62 lines
1.5 KiB
C
62 lines
1.5 KiB
C
#ifndef IDT_H
|
|
#define IDT_H
|
|
|
|
#include <stdint.h>
|
|
#include "gdt.h"
|
|
#include "isr.h"
|
|
|
|
#define IDT_NB_ENTRIES 34
|
|
#define IDT_SIZE (IDT_NB_ENTRIES * sizeof(struct idt_entry))
|
|
|
|
#define INTEL_DEFINED 21
|
|
#define INTEL_UNUSED 31
|
|
|
|
#define INTERRUPT_TYPE 0x6
|
|
#define TRAP_TYPE 0x7
|
|
|
|
struct idt_entry
|
|
{
|
|
uint16_t offset_1 : 16; // 16 lsb of isr address
|
|
struct segment_selector selector;
|
|
|
|
uint8_t zero_1 : 8; // unused, set to 0
|
|
uint8_t type : 3; // gate type
|
|
uint8_t size : 1; // 0 => 16-bits 1 => 32-bits
|
|
uint8_t zero_2 : 1; // set to 0 for interrupt and trap gates
|
|
uint8_t desc_priv : 2; // descriptor privilege
|
|
uint8_t present : 1; // always 1
|
|
|
|
uint16_t offset_2 : 16; // 16 msb of isr address
|
|
} __attribute__ ((packed));
|
|
|
|
struct idt
|
|
{
|
|
struct idt_entry entries[IDT_NB_ENTRIES];
|
|
};
|
|
|
|
struct idt_r
|
|
{
|
|
uint16_t limit; // total size of the IDT - 1 in bytes
|
|
uint32_t addr; // base address of the IDT
|
|
} __attribute__ ((packed));
|
|
|
|
// This struct is used to get int_code and err_code pushed to the stack
|
|
// by the isr.
|
|
struct int_args
|
|
{
|
|
uint32_t int_code;
|
|
uint32_t err_code;
|
|
} __attribute__ ((packed));
|
|
|
|
// This struct is used to know how to fill the idt entries
|
|
struct idt_entry_info
|
|
{
|
|
void (*isr)(void); // function pointer on interrupt service routine (isr)
|
|
uint32_t type; // gate type
|
|
};
|
|
|
|
void init_idt(void);
|
|
void handle_interrupt(struct int_args *args);
|
|
|
|
#endif /* !IDT_H */
|