[dpdk-stable] [PATCH] net/mlx5: fix register c0 usage for metadata entities

[Viacheslav Ovsiienko <viacheslavo@mellanox.com>]

The register c0 might be engaged to support META and MARK
related items and actions. Also, this register might be
used by kernel to specify the source vport index. The
register c0 is split into two 16-bit fields. Depending
on the mask returned by kernel the PMD can use upper
or lower half of register c0. This patch adds the missing
support for upper half.

Fixes: e554b672aa05 ("net/mlx5: support flow tag")
Cc: stable@dpdk.org

Signed-off-by: Viacheslav Ovsiienko <viacheslavo@mellanox.com>
---
 drivers/net/mlx5/mlx5_flow_dv.c | 39 +++++++++++++++++++++++++++++++++++----
 1 file changed, 35 insertions(+), 4 deletions(-)

diff --git a/drivers/net/mlx5/mlx5_flow_dv.c b/drivers/net/mlx5/mlx5_flow_dv.c
index 893db3e..f8e153c 100644
--- a/drivers/net/mlx5/mlx5_flow_dv.c
+++ b/drivers/net/mlx5/mlx5_flow_dv.c
@@ -1088,6 +1088,14 @@ struct field_modify_info modify_tcp[] = {
 	if (reg < 0)
 		return reg;
 	assert(reg > 0);
+	if (reg == REG_C_0) {
+		uint32_t msk_c0 = priv->sh->dv_regc0_mask;
+		uint32_t shl_c0 = rte_bsf32(msk_c0);
+
+		data = rte_cpu_to_be_32(rte_cpu_to_be_32(data) << shl_c0);
+		mask = rte_cpu_to_be_32(mask) & msk_c0;
+		mask = rte_cpu_to_be_32(mask << shl_c0);
+	}
 	reg_c_x[0].id = reg_to_field[reg];
 	return flow_dv_convert_modify_action(&item, reg_c_x, NULL, resource,
 					     MLX5_MODIFICATION_TYPE_SET, error);
@@ -5836,6 +5844,15 @@ struct field_modify_info modify_tcp[] = {
 		/* Get the metadata register index for the mark. */
 		reg = mlx5_flow_get_reg_id(dev, MLX5_FLOW_MARK, 0, NULL);
 		assert(reg > 0);
+		if (reg == REG_C_0) {
+			struct mlx5_priv *priv = dev->data->dev_private;
+			uint32_t msk_c0 = priv->sh->dv_regc0_mask;
+			uint32_t shl_c0 = rte_bsf32(msk_c0);
+
+			mask &= msk_c0;
+			mask <<= shl_c0;
+			value <<= shl_c0;
+		}
 		flow_dv_match_meta_reg(matcher, key, reg, value, mask);
 	}
 }
@@ -5917,6 +5934,8 @@ struct field_modify_info modify_tcp[] = {
 /**
  * Add tag item to matcher
  *
+ * @param[in] dev
+ *   The devich to configure through.
  * @param[in, out] matcher
  *   Flow matcher.
  * @param[in, out] key
@@ -5925,15 +5944,27 @@ struct field_modify_info modify_tcp[] = {
  *   Flow pattern to translate.
  */
 static void
-flow_dv_translate_mlx5_item_tag(void *matcher, void *key,
+flow_dv_translate_mlx5_item_tag(struct rte_eth_dev *dev,
+				void *matcher, void *key,
 				const struct rte_flow_item *item)
 {
 	const struct mlx5_rte_flow_item_tag *tag_v = item->spec;
 	const struct mlx5_rte_flow_item_tag *tag_m = item->mask;
+	uint32_t mask, value;
 
 	assert(tag_v);
-	flow_dv_match_meta_reg(matcher, key, tag_v->id, tag_v->data,
-			       tag_m ? tag_m->data : UINT32_MAX);
+	value = tag_v->data;
+	mask = tag_m ? tag_m->data : UINT32_MAX;
+	if (tag_v->id == REG_C_0) {
+		struct mlx5_priv *priv = dev->data->dev_private;
+		uint32_t msk_c0 = priv->sh->dv_regc0_mask;
+		uint32_t shl_c0 = rte_bsf32(msk_c0);
+
+		mask &= msk_c0;
+		mask <<= shl_c0;
+		value <<= shl_c0;
+	}
+	flow_dv_match_meta_reg(matcher, key, tag_v->id, value, mask);
 }
 
 /**
@@ -7280,7 +7311,7 @@ struct field_modify_info modify_tcp[] = {
 			last_item = MLX5_FLOW_ITEM_TAG;
 			break;
 		case MLX5_RTE_FLOW_ITEM_TYPE_TAG:
-			flow_dv_translate_mlx5_item_tag(match_mask,
+			flow_dv_translate_mlx5_item_tag(dev, match_mask,
 							match_value, items);
 			last_item = MLX5_FLOW_ITEM_TAG;
 			break;
-- 
1.8.3.1