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-rw-r--r--scripts/dtc/fdtget.c352
1 files changed, 352 insertions, 0 deletions
diff --git a/scripts/dtc/fdtget.c b/scripts/dtc/fdtget.c
new file mode 100644
index 000000000..c922f8224
--- /dev/null
+++ b/scripts/dtc/fdtget.c
@@ -0,0 +1,352 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
+ *
+ * Portions from U-Boot cmd_fdt.c (C) Copyright 2007
+ * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com
+ * Based on code written by:
+ * Pantelis Antoniou <pantelis.antoniou@gmail.com> and
+ * Matthew McClintock <msm@freescale.com>
+ */
+
+#include <assert.h>
+#include <ctype.h>
+#include <getopt.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <libfdt.h>
+
+#include "util.h"
+
+enum display_mode {
+ MODE_SHOW_VALUE, /* show values for node properties */
+ MODE_LIST_PROPS, /* list the properties for a node */
+ MODE_LIST_SUBNODES, /* list the subnodes of a node */
+};
+
+/* Holds information which controls our output and options */
+struct display_info {
+ int type; /* data type (s/i/u/x or 0 for default) */
+ int size; /* data size (1/2/4) */
+ enum display_mode mode; /* display mode that we are using */
+ const char *default_val; /* default value if node/property not found */
+};
+
+static void report_error(const char *where, int err)
+{
+ fprintf(stderr, "Error at '%s': %s\n", where, fdt_strerror(err));
+}
+
+/**
+ * Displays data of a given length according to selected options
+ *
+ * If a specific data type is provided in disp, then this is used. Otherwise
+ * we try to guess the data type / size from the contents.
+ *
+ * @param disp Display information / options
+ * @param data Data to display
+ * @param len Maximum length of buffer
+ * @return 0 if ok, -1 if data does not match format
+ */
+static int show_data(struct display_info *disp, const char *data, int len)
+{
+ int i, size;
+ const uint8_t *p = (const uint8_t *)data;
+ const char *s;
+ int value;
+ int is_string;
+ char fmt[3];
+
+ /* no data, don't print */
+ if (len == 0)
+ return 0;
+
+ is_string = (disp->type) == 's' ||
+ (!disp->type && util_is_printable_string(data, len));
+ if (is_string) {
+ if (data[len - 1] != '\0') {
+ fprintf(stderr, "Unterminated string\n");
+ return -1;
+ }
+ for (s = data; s - data < len; s += strlen(s) + 1) {
+ if (s != data)
+ printf(" ");
+ printf("%s", (const char *)s);
+ }
+ return 0;
+ }
+ size = disp->size;
+ if (size == -1) {
+ size = (len % 4) == 0 ? 4 : 1;
+ } else if (len % size) {
+ fprintf(stderr, "Property length must be a multiple of "
+ "selected data size\n");
+ return -1;
+ }
+ fmt[0] = '%';
+ fmt[1] = disp->type ? disp->type : 'd';
+ fmt[2] = '\0';
+ for (i = 0; i < len; i += size, p += size) {
+ if (i)
+ printf(" ");
+ value = size == 4 ? fdt32_to_cpu(*(const uint32_t *)p) :
+ size == 2 ? (*p << 8) | p[1] : *p;
+ printf(fmt, value);
+ }
+ return 0;
+}
+
+/**
+ * List all properties in a node, one per line.
+ *
+ * @param blob FDT blob
+ * @param node Node to display
+ * @return 0 if ok, or FDT_ERR... if not.
+ */
+static int list_properties(const void *blob, int node)
+{
+ const struct fdt_property *data;
+ const char *name;
+ int prop;
+
+ prop = fdt_first_property_offset(blob, node);
+ do {
+ /* Stop silently when there are no more properties */
+ if (prop < 0)
+ return prop == -FDT_ERR_NOTFOUND ? 0 : prop;
+ data = fdt_get_property_by_offset(blob, prop, NULL);
+ name = fdt_string(blob, fdt32_to_cpu(data->nameoff));
+ if (name)
+ puts(name);
+ prop = fdt_next_property_offset(blob, prop);
+ } while (1);
+}
+
+#define MAX_LEVEL 32 /* how deeply nested we will go */
+
+/**
+ * List all subnodes in a node, one per line
+ *
+ * @param blob FDT blob
+ * @param node Node to display
+ * @return 0 if ok, or FDT_ERR... if not.
