9.2
9.3
9.4
10
Arbitration ......................................................................................................................................97
10.1
10.2
10.3
10.4
11
11.1
11.2
Interrupt Support...............................................................................................................101
11.3
Doorbell Interrupts ............................................................................................................103
11.4
Scratchpad Registers .......................................................................................................103
12
Error Handling .............................................................................................................................105
12.1
Error Signals .....................................................................................................................105
12.2
Parity Errors ......................................................................................................................107
12.3
13
JTAG Test Port............................................................................................................................111
13.1
JTAG Signals ....................................................................................................................111
13.2
13.2.1 Initialization ..........................................................................................................112
14
I2O Support .................................................................................................................................113
14.1
Inbound Message Passing ...............................................................................................113
14.2
Outbound Message Passing.............................................................................................115
14.3
Notes ................................................................................................................................116
15
VPD Support................................................................................................................................119
15.1
Reading VPD Information .................................................................................................119
15.2
Writing VPD Information ...................................................................................................120
16
List of Registers ...........................................................................................................................121
16.1
Register Summary ............................................................................................................121
16.2
Configuration Registers ....................................................................................................122
16.3
16.4
Address Decoding ............................................................................................................130
16.5
PCI Registers....................................................................................................................147
16.6
I2O Registers ....................................................................................................................165
21555 Non-Transparent PCI-to-PCI Bridge User Manual
Contents
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