[PATCH V3] net/mlx5: fix IPv6 DSCP offset in HWS sync API

[Gavin Li <gavinl@nvidia.com>]

The processing of field IPv6 DSCP via the synchronous flow API is
different between software and hardware steering engines(HWS). The bit
shift handling for IPv6 DSCP was not handled in HWS, resulting in
incorrect data in the field.

To resolve this, bit shift handling should be added to HWS.

Fixes: ec1e7a5ceb69 ("net/mlx5: update IPv6 traffic class modification")
Cc: stable@dpdk.org
Signed-off-by: Gavin Li <gavinl@nvidia.com>
Acked-by: Bing Zhao <bingz@nvidia.com>
---
 drivers/net/mlx5/mlx5_flow.h    | 7 +++++++
 drivers/net/mlx5/mlx5_flow_dv.c | 6 ------
 drivers/net/mlx5/mlx5_flow_hw.c | 5 +++++
 3 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/drivers/net/mlx5/mlx5_flow.h b/drivers/net/mlx5/mlx5_flow.h
index e8b298dd1d..2bf74b47b9 100644
--- a/drivers/net/mlx5/mlx5_flow.h
+++ b/drivers/net/mlx5/mlx5_flow.h
@@ -3711,6 +3711,13 @@ flow_hw_get_ipv6_route_ext_mod_id_from_ctx(void *dr_ctx, uint8_t idx)
 #endif
 	return 0;
 }
+
+static inline bool
+mlx5_dv_modify_ipv6_traffic_class_supported(struct mlx5_priv *priv)
+{
+	return priv->sh->phdev->config.ipv6_tc_fallback == MLX5_IPV6_TC_OK;
+}
+
 void
 mlx5_indirect_list_handles_release(struct rte_eth_dev *dev);
 
diff --git a/drivers/net/mlx5/mlx5_flow_dv.c b/drivers/net/mlx5/mlx5_flow_dv.c
index 95ca57e8c4..83046418c4 100644
--- a/drivers/net/mlx5/mlx5_flow_dv.c
+++ b/drivers/net/mlx5/mlx5_flow_dv.c
@@ -1638,12 +1638,6 @@ mlx5_modify_flex_item(const struct rte_eth_dev *dev,
 	}
 }
 
-static inline bool
-mlx5_dv_modify_ipv6_traffic_class_supported(struct mlx5_priv *priv)
-{
-	return priv->sh->phdev->config.ipv6_tc_fallback == MLX5_IPV6_TC_OK;
-}
-
 void
 mlx5_flow_field_id_to_modify_info
 		(const struct rte_flow_field_data *data,
diff --git a/drivers/net/mlx5/mlx5_flow_hw.c b/drivers/net/mlx5/mlx5_flow_hw.c
index 208f50fbfd..d3d2272338 100644
--- a/drivers/net/mlx5/mlx5_flow_hw.c
+++ b/drivers/net/mlx5/mlx5_flow_hw.c
@@ -1629,6 +1629,11 @@ flow_hw_modify_field_compile(struct rte_eth_dev *dev,
 			value = *(const uint8_t *)item.spec << 24;
 			value = rte_cpu_to_be_32(value);
 			item.spec = &value;
+		} else if (conf->dst.field == RTE_FLOW_FIELD_IPV6_DSCP &&
+			   !(mask[0] & MLX5_IPV6_HDR_ECN_MASK) &&
+			   mlx5_dv_modify_ipv6_traffic_class_supported(dev->data->dev_private)) {
+			value = *(const unaligned_uint32_t *)item.spec << MLX5_IPV6_HDR_DSCP_SHIFT;
+			item.spec = &value;
 		}
 	} else {
 		type = conf->operation == RTE_FLOW_MODIFY_SET ?
-- 
2.34.1