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44409
Rev.
1.70
October 10
AMD SP5100 Databook
Functional Description
55
read/write. It supports up to two bus masters and 7 DMA channels. A bus master or DMA agent uses
LDRQ pin to assert bus master or DMA request. The host controller uses LFRAME# to indicate the start
or termination of a cycle. The following table shows a list of cycles supported by the host controller,
initiator, data flow direction, and their PCI counterparts.
Table 8-4: LPC Cycle List and Data Direction
Cycle
Size (bytes)
Initiator
Data Direction
PCI counterpart
Memory read
1
Host
P-2-Host
MemRead to LPC range
Memory write
1
Host
Host-2-P
MemWrit to LPC range
I/O read
1
Host
P-2-Host
IORead to LPC range
I/O write
1
Host
Host-2-P
IOWrit to LPC range
DMA read
1,2,4
Peripheral
Host-2-P
DMA Cntrl Setup; DMA data fetch
DMA write
1,2,4
Peripheral
P-2-Host
DMA Cntrl Setup; DMA data store
BM Memory
read
1,2,4
Peripheral
Host-2-P
DMA Cntrl Setup; DMA data fetch
BM Memory
write
1,2,4
Peripheral
P-2-Host
DMA Cntrl Setup; DMA data store
BM I/O read
1,2,4
Peripheral
Host-2-P
DMA Cntrl Setup; IO data fetch
BM I/O write
1,2,4
Peripheral
P-2-Host
DMA Cntrl Setup; IO data store
The host controller has a SERIRQ (Serial IRQ) pin, which is used by peripherals that require interrupt
support. All legacy interrupts are serialized on this pin, and then decoded by the host controller and sent
to the interrupt controller for processing. Please refer to the Serial IRQ Specification (Rev 5.4) for detailed
description on serial IRQ protocol.