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-rw-r--r--scripts/dtc/fdtput.c348
1 files changed, 348 insertions, 0 deletions
diff --git a/scripts/dtc/fdtput.c b/scripts/dtc/fdtput.c
new file mode 100644
index 0000000000..a363c3cabc
--- /dev/null
+++ b/scripts/dtc/fdtput.c
@@ -0,0 +1,348 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
+ */
+
+#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;
+}