arch/mips/kernel/prom.c

   1 /*
   2  * MIPS support for CONFIG_OF device tree support
   3  *
   4  * Copyright (C) 2010 Cisco Systems Inc. <dediao@cisco.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10
  11 #include <linux/init.h>
  12 #include <linux/module.h>
  13 #include <linux/errno.h>
  14 #include <linux/types.h>
  15 #include <linux/bootmem.h>
  16 #include <linux/initrd.h>
  17 #include <linux/debugfs.h>
  18 #include <linux/of.h>
  19 #include <linux/of_fdt.h>
  20 #include <linux/of_irq.h>
  21 #include <linux/of_platform.h>
  22
  23 #include <asm/page.h>
  24 #include <asm/prom.h>
  25
  26 int __init early_init_dt_scan_memory_arch(unsigned long node,
  27                                           const char *uname, int depth,
  28                                           void *data)
  29 {
  30         return early_init_dt_scan_memory(node, uname, depth, data);
  31 }
  32
  33 void __init early_init_dt_add_memory_arch(u64 base, u64 size)
  34 {
  35         return add_memory_region(base, size, BOOT_MEM_RAM);
  36 }
  37
  38 int __init reserve_mem_mach(unsigned long addr, unsigned long size)
  39 {
  40         return reserve_bootmem(addr, size, BOOTMEM_DEFAULT);
  41 }
  42
  43 void __init free_mem_mach(unsigned long addr, unsigned long size)
  44 {
  45         return free_bootmem(addr, size);
  46 }
  47
  48 void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
  49 {
  50         return __alloc_bootmem(size, align, __pa(MAX_DMA_ADDRESS));
  51 }
  52
  53 #ifdef CONFIG_BLK_DEV_INITRD
  54 void __init early_init_dt_setup_initrd_arch(unsigned long start,
  55                                             unsigned long end)
  56 {
  57         initrd_start = (unsigned long)__va(start);
  58         initrd_end = (unsigned long)__va(end);
  59         initrd_below_start_ok = 1;
  60 }
  61 #endif
  62
  63 /*
  64  * irq_create_of_mapping - Hook to resolve OF irq specifier into a Linux irq#
  65  *
  66  * Currently the mapping mechanism is trivial; simple flat hwirq numbers are
  67  * mapped 1:1 onto Linux irq numbers.  Cascaded irq controllers are not
  68  * supported.
  69  */
  70 unsigned int irq_create_of_mapping(struct device_node *controller,
  71                                    const u32 *intspec, unsigned int intsize)
  72 {
  73         return intspec[0];
  74 }
  75 EXPORT_SYMBOL_GPL(irq_create_of_mapping);
  76
  77 void __init early_init_devtree(void *params)
  78 {
  79         /* Setup flat device-tree pointer */
  80         initial_boot_params = params;
  81
  82         /* Retrieve various informations from the /chosen node of the
  83          * device-tree, including the platform type, initrd location and
  84          * size, and more ...
  85          */
  86         of_scan_flat_dt(early_init_dt_scan_chosen, NULL);
  87
  88         /* Scan memory nodes */
  89         of_scan_flat_dt(early_init_dt_scan_root, NULL);
  90         of_scan_flat_dt(early_init_dt_scan_memory_arch, NULL);
  91 }
  92
  93 void __init device_tree_init(void)
  94 {
  95         unsigned long base, size;
  96
  97         if (!initial_boot_params)
  98                 return;
  99
 100         base = virt_to_phys((void *)initial_boot_params);
 101         size = be32_to_cpu(initial_boot_params->totalsize);
 102
 103         /* Before we do anything, lets reserve the dt blob */
 104         reserve_mem_mach(base, size);
 105
 106         unflatten_device_tree();
 107
 108         /* free the space reserved for the dt blob */
 109         free_mem_mach(base, size);
 110 }