--- /dev/null
+/*
+ * Procedures for creating, accessing and interpreting the device tree.
+ *
+ * Paul Mackerras August 1996.
+ * Copyright (C) 1996-2005 Paul Mackerras.
+ *
+ * Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
+ * {engebret|bergner}@us.ibm.com
+ *
+ * Adapted for sparc64 by David S. Miller davem@davemloft.net
+ *
+ * Adapter for i386/OLPC by Andres Salomon <dilinger@debian.org>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/bootmem.h>
+#include <linux/module.h>
+#include <asm/prom.h>
+#include <asm/ofw.h>
+
+/*
+ * XXX: This is very much a stub; right now we're keeping 2 device trees
+ * in memory (one for promfs, and one here). That will not remain
+ * for long!
+ */
+
+static struct device_node *allnodes;
+
+/* use when traversing tree through the allnext, child, sibling,
+ * or parent members of struct device_node.
+ */
+static DEFINE_RWLOCK(devtree_lock);
+
+int of_device_is_compatible(const struct device_node *device,
+ const char *compat)
+{
+ const char* cp;
+ int cplen, l;
+
+ cp = of_get_property(device, "compatible", &cplen);
+ if (cp == NULL)
+ return 0;
+ while (cplen > 0) {
+ if (strncmp(cp, compat, strlen(compat)) == 0)
+ return 1;
+ l = strlen(cp) + 1;
+ cp += l;
+ cplen -= l;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(of_device_is_compatible);
+
+struct device_node *of_get_parent(const struct device_node *node)
+{
+ struct device_node *np;
+
+ if (!node)
+ return NULL;
+
+ np = node->parent;
+
+ return np;
+}
+EXPORT_SYMBOL(of_get_parent);
+
+struct device_node *of_get_next_child(const struct device_node *node,
+ struct device_node *prev)
+{
+ struct device_node *next;
+
+ next = prev ? prev->sibling : node->child;
+ for (; next != 0; next = next->sibling) {
+ break;
+ }
+
+ return next;
+}
+EXPORT_SYMBOL(of_get_next_child);
+
+struct device_node *of_find_node_by_path(const char *path)
+{
+ struct device_node *np = allnodes;
+
+ for (; np != 0; np = np->allnext) {
+ if (np->full_name != 0 && strcmp(np->full_name, path) == 0)
+ break;
+ }
+
+ return np;
+}
+EXPORT_SYMBOL(of_find_node_by_path);
+
+struct device_node *of_find_node_by_phandle(phandle handle)
+{
+ struct device_node *np;
+
+ for (np = allnodes; np != 0; np = np->allnext)
+ if (np->node == handle)
+ break;
+
+ return np;
+}
+EXPORT_SYMBOL(of_find_node_by_phandle);
+
+struct device_node *of_find_node_by_name(struct device_node *from,
+ const char *name)
+{
+ struct device_node *np;
+
+ np = from ? from->allnext : allnodes;
+ for (; np != NULL; np = np->allnext)
+ if (np->name != NULL && strcmp(np->name, name) == 0)
+ break;
+
+ return np;
+}
+EXPORT_SYMBOL(of_find_node_by_name);
+
+struct device_node *of_find_node_by_type(struct device_node *from,
+ const char *type)
+{
+ struct device_node *np;
+
+ np = from ? from->allnext : allnodes;
+ for (; np != 0; np = np->allnext)
+ if (np->type != 0 && strcmp(np->type, type) == 0)
+ break;
+
+ return np;
+}
+EXPORT_SYMBOL(of_find_node_by_type);
+
+struct device_node *of_find_compatible_node(struct device_node *from,
+ const char *type, const char *compatible)
+{
+ struct device_node *np;
+
+ np = from ? from->allnext : allnodes;
+ for (; np != 0; np = np->allnext) {
+ if (type != NULL
+ && !(np->type != 0 && strcmp(np->type, type) == 0))
+ continue;
+ if (of_device_is_compatible(np, compatible))
+ break;
+ }
+
+ return np;
+}
+EXPORT_SYMBOL(of_find_compatible_node);
+
+struct property *of_find_property(const struct device_node *np,
+ const char *name,
+ int *lenp)
+{
+ struct property *pp;
+
+ for (pp = np->properties; pp != 0; pp = pp->next) {
+ if (strcasecmp(pp->name, name) == 0) {
+ if (lenp != 0)
+ *lenp = pp->length;
+ break;
+ }
+ }
+ return pp;
+}
+EXPORT_SYMBOL(of_find_property);
+
+/*
+ * Find a property with a given name for a given node
+ * and return the value.
