IB/mlx4: Disable TSO for Connect-X rev. A0 HCAs

According to <http://marc.info/?t=138347640900004&r=1&w=2>, revision
A0 of Connect-X does not correctly assemble TSO packets.  Disable that
feature on that hardware revision.

Signed-off-by: Roland Dreier <roland@purestorage.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/drivers/infiniband/hw/mlx4/main.c b/drivers/infiniband/hw/mlx4/main.c
index e1e558a3d692..20f731f08c7e 100644
--- a/drivers/infiniband/hw/mlx4/main.c
+++ b/drivers/infiniband/hw/mlx4/main.c
@@ -59,6 +59,7 @@
 
 #define MLX4_IB_FLOW_MAX_PRIO 0xFFF
 #define MLX4_IB_FLOW_QPN_MASK 0xFFFFFF
+#define MLX4_IB_CARD_REV_A0   0xA0
 
 MODULE_AUTHOR("Roland Dreier");
 MODULE_DESCRIPTION("Mellanox ConnectX HCA InfiniBand driver");
@@ -158,7 +159,9 @@ static int mlx4_ib_query_device(struct ib_device *ibdev,
                 props->device_cap_flags |= IB_DEVICE_UD_AV_PORT_ENFORCE;
         if (dev->dev->caps.flags & MLX4_DEV_CAP_FLAG_IPOIB_CSUM)
                 props->device_cap_flags |= IB_DEVICE_UD_IP_CSUM;
-        if (dev->dev->caps.max_gso_sz && dev->dev->caps.flags & MLX4_DEV_CAP_FLAG_BLH)
+        if (dev->dev->caps.max_gso_sz &&
+            (dev->dev->rev_id != MLX4_IB_CARD_REV_A0) &&
+            (dev->dev->caps.flags & MLX4_DEV_CAP_FLAG_BLH))
                 props->device_cap_flags |= IB_DEVICE_UD_TSO;
         if (dev->dev->caps.bmme_flags & MLX4_BMME_FLAG_RESERVED_LKEY)
                 props->device_cap_flags |= IB_DEVICE_LOCAL_DMA_LKEY;