LXR linux/arch/powerpc/platforms/86xx/pic.c

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Copyright 2008 Freescale Semiconductor, Inc.
   4 */
   5
   6#include <linux/stddef.h>
   7#include <linux/kernel.h>
   8#include <linux/interrupt.h>
   9#include <linux/of_irq.h>
  10#include <linux/of_platform.h>
  11
  12#include <asm/mpic.h>
  13#include <asm/i8259.h>
  14
  15#ifdef CONFIG_PPC_I8259
  16static void mpc86xx_8259_cascade(struct irq_desc *desc)
  17{
  18        struct irq_chip *chip = irq_desc_get_chip(desc);
  19        unsigned int cascade_irq = i8259_irq();
  20
  21        if (cascade_irq)
  22                generic_handle_irq(cascade_irq);
  23
  24        chip->irq_eoi(&desc->irq_data);
  25}
  26#endif  /* CONFIG_PPC_I8259 */
  27
  28void __init mpc86xx_init_irq(void)
  29{
  30#ifdef CONFIG_PPC_I8259
  31        struct device_node *np;
  32        struct device_node *cascade_node = NULL;
  33        int cascade_irq;
  34#endif
  35
  36        struct mpic *mpic = mpic_alloc(NULL, 0, MPIC_BIG_ENDIAN |
  37                        MPIC_SINGLE_DEST_CPU,
  38                        0, 256, " MPIC     ");
  39        BUG_ON(mpic == NULL);
  40
  41        mpic_init(mpic);
  42
  43#ifdef CONFIG_PPC_I8259
  44        /* Initialize i8259 controller */
  45        for_each_node_by_type(np, "interrupt-controller")
  46                if (of_device_is_compatible(np, "chrp,iic")) {
  47                        cascade_node = np;
  48                        break;
  49                }
  50
  51        if (cascade_node == NULL) {
  52                printk(KERN_DEBUG "Could not find i8259 PIC\n");
  53                return;
  54        }
  55
  56        cascade_irq = irq_of_parse_and_map(cascade_node, 0);
  57        if (!cascade_irq) {
  58                printk(KERN_ERR "Failed to map cascade interrupt\n");
  59                return;
  60        }
  61
  62        i8259_init(cascade_node, 0);
  63        of_node_put(cascade_node);
  64
  65        irq_set_chained_handler(cascade_irq, mpc86xx_8259_cascade);
  66#endif
  67}
  68