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/*
* Copyright (C) 2004-2006 Atmel Corporation
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef __ASM_AVR32_BITOPS_H
#define __ASM_AVR32_BITOPS_H
#ifndef _LINUX_BITOPS_H
#error only <linux/bitops.h> can be included directly
#endif
#include <asm/byteorder.h>
#include <asm/system.h>
/*
* clear_bit() doesn't provide any barrier for the compiler
*/
#define smp_mb__before_clear_bit() barrier()
#define smp_mb__after_clear_bit() barrier()
/*
* set_bit - Atomically set a bit in memory
* @nr: the bit to set
* @addr: the address to start counting from
*
* This function is atomic and may not be reordered. See __set_bit()
* if you do not require the atomic guarantees.
*
* Note that @nr may be almost arbitrarily large; this function is not
* restricted to acting on a single-word quantity.
*/
static inline void set_bit(int nr, volatile void * addr)
{
unsigned long *p = ((unsigned long *)addr) + nr / BITS_PER_LONG;
unsigned long tmp;
if (__builtin_constant_p(nr)) {
asm volatile(
"1: ssrf 5\n"
" ld.w %0, %2\n"
" sbr %0, %3\n"
" stcond %1, %0\n"
" brne 1b"
: "=&r"(tmp), "=o"(*p)
: "m"(*p), "i"(nr)
: "cc");
} else {
unsigned long mask = 1UL << (nr % BITS_PER_LONG);
asm volatile(
"1: ssrf 5\n"
" ld.w %0, %2\n"
" or %0, %3\n"
" stcond %1, %0\n"
" brne 1b"
: "=&r"(tmp), "=o"(*p)
: "m"(*p), "r"(mask)
: "cc");
}
}
/*
* clear_bit - Clears a bit in memory
* @nr: Bit to clear
* @addr: Address to start counting from
*
* clear_bit() is atomic and may not be reordered. However, it does
* not contain a memory barrier, so if it is used for locking purposes,
* you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit()
* in order to ensure changes are visible on other processors.
*/
static inline void clear_bit(int nr, volatile void * addr)
{
unsigned long *p = ((unsigned long *)addr) + nr / BITS_PER_LONG;
unsigned long tmp;
if (__builtin_constant_p(nr)) {
asm volatile(
"1: ssrf 5\n"
" ld.w %0, %2\n"
" cbr %0, %3\n"
" stcond %1, %0\n"
" brne 1b"
: "=&r"(tmp), "=o"(*p)
: "m"(*p), "i"(nr)
: "cc");
} else {
unsigned long mask = 1UL << (nr % BITS_PER_LONG);
asm volatile(
"1: ssrf 5\n"
" ld.w %0, %2\n"
" andn %0, %3\n"
" stcond %1, %0\n"
" brne 1b"
: "=&r"(tmp), "=o"(*p)
: "m"(*p), "r"(mask)
: "cc");
}
}
/*
* change_bit - Toggle a bit in memory
* @nr: Bit to change
* @addr: Address to start counting from
*
* change_bit() is atomic and may not be reordered.
* Note that @nr may be almost arbitrarily large; this function is not
* restricted to acting on a single-word quantity.
*/
static inline void change_bit(int nr, volatile void * addr)
{
unsigned long *p = ((unsigned long *)addr) + nr / BITS_PER_LONG;
unsigned long mask = 1UL << (nr % BITS_PER_LONG);
unsigned long tmp;
asm volatile(
"1: ssrf 5\n"
" ld.w %0, %2\n"
" eor %0, %3\n"
" stcond %1, %0\n"
" brne 1b"
: "=&r"(tmp), "=o"(*p)
: "m"(*p), "r"(mask)
: "cc");
}
/*
* test_and_set_bit - Set a bit and return its old value
* @nr: Bit to set
* @addr: Address to count from
*
* This operation is atomic and cannot be reordered.
* It also implies a memory barrier.
