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
  27 static struct of_pdt_ops *of_pdt_prom_ops __initdata;
  28
  29 void __initdata (*of_pdt_build_more)(struct device_node *dp,
  30                 struct device_node ***nextp);
  31
  32 #if defined(CONFIG_SPARC)
  33 unsigned int of_pdt_unique_id __initdata;
  34
  35 #define of_pdt_incr_unique_id(p) do { \
  36         (p)->unique_id = of_pdt_unique_id++; \
  37 } while (0)
  38
  39 static char * __init of_pdt_build_full_name(struct device_node *dp)
  40 {
  41         int len, ourlen, plen;
  42         char *n;
  43
  44         dp->path_component_name = build_path_component(dp);
  45
  46         plen = strlen(dp->parent->full_name);
  47         ourlen = strlen(dp->path_component_name);
  48         len = ourlen + plen + 2;
  49
  50         n = prom_early_alloc(len);
  51         strcpy(n, dp->parent->full_name);
  52         if (!of_node_is_root(dp->parent)) {
  53                 strcpy(n + plen, "/");
  54                 plen++;
  55         }
  56         strcpy(n + plen, dp->path_component_name);
  57
  58         return n;
  59 }
  60
  61 #else /* CONFIG_SPARC */
  62
  63 static inline void of_pdt_incr_unique_id(void *p) { }
  64 static inline void irq_trans_init(struct device_node *dp) { }
  65
  66 static char * __init of_pdt_build_full_name(struct device_node *dp)
  67 {
  68         static int failsafe_id = 0; /* for generating unique names on failure */
  69         char *buf;
  70         int len;
  71
  72         if (of_pdt_prom_ops->pkg2path(dp->phandle, NULL, 0, &len))
  73                 goto failsafe;
  74
  75         buf = prom_early_alloc(len + 1);
  76         if (of_pdt_prom_ops->pkg2path(dp->phandle, buf, len, &len))
  77                 goto failsafe;
  78         return buf;
  79
  80  failsafe:
  81         buf = prom_early_alloc(strlen(dp->parent->full_name) +
  82                                strlen(dp->name) + 16);
  83         sprintf(buf, "%s/%s@unknown%i",
  84                 of_node_is_root(dp->parent) ? "" : dp->parent->full_name,
  85                 dp->name, failsafe_id++);
  86         pr_err("%s: pkg2path failed; assigning %s\n", __func__, buf);
  87         return buf;
  88 }
  89
  90 #endif /* !CONFIG_SPARC */
  91
  92 static struct property * __init of_pdt_build_one_prop(phandle node, char *prev,
  93                                                char *special_name,
  94                                                void *special_val,
  95                                                int special_len)
  96 {
  97         static struct property *tmp = NULL;
  98         struct property *p;
  99         int err;
 100
 101         if (tmp) {
 102                 p = tmp;
 103                 memset(p, 0, sizeof(*p) + 32);
 104                 tmp = NULL;
 105         } else {
 106                 p = prom_early_alloc(sizeof(struct property) + 32);
 107                 of_pdt_incr_unique_id(p);
 108         }
 109
 110         p->name = (char *) (p + 1);
 111         if (special_name) {
 112                 strcpy(p->name, special_name);
 113                 p->length = special_len;
 114                 p->value = prom_early_alloc(special_len);
 115                 memcpy(p->value, special_val, special_len);
 116         } else {
 117                 err = of_pdt_prom_ops->nextprop(node, prev, p->name);
 118                 if (err) {
 119                         tmp = p;
 120                         return NULL;
 121                 }
 122                 p->length = of_pdt_prom_ops->getproplen(node, p->name);
 123                 if (p->length <= 0) {
 124                         p->length = 0;
 125                 } else {
 126                         int len;
 127
 128                         p->value = prom_early_alloc(p->length + 1);
 129                         len = of_pdt_prom_ops->getproperty(node, p->name,
 130                                         p->value, p->length);
 131                         if (len <= 0)
 132                                 p->length = 0;
