From: Guy Levi <guyle@mellanox.com>
Date: Thu, 15 Mar 2018 16:56:40 +0200
Subject: IB/mlx4: Add Scatter FCS support over WQ creation
Patch-mainline: v4.17-rc1
Git-commit: 6d06c9aa3816c26144f54d18c5b63ba9ff026fb9
References: bsc#1103988 FATE#326003

As a default, for Ethernet packets, the device scatters only the payload
of ingress packets. The scatter FCS feature lets the user to get the FCS
(Ethernet's frame check sequence) in the received WR's buffer as a 4
Bytes trailer following the packet's payload.

Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Guy Levi <guyle@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/infiniband/hw/mlx4/main.c    |   21 +++++++++++++--------
 drivers/infiniband/hw/mlx4/mlx4_ib.h |    1 +
 drivers/infiniband/hw/mlx4/qp.c      |   19 ++++++++++++++++++-
 3 files changed, 32 insertions(+), 9 deletions(-)

--- a/drivers/infiniband/hw/mlx4/main.c
+++ b/drivers/infiniband/hw/mlx4/main.c
@@ -559,14 +559,19 @@ static int mlx4_ib_query_device(struct i
 	props->timestamp_mask = 0xFFFFFFFFFFFFULL;
 	props->max_ah = INT_MAX;
 
-	if ((dev->dev->caps.flags2 & MLX4_DEV_CAP_FLAG2_RSS) &&
-	    (mlx4_ib_port_link_layer(ibdev, 1) == IB_LINK_LAYER_ETHERNET ||
-	     mlx4_ib_port_link_layer(ibdev, 2) == IB_LINK_LAYER_ETHERNET)) {
-		props->rss_caps.max_rwq_indirection_tables = props->max_qp;
-		props->rss_caps.max_rwq_indirection_table_size =
-			dev->dev->caps.max_rss_tbl_sz;
-		props->rss_caps.supported_qpts = 1 << IB_QPT_RAW_PACKET;
-		props->max_wq_type_rq = props->max_qp;
+	if (mlx4_ib_port_link_layer(ibdev, 1) == IB_LINK_LAYER_ETHERNET ||
+	    mlx4_ib_port_link_layer(ibdev, 2) == IB_LINK_LAYER_ETHERNET) {
+		if (dev->dev->caps.flags2 & MLX4_DEV_CAP_FLAG2_RSS) {
+			props->rss_caps.max_rwq_indirection_tables =
+				props->max_qp;
+			props->rss_caps.max_rwq_indirection_table_size =
+				dev->dev->caps.max_rss_tbl_sz;
+			props->rss_caps.supported_qpts = 1 << IB_QPT_RAW_PACKET;
+			props->max_wq_type_rq = props->max_qp;
+		}
+
+		if (dev->dev->caps.flags & MLX4_DEV_CAP_FLAG_FCS_KEEP)
+			props->raw_packet_caps |= IB_RAW_PACKET_CAP_SCATTER_FCS;
 	}
 
 	props->cq_caps.max_cq_moderation_count = MLX4_MAX_CQ_COUNT;
--- a/drivers/infiniband/hw/mlx4/mlx4_ib.h
+++ b/drivers/infiniband/hw/mlx4/mlx4_ib.h
@@ -189,6 +189,7 @@ enum mlx4_ib_qp_flags {
 	MLX4_IB_QP_LSO = IB_QP_CREATE_IPOIB_UD_LSO,
 	MLX4_IB_QP_BLOCK_MULTICAST_LOOPBACK = IB_QP_CREATE_BLOCK_MULTICAST_LOOPBACK,
 	MLX4_IB_QP_NETIF = IB_QP_CREATE_NETIF_QP,
+	MLX4_IB_QP_SCATTER_FCS = IB_QP_CREATE_SCATTER_FCS,
 
 	/* Mellanox specific flags start from IB_QP_CREATE_RESERVED_START */
 	MLX4_IB_ROCE_V2_GSI_QP = MLX4_IB_QP_CREATE_ROCE_V2_GSI,
--- a/drivers/infiniband/hw/mlx4/qp.c
+++ b/drivers/infiniband/hw/mlx4/qp.c
@@ -1096,6 +1096,17 @@ static int create_qp_common(struct mlx4_
 			qp->inl_recv_sz = ucmd.qp.inl_recv_sz;
 		}
 
+		if (init_attr->create_flags & IB_QP_CREATE_SCATTER_FCS) {
+			if (!(dev->dev->caps.flags &
+			      MLX4_DEV_CAP_FLAG_FCS_KEEP)) {
+				pr_debug("scatter FCS is unsupported\n");
+				err = -EOPNOTSUPP;
+				goto err;
+			}
+
+			qp->flags |= MLX4_IB_QP_SCATTER_FCS;
+		}
+
 		err = set_rq_size(dev, &init_attr->cap, !!pd->uobject,
 				  qp_has_rq(init_attr), qp, qp->inl_recv_sz);
 		if (err)
@@ -2234,6 +2245,9 @@ static int __mlx4_ib_modify_qp(void *src
 	if (qp->inl_recv_sz)
 		context->param3 |= cpu_to_be32(1 << 25);
 
+	if (qp->flags & MLX4_IB_QP_SCATTER_FCS)
+		context->param3 |= cpu_to_be32(1 << 29);
+
 	if (qp_type == IB_QPT_GSI || qp_type == IB_QPT_SMI)
 		context->mtu_msgmax = (IB_MTU_4096 << 5) | 11;
 	else if (qp_type == IB_QPT_RAW_PACKET)
@@ -4204,7 +4218,7 @@ struct ib_wq *mlx4_ib_create_wq(struct i
 		return ERR_PTR(-EOPNOTSUPP);
 	}
 
-	if (init_attr->create_flags) {
+	if (init_attr->create_flags & ~IB_WQ_FLAGS_SCATTER_FCS) {
 		pr_debug("unsupported create_flags %u\n",
 			 init_attr->create_flags);
 		return ERR_PTR(-EOPNOTSUPP);
@@ -4225,6 +4239,9 @@ struct ib_wq *mlx4_ib_create_wq(struct i
 	ib_qp_init_attr.recv_cq = init_attr->cq;
 	ib_qp_init_attr.send_cq = ib_qp_init_attr.recv_cq; /* Dummy CQ */
 
+	if (init_attr->create_flags & IB_WQ_FLAGS_SCATTER_FCS)
+		ib_qp_init_attr.create_flags |= IB_QP_CREATE_SCATTER_FCS;
+
 	err = create_qp_common(dev, pd, MLX4_IB_RWQ_SRC, &ib_qp_init_attr,
 			       udata, 0, &qp);
 	if (err) {