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MOTOROLA
Contents
xv
CONTENTS
Paragraph
Number
Title
Page
Number
9.4.5.1.4
9.4.5.1.5
9.4.5.2
9.4.5.2.1
9.4.5.2.2
9.4.5.2.3
9.5
9.5.1
9.5.2
9.6
9.6.1
9.6.2
9.6.3
9.6.4
9.6.5
9.6.6
9.6.7
Attempted Accesses to ROM on the PCI BusHost Mode....................9-7
Attempted Accesses to ROM on the Memory Bus..................................9-8
Agent Mode Interactions..............................................................................9-8
Agent Mode DMA Transfers for PCI......................................................9-8
Attempted Accesses to Local ROM when ROM is on PCI.....................9-8
Attempted Access to ROM on the PCI BusAgent Mode.....................9-8
DMA Descriptors.................................................................................................9-8
Descriptors in Big-Endian Mode ...................................................................9-11
Descriptors in Little-Endian Mode.................................................................9-11
DMA Register Descriptions...............................................................................9-12
DMA Mode Registers (DMRs)......................................................................9-12
DMA Status Registers (DSRs).......................................................................9-14
Current Descriptor Address Registers (CDARs) ...........................................9-15
Source Address Registers (SARs)..................................................................9-16
Destination Address Registers (DARs)..........................................................9-17
Byte Count Registers (BCRs) ........................................................................9-18
Next Descriptor Address Registers (NDARs)................................................9-18
Chapter 10
Message Unit (with I
2
O)
10.1
10.2
10.2.1
10.2.2
10.2.3
10.3
10.3.1
10.3.2
10.3.3
10.3.3.1
10.3.3.1.1
10.3.3.1.2
10.3.3.2
10.3.3.2.1
10.3.3.2.2
10.3.4
10.3.4.1
10.3.4.1.1
10.3.4.1.2
10.3.4.1.3
10.3.4.1.4
Message Unit (MU) Overview...........................................................................10-1
Message and Doorbell Register Programming Model.......................................10-1
Message and Doorbell Register Summary.....................................................10-1
Message Register Descriptions......................................................................10-2
Doorbell Register Descriptions......................................................................10-3
I
2
O Interface.......................................................................................................10-4
PCI Configuration Identification....................................................................10-4
I
2
O Register Summary...................................................................................10-5
FIFO Descriptions..........................................................................................10-5
Inbound FIFOs...........................................................................................10-6
Inbound Free_List FIFO........................................................................10-7
Inbound Post_List FIFO ........................................................................10-7
Outbound FIFOs ........................................................................................10-7
Outbound Free_List FIFO......................................................................10-7
Outbound Post_List FIFO......................................................................10-8
I
2
O Register Descriptions..............................................................................10-8
PCI-Accessible I
2
O Registers....................................................................10-8
Outbound Message Interrupt Status Register (OMISR)........................10-8
Outbound Message Interrupt Mask Register (OMIMR)........................10-9
Inbound FIFO Queue Port Register (IFQPR)......................................10-10
Outbound FIFO Queue Port Register (OFQPR)..................................10-11