toaruos/kernel/irq.S

.section .text
.align 4

.macro IRQ ident byte
    .global _irq\ident
    .type _irq\ident, @function
    _irq\ident:
        cli
        push $0x00
        push $\byte
        jmp irq_common
.endm

/* Interrupt Requests */
IRQ 0, 32
IRQ 1, 33
IRQ 2, 34
IRQ 3, 35
IRQ 4, 36
IRQ 5, 37
IRQ 6, 38
IRQ 7, 39
IRQ 8, 40
IRQ 9, 41
IRQ 10, 42
IRQ 11, 43
IRQ 12, 44
IRQ 13, 45
IRQ 14, 46
IRQ 15, 47

.extern irq_handler
.type irq_handler, @function

irq_common:
    /* Save all registers */
    pusha

    /* Save segment registers */
    push %ds
    push %es
    push %fs
    push %gs
    mov $0x10, %ax
    mov %ax, %ds
    mov %ax, %es
    mov %ax, %fs
    mov %ax, %gs
    cld

    /* Call interrupt handler */
    push %esp
    call irq_handler
    add $4, %esp

    /* Restore segment registers */
    pop %gs
    pop %fs
    pop %es
    pop %ds

    /* Restore all registers */
    popa
    /* Cleanup error code and IRQ # */
    add $8, %esp
    /* pop CS, EIP, EFLAGS, SS and ESP */
    iret