IB/mlx5: Advertise atomic capabilities in query device

In order to ensure IB spec atomic correctness in atomic operations, if
HW is configured to host endianness, advertise IB_ATOMIC_HCA.  if not,
advertise IB_ATOMIC_NONE.

Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

diff --git a/drivers/infiniband/hw/mlx5/main.c b/drivers/infiniband/hw/mlx5/main.c
index 8bee6fe732a124685bf0e74cd4808f83d6d6a202..03ce0f9fdd86cdbb5179535ec150918d4c7ac852 100644 (file)
--- a/drivers/infiniband/hw/mlx5/main.c
+++ b/drivers/infiniband/hw/mlx5/main.c
@@ -65,6 +65,10 @@ static char mlx5_version[] =
        DRIVER_NAME ": Mellanox Connect-IB Infiniband driver v"
        DRIVER_VERSION " (" DRIVER_RELDATE ")\n";
 
+enum {
+       MLX5_ATOMIC_SIZE_QP_8BYTES = 1 << 3,
+};
+
 static enum rdma_link_layer
 mlx5_port_type_cap_to_rdma_ll(int port_type_cap)
 {
@@ -296,6 +300,28 @@ static int mlx5_get_vport_access_method(struct ib_device *ibdev)
        return MLX5_VPORT_ACCESS_METHOD_HCA;
 }
 
+static void get_atomic_caps(struct mlx5_ib_dev *dev,
+                           struct ib_device_attr *props)
+{
+       u8 tmp;
+       u8 atomic_operations = MLX5_CAP_ATOMIC(dev->mdev, atomic_operations);
+       u8 atomic_size_qp = MLX5_CAP_ATOMIC(dev->mdev, atomic_size_qp);
+       u8 atomic_req_8B_endianness_mode =
+               MLX5_CAP_ATOMIC(dev->mdev, atomic_req_8B_endianess_mode);
+
+       /* Check if HW supports 8 bytes standard atomic operations and capable
+        * of host endianness respond
+        */
+       tmp = MLX5_ATOMIC_OPS_CMP_SWAP | MLX5_ATOMIC_OPS_FETCH_ADD;
+       if (((atomic_operations & tmp) == tmp) &&
+           (atomic_size_qp & MLX5_ATOMIC_SIZE_QP_8BYTES) &&
+           (atomic_req_8B_endianness_mode)) {
+               props->atomic_cap = IB_ATOMIC_HCA;
+       } else {
+               props->atomic_cap = IB_ATOMIC_NONE;
+       }
+}
+
 static int mlx5_query_system_image_guid(struct ib_device *ibdev,
                                        __be64 *sys_image_guid)
 {
@@ -496,7 +522,7 @@ static int mlx5_ib_query_device(struct ib_device *ibdev,
        props->max_res_rd_atom     = props->max_qp_rd_atom * props->max_qp;
        props->max_srq_sge         = max_rq_sg - 1;
        props->max_fast_reg_page_list_len = (unsigned int)-1;
-       props->atomic_cap          = IB_ATOMIC_NONE;
+       get_atomic_caps(dev, props);
        props->masked_atomic_cap   = IB_ATOMIC_NONE;
        props->max_mcast_grp       = 1 << MLX5_CAP_GEN(mdev, log_max_mcg);
        props->max_mcast_qp_attach = MLX5_CAP_GEN(mdev, max_qp_mcg);

diff --git a/include/linux/mlx5/driver.h b/include/linux/mlx5/driver.h
index 7b9c976b42d9067692201a068c4a7e7d5d49a143..53c57724c8dddce6c89853a721b5a7a5b0c6e730 100644 (file)
--- a/include/linux/mlx5/driver.h
+++ b/include/linux/mlx5/driver.h
@@ -115,6 +115,11 @@ enum {
        MLX5_REG_HOST_ENDIANNESS = 0x7004,
 };
 
+enum {
+       MLX5_ATOMIC_OPS_CMP_SWAP        = 1 << 0,
+       MLX5_ATOMIC_OPS_FETCH_ADD       = 1 << 1,
+};
+
 enum mlx5_page_fault_resume_flags {
        MLX5_PAGE_FAULT_RESUME_REQUESTOR = 1 << 0,
        MLX5_PAGE_FAULT_RESUME_WRITE     = 1 << 1,