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IBM Dual Bridge and Memory Controller
dbamc01TOC.fm.01
July 13, 2000
Page iii
3.7.21 System I/O Register 0 (SIOR0) ..........................................................................................123
3.7.22 System I/O Register 1 (SIOR1) ..........................................................................................124
3.8 DMA Registers Space ..................................................................................................................125
3.8.1 DMA Global Control (GSCR) ................................................................................................125
3.8.2 DMA Global Status (GSSR) .................................................................................................126
3.8.3 DMA Transfer Control (XSCR) .............................................................................................127
3.8.4 DMA Transfer Status (XSSR) ...............................................................................................128
3.8.5 DMA Transfer PCI Address (XPAR) .....................................................................................130
3.8.6 DMA Transfer Write Back Address (XWAR) ........................................................................131
3.8.7 DMA Transfer Translated Address (XTAR) ..........................................................................132
3.9 System Standard Configuration Registers Space ....................................................................133
3.9.1 Device Characteristics Register (DCR) ................................................................................133
3.9.2 Device ID Register (DID) ......................................................................................................135
3.9.3 Base Address Register (BAR) ..............................................................................................136
3.9.4 Device Specific Configuration Space ...................................................................................137
3.9.5 PCI BAR Enable Register (PCIENB) ....................................................................................137
4. Addressing Model ....................................................................................................139
4.1 Address Maps ...............................................................................................................................139
4.2 CPU to PCI Addressing Model ....................................................................................................139
4.2.1 PREP and FPHB Modes ......................................................................................................139
4.2.2 Peripheral I/O Address Translation ......................................................................................141
4.3 PCI to System Memory ................................................................................................................142
4.3.1 PowerPC Reference Platform (PREP) Mode .......................................................................142
4.3.2 Flexible PCI Host Bridge (FPHB) Mode ...............................................................................145
4.4 60x Interface .................................................................................................................................145
4.4.1 Overview ...............................................................................................................................145
4.4.2 Endian Support .....................................................................................................................146
4.4.3 Processor Behavior in LE Mode ...........................................................................................146
4.4.4 Endian Behavior ...................................................................................................................146
4.5 60x Bus Arbiter Description ........................................................................................................149
4.5.1 Rotating Priority Resolution ..................................................................................................149
4.5.2 Address Bus Pipelining .........................................................................................................150
4.5.3 Arbiter Requirements ............................................................................................................150
4.5.4 Bus Enhancements ..............................................................................................................151
4.5.5 60x Bus Transfer Types and Sizes .......................................................................................152
4.6 Data Gathering .............................................................................................................................155
4.7 SYNC and EIEIO ...........................................................................................................................156
4.8 Address Retry (SYS_ARTRY) ......................................................................................................156
4.8.1 Precharging SYS_ARTRY and SYS_SHD ...........................................................................156
4.8.2 SYS_ARTRY Assertions ......................................................................................................156
4.8.3 Recommended SYS_ARTRY Procedure .............................................................................156
4.9 Locking Signal DLK .....................................................................................................................157
4.10 60x Bus Configuration ...............................................................................................................157
4.11 Error Handling for CPU-Initiated Transactions .......................................................................158
4.11.1 Checkstop Errors ................................................................................................................158
4.12 Memory Controller .....................................................................................................................162
4.12.1 Overview .............................................................................................................................162
4.12.2 Bank Definitions ..................................................................................................................163
4.12.3 SDRAM Banks ....................................................................................................................163