vi Software Developer’s Manual
Contents
3.2.5 Receive Descriptor Write-Back .......................................................... 26
3.2.6 Receive Descriptor Queue Structure.................................................. 26
3.2.7 Receive Interrupts .............................................................................. 28
3.2.8 82544GC/EI Receive Interrupts ......................................................... 31
3.2.9 Receive Packet Checksum Offloading ............................................... 31
3.3 Packet Transmission ........................................................................................... 34
3.3.1 Transmit Data Storage ....................................................................... 35
3.3.2 Transmit Descriptors .......................................................................... 35
3.3.3 Legacy Transmit Descriptor Format ................................................... 36
3.3.4 Transmit Descriptor Special Field Format .......................................... 40
3.3.5 TCP/IP Context Transmit Descriptor Format...................................... 41
3.3.6 TCP/IP Context Descriptor Layout ..................................................... 42
3.3.7 TCP/IP Data Descriptor Format ......................................................... 46
3.4 Transmit Descriptor Ring Structure..................................................................... 51
3.4.1 Transmit Descriptor Fetching ............................................................. 53
3.4.2 Transmit Descriptor Write-back.......................................................... 53
3.4.3 Transmit Interrupts ............................................................................. 54
3.5 TCP Segmentation.............................................................................................. 55
3.5.1 Assumptions....................................................................................... 56
3.5.2 Transmission Process ........................................................................ 56
3.5.3 TCP Segmentation Performance ....................................................... 57
3.5.4 Packet Format .................................................................................... 57
3.5.5 TCP Segmentation Indication............................................................. 58
3.5.6 TCP Segmentation Use of Multiple Data Descriptors ........................ 59
3.5.7 IP and TCP/UDP Headers.................................................................. 60
3.5.8 Transmit Checksum Offloading with TCP Segmentation ................... 64
3.5.9 IP/TCP/UDP Header Updating ........................................................... 65
3.6 IP/TCP/UDP Transmit Checksum Offloading...................................................... 68
4 PCI Local Bus Interface......................................................................................... 71
4.1 PCI Configuration................................................................................................ 71
4.1.1 PCI-X Configuration Registers ........................................................... 79
4.1.2 Reserved and Undefined Addresses.................................................. 82
4.1.3 Message Signaled Interrupts.............................................................. 83
4.2 Commands.......................................................................................................... 85
4.3 PCI/PCI-X Command Usage............................................................................... 87
4.3.1 Memory Write Operations .................................................................. 87
4.3.2 Memory Read Operations .................................................................. 89
4.4 Cache Line Information ....................................................................................... 90
4.4.1 Target Transaction Termination ......................................................... 91
4.5 Interrupt Assignment (82547GI/EI Only) ............................................................. 91
4.6 LAN Disable ........................................................................................................ 91
4.7 CardBus Application (82541PI/GI/EI Only) ......................................................... 92
5 EEPROM Interface ................................................................................................... 93
5.1 General Overview ............................................................................................... 93
5.2 Component Identification Via Programming Interface......................................... 94
5.3 EEPROM Device and Interface........................................................................... 95
5.3.1 Software Access................................................................................. 96
5.4 Signature and CRC Fields .................................................................................. 96