arch/sparc/kernel/prom_common.c

   1 /* prom_common.c: OF device tree support common code.
   2  *
   3  * Paul Mackerras       August 1996.
   4  * Copyright (C) 1996-2005 Paul Mackerras.
   5  *
   6  *  Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
   7  *    {engebret|bergner}@us.ibm.com
   8  *
   9  *  Adapted for sparc by David S. Miller davem@davemloft.net
  10  *
  11  *      This program is free software; you can redistribute it and/or
  12  *      modify it under the terms of the GNU General Public License
  13  *      as published by the Free Software Foundation; either version
  14  *      2 of the License, or (at your option) any later version.
  15  */
  16
  17 #include <linux/kernel.h>
  18 #include <linux/module.h>
  19 #include <linux/errno.h>
  20 #include <linux/mutex.h>
  21 #include <linux/slab.h>
  22 #include <linux/of.h>
  23 #include <asm/prom.h>
  24 #include <asm/oplib.h>
  25
  26 #include "prom.h"
  27
  28 struct device_node *of_find_node_by_phandle(phandle handle)
  29 {
  30         struct device_node *np;
  31
  32         for (np = allnodes; np; np = np->allnext)
  33                 if (np->node == handle)
  34                         break;
  35
  36         return np;
  37 }
  38 EXPORT_SYMBOL(of_find_node_by_phandle);
  39
  40 int of_getintprop_default(struct device_node *np, const char *name, int def)
  41 {
  42         struct property *prop;
  43         int len;
  44
  45         prop = of_find_property(np, name, &len);
  46         if (!prop || len != 4)
  47                 return def;
  48
  49         return *(int *) prop->value;
  50 }
  51 EXPORT_SYMBOL(of_getintprop_default);
  52
  53 DEFINE_MUTEX(of_set_property_mutex);
  54 EXPORT_SYMBOL(of_set_property_mutex);
  55
  56 int of_set_property(struct device_node *dp, const char *name, void *val, int len)
  57 {
  58         struct property **prevp;
  59         void *new_val;
  60         int err;
  61
  62         new_val = kmalloc(len, GFP_KERNEL);
  63         if (!new_val)
  64                 return -ENOMEM;
  65
  66         memcpy(new_val, val, len);
  67
  68         err = -ENODEV;
  69
  70         write_lock(&devtree_lock);
  71         prevp = &dp->properties;
  72         while (*prevp) {
  73                 struct property *prop = *prevp;
  74
  75                 if (!strcasecmp(prop->name, name)) {
  76                         void *old_val = prop->value;
  77                         int ret;
  78
  79                         mutex_lock(&of_set_property_mutex);
  80                         ret = prom_setprop(dp->node, name, val, len);
  81                         mutex_unlock(&of_set_property_mutex);
  82
  83                         err = -EINVAL;
  84                         if (ret >= 0) {
  85                                 prop->value = new_val;
  86                                 prop->length = len;
  87
  88                                 if (OF_IS_DYNAMIC(prop))
  89                                         kfree(old_val);
  90
  91                                 OF_MARK_DYNAMIC(prop);
  92
  93                                 err = 0;
  94                         }
  95                         break;
  96                 }
  97                 prevp = &(*prevp)->next;
  98         }
  99         write_unlock(&devtree_lock);
 100
 101         /* XXX Upate procfs if necessary... */
 102
 103         return err;
 104 }
 105 EXPORT_SYMBOL(of_set_property);
 106
 107 int of_find_in_proplist(const char *list, const char *match, int len)
 108 {
 109         while (len > 0) {
 110                 int l;
 111
 112                 if (!strcmp(list, match))
 113                         return 1;
 114                 l = strlen(list) + 1;
 115                 list += l;
 116                 len -= l;
 117         }
 118         return 0;
 119 }
 120 EXPORT_SYMBOL(of_find_in_proplist);
 121
 122 unsigned int prom_unique_id;
 123
 124 static struct property * __init build_one_prop(phandle node, char *prev,
 125                                                char *special_name,
 126                                                void *special_val,
 127                                                int special_len)
 128 {
 129         static struct property *tmp = NULL;
 130         struct property *p;
 131         const char *name;
 132
 133         if (tmp) {
 134                 p = tmp;
 135                 memset(p, 0, sizeof(*p) + 32);
 136                 tmp = NULL;
 137         } else {
 138                 p = prom_early_alloc(sizeof(struct property) + 32);
 139                 p->unique_id = prom_unique_id++;
 140         }
 141
 142         p->name = (char *) (p + 1);
 143         if (special_name) {
 144                 strcpy(p->name, special_name);
 145                 p->length = special_len;
 146                 p->value = prom_early_alloc(special_len);
 147                 memcpy(p->value, special_val, special_len);
