linux/include/asm-m68knommu/bitops.h
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

503 lines
11 KiB
C

#ifndef _M68KNOMMU_BITOPS_H
#define _M68KNOMMU_BITOPS_H
/*
* Copyright 1992, Linus Torvalds.
*/
#include <linux/config.h>
#include <linux/compiler.h>
#include <asm/byteorder.h> /* swab32 */
#include <asm/system.h> /* save_flags */
#ifdef __KERNEL__
/*
* Generic ffs().
*/
static inline int ffs(int x)
{
int r = 1;
if (!x)
return 0;
if (!(x & 0xffff)) {
x >>= 16;
r += 16;
}
if (!(x & 0xff)) {
x >>= 8;
r += 8;
}
if (!(x & 0xf)) {
x >>= 4;
r += 4;
}
if (!(x & 3)) {
x >>= 2;
r += 2;
}
if (!(x & 1)) {
x >>= 1;
r += 1;
}
return r;
}
/*
* Generic __ffs().
*/
static inline int __ffs(int x)
{
int r = 0;
if (!x)
return 0;
if (!(x & 0xffff)) {
x >>= 16;
r += 16;
}
if (!(x & 0xff)) {
x >>= 8;
r += 8;
}
if (!(x & 0xf)) {
x >>= 4;
r += 4;
}
if (!(x & 3)) {
x >>= 2;
r += 2;
}
if (!(x & 1)) {
x >>= 1;
r += 1;
}
return r;
}
/*
* 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(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;
}
/*
* 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;
}
static __inline__ void set_bit(int nr, volatile unsigned long * addr)
{
#ifdef CONFIG_COLDFIRE
__asm__ __volatile__ ("lea %0,%%a0; bset %1,(%%a0)"
: "+m" (((volatile char *)addr)[(nr^31) >> 3])
: "d" (nr)
: "%a0", "cc");
#else
__asm__ __volatile__ ("bset %1,%0"
: "+m" (((volatile char *)addr)[(nr^31) >> 3])
: "di" (nr)
: "cc");
#endif
}
#define __set_bit(nr, addr) set_bit(nr, addr)
/*
* 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__ void clear_bit(int nr, volatile unsigned long * addr)
{
#ifdef CONFIG_COLDFIRE
__asm__ __volatile__ ("lea %0,%%a0; bclr %1,(%%a0)"
: "+m" (((volatile char *)addr)[(nr^31) >> 3])
: "d" (nr)
: "%a0", "cc");
#else
__asm__ __volatile__ ("bclr %1,%0"
: "+m" (((volatile char *)addr)[(nr^31) >> 3])
: "di" (nr)
: "cc");
#endif
}
#define __clear_bit(nr, addr) clear_bit(nr, addr)
static __inline__ void change_bit(int nr, volatile unsigned long * addr)
{
#ifdef CONFIG_COLDFIRE
__asm__ __volatile__ ("lea %0,%%a0; bchg %1,(%%a0)"
: "+m" (((volatile char *)addr)[(nr^31) >> 3])
: "d" (nr)
: "%a0", "cc");
#else
__asm__ __volatile__ ("bchg %1,%0"
: "+m" (((volatile char *)addr)[(nr^31) >> 3])
: "di" (nr)
: "cc");
#endif
}
#define __change_bit(nr, addr) change_bit(nr, addr)
static __inline__ int test_and_set_bit(int nr, volatile unsigned long * addr)
{
char retval;
#ifdef CONFIG_COLDFIRE
__asm__ __volatile__ ("lea %1,%%a0; bset %2,(%%a0); sne %0"
: "=d" (retval), "+m" (((volatile char *)addr)[(nr^31) >> 3])
: "d" (nr)
: "%a0");
#else
__asm__ __volatile__ ("bset %2,%1; sne %0"
: "=d" (retval), "+m" (((volatile char *)addr)[(nr^31) >> 3])
: "di" (nr)
/* No clobber */);
#endif
return retval;
}
#define __test_and_set_bit(nr, addr) test_and_set_bit(nr, addr)
static __inline__ int test_and_clear_bit(int nr, volatile unsigned long * addr)
{
char retval;
#ifdef CONFIG_COLDFIRE
__asm__ __volatile__ ("lea %1,%%a0; bclr %2,(%%a0); sne %0"
: "=d" (retval), "+m" (((volatile char *)addr)[(nr^31) >> 3])
: "d" (nr)
: "%a0");
#else
__asm__ __volatile__ ("bclr %2,%1; sne %0"
: "=d" (retval), "+m" (((volatile char *)addr)[(nr^31) >> 3])
: "di" (nr)
/* No clobber */);
#endif
return retval;
}
#define __test_and_clear_bit(nr, addr) test_and_clear_bit(nr, addr)
static __inline__ int test_and_change_bit(int nr, volatile unsigned long * addr)
{
char retval;
#ifdef CONFIG_COLDFIRE
__asm__ __volatile__ ("lea %1,%%a0\n\tbchg %2,(%%a0)\n\tsne %0"
: "=d" (retval), "+m" (((volatile char *)addr)[(nr^31) >> 3])
: "d" (nr)
: "%a0");
#else
__asm__ __volatile__ ("bchg %2,%1; sne %0"
: "=d" (retval), "+m" (((volatile char *)addr)[(nr^31) >> 3])
: "di" (nr)
/* No clobber */);
#endif
return retval;
}
#define __test_and_change_bit(nr, addr) test_and_change_bit(nr, addr)
/*
* This routine doesn't need to be atomic.
