2. RapidIO Ports > Packet Routing
CPS-1848 User Manual
30
June 2, 2014
Formal Status
This document is confidential and is subject to an NDA.
Integrated Device Technology
• RapidIO Specification (Rev. 2.1), Part 3: Common Transport Specification
• RapidIO Specification (Rev. 2.1), Part 6: LP-Serial Physical Layer Specification
• RapidIO Specification (Rev. 2.1), Part 7: System and Device Interoperability Specification
• RapidIO Specification (Rev. 2.1), Part 8: Error Management Extensions Specification
• RapidIO Specification (Rev. 2.1), Part 9: Flow Control Logic Layer Extensions Specification
• RapidIO Specification (Rev. 2.1), Part 11: Multicast Extensions Specification
• RapidIO Specification (Rev. 2.1), Annex I: Software/System Bring Up Specification
2.3
Packet Routing
The main function of each S-RIO port is to route received packets to the appropriate port(s) on the switch. Packet routing is
supported in a RapidIO standard method using routing tables and standard RapidIO registers for multicast functionality. Packet
routing is supplemented by implementation-specific registers for both the routing tables and for multicast. In addition, debug
features such as packet trace and filtering augment the normal packet routing.
The following sections describe routing table operation and programming, multicast operation and programming, and the
packet trace/filtering debug functionality.
2.3.1
Packet Routing Overview
Each S-RIO port provides a 256 entry Device Routing Table and a 256 entry Domain Routing Table. The scenario for the use
of the Domain and Device Routing Tables is a large system that has multiple chassis connected together, and multiple boards
in each chassis. The Domain Routing Table selects which chassis/board to route packets to, while the Device Routing Table
routes packets to a specific processing element on a board.
Figure 7: Routing Table Flowchart
8-bit destID?
Yes
destID[15:8]
matches
RIO_DOMAIN
Use Device Route
(Value 0xDD)
Yes
destID In
DOMAIN ROUTE
Use destID[15:8] to
Index Domain Routing
Table
DEVICE ROUTE
Use destID[7:0] to
Index Local Routing
Table
Drop Packet
(0xDF)
RTE_
DEFAULT_
PORT_
CSR
Multicast
Mask
(0x40-0x67)
Send Packet
to Port n
Multicast, 0xDF or Invalid
Port n
0xDE
Port n
Multicast
0xDF
0xDF or Invalid
0xDE
Po
rt n
No
No