Commit graph

89 commits

Author SHA1 Message Date
Patrick Oppenlander
2478b1652c libfdt: add extern "C" for C++
Signed-off-by: Patrick Oppenlander <patrick.oppenlander@gmail.com>
Message-Id: <20200616011217.15253-1-patrick.oppenlander@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-06-19 09:52:41 +10:00
Simon Glass
0c5326cb28 libfdt: De-inline fdt_header_size()
There does not seem to be a strong reason to inline this function. Also
we are about to add some extra code to it which will increase its size.

Move it into fdt.c and use a simple declaration in libfdt.h

Signed-off-by: Simon Glass <sjg@chromium.org>
Message-Id: <20200220214557.176528-2-sjg@chromium.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-02-24 13:38:44 +11:00
Luc Michel
67f790c1ad libfdt.h: add explicit cast from void* to uint8_t* in fdt(32|64)_st
Including libfdt.h in a C++ project fails during compilation with recent
version of GCC or Clang.

This simple example:

extern "C" {
 #include <libfdt.h>
}

int main(void) { return 0; }

leads to the following errors with GCC 9.1.0:

/usr/include/libfdt.h: In function ‘void fdt32_st(void*, uint32_t)’:
/usr/include/libfdt.h:139:16: error: invalid conversion from ‘void*’ to ‘uint8_t*’ {aka ‘unsigned char*’} [-fpermissive]
  139 |  uint8_t *bp = property;
      |                ^~~~~~~~
      |                |
      |                void*
/usr/include/libfdt.h: In function ‘void fdt64_st(void*, uint64_t)’:
/usr/include/libfdt.h:163:16: error: invalid conversion from ‘void*’ to ‘uint8_t*’ {aka ‘unsigned char*’} [-fpermissive]
  163 |  uint8_t *bp = property;
      |                ^~~~~~~~
      |                |
      |                void*

This commit adds an explicit cast to uint8_t* to fix this issue.

Signed-off-by: Luc Michel <luc.michel@greensocs.com>
Message-Id: <20190910104824.1321594-1-luc.michel@greensocs.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-09-10 23:11:40 +10:00
Rob Herring
7fb0f4db2e libfdt: Replace GPL/BSD boilerplate/reference with SPDX tags
Replace instances of dual GPLv2 or BSD license boilerplate with SPDX tags.

Signed-off-by: Rob Herring <robh@kernel.org>
Message-Id: <20190620211944.9378-3-robh@kernel.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-06-21 21:06:10 +10:00
Nicholas Piggin
ce01b21098 libfdt: Add FDT_CREATE_FLAG_NO_NAME_DEDUP flag that trades size for speed
Searching for duplicate names scales O(n^2) with the number of names
added to a fdt, which can cause a noticable slowdown with larger device
trees and very slow CPU cores.

Add FDT_CREATE_FLAG_NO_NAME_DEDUP that allow the caller to trade fdt size
for speed in the creation process.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20190509094122.834-4-npiggin@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-05-10 11:53:10 +10:00
Nicholas Piggin
fbb62754ce libfdt: Introduce fdt_create_with_flags()
There is a need to be able to specify some options when building an FDT
with the SW interface. This can be accomplished with minimal changes by
storing intermediate data in the fdt header itself, in fields that are
not otherwise needed during the creation process and can be set by
fdt_finish().

The fdt.magic field is already used exactly this way, as a state to
check with callers that the FDT has been created but not yet finished.

fdt.version and fdt.last_comp_version are used to make room for more
intermediate state. These are adjacent and unused during the building
process. last_comp_version is not yet used for intermediate state, but
it is zeroed and treated as used, so as to allow future growth easily.

A new interface, fdt_create_with_flags() is added, which takes 32-bit
flag value to control creation.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20190509094122.834-3-npiggin@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-05-10 11:53:10 +10:00
David Gibson
cca6546244 libfdt: Make fdt_get_max_phandle() an inline
It's now a trivial wrapper around fdt_find_max_phandle() so we might as
well inline it.  We also remove it from the versioning linker script.
Theoretically, that's a breaking ABI change except that we haven't yet
released a version with it exposed in the shared object, so we can get
away with it.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-03-29 13:59:04 +11:00
Thierry Reding
730875016a libfdt: Add phandle generation helper
The new fdt_generate_phandle() function can be used to generate a new,
unused phandle given a specific device tree blob. The implementation is
somewhat naive in that it simply walks the entire device tree to find
the highest phandle value and then returns a phandle value one higher
than that. A more clever implementation might try to find holes in the
current set of phandle values and fill them. But this implementation is
relatively simple and works reliably.

