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#include <kernel/io/io.h>
#include <kernel/interrupts/interrupts.h>
extern void irq0();
extern void irq1();
extern void irq2();
extern void irq3();
extern void irq4();
extern void irq5();
extern void irq6();
extern void irq7();
extern void irq8();
extern void irq9();
extern void irq10();
extern void irq11();
extern void irq12();
extern void irq13();
extern void irq14();
extern void irq15();
// Array to handle custom IRQ handlers
void *irq_routines[16] = {
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0
};
// Install custom IRQ handler
void irq_install_handler(int irq, void (*handler)(struct regs *r)) {
irq_routines[irq] = handler;
}
// Removes the custom IRQ handler
void irq_uninstall_handler(int irq) {
irq_routines[irq] = 0;
}
int irq_is_installed(int irq) {
return irq_routines[irq] != 0;
}
// Remap IRQs for protected mode compatibility via the PIC
void irq_remap(void) {
send_b(0x20, 0x11);
send_b(0xA0, 0x11);
send_b(0x21, 0x20);
send_b(0xA1, 0x28);
send_b(0x21, 0x04);
send_b(0xA1, 0x02);
send_b(0x21, 0x01);
send_b(0xA1, 0x01);
send_b(0x21, 0x0);
send_b(0xA1, 0x0);
}
// Map ISRs to the correct entries in the IDT
void irq_install() {
irq_remap();
idt_set_gate(32, (unsigned) irq0, 0x08, 0x8E);
idt_set_gate(33, (unsigned) irq1, 0x08, 0x8E);
idt_set_gate(34, (unsigned) irq2, 0x08, 0x8E);
idt_set_gate(35, (unsigned) irq3, 0x08, 0x8E);
idt_set_gate(36, (unsigned) irq4, 0x08, 0x8E);
idt_set_gate(37, (unsigned) irq5, 0x08, 0x8E);
idt_set_gate(38, (unsigned) irq6, 0x08, 0x8E);
idt_set_gate(39, (unsigned) irq7, 0x08, 0x8E);
idt_set_gate(40, (unsigned) irq8, 0x08, 0x8E);
idt_set_gate(41, (unsigned) irq9, 0x08, 0x8E);
idt_set_gate(42, (unsigned) irq10, 0x08, 0x8E);
idt_set_gate(43, (unsigned) irq11, 0x08, 0x8E);
idt_set_gate(44, (unsigned) irq12, 0x08, 0x8E);
idt_set_gate(45, (unsigned) irq13, 0x08, 0x8E);
idt_set_gate(46, (unsigned) irq14, 0x08, 0x8E);
idt_set_gate(47, (unsigned) irq15, 0x08, 0x8E);
}
// Handle IRQ ISRs
void irq_handler(struct regs *r) {
void (*handler)(struct regs *r);
// Execute custom handler if exists
handler = irq_routines[r->int_no - 32];
if (handler) {
handler(r);
}
// Send end of interrupt to second (slave) IRQ controller
if (r->int_no >= 40) {
send_b(0xA0, 0x20);
}
// Send end of interrupt to master interrupt controller
send_b(0x20, 0x20);
}
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