// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright 2008 Freescale Semiconductor, Inc.
 */

#include <linux/stddef.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/of.h>
#include <linux/of_irq.h>

#include <asm/mpic.h>
#include <asm/i8259.h>

#include "mpc86xx.h"

#ifdef CONFIG_PPC_I8259
static void mpc86xx_8259_cascade(struct irq_desc *desc)
{
        struct irq_chip *chip = irq_desc_get_chip(desc);
        unsigned int cascade_irq = i8259_irq();

        if (cascade_irq)
                generic_handle_irq(cascade_irq);

        chip->irq_eoi(&desc->irq_data);
}
#endif  /* CONFIG_PPC_I8259 */

void __init mpc86xx_init_irq(void)
{
#ifdef CONFIG_PPC_I8259
        struct device_node *np;
        struct device_node *cascade_node = NULL;
        int cascade_irq;
#endif

        struct mpic *mpic = mpic_alloc(NULL, 0, MPIC_BIG_ENDIAN |
                        MPIC_SINGLE_DEST_CPU,
                        0, 256, " MPIC     ");
        BUG_ON(mpic == NULL);

        mpic_init(mpic);

#ifdef CONFIG_PPC_I8259
        /* Initialize i8259 controller */
        for_each_node_by_type(np, "interrupt-controller")
                if (of_device_is_compatible(np, "chrp,iic")) {
                        cascade_node = np;
                        break;
                }

        if (cascade_node == NULL) {
                printk(KERN_DEBUG "Could not find i8259 PIC\n");
                return;
        }

        cascade_irq = irq_of_parse_and_map(cascade_node, 0);
        if (!cascade_irq) {
                printk(KERN_ERR "Failed to map cascade interrupt\n");
                return;
        }

        i8259_init(cascade_node, 0);
        of_node_put(cascade_node);

        irq_set_chained_handler(cascade_irq, mpc86xx_8259_cascade);
#endif
}