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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
Jiri Slaby06245172007-10-18 23:40:26 -070018#ifndef _LINUX_BITOPS_H
19#error only <linux/bitops.h> can be included directly
20#endif
21
Chris Zankel9a8fd552005-06-23 22:01:26 -070022#include <asm/processor.h>
23#include <asm/byteorder.h>
24#include <asm/system.h>
25
26#ifdef CONFIG_SMP
27# error SMP not supported on this architecture
28#endif
29
Chris Zankel9a8fd552005-06-23 22:01:26 -070030#define smp_mb__before_clear_bit() barrier()
31#define smp_mb__after_clear_bit() barrier()
32
Akinobu Mitad4337aa2006-03-26 01:39:43 -080033#include <asm-generic/bitops/atomic.h>
34#include <asm-generic/bitops/non-atomic.h>
Chris Zankel9a8fd552005-06-23 22:01:26 -070035
Chris Zankel288a60c2005-09-22 21:44:23 -070036#if XCHAL_HAVE_NSA
Chris Zankel9a8fd552005-06-23 22:01:26 -070037
Chris Zankelef6051a2007-05-31 17:41:14 -070038static inline unsigned long __cntlz (unsigned long x)
Chris Zankel9a8fd552005-06-23 22:01:26 -070039{
40 int lz;
41 asm ("nsau %0, %1" : "=r" (lz) : "r" (x));
Chris Zankelef6051a2007-05-31 17:41:14 -070042 return lz;
Chris Zankel9a8fd552005-06-23 22:01:26 -070043}
44
Chris Zankel9a8fd552005-06-23 22:01:26 -070045/*
46 * ffz: Find first zero in word. Undefined if no zero exists.
47 * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
48 */
49
Chris Zankelef6051a2007-05-31 17:41:14 -070050static inline int ffz(unsigned long x)
Chris Zankel9a8fd552005-06-23 22:01:26 -070051{
Chris Zankelef6051a2007-05-31 17:41:14 -070052 return 31 - __cntlz(~x & -~x);
Chris Zankel9a8fd552005-06-23 22:01:26 -070053}
54
55/*
56 * __ffs: Find first bit set in word. Return 0 for bit 0
57 */
58
Chris Zankelef6051a2007-05-31 17:41:14 -070059static inline int __ffs(unsigned long x)
Chris Zankel9a8fd552005-06-23 22:01:26 -070060{
Chris Zankelef6051a2007-05-31 17:41:14 -070061 return 31 - __cntlz(x & -x);
Chris Zankel9a8fd552005-06-23 22:01:26 -070062}
63
64/*
65 * ffs: Find first bit set in word. This is defined the same way as
66 * the libc and compiler builtin ffs routines, therefore
67 * differs in spirit from the above ffz (man ffs).
68 */
69
Chris Zankelef6051a2007-05-31 17:41:14 -070070static inline int ffs(unsigned long x)
Chris Zankel9a8fd552005-06-23 22:01:26 -070071{
Chris Zankelef6051a2007-05-31 17:41:14 -070072 return 32 - __cntlz(x & -x);
Chris Zankel9a8fd552005-06-23 22:01:26 -070073}
74
75/*
76 * fls: Find last (most-significant) bit set in word.
77 * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
78 */
79
Chris Zankelef6051a2007-05-31 17:41:14 -070080static inline int fls (unsigned int x)
Chris Zankel9a8fd552005-06-23 22:01:26 -070081{
Chris Zankelef6051a2007-05-31 17:41:14 -070082 return 32 - __cntlz(x);
Chris Zankel9a8fd552005-06-23 22:01:26 -070083}
Chris Zankelef6051a2007-05-31 17:41:14 -070084
Rusty Russell5ece5c52009-01-03 16:21:08 +103085/**
86 * __fls - find last (most-significant) set bit in a long word
87 * @word: the word to search
88 *
89 * Undefined if no set bit exists, so code should check against 0 first.
90 */
91static inline unsigned long __fls(unsigned long word)
92{
93 return 31 - __cntlz(word);
94}
Chris Zankelef6051a2007-05-31 17:41:14 -070095#else
96
97/* Use the generic implementation if we don't have the nsa/nsau instructions. */
98
99# include <asm-generic/bitops/ffs.h>
100# include <asm-generic/bitops/__ffs.h>
101# include <asm-generic/bitops/ffz.h>
102# include <asm-generic/bitops/fls.h>
Rusty Russell5ece5c52009-01-03 16:21:08 +1030103# include <asm-generic/bitops/__fls.h>
Chris Zankelef6051a2007-05-31 17:41:14 -0700104
105#endif
106
Akinobu Mitad4337aa2006-03-26 01:39:43 -0800107#include <asm-generic/bitops/fls64.h>
108#include <asm-generic/bitops/find.h>
Akinobu Mita861b5ae2011-03-23 16:42:02 -0700109#include <asm-generic/bitops/le.h>
Chris Zankel9a8fd552005-06-23 22:01:26 -0700110
111#ifdef __XTENSA_EL__
Chris Zankelde4f6e52007-05-31 17:47:01 -0700112# define ext2_set_bit_atomic(lock,nr,addr) \
113 test_and_set_bit((nr), (unsigned long*)(addr))
114# define ext2_clear_bit_atomic(lock,nr,addr) \
115 test_and_clear_bit((nr), (unsigned long*)(addr))
Chris Zankel9a8fd552005-06-23 22:01:26 -0700116#elif defined(__XTENSA_EB__)
Chris Zankelde4f6e52007-05-31 17:47:01 -0700117# define ext2_set_bit_atomic(lock,nr,addr) \
118 test_and_set_bit((nr) ^ 0x18, (unsigned long*)(addr))
119# define ext2_clear_bit_atomic(lock,nr,addr) \
120 test_and_clear_bit((nr) ^ 0x18, (unsigned long*)(addr))
Chris Zankel9a8fd552005-06-23 22:01:26 -0700121#else
122# error processor byte order undefined!
123#endif
124
Akinobu Mitad4337aa2006-03-26 01:39:43 -0800125#include <asm-generic/bitops/hweight.h>
Nick Piggin26333572007-10-18 03:06:39 -0700126#include <asm-generic/bitops/lock.h>
Akinobu Mitad4337aa2006-03-26 01:39:43 -0800127#include <asm-generic/bitops/sched.h>
Chris Zankel9a8fd552005-06-23 22:01:26 -0700128
129#endif /* __KERNEL__ */
130
131#endif /* _XTENSA_BITOPS_H */