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Diffstat (limited to 'scripts/dtc/fdtput.c')
-rw-r--r-- | scripts/dtc/fdtput.c | 362 |
1 files changed, 362 insertions, 0 deletions
diff --git a/scripts/dtc/fdtput.c b/scripts/dtc/fdtput.c new file mode 100644 index 0000000..f2197f5 --- /dev/null +++ b/scripts/dtc/fdtput.c @@ -0,0 +1,362 @@ +/* + * Copyright (c) 2011 The Chromium OS Authors. All rights reserved. + * + * 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 <ctype.h> +#include <getopt.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include <libfdt.h> + +#include "util.h" + +/* These are the operations we support */ +enum oper_type { + OPER_WRITE_PROP, /* Write a property in a node */ + OPER_CREATE_NODE, /* Create a new node */ +}; + +struct display_info { + enum oper_type oper; /* operation to perform */ + int type; /* data type (s/i/u/x or 0 for default) */ + int size; /* data size (1/2/4) */ + int verbose; /* verbose output */ + int auto_path; /* automatically create all path components */ +}; + + +/** + * Report an error with a particular node. + * + * @param name Node name to report error on + * @param namelen Length of node name, or -1 to use entire string + * @param err Error number to report (-FDT_ERR_...) + */ +static void report_error(const char *name, int namelen, int err) +{ + if (namelen == -1) + namelen = strlen(name); + fprintf(stderr, "Error at '%1.*s': %s\n", namelen, name, + fdt_strerror(err)); +} + +/** + * Encode a series of arguments in a property value. + * + * @param disp Display information / options + * @param arg List of arguments from command line + * @param arg_count Number of arguments (may be 0) + * @param valuep Returns buffer containing value + * @param *value_len Returns length of value encoded + */ +static int encode_value(struct display_info *disp, char **arg, int arg_count, + char **valuep, int *value_len) +{ + char *value = NULL; /* holding area for value */ + int value_size = 0; /* size of holding area */ + char *ptr; /* pointer to current value position */ + int len; /* length of this cell/string/byte */ + int ival; + int upto; /* the number of bytes we have written to buf */ + char fmt[3]; + + upto = 0; + + if (disp->verbose) + fprintf(stderr, "Decoding value:\n"); + + fmt[0] = '%'; + fmt[1] = disp->type ? disp->type : 'd'; + fmt[2] = '\0'; + for (; arg_count > 0; arg++, arg_count--, upto += len) { + /* assume integer unless told otherwise */ + if (disp->type == 's') + len = strlen(*arg) + 1; + else + len = disp->size == -1 ? 4 : disp->size; + + /* enlarge our value buffer by a suitable margin if needed */ + if (upto + len > value_size) { + value_size = (upto + len) + 500; + value = realloc(value, value_size); + if (!value) { + fprintf(stderr, "Out of mmory: cannot alloc " + "%d bytes\n", value_size); + return -1; + } + } + + ptr = value + upto; + if (disp->type == 's') { + memcpy(ptr, *arg, len); + if (disp->verbose) + fprintf(stderr, "\tstring: '%s'\n", ptr); + } else { + int *iptr = (int *)ptr; + sscanf(*arg, fmt, &ival); + if (len == 4) + *iptr = cpu_to_fdt32(ival); + else + *ptr = (uint8_t)ival; + if (disp->verbose) { + fprintf(stderr, "\t%s: %d\n", + disp->size == 1 ? "byte" : + disp->size == 2 ? "short" : "int", + ival); + } + } + } + *value_len = upto; + *valuep = value; + if (disp->verbose) + fprintf(stderr, "Value size %d\n", upto); + return 0; +} + +static int store_key_value(void *blob, const char *node_name, + const char *property, const char *buf, int len) +{ + int node; + int err; + + node = fdt_path_offset(blob, node_name); + if (node < 0) { + report_error(node_name, -1, node); + return -1; + } + + err = fdt_setprop(blob, node, property, buf, len); + if (err) { + report_error(property, -1, err); + return -1; + } + return 0; +} + +/** + * Create paths as needed for all components of a path + * + * Any components of the path that do not exist are created. Errors are + * reported. + * + * @param blob FDT blob to write into + * @param in_path Path to process + * @return 0 if ok, -1 on error + */ +static int create_paths(void *blob, const char *in_path) +{ + const char *path = in_path; + const