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#include "idt.h"
struct IDT_REGISTER IDTR={
8*IDT_MAX_ENTRY,
0x0 // IDT is located at physical address 0
};
// Interrupt functions (cf int.S)
extern u32
INT_DEFAULT,
INT_PAGE_FAULT,
INT_CLOCK,
INT_KEYPRESS,
INT_SYSCALL;
void idt_init(){
// Map entries, note that first 32 entries are used by the CPU
// and should be mapped to a function (INT_DEFAULT here)
for(int i=0;i<IDT_MAX_ENTRY;i++){
idt_write_entry((IDT_ENTRY){0x08,(u32)&INT_DEFAULT,IDT_INT_GATE|IDT_P},i);
if(i==14)
idt_write_entry((IDT_ENTRY){0x08,(u32)&INT_PAGE_FAULT,IDT_INT_GATE|IDT_P},i);
if(i==32)
idt_write_entry((IDT_ENTRY){0x08,(u32)&INT_CLOCK,IDT_INT_GATE|IDT_P},i);
if(i==33)
idt_write_entry((IDT_ENTRY){0x08,(u32)&INT_KEYPRESS,IDT_INT_GATE|IDT_P},i);
if(i==48)
idt_write_entry((IDT_ENTRY){0x08,(u32)&INT_SYSCALL,IDT_INT_GATE|IDT_P|IDT_PRVL_3},i);
}
// Load IDT
asm("lidtl (IDTR)");
}
void idt_write_entry(IDT_ENTRY entry, int id){
int descriptor[2];
descriptor[0]=entry.offset & 0xFFFF | entry.segment << 16;
descriptor[1]=entry.type & 0xFFFF | entry.offset & 0xFFFF0000;
memcpy((void*)descriptor, (void *)(IDTR.base+(id*8)),8);
}
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