APIC/IO-APIC Interrupt Controller
Advanced Programmable Interrupt Controller
Overview
APIC provides sophisticated interrupt handling compared to the legacy 8259 PIC. Modern systems use APIC for better interrupt distribution and MSI support.
APIC Components
Local APIC
- Per-CPU interrupt controller
- Receives interrupts from IO-APIC
- Handles CPU-local events
- Memory-mapped registers
IO-APIC
- Centralized interrupt controller
- Routes external interrupts
- Supports multiple CPUs
- Programmable routing
Key Takeaways
- ✓ Per-CPU local APIC
- ✓ Centralized IO-APIC
- ✓ Memory-mapped access
- ✓ Flexible interrupt routing
- ✓ MSI interrupt support