| // 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)); |
| } |
| |
| /** |
| * Shows a list of cells in the requested format |
| * |
| * @param disp Display information / options |
| * @param data Data to display |
| * @param len Maximum length of buffer |
| * @param size Data size to use for display (e.g. 4 for 32-bit) |
| * @return 0 if ok, -1 on error |
| */ |
| static int show_cell_list(struct display_info *disp, const char *data, int len, |
| int size) |
| { |
| const uint8_t *p = (const uint8_t *)data; |
| char fmt[3]; |
| int value; |
| int i; |
| |
| 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_ld((const fdt32_t *)p) : |
| size == 2 ? (*p << 8) | p[1] : *p; |
| printf(fmt, value); |
| } |
| |
| return 0; |
| } |
| |
| /** |
| * 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 size; |
| const char *s; |
| int is_string; |
| |
| /* 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; |
| } |
| |
| return show_cell_list(disp, data, len, size); |
| } |
| |
| /** |
| * 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 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; |
| fdt_getprop_by_offset(blob, prop, &name, NULL); |
| 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 |
| * @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, NULL); |
| 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); |
| free(blob); |
| return -1; |
| } |
| } |
| prop = args_per_step == 1 ? NULL : arg[i + 1]; |
| |
| if (show_data_for_item(blob, disp, node, prop)) { |
| free(blob); |
| return -1; |
| } |
| } |
| |
| free(blob); |
| |
| return 0; |
| } |
| |
| /* Usage related data. */ |
| static const char usage_synopsis[] = |
| "read values from device tree\n" |
| " fdtget <options> <dt file> [<node> <property>]...\n" |
| " fdtget -p <options> <dt file> [<node> ]...\n" |
| "\n" |
| "Each value is printed on a new line.\n" |
| USAGE_TYPE_MSG; |
| static const char usage_short_opts[] = "t:pld:" USAGE_COMMON_SHORT_OPTS; |
| static struct option const usage_long_opts[] = { |
| {"type", a_argument, NULL, 't'}, |
| {"properties", no_argument, NULL, 'p'}, |
| {"list", no_argument, NULL, 'l'}, |
| {"default", a_argument, NULL, 'd'}, |
| USAGE_COMMON_LONG_OPTS, |
| }; |
| static const char * const usage_opts_help[] = { |
| "Type of data", |
| "List properties for each node", |
| "List subnodes for each node", |
| "Default value to display when the property is missing", |
| USAGE_COMMON_OPTS_HELP |
| }; |
| |
| int main(int argc, char *argv[]) |
| { |
| int opt; |
| 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; |
| while ((opt = util_getopt_long()) != EOF) { |
| switch (opt) { |
| case_USAGE_COMMON_FLAGS |
| |
| 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; |
| } |