4/29/2020
Godson 3A1000 Processor User Manual
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Figure 9-4 Two-chip Loongson No. 3 16-bit interconnection structure
CPU0 HT0
HT
1
CPU1
HT0
16-bit HT bus
IO
16-bit HT bus
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Godson 3A1000 Processor User Manual Part 1
10 Low-speed IO controller configuration
Loongson No. 3 I / O controller includes PCI / PCI-X controller, LPC controller, UART controller, SPI controller,
GPIO and configuration registers. These I / O controllers share an AXI port, after the CPU's request is decoded by the address
Send to the appropriate device.
10.1 PCI / PCI-X controller
The PCI / PCI-X controller of Loongson 3 can be used as the main bridge to control the entire system, or it can be used as an ordinary
PCI / PCI-X devices work on the PCI / PCI-X bus. Its implementation conforms to PCI-X 1.0b and PCI 2.3 specifications. Dragon
The PCI / PCI-X controller of Core 3 also has a built-in PCI / PCI-X arbiter.
The configuration header of the PCI / PCI-X controller is located at 256 bytes starting at 0x1FE00000, as shown in Table 13-1.
Table 10-1 PCIX Controller Configuration Header
Byte 3
Byte 2
Byte 1
Byte 0
address
Device ID
Vendor ID
00
Status
Command
04
Class Code
Revision ID
08