blob: 3416e6c4b69a2b917b0a8d65fa562293a19566df [file] [log] [blame]
/*
* Copyright 2013 Google Inc.
*
* See file CREDITS for list of people who contributed to this
* project.
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but without any warranty; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <assert.h>
#include <endian.h>
#include <libpayload.h>
#include <stdint.h>
#include "base/device_tree.h"
/*
* Functions for picking apart flattened trees.
*/
static uint32_t size32(uint32_t val)
{
return (val + sizeof(uint32_t) - 1) / sizeof(uint32_t);
}
int fdt_next_property(void *blob, uint32_t offset, FdtProperty *prop)
{
FdtHeader *header = (FdtHeader *)blob;
uint32_t *ptr = (uint32_t *)(((uint8_t *)blob) + offset);
int index = 0;
if (betohl(ptr[index++]) != TokenProperty)
return 0;
uint32_t size = betohl(ptr[index++]);
uint32_t name_offset = betohl(ptr[index++]);
name_offset += betohl(header->strings_offset);
if (prop) {
prop->name = (char *)((uint8_t *)blob + name_offset);
prop->data = &ptr[index];
prop->size = size;
}
index += size32(size);
return index * 4;
}
int fdt_node_name(void *blob, uint32_t offset, const char **name)
{
uint8_t *ptr = ((uint8_t *)blob) + offset;
if (betohl(*(uint32_t *)ptr) != TokenBeginNode)
return 0;
ptr += 4;
if (name)
*name = (char *)ptr;
return size32(strlen((char *)ptr) + 1) * sizeof(uint32_t) + 4;
}
/*
* Functions for printing flattened trees.
*/
static void print_indent(int depth)
{
while (depth--)
printf(" ");
}
static void print_property(FdtProperty *prop, int depth)
{
print_indent(depth);
printf("prop \"%s\" (%d bytes).\n", prop->name, prop->size);
print_indent(depth + 1);
for (int i = 0; i < MIN(25, prop->size); i++) {
printf("%02x ", ((uint8_t *)prop->data)[i]);
}
if (prop->size > 25)
printf("...");
printf("\n");
}
static int print_flat_node(void *blob, uint32_t start_offset, int depth)
{
int offset = start_offset;
const char *name;
int size;
size = fdt_node_name(blob, offset, &name);
if (!size)
return 0;
offset += size;
print_indent(depth);
printf("name = %s\n", name);
FdtProperty prop;
while ((size = fdt_next_property(blob, offset, &prop))) {
print_property(&prop, depth + 1);
offset += size;
}
while ((size = print_flat_node(blob, offset, depth + 1)))
offset += size;
return offset - start_offset + sizeof(uint32_t);
}
void fdt_print_node(void *blob, uint32_t offset)
{
print_flat_node(blob, offset, 0);
}
/*
* A utility function to skip past nodes in flattened trees.
*/
int fdt_skip_node(void *blob, uint32_t start_offset)
{
int offset = start_offset;
int size;
const char *name;
size = fdt_node_name(blob, offset, &name);
if (!size)
return 0;
offset += size;
while ((size = fdt_next_property(blob, offset, NULL)))
offset += size;
while ((size = fdt_skip_node(blob, offset)))
offset += size;
return offset - start_offset + sizeof(uint32_t);
}
/*
* Functions to turn a flattened tree into an unflattened one.
*/
static DeviceTreeNode node_cache[1000];
static int node_counter = 0;
static DeviceTreeProperty prop_cache[5000];
static int prop_counter = 0;
/*
* Libpayload's malloc() has linear allocation complexity and goes completely
* mental after a few thousand small requests. This little hack will absorb
* the worst of it to avoid increasing boot time for no reason.