+ */
+const void *of_get_property(const struct device_node *np, const char *name,
+ int *lenp)
+{
+ struct property *pp = of_find_property(np,name,lenp);
+ return pp ? pp->value : NULL;
+}
+EXPORT_SYMBOL(of_get_property);
+
+int of_getintprop_default(struct device_node *np, const char *name, int def)
+{
+ struct property *prop;
+ int len;
+
+ prop = of_find_property(np, name, &len);
+ if (!prop || len != 4)
+ return def;
+
+ return *(int *) prop->value;
+}
+EXPORT_SYMBOL(of_getintprop_default);
+
+int of_n_addr_cells(struct device_node *np)
+{
+ const int* ip;
+ do {
+ if (np->parent)
+ np = np->parent;
+ ip = of_get_property(np, "#address-cells", NULL);
+ if (ip != NULL)
+ return *ip;
+ } while (np->parent);
+ /* No #address-cells property for the root node, default to 2 */
+ return 2;
+}
+EXPORT_SYMBOL(of_n_addr_cells);
+
+int of_n_size_cells(struct device_node *np)
+{
+ const int* ip;
+ do {
+ if (np->parent)
+ np = np->parent;
+ ip = of_get_property(np, "#size-cells", NULL);
+ if (ip != NULL)
+ return *ip;
+ } while (np->parent);
+ /* No #size-cells property for the root node, default to 1 */
+ return 1;
+}
+EXPORT_SYMBOL(of_n_size_cells);
+
+int of_set_property(struct device_node *dp, const char *name, void *val, int len)
+{
+ return -EIO;
+}
+EXPORT_SYMBOL(of_set_property);
+
+static unsigned int prom_early_allocated;
+
+static void * __init prom_early_alloc(unsigned long size)
+{
+ void *ret;
+
+ ret = kmalloc(size, GFP_KERNEL);
+ if (ret != NULL)
+ memset(ret, 0, size);
+ else
+ printk(KERN_ERR "ACK! couldn't allocate prom memory!\n");
+
+ prom_early_allocated += size;
+
+ return ret;
+}
+
+static int is_root_node(const struct device_node *dp)
+{
+ if (!dp)
+ return 0;
+
+ return (dp->parent == NULL);
+}
+
+static char * __init build_path_component(struct device_node *dp)
+{
+ int pathlen;
+ char *n, *i;
+
+ if (ofw("package-to-path", 3, 1, dp->node, NULL, 0, &pathlen)) {
+ printk(KERN_ERR "PROM: unable to get path name from OFW!\n");
+ return "ERROR";
+ }
+ n = prom_early_alloc(pathlen + 1);
+ if (ofw("package-to-path", 3, 1, dp->node, n, pathlen+1, &pathlen))
+ printk(KERN_ERR "PROM: unable to get path name from OFW\n");
+
+ if ((i = strrchr(n, '/')))
+ n = ++i; /* we only want the file name */
+ return n;
+}
+
+static char * __init build_full_name(struct device_node *dp)
+{
+ int len, ourlen, plen;
+ char *n;
+
+ plen = strlen(dp->parent->full_name);
+ ourlen = strlen(dp->path_component_name);
+ len = ourlen + plen + 2;
+
+ n = prom_early_alloc(len);
+ strcpy(n, dp->parent->full_name);
+ if (!is_root_node(dp->parent)) {
+ strcpy(n + plen, "/");
+ plen++;
+ }
+ strcpy(n + plen, dp->path_component_name);
+
+ return n;
+}
+
+static struct property * __init build_one_prop(phandle node, char *prev, char *special_name, void *special_val, int special_len)
+{
+ static struct property *tmp = NULL;
+ struct property *p;
+
+ if (tmp) {
+ p = tmp;
+ memset(p, 0, sizeof(*p) + 32);
+ tmp = NULL;
+ } else {
+ p = prom_early_alloc(sizeof(struct property) + 32);
+ }
+
+ p->name = (char *) (p + 1);
+ if (special_name) {
+ strcpy(p->name, special_name);
+ p->length = special_len;
+ p->value = prom_early_alloc(special_len);
+ memcpy(p->value, special_val, special_len);
+ } else {
+ int fl;
+ if (prev == NULL) {
+ if (ofw("nextprop", 3, 1, node, "", p->name, &fl)) {
+ printk(KERN_ERR "PROM: %s: nextprop failed!\n", __func__);
+ return NULL;
+ }
+ } else {
+ if (ofw("nextprop", 3, 1, node, prev, p->name, &fl)) {
