rapidio: add definitions of Component Tag fields
Add definition of the unique device identifier field in the component tag.
RIO_CTAG_UDEVID does not take all 32 bits of the component tag value to
allow future extensions to the component tag use.
Selected size of the RIO_CTAG_UDEVID field (17 bits) is sufficient to
accommodate maximum number of endpoints in large RIO network (16-bit id)
plus switches.
Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Thomas Moll <thomas.moll@sysgo.com>
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 9b55885..ff681eb 100644
--- a/include/linux/rio.h
+++ b/include/linux/rio.h
@@ -66,6 +66,16 @@
#define RIO_PW_MSG_SIZE 64
+/*
+ * A component tag value (stored in the component tag CSR) is used as device's
+ * unique identifier assigned during enumeration. Besides being used for
+ * identifying switches (which do not have device ID register), it also is used
+ * by error management notification and therefore has to be assigned
+ * to endpoints as well.
+ */
+#define RIO_CTAG_RESRVD 0xfffe0000 /* Reserved */
+#define RIO_CTAG_UDEVID 0x0001ffff /* Unique device identifier */
+
extern struct bus_type rio_bus_type;
extern struct device rio_bus;
extern struct list_head rio_devices; /* list of all devices */