步骤：
- 设置IDT表 可以参考《Inter微处理器 第8版》p545
- 加载IDT表(只有开中断，它才开始作用)
设置IDT和ISR，idt.c的源代码如下所示
#include "io.h"
#include "video.h"
#include "kernel.h"
#include "asm.h"
#include "interrupt.h"
unsigned long long IDT[256] = {0};
struct DESCR{
unsigned short length;
unsigned long address;
}__attribute__((packed)) idt_descr = {256*8-1, (unsigned long )IDT};
static void isr_entry(int index, unsigned long long offset)
{
//中断门，《intel微处理器 第八版》p544
unsigned long long idt_entry = 0x00008e0000000000ULL | ((unsigned long long)CODE_SEL << 16);
idt_entry |= (offset << 32) & 0xffff000000000000ULL;
idt_entry |= (offset) & 0xffff;
IDT[index] = idt_entry;
}
void do_default_isr(unsigned long esp, unsigned long error_code)
{
kprint(0x14,"DEFAULT_ISR!!\n");
halt();
}
void idt_install(void)
{
unsigned int i = 0;
//先填充IDT表
for(i = 0; i < 256; i++)
{
isr_entry(i, (unsigned int )default_isr);
}
isr_entry(0, (unsigned int)divide_error);
isr_entry(1, (unsigned int)debug_exception);
isr_entry(2, (unsigned int)nmi);
isr_entry(3, (unsigned int)breakpoint);
isr_entry(4, (unsigned int)overflow);
isr_entry(5, (unsigned int)bound);
isr_entry(6, (unsigned int)invalid_opcode);
isr_entry(7, (unsigned int)coprocessor_not_available);
isr_entry(8, (unsigned int)double_fault);
isr_entry(9, (unsigned int)coprocessor_segment_overrun);
isr_entry(10, (unsigned int)invalid_tss);
isr_entry(11, (unsigned int)segment_not_present);
isr_entry(12, (unsigned int)stack_exception);
isr_entry(13, (unsigned int)protection_exception);
isr_entry(14, (unsigned int)page_fault);
isr_entry(15, (unsigned int)intel_reserved);
isr_entry(16, (unsigned int)coprecessor_error);
isr_entry(0x20, (unsigned int)timer); //IRQ0是时钟中断
//载入idt_descr
__asm__("lidt %0\n\t"::"m"(idt_descr));
}
void do_divide_error(unsigned long esp, unsigned long error_code)
{
kprint(0x14, "divide_error");
halt();
}
void do_debug_exception(unsigned long esp, unsigned long error_code)
{
kprint(0x14, "debug_exception");
halt();
}
void do_nmi(unsigned long esp, unsigned long error_code)
{
kprint(0x14, "nmi");
halt();
}
void do_breakpoint(unsigned long esp, unsigned long error_code)
{
kprint(0x14, "breakpoint");
halt();
}
void do_overflow(unsigned long esp, unsigned long error_code)
{
kprint(0x14, "overflow");
halt();
}
void do_bound(unsigned long esp, unsigned long error_code)
{
kprint(0x14, "bound");
halt();
}
void do_invalid_opcode(unsigned long esp, unsigned long error_code)
{
kprint(0x14, "invalid_opcode");
halt();
}
void do_coprocessor_not_available(unsigned long esp, unsigned long error_code)
{
kprint(0x14, "coprocessor_not_available");
halt();
}
void do_double_fault(unsigned long esp, unsigned long error_code)
{
kprint(0x14, "double_fault");
halt();
}
void do_coprocessor_segment_overrun(unsigned long esp, unsigned long error_code)
{
kprint(0x14, "coprocessor_segment_overrun");
halt();
}
void do_invalid_tss(unsigned long esp, unsigned long error_code)
{
kprint(0x14, "invalid_tss");
halt();
}
void do_segment_not_present(unsigned long esp, unsigned long error_code)
{
kprint(0x14, "segment_not_present");
halt();
}
void do_stack_exception(unsigned long esp, unsigned long error_code)
{
kprint(0x14, "stack_exception");
halt();
}
void do_protection_exception(unsigned long esp, unsigned long error_code)
{
kprint(0x14, "protection_exception");
halt();
}
void do_page_fault(unsigned long esp, unsigned long error_code)
{
kprint(0x14, "page_fault");
halt();
}
void do_intel_reserved(unsigned long esp, unsigned long error_code)
{
kprint(0x14, "intel_reserved");
halt();
}
void do_coprocessor_error(unsigned long esp, unsigned long error_code)
{
kprint(0x14, "coprocessor_error");
halt();
}