*/
static inline int test_and_set_bit(int nr, volatile void * addr)
{
unsigned long *p = ((unsigned long *)addr) + nr / BITS_PER_LONG;
unsigned long mask = 1UL << (nr % BITS_PER_LONG);
unsigned long tmp, old;
if (__builtin_constant_p(nr)) {
asm volatile(
"1: ssrf 5\n"
" ld.w %0, %3\n"
" mov %2, %0\n"
" sbr %0, %4\n"
" stcond %1, %0\n"
" brne 1b"
: "=&r"(tmp), "=o"(*p), "=&r"(old)
: "m"(*p), "i"(nr)
: "memory", "cc");
} else {
asm volatile(
"1: ssrf 5\n"
" ld.w %2, %3\n"
" or %0, %2, %4\n"
" stcond %1, %0\n"
" brne 1b"
: "=&r"(tmp), "=o"(*p), "=&r"(old)
: "m"(*p), "r"(mask)
: "memory", "cc");
}
return (old & mask) != 0;
}
/*
* test_and_clear_bit - Clear a bit and return its old value
* @nr: Bit to clear
* @addr: Address to count from
*
* This operation is atomic and cannot be reordered.
* It also implies a memory barrier.
*/
static inline int test_and_clear_bit(int nr, volatile void * addr)
{
unsigned long *p = ((unsigned long *)addr) + nr / BITS_PER_LONG;
unsigned long mask = 1UL << (nr % BITS_PER_LONG);
unsigned long tmp, old;
if (__builtin_constant_p(nr)) {
asm volatile(
"1: ssrf 5\n"
" ld.w %0, %3\n"
" mov %2, %0\n"
" cbr %0, %4\n"
" stcond %1, %0\n"
" brne 1b"
: "=&r"(tmp), "=o"(*p), "=&r"(old)
: "m"(*p), "i"(nr)
: "memory", "cc");
} else {
asm volatile(
"1: ssrf 5\n"
" ld.w %0, %3\n"
" mov %2, %0\n"
" andn %0, %4\n"
" stcond %1, %0\n"
" brne 1b"
: "=&r"(tmp), "=o"(*p), "=&r"(old)
: "m"(*p), "r"(mask)
: "memory", "cc");
}
return (old & mask) != 0;
}
/*
* test_and_change_bit - Change a bit and return its old value
* @nr: Bit to change
* @addr: Address to count from
*
* This operation is atomic and cannot be reordered.
* It also implies a memory barrier.
*/
static inline int test_and_change_bit(int nr, volatile void * addr)
{
unsigned long *p = ((unsigned long *)addr) + nr / BITS_PER_LONG;
unsigned long mask = 1UL << (nr % BITS_PER_LONG);
unsigned long tmp, old;
asm volatile(
"1: ssrf 5\n"
" ld.w %2, %3\n"
" eor %0, %2, %4\n"
" stcond %1, %0\n"
" brne 1b"
: "=&r"(tmp), "=o"(*p), "=&r"(old)
: "m"(*p), "r"(mask)
: "memory", "cc");
return (old & mask) != 0;
}
#include <asm-generic/bitops/non-atomic.h>
/* Find First bit Set */
static inline unsigned long __ffs(unsigned long word)
{
unsigned long result;
asm("brev %1\n\t"
"clz %0,%1"
: "=r"(result), "=&r"(word)
: "1"(word));
return result;
}
/* Find First Zero */
static inline unsigned long ffz(unsigned long word)
{
return __ffs(~word);
}
/* Find Last bit Set */
static inline int fls(unsigned long word)
{
unsigned long result;
asm("clz %0,%1" : "=r"(result) : "r"(word));
return 32 - result;
}
unsigned long find_first_zero_bit(const unsigned long *addr,
unsigned long size);
unsigned long find_next_zero_bit(const unsigned long *addr,
unsigned long size,
unsigned long offset);
unsigned long find_first_bit(const unsigned long *addr,
unsigned long size);
unsigned long find_next_bit(const unsigned long *addr,
unsigned long size,
unsigned long offset);
/*
* ffs: find first bit set. This is defined the same way as
* the libc and compiler builtin ffs routines, therefore
* differs in spirit from the above ffz (man ffs).
*
* The difference is that bit numbering starts at 1, and if no bit is set,
* the function returns 0.
*/
static inline int ffs(unsigned long word)
{
if(word == 0)
return 0;
return __ffs(word) + 1;
}
#include <asm-generic/bitops/fls64.h>
#include <asm-generic/bitops/sched.h>
#include <asm-generic/bitops/hweight.h>
#include <asm-generic/bitops/lock.h>
#include <asm-generic/bitops/ext2-non-atomic.h>
#include <asm-generic/bitops/ext2-atomic.h>
#include <asm-generic/bitops/minix-le.h>
#endif /* __ASM_AVR32_BITOPS_H */
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