diff options
Diffstat (limited to 'device_tree.c')
| -rw-r--r-- | device_tree.c | 190 |
1 files changed, 174 insertions, 16 deletions
diff --git a/device_tree.c b/device_tree.c index a9f5f8e598..ccba1fd4a4 100644 --- a/device_tree.c +++ b/device_tree.c @@ -11,13 +11,13 @@ * */ -#include <stdio.h> -#include <sys/types.h> -#include <sys/stat.h> -#include <fcntl.h> -#include <unistd.h> -#include <stdlib.h> +#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" @@ -117,6 +117,102 @@ fail: 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; @@ -131,6 +227,60 @@ static int findnode_nofail(void *fdt, const char *node_path) 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) { @@ -184,31 +334,39 @@ int qemu_fdt_setprop_string(void *fdt, const char *node_path, } const void *qemu_fdt_getprop(void *fdt, const char *node_path, - const char *property, int *lenp) + 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_report("%s: Couldn't get %s/%s: %s", __func__, - node_path, property, fdt_strerror(*lenp)); - exit(1); + 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) + const char *property, int *lenp, Error **errp) { int len; - const uint32_t *p = qemu_fdt_getprop(fdt, node_path, property, &len); - if (len != 4) { - error_report("%s: %s/%s not 4 bytes long (not a cell?)", - __func__, node_path, property); - exit(1); + 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); } |