Also add a test that validates that phandles generated by this new API
are indeed unique.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Message-Id: <20190326153302.17109-3-thierry.reding@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-03-29 13:31:16 +11:00
Thierry Reding
2bc5b66d7f libfdt: Add new maximum phandle lookup function
The fdt_get_max_phandle() function has some shortcomings. On one hand
it returns just a uint32_t which means to check for the "negative"
error code a caller has to explicitly check against the error code
(uint32_t)-1. In addition, the -1 is the only error code that can be
returned, so a caller cannot tell the difference between the various
failures.

Fix this by adding a new fdt_find_max_phandle() function that returns an
error code on failure and 0 on success, just like other APIs, and stores
the maximum phandle value in an output argument on success.

This also refactors fdt_get_max_phandle() to use the new function. Add a
note pointing out that the new fdt_find_max_phandle() function should be
preferred over fdt_get_max_phandle().

Signed-off-by: Thierry Reding <treding@nvidia.com>
Message-Id: <20190326153302.17109-1-thierry.reding@gmail.com>
[dwg: Reword for some inaccuracies in the commit message]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-03-29 13:29:51 +11:00
AKASHI Takahiro
7fcf8208b8 libfdt: add fdt_append_addrrange()
This function will append an address range property using parent node's
"#address-cells" and "#size-cells" properties.

It will be used in implementing kdump with kexec_file_load system call
at linux kernel for arm64 once it is merged into kernel tree.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Message-Id: <20190327061552.17170-2-takahiro.akashi@linaro.org>
[dwg: Correct a SEGV error in the testcase]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-03-29 12:12:29 +11:00
David Gibson
f67b471355 Revert "libfdt: Add phandle generation helper"
This reverts commit 54ea41c224.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-03-25 14:51:27 +11:00
Thierry Reding
54ea41c224 libfdt: Add phandle generation helper
The new fdt_generate_phandle() function can be used to generate a new,
unused phandle given a specific device tree blob. The implementation is
somewhat naive in that it simply walks the entire device tree to find
the highest phandle value and then returns a phandle value one higher
than that. A more clever implementation might try to find holes in the
current set of phandle values and fill them. But this implementation is
relatively simple and works reliably.

Also add a test that validates that phandles generated by this new API
are indeed unique.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Message-Id: <20190320151003.28941-1-thierry.reding@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-03-21 11:37:44 +11:00
Geert Uytterhoeven
ea7a8f6dad libfdt: Fix FDT_ERR_NOTFOUND typos in documentation
The actual error is FDT_ERR_NOTFOUND, not FDT_ERR_NOT_FOUND.

Fixes: d29126c90a ("libfdt: Add iterator over properties")
Fixes: 902d0f0953 ("libfdt: Add a subnodes iterator macro")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-12-23 13:34:57 +11:00
Geert Uytterhoeven
5aafd7ca43 libfdt: Fix fdt_getprop_by_offset() parameter name in documentation
The second parameter of fdt_getprop_by_offset() is called "offset", not
"ffset".

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-12-22 00:02:58 +11:00
David Gibson
11738cf01f libfdt: Don't use memcpy to handle unaligned reads on ARM
6dcb8ba4 "libfdt: Add helpers for accessing unaligned words" introduced
the fdt32_ld() and fdt64_ld() helpers for loading values from the FDT blob
which might not be naturally aligned.  This matters for ARM, where
attempting a plain unaligned load will often cause an exception.

However, it seems the memcpy() we used here was surprisingly expensive,
making libfdt nearly 6x slower on at least some ARM platforms.

This patch takes an alternative approach, using a bunch of 1-byte loads
and shifts to implement the helpers.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-11-22 23:37:07 +11:00
John Clarke
aa7254d9cb libfdt: return correct value if #size-cells property is not present
According to the device tree specification, the default value for
#size-cells is 1, but fdt_size_cells() was returning 2 if this property
was not present.

This patch also makes fdt_address_cells() and fdt_size_cells() conform
to the behaviour documented in libfdt.h. The defaults are only returned
if fdt_getprop() returns -FDT_ERR_NOTFOUND, otherwise the actual error
is returned.

