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>