bitops.h

  1/* SPDX-License-Identifier: GPL-2.0-only */
  2/*
  3 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
  4 */
  5
  6#ifndef _ASM_BITOPS_H
  7#define _ASM_BITOPS_H
  8
  9#ifndef _LINUX_BITOPS_H
 10#error only <linux/bitops.h> can be included directly
 11#endif
 12
 13#ifndef __ASSEMBLER__
 14
 15#include <linux/types.h>
 16#include <linux/compiler.h>
 17
 18#ifdef CONFIG_ISA_ARCOMPACT
 19
 20/*
 21 * Count the number of zeros, starting from MSB
 22 * Helper for fls( ) friends
 23 * This is a pure count, so (1-32) or (0-31) doesn't apply
 24 * It could be 0 to 32, based on num of 0's in there
 25 * clz(0x8000_0000) = 0, clz(0xFFFF_FFFF)=0, clz(0) = 32, clz(1) = 31
 26 */
 27static inline __attribute__ ((const)) int clz(unsigned int x)
 28{
 29	unsigned int res;
 30
 31	__asm__ __volatile__(
 32	"	norm.f  %0, %1		\n"
 33	"	mov.n   %0, 0		\n"
 34	"	add.p   %0, %0, 1	\n"
 35	: "=r"(res)
 36	: "r"(x)
 37	: "cc");
 38
 39	return res;
 40}
 41
 42static inline int constant_fls(unsigned int x)
 43{
 44	int r = 32;
 45
 46	if (!x)
 47		return 0;
 48	if (!(x & 0xffff0000u)) {
 49		x <<= 16;
 50		r -= 16;
 51	}
 52	if (!(x & 0xff000000u)) {
 53		x <<= 8;
 54		r -= 8;
 55	}
 56	if (!(x & 0xf0000000u)) {
 57		x <<= 4;
 58		r -= 4;
 59	}
 60	if (!(x & 0xc0000000u)) {
 61		x <<= 2;
 62		r -= 2;
 63	}
 64	if (!(x & 0x80000000u))
 65		r -= 1;
 66	return r;
 67}
 68
 69/*
 70 * fls = Find Last Set in word
 71 * @result: [1-32]
 72 * fls(1) = 1, fls(0x80000000) = 32, fls(0) = 0
 73 */
 74static inline __attribute__ ((const)) int fls(unsigned int x)
 75{
 76	if (__builtin_constant_p(x))
 77	       return constant_fls(x);
 78
 79	return 32 - clz(x);
 80}
 81
 82/*
 83 * __fls: Similar to fls, but zero based (0-31)
 84 */
 85static inline __attribute__ ((const)) unsigned long __fls(unsigned long x)
 86{
 87	if (!x)
 88		return 0;
 89	else
 90		return fls(x) - 1;
 91}
 92
 93/*
 94 * ffs = Find First Set in word (LSB to MSB)
 95 * @result: [1-32], 0 if all 0's
 96 */
 97#define ffs(x)	({ unsigned long __t = (x); fls(__t & -__t); })
 98
 99/*
100 * __ffs: Similar to ffs, but zero based (0-31)
101 */
102static inline __attribute__ ((const)) unsigned long __ffs(unsigned long word)
103{
104	if (!word)
105		return word;
106
107	return ffs(word) - 1;
108}
109
110#else	/* CONFIG_ISA_ARCV2 */
111
112/*
113 * fls = Find Last Set in word
114 * @result: [1-32]
115 * fls(1) = 1, fls(0x80000000) = 32, fls(0) = 0
116 */
117static inline __attribute__ ((const)) int fls(unsigned int x)
118{
119	int n;
120
121	asm volatile(
122	"	fls.f	%0, %1		\n"  /* 0:31; 0(Z) if src 0 */
123	"	add.nz	%0, %0, 1	\n"  /* 0:31 -> 1:32 */
124	: "=r"(n)	/* Early clobber not needed */
125	: "r"(x)
126	: "cc");
127
128	return n;
129}
130
131/*
132 * __fls: Similar to fls, but zero based (0-31). Also 0 if no bit set
133 */
134static inline __attribute__ ((const)) unsigned long __fls(unsigned long x)
135{
136	if (__builtin_constant_p(x))
137		return x ? BITS_PER_LONG - 1 - __builtin_clzl(x) : 0;
138	/* FLS insn has exactly same semantics as the API */
139	return	__builtin_arc_fls(x);
140}
141
142/*
143 * ffs = Find First Set in word (LSB to MSB)
144 * @result: [1-32], 0 if all 0's
145 */
146static inline __attribute__ ((const)) int ffs(unsigned int x)
147{
148	int n;
149
150	asm volatile(
151	"	ffs.f	%0, %1		\n"  /* 0:31; 31(Z) if src 0 */
152	"	add.nz	%0, %0, 1	\n"  /* 0:31 -> 1:32 */
153	"	mov.z	%0, 0		\n"  /* 31(Z)-> 0 */
154	: "=r"(n)	/* Early clobber not needed */
155	: "r"(x)
156	: "cc");
157
158	return n;
159}
160
161/*
162 * __ffs: Similar to ffs, but zero based (0-31)
163 */
164static inline __attribute__ ((const)) unsigned long __ffs(unsigned long x)
165{
166	unsigned long n;
167
168	asm volatile(
169	"	ffs.f	%0, %1		\n"  /* 0:31; 31(Z) if src 0 */
170	"	mov.z	%0, 0		\n"  /* 31(Z)-> 0 */
171	: "=r"(n)
172	: "r"(x)
173	: "cc");
174
175	return n;
176
177}
178
179#endif	/* CONFIG_ISA_ARCOMPACT */
180
181/*
182 * ffz = Find First Zero in word.
183 * @return:[0-31], 32 if all 1's
184 */
185#define ffz(x)	__ffs(~(x))
186
187#include <asm-generic/bitops/hweight.h>
188#include <asm-generic/bitops/fls64.h>
189#include <asm-generic/bitops/sched.h>
190#include <asm-generic/bitops/lock.h>
191#include <asm-generic/bitops/atomic.h>
192#include <asm-generic/bitops/non-atomic.h>
193
194#include <asm-generic/bitops/le.h>
195#include <asm-generic/bitops/ext2-atomic-setbit.h>
196
197#endif /* !__ASSEMBLER__ */
198
199#endif