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_console_device;
  29 EXPORT_SYMBOL(of_console_device);
  30
  31 char *of_console_path;
  32 EXPORT_SYMBOL(of_console_path);
  33
  34 char *of_console_options;
  35 EXPORT_SYMBOL(of_console_options);
  36
  37 struct device_node *of_find_node_by_phandle(phandle handle)
  38 {
  39         struct device_node *np;
  40
  41         for (np = allnodes; np; np = np->allnext)
  42                 if (np->node == handle)
  43                         break;
  44
  45         return np;
  46 }
  47 EXPORT_SYMBOL(of_find_node_by_phandle);
  48
  49 int of_getintprop_default(struct device_node *np, const char *name, int def)
  50 {
  51         struct property *prop;
  52         int len;
  53
  54         prop = of_find_property(np, name, &len);
  55         if (!prop || len != 4)
  56                 return def;
  57
  58         return *(int *) prop->value;
  59 }
  60 EXPORT_SYMBOL(of_getintprop_default);
  61
  62 DEFINE_MUTEX(of_set_property_mutex);
  63 EXPORT_SYMBOL(of_set_property_mutex);
  64
  65 int of_set_property(struct device_node *dp, const char *name, void *val, int len)
  66 {
  67         struct property **prevp;
  68         void *new_val;
  69         int err;
  70
  71         new_val = kmalloc(len, GFP_KERNEL);
  72         if (!new_val)
  73                 return -ENOMEM;
  74
  75         memcpy(new_val, val, len);
  76
  77         err = -ENODEV;
  78
  79         write_lock(&devtree_lock);
  80         prevp = &dp->properties;
  81         while (*prevp) {
  82                 struct property *prop = *prevp;
  83
  84                 if (!strcasecmp(prop->name, name)) {
  85                         void *old_val = prop->value;
  86                         int ret;
  87
  88                         mutex_lock(&of_set_property_mutex);
  89                         ret = prom_setprop(dp->node, name, val, len);
  90                         mutex_unlock(&of_set_property_mutex);
  91
  92                         err = -EINVAL;
  93                         if (ret >= 0) {
  94                                 prop->value = new_val;
  95                                 prop->length = len;
  96
  97                                 if (OF_IS_DYNAMIC(prop))
  98                                         kfree(old_val);
  99
 100                                 OF_MARK_DYNAMIC(prop);
 101
 102                                 err = 0;
 103                         }
 104                         break;
 105                 }
 106                 prevp = &(*prevp)->next;
 107         }
 108         write_unlock(&devtree_lock);
 109
 110         /* XXX Upate procfs if necessary... */
 111
 112         return err;
 113 }
 114 EXPORT_SYMBOL(of_set_property);
 115
 116 int of_find_in_proplist(const char *list, const char *match, int len)
 117 {
 118         while (len > 0) {
 119                 int l;
 120
 121                 if (!strcmp(list, match))
 122                         return 1;
 123                 l = strlen(list) + 1;
 124                 list += l;
 125                 len -= l;
 126         }
 127         return 0;
 128 }
 129 EXPORT_SYMBOL(of_find_in_proplist);
 130
 131 unsigned int prom_unique_id;
 132
 133 static struct property * __init build_one_prop(phandle node, char *prev,
 134                                                char *special_name,
 135                                                void *special_val,
 136                                                int special_len)
 137 {
 138         static struct property *tmp = NULL;
 139         struct property *p;
 140         const char *name;
 141
 142         if (tmp) {
 143                 p = tmp;
 144                 memset(p, 0, sizeof(*p) + 32);
 145                 tmp = NULL;
 146         } else {
 147                 p = prom_early_alloc(sizeof(struct property) + 32);
 148                 p->unique_id = prom_unique_id++;
 149         }
 150
 151         p->name = (char *) (p + 1);
 152         if (special_name) {
 153                 strcpy(p->name, special_name);
 154                 p->length = special_len;
 155                 p->value = prom_early_alloc(special_len);
 156                 memcpy(p->value, special_val, special_len);
 157         } else {
 158                 if (prev == NULL) {
 159                         name = prom_firstprop(node, p->name);
 160                 } else {
 161                         name = prom_nextprop(node, prev, p->name);
 162                 }
 163
 164                 if (strlen(name) == 0) {
 165                         tmp = p;
 166                         return NULL;
 167                 }
 168 #ifdef CONFIG_SPARC32
 169                 strcpy(p->name, name);
 170 #endif
 171                 p->length = prom_getproplen(node, p->name);
