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Diffstat (limited to 'scripts/dtc/fdtget.c')
| -rw-r--r-- | scripts/dtc/fdtget.c | 366 | 
1 files changed, 366 insertions, 0 deletions
diff --git a/scripts/dtc/fdtget.c b/scripts/dtc/fdtget.c new file mode 100644 index 00000000000..c2fbab2a547 --- /dev/null +++ b/scripts/dtc/fdtget.c @@ -0,0 +1,366 @@ +/* + * 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> + * + * 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" + +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; +}  | 