*/
static DeviceTreeNode *alloc_node(void)
{
if (node_counter >= ARRAY_SIZE(node_cache))
return xzalloc(sizeof(DeviceTreeNode));
return &node_cache[node_counter++];
}
static DeviceTreeProperty *alloc_prop(void)
{
if (prop_counter >= ARRAY_SIZE(prop_cache))
return xzalloc(sizeof(DeviceTreeProperty));
return &prop_cache[prop_counter++];
}
static int fdt_unflatten_node(void *blob, uint32_t start_offset,
DeviceTreeNode **new_node)
{
ListNode *last;
int offset = start_offset;
const char *name;
int size;
size = fdt_node_name(blob, offset, &name);
if (!size)
return 0;
offset += size;
DeviceTreeNode *node = alloc_node();
*new_node = node;
node->name = name;
FdtProperty fprop;
last = &node->properties;
while ((size = fdt_next_property(blob, offset, &fprop))) {
DeviceTreeProperty *prop = alloc_prop();
prop->prop = fprop;
list_insert_after(&prop->list_node, last);
last = &prop->list_node;
offset += size;
}
DeviceTreeNode *child;
last = &node->children;
while ((size = fdt_unflatten_node(blob, offset, &child))) {
list_insert_after(&child->list_node, last);
last = &child->list_node;
offset += size;
}
return offset - start_offset + sizeof(uint32_t);
}
static int fdt_unflatten_map_entry(void *blob, uint32_t offset,
DeviceTreeReserveMapEntry **new_entry)
{
uint64_t *ptr = (uint64_t *)(((uint8_t *)blob) + offset);
uint64_t start = betohll(ptr[0]);
uint64_t size = betohll(ptr[1]);
if (!size)
return 0;
DeviceTreeReserveMapEntry *entry = xzalloc(sizeof(*entry));
*new_entry = entry;
entry->start = start;
entry->size = size;
return sizeof(uint64_t) * 2;
}
DeviceTree *fdt_unflatten(void *blob)
{
DeviceTree *tree = xzalloc(sizeof(*tree));
FdtHeader *header = (FdtHeader *)blob;
tree->header = header;
uint32_t struct_offset = betohl(header->structure_offset);
uint32_t strings_offset = betohl(header->strings_offset);
uint32_t reserve_offset = betohl(header->reserve_map_offset);
uint32_t min_offset = 0;
min_offset = MIN(struct_offset, strings_offset);
min_offset = MIN(min_offset, reserve_offset);
// Assume everything up to the first non-header component is part of
// the header and needs to be preserved. This will protect us against
// new elements being added in the future.
tree->header_size = min_offset;
DeviceTreeReserveMapEntry *entry;
uint32_t offset = reserve_offset;
int size;
ListNode *last = &tree->reserve_map;
while ((size = fdt_unflatten_map_entry(blob, offset, &entry))) {
list_insert_after(&entry->list_node, last);
last = &entry->list_node;
offset += size;
}
fdt_unflatten_node(blob, struct_offset, &tree->root);
return tree;
}
/*
* Functions to find the size of device tree would take if it was flattened.
*/
static void dt_flat_prop_size(DeviceTreeProperty *prop, uint32_t *struct_size,
uint32_t *strings_size)
{
// Starting token.
*struct_size += sizeof(uint32_t);
// Size.
*struct_size += sizeof(uint32_t);
// Name offset.
*struct_size += sizeof(uint32_t);
// Property value.
*struct_size += size32(prop->prop.size) * sizeof(uint32_t);
// Property name.
*strings_size += strlen(prop->prop.name) + 1;
}
static void dt_flat_node_size(DeviceTreeNode *node, uint32_t *struct_size,
uint32_t *strings_size)
{
// Starting token.
*struct_size += sizeof(uint32_t);
// Node name.
*struct_size += size32(strlen(node->name) + 1) * sizeof(uint32_t);
DeviceTreeProperty *prop;
list_for_each(prop, node->properties, list_node)
dt_flat_prop_size(prop, struct_size, strings_size);
DeviceTreeNode *child;
list_for_each(child, node->children, list_node)
dt_flat_node_size(child, struct_size, strings_size);
// End token.
