#include "types.h"

#include "kernel.h"

#include "interupt.h"

#include "interupt_entry.h"

#include "protected.h"

#include "task.h"

#include "lib.h"

#include "keyboard.h"

int_handler isr_tbl[ISR_NUM];

int k_reenter; /* detect reentering of interupt handler */

static void init_isr_tbl();

static void init_idt_entry(unsigned char vector, int_handler handler, \

unsigned char privilege);

extern void sys_call();

void init_idtr()

{

idtr.limit = IDT_SIZE*sizeof(struct idt_entry)-1;

idtr.base = (u32)idt;

load_idtr(idtr);

}

static void init_idt_entries()

{

/* error interupt */

init_idt_entry(0x00, divide_error, PRIVILEGE_KERN);

init_idt_entry(0x01, single_step_exception, PRIVILEGE_KERN);

init_idt_entry(0x02, nmi, PRIVILEGE_KERN);

init_idt_entry(0x03, breakpoint_exception, PRIVILEGE_USER);

init_idt_entry(0x04, overflow, PRIVILEGE_USER);

init_idt_entry(0x05, bounds_check, PRIVILEGE_KERN);

init_idt_entry(0x06, inval_opcode, PRIVILEGE_KERN);

init_idt_entry(0x07, copr_not_available, PRIVILEGE_KERN);

init_idt_entry(0x08, double_fault, PRIVILEGE_KERN);

init_idt_entry(0x09, copr_seg_overrun, PRIVILEGE_KERN);

init_idt_entry(0x0a, inval_tss, PRIVILEGE_KERN);

init_idt_entry(0x0b, segment_not_present, PRIVILEGE_KERN);

init_idt_entry(0x0c, stack_exception, PRIVILEGE_KERN);

init_idt_entry(0x0d, general_protection, PRIVILEGE_KERN);

init_idt_entry(0x0e, page_fault, PRIVILEGE_KERN);

init_idt_entry(0x10, copr_error, PRIVILEGE_KERN);

/* hardware interupt */

init_idt_entry(0x20, hwint00, PRIVILEGE_KERN);

init_idt_entry(0x21, hwint01, PRIVILEGE_KERN);

init_idt_entry(0x22, hwint02, PRIVILEGE_KERN);

init_idt_entry(0x23, hwint03, PRIVILEGE_KERN);

init_idt_entry(0x24, hwint04, PRIVILEGE_KERN);

init_idt_entry(0x25, hwint05, PRIVILEGE_KERN);

init_idt_entry(0x26, hwint06, PRIVILEGE_KERN);

init_idt_entry(0x27, hwint07, PRIVILEGE_KERN);

init_idt_entry(0x28, hwint08, PRIVILEGE_KERN);

init_idt_entry(0x29, hwint09, PRIVILEGE_KERN);

init_idt_entry(0x2a, hwint10, PRIVILEGE_KERN);

init_idt_entry(0x2b, hwint11, PRIVILEGE_KERN);

init_idt_entry(0x2c, hwint12, PRIVILEGE_KERN);

init_idt_entry(0x2d, hwint13, PRIVILEGE_KERN);

init_idt_entry(0x2e, hwint14, PRIVILEGE_KERN);

init_idt_entry(0x2f, hwint15, PRIVILEGE_KERN);

/* system call */

init_idt_entry(0x80, sys_call, PRIVILEGE_USER);

}

void setup_idt()

{

init_idt_entries();

init_isr_tbl();

}

void init_8259A()

{

out_byte(0x20, 0x11);

out_byte(0xa0, 0x11);

out_byte(0x21, 0x20);

out_byte(0xa1, 0x28);

out_byte(0x21, 0x4);

out_byte(0xa1, 0x2);

out_byte(0x21, 0x1);

out_byte(0xa1, 0x1);

out_byte(0x21, 0xfc);

out_byte(0xa1, 0xff);

}

void switch_ldt_in_gdt()

{

init_descriptor(&gdt[4], (u32)(ready_task->ldt), sizeof(struct descriptor) * LDT_SIZE - 1, DA_LDT);

}

void add_isr(int irq, int_handler handler)

{

isr_tbl[irq] = handler;

}

/* Below are real ISRs */

static void clock_routine(int irq)

{

ticks ++;

scheduler();

}

static void keyboard_routine(int irq)

{

u8 code;

code = in_byte(0x60);

if (keyboard_buf.count < KEYBOARD_BUF_LEN) {

*(keyboard_buf.head) = code;

keyboard_buf.head++;

if (keyboard_buf.head == keyboard_buf.buf + KEYBOARD_BUF_LEN)

keyboard_buf.head = keyboard_buf.buf;

keyboard_buf.count++;

}

}

static void default_routine(int irq)

{

}

void exception_handler(int vec_no, int err_code, int eip, int cs, int eflags)

{

int i;

char * err_msg[] = {"#DE Divide Error",

"#DB RESERVED",

"-- NMI Interrupt",

"#BP Breakpoint",

"#OF Overflow",

"#BR BOUND Range Exceeded",

"#UD Invalid Opcode (Undefined Opcode)",

"#NM Device Not Available (No Math Coprocessor)",

"#DF Double Fault",

" Coprocessor Segment Overrun (reserved)",

"#TS Invalid TSS",

"#NP Segment Not Present",

"#SS Stack Segment Fault",

"#GP General Protection",

"#PF Page Fault",

"-- (Intel reserved. Do not use.)",

"#MF x87 FPU Floating Point Error (Math Fault)",

"#AC Aligment Check",

"#MC Machine Check",

"#XF SIMD Floating Point Exception"

};

disp_pos = 0;

for (i=0; i<80*5; i++) {

disp_str(" ");

}

disp_pos = 0;

disp_str("Exception! --> ");

disp_str(err_msg[vec_no]);

disp_str("\n\n");

disp_str("EFLAGS:");

disp_int(eflags);

disp_str(" CS:");

disp_int(cs);

disp_str(" EIP:");

disp_int(eip);

if (err_code != 0xffffffff) {

disp_str(" Error code:");

disp_int(err_code);

}

}

static void init_isr_tbl()

{

int i;

for (i = 0; i < ISR_NUM; i++) {

isr_tbl[i] = default_routine;

}

add_isr(0, clock_routine);

add_isr(1, keyboard_routine);

}

/*

* init_idt_entry is used to initiate idt entries, using add_isr function

* to define specific Interupt Service Routine(ISR)

**/

static void init_idt_entry(unsigned char vector, int_handler handler, \

unsigned char privilege)

{

struct idt_entry *entry = &idt[vector];

u32 base = (u32)handler;

entry->offset_low = base & 0xffff;

entry->selector = 8; //TODO

entry->dcount = 0;

entry->attr = 0x8E | (privilege << 5);

entry->offset_high = (base >> 16) & 0xffff;

}