IB/mlx5: Introduce a new mini-CQE format

The new mini-CQE format includes the stride index, byte count and
packet checksum.
Stride index is needed for striding WQ feature.
This patch exposes this capability and enables its setting
via mlx5 UHW data as part of query device and cq creation.
Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Reviewed-by: Guy Levi <guyle@mellanox.com>
Signed-off-by: Yonatan Cohen <yonatanc@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/hw/mlx5/cq.c

@@ -742,6 +742,28 @@ static int alloc_cq_frag_buf(struct mlx5_ib_dev *dev,
 	return 0;
 }
 
+enum {
+	MLX5_CQE_RES_FORMAT_HASH = 0,
+	MLX5_CQE_RES_FORMAT_CSUM = 1,
+	MLX5_CQE_RES_FORMAT_CSUM_STRIDX = 3,
+};
+
+static int mini_cqe_res_format_to_hw(struct mlx5_ib_dev *dev, u8 format)
+{
+	switch (format) {
+	case MLX5_IB_CQE_RES_FORMAT_HASH:
+		return MLX5_CQE_RES_FORMAT_HASH;
+	case MLX5_IB_CQE_RES_FORMAT_CSUM:
+		return MLX5_CQE_RES_FORMAT_CSUM;
+	case MLX5_IB_CQE_RES_FORMAT_CSUM_STRIDX:
+		if (MLX5_CAP_GEN(dev->mdev, mini_cqe_resp_stride_index))
+			return MLX5_CQE_RES_FORMAT_CSUM_STRIDX;
+		return -EOPNOTSUPP;
+	default:
+		return -EINVAL;
+	}
+}
+
 static int create_cq_user(struct mlx5_ib_dev *dev, struct ib_udata *udata,
 			  struct ib_ucontext *context, struct mlx5_ib_cq *cq,
 			  int entries, u32 **cqb,
@@ -807,6 +829,8 @@ static int create_cq_user(struct mlx5_ib_dev *dev, struct ib_udata *udata,
 	*index = to_mucontext(context)->bfregi.sys_pages[0];
 
 	if (ucmd.cqe_comp_en == 1) {
+		int mini_cqe_format;
+
 		if (!((*cqe_size == 128 &&
 		       MLX5_CAP_GEN(dev->mdev, cqe_compression_128)) ||
 		      (*cqe_size == 64  &&
@@ -817,20 +841,18 @@ static int create_cq_user(struct mlx5_ib_dev *dev, struct ib_udata *udata,
 			goto err_cqb;
 		}
 
-		if (unlikely(!ucmd.cqe_comp_res_format ||
-			     !(ucmd.cqe_comp_res_format <
-			       MLX5_IB_CQE_RES_RESERVED) ||
-			     (ucmd.cqe_comp_res_format &
-			      (ucmd.cqe_comp_res_format - 1)))) {
-			err = -EOPNOTSUPP;
-			mlx5_ib_warn(dev, "CQE compression res format %d is not supported!\n",
+		mini_cqe_format =
+			mini_cqe_res_format_to_hw(dev,
 						  ucmd.cqe_comp_res_format);
+		if (mini_cqe_format < 0) {
+			err = mini_cqe_format;
+			mlx5_ib_dbg(dev, "CQE compression res format %d error: %d\n",
+				    ucmd.cqe_comp_res_format, err);
 			goto err_cqb;
 		}
 
 		MLX5_SET(cqc, cqc, cqe_comp_en, 1);
-		MLX5_SET(cqc, cqc, mini_cqe_res_format,
-			 ilog2(ucmd.cqe_comp_res_format));
+		MLX5_SET(cqc, cqc, mini_cqe_res_format, mini_cqe_format);
 	}
 
 	if (ucmd.flags & MLX5_IB_CREATE_CQ_FLAGS_CQE_128B_PAD) {

drivers/infiniband/hw/mlx5/main.c

@@ -993,6 +993,10 @@ static int mlx5_ib_query_device(struct ib_device *ibdev,
 			resp.cqe_comp_caps.supported_format =
 				MLX5_IB_CQE_RES_FORMAT_HASH |
 				MLX5_IB_CQE_RES_FORMAT_CSUM;
+
+			if (MLX5_CAP_GEN(dev->mdev, mini_cqe_resp_stride_index))
+				resp.cqe_comp_caps.supported_format |=
+					MLX5_IB_CQE_RES_FORMAT_CSUM_STRIDX;
 		}
 	}
 

include/uapi/rdma/mlx5-abi.h

@@ -163,7 +163,7 @@ struct mlx5_ib_rss_caps {
 enum mlx5_ib_cqe_comp_res_format {
 	MLX5_IB_CQE_RES_FORMAT_HASH	= 1 << 0,
 	MLX5_IB_CQE_RES_FORMAT_CSUM	= 1 << 1,
-	MLX5_IB_CQE_RES_RESERVED	= 1 << 2,
+	MLX5_IB_CQE_RES_FORMAT_CSUM_STRIDX = 1 << 2,
 };
 
 struct mlx5_ib_cqe_comp_caps {