*struct_size += sizeof(uint32_t);
}
uint32_t dt_flat_size(DeviceTree *tree)
{
uint32_t size = tree->header_size;
DeviceTreeReserveMapEntry *entry;
list_for_each(entry, tree->reserve_map, list_node)
size += sizeof(uint64_t) * 2;
size += sizeof(uint64_t) * 2;
uint32_t struct_size = 0;
uint32_t strings_size = 0;
dt_flat_node_size(tree->root, &struct_size, &strings_size);
size += struct_size;
// End token.
size += sizeof(uint32_t);
size += strings_size;
return size;
}
/*
* Functions to flatten a device tree.
*/
static void dt_flatten_map_entry(DeviceTreeReserveMapEntry *entry,
void **map_start)
{
((uint64_t *)*map_start)[0] = htobell(entry->start);
((uint64_t *)*map_start)[1] = htobell(entry->size);
*map_start = ((uint8_t *)*map_start) + sizeof(uint64_t) * 2;
}
static void dt_flatten_prop(DeviceTreeProperty *prop, void **struct_start,
void *strings_base, void **strings_start)
{
uint8_t *dstruct = (uint8_t *)*struct_start;
uint8_t *dstrings = (uint8_t *)*strings_start;
*((uint32_t *)dstruct) = htobel(TokenProperty);
dstruct += sizeof(uint32_t);
*((uint32_t *)dstruct) = htobel(prop->prop.size);
dstruct += sizeof(uint32_t);
uint32_t name_offset = (uintptr_t)dstrings - (uintptr_t)strings_base;
*((uint32_t *)dstruct) = htobel(name_offset);
dstruct += sizeof(uint32_t);
strcpy((char *)dstrings, prop->prop.name);
dstrings += strlen(prop->prop.name) + 1;
memcpy(dstruct, prop->prop.data, prop->prop.size);
dstruct += size32(prop->prop.size) * 4;
*struct_start = dstruct;
*strings_start = dstrings;
}
static void dt_flatten_node(DeviceTreeNode *node, void **struct_start,
void *strings_base, void **strings_start)
{
uint8_t *dstruct = (uint8_t *)*struct_start;
uint8_t *dstrings = (uint8_t *)*strings_start;
*((uint32_t *)dstruct) = htobel(TokenBeginNode);
dstruct += sizeof(uint32_t);
strcpy((char *)dstruct, node->name);
dstruct += size32(strlen(node->name) + 1) * 4;
DeviceTreeProperty *prop;
list_for_each(prop, node->properties, list_node)
dt_flatten_prop(prop, (void **)&dstruct, strings_base,
(void **)&dstrings);
DeviceTreeNode *child;
list_for_each(child, node->children, list_node)
dt_flatten_node(child, (void **)&dstruct, strings_base,
(void **)&dstrings);
*((uint32_t *)dstruct) = htobel(TokenEndNode);
dstruct += sizeof(uint32_t);
*struct_start = dstruct;
*strings_start = dstrings;
}
void dt_flatten(DeviceTree *tree, void *start_dest)
{
uint8_t *dest = (uint8_t *)start_dest;
memcpy(dest, tree->header, tree->header_size);
FdtHeader *header = (FdtHeader *)dest;
dest += tree->header_size;
DeviceTreeReserveMapEntry *entry;
list_for_each(entry, tree->reserve_map, list_node)
dt_flatten_map_entry(entry, (void **)&dest);
((uint64_t *)dest)[0] = ((uint64_t *)dest)[1] = 0;
dest += sizeof(uint64_t) * 2;
uint32_t struct_size = 0;
uint32_t strings_size = 0;
dt_flat_node_size(tree->root, &struct_size, &strings_size);
uint8_t *struct_start = dest;
header->structure_offset = htobel(dest - (uint8_t *)start_dest);
header->structure_size = htobel(struct_size);
dest += struct_size;
*((uint32_t *)dest) = htobel(TokenEnd);
dest += sizeof(uint32_t);
uint8_t *strings_start = dest;
header->strings_offset = htobel(dest - (uint8_t *)start_dest);
header->strings_size = htobel(strings_size);
dest += strings_size;
dt_flatten_node(tree->root, (void **)&struct_start, strings_start,
(void **)&strings_start);
header->totalsize = htobel(dest - (uint8_t *)start_dest);
}
/*
* Functions for printing a non-flattened device tree.
