Broadcom BCM1250 User Manual page 8

BCM1250/BCM1125/BCM1125H
Unaligned Buffer Descriptor format for Ethernet DMA ........................................................................154
DMA Coherence and Cache Options ......................................................................................................155
DMA Configurations .................................................................................................................................156
Ethernet and Serial DMA Engines...........................................................................................................157
Descriptor Count Watermarks .............................................................................................................157
Completion Interrupts ..........................................................................................................................158
Explicit Descriptor Interrupts................................................................................................................158
ASIC Mode Transfers ..........................................................................................................................159
Option and Flag Bits for Ethernet MACs ............................................................................................171
Control and Flag Bits for Synchronous Serial Interface.......................................................................174
Data Mover ................................................................................................................................................176
Data Mover Operation .........................................................................................................................176
CRC and Checksum Generators.........................................................................................................178
Checksum Generation..................................................................................................................178
CRC Generation...........................................................................................................................179
Computation Sizes and Bandwidth ..............................................................................................180
Examples......................................................................................................................................181
Data Mover Control Registers .............................................................................................................184
Data Mover Descriptors.......................................................................................................................187
Section 8: PCI Bus and HyperTransport Fabric ........................................................... 190
Introduction...............................................................................................................................................190
PCI and HyperTransport Address Range ...............................................................................................192
Memory Mapped Devices....................................................................................................................194
HyperTransport Expansion Space.......................................................................................................194
Configuration Space ............................................................................................................................194
PCI I/O Space......................................................................................................................................195
The SouthBridge, VGA and Subtractive Decode.................................................................................195
HyperTransport End Of Interrupt (EOI) Signaling Space ....................................................................198
Legacy Interrupt Acknowledge (IACK) Space .....................................................................................199
PCI Full Access Space ........................................................................................................................199
Special HyperTransport Space............................................................................................................199
HyperTransport Read Restrictions ......................................................................................................200
Endian Policies .........................................................................................................................................201
Little Endian System: No Swaps .........................................................................................................201
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B roa dcom Co rpo rat ion
User Manual
10/21/02
Document 1250_1125-UM100CB-R