mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-16 08:44:21 +08:00
0624517d80
forbid asm/bitops.h direct inclusion Because of compile errors that may occur after bit changes if asm/bitops.h is included directly without e.g. linux/kernel.h which includes linux/bitops.h, forbid direct inclusion of asm/bitops.h. Thanks to Adrian Bunk. Signed-off-by: Jiri Slaby <jirislaby@gmail.com> Cc: Adrian Bunk <bunk@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
122 lines
2.8 KiB
C
122 lines
2.8 KiB
C
/*
|
|
* include/asm-xtensa/bitops.h
|
|
*
|
|
* Atomic operations that C can't guarantee us.Useful for resource counting etc.
|
|
*
|
|
* 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 - 2007 Tensilica Inc.
|
|
*/
|
|
|
|
#ifndef _XTENSA_BITOPS_H
|
|
#define _XTENSA_BITOPS_H
|
|
|
|
#ifdef __KERNEL__
|
|
|
|
#ifndef _LINUX_BITOPS_H
|
|
#error only <linux/bitops.h> can be included directly
|
|
#endif
|
|
|
|
#include <asm/processor.h>
|
|
#include <asm/byteorder.h>
|
|
#include <asm/system.h>
|
|
|
|
#ifdef CONFIG_SMP
|
|
# error SMP not supported on this architecture
|
|
#endif
|
|
|
|
#define smp_mb__before_clear_bit() barrier()
|
|
#define smp_mb__after_clear_bit() barrier()
|
|
|
|
#include <asm-generic/bitops/atomic.h>
|
|
#include <asm-generic/bitops/non-atomic.h>
|
|
|
|
#if XCHAL_HAVE_NSA
|
|
|
|
static inline unsigned long __cntlz (unsigned long x)
|
|
{
|
|
int lz;
|
|
asm ("nsau %0, %1" : "=r" (lz) : "r" (x));
|
|
return lz;
|
|
}
|
|
|
|
/*
|
|
* ffz: Find first zero in word. Undefined if no zero exists.
|
|
* bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
|
|
*/
|
|
|
|
static inline int ffz(unsigned long x)
|
|
{
|
|
return 31 - __cntlz(~x & -~x);
|
|
}
|
|
|
|
/*
|
|
* __ffs: Find first bit set in word. Return 0 for bit 0
|
|
*/
|
|
|
|
static inline int __ffs(unsigned long x)
|
|
{
|
|
return 31 - __cntlz(x & -x);
|
|
}
|
|
|
|
/*
|
|
* ffs: Find first bit set in word. This is defined the same way as
|
|
* the libc and compiler builtin ffs routines, therefore
|
|
* differs in spirit from the above ffz (man ffs).
|
|
*/
|
|
|
|
static inline int ffs(unsigned long x)
|
|
{
|
|
return 32 - __cntlz(x & -x);
|
|
}
|
|
|
|
/*
|
|
* fls: Find last (most-significant) bit set in word.
|
|
* Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
|
|
*/
|
|
|
|
static inline int fls (unsigned int x)
|
|
{
|
|
return 32 - __cntlz(x);
|
|
}
|
|
|
|
#else
|
|
|
|
/* Use the generic implementation if we don't have the nsa/nsau instructions. */
|
|
|
|
# include <asm-generic/bitops/ffs.h>
|
|
# include <asm-generic/bitops/__ffs.h>
|
|
# include <asm-generic/bitops/ffz.h>
|
|
# include <asm-generic/bitops/fls.h>
|
|
|
|
#endif
|
|
|
|
#include <asm-generic/bitops/fls64.h>
|
|
#include <asm-generic/bitops/find.h>
|
|
#include <asm-generic/bitops/ext2-non-atomic.h>
|
|
|
|
#ifdef __XTENSA_EL__
|
|
# define ext2_set_bit_atomic(lock,nr,addr) \
|
|
test_and_set_bit((nr), (unsigned long*)(addr))
|
|
# define ext2_clear_bit_atomic(lock,nr,addr) \
|
|
test_and_clear_bit((nr), (unsigned long*)(addr))
|
|
#elif defined(__XTENSA_EB__)
|
|
# define ext2_set_bit_atomic(lock,nr,addr) \
|
|
test_and_set_bit((nr) ^ 0x18, (unsigned long*)(addr))
|
|
# define ext2_clear_bit_atomic(lock,nr,addr) \
|
|
test_and_clear_bit((nr) ^ 0x18, (unsigned long*)(addr))
|
|
#else
|
|
# error processor byte order undefined!
|
|
#endif
|
|
|
|
#include <asm-generic/bitops/hweight.h>
|
|
#include <asm-generic/bitops/lock.h>
|
|
#include <asm-generic/bitops/sched.h>
|
|
#include <asm-generic/bitops/minix.h>
|
|
|
|
#endif /* __KERNEL__ */
|
|
|
|
#endif /* _XTENSA_BITOPS_H */
|