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/*
* 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 "qemu/osdep.h"
#ifdef CONFIG_LINUX
#include <dirent.h>
#endif
#include "qapi/error.h"
#include "qemu-common.h"
#include "qemu/error-report.h"
#include "sysemu/device_tree.h"
#include "sysemu/sysemu.h"
#include "hw/loader.h"
#include "hw/boards.h"
#include "qemu/config-file.h"
#include <libfdt.h>
#define FDT_MAX_SIZE 0x10000
void *create_device_tree(int *sizep)
{
void *fdt;
int ret;
*sizep = FDT_MAX_SIZE;
fdt = g_malloc0(FDT_MAX_SIZE);
ret = fdt_create(fdt, FDT_MAX_SIZE);
if (ret < 0) {
goto fail;
}
ret = fdt_finish_reservemap(fdt);
if (ret < 0) {
goto fail;
}
ret = fdt_begin_node(fdt, "");
if (ret < 0) {
goto fail;
}
ret = fdt_end_node(fdt);
if (ret < 0) {
goto fail;
}
ret = fdt_finish(fdt);
if (ret < 0) {
goto fail;
}
ret = fdt_open_into(fdt, fdt, *sizep);
if (ret) {
error_report("Unable to copy device tree in memory");
exit(1);
}
return fdt;
fail:
error_report("%s Couldn't create dt: %s", __func__, fdt_strerror(ret));
exit(1);
}
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) {
error_report("Unable to get size of device tree file '%s'",
filename_path);
goto fail;
}
/* Expand to 2x size to give enough room for manipulation. */
dt_size += 10000;
dt_size *= 2;
/* First allocate space in qemu for device tree */
fdt = g_malloc0(dt_size);
dt_file_load_size = load_image(filename_path, fdt);
if (dt_file_load_size < 0) {
error_report("Unable to open device tree file '%s'",
filename_path);
goto fail;
}
ret = fdt_open_into(fdt, fdt, dt_size);
if (ret) {
error_report("Unable to copy device tree in memory");
goto fail;
}
/* Check sanity of device tree */
if (fdt_check_header(fdt)) {
error_report("Device tree file loaded into memory is invalid: %s",
filename_path);
goto fail;
}
*sizep = dt_size;
return fdt;
fail:
g_free(fdt);
return NULL;
}
#ifdef CONFIG_LINUX
#define SYSFS_DT_BASEDIR "/proc/device-tree"
/**
* read_fstree: this function is inspired from dtc read_fstree
* @fdt: preallocated fdt blob buffer, to be populated
* @dirname: directory to scan under SYSFS_DT_BASEDIR
* the search is recursive and the tree is searched down to the
* leaves (property files).
*
* the function asserts in case of error
*/
static void read_fstree(void *fdt, const char *dirname)
{
DIR *d;
struct dirent *de;
struct stat st;
const char *root_dir = SYSFS_DT_BASEDIR;
const char *parent_node;
if (strstr(dirname, root_dir) != dirname) {
error_setg(&error_fatal, "%s: %s must be searched within %s",
__func__, dirname, root_dir);
}
parent_node = &dirname[strlen(SYSFS_DT_BASEDIR)];
d = opendir(dirname);
if (!d) {
error_setg(&error_fatal, "%s cannot open %s", __func__, dirname);
}
while ((de = readdir(d)) != NULL) {
char *tmpnam;
if (!g_strcmp0(de->d_name, ".")
