[PATCH v2 1/6] net/mlx5: sample the srv6 last segment

[Rongwei Liu <rongweil@nvidia.com>]

When removing the IPv6 routing extension header from the
packets, the destination address should be updated to the
last one in the segment list.

Enlarge the hardware sample scope to cover the last segment.

Signed-off-by: Rongwei Liu <rongweil@nvidia.com>
Acked-by: Ori Kam <orika@nvidia.com>
Acked-by: Suanming Mou <suanmingm@nvidia.com>
---
 drivers/net/mlx5/mlx5.c | 41 ++++++++++++++++++++++++++++++-----------
 drivers/net/mlx5/mlx5.h |  6 ++++++
 2 files changed, 36 insertions(+), 11 deletions(-)

diff --git a/drivers/net/mlx5/mlx5.c b/drivers/net/mlx5/mlx5.c
index f929d6547c..92d66e8f23 100644
--- a/drivers/net/mlx5/mlx5.c
+++ b/drivers/net/mlx5/mlx5.c
@@ -1067,6 +1067,7 @@ mlx5_alloc_srh_flex_parser(struct rte_eth_dev *dev)
 	struct mlx5_devx_graph_node_attr node = {
 		.modify_field_select = 0,
 	};
+	uint32_t i;
 	uint32_t ids[MLX5_GRAPH_NODE_SAMPLE_NUM];
 	struct mlx5_priv *priv = dev->data->dev_private;
 	struct mlx5_common_dev_config *config = &priv->sh->cdev->config;
@@ -1100,10 +1101,18 @@ mlx5_alloc_srh_flex_parser(struct rte_eth_dev *dev)
 	node.next_header_field_size = 0x8;
 	node.in[0].arc_parse_graph_node = MLX5_GRAPH_ARC_NODE_IP;
 	node.in[0].compare_condition_value = IPPROTO_ROUTING;
-	node.sample[0].flow_match_sample_en = 1;
-	/* First come first serve no matter inner or outer. */
-	node.sample[0].flow_match_sample_tunnel_mode = MLX5_GRAPH_SAMPLE_TUNNEL_FIRST;
-	node.sample[0].flow_match_sample_offset_mode = MLX5_GRAPH_SAMPLE_OFFSET_FIXED;
+	/* Final IPv6 address. */
+	for (i = 0; i <= MLX5_SRV6_SAMPLE_NUM - 1 && i < MLX5_GRAPH_NODE_SAMPLE_NUM; i++) {
+		node.sample[i].flow_match_sample_en = 1;
+		node.sample[i].flow_match_sample_offset_mode =
+					MLX5_GRAPH_SAMPLE_OFFSET_FIXED;
+		/* First come first serve no matter inner or outer. */
+		node.sample[i].flow_match_sample_tunnel_mode =
+					MLX5_GRAPH_SAMPLE_TUNNEL_FIRST;
+		node.sample[i].flow_match_sample_field_base_offset =
+					(i + 1) * sizeof(uint32_t); /* in bytes */
+	}
+	node.sample[0].flow_match_sample_field_base_offset = 0;
 	node.out[0].arc_parse_graph_node = MLX5_GRAPH_ARC_NODE_TCP;
 	node.out[0].compare_condition_value = IPPROTO_TCP;
 	node.out[1].arc_parse_graph_node = MLX5_GRAPH_ARC_NODE_UDP;
@@ -1116,8 +1125,8 @@ mlx5_alloc_srh_flex_parser(struct rte_eth_dev *dev)
 		goto error;
 	}
 	priv->sh->srh_flex_parser.flex.devx_fp->devx_obj = fp;
-	priv->sh->srh_flex_parser.flex.mapnum = 1;
-	priv->sh->srh_flex_parser.flex.devx_fp->num_samples = 1;
+	priv->sh->srh_flex_parser.flex.mapnum = MLX5_SRV6_SAMPLE_NUM;
+	priv->sh->srh_flex_parser.flex.devx_fp->num_samples = MLX5_SRV6_SAMPLE_NUM;
 
 	ret = mlx5_devx_cmd_query_parse_samples(fp, ids, priv->sh->srh_flex_parser.flex.mapnum,
 						&priv->sh->srh_flex_parser.flex.devx_fp->anchor_id);
@@ -1125,12 +1134,22 @@ mlx5_alloc_srh_flex_parser(struct rte_eth_dev *dev)
 		DRV_LOG(ERR, "Failed to query sample IDs.");
 		goto error;
 	}
-	ret = mlx5_devx_cmd_match_sample_info_query(ibv_ctx, ids[0],
-				&priv->sh->srh_flex_parser.flex.devx_fp->sample_info[0]);
-	if (ret) {
-		DRV_LOG(ERR, "Failed to query sample id information.");
-		goto error;
+	for (i = 0; i <= MLX5_SRV6_SAMPLE_NUM - 1 && i < MLX5_GRAPH_NODE_SAMPLE_NUM; i++) {
+		ret = mlx5_devx_cmd_match_sample_info_query(ibv_ctx, ids[i],
+					&priv->sh->srh_flex_parser.flex.devx_fp->sample_info[i]);
+		if (ret) {
+			DRV_LOG(ERR, "Failed to query sample id %u information.", ids[i]);
+			goto error;
+		}
+	}
+	for (i = 0; i <= MLX5_SRV6_SAMPLE_NUM - 1 && i < MLX5_GRAPH_NODE_SAMPLE_NUM; i++) {
+		priv->sh->srh_flex_parser.flex.devx_fp->sample_ids[i] = ids[i];
+		priv->sh->srh_flex_parser.flex.map[i].width = sizeof(uint32_t) * CHAR_BIT;
+		priv->sh->srh_flex_parser.flex.map[i].reg_id = i;
+		priv->sh->srh_flex_parser.flex.map[i].shift =
+						(i + 1) * sizeof(uint32_t) * CHAR_BIT;
 	}
+	priv->sh->srh_flex_parser.flex.map[0].shift = 0;
 	return 0;
 error:
 	if (fp)
diff --git a/drivers/net/mlx5/mlx5.h b/drivers/net/mlx5/mlx5.h
index a20acb6ca8..f13a56ee9e 100644
--- a/drivers/net/mlx5/mlx5.h
+++ b/drivers/net/mlx5/mlx5.h
@@ -1335,6 +1335,7 @@ struct mlx5_flex_pattern_field {
 	uint16_t shift:5;
 	uint16_t reg_id:5;
 };
+
 #define MLX5_INVALID_SAMPLE_REG_ID 0x1F
 
 /* Port flex item context. */
@@ -1346,6 +1347,11 @@ struct mlx5_flex_item {
 	struct mlx5_flex_pattern_field map[MLX5_FLEX_ITEM_MAPPING_NUM];
 };
 
+/*
+ * Sample an IPv6 address and the first dword of SRv6 header.
+ * Then it is 16 + 4 = 20 bytes which is 5 dwords.
+ */
+#define MLX5_SRV6_SAMPLE_NUM 5
 /* Mlx5 internal flex parser profile structure. */
 struct mlx5_internal_flex_parser_profile {
 	uint32_t refcnt;
-- 
2.27.0