[PATCH] tools/libfdt/fdt_rw: sync SPDX-License-Identifier with libfdt

[Quentin Schulz]

Hi Max,

On 8/14/25 2:03 PM, Max Merchel wrote:
> [You don't often get email from max.merchel at ew.tq-group.com. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ]
> 
> Currently, the terms of both licenses (GPL 2.0 and BSD-3 clause) must be met.

BSD-2-Clause and not BSD-3-Clause.

> However, libfdt uses OR to allow the choice of license used for the project.
> 
> [https://git.kernel.org/pub/scm/utils/dtc/dtc.git/tree/libfdt/fdt_rw.c?h=main&id=739403f222420a2fade2f939d001f51da473b6af]
> 

Technically, the written code isn't part of libfdt and in a separate 
file from it. However, it was actually part of the libfdt_rw file as 
imported from dtc, under the same license.

libfdt_rw initially was released under LGPL-2.1-or-later but got 
relicensed in 2007 to GPL-2.0-or-later OR BSD-2-Clause. According to 
db405d1980e0e3bfdd629399d1dfe457f1f32646, we are in sync with 
v1.4.6-9-gaadd0b65c987 which is much more recent than the license change 
in 2007, so this seems fine to me.

Additionally, I believe the mistake originates from 
35084760a9f492f29434020b64f1db339bf99a23 which forgets to add the OR in 
the SPDX license identifier while the verbatim license language clearly 
states it can be used under the terms of one or the other license.

It would be better to have Masahiro Yamada (added in Cc) confirm that it 
is indeed the intended license since they added the code back in 2018, 
c.f. commit ae9ace7089d2167cbf8a69a29705049ae11c8eea, but this seems 
correct to me.

Please fix the typo and add a bit of context to the commit log as to why 
this is a valid license change (because it actually is) considering the 
code doesn't actually come from the dtc source repo so doesn't *have* to 
follow the license from the original libfdt_rw.c implementation.

Cheers,
Quentin