|| !g_strcmp0(de->d_name, "..")) {
continue;
}
tmpnam = g_strdup_printf("%s/%s", dirname, de->d_name);
if (lstat(tmpnam, &st) < 0) {
error_setg(&error_fatal, "%s cannot lstat %s", __func__, tmpnam);
}
if (S_ISREG(st.st_mode)) {
gchar *val;
gsize len;
if (!g_file_get_contents(tmpnam, &val, &len, NULL)) {
error_setg(&error_fatal, "%s not able to extract info from %s",
__func__, tmpnam);
}
if (strlen(parent_node) > 0) {
qemu_fdt_setprop(fdt, parent_node,
de->d_name, val, len);
} else {
qemu_fdt_setprop(fdt, "/", de->d_name, val, len);
}
g_free(val);
} else if (S_ISDIR(st.st_mode)) {
char *node_name;
node_name = g_strdup_printf("%s/%s",
parent_node, de->d_name);
qemu_fdt_add_subnode(fdt, node_name);
g_free(node_name);
read_fstree(fdt, tmpnam);
}
g_free(tmpnam);
}
closedir(d);
}
/* load_device_tree_from_sysfs: extract the dt blob from host sysfs */
void *load_device_tree_from_sysfs(void)
{
void *host_fdt;
int host_fdt_size;
host_fdt = create_device_tree(&host_fdt_size);
read_fstree(host_fdt, SYSFS_DT_BASEDIR);
if (fdt_check_header(host_fdt)) {
error_setg(&error_fatal,
"%s host device tree extracted into memory is invalid",
__func__);
}
return host_fdt;
}
#endif /* CONFIG_LINUX */
static int findnode_nofail(void *fdt, const char *node_path)
{
int offset;
offset = fdt_path_offset(fdt, node_path);
if (offset < 0) {
error_report("%s Couldn't find node %s: %s", __func__, node_path,
fdt_strerror(offset));
exit(1);
}
return offset;
}
char **qemu_fdt_node_path(void *fdt, const char *name, char *compat,
Error **errp)
{
int offset, len, ret;
const char *iter_name;
unsigned int path_len = 16, n = 0;
GSList *path_list = NULL, *iter;
char **path_array;
offset = fdt_node_offset_by_compatible(fdt, -1, compat);
while (offset >= 0) {
iter_name = fdt_get_name(fdt, offset, &len);
if (!iter_name) {
offset = len;
break;
}
if (!strcmp(iter_name, name)) {
char *path;
path = g_malloc(path_len);
while ((ret = fdt_get_path(fdt, offset, path, path_len))
== -FDT_ERR_NOSPACE) {
path_len += 16;
path = g_realloc(path, path_len);
}
path_list = g_slist_prepend(path_list, path);
n++;
}
offset = fdt_node_offset_by_compatible(fdt, offset, compat);
}
if (offset < 0 && offset != -FDT_ERR_NOTFOUND) {
error_setg(errp, "%s: abort parsing dt for %s/%s: %s",
__func__, name, compat, fdt_strerror(offset));
for (iter = path_list; iter; iter = iter->next) {
g_free(iter->data);
}
g_slist_free(path_list);
return NULL;
}
path_array = g_new(char *, n + 1);
path_array[n--] = NULL;
for (iter = path_list; iter; iter = iter->next) {
path_array[n--] = iter->data;
}
g_slist_free(path_list);
return path_array;
}
int qemu_fdt_setprop(void *fdt, const char *node_path,
const char *property, const void *val, int size)
{
int r;
r = fdt_setprop(fdt, findnode_nofail(fdt, node_path), property, val, size);
if (r < 0) {
error_report("%s: Couldn't set %s/%s: %s", __func__, node_path,
property, fdt_strerror(r));
exit(1);
}
return r;
}
int qemu_fdt_setprop_cell(void *fdt, const char *node_path,
const char *property, uint32_t val)
{
int r;
r = fdt_setprop_cell(fdt, findnode_nofail(fdt, node_path), property, val);
if (r < 0) {
error_report("%s: Couldn't set %s/%s = %#08x: %s", __func__,
node_path, property, val, fdt_strerror(r));
exit(1);
}
return r;
}
int qemu_fdt_setprop_u64(void *fdt, const char *node_path,
const char *property, uint64_t val)
{
val = cpu_to_be64(val);
return qemu_fdt_setprop(fdt, node_path, property, &val, sizeof(val));
}
int qemu_fdt_setprop_string(void *fdt, const char *node_path,
const char *property, const char *string)
{
int r;
r = fdt_setprop_string(fdt, findnode_nofail(fdt, node_path), property, string);