 133                         ((unsigned char *)p->value)[p->length] = '\0';
 134                 }
 135         }
 136         return p;
 137 }
 138
 139 static struct property * __init of_pdt_build_prop_list(phandle node)
 140 {
 141         struct property *head, *tail;
 142
 143         head = tail = of_pdt_build_one_prop(node, NULL,
 144                                      ".node", &node, sizeof(node));
 145
 146         tail->next = of_pdt_build_one_prop(node, NULL, NULL, NULL, 0);
 147         tail = tail->next;
 148         while(tail) {
 149                 tail->next = of_pdt_build_one_prop(node, tail->name,
 150                                             NULL, NULL, 0);
 151                 tail = tail->next;
 152         }
 153
 154         return head;
 155 }
 156
 157 static char * __init of_pdt_get_one_property(phandle node, const char *name)
 158 {
 159         char *buf = "<NULL>";
 160         int len;
 161
 162         len = of_pdt_prom_ops->getproplen(node, name);
 163         if (len > 0) {
 164                 buf = prom_early_alloc(len);
 165                 len = of_pdt_prom_ops->getproperty(node, name, buf, len);
 166         }
 167
 168         return buf;
 169 }
 170
 171 static struct device_node * __init of_pdt_create_node(phandle node,
 172                                                     struct device_node *parent)
 173 {
 174         struct device_node *dp;
 175
 176         if (!node)
 177                 return NULL;
 178
 179         dp = prom_early_alloc(sizeof(*dp));
 180         of_pdt_incr_unique_id(dp);
 181         dp->parent = parent;
 182
 183         kref_init(&dp->kref);
 184
 185         dp->name = of_pdt_get_one_property(node, "name");
 186         dp->type = of_pdt_get_one_property(node, "device_type");
 187         dp->phandle = node;
 188
 189         dp->properties = of_pdt_build_prop_list(node);
 190
 191         irq_trans_init(dp);
 192
 193         return dp;
 194 }
 195
 196 static struct device_node * __init of_pdt_build_tree(struct device_node *parent,
 197                                                    phandle node,
 198                                                    struct device_node ***nextp)
 199 {
 200         struct device_node *ret = NULL, *prev_sibling = NULL;
 201         struct device_node *dp;
 202
 203         while (1) {
 204                 dp = of_pdt_create_node(node, parent);
 205                 if (!dp)
 206                         break;
 207
 208                 if (prev_sibling)
 209                         prev_sibling->sibling = dp;
 210
 211                 if (!ret)
 212                         ret = dp;
 213                 prev_sibling = dp;
 214
 215                 *(*nextp) = dp;
 216                 *nextp = &dp->allnext;
 217
 218                 dp->full_name = of_pdt_build_full_name(dp);
 219
 220                 dp->child = of_pdt_build_tree(dp,
 221                                 of_pdt_prom_ops->getchild(node), nextp);
 222
 223                 if (of_pdt_build_more)
 224                         of_pdt_build_more(dp, nextp);
 225
 226                 node = of_pdt_prom_ops->getsibling(node);
 227         }
 228
 229         return ret;
 230 }
 231
 232 static void * __init kernel_tree_alloc(u64 size, u64 align)
 233 {
 234         return prom_early_alloc(size);
 235 }
 236
 237 void __init of_pdt_build_devicetree(phandle root_node, struct of_pdt_ops *ops)
 238 {
 239         struct device_node **nextp;
 240
 241         BUG_ON(!ops);
 242         of_pdt_prom_ops = ops;
 243
 244         of_allnodes = of_pdt_create_node(root_node, NULL);
 245 #if defined(CONFIG_SPARC)
 246         of_allnodes->path_component_name = "";
 247 #endif
 248         of_allnodes->full_name = "/";
 249
 250         nextp = &of_allnodes->allnext;
 251         of_allnodes->child = of_pdt_build_tree(of_allnodes,
 252                         of_pdt_prom_ops->getchild(of_allnodes->phandle), &nextp);
 253
 254         /* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */
 255         of_alias_scan(kernel_tree_alloc);
 256 }