/*
* 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.
*/
#include <genarch/ofw_tree.h>
#include <genarch/ofw.h>
#include <arch/ofw.h>
#include <stddef.h>
#include <str.h>
#include <balloc.h>
#include <mem.h>
static char path[OFW_TREE_PATH_MAX_LEN + 1];
static char name[OFW_TREE_PROPERTY_MAX_NAMELEN];
static char name2[OFW_TREE_PROPERTY_MAX_NAMELEN];
static ofw_tree_node_t *ofw_tree_node_alloc(void)
{
return balloc(sizeof(ofw_tree_node_t), sizeof(ofw_tree_node_t));
}
static ofw_tree_property_t *ofw_tree_properties_alloc(size_t count)
{
return balloc(count * sizeof(ofw_tree_property_t),
sizeof(ofw_tree_property_t));
}
static void *ofw_tree_space_alloc(size_t size)
{
/*
* What we do here is a nasty hack :-)
* Problem: string property values that are allocated via this
* function typically do not contain the trailing '\0'. This
* is very uncomfortable for kernel, which is supposed to deal
* with the properties.
* Solution: when allocating space via this function, we always
* allocate space for the extra '\0' character that we store
* behind the requested memory.
*/
char *addr = balloc(size + 1, 4);
if (addr)
addr[size] = '\0';
return addr;
}
/** Transfer information from one OpenFirmware node into its memory
* representation.
*
* Transfer entire information from the OpenFirmware device tree 'current' node
* to its memory representation in 'current_node'. This function recursively
* processes all node's children. Node's peers are processed iteratively in
* order to prevent stack from overflowing.
*
* @param current_node Pointer to uninitialized ofw_tree_node structure that
* will become the memory represenation of 'current'.
* @param parent_node Parent ofw_tree_node structure or NULL in case of root
* node.
* @param current OpenFirmware phandle to the current device tree node.
*
*/
static void ofw_tree_node_process(ofw_tree_node_t *current_node,
ofw_tree_node_t *parent_node, phandle current)
{
while (current_node) {
/*
* Initialize node.
*/
current_node->parent = (ofw_tree_node_t *) balloc_rebase(parent_node);
current_node->peer = NULL;
current_node->child = NULL;
current_node->node_handle = current;
current_node->properties = 0;
current_node->property = NULL;
current_node->device = NULL;
/*
* Get the disambigued name.
*/
size_t len = ofw_package_to_path(current, path, OFW_TREE_PATH_MAX_LEN);
if (len == (size_t) -1)
return;
path[len] = '\0';
/* Find last slash */
size_t i;
i = len;
while (i > 0 && path[i - 1] != '/')
i--;
/* Do not include the slash */
len -= i;
/* Add space for trailing '\0' */
char *da_name = ofw_tree_space_alloc(len + 1);
if (!da_name)
return;
memcpy(da_name, &path[i], len);
da_name[len] = '\0';
current_node->da_name = (char *) balloc_rebase(da_name);
/*
* Recursively process the potential child node.
*/
phandle child = ofw_get_child_node(current);
if ((child != 0) && (child != (phandle) -1)) {
ofw_tree_node_t *child_node = ofw_tree_node_alloc();
if (child_node) {
ofw_tree_node_process(child_node, current_node,
child);
current_node->child =
(ofw_tree_node_t *) balloc_rebase(child_node);
}
}
/*
* Count properties.
*/
name[0] = '\0';
while (ofw_next_property(current, name, name2) == 1) {
current_node->properties++;
memcpy(name, name2, OFW_TREE_PROPERTY_MAX_NAMELEN);
}
if (!current_node->properties)
return;
/*
* Copy properties.
*/
ofw_tree_property_t *property =
ofw_tree_properties_alloc(current_node->properties);
if (!property)
return;
name[0] = '\0';
for (i = 0; ofw_next_property(current, name, name2) == 1; i++) {
if (i == current_node->properties)
break;
memcpy(name, name2, OFW_TREE_PROPERTY_MAX_NAMELEN);
memcpy(property[i].name, name, OFW_TREE_PROPERTY_MAX_NAMELEN);
property[i].name[OFW_TREE_PROPERTY_MAX_NAMELEN - 1] = '\0';
size_t size = ofw_get_proplen(current, name);
property[i].size = size;
if (size) {
void *buf = ofw_tree_space_alloc(size);
if (buf) {
/*
* Copy property value to memory node.
*/
(void) ofw_get_property(current, name, buf, size);
property[i].value = balloc_rebase(buf);
}
} else
property[i].value = NULL;
}
/* Just in case we ran out of memory. */
current_node->properties = i;
current_node->property = (ofw_tree_property_t *) balloc_rebase(property);
/*
* Iteratively process the next peer node.
* Note that recursion is a bad idea here.
* Due to the topology of the OpenFirmware device tree,
* the nesting of peer nodes could be to wide and the
* risk of overflowing the stack is too real.
*/
phandle peer = ofw_get_peer_node(current);
if ((peer != 0) && (peer != (phandle) -1)) {
ofw_tree_node_t *peer_node = ofw_tree_node_alloc();
if (peer_node) {
current_node->peer = (ofw_tree_node_t *) balloc_rebase(peer_node);
current_node = peer_node;
current = peer;
/*
* Process the peer in next iteration.
*/
continue;
}
}
/*
* No more peers on this level.
*/
break;
}
}
/** Construct memory representation of OpenFirmware device tree.
*
* @return NULL on failure or kernel pointer to the root node.
*
*/
ofw_tree_node_t *ofw_tree_build(void)
{
ofw_tree_node_t *root = ofw_tree_node_alloc();
if (root)
ofw_tree_node_process(root, NULL, ofw_root);
/*
* The firmware client interface does not automatically include the
* "ssm" node in the list of children of "/". A nasty yet working
* solution is to explicitly stick "ssm" to the OFW tree.
*/
phandle ssm_node = ofw_find_device("/ssm@0,0");
if (ssm_node != (phandle) -1) {
ofw_tree_node_t *ssm = ofw_tree_node_alloc();
if (ssm) {
ofw_tree_node_process(ssm, root,
ofw_find_device("/ssm@0,0"));
ssm->peer = root->child;
root->child = (ofw_tree_node_t *) balloc_rebase(ssm);
}
}
return (ofw_tree_node_t *) balloc_rebase(root);
}