 172                 if (p->length <= 0) {
 173                         p->length = 0;
 174                 } else {
 175                         int len;
 176
 177                         p->value = prom_early_alloc(p->length + 1);
 178                         len = prom_getproperty(node, p->name, p->value,
 179                                                p->length);
 180                         if (len <= 0)
 181                                 p->length = 0;
 182                         ((unsigned char *)p->value)[p->length] = '\0';
 183                 }
 184         }
 185         return p;
 186 }
 187
 188 static struct property * __init build_prop_list(phandle node)
 189 {
 190         struct property *head, *tail;
 191
 192         head = tail = build_one_prop(node, NULL,
 193                                      ".node", &node, sizeof(node));
 194
 195         tail->next = build_one_prop(node, NULL, NULL, NULL, 0);
 196         tail = tail->next;
 197         while(tail) {
 198                 tail->next = build_one_prop(node, tail->name,
 199                                             NULL, NULL, 0);
 200                 tail = tail->next;
 201         }
 202
 203         return head;
 204 }
 205
 206 static char * __init get_one_property(phandle node, const char *name)
 207 {
 208         char *buf = "<NULL>";
 209         int len;
 210
 211         len = prom_getproplen(node, name);
 212         if (len > 0) {
 213                 buf = prom_early_alloc(len);
 214                 len = prom_getproperty(node, name, buf, len);
 215         }
 216
 217         return buf;
 218 }
 219
 220 static struct device_node * __init prom_create_node(phandle node,
 221                                                     struct device_node *parent)
 222 {
 223         struct device_node *dp;
 224
 225         if (!node)
 226                 return NULL;
 227
 228         dp = prom_early_alloc(sizeof(*dp));
 229         dp->unique_id = prom_unique_id++;
 230         dp->parent = parent;
 231
 232         kref_init(&dp->kref);
 233
 234         dp->name = get_one_property(node, "name");
 235         dp->type = get_one_property(node, "device_type");
 236         dp->node = node;
 237
 238         dp->properties = build_prop_list(node);
 239
 240         irq_trans_init(dp);
 241
 242         return dp;
 243 }
 244
 245 static char * __init build_full_name(struct device_node *dp)
 246 {
 247         int len, ourlen, plen;
 248         char *n;
 249
 250         plen = strlen(dp->parent->full_name);
 251         ourlen = strlen(dp->path_component_name);
 252         len = ourlen + plen + 2;
 253
 254         n = prom_early_alloc(len);
 255         strcpy(n, dp->parent->full_name);
 256         if (!is_root_node(dp->parent)) {
 257                 strcpy(n + plen, "/");
 258                 plen++;
 259         }
 260         strcpy(n + plen, dp->path_component_name);
 261
 262         return n;
 263 }
 264
 265 static struct device_node * __init prom_build_tree(struct device_node *parent,
 266                                                    phandle node,
 267                                                    struct device_node ***nextp)
 268 {
 269         struct device_node *ret = NULL, *prev_sibling = NULL;
 270         struct device_node *dp;
 271
 272         while (1) {
 273                 dp = prom_create_node(node, parent);
 274                 if (!dp)
 275                         break;
 276
 277                 if (prev_sibling)
 278                         prev_sibling->sibling = dp;
 279
 280                 if (!ret)
 281                         ret = dp;
 282                 prev_sibling = dp;
 283
 284                 *(*nextp) = dp;
 285                 *nextp = &dp->allnext;
 286
 287                 dp->path_component_name = build_path_component(dp);
 288                 dp->full_name = build_full_name(dp);
 289
 290                 dp->child = prom_build_tree(dp, prom_getchild(node), nextp);
 291
 292                 node = prom_getsibling(node);
 293         }
 294
 295         return ret;
 296 }
 297
 298 unsigned int prom_early_allocated __initdata;
 299
 300 void __init prom_build_devicetree(void)
 301 {
 302         struct device_node **nextp;
 303
 304         allnodes = prom_create_node(prom_root_node, NULL);
 305         allnodes->path_component_name = "";
 306         allnodes->full_name = "/";
 307
 308         nextp = &allnodes->allnext;
 309         allnodes->child = prom_build_tree(allnodes,
 310                                           prom_getchild(allnodes->node),
 311                                           &nextp);
 312         of_console_init();
 313
 314         printk("PROM: Built device tree with %u bytes of memory.\n",
 315                prom_early_allocated);
 316 }