+ printk(KERN_ERR "PROM: %s: nextprop failed!\n", __func__);
+ return NULL;
+ }
+ }
+ if (strlen(p->name) == 0 || fl != 1) {
+ tmp = p;
+ return NULL;
+ }
+ if (ofw("getproplen", 2, 1, node, p->name, &p->length)) {
+ printk(KERN_ERR "PROM: %s: getproplen failed!\n", __func__);
+ return NULL;
+ }
+ if (p->length <= 0) {
+ p->length = 0;
+ } else {
+ p->value = prom_early_alloc(p->length + 1);
+ if (ofw("getprop", 4, 1, node, p->name, p->value, p->length, &p->length)) {
+ printk(KERN_ERR "PROM: %s: getprop failed!\n", __func__);
+ return NULL;
+ }
+ ((unsigned char *)p->value)[p->length] = '\0';
+ }
+ }
+ return p;
+}
+
+static struct property * __init build_prop_list(phandle node)
+{
+ struct property *head, *tail;
+
+ head = tail = build_one_prop(node, NULL,
+ ".node", &node, sizeof(node));
+
+ tail->next = build_one_prop(node, NULL, NULL, NULL, 0);
+ tail = tail->next;
+ while(tail) {
+ tail->next = build_one_prop(node, tail->name,
+ NULL, NULL, 0);
+ tail = tail->next;
+ }
+
+ return head;
+}
+
+static char * __init get_one_property(phandle node, const char *name)
+{
+ char *buf = "<NULL>";
+ int len;
+
+ if (ofw("getproplen", 2, 1, node, name, &len)) {
+ printk(KERN_ERR "PROM: %s: getproplen failed!\n", __func__);
+ return NULL;
+ }
+ if (len > 0) {
+ buf = prom_early_alloc(len);
+ if (ofw("getprop", 4, 1, node, name, buf, len, &len)) {
+ printk(KERN_ERR "PROM: %s: getprop failed!\n", __func__);
+ return NULL;
+ }
+ }
+
+ return buf;
+}
+
+static struct device_node * __init create_node(phandle node, struct device_node *parent)
+{
+ struct device_node *dp;
+
+ if (!node)
+ return NULL;
+
+ dp = prom_early_alloc(sizeof(*dp));
+ dp->parent = parent;
+
+ kref_init(&dp->kref);
+
+ dp->name = get_one_property(node, "name");
+ dp->type = get_one_property(node, "device_type");
+ dp->node = node;
+
+ dp->properties = build_prop_list(node);
+
+ return dp;
+}
+
+static struct device_node * __init build_tree(struct device_node *parent, phandle node, struct device_node ***nextp)
+{
+ struct device_node *ret = NULL, *prev_sibling = NULL;
+ struct device_node *dp;
+ u32 child;
+
+ while (1) {
+ dp = create_node(node, parent);
+ if (!dp)
+ break;
+
+ if (prev_sibling)
+ prev_sibling->sibling = dp;
+
+ if (!ret)
+ ret = dp;
+ prev_sibling = dp;
+
+ *(*nextp) = dp;
+ *nextp = &dp->allnext;
+
+ dp->path_component_name = build_path_component(dp);
+ dp->full_name = build_full_name(dp);
+
+ if (ofw("child", 1, 1, node, &child)) {
+ printk(KERN_ERR "PROM: %s: fetching child failed!\n", __func__);
+ return NULL;
+ }
+ dp->child = build_tree(dp, child, nextp);
+
+ if (ofw("peer", 1, 1, node, &node)) {
+ printk(KERN_ERR "PROM: %s: fetching peer failed!\n", __func__);
+ return NULL;
+ }
+ }
+
+ return ret;
+}
+
+static phandle root_node;
+
+void __init prom_build_devicetree(void)
+{
+ struct device_node **nextp;
+ u32 child;
+
+ if (ofw("peer", 1, 1, 0, &root_node)) {
+ printk(KERN_ERR "PROM: unable to get root node from OFW!\n");
+ return;
+ }
+
+ allnodes = create_node(root_node, NULL);
+ allnodes->path_component_name = "";
+ allnodes->full_name = "/";
+
+ nextp = &allnodes->allnext;
+ if (ofw("child", 1, 1, allnodes->node, &child)) {
+ printk(KERN_ERR "PROM: unable to get child node from OFW!\n");
+ return;
+ }
+ allnodes->child = build_tree(allnodes, child, &nextp);
+ printk("PROM: Built device tree with %u bytes of memory.\n",
+ prom_early_allocated);
+}
projects / openwrt.git / blobdiff