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>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/rapidio/rio.h b/drivers/rapidio/rio.h
index d249a1205c7d..b1af414f15e6 100644
--- a/drivers/rapidio/rio.h
+++ b/drivers/rapidio/rio.h
@@ -38,6 +38,7 @@ extern int rio_std_route_get_entry(struct rio_mport *mport, u16 destid,
 extern int rio_std_route_clr_table(struct rio_mport *mport, u16 destid,
                                    u8 hopcount, u16 table);
 extern int rio_set_port_lockout(struct rio_dev *rdev, u32 pnum, int lock);
+extern struct rio_dev *rio_get_comptag(u32 comp_tag, struct rio_dev *from);
 
 /* Structures internal to the RIO core code */
 extern struct device_attribute rio_dev_attrs[];