1/*
  2 * Copyright 2011 Tilera Corporation. All Rights Reserved.
  3 *
  4 *   This program is free software; you can redistribute it and/or
  5 *   modify it under the terms of the GNU General Public License
  6 *   as published by the Free Software Foundation, version 2.
  7 *
  8 *   This program is distributed in the hope that it will be useful, but
  9 *   WITHOUT ANY WARRANTY; without even the implied warranty of
 10 *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
 11 *   NON INFRINGEMENT.  See the GNU General Public License for
 12 *   more details.
 13 */
 14
 15#ifndef _ASM_TILE_BITOPS_64_H
 16#define _ASM_TILE_BITOPS_64_H
 17
 18#include <linux/compiler.h>
 19#include <linux/atomic.h>
 20#include <asm/system.h>
 21
 22/* See <asm/bitops.h> for API comments. */
 23
 24static inline void set_bit(unsigned nr, volatile unsigned long *addr)
 25{
 26	unsigned long mask = (1UL << (nr % BITS_PER_LONG));
 27	__insn_fetchor((void *)(addr + nr / BITS_PER_LONG), mask);
 28}
 29
 30static inline void clear_bit(unsigned nr, volatile unsigned long *addr)
 31{
 32	unsigned long mask = (1UL << (nr % BITS_PER_LONG));
 33	__insn_fetchand((void *)(addr + nr / BITS_PER_LONG), ~mask);
 34}
 35
 36#define smp_mb__before_clear_bit()	smp_mb()
 37#define smp_mb__after_clear_bit()	smp_mb()
 38
 39
 40static inline void change_bit(unsigned nr, volatile unsigned long *addr)
 41{
 42	unsigned long old, mask = (1UL << (nr % BITS_PER_LONG));
 43	long guess, oldval;
 44	addr += nr / BITS_PER_LONG;
 45	old = *addr;
 46	do {
 47		guess = oldval;
 48		oldval = atomic64_cmpxchg((atomic64_t *)addr,
 49					  guess, guess ^ mask);
 50	} while (guess != oldval);
 51}
 52
 53
 54/*
 55 * The test_and_xxx_bit() routines require a memory fence before we
 56 * start the operation, and after the operation completes.  We use
 57 * smp_mb() before, and rely on the "!= 0" comparison, plus a compiler
 58 * barrier(), to block until the atomic op is complete.
 59 */
 60
 61static inline int test_and_set_bit(unsigned nr, volatile unsigned long *addr)
 62{
 63	int val;
 64	unsigned long mask = (1UL << (nr % BITS_PER_LONG));
 65	smp_mb();  /* barrier for proper semantics */
 66	val = (__insn_fetchor((void *)(addr + nr / BITS_PER_LONG), mask)
 67	       & mask) != 0;
 68	barrier();
 69	return val;
 70}
 71
 72
 73static inline int test_and_clear_bit(unsigned nr, volatile unsigned long *addr)
 74{
 75	int val;
 76	unsigned long mask = (1UL << (nr % BITS_PER_LONG));
 77	smp_mb();  /* barrier for proper semantics */
 78	val = (__insn_fetchand((void *)(addr + nr / BITS_PER_LONG), ~mask)
 79	       & mask) != 0;
 80	barrier();
 81	return val;
 82}
 83
 84
 85static inline int test_and_change_bit(unsigned nr,
 86				      volatile unsigned long *addr)
 87{
 88	unsigned long mask = (1UL << (nr % BITS_PER_LONG));
 89	long guess, oldval = *addr;
 90	addr += nr / BITS_PER_LONG;
 91	oldval = *addr;
 92	do {
 93		guess = oldval;
 94		oldval = atomic64_cmpxchg((atomic64_t *)addr,
 95					  guess, guess ^ mask);
 96	} while (guess != oldval);
 97	return (oldval & mask) != 0;
 98}
 99
100#include <asm-generic/bitops/ext2-atomic-setbit.h>
101
102#endif /* _ASM_TILE_BITOPS_64_H */