/* bitops.h: bit operations for the Fujitsu FR-V CPUs
*
* For an explanation of how atomic ops work in this arch, see:
* Documentation/fujitsu/frv/atomic-ops.txt
*
* Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#ifndef _ASM_BITOPS_H
#define _ASM_BITOPS_H
#include <linux/config.h>
#include <linux/compiler.h>
#include <asm/byteorder.h>
#include <asm/system.h>
#include <asm/atomic.h>
#ifdef __KERNEL__
/*
* ffz = Find First Zero in word. Undefined if no zero exists,
* so code should check against ~0UL first..
*/
static inline unsigned long ffz(unsigned long word)
{
unsigned long result = 0;
while (word & 1) {
result++;
word >>= 1;
}
return result;
}
/*
* clear_bit() doesn't provide any barrier for the compiler.
*/
#define smp_mb__before_clear_bit() barrier()
#define smp_mb__after_clear_bit() barrier()
static inline int test_and_clear_bit(int nr, volatile void *addr)
{
volatile unsigned long *ptr = addr;
unsigned long mask = 1UL << (nr & 31);
ptr += nr >> 5;
return (atomic_test_and_ANDNOT_mask(mask, ptr) & mask) != 0;
}
static inline int test_and_set_bit(int nr, volatile void *addr)
{
volatile unsigned long *ptr = addr;
unsigned long mask = 1UL << (nr & 31);
ptr += nr >> 5;
return (atomic_test_and_OR_mask(mask, ptr) & mask) != 0;
}
static inline int test_and_change_bit(int nr, volatile void *addr)
{
volatile unsigned long *ptr = addr;
unsigned long mask = 1UL << (nr & 31);
ptr += nr >> 5;
return (atomic_test_and_XOR_mask(mask, ptr) & mask) != 0;
}
static inline void clear_bit(int nr, volatile void *addr)
{
test_and_clear_bit(nr, addr);
}
static inline void set_bit(int nr, volatile void *addr)
{
test_and_set_bit(nr, addr);
}
static inline void change_bit(int nr, volatile void * addr)
{
test_and_change_bit(nr, addr);
}
static inline void __clear_bit(int nr, volatile void * addr)
{
volatile unsigned long *a = addr;
int mask;
a += nr >> 5;
mask = 1 << (nr & 31);
*a &= ~mask;
}
static inline void __set_bit(int nr, volatile void * addr)
{
volatile unsigned long *a = addr;
int mask;
a += nr >> 5;
mask = 1 << (nr & 31);
*a |= mask;
}
static inline void __change_bit(int nr, volatile void *addr)
{
volatile unsigned long *a = addr;
int mask;
a += nr >> 5;
mask = 1 << (nr & 31);
*a ^= mask;
}
static inline int __test_and_clear_bit(int nr, volatile void * addr)
{
volatile unsigned long *a = addr;
int mask, retval;
a += nr >> 5;
mask = 1 << (nr & 31);
retval = (mask & *a) != 0;
*a &= ~mask;
return retval;
}
static inline int __test_and_set_bit(int nr, volatile void * addr)
{
volatile unsigned long *a = addr;
int mask, retval;
a += nr >> 5;
mask = 1 << (nr & 31);
retval = (mask & *a) != 0;
*a |= mask;
return retval;
}
static inline int __test_and_change_bit(int nr, volatile void * addr)
{
volatile unsigned long *a = addr;
int mask, retval;
a += nr >> 5;
mask = 1 << (nr & 31);
retval = (mask & *a) != 0;
*a ^= mask;
return retval;
}
/*
* This routine doesn't need to be atomic.
*/
static inline int __constant_test_bit(int nr, const volatile void * addr)
{
return ((1UL << (nr & 31)) & (((const volatile unsigned int *) addr)[nr >> 5])) != 0;
}
static inline int __test_bit(int nr, const volatile void * addr)
{
int * a = (int *) addr;
int mask;
a += nr >> 5;
mask = 1 << (nr & 0x1f);
return ((mask & *a) != 0);
}
#define test_bit(nr,addr) \
(__builtin_constant_p(nr) ? \
__constant_test_bit((nr),(addr)) : \
__test_bit((nr),(addr)))
extern int find_next_bit(const unsigned long *addr, int size, int offset);
#define find_first_bit(addr, size) find_next_bit(addr, size, 0)
#define find_first_zero_bit(addr, size) \
find_next_zero_bit((addr), (size), 0)
static inline int find_next_zero_bit(const void *addr, int size, int offset)
{
const unsigned long *p = ((const unsigned long *) addr) + (offset >> 5);
unsigned long result = offset & ~31UL;
unsigned long tmp;
if (offset >= size)
return size;
size -= result;
offset &= 31UL;
if (offset) {
tmp = *(p++);
tmp |= ~0UL >> (32-offset);
if (size < 32)
goto found_first;
if (~tmp)
goto found_middle;
size -= 32;
result += 32;
}
while (size & ~31UL) {
if (~(tmp = *(p++)))
goto found_middle;
result += 32;
size -= 32;
}
if (!size)
return result;
tmp = *p;
found_first:
tmp |= ~0UL >> size;
found_middle:
return result + ffz(tmp);
}
#define ffs(x) generic_ffs(x)
#define __ffs(x) (ffs(x) - 1)
/*
* fls: find last bit set.
