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#include <stddef.h>
#include <stdint.h>
#include <stdbool.h>
#include <stdlib.h>
#include <arch.h>
#include <print.h>
#include <panic.h>
#include <arch/i686/pic.h>
#include <arch/i686/idt.h>
#include <time.h>
#include <drivers/ps2kb.h>
#include <drivers/ps2mouse.h>
#include <arch/i686/asm.h>
struct IdtEntry {
uint16_t isr_low;
uint16_t kernel_cs;
uint8_t _reserved;
uint8_t attributes;
uint16_t isr_high;
} __attribute__((packed));
struct Idtr {
uint16_t limit;
uint32_t base;
} __attribute__((packed));
enum IDTFlags {
IDT_FLAG_GATE_TASK = 0x5,
IDT_FLAG_GATE_16BIT_INT = 0x6,
IDT_FLAG_GATE_16BIT_TRAP = 0x7,
IDT_FLAG_GATE_32BIT_INT = 0xE,
IDT_FLAG_GATE_32BIT_TRAP = 0xF,
IDT_FLAG_RING0 = (0 << 5),
IDT_FLAG_RING1 = (1 << 5),
IDT_FLAG_RING2 = (2 << 5),
IDT_FLAG_RING3 = (3 << 5),
IDT_FLAG_PRESENT = 0x80,
};
static size_t timer = 0;
void idt_pic_eoi(uint8_t exception) {
pic_eoi(exception - PIC_REMAP_OFFSET);
}
void idt_pic_timer(void) {
timer += 1;
}
size_t get_systemtime(void) {
return timer;
}
void idt_pic_keyboard(void) {
ps2kb_recv();
}
void idt_pic_mouse(void) {
ps2mouse_recv();
}
void idt_exception_handler(uint8_t exception) {
char* msg;
switch(exception) {
case 0x00:
msg = "Division by zero";
break;
case 0x02:
msg = "NMI";
break;
case 0x04:
msg = "Overflow";
break;
case 0x06:
msg = "invalid opcode";
break;
case 0x08:
msg = "double fault";
break;
case 0x0A:
msg = "invalid task state segment";
break;
case 0x0C:
msg = "stack segment fault";
break;
case 0x0D:
msg = "general protection fault";
break;
case 0x0E:
msg = "page fault";
break;
default:
msg = "unknown exception";
break;
}
panic("E%u: %s", exception, msg);
}
__attribute__((aligned(0x10)))
static struct IdtEntry idt[256];
static struct Idtr idtr;
extern void* isr_stub_table[];
static void set_descriptor(uint8_t vector, void* isr, uint8_t flags) {
struct IdtEntry* entry = &idt[vector];
entry->isr_low = (size_t)isr & 0xffff;
entry->kernel_cs = 0x08;
entry->attributes = flags;
entry->isr_high = (size_t)isr >> 16;
entry->_reserved = 0;
}
void idt_init(void) {
idtr.base = (uintptr_t)&idt[0];
idtr.limit = (uint16_t)sizeof(struct IdtEntry) * IDT_SIZE - 1;
for(int i = 0; i < IDT_INTERRUPTS; i++) {
set_descriptor(i, isr_stub_table[i], 0x8e);
}
__asm__ volatile ("lidt %0" : : "m"(idtr));
}
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