char *sep; + int node, offset = 0; + + /* skip leading '/' */ + while (*path == '/') + path++; + + for (sep = path; *sep; path = sep + 1, offset = node) { + /* equivalent to strchrnul(), but it requires _GNU_SOURCE */ + sep = strchr(path, '/'); + if (!sep) + sep = path + strlen(path); + + node = fdt_subnode_offset_namelen(blob, offset, path, + sep - path); + if (node == -FDT_ERR_NOTFOUND) { + node = fdt_add_subnode_namelen(blob, offset, path, + sep - path); + } + if (node < 0) { + report_error(path, sep - path, node); + return -1; + } + } + + return 0; +} + +/** + * Create a new node in the fdt. + * + * This will overwrite the node_name string. Any error is reported. + * + * TODO: Perhaps create fdt_path_offset_namelen() so we don't need to do this. + * + * @param blob FDT blob to write into + * @param node_name Name of node to create + * @return new node offset if found, or -1 on failure + */ +static int create_node(void *blob, const char *node_name) +{ + int node = 0; + char *p; + + p = strrchr(node_name, '/'); + if (!p) { + report_error(node_name, -1, -FDT_ERR_BADPATH); + return -1; + } + *p = '\0'; + + if (p > node_name) { + node = fdt_path_offset(blob, node_name); + if (node < 0) { + report_error(node_name, -1, node); + return -1; + } + } + + node = fdt_add_subnode(blob, node, p + 1); + if (node < 0) { + report_error(p + 1, -1, node); + return -1; + } + + return 0; +} + +static int do_fdtput(struct display_info *disp, const char *filename, + char **arg, int arg_count) +{ + char *value; + char *blob; + int len, ret = 0; + + blob = utilfdt_read(filename); + if (!blob) + return -1; + + switch (disp->oper) { + case OPER_WRITE_PROP: + /* + * Convert the arguments into a single binary value, then + * store them into the property. + */ + assert(arg_count >= 2); + if (disp->auto_path && create_paths(blob, *arg)) + return -1; + if (encode_value(disp, arg + 2, arg_count - 2, &value, &len) || + store_key_value(blob, *arg, arg[1], value, len)) + ret = -1; + break; + case OPER_CREATE_NODE: + for (; ret >= 0 && arg_count--; arg++) { + if (disp->auto_path) + ret = create_paths(blob, *arg); + else + ret = create_node(blob, *arg); + } + break; + } + if (ret >= 0) + ret = utilfdt_write(filename, blob); + + free(blob); + return ret; +} + +static const char *usage_msg = + "fdtput - write a property value to a device tree\n" + "\n" + "The command line arguments are joined together into a single value.\n" + "\n" + "Usage:\n" + " fdtput <options> <dt file> <node> <property> [<value>...]\n" + " fdtput -c <options> <dt file> [<node>...]\n" + "Options:\n" + "\t-c\t\tCreate nodes if they don't already exist\n" + "\t-p\t\tAutomatically create nodes as needed for the node path\n" + "\t-t <type>\tType of data\n" + "\t-v\t\tVerbose: display each value decoded from command line\n" + "\t-h\t\tPrint this help\n\n" + USAGE_TYPE_MSG; + +static void usage(const char *msg) +{ + if (msg) + fprintf(stderr, "Error: %s\n\n", msg); + + fprintf(stderr, "%s", usage_msg); + exit(2); +} + +int main(int argc, char *argv[]) +{ + struct display_info disp; + char *filename = NULL; + + memset(&disp, '\0', sizeof(disp)); + disp.size = -1; + disp.oper = OPER_WRITE_PROP; + for (;;) { + int c = getopt(argc, argv, "chpt:v"); + if (c == -1) + break; + + /* + * TODO: add options to: + * - delete property + * - delete node (optionally recursively) + * - rename node + * - pack fdt before writing + * - set amount of free space when writing + * - expand fdt if value doesn't fit + */ + switch (c) { + case 'c': + disp.oper = OPER_CREATE_NODE; + break; + case 'h': + case '?': + usage(NULL); + case 'p': + disp.auto_path = 1; + break; + case 't': + if (utilfdt_decode_type(optarg, &disp.type, + &disp.size)) + usage("Invalid type string"); + break; + + case 'v': + disp.verbose = 1; + break; + } + } + + if (optind < argc) + filename = argv[optind++]; + if (!filename) + usage("Missing filename"); + + argv += optind; + argc -= optind; + + if (disp.oper == OPER_WRITE_PROP) { + if (argc < 1) + usage("Missing node"); + if (argc < 2) + usage("Missing property"); + } + + if (do_fdtput(&disp, filename, argv, argc)) + return 1; + return 0; +} |