4/29/2020
Godson 3A1000 Processor User Manual
74
111011 NPC
RdAddr
----
Read address extension
111111
-
Sync / Error
Will only forward
9.3 HyperTransport interrupt support
The HyperTransport controller provides 256 interrupt vectors, which can support Fix, Arbitor and other types of interrupts.
However, there is no support for hardware automatic EOI. For these two types of interrupts, the controller will automatically write after receiving
Into the interrupt register, and according to the interrupt mask register settings for the system interrupt controller interrupt notification. Concrete
For interrupt control, see the interrupt control register set in Section 5.
In addition, the controller specifically supports PIC interrupts to speed up this type of interrupt processing.
A typical PIC interrupt is completed by the following steps:
①
The PIC controller sends a PIC interrupt request to the system;
②
The system
Send the interrupt vector query to the PIC controller;
③
The PIC controller sends the interrupt vector number to the system;
④
The system clears the PIC controller
The corresponding interrupt on the controller. Only after the above four steps are completed, the PIC controller will issue the next interrupt to the system. for
79
Page 92
Godson 3A1000 Processor User Manual Part 1
Godson No.3 HyperTransport controller will automatically perform the first 3 steps and write the PIC interrupt vector to 256
Corresponding position in an interrupt vector. After the software system has processed the interrupt, it needs to perform step 4 processing, which is to
The PIC controller issues a clear interrupt. After that, the process of the next interrupt is started.
9.4 HyperTransport address window
9.4.1
HyperTransport space
In the Godson 3 processor, the default four HyperTransport address windows are as follows:
Table 9-4 Addresses of the default 4 HyperTransport address windows
Base address
End address
size
definition
0x0C00_0000_0000 0x0CFF_FFFF_FFFF
1 Tbytes
HT0_LO window
0x0D00_0000_0000 0x0DFF_FFFF_FFFF
1 Tbytes
HT0_HI window
0x0E00_0000_0000 0x0EFF_FFFF_FFFF
1 Tbytes
HT1_LO window
0x0F00_0000_0000
0x0FFF_FFFF_FFFF
1 Tbytes
HT1_HI window
By default (the system address window is not configured separately), the software
HyperTransport interface to access, in addition, the software can be configured through the address window on the crossbar
Set to access it with other address space (see section 2.5). Each HyperTransport interface has an internal 40-bit address space
The distribution of the specific address windows between is described in the following table.
The address window of HyperTransport interface protocol of Godson 3 processor is as follows:
Table 9-5 Address window distribution of HyperTransport interface of Loongson 3 processor
Base address
End address
size
definition
0x00_0000_0000
0xFC_FFFF_FFFF
1012 Gbytes
MEM space
0xFD_0000_0000
0xFD_F7FF_FFFF
3968 Mbytes
Keep
0xFD_F800_0000
0xFD_F8FF_FFFF
16 Mbytes
Interrupt
0xFD_F900_0000
0xFD_F90F_FFFF
1 Mbyte
PIC interrupt response
0xFD_F910_0000
0xFD_F91F_FFFF
1 Mbyte
system message
0xFD_F920_0000
0xFD_FAFF_FFFF
30 Mbytes
Keep
0xFD_FB00_0000
0xFD_FBFF_FFFF
16 Mbytes
HT controller configuration space
0xFD_FC00_0000
0xFD_FDFF_FFFF
32 Mbytes
I / O space
0xFD_FE00_0000
0xFD_FFFF_FFFF
32 Mbytes
HT bus configuration space