From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Gibson Subject: Re: [PATCH v2 5/6] Add new fdtput utility to write values to fdt Date: Thu, 8 Sep 2011 15:32:09 +1000 Message-ID: <20110908053209.GT30278@yookeroo.fritz.box> References: <1315425260-2711-1-git-send-email-sjg@chromium.org> <1315425260-2711-6-git-send-email-sjg@chromium.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1315425260-2711-6-git-send-email-sjg-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: devicetree-discuss-bounces+gldd-devicetree-discuss=m.gmane.org-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org Sender: devicetree-discuss-bounces+gldd-devicetree-discuss=m.gmane.org-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org To: Simon Glass Cc: Devicetree Discuss List-Id: devicetree@vger.kernel.org On Wed, Sep 07, 2011 at 12:54:19PM -0700, Simon Glass wrote: > This simple utility allows writing of values into a device tree from the > command line. It aimes to be the opposite of fdtget. > > What is it for: > - Updating fdt values when a binary blob already exists > (even though source may be available it might be easier to use this > utility rather than sed, etc.) > - Writing machine-specific fdt values within a build system > > To use it, specify the fdt binary file on command line followed by the node > and property to set. Then, provide a list of values to put into that > property. Often there will be just one, but fdtput also supports arrays and > string lists. > > fdtput does not trit to guess the type of the property based on looking at > the arguments. Instead it always assumed that an integer is provided. To > indicate that you want to write a string, use -ts. You can also provide > hex values with -tx. > > The command line arguments are joined together into a single value. For > strings, a nul terminator is placed between each string. To avoid this, pass > the string as a single parameter. > > Usage: > fdtput
< [...] > Options: > -t [][] Type of data > -v Verbose: display each value decoded from command line > -h Print this help > > One character (s=string, i=int, u=unsigned, b=byte) > Optional format character (x=hex) > > To read from stdin and write to stdout, use - as the file. So you can do: > > cat somefile.dtb | fdtput -ts - /node prop "My string value" > newfile.dtb > > Signed-off-by: Simon Glass > --- > Changes in v2: > - Separate arguments for node and property > - Remove limits on data size of property writting to fdt > - Remove use of getopt_long() > > .gitignore | 1 + > Makefile | 6 ++ > Makefile.fdtput | 12 +++ > fdtput.c | 217 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ > 4 files changed, 236 insertions(+), 0 deletions(-) > create mode 100644 Makefile.fdtput > create mode 100644 fdtput.c > > diff --git a/.gitignore b/.gitignore > index 9f27f34..2c9a64e 100644 > --- a/.gitignore > +++ b/.gitignore > @@ -11,3 +11,4 @@ lex.yy.c > /convert-dtsv0 > /version_gen.h > /fdtget > +/fdtput > diff --git a/Makefile b/Makefile > index 3d460d7..c6b57d7 100644 > --- a/Makefile > +++ b/Makefile > @@ -107,11 +107,13 @@ include Makefile.convert-dtsv0 > include Makefile.dtc > include Makefile.ftdump > include Makefile.fdtget > +include Makefile.fdtput Separate makefile fragments for the two utilities seems overkill. Can't you just have one Makefile.utils or something. > > BIN += convert-dtsv0 > BIN += dtc > BIN += ftdump > BIN += fdtget > +BIN += fdtput > > SCRIPTS = dtdiff > > @@ -123,6 +125,7 @@ ifneq ($(DEPTARGETS),) > -include $(CONVERT_OBJS:%.o=%.d) > -include $(FTDUMP_OBJS:%.o=%.d) > -include $(FDTGET_OBJS:%.o=%.d) > +-include $(FDTPUT_OBJS:%.o=%.d) > endif > > > @@ -185,6 +188,9 @@ ftdump: $(FTDUMP_OBJS) $(LIBFDT_archive) > > fdtget: $(FDTGET_OBJS) $(LIBFDT_archive) > > +fdtput: $(FDTPUT_OBJS) $(LIBFDT_archive) > + > + > # > # Testsuite rules > # > diff --git a/Makefile.fdtput b/Makefile.fdtput > new file mode 100644 > index 0000000..de1cfdf > --- /dev/null > +++ b/Makefile.fdtput > @@ -0,0 +1,12 @@ > +# > +# This is not a complete Makefile. > +# Instead, it is designed to be easily embeddable > +# into other systems of Makefiles. > +# > + > +FDTPUT_SRCS = \ > + fdtput.c \ > + util.c \ > + utilfdt.c > + > +FDTPUT_OBJS = $(FDTPUT_SRCS:%.c=%.o) > diff --git a/fdtput.c b/fdtput.c > new file mode 100644 > index 0000000..fd03d76 > --- /dev/null > +++ b/fdtput.c > @@ -0,0 +1,217 @@ > +/* > + * Copyright (c) 2011 The Chromium OS Authors. All rights reserved. > + * Distributed under the terms of the GNU General Public License v2 > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > + > +#include > + > +#include "util.h" > +#include "utilfdt.h" > + > +struct display_info { > + int type; /* data type (s/i/u/b or 0 for default) */ > + int format; /* data format (x or 0 for default) */ > + int verbose; /* verbose output */ > +}; > + > +static void report_error(const char *where, int err) > +{ > + fprintf(stderr, "Error at '%s': %s\n", where, 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 */ > + > + upto = 0; > + > + if (disp->verbose) > + fprintf(stderr, "Decoding value:\n"); > + 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->type == 'b' ? 1 : 4; > + > + /* 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, disp->format == 'x' ? "%x" : "%d", &ival); > + if (len == 4) > + *iptr = cpu_to_fdt32(ival); > + else > + *ptr = (uint8_t)ival; > + if (disp->verbose) { > + fprintf(stderr, "\t%s: %d\n", > + disp->type == 'b' ? "byte" : "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, node); > + return -1; > + } > + > + err = fdt_setprop(blob, node, property, buf, len); > + if (err) { > + report_error(property, err); > + 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 = util_read_fdt(filename); > + if (!blob) > + return -1; > + > + /* convert the arguments into a single binary value, then store */ > + assert(arg_count >= 2); > + if (encode_value(disp, arg + 2, arg_count - 2, &value, &len) || > + store_key_value(blob, *arg, arg[1], value, len)) > + ret = -1; > + > + if (!ret) > + ret = util_write_fdt(blob, filename); > + > + 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
< [...]\n" > + "Options:\n" > + "\t-t [][]\tType of data\n" > + "\t-v\t\tVerbose: display each value decoded from command line\n" > + "\t-h\t\tPrint this help\n\n" > + "\t\t\tOne character (s=string, i=int, u=unsigned, b=byte)\n" > + "\t\tOptional format character (x=hex)\n"; > + > +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)); > + for (;;) { > + int c = getopt(argc, argv, "ht: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 'h': > + case '?': > + usage(""); > + > + case 't': > + if (utilfdt_decode_type(optarg, &disp.type, > + &disp.format)) > + 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 (argc < 1) > + usage("Missing node"); > + if (argc < 2) > + usage("Missing property"); > + > + if (do_fdtput(&disp, filename, argv, argc)) > + return 1; > + return 0; > +} -- David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson