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Figure 11- 1 Configure read and write bus address generation
The PCI arbiter implements two-level round robin arbitration, bus docking, and isolation of damaged master devices. See its configuration and status
PXArb_Config and PXArb_Status registers. See Table 11-3 for the assignment of PCI bus request and response lines.
Table 11- 3 PCI / PCIX bus request and response line assignment
Request and answer line
description
0
Internal integrated PCI / PCIX controller
7: 1
External request 6 ~ 0
The rotation-based arbitration algorithm provides two levels, and the second level as a whole is scheduled as a member of the first level. When multiple
When the device applies for the bus at the same time, the first level device is rotated once, and the device with the highest priority in the second level can get the bus.
The arbiter is designed to be switched at any time as long as conditions permit. For some PCI devices that do not conform to the protocol,
Doing so may make it abnormal. Using mandatory priority allows these devices to occupy the bus through continuous requests.
Bus docking refers to whether or not to select one to give an enable signal when no device requests to use the bus. For already
As far as allowed devices are concerned, directly initiating bus operations can improve efficiency. The internal PCI arbiter provides two docking modes:
The last master device and the default master device. If you cannot dock in special occasions, you can set the arbiter to dock to
The default is No. 0 master device (internal controller), and the delay is 0.
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11.2 LPC controller
The LPC controller has the following characteristics:
●
Comply with LPC1.1 specification
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Support LPC access timeout counter