mlx4_core: Handle multi-physical function devices

MT26468 (PCI ID 0x6764) devices can expose multiple physical
functions.  The current driver only handles the primary physical
function.  For other functions, the QUERY_FW firmware command will
fail with the CMD_STAT_MULTI_FUNC_REQ error code.  Don't try to drive
such devices, but print a message saying the driver is skipping those
devices rather than just "QUERY_FW command failed."
Signed-off-by: Yevgeny Petrilin <yevgenyp@mellanox.co.il>

[ Rather than keeping unsupported devices bound to the driver, simply
  print a more informative error message and exit - Roland ]
Signed-off-by: Roland Dreier <rolandd@cisco.com>

drivers/net/mlx4/cmd.c

@@ -80,7 +80,9 @@ enum {
 	/* Bad management packet (silently discarded): */
 	CMD_STAT_BAD_PKT	= 0x30,
 	/* More outstanding CQEs in CQ than new CQ size: */
-	CMD_STAT_BAD_SIZE	= 0x40
+	CMD_STAT_BAD_SIZE	= 0x40,
+	/* Multi Function device support required: */
+	CMD_STAT_MULTI_FUNC_REQ	= 0x50,
 };
 
 enum {
@@ -128,6 +130,7 @@ static int mlx4_status_to_errno(u8 status)
 		[CMD_STAT_LAM_NOT_PRE]	  = -EAGAIN,
 		[CMD_STAT_BAD_PKT]	  = -EINVAL,
 		[CMD_STAT_BAD_SIZE]	  = -ENOMEM,
+		[CMD_STAT_MULTI_FUNC_REQ] = -EACCES,
 	};
 
 	if (status >= ARRAY_SIZE(trans_table) ||

drivers/net/mlx4/main.c

@@ -729,6 +729,9 @@ static int mlx4_init_hca(struct mlx4_dev *dev)
 
 	err = mlx4_QUERY_FW(dev);
 	if (err) {
+		if (err == -EACCES)
+			mlx4_info(dev, "non-primary physical function, skipping.\n");
+		else
 			mlx4_err(dev, "QUERY_FW command failed, aborting.\n");
 		return err;
 	}