[dpdk-dev] [PATCH] net/e1000: i350 VLAN tags in loopback packets are big endian

[Roger B Melton]

When copying VLAN tags from the RX descriptor to the vlan_tci field in the
mbuf header,  igb_rxtx.c:eth_igb_recv_pkts() and
eth_igb_recv_scattered_pkts() both assume that the VLAN tag is always
little endian.  While i350 VLAN non-loopback packets are stored
little endian, VLAN tags for i350 VLAN loopback packets are big endian.

For i350 VLAN loopback packets, swap the tag when copying from the
RX descriptor to the mbuf header.  This will ensure that the mbuf
vlan_tci is always little endian.

Signed-off-by: Roger B Melton <rmelton at cisco.com>
---
 drivers/net/e1000/igb_rxtx.c | 56 ++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 51 insertions(+), 5 deletions(-)

diff --git a/drivers/net/e1000/igb_rxtx.c b/drivers/net/e1000/igb_rxtx.c
index 1c80a2a..8432d8b 100644
--- a/drivers/net/e1000/igb_rxtx.c
+++ b/drivers/net/e1000/igb_rxtx.c
@@ -105,6 +105,13 @@ struct igb_tx_entry {
 };
 
 /**
+ * rx queue flags
+ */
+enum igb_rxq_flags {
+	IGB_RXQ_FLAG_LB_BSWAP_VLAN = 0x01,
+};
+
+/**
  * Structure associated with each RX queue.
  */
 struct igb_rx_queue {
@@ -128,6 +135,7 @@ struct igb_rx_queue {
 	uint8_t             wthresh;    /**< Write-back threshold register. */
 	uint8_t             crc_len;    /**< 0 if CRC stripped, 4 otherwise. */
 	uint8_t             drop_en;  /**< If not 0, set SRRCTL.Drop_En. */
+	uint32_t            flags;      /**< RX flags. */
 };
 
 /**
@@ -946,9 +954,16 @@ eth_igb_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
 
 		rxm->hash.rss = rxd.wb.lower.hi_dword.rss;
 		hlen_type_rss = rte_le_to_cpu_32(rxd.wb.lower.lo_dword.data);
-		/* Only valid if PKT_RX_VLAN_PKT set in pkt_flags */
-		rxm->vlan_tci = rte_le_to_cpu_16(rxd.wb.upper.vlan);
-
+		/*
+		 * The vlan_tci field is only valid when PKT_RX_VLAN_PKT is
+		 * set in the pkt_flags field and must be in CPU byte order.
+		 */
+		if ((staterr & rte_cpu_to_le_32(E1000_RXDEXT_STATERR_LB)) &&
+			(rxq->flags & IGB_RXQ_FLAG_LB_BSWAP_VLAN)) {
+			rxm->vlan_tci = rte_be_to_cpu_16(rxd.wb.upper.vlan);
+		} else {
+			rxm->vlan_tci = rte_le_to_cpu_16(rxd.wb.upper.vlan);
+		}
 		pkt_flags = rx_desc_hlen_type_rss_to_pkt_flags(rxq, hlen_type_rss);
 		pkt_flags = pkt_flags | rx_desc_status_to_pkt_flags(staterr);
 		pkt_flags = pkt_flags | rx_desc_error_to_pkt_flags(staterr);
@@ -1181,9 +1196,16 @@ eth_igb_recv_scattered_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
 
 		/*
 		 * The vlan_tci field is only valid when PKT_RX_VLAN_PKT is
-		 * set in the pkt_flags field.
+		 * set in the pkt_flags field and must be in CPU byte order.
 		 */
-		first_seg->vlan_tci = rte_le_to_cpu_16(rxd.wb.upper.vlan);
+		if ((staterr & rte_cpu_to_le_32(E1000_RXDEXT_STATERR_LB)) &&
+			(rxq->flags & IGB_RXQ_FLAG_LB_BSWAP_VLAN)) {
+			first_seg->vlan_tci =
+				rte_be_to_cpu_16(rxd.wb.upper.vlan);
+		} else {
+			first_seg->vlan_tci =
+				rte_le_to_cpu_16(rxd.wb.upper.vlan);
+		}
 		hlen_type_rss = rte_le_to_cpu_32(rxd.wb.lower.lo_dword.data);
 		pkt_flags = rx_desc_hlen_type_rss_to_pkt_flags(rxq, hlen_type_rss);
 		pkt_flags = pkt_flags | rx_desc_status_to_pkt_flags(staterr);
@@ -2278,6 +2300,18 @@ eth_igb_rx_init(struct rte_eth_dev *dev)
 
 		rxq = dev->data->rx_queues[i];
 
+		rxq->flags = 0;
+		/*
+		 * The i210, i211, i350, i354 and i350VF LB vlan packets
+		 * have vlan tags byte swapped.
+		 */
+		if (hw->mac.type >= e1000_i350) {
+			rxq->flags |= IGB_RXQ_FLAG_LB_BSWAP_VLAN;
+			PMD_INIT_LOG(DEBUG, "IGB rx vlan bswap required");
+		} else {
+			PMD_INIT_LOG(DEBUG, "IGB rx vlan bswap not required");
+		}
+
 		/* Allocate buffers for descriptor rings and set up queue */
 		ret = igb_alloc_rx_queue_mbufs(rxq);
 		if (ret)
@@ -2557,6 +2591,18 @@ eth_igbvf_rx_init(struct rte_eth_dev *dev)
 
 		rxq = dev->data->rx_queues[i];
 
+		rxq->flags = 0;
+		/*
+		 * The i210, i211, i350, i354 and i350VF LB vlan packets
+		 * have vlan tags byte swapped.
+		 */
+		if (hw->mac.type >= e1000_i350) {
+			rxq->flags |= IGB_RXQ_FLAG_LB_BSWAP_VLAN;
+			PMD_INIT_LOG(DEBUG, "IGB rx vlan bswap required");
+		} else {
+			PMD_INIT_LOG(DEBUG, "IGB rx vlan bswap not required");
+		}
+
 		/* Allocate buffers for descriptor rings and set up queue */
 		ret = igb_alloc_rx_queue_mbufs(rxq);
 		if (ret)
-- 
2.10.3.dirty