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

   1/*
   2 * Copyright 2008 Freescale Semiconductor, Inc.
   3 *
   4 * This program is free software; you can redistribute  it and/or modify it
   5 * under  the terms of  the GNU General  Public License as published by the
   6 * Free Software Foundation;  either version 2 of the  License, or (at your
   7 * option) any later version.
   8 */
   9
  10#include <linux/stddef.h>
  11#include <linux/kernel.h>
  12#include <linux/interrupt.h>
  13#include <linux/of_irq.h>
  14#include <linux/of_platform.h>
  15
  16#include <asm/mpic.h>
  17#include <asm/i8259.h>
  18
  19#ifdef CONFIG_PPC_I8259
  20static void mpc86xx_8259_cascade(struct irq_desc *desc)
  21{
  22        struct irq_chip *chip = irq_desc_get_chip(desc);
  23        unsigned int cascade_irq = i8259_irq();
  24
  25        if (cascade_irq != NO_IRQ)
  26                generic_handle_irq(cascade_irq);
  27
  28        chip->irq_eoi(&desc->irq_data);
  29}
  30#endif  /* CONFIG_PPC_I8259 */
  31
  32void __init mpc86xx_init_irq(void)
  33{
  34#ifdef CONFIG_PPC_I8259
  35        struct device_node *np;
  36        struct device_node *cascade_node = NULL;
  37        int cascade_irq;
  38#endif
  39
  40        struct mpic *mpic = mpic_alloc(NULL, 0, MPIC_BIG_ENDIAN |
  41                        MPIC_SINGLE_DEST_CPU,
  42                        0, 256, " MPIC     ");
  43        BUG_ON(mpic == NULL);
  44
  45        mpic_init(mpic);
  46
  47#ifdef CONFIG_PPC_I8259
  48        /* Initialize i8259 controller */
  49        for_each_node_by_type(np, "interrupt-controller")
  50                if (of_device_is_compatible(np, "chrp,iic")) {
  51                        cascade_node = np;
  52                        break;
  53                }
  54
  55        if (cascade_node == NULL) {
  56                printk(KERN_DEBUG "Could not find i8259 PIC\n");
  57                return;
  58        }
  59
  60        cascade_irq = irq_of_parse_and_map(cascade_node, 0);
  61        if (cascade_irq == NO_IRQ) {
  62                printk(KERN_ERR "Failed to map cascade interrupt\n");
  63                return;
  64        }
  65
  66        i8259_init(cascade_node, 0);
  67        of_node_put(cascade_node);
  68
  69        irq_set_chained_handler(cascade_irq, mpc86xx_8259_cascade);
  70#endif
  71}
  72