drivers/of/pdt.c

   1 /* pdt.c: OF PROM device tree support 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  *  Adapted for multiple architectures by Andres Salomon <dilinger@queued.net>
  11  *
  12  *      This program is free software; you can redistribute it and/or
  13  *      modify it under the terms of the GNU General Public License
  14  *      as published by the Free Software Foundation; either version
  15  *      2 of the License, or (at your option) any later version.
  16  */
  17
  18 #include <linux/kernel.h>
  19 #include <linux/module.h>
  20 #include <linux/errno.h>
  21 #include <linux/mutex.h>
  22 #include <linux/slab.h>
  23 #include <linux/of.h>
  24 #include <linux/of_pdt.h>
  25 #include <asm/prom.h>
  26 #include <asm/oplib.h>
  27
  28 void __initdata (*prom_build_more)(struct device_node *dp,
  29                 struct device_node ***nextp);
  30
  31 #if defined(CONFIG_SPARC)
  32 unsigned int of_pdt_unique_id __initdata;
  33
  34 #define of_pdt_incr_unique_id(p) do { \
  35         (p)->unique_id = of_pdt_unique_id++; \
  36 } while (0)
  37
  38 static inline const char *of_pdt_node_name(struct device_node *dp)
  39 {
  40         return dp->path_component_name;
  41 }
  42
  43 #else
  44
  45 static inline void of_pdt_incr_unique_id(void *p) { }
  46 static inline void irq_trans_init(struct device_node *dp) { }
  47
  48 static inline const char *of_pdt_node_name(struct device_node *dp)
  49 {
  50         return dp->name;
  51 }
  52
  53 #endif /* !CONFIG_SPARC */
  54
  55 static struct property * __init build_one_prop(phandle node, char *prev,
  56                                                char *special_name,
  57                                                void *special_val,
  58                                                int special_len)
  59 {
  60         static struct property *tmp = NULL;
  61         struct property *p;
  62         const char *name;
  63
  64         if (tmp) {
  65                 p = tmp;
  66                 memset(p, 0, sizeof(*p) + 32);
  67                 tmp = NULL;
  68         } else {
  69                 p = prom_early_alloc(sizeof(struct property) + 32);
  70                 of_pdt_incr_unique_id(p);
  71         }
  72
  73         p->name = (char *) (p + 1);
  74         if (special_name) {
  75                 strcpy(p->name, special_name);
  76                 p->length = special_len;
  77                 p->value = prom_early_alloc(special_len);
  78                 memcpy(p->value, special_val, special_len);
  79         } else {
  80                 if (prev == NULL) {
  81                         name = prom_firstprop(node, p->name);
  82                 } else {
  83                         name = prom_nextprop(node, prev, p->name);
  84                 }
  85
  86                 if (!name || strlen(name) == 0) {
  87                         tmp = p;
  88                         return NULL;
  89                 }
  90 #ifdef CONFIG_SPARC32
  91                 strcpy(p->name, name);
  92 #endif
  93                 p->length = prom_getproplen(node, p->name);
  94                 if (p->length <= 0) {
  95                         p->length = 0;
  96                 } else {
  97                         int len;
  98
  99                         p->value = prom_early_alloc(p->length + 1);
 100                         len = prom_getproperty(node, p->name, p->value,
 101                                                p->length);
 102                         if (len <= 0)
 103                                 p->length = 0;
 104                         ((unsigned char *)p->value)[p->length] = '\0';
 105                 }
 106         }
 107         return p;
 108 }
 109
 110 static struct property * __init build_prop_list(phandle node)
 111 {
 112         struct property *head, *tail;
 113
 114         head = tail = build_one_prop(node, NULL,
 115                                      ".node", &node, sizeof(node));
 116
 117         tail->next = build_one_prop(node, NULL, NULL, NULL, 0);
 118         tail = tail->next;
 119         while(tail) {
 120                 tail->next = build_one_prop(node, tail->name,
 121                                             NULL, NULL, 0);
 122                 tail = tail->next;
 123         }
 124
 125         return head;
 126 }
 127
 128 static char * __init get_one_property(phandle node, const char *name)
 129 {
 130         char *buf = "<NULL>";
 131         int len;
 132
 133         len = prom_getproplen(node, name);
 134         if (len > 0) {
 135                 buf = prom_early_alloc(len);
 136                 len = prom_getproperty(node, name, buf, len);
 137         }
 138
 139         return buf;
 140 }
 141
 142 static struct device_node * __init prom_create_node(phandle node,
 143                                                     struct device_node *parent)
 144 {
 145         struct device_node *dp;
 146
 147         if (!node)
 148                 return NULL;
 149
 150         dp = prom_early_alloc(sizeof(*dp));
 151         of_pdt_incr_unique_id(dp);
 152         dp->parent = parent;
 153
 154         kref_init(&dp->kref);
 155
 156         dp->name = get_one_property(node, "name");
 157         dp->type = get_one_property(node, "device_type");
 158         dp->phandle = node;
 159
 160         dp->properties = build_prop_list(node);
 161
 162         irq_trans_init(dp);
 163
 164         return dp;
 165 }
 166
 167 static char * __init build_full_name(struct device_node *dp)
 168 {
 169         int len, ourlen, plen;
 170         char *n;
 171
 172         plen = strlen(dp->parent->full_name);
 173         ourlen = strlen(of_pdt_node_name(dp));
 174         len = ourlen + plen + 2;
 175
 176         n = prom_early_alloc(len);
 177         strcpy(n, dp->parent->full_name);
 178         if (!of_node_is_root(dp->parent)) {
 179                 strcpy(n + plen, "/");
 180                 plen++;
 181         }
 182         strcpy(n + plen, of_pdt_node_name(dp));
 183
 184         return n;
 185 }
 186
 187 static struct device_node * __init prom_build_tree(struct device_node *parent,
 188                                                    phandle node,
 189                                                    struct device_node ***nextp)
 190 {
 191         struct device_node *ret = NULL, *prev_sibling = NULL;
 192         struct device_node *dp;
 193
 194         while (1) {
 195                 dp = prom_create_node(node, parent);
 196                 if (!dp)
 197                         break;
 198
 199                 if (prev_sibling)
 200                         prev_sibling->sibling = dp;
 201
 202                 if (!ret)
 203                         ret = dp;
 204                 prev_sibling = dp;
 205
 206                 *(*nextp) = dp;
 207                 *nextp = &dp->allnext;
 208
 209 #if defined(CONFIG_SPARC)
 210                 dp->path_component_name = build_path_component(dp);
 211 #endif
 212                 dp->full_name = build_full_name(dp);
 213
 214                 dp->child = prom_build_tree(dp, prom_getchild(node), nextp);
 215
 216                 if (prom_build_more)
 217                         prom_build_more(dp, nextp);
 218
 219                 node = prom_getsibling(node);
 220         }
 221
 222         return ret;
 223 }
 224
 225 void __init of_pdt_build_devicetree(phandle root_node)
 226 {
 227         struct device_node **nextp;
 228
 229         allnodes = prom_create_node(root_node, NULL);
 230 #if defined(CONFIG_SPARC)
 231         allnodes->path_component_name = "";
 232 #endif
 233         allnodes->full_name = "/";
 234
 235         nextp = &allnodes->allnext;
 236         allnodes->child = prom_build_tree(allnodes,
 237                                           prom_getchild(allnodes->phandle),
 238                                           &nextp);
 239 }