Intel IXP400 manual Document Number 252539, Revision

Intel® IXP400 Software

Access-Layer Components: Ethernet Access (IxEthAcc) API

Table 19. IX_OSAL_MBUF Header Definitions for the Ethernet Subsystem (Sheet 2 of 3)

			Queue
Field	Description
		Eth	Eth	Eth	Eth
		Rx			Tx
			Rx	Tx
		Free			Done
	New source address flag. A value of 0 indicates that a matching
	entry for the frame's source MAC address exists in the filtering		W(6)
ixp_ne_flags.new_src	database; a value of 1 indicates that no matching entry could be
	found. For NPE Ethernet firmware versions not supporting an NPE
	Learning/Filtering Tree, this field is always set to 0.
	Deferred filter flag. A value of 0 indicates a normal frame. A value of
	1 indicates that the NPE would normally have dropped the frame
	due to a filtering operation, but that the frame was preserved and
	presented to the Intel XScale core client because it contains a new
	source MAC address that must be learned. Furthermore, when this
	flag is set, the only IX_OSAL_MBUF fields that may be considered		W(6)
ixp_ne_flags.filter	to be valid are ixp_ne_next, ixp_ne_data, ixp_ne_dest_mac, and
	ixp_ne_src_mac. For NPE firmware versions that do not support
	source MAC address learning, this flag is always set to 0.
	NOTE: IxEthAcc will not forward these frames to the client
	application. After IxEthDB is notified of the new MAC
	address, the buffer will be replenished to the EthRxFree
	queue.
ixp_ne_flags.st_proto	Spanning tree protocol flag. A value of 0 indicates a normal frame;		W(6)	R
	a value of 1 indicates a spanning tree protocol BPDU.
	Link layer protocol indicator. This field reflects the state of a frame
	as it exits an NPE on the receive path (and is placed into an EthRx
ixp_ne_flags.link_prot	queue) or enters an NPE on the transmit path (from the EthTx		W(6)	R
	queue). It does not reflect the state of the frame when it is received
	or transmitted through an MII port. Its values are as listed in
	Table 22.
ixp_ne_flags.ip_prot	IP flag. A value of 0 indicates a non-IP payload; a value of 1		W(6)
	indicates an IP payload.
ixp_ne_flags.multicast	Multicast flag. A value of 0 indicates a non-multicast frame; a value		W(6)
	of 1 indicates a multicast frame.
ixp_ne_flags.broadcast	Broadcast flag. A value of 0 indicates a non-broadcast frame; a		W(6)
	value of 1 indicates a broadcast frame.
	Destination port override flag. A value of 0 indicates that the
	destination MAC address should be used by the NPE to determine
	the egress port for the frame; a value of 1 indicates that the value
ixp_ne_flags.port_over	of the ixp_ne_dest_port field should be used to determine the		W(5,6)	R(1)
	egress port. This flag is meaningful only for multiported NPEs, such
	as Ethernet NPE B on Intel® IXP46X product line processors.
	Single port NPEs, such as those on IXP42X product line
	processors, will ignore this flag.
	Transmit VLAN tagging override flag. A value 0 indicates that the
ixp_ne_flags.tag_over	default tagging behavior for the port/VID should be followed; a		W(5,6)	R
	value of 1 indicates that the default behavior should be overridden
	by the ixp_ne_flags.tag_mode flag.
	VLAN tag behavior flag (ignored if the value of
ixp_ne_flags.tag_mode	ixp_ne_flags.tag_over is 0). A value of 0 indicates that the output		W(5,6)	R(2)
	transmitted frame should be untagged; a value of 1 indicates that
	the output transmitted frame should be tagged.

April 2005	IXP400 Software Version 2.0	Programmer’s Guide
150	Document Number: 252539, Revision: 007