/*
* Copyright (c) 2006 Jakub Jermar
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/** @addtogroup ofw
* @{
*/
/**
* @file
* @brief OpenFirmware device tree navigation.
*
*/
#include <genarch/ofw/ofw_tree.h>
#include <arch/memstr.h>
#include <mm/slab.h>
#include <func.h>
#include <print.h>
#include <panic.h>
#define PATH_MAX_LEN 80
#define NAME_BUF_LEN 50
static ofw_tree_node_t *ofw_root;
void ofw_tree_init(ofw_tree_node_t *root)
{
ofw_root = root;
}
/** Get OpenFirmware node property.
*
* @param node Node in which to lookup the property.
* @param name Name of the property.
*
* @return Pointer to the property structure or NULL if no such property.
*/
ofw_tree_property_t *ofw_tree_getprop(const ofw_tree_node_t *node, const char *name)
{
int i;
for (i = 0; i < node->properties; i++) {
if (strcmp(node
->property
[i
].
name, name
) == 0) return &node->property[i];
}
return NULL;
}
/** Return value of the 'name' property.
*
* @param node Node of interest.
*
* @return Value of the 'name' property belonging to the node.
*/
const char *ofw_tree_node_name(const ofw_tree_node_t *node)
{
ofw_tree_property_t *prop;
prop = ofw_tree_getprop(node, "name");
if (!prop)
panic("Node without name property.\n");
if (prop->size < 2)
panic("Invalid name property.\n");
return prop->value;
}
/** Lookup child of given name.
*
* @param node Node whose child is being looked up.
* @param name Name of the child being looked up.
*
* @return NULL if there is no such child or pointer to the matching child node.
*/
ofw_tree_node_t *ofw_tree_find_child(ofw_tree_node_t *node, const char *name)
{
ofw_tree_node_t *cur;
/*
* Try to find the disambigued name.
*/
for (cur = node->child; cur; cur = cur->peer) {
if (strcmp(cur
->da_name
, name
) == 0) return cur;
}
/*
* Disambigued name not found.
* Lets try our luck with possibly ambiguous "name" property.
*
* We need to do this because paths stored in "/aliases"
* are not always fully-qualified.
*/
for (cur = node->child; cur; cur = cur->peer) {
if (strcmp(ofw_tree_node_name
(cur
), name
) == 0) return cur;
}
return NULL;
}
/** Lookup first child of given device type.
*
* @param node Node whose child is being looked up.
* @param name Device type of the child being looked up.
*
* @return NULL if there is no such child or pointer to the matching child node.
*/
ofw_tree_node_t *ofw_tree_find_child_by_device_type(ofw_tree_node_t *node, const char *name)
{
ofw_tree_node_t *cur;
ofw_tree_property_t *prop;
for (cur = node->child; cur; cur = cur->peer) {
prop = ofw_tree_getprop(cur, "device_type");
if (!prop || !prop->value)
continue;
if (strcmp(prop
->value
, name
) == 0) return cur;
}
return NULL;
}
/** Lookup node with matching node_handle.
*
* Child nodes are looked up recursively contrary to peer nodes that
* are looked up iteratively to avoid stack overflow.
*
* @param root Root of the searched subtree.
* @param handle OpenFirmware handle.
*
* @return NULL if there is no such node or pointer to the matching node.
*/
ofw_tree_node_t *ofw_tree_find_node_by_handle(ofw_tree_node_t *root, uint32_t handle)
{
ofw_tree_node_t *cur;
for (cur = root; cur; cur = cur->peer) {
if (cur->node_handle == handle)
return cur;
if (cur->child) {
ofw_tree_node_t *node;
node = ofw_tree_find_node_by_handle(cur->child, handle);
if (node)
return node;
}
}
return NULL;
}
/** Lookup first peer of given device type.
*
* @param node Node whose peer is being looked up.
* @param name Device type of the child being looked up.
*
* @return NULL if there is no such child or pointer to the matching child node.
*/
ofw_tree_node_t *ofw_tree_find_peer_by_device_type(ofw_tree_node_t *node, const char *name)
{
ofw_tree_node_t *cur;
ofw_tree_property_t *prop;
for (cur = node->peer; cur; cur = cur->peer) {
prop = ofw_tree_getprop(cur, "device_type");
if (!prop || !prop->value)
continue;
if (strcmp(prop
->value
, name
) == 0) return cur;
}
return NULL;
}
/** Lookup OpenFirmware node by its path.
*
* @param path Path to the node.
*
* @return NULL if there is no such node or pointer to the leaf node.
*/
ofw_tree_node_t *ofw_tree_lookup(const char *path)
{
char buf[NAME_BUF_LEN+1];
ofw_tree_node_t *node = ofw_root;
index_t i, j;
if (path[0] != '/')
return NULL;
for (i
= 1; i
< strlen(path
) && node
; i
= j
+ 1) { for (j
= i
; j
< strlen(path
) && path
[j
] != '/'; j
++) ;
if (i == j) /* skip extra slashes */
continue;
buf[j - i] = '\0';
node = ofw_tree_find_child(node, buf);
}
return node;
}
/** Print OpenFirmware device subtree rooted in a node.
*
* Child nodes are processed recursively and peer nodes are processed
* iteratively in order to avoid stack overflow.
*
* @param node Root of the subtree.
* @param path Current path, NULL for the very root of the entire tree.
*/
static void ofw_tree_node_print(const ofw_tree_node_t *node, const char *path)
{
char *p;
const ofw_tree_node_t *cur;
p
= (char *) malloc(PATH_MAX_LEN
, 0);
for (cur = node; cur; cur = cur->peer) {
if (cur->parent) {
snprintf(p
, PATH_MAX_LEN
, "%s/%s", path
, cur
->da_name
); } else {
snprintf(p
, PATH_MAX_LEN
, "%s", cur
->da_name
); }
if (cur->child)
ofw_tree_node_print(cur->child, p);
}
}
/** Print the structure of the OpenFirmware device tree. */
void ofw_tree_print(void)
{
ofw_tree_node_print(ofw_root, NULL);
}
/** @}
*/