mlx4_core: Disable SENSE_PORT for multifunction devices

In the current driver, the SENSE_PORT firmware command is issued as a
"wrapped" command, but the command handling code doesn't have a
wrapper, so it will never do anything other than log an error message.
The latest ConnectX-3 2.11.500 firmware reports the SENSE_PORT
capability even in multi-function (SR-IOV) mode, so the driver will
try to issue the command.

At least until the driver has a proper wrapper for SENSE_PORT, make
sure we disable the command for multi-function devices.

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

drivers/net/ethernet/mellanox/mlx4/main.c

@@ -300,6 +300,9 @@ static int mlx4_dev_cap(struct mlx4_dev *dev, struct mlx4_dev_cap *dev_cap)
 	/* Sense port always allowed on supported devices for ConnectX-1 and -2 */
 	if (mlx4_priv(dev)->pci_dev_data & MLX4_PCI_DEV_FORCE_SENSE_PORT)
 		dev->caps.flags |= MLX4_DEV_CAP_FLAG_SENSE_SUPPORT;
+	/* Don't do sense port on multifunction devices (for now at least) */
+	if (mlx4_is_mfunc(dev))
+		dev->caps.flags &= ~MLX4_DEV_CAP_FLAG_SENSE_SUPPORT;
 
 	dev->caps.log_num_macs  = log_num_mac;
 	dev->caps.log_num_vlans = MLX4_LOG_NUM_VLANS;