*/
static __inline__ int __constant_test_bit(int nr, const volatile unsigned long * addr)
{
return ((1UL << (nr & 31)) & (((const volatile unsigned int *) addr)[nr >> 5])) != 0;
}
static __inline__ int __test_bit(int nr, const volatile unsigned long * 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)))
#define find_first_zero_bit(addr, size) \
find_next_zero_bit((addr), (size), 0)
#define find_first_bit(addr, size) \
find_next_bit((addr), (size), 0)
static __inline__ int find_next_zero_bit (void * addr, int size, int offset)
{
unsigned long *p = ((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);
}
/*
* Find next one bit in a bitmap reasonably efficiently.
*/
static __inline__ unsigned long find_next_bit(const unsigned long *addr,
unsigned long size, unsigned long offset)
{
unsigned int *p = ((unsigned int *) addr) + (offset >> 5);
unsigned int result = offset & ~31UL;
unsigned int tmp;
if (offset >= size)
return size;
size -= result;
offset &= 31UL;
if (offset) {
tmp = *p++;
tmp &= ~0UL << offset;
if (size < 32)
goto found_first;
if (tmp)
goto found_middle;
size -= 32;
result += 32;
}
while (size >= 32) {
if ((tmp = *p++) != 0)
goto found_middle;
result += 32;
size -= 32;
}
if (!size)
return result;
tmp = *p;
found_first:
tmp &= ~0UL >> (32 - size);
if (tmp == 0UL) /* Are any bits set? */
return result + size; /* Nope. */
found_middle:
return result + __ffs(tmp);
}
/*
* 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)
static __inline__ int ext2_set_bit(int nr, volatile void * addr)
{
char retval;
#ifdef CONFIG_COLDFIRE
__asm__ __volatile__ ("lea %1,%%a0; bset %2,(%%a0); sne %0"
: "=d" (retval), "+m" (((volatile char *)addr)[nr >> 3])
: "d" (nr)
: "%a0");
#else
__asm__ __volatile__ ("bset %2,%1; sne %0"
: "=d" (retval), "+m" (((volatile char *)addr)[nr >> 3])
: "di" (nr)
/* No clobber */);
#endif
return retval;
}
static __inline__ int ext2_clear_bit(int nr, volatile void * addr)
{
char retval;
#ifdef CONFIG_COLDFIRE
__asm__ __volatile__ ("lea %1,%%a0; bclr %2,(%%a0); sne %0"
: "=d" (retval), "+m" (((volatile char *)addr)[nr >> 3])
: "d" (nr)
: "%a0");
#else
__asm__ __volatile__ ("bclr %2,%1; sne %0"
: "=d" (retval), "+m" (((volatile char *)addr)[nr >> 3])
: "di" (nr)
/* No clobber */);
#endif
return retval;
}
#define ext2_set_bit_atomic(lock, nr, addr) \
({ \
int ret; \
spin_lock(lock); \
ret = ext2_set_bit((nr), (addr)); \
spin_unlock(lock); \
ret; \
})
#define ext2_clear_bit_atomic(lock, nr, addr) \
({ \
int ret; \
spin_lock(lock); \
ret = ext2_clear_bit((nr), (addr)); \
spin_unlock(lock); \
ret; \
})
static __inline__ int ext2_test_bit(int nr, const volatile void * addr)
{
char retval;
#ifdef CONFIG_COLDFIRE
__asm__ __volatile__ ("lea %1,%%a0; btst %2,(%%a0); sne %0"
: "=d" (retval)
: "m" (((const volatile char *)addr)[nr >> 3]), "d" (nr)
: "%a0");
#else
__asm__ __volatile__ ("btst %2,%1; sne %0"
: "=d" (retval)
: "m" (((const volatile char *)addr)[nr >> 3]), "di" (nr)
/* No clobber */);
#endif
return retval;
}
#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(void *addr, unsigned long size, unsigned long offset)
{
unsigned long *p = ((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) test_and_set_bit(nr,addr)
#define minix_set_bit(nr,addr) set_bit(nr,addr)
#define minix_test_and_clear_bit(nr,addr) test_and_clear_bit(nr,addr)
#define minix_test_bit(nr,addr) test_bit(nr,addr)
#define minix_find_first_zero_bit(addr,size) find_first_zero_bit(addr,size)
/**
* hweightN - returns the hamming weight of a N-bit word
* @x: the word to weigh
*
* The Hamming Weight of a number is the total number of bits set in it.
*/
#define hweight32(x) generic_hweight32(x)
#define hweight16(x) generic_hweight16(x)
#define hweight8(x) generic_hweight8(x)
#endif /* __KERNEL__ */
/*
* fls: find last bit set.
*/
#define fls(x) generic_fls(x)
#endif /* _M68KNOMMU_BITOPS_H */