*/
static void print_node(DeviceTreeNode *node, int depth)
{
print_indent(depth);
printf("name = %s\n", node->name);
DeviceTreeProperty *prop;
list_for_each(prop, node->properties, list_node)
print_property(&prop->prop, depth + 1);
DeviceTreeNode *child;
list_for_each(child, node->children, list_node)
print_node(child, depth + 1);
}
void dt_print_node(DeviceTreeNode *node)
{
print_node(node, 0);
}
/*
* Functions for reading and manipulating an unflattened device tree.
*/
/*
* Read #address-cells and #size-cells properties from a node.
*
* @param node The device tree node to read from.
* @param addrcp Pointer to store #address-cells in, skipped if NULL.
* @param sizecp Pointer to store #size-cells in, skipped if NULL.
*/
void dt_read_cell_props(DeviceTreeNode *node, u32 *addrcp, u32 *sizecp)
{
DeviceTreeProperty *prop;
list_for_each(prop, node->properties, list_node) {
if (addrcp && !strcmp("#address-cells", prop->prop.name))
*addrcp = betohl(*(u32 *)prop->prop.data);
if (sizecp && !strcmp("#size-cells", prop->prop.name))
*sizecp = betohl(*(u32 *)prop->prop.data);
}
}
/*
* Find a node from a device tree path, relative to a parent node.
*
* @param parent The node from which to start the relative path lookup.
* @param path An array of path component strings that will be looked
* up in order to find the node. Must be terminated with
* a NULL pointer. Example: {'firmware', 'coreboot', NULL}
* @param addrcp Pointer that will be updated with any #address-cells
* value found in the path. May be NULL to ignore.
* @param sizecp Pointer that will be updated with any #size-cells
* value found in the path. May be NULL to ignore.
* @param create 1: Create node(s) if not found. 0: Return NULL instead.
* @return The found/created node, or NULL.
*/
DeviceTreeNode *dt_find_node(DeviceTreeNode *parent, const char **path,
u32 *addrcp, u32 *sizecp, int create)
{
DeviceTreeNode *node, *found = NULL;
// Update #address-cells and #size-cells for this level.
dt_read_cell_props(parent, addrcp, sizecp);
if (!*path)
return parent;
// Find the next node in the path, if it exists.
list_for_each(node, parent->children, list_node) {
if (!strcmp(node->name, *path)) {
found = node;
break;
}
}
// Otherwise create it or return NULL.
if (!found) {
if (!create)
return NULL;
/*
* This data structure will be flattened (= deep copy) before
* it is passed to the kernel. Therefore, we can just store a
* pointer to the interned string from 'path' here, even though
* it lives in depthcharge's .rodata section.
*/
found = alloc_node();
found->name = *path;
list_insert_after(&found->list_node, &parent->children);
}
return dt_find_node(found, path + 1, addrcp, sizecp, create);
}
/*
* Find a node from a compatible string, in the subtree of a parent node.
*
* @param parent The parent node under which to look.
* @param compat The compatible string to find.
* @return The found node, or NULL.
