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 u64 __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
  49 {
  50         return virt_to_phys(
  51                 __alloc_bootmem(size, align, __pa(MAX_DMA_ADDRESS))
  52                 );
  53 }
  54
  55 #ifdef CONFIG_BLK_DEV_INITRD
  56 void __init early_init_dt_setup_initrd_arch(unsigned long start,
  57                                             unsigned long end)
  58 {
  59         initrd_start = (unsigned long)__va(start);
  60         initrd_end = (unsigned long)__va(end);
  61         initrd_below_start_ok = 1;
  62 }
  63 #endif
  64
  65 /*
  66  * irq_create_of_mapping - Hook to resolve OF irq specifier into a Linux irq#
  67  *
  68  * Currently the mapping mechanism is trivial; simple flat hwirq numbers are
  69  * mapped 1:1 onto Linux irq numbers.  Cascaded irq controllers are not
  70  * supported.
  71  */
  72 unsigned int irq_create_of_mapping(struct device_node *controller,
  73                                    const u32 *intspec, unsigned int intsize)
  74 {
  75         return intspec[0];
  76 }
  77 EXPORT_SYMBOL_GPL(irq_create_of_mapping);
  78
  79 void __init early_init_devtree(void *params)
  80 {
  81         /* Setup flat device-tree pointer */
  82         initial_boot_params = params;
  83
  84         /* Retrieve various informations from the /chosen node of the
  85          * device-tree, including the platform type, initrd location and
  86          * size, and more ...
  87          */
  88         of_scan_flat_dt(early_init_dt_scan_chosen, NULL);
  89
  90         /* Scan memory nodes */
  91         of_scan_flat_dt(early_init_dt_scan_root, NULL);
  92         of_scan_flat_dt(early_init_dt_scan_memory_arch, NULL);
  93 }
  94
  95 void __init device_tree_init(void)
  96 {
  97         unsigned long base, size;
  98
  99         if (!initial_boot_params)
 100                 return;
 101
 102         base = virt_to_phys((void *)initial_boot_params);
 103         size = initial_boot_params->totalsize;
 104
 105         /* Before we do anything, lets reserve the dt blob */
 106         reserve_mem_mach(base, size);
 107
 108         unflatten_device_tree();
 109
 110         /* free the space reserved for the dt blob */
 111         free_mem_mach(base, size);
 112 }