mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-11 13:04:03 +08:00
e2be04c7f9
Many user space API headers have licensing information, which is either
incomplete, badly formatted or just a shorthand for referring to the
license under which the file is supposed to be. This makes it hard for
compliance tools to determine the correct license.
Update these files with an SPDX license identifier. The identifier was
chosen based on the license information in the file.
GPL/LGPL licensed headers get the matching GPL/LGPL SPDX license
identifier with the added 'WITH Linux-syscall-note' exception, which is
the officially assigned exception identifier for the kernel syscall
exception:
NOTE! This copyright does *not* cover user programs that use kernel
services by normal system calls - this is merely considered normal use
of the kernel, and does *not* fall under the heading of "derived work".
This exception makes it possible to include GPL headers into non GPL
code, without confusing license compliance tools.
Headers which have either explicit dual licensing or are just licensed
under a non GPL license are updated with the corresponding SPDX
identifier and the GPLv2 with syscall exception identifier. The format
is:
((GPL-2.0 WITH Linux-syscall-note) OR SPDX-ID-OF-OTHER-LICENSE)
SPDX license identifiers are a legally binding shorthand, which can be
used instead of the full boiler plate text. The update does not remove
existing license information as this has to be done on a case by case
basis and the copyright holders might have to be consulted. This will
happen in a separate step.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne. See the previous patch in this series for the
methodology of how this patch was researched.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
72 lines
2.1 KiB
C
72 lines
2.1 KiB
C
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
|
|
/*
|
|
* include/asm-xtensa/swab.h
|
|
*
|
|
* This file is subject to the terms and conditions of the GNU General Public
|
|
* License. See the file "COPYING" in the main directory of this archive
|
|
* for more details.
|
|
*
|
|
* Copyright (C) 2001 - 2005 Tensilica Inc.
|
|
*/
|
|
|
|
#ifndef _XTENSA_SWAB_H
|
|
#define _XTENSA_SWAB_H
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/compiler.h>
|
|
|
|
#define __SWAB_64_THRU_32__
|
|
|
|
static inline __attribute_const__ __u32 __arch_swab32(__u32 x)
|
|
{
|
|
__u32 res;
|
|
/* instruction sequence from Xtensa ISA release 2/2000 */
|
|
__asm__("ssai 8 \n\t"
|
|
"srli %0, %1, 16 \n\t"
|
|
"src %0, %0, %1 \n\t"
|
|
"src %0, %0, %0 \n\t"
|
|
"src %0, %1, %0 \n"
|
|
: "=&a" (res)
|
|
: "a" (x)
|
|
);
|
|
return res;
|
|
}
|
|
#define __arch_swab32 __arch_swab32
|
|
|
|
static inline __attribute_const__ __u16 __arch_swab16(__u16 x)
|
|
{
|
|
/* Given that 'short' values are signed (i.e., can be negative),
|
|
* we cannot assume that the upper 16-bits of the register are
|
|
* zero. We are careful to mask values after shifting.
|
|
*/
|
|
|
|
/* There exists an anomaly between xt-gcc and xt-xcc. xt-gcc
|
|
* inserts an extui instruction after putting this function inline
|
|
* to ensure that it uses only the least-significant 16 bits of
|
|
* the result. xt-xcc doesn't use an extui, but assumes the
|
|
* __asm__ macro follows convention that the upper 16 bits of an
|
|
* 'unsigned short' result are still zero. This macro doesn't
|
|
* follow convention; indeed, it leaves garbage in the upport 16
|
|
* bits of the register.
|
|
|
|
* Declaring the temporary variables 'res' and 'tmp' to be 32-bit
|
|
* types while the return type of the function is a 16-bit type
|
|
* forces both compilers to insert exactly one extui instruction
|
|
* (or equivalent) to mask off the upper 16 bits. */
|
|
|
|
__u32 res;
|
|
__u32 tmp;
|
|
|
|
__asm__("extui %1, %2, 8, 8\n\t"
|
|
"slli %0, %2, 8 \n\t"
|
|
"or %0, %0, %1 \n"
|
|
: "=&a" (res), "=&a" (tmp)
|
|
: "a" (x)
|
|
);
|
|
|
|
return res;
|
|
}
|
|
#define __arch_swab16 __arch_swab16
|
|
|
|
#endif /* _XTENSA_SWAB_H */
|