*/
DeviceTreeNode *dt_find_compat(DeviceTreeNode *parent, const char *compat)
{
DeviceTreeProperty *prop;
// Check if the parent node itself is compatible.
list_for_each(prop, parent->properties, list_node) {
if (!strcmp("compatible", prop->prop.name)) {
int bytes = prop->prop.size;
const char *str = prop->prop.data;
while (bytes > 0) {
if (!strncmp(compat, str, bytes))
return parent;
int len = strnlen(str, bytes) + 1;
str += len;
bytes -= len;
}
break;
}
}
DeviceTreeNode *child;
list_for_each(child, parent->children, list_node) {
DeviceTreeNode *found = dt_find_compat(child, compat);
if (found)
return found;
}
return NULL;
}
/*
* Write an arbitrary sized big-endian integer into a pointer.
*
* @param dest Pointer to the DT property data buffer to write.
* @param src The integer to write (in CPU endianess).
* @param length the length of the destination integer in bytes.
*/
void dt_write_int(u8 *dest, u64 src, size_t length)
{
while (length--) {
dest[length] = (u8)src;
src >>= 8;
}
}
/*
* Add an arbitrary property to a node, or update it if it already exists.
*
* @param node The device tree node to add to.
* @param name The name of the new property.
* @param data The raw data blob to be stored in the property.
* @param size The size of data in bytes.
*/
void dt_add_bin_prop(DeviceTreeNode *node, char *name, void *data, size_t size)
{
DeviceTreeProperty *prop;
list_for_each(prop, node->properties, list_node) {
if (!strcmp(prop->prop.name, name)) {
prop->prop.data = data;
prop->prop.size = size;
return;
}
}
prop = alloc_prop();
list_insert_after(&prop->list_node, &node->properties);
prop->prop.name = name;
prop->prop.data = data;
prop->prop.size = size;
}
/*
* Add a string property to a node, or update it if it already exists.
*
* @param node The device tree node to add to.
* @param name The name of the new property.
* @param str The zero-terminated string to be stored in the property.
*/
void dt_add_string_prop(DeviceTreeNode *node, char *name, char *str)
{
dt_add_bin_prop(node, name, str, strlen(str) + 1);
}
/*
* Add a 32-bit integer property to a node, or update it if it already exists.
*
* @param node The device tree node to add to.
* @param name The name of the new property.
* @param val The integer to be stored in the property.
*/
void dt_add_u32_prop(DeviceTreeNode *node, char *name, u32 val)
{
u32 *val_ptr = xmalloc(sizeof(val));
*val_ptr = htobel(val);
dt_add_bin_prop(node, name, val_ptr, sizeof(*val_ptr));
}
/*
* Add a 'reg' address list property to a node, or update it if it exists.
*
* @param node The device tree node to add to.
* @param addrs Array of address values to be stored in the property.
* @param sizes Array of corresponding size values to 'addrs'.
* @param count Number of values in 'addrs' and 'sizes' (must be equal).
* @param addr_cells Value of #address-cells property valid for this node.
* @param size_cells Value of #size-cells property valid for this node.
*/
void dt_add_reg_prop(DeviceTreeNode *node, u64 *addrs, u64 *sizes,
int count, u32 addr_cells, u32 size_cells)
{
int i;
size_t length = (addr_cells + size_cells) * sizeof(u32) * count;
u8 *data = xmalloc(length);
u8 *cur = data;
for (i = 0; i < count; i++) {
dt_write_int(cur, addrs[i], addr_cells * sizeof(u32));
cur += addr_cells * sizeof(u32);
dt_write_int(cur, sizes[i], size_cells * sizeof(u32));
cur += size_cells * sizeof(u32);
}
dt_add_bin_prop(node, "reg", data, length);
}
/*
* Fixups to apply to a kernel's device tree before booting it.
*/
ListNode device_tree_fixups;
int dt_apply_fixups(DeviceTree *tree)
{
DeviceTreeFixup *fixup;
list_for_each(fixup, device_tree_fixups, list_node) {
assert(fixup->fixup);
if (fixup->fixup(fixup, tree))
return 1;
}
return 0;
}