kernel/inc/platform/interrupts.h

// This file is part of noxos and licensed under the MIT open source license

#ifndef NOX_INTERRUPTS_H
#define NOX_INTERRUPTS_H

#include "utils/stdtypes.h"

#define IDT_ENTRY_INTR_GATE  0b10001110
#define IDT_ENTRY_CALL_GATE  0b10001100
#define IDT_ENTRY_TRAP_GATE  0b10001111

#define PIC_MASTER_PORT      0x20
#define PIC_MASTER_COMMAND   0x20
#define PIC_MASTER_DATA      0x21
#define PIC_SLAVE_PORT       0xA0
#define PIC_SLAVE_COMMAND    0xA0
#define PIC_SLAVE_DATA       0xA1
#define PIC_END_OF_INTERRUPT 0x20

#define ICW1_ICW4            0x01
#define ICW1_INIT            0x10
#define ICW4_8086            0x01

#define IRQ_MASTER_OFFSET   0x20
#define IRQ_SLAVE_OFFSET    0x28

typedef enum {
    // Master PIC
    IRQ_PIT,
    IRQ_KEYBOARD,
    IRQ_CASCADE,
    IRQ_COM2,
    IRQ_COM1,
    IRQ_LPT2,
    IRQ_FLOPPY,
    IRQ_SPURIOUS,

    // Slave PIC
    IRQ_CMOS_RTC,
    IRQ_FREE_0,
    IRQ_FREE_1,
    IRQ_FREE_2,
    IRQ_PS2_MOUSE,
    IRQ_FPU,
    IRQ_ATA_PRIMARY,
    IRQ_ATA_SECONDARY
} pic_irq_E;

typedef struct {
    uint16_t  limit;
    uint64_t  offset;
} __attribute__((packed)) idt_register_T;

typedef struct {
    uint16_t  offset0;
    uint16_t  selector;
    uint8_t   ist;
    uint8_t   type_attribute;
    uint16_t  offset1;
    uint32_t  offset2;
    uint32_t  ignore;
} idt_descriptor_entry_T;

extern idt_register_T g_idt_register;
extern uint8_t        g_handling_interrupt;

void idt_init                   ();
void pic_init                   ();
void pic_remap                  ();
void pic_send_end_of_interrupt  (pic_irq_E irq);
void pic_mask_irq               (pic_irq_E irq);
void pic_unmask_irq             (pic_irq_E irq);

#endif //NOX_INTERRUPTS_H