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Chris Zankel9a8fd552005-06-23 22:01:26 -07001/*
2 * include/asm-xtensa/bitops.h
3 *
4 * Atomic operations that C can't guarantee us.Useful for resource counting etc.
5 *
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License. See the file "COPYING" in the main directory of this archive
8 * for more details.
9 *
Chris Zankelef6051a2007-05-31 17:41:14 -070010 * Copyright (C) 2001 - 2007 Tensilica Inc.
Chris Zankel9a8fd552005-06-23 22:01:26 -070011 */
12
13#ifndef _XTENSA_BITOPS_H
14#define _XTENSA_BITOPS_H
15
16#ifdef __KERNEL__
17
18#include <asm/processor.h>
19#include <asm/byteorder.h>
20#include <asm/system.h>
21
22#ifdef CONFIG_SMP
23# error SMP not supported on this architecture
24#endif
25
Chris Zankel9a8fd552005-06-23 22:01:26 -070026#define smp_mb__before_clear_bit() barrier()
27#define smp_mb__after_clear_bit() barrier()
28
Akinobu Mitad4337aa2006-03-26 01:39:43 -080029#include <asm-generic/bitops/atomic.h>
30#include <asm-generic/bitops/non-atomic.h>
Chris Zankel9a8fd552005-06-23 22:01:26 -070031
Chris Zankel288a60c2005-09-22 21:44:23 -070032#if XCHAL_HAVE_NSA
Chris Zankel9a8fd552005-06-23 22:01:26 -070033
Chris Zankelef6051a2007-05-31 17:41:14 -070034static inline unsigned long __cntlz (unsigned long x)
Chris Zankel9a8fd552005-06-23 22:01:26 -070035{
36 int lz;
37 asm ("nsau %0, %1" : "=r" (lz) : "r" (x));
Chris Zankelef6051a2007-05-31 17:41:14 -070038 return lz;
Chris Zankel9a8fd552005-06-23 22:01:26 -070039}
40
Chris Zankel9a8fd552005-06-23 22:01:26 -070041/*
42 * ffz: Find first zero in word. Undefined if no zero exists.
43 * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
44 */
45
Chris Zankelef6051a2007-05-31 17:41:14 -070046static inline int ffz(unsigned long x)
Chris Zankel9a8fd552005-06-23 22:01:26 -070047{
Chris Zankelef6051a2007-05-31 17:41:14 -070048 return 31 - __cntlz(~x & -~x);
Chris Zankel9a8fd552005-06-23 22:01:26 -070049}
50
51/*
52 * __ffs: Find first bit set in word. Return 0 for bit 0
53 */
54
Chris Zankelef6051a2007-05-31 17:41:14 -070055static inline int __ffs(unsigned long x)
Chris Zankel9a8fd552005-06-23 22:01:26 -070056{
Chris Zankelef6051a2007-05-31 17:41:14 -070057 return 31 - __cntlz(x & -x);
Chris Zankel9a8fd552005-06-23 22:01:26 -070058}
59
60/*
61 * ffs: Find first bit set in word. This is defined the same way as
62 * the libc and compiler builtin ffs routines, therefore
63 * differs in spirit from the above ffz (man ffs).
64 */
65
Chris Zankelef6051a2007-05-31 17:41:14 -070066static inline int ffs(unsigned long x)
Chris Zankel9a8fd552005-06-23 22:01:26 -070067{
Chris Zankelef6051a2007-05-31 17:41:14 -070068 return 32 - __cntlz(x & -x);
Chris Zankel9a8fd552005-06-23 22:01:26 -070069}
70
71/*
72 * fls: Find last (most-significant) bit set in word.
73 * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
74 */
75
Chris Zankelef6051a2007-05-31 17:41:14 -070076static inline int fls (unsigned int x)
Chris Zankel9a8fd552005-06-23 22:01:26 -070077{
Chris Zankelef6051a2007-05-31 17:41:14 -070078 return 32 - __cntlz(x);
Chris Zankel9a8fd552005-06-23 22:01:26 -070079}
Chris Zankelef6051a2007-05-31 17:41:14 -070080
81#else
82
83/* Use the generic implementation if we don't have the nsa/nsau instructions. */
84
85# include <asm-generic/bitops/ffs.h>
86# include <asm-generic/bitops/__ffs.h>
87# include <asm-generic/bitops/ffz.h>
88# include <asm-generic/bitops/fls.h>
89
90#endif
91
Akinobu Mitad4337aa2006-03-26 01:39:43 -080092#include <asm-generic/bitops/fls64.h>
93#include <asm-generic/bitops/find.h>
94#include <asm-generic/bitops/ext2-non-atomic.h>
Chris Zankel9a8fd552005-06-23 22:01:26 -070095
96#ifdef __XTENSA_EL__
Chris Zankelde4f6e52007-05-31 17:47:01 -070097# define ext2_set_bit_atomic(lock,nr,addr) \
98 test_and_set_bit((nr), (unsigned long*)(addr))
99# define ext2_clear_bit_atomic(lock,nr,addr) \
100 test_and_clear_bit((nr), (unsigned long*)(addr))
Chris Zankel9a8fd552005-06-23 22:01:26 -0700101#elif defined(__XTENSA_EB__)
Chris Zankelde4f6e52007-05-31 17:47:01 -0700102# define ext2_set_bit_atomic(lock,nr,addr) \
103 test_and_set_bit((nr) ^ 0x18, (unsigned long*)(addr))
104# define ext2_clear_bit_atomic(lock,nr,addr) \
105 test_and_clear_bit((nr) ^ 0x18, (unsigned long*)(addr))
Chris Zankel9a8fd552005-06-23 22:01:26 -0700106#else
107# error processor byte order undefined!
108#endif
109
Akinobu Mitad4337aa2006-03-26 01:39:43 -0800110#include <asm-generic/bitops/hweight.h>
111#include <asm-generic/bitops/sched.h>
112#include <asm-generic/bitops/minix.h>
Chris Zankel9a8fd552005-06-23 22:01:26 -0700113
114#endif /* __KERNEL__ */
115
116#endif /* _XTENSA_BITOPS_H */