Intel® IXP400 Software
Access-Layer Components: Ethernet Access (IxEthAcc) API
April 2005 IXP400 Software Version 2.0 Programmer’s Guide
136 Document Number: 252539, Revision: 007There are two scheduling disciplines selectable via the IxEthAccTxSchedulerDiscipline (). The frame submit behavior will be different for each case. Available scheduling disciplines are No Priority and Priority.Figure 50. Ethernet Transmit Frame Data Buffer Flow
TxEnet0
TxEnet1
TxEnetDone
Codelet or client applic ation
IxEthAcc
IxQMgr
1. Initialization s, Po rt
Enables, Callback
Registration...
2. Frame Submit (Port 0)
Frame Submit (Port 1)
Frame Submit (Port 2)
4. Load Tx Queues when
low threshold reached
6. ixp_buf moved to TxDone
queue
7. Demux free buffer to
port specific callbac k
8. TxDoneCallback (Por t 0)
TxDoneCallback (Port 1)
TxDoneCallback (Port 2)
3a. Route Tx buffers to
8 priority queues
B2364-04
FIFO_PRIORITY
3b.Load Tx
Queues
directly
FIFO_NO_PRIORITY
5. Move to NPE queue,
then physical transmission
NPE C
Sw queu e for
deferred submission
NPE B
TxEnet2
NPE A