneling_params) |
@@ -1016,7 +1016,7 @@ uint16_t
i40e_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
{
/* i40e does not support IPsec or timestamp queues, so pass NULL for both */
- return ci_xmit_pkts(tx_queue, tx_pkts, nb_pkts, get_context_desc, NULL, NULL);
+ return ci_xmit_pkts(tx_queue, tx_pkts, nb_pkts, CI_VLAN_IN_L2TAG1, get_context_desc, NULL, NULL);
}

static __rte_always_inline int
diff --git a/drivers/net/intel/ice/ice_rxtx.c b/drivers/net/intel/ice/ice_rxtx.c
index 49ed6b8399..2c73011181 100644
--- a/drivers/net/intel/ice/ice_rxtx.c
+++ b/drivers/net/intel/ice/ice_rxtx.c
@@ -3100,9 +3100,9 @@ ice_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
struct ci_tx_queue *txq = (struct ci_tx_queue *)tx_queue;

if (txq->tsq != NULL && txq->tsq->ts_flag > 0)
- return ci_xmit_pkts(txq, tx_pkts, nb_pkts, get_context_desc, NULL, &ts_fns);
+ return ci_xmit_pkts(txq, tx_pkts, nb_pkts, CI_VLAN_IN_L2TAG1, get_context_desc, NULL, &ts_fns);

- return ci_xmit_pkts(txq, tx_pkts, nb_pkts, get_context_desc, NULL, NULL);
+ return ci_xmit_pkts(txq, tx_pkts, nb_pkts, CI_VLAN_IN_L2TAG1, get_context_desc, NULL, NULL);
}

static __rte_always_inline int
--
2.51.0