interrupt.c

/* SPDX-License-Identifier: MIT */

#include <x86.h>
#include <apic.h>
#include <platform.h>

#define NUM_ISR 256

/**
 * An interrupt service routine.
 */
typedef void (*isr_ptr_t)(void *arg);

/**
 * Represents a single entry in the interrupt handler table.
 */
typedef struct int_table_entry {
    isr_ptr_t callback;     /* Pointer to the ISR. */
    void     *arg;          /* Arguments to the ISR. */

    uint32_t allocated : 1; /* Whether or not this ISR was
                             * allocated.
                             */
    uint32_t edge      : 1; /* Edge(1)/Level(0) triggered. */
} int_table_entry_t;

/**
 * Interrupt handler table.
 */
static int_table_entry_t int_table[NUM_ISR];

void platform_init_interrupts(void)
{
}

void platform_int_handler(x86_interrupt_frame_t *frame)
{
    uint32_t           vector = frame->vector;
    int_table_entry_t *handler = &int_table[vector];

    /* edge triggered interrupt */
    if (handler->edge) {}

    /* invoke the registered callback */
    if (handler->callback) {
        handler->callback(handler->arg);
    }

    /* level triggered interrupt */
    if (!handler->edge) {}
}

void register_isr(uint32_t vector, isr_ptr_t callback, bool edge)
{
    int_table[vector].callback = callback;
    int_table[vector].allocated = true;
    int_table[vector].edge = edge;
}