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_platform.h>
  14
  15#include <asm/system.h>
  16#include <asm/mpic.h>
  17#include <asm/i8259.h>
  18
  19#ifdef CONFIG_PPC_I8259
  20static void mpc86xx_8259_cascade(unsigned int irq, struct irq_desc *desc)
  21{
  22        unsigned int cascade_irq = i8259_irq();
  23        if (cascade_irq != NO_IRQ)
  24                generic_handle_irq(cascade_irq);
  25        desc->chip->eoi(irq);
  26}
  27#endif  /* CONFIG_PPC_I8259 */
  28
  29void __init mpc86xx_init_irq(void)
  30{
  31        struct mpic *mpic;
  32        struct device_node *np;
  33        struct resource res;
  34#ifdef CONFIG_PPC_I8259
  35        struct device_node *cascade_node = NULL;
  36        int cascade_irq;
  37#endif
  38
  39        /* Determine PIC address. */
  40        np = of_find_node_by_type(NULL, "open-pic");
  41        if (np == NULL)
  42                return;
  43        of_address_to_resource(np, 0, &res);
  44
  45        mpic = mpic_alloc(np, res.start,
  46                        MPIC_PRIMARY | MPIC_WANTS_RESET |
  47                        MPIC_BIG_ENDIAN | MPIC_BROKEN_FRR_NIRQS |
  48                        MPIC_SINGLE_DEST_CPU,
  49                        0, 256, " MPIC     ");
  50        of_node_put(np);
  51        BUG_ON(mpic == NULL);
  52
  53        mpic_init(mpic);
  54
  55#ifdef CONFIG_PPC_I8259
  56        /* Initialize i8259 controller */
  57        for_each_node_by_type(np, "interrupt-controller")
  58                if (of_device_is_compatible(np, "chrp,iic")) {
  59                        cascade_node = np;
  60                        break;
  61                }
  62
  63        if (cascade_node == NULL) {
  64                printk(KERN_DEBUG "Could not find i8259 PIC\n");
  65                return;
  66        }
  67
  68        cascade_irq = irq_of_parse_and_map(cascade_node, 0);
  69        if (cascade_irq == NO_IRQ) {
  70                printk(KERN_ERR "Failed to map cascade interrupt\n");
  71                return;
  72        }
  73
  74        i8259_init(cascade_node, 0);
  75        of_node_put(cascade_node);
  76
  77        set_irq_chained_handler(cascade_irq, mpc86xx_8259_cascade);
  78#endif
  79}
  80