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
  26 static struct of_pdt_ops *of_pdt_prom_ops __initdata;
  27
  28 void __initdata (*of_pdt_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 char * __init of_pdt_build_full_name(struct device_node *dp)
  39 {
  40         int len, ourlen, plen;
  41         char *n;
  42
  43         dp->path_component_name = build_path_component(dp);
  44
  45         plen = strlen(dp->parent->full_name);
  46         ourlen = strlen(dp->path_component_name);
  47         len = ourlen + plen + 2;
  48
  49         n = prom_early_alloc(len);
  50         strcpy(n, dp->parent->full_name);
  51         if (!of_node_is_root(dp->parent)) {
  52                 strcpy(n + plen, "/");
  53                 plen++;
  54         }
  55         strcpy(n + plen, dp->path_component_name);
  56
  57         return n;
  58 }
  59
  60 #else /* CONFIG_SPARC */
  61
  62 static inline void of_pdt_incr_unique_id(void *p) { }
  63 static inline void irq_trans_init(struct device_node *dp) { }
  64
  65 static char * __init of_pdt_build_full_name(struct device_node *dp)
  66 {
  67         static int failsafe_id = 0; /* for generating unique names on failure */
  68         char *buf;
  69         int len;
  70
  71         if (of_pdt_prom_ops->pkg2path(dp->phandle, NULL, 0, &len))
  72                 goto failsafe;
  73
  74         buf = prom_early_alloc(len + 1);
  75         if (of_pdt_prom_ops->pkg2path(dp->phandle, buf, len, &len))
  76                 goto failsafe;
  77         return buf;
  78
  79  failsafe:
  80         buf = prom_early_alloc(strlen(dp->parent->full_name) +
  81                                strlen(dp->name) + 16);
  82         sprintf(buf, "%s/%s@unknown%i",
  83                 of_node_is_root(dp->parent) ? "" : dp->parent->full_name,
  84                 dp->name, failsafe_id++);
  85         pr_err("%s: pkg2path failed; assigning %s\n", __func__, buf);
  86         return buf;
  87 }
  88
  89 #endif /* !CONFIG_SPARC */
  90
  91 static struct property * __init of_pdt_build_one_prop(phandle node, char *prev,
  92                                                char *special_name,
  93                                                void *special_val,
  94                                                int special_len)
  95 {
  96         static struct property *tmp = NULL;
  97         struct property *p;
  98         int err;
  99
 100         if (tmp) {
 101                 p = tmp;
 102                 memset(p, 0, sizeof(*p) + 32);
 103                 tmp = NULL;
 104         } else {
 105                 p = prom_early_alloc(sizeof(struct property) + 32);
 106                 of_pdt_incr_unique_id(p);
 107         }
 108
 109         p->name = (char *) (p + 1);
 110         if (special_name) {
 111                 strcpy(p->name, special_name);
 112                 p->length = special_len;
 113                 p->value = prom_early_alloc(special_len);
 114                 memcpy(p->value, special_val, special_len);
 115         } else {
 116                 err = of_pdt_prom_ops->nextprop(node, prev, p->name);
 117                 if (err) {
 118                         tmp = p;
 119                         return NULL;
 120                 }
 121                 p->length = of_pdt_prom_ops->getproplen(node, p->name);
 122                 if (p->length <= 0) {
 123                         p->length = 0;
 124                 } else {
 125                         int len;
 126
 127                         p->value = prom_early_alloc(p->length + 1);
 128                         len = of_pdt_prom_ops->getproperty(node, p->name,
 129                                         p->value, p->length);
 130                         if (len <= 0)
 131                                 p->length = 0;
 132                         ((unsigned char *)p->value)[p->length] = '\0';
 133                 }
 134         }
 135         return p;
 136 }
 137
 138 static struct property * __init of_pdt_build_prop_list(phandle node)
 139 {
 140         struct property *head, *tail;
 141
 142         head = tail = of_pdt_build_one_prop(node, NULL,
 143                                      ".node", &node, sizeof(node));
 144
 145         tail->next = of_pdt_build_one_prop(node, NULL, NULL, NULL, 0);
 146         tail = tail->next;
 147         while(tail) {
 148                 tail->next = of_pdt_build_one_prop(node, tail->name,
 149                                             NULL, NULL, 0);
 150                 tail = tail->next;
 151         }
 152
 153         return head;
 154 }
 155
 156 static char * __init of_pdt_get_one_property(phandle node, const char *name)
 157 {
 158         char *buf = "<NULL>";
 159         int len;
 160
 161         len = of_pdt_prom_ops->getproplen(node, name);
 162         if (len > 0) {
 163                 buf = prom_early_alloc(len);
 164                 len = of_pdt_prom_ops->getproperty(node, name, buf, len);
 165         }
 166
 167         return buf;
 168 }
 169
 170 static struct device_node * __init of_pdt_create_node(phandle node,
 171                                                     struct device_node *parent)
 172 {
 173         struct device_node *dp;
 174
 175         if (!node)
 176                 return NULL;
 177
 178         dp = prom_early_alloc(sizeof(*dp));
 179         of_node_init(dp);
 180         of_pdt_incr_unique_id(dp);
 181         dp->parent = parent;
 182
 183         dp->name = of_pdt_get_one_property(node, "name");
 184         dp->type = of_pdt_get_one_property(node, "device_type");
 185         dp->phandle = node;
 186
 187         dp->properties = of_pdt_build_prop_list(node);
 188
 189         irq_trans_init(dp);
 190
 191         return dp;
 192 }
 193
 194 static struct device_node * __init of_pdt_build_tree(struct device_node *parent,
 195                                                    phandle node,
 196                                                    struct device_node ***nextp)
 197 {
 198         struct device_node *ret = NULL, *prev_sibling = NULL;
 199         struct device_node *dp;
 200
 201         while (1) {
 202                 dp = of_pdt_create_node(node, parent);
 203                 if (!dp)
 204                         break;
 205
 206                 if (prev_sibling)
 207                         prev_sibling->sibling = dp;
 208
 209                 if (!ret)
 210                         ret = dp;
 211                 prev_sibling = dp;
 212
 213                 *(*nextp) = dp;
 214                 *nextp = &dp->allnext;
 215
 216                 dp->full_name = of_pdt_build_full_name(dp);
 217
 218                 dp->child = of_pdt_build_tree(dp,
 219                                 of_pdt_prom_ops->getchild(node), nextp);
 220
 221                 if (of_pdt_build_more)
 222                         of_pdt_build_more(dp, nextp);
 223
 224                 node = of_pdt_prom_ops->getsibling(node);
 225         }
 226
 227         return ret;
 228 }
 229
 230 static void * __init kernel_tree_alloc(u64 size, u64 align)
 231 {
 232         return prom_early_alloc(size);
 233 }
 234
 235 void __init of_pdt_build_devicetree(phandle root_node, struct of_pdt_ops *ops)
 236 {
 237         struct device_node **nextp;
 238
 239         BUG_ON(!ops);
 240         of_pdt_prom_ops = ops;
 241
 242         of_allnodes = of_pdt_create_node(root_node, NULL);
 243 #if defined(CONFIG_SPARC)
 244         of_allnodes->path_component_name = "";
 245 #endif
 246         of_allnodes->full_name = "/";
 247
 248         nextp = &of_allnodes->allnext;
 249         of_allnodes->child = of_pdt_build_tree(of_allnodes,
 250                         of_pdt_prom_ops->getchild(of_allnodes->phandle), &nextp);
 251
 252         /* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */
 253         of_alias_scan(kernel_tree_alloc);
 254 }