Signed-off-by: John Clarke <johnc@kirriwa.net>
2018-11-07 14:13:12 +11:00
Sebastian Huber
c12b2b0c20 libfdt: fdt_address_cells() and fdt_size_cells()
Add internal fdt_cells() to avoid copy and paste.  Test error cases and
default values.  Fix typo in fdt_size_cells() documentation comment.

Signed-off-by: Sebastian Huber <sebastian.huber@embedded-brains.de>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-07-20 11:56:49 +10:00
David Gibson
6dcb8ba408 libfdt: Add helpers for accessing unaligned words
This adds some helpers to load (32 or 64 bit) words from an fdt blob, even
if they're unaligned and we're on a platform that doesn't like plain
unaligned loads and stores.  We then use the helpers in a number of places.
There are two purposes for this:

1) This makes libfdt more robust against a blob loaded at an unaligned
   address.  It's usually good practice to load a blob at a 64-bit
   alignment, but it's nice to work even then.

2) Users can use these helpers to load integer values from within property
   values.  These can often be unaligned, even if the blob as a whole is
   aligned, since some property encodings have integers and strings mixed
   together without any alignment gaps.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-06-26 15:09:46 +10:00
Simon Glass
9aafa33d99 pylibfdt: Add functions to update properties
Allow updating and creating properties, including special methods for
integers.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-06-12 14:44:20 +10:00
David Gibson
4b8fcc3d01 libfdt: Add fdt_check_full() function
This new function implements a complete and thorough check of an fdt blob's
structure.  Given a buffer containing an fdt, it should return 0 only if
the fdt within is structurally sound in all regards.  It doesn't check
anything about the blob's contents (i.e. the actual values of the nodes and
properties), of course.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Simon Glass <sjg@chromium.org>
2018-06-07 11:49:17 +10:00
David Gibson
0112fda03b libfdt: Add fdt_header_size()
We have a couple of places within libfdt and its tests where we need to
find the size of the header, based on the version.  Add a helper function
for it.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
2018-06-07 11:49:14 +10:00
David Gibson
70166d62a2 libfdt: Safer access to strings section
fdt_string() is used to retrieve strings from a DT blob's strings section.
It's rarely used directly, but is widely used internally.

However, it doesn't do any bounds checking, which means in the case of a
corrupted blob it could access bad memory, which libfdt is supposed to
avoid.

This write a safe alternative to fdt_string, fdt_get_string().  It checks
both that the given offset is within the string section and that the string
it points to is properly \0 terminated within the section.  It also returns
the string's length as a convenience (since it needs to determine to do the
checks anyway).

fdt_string() is rewritten in terms of fdt_get_string() for compatibility.

Most of the diff here is actually testing infrastructure.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
2018-06-07 11:48:20 +10:00
David Gibson
eb890c0f77 libfdt: Make fdt_check_header() more thorough
Currently fdt_check_header() performs only some rudimentary checks, which
is not really what the name suggests.  This strengthens fdt_check_header()
to check as much about the blob as is possible from the header alone:  as
well as checking the magic number and version, it checks that the total
size is sane, and that all the sub-blocks within the blob lie within the
total size.

 * This broadens the meaning of FDT_ERR_TRUNCATED to cover all sorts of
   improperly terminated blocks as well as just a structure block without
   FDT_END.

 * This makes fdt_check_header() only succeed on "complete" blobs, not
   in-progress sequential write blobs.  The only reason this didn't fail
   before was that this function used to be called by many RO functions
   which are supposed to also work on incomplete SW blobs.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Simon Glass <sjg@chromium.org>
2018-06-07 11:47:59 +10:00
Nathan Whitehorn
f1879e1a50 Add limited read-only support for older (V2 and V3) device tree to libfdt.
This can be useful in particular in the kernel when booting on systems
with FDT-emitting firmware that is out of date. Releases of kexec-tools
on ppc64 prior to the end of 2014 are notable examples of such.

Signed-off-by: Nathan Whitehorn <nwhitehorn@freebsd.org>
[dwg: Some whitespace cleanups]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-01-27 18:43:21 +11:00
David Gibson
c8b38f65fd libfdt: Remove leading underscores from identifiers
In a lot of places libfdt uses a leading _ character to mark an identifier
as "internal" (not part of the published libfdt API).  This is a bad idea,
because identifiers with a leading _ are generally reserved by the C
library or system.  It's particularly dangerous for libfdt, because it's
designed to be able to be integrated into lots of different environments.

