rapidio: add handling of redundant routes

Detects RIO link to the already enumerated device and properly sets links
between device objects.  Changes to the enumeration/discovery logic:

1. Use Master Enable bit to signal end of the enumeration - agents may
   start their discovery process as soon as they see this bit set
   (Component Tag register was used before for this purpose).

2. Enumerator sets Component Tag (!= 0) immediately during device
   setup.  This allows to identify the device if the redundant route
   exists in a RIO system.

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Micha Nelissen <micha@neli.hopto.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/rio.h b/include/linux/rio.h
index 4fa5e3d..0bed941 100644
--- a/include/linux/rio.h
+++ b/include/linux/rio.h
@@ -177,6 +177,7 @@
  * @index: Port index, unique among all port interfaces of the same type
  * @sys_size: RapidIO common transport system size
  * @phy_type: RapidIO phy type
+ * @phys_efptr: RIO port extended features pointer
  * @name: Port name string
  * @priv: Master port private data
  */
@@ -198,6 +199,7 @@
 				 * 1 - Large size, 65536 devices.
 				 */
 	enum rio_phy_type phy_type;	/* RapidIO phy type */
+	u32 phys_efptr;
 	unsigned char name[40];
 	void *priv;		/* Master port private data */
 };