General Chipset Configuration
6.2
Interrupt Pin and Routing Configuration
Configuration of interrupts involves setting both the interrupt pin that a particular
device/function should be mapped to, as well as the routing of that pin to the
appropriate PIRQx signal that ultimately goes to either the PIC or APIC controller.
6.2.1
Interrupt Pin Configuration
The following registers tell each device which interrupt pin to report in the IPIN register
of their configuration space. Each register has one or more 4-bit field assigned to a
particular PCI function. This 4-bit field is defined as shown in Table 15.
Table 15.
Interrupt Pin Field Bit Decoding
Bits
Pin
0h
1h
No Interrupt
INTA#
2h
INTB#
3h
INTC#
4h
INTD#
5h – Fh
Reserved
Table 16.
Interrupt Pin Register Map
Address
Symbol
Register Name
Interface
LPC Interface
3100–3103h
3104–3107h
3108–310Bh
310C–310Fh
3110–3113h
3114–3117h
3118–311Ch
D31IP
D30IP
D29IP
D28IP
D27IP
D26IP
D02IP
Device 31 Interrupt Pin
Device 30 Interrupt Pin
Device 29 Interrupt Pin
Device 28 Interrupt Pin
Device 27 Interrupt Pin
Device 26 Interrupt Pin
Device 2 Interrupt Pin
SDIO/MMC (Ports 1-3)
USB Host (UHCI 1-3, EHCI)
PCI Express (Ports 1 and 2)
Intel HD Audio
USB Target
Intel GMA 500
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Datasheet