In some cases the leading _ has no purpose, so we simply drop it.  In most
cases we move it to the end, as our new convention for marking internal
identifiers.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-10-26 09:25:14 +02:00
David Gibson
2e6fe5a107 Fix some errors in comments
A comment in tests/stringlist.c refers to fdt_get_string(), which is not a
function that exists.  From the content, it's supposed to be referring to
fdt_getprop_string().

A comment in libfdt.h has an extraneous space in a function name.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-10-26 09:25:14 +02:00
Pantelis Antoniou
a33c2247ac Introduce fdt_setprop_placeholder() method
In some cases you need to add a property but the contents of it
are not known at creation time, merely the extend of it.

This method allows you to create a property of a given size (filled
with garbage) while a pointer to the property data will be provided.

Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
[dwg: Corrected commit message]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-07-28 14:34:36 +10:00
Simon Glass
580a9f6c28 Add a libfdt function to write a property placeholder
The existing function to add a new property to a tree being built requires
that the entire contents of the new property be passed in. For some
applications it is more convenient to be able to add the property contents
later, perhaps by reading from a file. This avoids double-buffering of the
contents.

Add a new function to support this and adjust the existing fdt_property() to
use it.
Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-04-02 13:38:46 +10:00
Simon Glass
8cb3896358 Adjust libfdt.h to work with swig
There are a few places where libfdt.h cannot be used as is with swig:

- macros like fdt_totalsize() have to be defined as C declarations
- fdt_offset_ptr() and fdt_getprop_namelen() need special treatment due to
    a TODO in the wrapper for fdt_getprop(). However they are not useful to
    Python so can be removed

Add #ifdefs to work around these problem.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-03-21 16:21:58 +11:00
David Gibson
397d5ef020 libfdt: Add fdt_setprop_empty()
Device trees can contain empty (zero length) properties, which are often
used as boolean flags.  These can already be created using fdt_setprop()
passing a length of zero and a pointer which is ignored.  It is safe to
pass NULL, but that may not be obvious from the interface.  To make it
clearer, add an fdt_setprop_empty() helper macro.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2017-02-24 11:12:50 +11:00
Maxime Ripard
0cdd06c513 libfdt: Add overlay application function
The device tree overlays are a good way to deal with user-modifyable
boards or boards with some kind of an expansion mechanism where we can
easily plug new board in (like the BBB, the Raspberry Pi or the CHIP).

Add a new function to merge overlays with a base device tree.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-10-06 19:22:41 +11:00
Maxime Ripard
39240cc865 libfdt: Extend the reach of FDT_ERR_BADPHANDLE
So far, the BADPHANDLE error was only used for incorrect phandle values.
Extend that meaning to an improperly formatted phandle property.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-10-06 19:22:41 +11:00
Maxime Ripard
4aa3a6f5e6 libfdt: Add new errors for the overlay code
Add a few new error codes to report the failure conditions we might
encounter in the overlay application code:
   - FDT_ERR_BADOVERLAY, when an overlay cannot be parsed, even though its
     structure is correct
   - FDT_ERR_NOPHANDLES, when we ran out of available phandles and we
     cannot use a new phandle without either using an invalid one (-1 or
     0), or one already used.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-10-06 19:22:41 +11:00
Thomas Huth
45fd440a95 Fix some typing errors in libfdt.h and livetree.c
Correct some typos discovered with the codespell utility.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-09-27 11:32:46 +10:00
Maxime Ripard
d877364e4a libfdt: Add fdt_setprop_inplace_namelen_partial
Add a function to modify inplace only a portion of a property..

This is especially useful when the property is an array of values, and you
want to update one of them without changing the DT size.

Acked-by: Simon Glass <sjg@chromium.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
[dwg: Remove unnecessary unsigned qualifier, correct a comment]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-08-01 13:34:39 +10:00
Maxime Ripard
3e9037aaad libfdt: Add fdt_getprop_namelen_w
Add a function to retrieve a writeable property only by the first
characters of its name.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-07-28 15:29:16 +10:00
Maxime Ripard
84e0e1346c libfdt: Add max phandle retrieval function
Add a function to retrieve the highest phandle in a given device tree.

