| /* |
| * 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 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 = xzalloc(sizeof(*node)); |
| *new_node = node; |
| node->name = name; |
| |
| FdtProperty fprop; |
| last = &node->properties; |
| while ((size = fdt_next_property(blob, offset, &fprop))) { |
| DeviceTreeProperty *prop = xzalloc(sizeof(*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); |
| } |
| |
| |
| |
| /* |
| * Utility function for finding #address-cells and #size-cells properties |
| * in a node. |
| */ |
| |
| void dt_node_cell_props(DeviceTreeNode *node, unsigned *addr, unsigned *size) |
| { |
| DeviceTreeProperty *prop; |
| list_for_each(prop, node->properties, list_node) { |
| if (!strcmp("#address-cells", prop->prop.name)) |
| *addr = betohl(*(uint32_t *)prop->prop.data); |
| if (!strcmp("#size-cells", prop->prop.name)) |
| *size = betohl(*(uint32_t *)prop->prop.data); |
| } |
| } |
| |
| |
| |
| /* |
| * 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; |
| } |