 148         } else {
 149 #ifdef CONFIG_SPARC32
 150                 if (prev == NULL) {
 151                         name = prom_firstprop(node, NULL);
 152                 } else {
 153                         name = prom_nextprop(node, prev, NULL);
 154                 }
 155 #else
 156                 if (prev == NULL) {
 157                         prom_firstprop(node, p->name);
 158                 } else {
 159                         prom_nextprop(node, prev, p->name);
 160                 }
 161                 name = p->name;
 162 #endif
 163                 if (strlen(name) == 0) {
 164                         tmp = p;
 165                         return NULL;
 166                 }
 167 #ifdef CONFIG_SPARC32
 168                 strcpy(p->name, name);
 169 #endif
 170                 p->length = prom_getproplen(node, p->name);
 171                 if (p->length <= 0) {
 172                         p->length = 0;
 173                 } else {
 174                         int len;
 175
 176                         p->value = prom_early_alloc(p->length + 1);
 177                         len = prom_getproperty(node, p->name, p->value,
 178                                                p->length);
 179                         if (len <= 0)
 180                                 p->length = 0;
 181                         ((unsigned char *)p->value)[p->length] = '\0';
 182                 }
 183         }
 184         return p;
 185 }
 186
 187 static struct property * __init build_prop_list(phandle node)
 188 {
 189         struct property *head, *tail;
 190
 191         head = tail = build_one_prop(node, NULL,
 192                                      ".node", &node, sizeof(node));
 193
 194         tail->next = build_one_prop(node, NULL, NULL, NULL, 0);
 195         tail = tail->next;
 196         while(tail) {
 197                 tail->next = build_one_prop(node, tail->name,
 198                                             NULL, NULL, 0);
 199                 tail = tail->next;
 200         }
 201
 202         return head;
 203 }
 204
 205 static char * __init get_one_property(phandle node, const char *name)
 206 {
 207         char *buf = "<NULL>";
 208         int len;
 209
 210         len = prom_getproplen(node, name);
 211         if (len > 0) {
 212                 buf = prom_early_alloc(len);
 213                 len = prom_getproperty(node, name, buf, len);
 214         }
 215
 216         return buf;
 217 }
 218
 219 struct device_node * __init prom_create_node(phandle node,
 220                                              struct device_node *parent)
 221 {
 222         struct device_node *dp;
 223
 224         if (!node)
 225                 return NULL;
 226
 227         dp = prom_early_alloc(sizeof(*dp));
 228         dp->unique_id = prom_unique_id++;
 229         dp->parent = parent;
 230
 231         kref_init(&dp->kref);
 232
 233         dp->name = get_one_property(node, "name");
 234         dp->type = get_one_property(node, "device_type");
 235         dp->node = node;
 236
 237         /* Build interrupts later... */
 238
 239         dp->properties = build_prop_list(node);
 240
 241         return dp;
 242 }
 243
 244 static char * __init build_full_name(struct device_node *dp)
 245 {
 246         int len, ourlen, plen;
 247         char *n;
 248
 249         plen = strlen(dp->parent->full_name);
 250         ourlen = strlen(dp->path_component_name);
 251         len = ourlen + plen + 2;
 252
 253         n = prom_early_alloc(len);
 254         strcpy(n, dp->parent->full_name);
 255         if (!is_root_node(dp->parent)) {
 256                 strcpy(n + plen, "/");
 257                 plen++;
 258         }
 259         strcpy(n + plen, dp->path_component_name);
 260
 261         return n;
 262 }
 263
 264 struct device_node * __init prom_build_tree(struct device_node *parent,
 265                                             phandle node,
 266                                             struct device_node ***nextp)
 267 {
 268         struct device_node *ret = NULL, *prev_sibling = NULL;
 269         struct device_node *dp;
 270
 271         while (1) {
 272                 dp = prom_create_node(node, parent);
 273                 if (!dp)
 274                         break;
 275
 276                 if (prev_sibling)
 277                         prev_sibling->sibling = dp;
 278
 279                 if (!ret)
 280                         ret = dp;
 281                 prev_sibling = dp;
 282
 283                 *(*nextp) = dp;
 284                 *nextp = &dp->allnext;
 285
 286                 dp->path_component_name = build_path_component(dp);
 287                 dp->full_name = build_full_name(dp);
 288
 289                 dp->child = prom_build_tree(dp, prom_getchild(node), nextp);
 290
 291                 node = prom_getsibling(node);
 292         }
 293
 294         return ret;
 295 }