8.1
Introduction
8.2
Interrupt Mapping
SPRUFX7 – July 2008
Interrupt Controller
The device ARM Interrupt Controller (AINTC) has the following features:
•
Supports up to 64 interrupt channels (16 external channels)
•
Interrupt mask for each channel
•
Each interrupt channel is mappable to a Fast Interrupt Request (FIQ) or to an Interrupt Request (IRQ)
type of interrupt.
•
Hardware prioritization of simultaneous interrupts
•
Configurable interrupt priority (2 levels of FIQ and 6 levels of IRQ)
•
Configurable interrupt entry table (FIQ and IRQ priority table entry) to reduce interrupt processing time
The ARM core supports two interrupt types: FIQ and IRQ. See the ARM926EJ-S Technical Reference
Manual for detailed information about the ARM’s FIQ and IRQ interrupts. Each interrupt channel is
mappable to an FIQ or to an IRQ type of interrupt, and each channel can be enabled or disabled. The
INTC supports user-configurable interrupt-priority and interrupt entry addresses. Entry addresses minimize
the time spent jumping to interrupt service routines (ISRs). When an interrupt occurs, the corresponding
highest priority ISR’s address is stored in the INTC’s ENTRY register. The IRQ or FIQ interrupt routine can
read the ENTRY register and jump to the corresponding ISR directly. Thus, the ARM does not require a
software dispatcher to determine the asserted interrupt.
The AINTC takes up to 64 ARM device interrupts and maps them to either the IRQ or to the FIQ of the
ARM. Each interrupt is also assigned one of 8 priority levels (2 for FIQ, 6 for IRQ). For interrupts with the
same priority level, the priority is determined by the hardware interrupt number (the lowest number has the
highest priority).
shows the connection of device interrupts to the ARM.
Note:
The total number of interrupts in the device exceeds 64, which is the maximum value of the
AINTC module. Therefore, several interrupts are multiplexed and you must use the register
ARM_INTMUX in the system module to select the interrupt source for multiplexed interrupts.
Refer to the
for more information on the system module register ARM_INTMUX.
Table 8-1. AINTC Interrupt Connections
Interrupt
Acronym
Source
Interrupt
Acronym
Source
Number
Number
0
VPSSINT0
VPSS - INT0,
32
TINT0
Timer 0 - TINT12
Configurable via
VPSSBL register:
INTSEL
1
VPSSINT1
VPSS - INT1
33
TINT1
Timer 0 - TINT34
2
VPSSINT2
VPSS - INT2
34
TINT2
Timer 1 - TINT12
3
VPSSINT3
VPSS - INT3
35
TINT3
Timer 1 - TINT34
4
VPSSINT4
VPSS - INT4
36
PWMINT0
PWM0
88
Interrupt Controller
SPRUFX7 – July 2008