diff options
Diffstat (limited to 'softmmu/device_tree.c')
-rw-r--r-- | softmmu/device_tree.c | 644 |
1 files changed, 644 insertions, 0 deletions
diff --git a/softmmu/device_tree.c b/softmmu/device_tree.c new file mode 100644 index 000000000..3965c834c --- /dev/null +++ b/softmmu/device_tree.c @@ -0,0 +1,644 @@ +/* + * 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/error-report.h" +#include "qemu/option.h" +#include "qemu/bswap.h" +#include "qemu/cutils.h" +#include "sysemu/device_tree.h" +#include "hw/loader.h" +#include "hw/boards.h" +#include "qemu/config-file.h" + +#include <libfdt.h> + +#define FDT_MAX_SIZE 0x100000 + +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; + } + if (dt_size > INT_MAX / 2 - 10000) { + error_report("Device tree file '%s' is too large", 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_size(filename_path, fdt, dt_size); + 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_report("%s: %s must be searched within %s", + __func__, dirname, root_dir); + exit(1); + } + parent_node = &dirname[strlen(SYSFS_DT_BASEDIR)]; + + d = opendir(dirname); + if (!d) { + error_report("%s cannot open %s", __func__, dirname); + exit(1); + } + + 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_report("%s cannot lstat %s", __func__, tmpnam); + exit(1); + } + + if (S_ISREG(st.st_mode)) { + gchar *val; + gsize len; + + if (!g_file_get_contents(tmpnam, &val, &len, NULL)) { + error_report("%s not able to extract info from %s", + __func__, tmpnam); + exit(1); + } + + 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_report("%s host device tree extracted into memory is invalid", + __func__); + exit(1); + } + 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_unit_path(void *fdt, const char *name, Error **errp) +{ + char *prefix = g_strdup_printf("%s@", name); + unsigned int path_len = 16, n = 0; + GSList *path_list = NULL, *iter; + const char *iter_name; + int offset, len, ret; + char **path_array; + + offset = fdt_next_node(fdt, -1, NULL); + + while (offset >= 0) { + iter_name = fdt_get_name(fdt, offset, &len); + if (!iter_name) { + offset = len; + break; + } + if (!strcmp(iter_name, name) || g_str_has_prefix(iter_name, prefix)) { + 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_next_node(fdt, offset, NULL); + } + g_free(prefix); + + if (offset < 0 && offset != -FDT_ERR_NOTFOUND) { + error_setg(errp, "%s: abort parsing dt for %s node units: %s", + __func__, name, 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; +} + +char **qemu_fdt_node_path(void *fdt, const char *name, const 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 (!name || !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; +} + +/* + * libfdt doesn't allow us to add string arrays directly but they are + * test a series of null terminated strings with a length. We build + * the string up here so we can calculate the final length. + */ +int qemu_fdt_setprop_string_array(void *fdt, const char *node_path, + const char *prop, char **array, int len) +{ + int ret, i, total_len = 0; + char *str, *p; + for (i = 0; i < len; i++) { + total_len += strlen(array[i]) + 1; + } + p = str = g_malloc0(total_len); + for (i = 0; i < len; i++) { + int len = strlen(array[i]) + 1; + pstrcpy(p, len, array[i]); + p += len; + } + + ret = qemu_fdt_setprop(fdt, node_path, prop, str, total_len); + g_free(str); + return ret; +} + +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("%s: Failed to create subnode %s: %s", + __func__, name, fdt_strerror(retval)); + exit(1); + } + + g_free(dupname); + return retval; +} + +/* + * qemu_fdt_add_path: Like qemu_fdt_add_subnode(), but will add + * all missing subnodes from the given path. + */ +int qemu_fdt_add_path(void *fdt, const char *path) +{ + const char *name; + const char *p = path; + int namelen, retval; + int parent = 0; + + if (path[0] != '/') { + return -1; + } + + while (p) { + name = p + 1; + p = strchr(name, '/'); + namelen = p != NULL ? p - name : strlen(name); + + retval = fdt_subnode_offset_namelen(fdt, parent, name, namelen); + if (retval < 0 && retval != -FDT_ERR_NOTFOUND) { + error_report("%s: Unexpected error in finding subnode %.*s: %s", + __func__, namelen, name, fdt_strerror(retval)); + exit(1); + } else if (retval == -FDT_ERR_NOTFOUND) { + retval = fdt_add_subnode_namelen(fdt, parent, name, namelen); + if (retval < 0) { + error_report("%s: Failed to create subnode %.*s: %s", + __func__, namelen, name, fdt_strerror(retval)); + exit(1); + } + } + + parent = retval; + } + + return retval; +} + +void qemu_fdt_dumpdtb(void *fdt, int size) +{ + const char *dumpdtb = current_machine->dumpdtb; + + if (dumpdtb) { + /* Dump the dtb to a file and quit */ + if (g_file_set_contents(dumpdtb, fdt, size, NULL)) { + info_report("dtb dumped to %s. Exiting.", dumpdtb); + exit(0); + } + error_report("%s: Failed dumping dtb to %s", __func__, dumpdtb); + exit(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; +} |