arch/powerpc/platforms/512x/mpc5121_ads.c

   1 /*
   2  * Copyright (C) 2007 Freescale Semiconductor, Inc. All rights reserved.
   3  *
   4  * Author: John Rigby, <jrigby@freescale.com>, Thur Mar 29 2007
   5  *
   6  * Description:
   7  * MPC5121 ADS board setup
   8  *
   9  * This is free software; you can redistribute it and/or modify it
  10  * under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  */
  15
  16 #include <linux/kernel.h>
  17 #include <linux/io.h>
  18 #include <linux/irq.h>
  19 #include <linux/of_platform.h>
  20
  21 #include <asm/machdep.h>
  22 #include <asm/ipic.h>
  23 #include <asm/prom.h>
  24 #include <asm/time.h>
  25
  26 /**
  27  *      mpc512x_find_ips_freq - Find the IPS bus frequency for a device
  28  *      @node:  device node
  29  *
  30  *      Returns IPS bus frequency, or 0 if the bus frequency cannot be found.
  31  */
  32 unsigned long
  33 mpc512x_find_ips_freq(struct device_node *node)
  34 {
  35         struct device_node *np;
  36         const unsigned int *p_ips_freq = NULL;
  37
  38         of_node_get(node);
  39         while (node) {
  40                 p_ips_freq = of_get_property(node, "bus-frequency", NULL);
  41                 if (p_ips_freq)
  42                         break;
  43
  44                 np = of_get_parent(node);
  45                 of_node_put(node);
  46                 node = np;
  47         }
  48         if (node)
  49                 of_node_put(node);
  50
  51         return p_ips_freq ? *p_ips_freq : 0;
  52 }
  53 EXPORT_SYMBOL(mpc512x_find_ips_freq);
  54
  55 static struct of_device_id __initdata of_bus_ids[] = {
  56         { .name = "soc", },
  57         { .name = "localbus", },
  58         {},
  59 };
  60
  61 static void __init mpc5121_ads_declare_of_platform_devices(void)
  62 {
  63         /* Find every child of the SOC node and add it to of_platform */
  64         if (of_platform_bus_probe(NULL, of_bus_ids, NULL))
  65                 printk(KERN_ERR __FILE__ ": "
  66                         "Error while probing of_platform bus\n");
  67 }
  68
  69 static void __init mpc5121_ads_init_IRQ(void)
  70 {
  71         struct device_node *np;
  72
  73         np = of_find_compatible_node(NULL, NULL, "fsl,ipic");
  74         if (!np)
  75                 return;
  76
  77         ipic_init(np, 0);
  78         of_node_put(np);
  79
  80         /*
  81          * Initialize the default interrupt mapping priorities,
  82          * in case the boot rom changed something on us.
  83          */
  84         ipic_set_default_priority();
  85 }
  86
  87 /*
  88  * Called very early, MMU is off, device-tree isn't unflattened
  89  */
  90 static int __init mpc5121_ads_probe(void)
  91 {
  92         unsigned long root = of_get_flat_dt_root();
  93
  94         return of_flat_dt_is_compatible(root, "fsl,mpc5121ads");
  95 }
  96
  97 define_machine(mpc5121_ads) {
  98         .name                   = "MPC5121 ADS",
  99         .probe                  = mpc5121_ads_probe,
 100         .init                   = mpc5121_ads_declare_of_platform_devices,
 101         .init_IRQ               = mpc5121_ads_init_IRQ,
 102         .get_irq                = ipic_get_irq,
 103         .calibrate_decr         = generic_calibrate_decr,
 104 };