Channel 0
Channel 1
Channel 2
Channel m
AINTC
FIQ
IRQ
ARM
Host Interrupt Mapping
of Channels
Peripheral A
Intr 0
Intr 1
Peripheral Z
Intr n
Intr (n–1)
n ≤ 100
m ≤ 31
Channel Mapping
of System Interrupts
Introduction
283
SPRUH82C – April 2013 – Revised September 2016
Copyright © 2013–2016, Texas Instruments Incorporated
ARM Interrupt Controller (AINTC)
11.1 Introduction
The ARM interrupt controller (AINTC) is an interface between interrupts coming from different parts of the
system (these are referred to as system interrupts in this document), and the ARM9 interrupt interface.
ARM9 supports two types of interrupts: FIQ and IRQ (these are referred to as host interrupts in this
document). The AINTC has the following features:
•
Supports up to 101 system interrupts.
•
Supports up to 32 interrupt channels.
•
Channels 0 and 1 are mapped (hard-wired) to the FIQ ARM interrupt and channels 2-31 are mapped to
IRQ ARM interrupt.
•
Each system interrupt can be enabled and disabled.
•
Each host interrupt can be enabled and disabled.
•
Hardware prioritization of interrupts.
•
Combining of interrupts from IPs to a single system interrupt.
•
Supports two active low debug interrupts.
See the ARM926EJ Technical Reference Manual for information about the ARM's FIQ and IRQ interrupts.
11.2 Interrupt Mapping
The AINTC supports up to 101 system interrupts from different peripherals to be mapped to 32 channels
inside the AINTC (see
). Interrupts from these 32 channels are further mapped to either an
ARM FIQ interrupt or an ARM IRQ interrupt.
•
Any of the 101 system interrupts can be mapped to any of the 32 channels.
•
Multiple interrupts can be mapped to a single channel.
•
An interrupt should not be mapped to more than one channel.
•
Interrupts from channels 0 and 1 are mapped to FIQ ARM interrupt on host side.
•
Interrupts from channels 2 to 31 are mapped to IRQ ARM interrupt on host side.
•
For I < k, interrupts on channel-I have higher priority than interrupts on channel-k.
•
For interrupts on same channel, priority is determined by the hardware interrupt number. The lower the
interrupt number, the higher the priority.
shows the system interrupt assignments for the AINTC.
Figure 11-1. AINTC Interrupt Mapping