+ */
+static int list_subnodes(const void *blob, int node)
+{
+ int nextoffset; /* next node offset from libfdt */
+ uint32_t tag; /* current tag */
+ int level = 0; /* keep track of nesting level */
+ const char *pathp;
+ int depth = 1; /* the assumed depth of this node */
+
+ while (level >= 0) {
+ tag = fdt_next_tag(blob, node, &nextoffset);
+ switch (tag) {
+ case FDT_BEGIN_NODE:
+ pathp = fdt_get_name(blob, node, NULL);
+ if (level <= depth) {
+ if (pathp == NULL)
+ pathp = "/* NULL pointer error */";
+ if (*pathp == '\0')
+ pathp = "/"; /* root is nameless */
+ if (level == 1)
+ puts(pathp);
+ }
+ level++;
+ if (level >= MAX_LEVEL) {
+ printf("Nested too deep, aborting.\n");
+ return 1;
+ }
+ break;
+ case FDT_END_NODE:
+ level--;
+ if (level == 0)
+ level = -1; /* exit the loop */
+ break;
+ case FDT_END:
+ return 1;
+ case FDT_PROP:
+ break;
+ default:
+ if (level <= depth)
+ printf("Unknown tag 0x%08X\n", tag);
+ return 1;
+ }
+ node = nextoffset;
+ }
+ return 0;
+}
+
+/**
+ * Show the data for a given node (and perhaps property) according to the
+ * display option provided.
+ *
+ * @param blob FDT blob
+ * @param disp Display information / options
+ * @param node Node to display
+ * @param property Name of property to display, or NULL if none
+ * @return 0 if ok, -ve on error
+ */
+static int show_data_for_item(const void *blob, struct display_info *disp,
+ int node, const char *property)
+{
+ const void *value = NULL;
+ int len, err = 0;
+
+ switch (disp->mode) {
+ case MODE_LIST_PROPS:
+ err = list_properties(blob, node);
+ break;
+
+ case MODE_LIST_SUBNODES:
+ err = list_subnodes(blob, node);
+ break;
+
+ default:
+ assert(property);
+ value = fdt_getprop(blob, node, property, &len);
+ if (value) {
+ if (show_data(disp, value, len))
+ err = -1;
+ else
+ printf("\n");
+ } else if (disp->default_val) {
+ puts(disp->default_val);
+ } else {
+ report_error(property, len);
+ err = -1;
+ }
+ break;
+ }
+
+ return err;
+}
+
+/**
+ * Run the main fdtget operation, given a filename and valid arguments
+ *
+ * @param disp Display information / options
+ * @param filename Filename of blob file
+ * @param arg List of arguments to process
+ * @param arg_count Number of arguments
+ * @param return 0 if ok, -ve on error
+ */
+static int do_fdtget(struct display_info *disp, const char *filename,
+ char **arg, int arg_count, int args_per_step)
+{
+ char *blob;
+ const char *prop;
+ int i, node;
+
+ blob = utilfdt_read(filename);
+ if (!blob)
+ return -1;
+
+ for (i = 0; i + args_per_step <= arg_count; i += args_per_step) {
+ node = fdt_path_offset(blob, arg[i]);
+ if (node < 0) {
+ if (disp->default_val) {
+ puts(disp->default_val);
+ continue;
+ } else {
+ report_error(arg[i], node);
+ return -1;
+ }
+ }
+ prop = args_per_step == 1 ? NULL : arg[i + 1];
+
+ if (show_data_for_item(blob, disp, node, prop))
+ return -1;
+ }
+ return 0;
+}
+
+static const char *usage_msg =
+ "fdtget - read values from device tree\n"
+ "\n"
+ "Each value is printed on a new line.\n\n"
+ "Usage:\n"
+ " fdtget <options> <dt file> [<node> <property>]...\n"
+ " fdtget -p <options> <dt file> [<node> ]...\n"
+ "Options:\n"
+ "\t-t <type>\tType of data\n"
+ "\t-p\t\tList properties for each node\n"
+ "\t-l\t\tList subnodes for each node\n"
+ "\t-d\t\tDefault value to display when the property is "
+ "missing\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[])
+{
+ char *filename = NULL;
+ struct display_info disp;
+ int args_per_step = 2;
+
+ /* set defaults */
+ memset(&disp, '\0', sizeof(disp));
+ disp.size = -1;
+ disp.mode = MODE_SHOW_VALUE;
+ for (;;) {
+ int c = getopt(argc, argv, "d:hlpt:");
+ if (c == -1)
+ break;
+
+ switch (c) {
+ case 'h':
+ case '?':
+ usage(NULL);
+
+ case 't':
+ if (utilfdt_decode_type(optarg, &disp.type,
+ &disp.size))
+ usage("Invalid type string");
+ break;
+
+ case 'p':
+ disp.mode = MODE_LIST_PROPS;
+ args_per_step = 1;
+ break;
+
+ case 'l':
+ disp.mode = MODE_LIST_SUBNODES;
+ args_per_step = 1;
+ break;
+
+ case 'd':
+ disp.default_val = optarg;
+ break;
+ }
+ }
+
+ if (optind < argc)
+ filename = argv[optind++];
+ if (!filename)
+ usage("Missing filename");
+
+ argv += optind;
+ argc -= optind;
+
+ /* Allow no arguments, and silently succeed */
+ if (!argc)
+ return 0;
+
+ /* Check for node, property arguments */
+ if (args_per_step == 2 && (argc % 2))
+ usage("Must have an even number of arguments");
+
+ if (do_fdtget(&disp, filename, argv, argc, args_per_step))
+ return 1;
+ return 0;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-10-30 01:42:10 +0000