Pci Target Interface Supported Commands - Intel IXP45X Developer's Manual

FIFOs. The Target Interface FIFOs are 8 words deep. The PCI-target interface — in
conjunction with the target interface FIFOs — will use the South AHB Master interface
of the PCI Controller to provide read and write access to AHB agents, PCI Controller
Configuration and status registers. The PCI Controller PCI Configuration Registers are
accessed through configuration cycles. Target transactions will be accessed directly
from the PCI-Target Interface.
Table 189
processors are used as a target of a PCI transaction. The PCI Target interface does not
support the following features:
• Lock cycles
• VGA palette snoop
• Dual address cycles
• Cache-line wrap mode addressing (Disconnected after first data phase of
transaction)
• Type 1 Configuration space
Table 189.

PCI Target Interface Supported Commands

PCI Command/Byte
Enables
When the IXP45X/IXP46X network processors want to use an external PCI device as
the target of a PCI transfer, the PCI Controller Initiator interface will be used to
generate the appropriate PCI bus cycles and forward the information to the PCI bus.
There are three ways in which PCI bus cycles may be initiated:
— The DMA channels generate PCI Memory cycles. Refer to
on page 536
— AHB masters generate PCI Memory cycles using memory-mapped direct access
on the AHB bus. Refer to
I/O Base Address Register, and PCI Memory Base Address Register" on
page 507
® ®
Intel IXP45X and Intel IXP46X Product Line of Network Processors
Develepor's Manual
498
®
Intel IXP45X and Intel
lists the supported command types, when the IXP45X/IXP46X network
0x0 Interrupt Acknowledge
0x1 Special Cycle
0x2 I/O Read
0x3 I/O Write
0x4 (Reserved)
0x5 (Reserved)
0x6 Memory Read
0x7 Memory Write
0x8 (Reserved)
0x9 (Reserved)
0xA Configuration Read
0xB Configuration Write
0xC Memory Read Multiple
0xD Dual Address Cycle
0xE Memory Read Line
0xF Memory Write and Invalidate
for additional details.
for additional details.
®
IXP46X Product Line of Network Processors—PCI Controller
Command Type
"Example: AHB Memory Base Address Register, AHB
Support
Not Supported
Not Supported
Supported
Supported
Supported
Supported
Supported
Supported
Converted To Memory Read
Not Supported
Converted To Memory Read
Converted To Memory Write
"PCI Controller DMA"
August 2006
Order Number: 306262-004US