Acked-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Stefan Agner <stefan@agner.ch>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-07-28 15:29:16 +10:00
Maxime Ripard
d29126c90a libfdt: Add iterator over properties
Implement a macro based on fdt_first_property_offset and
fdt_next_property_offset that provides a convenience to iterate over all
the properties of a given node.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Simon Glass <sjg@chromium.org>
[dwg: Removed a stray trailing blank line]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-07-28 15:29:13 +10:00
Thierry Reding
902d0f0953 libfdt: Add a subnodes iterator macro
The fdt_for_each_subnode() iterator macro provided by this patch can be
used to iterate over a device tree node's subnodes. At each iteration a
loop variable will be set to the next subnode.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-07-28 15:27:57 +10:00
Simon Glass
beef80b8b5 Correct a missing space in a fdt_header cast
The code style here is slightly incorrect. Fix it.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-03-07 15:34:00 +11:00
Simon Glass
68d43cec12 Correct line lengths in libfdt.h
There are a few lines that are over 80 columns. Fix these.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-03-07 15:33:59 +11:00
Simon Glass
b0dbceafd4 Correct space-after-tab in libfdt.h
There are a few places with a space before a tab in this file. Fix them.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2016-03-07 15:33:59 +11:00
Thierry Reding
604e61e081 fdt: Add functions to retrieve strings
Given a device tree node, a property name and an index, the new function
fdt_stringlist_get() will return a pointer to the index'th string in the
property's value and return its length (or an error code on failure) in
an output argument.

Signed-off-by: Thierry Reding <treding@nvidia.com>
[Fix some -Wshadow warnings --dwg]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2015-09-30 13:26:31 +10:00
Thierry Reding
8702bd1d3b fdt: Add a function to get the index of a string
The new fdt_stringlist_search() function will look up a given string in
the list contained in the value of a named property of a given device
tree node and return its index.

Signed-off-by: Thierry Reding <treding@nvidia.com>
[Fix some -Wshadow warnings --dwg]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2015-09-30 13:26:18 +10:00
Thierry Reding
2218387a8c fdt: Add a function to count strings
Given a device tree node and a property name, the fdt_stringlist_count()
function counts the number of strings found in the property value.

This also adds a new error code, FDT_ERR_BADVALUE, that the function
returns when it encounters a non-NUL-terminated string list.

Signed-off-by: Thierry Reding <treding@nvidia.com>
[Changed testcase name --dwg]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2015-09-30 13:16:35 +10:00
Masahiro Yamada
554fde2c77 libfdt: fix comment block of fdt_get_property_namelen()
The statement "Identical to fdt_get_property_namelen() ..." does not
make sense for the comment of fdt_get_property_namelen() itself.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2015-08-27 17:14:15 +10:00
Peter Hurley
b4150b59ae libfdt: Add fdt_path_offset_namelen()
Properties may contain path names which are not NUL-terminated.
For example, the 'stdout-path' property allows the form 'path:options',
where the ':' character terminates the path specifier.

Allow these path names to be used in-place for path descending;
add fdt_path_offset_namelen(), which limits the path name to 'namelen'
characters.

Reimplement fdt_path_offset() as a trivial wrapper.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
2015-04-07 14:11:47 +10:00
David Gibson
40f7f576c8 libfdt: Add helpers to read #address-cells and #size-cells
This patch makes a small start on libfdt functions which actually help to
parse the contents of device trees, rather than purely manipulating the
tree's structure.

We add simple helpers to read and sanity check the #address-cells and
#size-cells values for a given node.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2014-05-12 16:01:09 +10:00
David Gibson
79eebb23db libfdt: Add function to resize the buffer for a sequential write tree
At present, when using sequential write mode, there's no straightforward
means of resizing the buffer the fdt is being built into.  This patch
adds an fdt_resize() function for this purpose.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2013-10-26 00:17:37 +11:00
Simon Glass
4e76ec796c libfdt: Add fdt_next_subnode() to permit easy subnode iteration
Iterating through subnodes with libfdt is a little painful to write as we
need something like this:

for (depth = 0, count = 0,
	offset = fdt_next_node(fdt, parent_offset, &depth);
     (offset >= 0) && (depth > 0);
     offset = fdt_next_node(fdt, offset, &depth)) {
	if (depth == 1) {
		/* code body */
	}
}

Using fdt_next_subnode() we can instead write this, which is shorter and
easier to get right:

for (offset = fdt_first_subnode(fdt, parent_offset);
     offset >= 0;
     offset = fdt_next_subnode(fdt, offset)) {
	/* code body */
}

Also, it doesn't require two levels of indentation for the loop body.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
2013-04-28 07:30:49 -05:00