mlx4_en: Added self diagnostics test implementation

The selftest includes 5 features:
1. Interrupt test: Executing commands and receiving command completion
   on all our interrupt vectors.
2. Link test: Verifying we are connected to valid link partner.
3. Speed test: Check that we negotiated link speed correctly.
4. Registers test: Activate HW health check command.
5. Loopback test: Send a packet on loopback interface and catch it on RX side.

Signed-off-by: Yevgeny Petrilin <yevgenyp@mellanox.co.il>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/mlx4/fw.c b/drivers/net/mlx4/fw.c
index 04f42ae..a87bf3c 100644
--- a/drivers/net/mlx4/fw.c
+++ b/drivers/net/mlx4/fw.c
@@ -178,6 +178,7 @@
 #define QUERY_DEV_CAP_MAX_GID_OFFSET		0x3b
 #define QUERY_DEV_CAP_RATE_SUPPORT_OFFSET	0x3c
 #define QUERY_DEV_CAP_MAX_PKEY_OFFSET		0x3f
+#define QUERY_DEV_CAP_ETH_UC_LOOPBACK_OFFSET	0x43
 #define QUERY_DEV_CAP_FLAGS_OFFSET		0x44
 #define QUERY_DEV_CAP_RSVD_UAR_OFFSET		0x48
 #define QUERY_DEV_CAP_UAR_SZ_OFFSET		0x49
@@ -268,6 +269,8 @@
 	dev_cap->max_msg_sz = 1 << (field & 0x1f);
 	MLX4_GET(stat_rate, outbox, QUERY_DEV_CAP_RATE_SUPPORT_OFFSET);
 	dev_cap->stat_rate_support = stat_rate;
+	MLX4_GET(field, outbox, QUERY_DEV_CAP_ETH_UC_LOOPBACK_OFFSET);
+	dev_cap->loopback_support = field & 0x1;
 	MLX4_GET(dev_cap->flags, outbox, QUERY_DEV_CAP_FLAGS_OFFSET);
 	MLX4_GET(field, outbox, QUERY_DEV_CAP_RSVD_UAR_OFFSET);
 	dev_cap->reserved_uars = field >> 4;