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/* This file contains routines for initializing the 8259 interrupt controller:
* put_irq_handler: register an interrupt handler
* rm_irq_handler: deregister an interrupt handler
* intr_handle: handle a hardware interrupt
* intr_init: initialize the interrupt controller(s)
*/
#include "kernel/kernel.h"
#include "arch_proto.h"
#include "hw_intr.h"
#include <machine/cpu.h>
#define ICW1_AT 0x11 /* edge triggered, cascade, need ICW4 */
#define ICW1_PC 0x13 /* edge triggered, no cascade, need ICW4 */
#define ICW1_PS 0x19 /* level triggered, cascade, need ICW4 */
#define ICW4_AT_SLAVE 0x01 /* not SFNM, not buffered, normal EOI, 8086 */
#define ICW4_AT_MASTER 0x05 /* not SFNM, not buffered, normal EOI, 8086 */
#define ICW4_PC_SLAVE 0x09 /* not SFNM, buffered, normal EOI, 8086 */
#define ICW4_PC_MASTER 0x0D /* not SFNM, buffered, normal EOI, 8086 */
#define ICW4_AT_AEOI_SLAVE 0x03 /* not SFNM, not buffered, auto EOI, 8086 */
#define ICW4_AT_AEOI_MASTER 0x07 /* not SFNM, not buffered, auto EOI, 8086 */
#define ICW4_PC_AEOI_SLAVE 0x0B /* not SFNM, buffered, auto EOI, 8086 */
#define ICW4_PC_AEOI_MASTER 0x0F /* not SFNM, buffered, auto EOI, 8086 */
/*===========================================================================*
* intr_init *
*===========================================================================*/
int intr_init(const int auto_eoi)
{
/* Initialize the 8259s, finishing with all interrupts disabled. */
outb( INT_CTL, ICW1_AT);
outb( INT_CTLMASK, IRQ0_VECTOR);
/* ICW2 for master */
outb( INT_CTLMASK, (1 << CASCADE_IRQ));
/* ICW3 tells slaves */
if (auto_eoi)
outb( INT_CTLMASK, ICW4_AT_AEOI_MASTER);
else
outb( INT_CTLMASK, ICW4_AT_MASTER);
outb( INT_CTLMASK, ~(1 << CASCADE_IRQ)); /* IRQ 0-7 mask */
outb( INT2_CTL, ICW1_AT);
outb( INT2_CTLMASK, IRQ8_VECTOR);
/* ICW2 for slave */
outb( INT2_CTLMASK, CASCADE_IRQ); /* ICW3 is slave nr */
if (auto_eoi)
outb( INT2_CTLMASK, ICW4_AT_AEOI_SLAVE);
else
outb( INT2_CTLMASK, ICW4_AT_SLAVE);
outb( INT2_CTLMASK, ~0); /* IRQ 8-15 mask */
return OK;
}
void irq_8259_unmask(const int irq)
{
const unsigned ctl_mask = irq < 8 ? INT_CTLMASK : INT2_CTLMASK;
outb(ctl_mask, inb(ctl_mask) & ~(1 << (irq & 0x7)));
}
void irq_8259_mask(const int irq)
{
const unsigned ctl_mask = irq < 8 ? INT_CTLMASK : INT2_CTLMASK;
outb(ctl_mask, inb(ctl_mask) | (1 << (irq & 0x7)));
}
/* Disable 8259 - write 0xFF in OCW1 master and slave. */
void i8259_disable(void)
{
outb(INT2_CTLMASK, 0xFF);
outb(INT_CTLMASK, 0xFF);
inb(INT_CTLMASK);
}
void irq_8259_eoi(int irq)
{
if (irq < 8)
eoi_8259_master();
else
eoi_8259_slave();
}
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