*/
#define fls(x) \
({ \
int bit; \
\
asm("scan %1,gr0,%0" : "=r"(bit) : "r"(x)); \
\
bit ? 33 - bit : bit; \
})
/*
* Every architecture must define this function. It's the fastest
* way of searching a 140-bit bitmap where the first 100 bits are
* unlikely to be set. It's guaranteed that at least one of the 140
* bits is cleared.
*/
static inline int sched_find_first_bit(const unsigned long *b)
{
if (unlikely(b[0]))
return __ffs(b[0]);
if (unlikely(b[1]))
return __ffs(b[1]) + 32;
if (unlikely(b[2]))
return __ffs(b[2]) + 64;
if (b[3])
return __ffs(b[3]) + 96;
return __ffs(b[4]) + 128;
}
/*
* hweightN: returns the hamming weight (i.e. the number
* of bits set) of a N-bit word
*/
#define hweight32(x) generic_hweight32(x)
#define hweight16(x) generic_hweight16(x)
#define hweight8(x) generic_hweight8(x)
#define ext2_set_bit(nr, addr) test_and_set_bit ((nr) ^ 0x18, (addr))
#define ext2_clear_bit(nr, addr) test_and_clear_bit((nr) ^ 0x18, (addr))
#define ext2_set_bit_atomic(lock,nr,addr) ext2_set_bit((nr), addr)
#define ext2_clear_bit_atomic(lock,nr,addr) ext2_clear_bit((nr), addr)
static inline int ext2_test_bit(int nr, const volatile void * addr)
{
const volatile unsigned char *ADDR = (const unsigned char *) addr;
int mask;
ADDR += nr >> 3;
mask = 1 << (nr & 0x07);
return ((mask & *ADDR) != 0);
}
#define ext2_find_first_zero_bit(addr, size) \
ext2_find_next_zero_bit((addr), (size), 0)
static inline unsigned long ext2_find_next_zero_bit(const void *addr,
unsigned long size,
unsigned long offset)
{
const unsigned long *p = ((const unsigned long *) addr) + (offset >> 5);
unsigned long result = offset & ~31UL;
unsigned long tmp;
if (offset >= size)
return size;
size -= result;
offset &= 31UL;
if(offset) {
/* We hold the little endian value in tmp, but then the
* shift is illegal. So we could keep a big endian value
* in tmp, like this:
*
* tmp = __swab32(*(p++));
* tmp |= ~0UL >> (32-offset);
*
* but this would decrease preformance, so we change the
* shift:
*/
tmp = *(p++);
tmp |= __swab32(~0UL >> (32-offset));
if(size < 32)
goto found_first;
if(~tmp)
goto found_middle;
size -= 32;
result += 32;
}
while(size & ~31UL) {
if(~(tmp = *(p++)))
goto found_middle;
result += 32;
size -= 32;
}
if(!size)
return result;
tmp = *p;
found_first:
/* tmp is little endian, so we would have to swab the shift,
* see above. But then we have to swab tmp below for ffz, so
* we might as well do this here.
*/
return result + ffz(__swab32(tmp) | (~0UL << size));
found_middle:
return result + ffz(__swab32(tmp));
}
/* Bitmap functions for the minix filesystem. */
#define minix_test_and_set_bit(nr,addr) ext2_set_bit(nr,addr)
#define minix_set_bit(nr,addr) ext2_set_bit(nr,addr)
#define minix_test_and_clear_bit(nr,addr) ext2_clear_bit(nr,addr)
#define minix_test_bit(nr,addr) ext2_test_bit(nr,addr)
#define minix_find_first_zero_bit(addr,size) ext2_find_first_zero_bit(addr,size)
#endif /* __KERNEL__ */
#endif /* _ASM_BITOPS_H */
