qemu/device_tree.c

110 lines
2.6 KiB
C

/*
* Functions to help device tree manipulation using libfdt.
* It also provides functions to read entries from device tree proc
* interface.
*
* Copyright 2008 IBM Corporation.
* Authors: Jerone Young <jyoung5@us.ibm.com>
* Hollis Blanchard <hollisb@us.ibm.com>
*
* This work is licensed under the GNU GPL license version 2 or later.
*
*/
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include "config.h"
#include "qemu-common.h"
#include "sysemu.h"
#include "device_tree.h"
#include <libfdt.h>
void *load_device_tree(const char *filename_path, int *sizep)
{
int dt_size;
int dt_file_load_size;
int ret;
void *fdt = NULL;
*sizep = 0;
dt_size = get_image_size(filename_path);
if (dt_size < 0) {
printf("Unable to get size of device tree file '%s'\n",
filename_path);
goto fail;
}
/* Expand to 2x size to give enough room for manipulation. */
dt_size *= 2;
/* First allocate space in qemu for device tree */
fdt = qemu_mallocz(dt_size);
dt_file_load_size = load_image(filename_path, fdt);
if (dt_file_load_size < 0) {
printf("Unable to open device tree file '%s'\n",
filename_path);
goto fail;
}
ret = fdt_open_into(fdt, fdt, dt_size);
if (ret) {
printf("Unable to copy device tree in memory\n");
goto fail;
}
/* Check sanity of device tree */
if (fdt_check_header(fdt)) {
printf ("Device tree file loaded into memory is invalid: %s\n",
filename_path);
goto fail;
}
*sizep = dt_size;
return fdt;
fail:
qemu_free(fdt);
return NULL;
}
int qemu_devtree_setprop(void *fdt, const char *node_path,
const char *property, uint32_t *val_array, int size)
{
int offset;
offset = fdt_path_offset(fdt, node_path);
if (offset < 0)
return offset;
return fdt_setprop(fdt, offset, property, val_array, size);
}
int qemu_devtree_setprop_cell(void *fdt, const char *node_path,
const char *property, uint32_t val)
{
int offset;
offset = fdt_path_offset(fdt, node_path);
if (offset < 0)
return offset;
return fdt_setprop_cell(fdt, offset, property, val);
}
int qemu_devtree_setprop_string(void *fdt, const char *node_path,
const char *property, const char *string)
{
int offset;
offset = fdt_path_offset(fdt, node_path);
if (offset < 0)
return offset;
return fdt_setprop_string(fdt, offset, property, string);
}