if (r < 0) {
error_report("%s: Couldn't set %s/%s = %s: %s", __func__,
node_path, property, string, fdt_strerror(r));
exit(1);
}
return r;
}
const void *qemu_fdt_getprop(void *fdt, const char *node_path,
const char *property, int *lenp, Error **errp)
{
int len;
const void *r;
if (!lenp) {
lenp = &len;
}
r = fdt_getprop(fdt, findnode_nofail(fdt, node_path), property, lenp);
if (!r) {
error_setg(errp, "%s: Couldn't get %s/%s: %s", __func__,
node_path, property, fdt_strerror(*lenp));
}
return r;
}
uint32_t qemu_fdt_getprop_cell(void *fdt, const char *node_path,
const char *property, int *lenp, Error **errp)
{
int len;
const uint32_t *p;
if (!lenp) {
lenp = &len;
}
p = qemu_fdt_getprop(fdt, node_path, property, lenp, errp);
if (!p) {
return 0;
} else if (*lenp != 4) {
error_setg(errp, "%s: %s/%s not 4 bytes long (not a cell?)",
__func__, node_path, property);
*lenp = -EINVAL;
return 0;
}
return be32_to_cpu(*p);
}
uint32_t qemu_fdt_get_phandle(void *fdt, const char *path)
{
uint32_t r;
r = fdt_get_phandle(fdt, findnode_nofail(fdt, path));
if (r == 0) {
error_report("%s: Couldn't get phandle for %s: %s", __func__,
path, fdt_strerror(r));
exit(1);
}
return r;
}
int qemu_fdt_setprop_phandle(void *fdt, const char *node_path,
const char *property,
const char *target_node_path)
{
uint32_t phandle = qemu_fdt_get_phandle(fdt, target_node_path);
return qemu_fdt_setprop_cell(fdt, node_path, property, phandle);
}
uint32_t qemu_fdt_alloc_phandle(void *fdt)
{
static int phandle = 0x0;
/*
* We need to find out if the user gave us special instruction at
* which phandle id to start allocating phandles.
*/
if (!phandle) {
phandle = machine_phandle_start(current_machine);
}
if (!phandle) {
/*
* None or invalid phandle given on the command line, so fall back to
* default starting point.
*/
phandle = 0x8000;
}
return phandle++;
}
int qemu_fdt_nop_node(void *fdt, const char *node_path)
{
int r;
r = fdt_nop_node(fdt, findnode_nofail(fdt, node_path));
if (r < 0) {
error_report("%s: Couldn't nop node %s: %s", __func__, node_path,
fdt_strerror(r));
exit(1);
}
return r;
}
int qemu_fdt_add_subnode(void *fdt, const char *name)
{
char *dupname = g_strdup(name);
char *basename = strrchr(dupname, '/');
int retval;
int parent = 0;
if (!basename) {
g_free(dupname);
return -1;
}
basename[0] = '\0';
basename++;
if (dupname[0]) {
parent = findnode_nofail(fdt, dupname);
}
retval = fdt_add_subnode(fdt, parent, basename);
if (retval < 0) {
error_report("FDT: Failed to create subnode %s: %s", name,
fdt_strerror(retval));
exit(1);
}
g_free(dupname);
return retval;
}
void qemu_fdt_dumpdtb(void *fdt, int size)
{
const char *dumpdtb = qemu_opt_get(qemu_get_machine_opts(), "dumpdtb");
if (dumpdtb) {
/* Dump the dtb to a file and quit */
exit(g_file_set_contents(dumpdtb, fdt, size, NULL) ? 0 : 1);
}
}
int qemu_fdt_setprop_sized_cells_from_array(void *fdt,
const char *node_path,
const char *property,
int numvalues,
uint64_t *values)
{
uint32_t *propcells;
uint64_t value;
int cellnum, vnum, ncells;
uint32_t hival;
int ret;
propcells = g_new0(uint32_t, numvalues * 2);
cellnum = 0;
for (vnum = 0; vnum < numvalues; vnum++) {
ncells = values[vnum * 2];
if (ncells != 1 && ncells != 2) {
ret = -1;
goto out;
}
value = values[vnum * 2 + 1];
hival = cpu_to_be32(value >> 32);
if (ncells > 1) {
propcells[cellnum++] = hival;
} else if (hival != 0) {
ret = -1;
goto out;
}
propcells[cellnum++] = cpu_to_be32(value);
}
ret = qemu_fdt_setprop(fdt, node_path, property, propcells,
cellnum * sizeof(uint32_t));
out:
g_free(propcells);
return ret;
}
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