+SPDX-License-Identifier: GPL-2.0
+
U-Boot is Free Software. It is copyrighted by Wolfgang Denk and
many others who contributed code (see the actual source code and the
git commit messages for details). You can redistribute U-Boot and/or
To make this easier, such license headers in the source files will be
replaced with a single line reference to Unique License Identifiers
-as defined by the Linux Foundation's SPDX project [1]. For example,
-in a source file the full "GPL v2.0 or later" header text will be
-replaced by a single line:
+as defined by the Linux Foundation's SPDX project [1].
+
+If a "SPDX-License-Identifier:" line references more than one Unique
+License Identifier, then this means that the respective file can be
+used under the terms of either of these licenses, i. e. with
- SPDX-License-Identifier: GPL-2.0+
+ SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
+
+you can choose between GPL-2.0+ and BSD-3-Clause licensing.
We use the SPDX Unique License Identifiers here; these are available
at [2].
+License identifier syntax
+-------------------------
+
+1. Placement:
+
+ The SPDX license identifier in U-Boot files shall be added at the first
+ possible line in a file which can contain a comment. For the majority
+ or files this is the first line, except for scripts which require the
+ '#!PATH_TO_INTERPRETER' in the first line. For those scripts the SPDX
+ identifier goes into the second line.
+
+|
+
+2. Style:
+
+ The SPDX license identifier is added in form of a comment. The comment
+ style depends on the file type::
+
+ C source: // SPDX-License-Identifier: <SPDX License Expression>
+ C header: /* SPDX-License-Identifier: <SPDX License Expression> */
+ ASM: /* SPDX-License-Identifier: <SPDX License Expression> */
+ scripts: # SPDX-License-Identifier: <SPDX License Expression>
+ .rst: .. SPDX-License-Identifier: <SPDX License Expression>
+ .dts{i}: // SPDX-License-Identifier: <SPDX License Expression>
+
+ If a specific tool cannot handle the standard comment style, then the
+ appropriate comment mechanism which the tool accepts shall be used. This
+ is the reason for having the "/\* \*/" style comment in C header
+ files. There was build breakage observed with generated .lds files where
+ 'ld' failed to parse the C++ comment. This has been fixed by now, but
+ there are still older assembler tools which cannot handle C++ style
+ comments.
+
+|
+
+3. Syntax:
+
+ A <SPDX License Expression> is either an SPDX short form license
+ identifier found on the SPDX License List, or the combination of two
+ SPDX short form license identifiers separated by "WITH" when a license
+ exception applies. When multiple licenses apply, an expression consists
+ of keywords "AND", "OR" separating sub-expressions and surrounded by
+ "(", ")" .
+
+ License identifiers for licenses like [L]GPL with the 'or later' option
+ are constructed by using a "+" for indicating the 'or later' option.::
+
+ // SPDX-License-Identifier: GPL-2.0+
+ // SPDX-License-Identifier: LGPL-2.1+
+
+ WITH should be used when there is a modifier to a license needed.
+ For example, the linux kernel UAPI files use the expression::
+
+ // SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note
+ // SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note
+
+ Other examples using WITH exceptions found in the linux kernel are::
+
+ // SPDX-License-Identifier: GPL-2.0 WITH mif-exception
+ // SPDX-License-Identifier: GPL-2.0+ WITH GCC-exception-2.0
+
+ Exceptions can only be used with particular License identifiers. The
+ valid License identifiers are listed in the tags of the exception text
+ file.
+
+ OR should be used if the file is dual licensed and only one license is
+ to be selected. For example, some dtsi files are available under dual
+ licenses::
+
+ // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
+
+ Examples from U-Boot for license expressions in dual licensed files::
+
+ // SPDX-License-Identifier: GPL-2.0 OR MIT
+ // SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
+
+ AND should be used if the file has multiple licenses whose terms all
+ apply to use the file. For example, if code is inherited from another
+ project and permission has been given to put it in U-Boot, but the
+ original license terms need to remain in effect::
+
+ // SPDX-License-Identifier: (GPL-2.0 WITH Linux-syscall-note) AND MIT
+
+ Another other example where both sets of license terms need to be
+ adhered to is::
+
+ // SPDX-License-Identifier: GPL-1.0+ AND LGPL-2.1+
+
[1] http://spdx.org/
[2] http://spdx.org/licenses/
-Full name SPDX Identifier OSI Approved File name URI
+Full name SPDX Identifier OSI Approved File name URI
=======================================================================================================================================
-GNU General Public License v2.0 only GPL-2.0 Y gpl-2.0.txt http://www.gnu.org/licenses/gpl-2.0.txt
-GNU General Public License v2.0 or later GPL-2.0+ Y gpl-2.0.txt http://www.gnu.org/licenses/gpl-2.0.txt
-GNU Library General Public License v2 or later LGPL-2.0+ Y lgpl-2.0.txt http://www.gnu.org/licenses/old-licenses/lgpl-2.0.txt
-GNU Lesser General Public License v2.1 or later LGPL-2.1+ Y lgpl-2.1.txt http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt
-eCos license version 2.0 eCos-2.0 eCos-2.0.txt http://www.gnu.org/licenses/ecos-license.html
+GNU General Public License v2.0 only GPL-2.0 Y gpl-2.0.txt http://www.gnu.org/licenses/gpl-2.0.txt
+GNU General Public License v2.0 or later GPL-2.0+ Y gpl-2.0.txt http://www.gnu.org/licenses/gpl-2.0.txt
+GNU Library General Public License v2 or later LGPL-2.0+ Y lgpl-2.0.txt http://www.gnu.org/licenses/old-licenses/lgpl-2.0.txt
+GNU Lesser General Public License v2.1 or later LGPL-2.1+ Y lgpl-2.1.txt http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt
+eCos license version 2.0 eCos-2.0 eCos-2.0.txt http://www.gnu.org/licenses/ecos-license.html
+BSD 2-Clause License BSD-2-Clause Y bsd-2-clause.txt http://spdx.org/licenses/BSD-2-Clause
+BSD 3-clause "New" or "Revised" License BSD-3-Clause Y bsd-3-clause.txt http://spdx.org/licenses/BSD-3-Clause#licenseText
+IBM PIBS (PowerPC Initialization and IBM-pibs ibm-pibs.txt
+ Boot Software) license
+ISC License ISC Y isc.txt https://spdx.org/licenses/ISC
+SIL OPEN FONT LICENSE (OFL-1.1) OFL-1.1 Y OFL.txt https://spdx.org/licenses/OFL-1.1.html
+X11 License X11 x11.txt https://spdx.org/licenses/X11.html
projects / oweals / u-boot.git / blobdiff