linux/include/asm-ppc/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

461 lines
10 KiB
C

/*
* bitops.h: Bit string operations on the ppc
*/
#ifdef __KERNEL__
#ifndef _PPC_BITOPS_H
#define _PPC_BITOPS_H
#include <linux/config.h>
#include <linux/compiler.h>
#include <asm/byteorder.h>
#include <asm/atomic.h>
/*
* The test_and_*_bit operations are taken to imply a memory barrier
* on SMP systems.
*/
#ifdef CONFIG_SMP
#define SMP_WMB "eieio\n"
#define SMP_MB "\nsync"
#else
#define SMP_WMB
#define SMP_MB
#endif /* CONFIG_SMP */
static __inline__ void set_bit(int nr, volatile unsigned long * addr)
{
unsigned long old;
unsigned long mask = 1 << (nr & 0x1f);
unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
__asm__ __volatile__("\n\
1: lwarx %0,0,%3 \n\
or %0,%0,%2 \n"
PPC405_ERR77(0,%3)
" stwcx. %0,0,%3 \n\
bne- 1b"
: "=&r" (old), "=m" (*p)
: "r" (mask), "r" (p), "m" (*p)
: "cc" );
}
/*
* non-atomic version
*/
static __inline__ void __set_bit(int nr, volatile unsigned long *addr)
{
unsigned long mask = 1 << (nr & 0x1f);
unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
*p |= mask;
}
/*
* clear_bit doesn't imply a memory barrier
*/
#define smp_mb__before_clear_bit() smp_mb()
#define smp_mb__after_clear_bit() smp_mb()
static __inline__ void clear_bit(int nr, volatile unsigned long *addr)
{
unsigned long old;
unsigned long mask = 1 << (nr & 0x1f);
unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
__asm__ __volatile__("\n\
1: lwarx %0,0,%3 \n\
andc %0,%0,%2 \n"
PPC405_ERR77(0,%3)
" stwcx. %0,0,%3 \n\
bne- 1b"
: "=&r" (old), "=m" (*p)
: "r" (mask), "r" (p), "m" (*p)
: "cc");
}
/*
* non-atomic version
*/
static __inline__ void __clear_bit(int nr, volatile unsigned long *addr)
{
unsigned long mask = 1 << (nr & 0x1f);
unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
*p &= ~mask;
}
static __inline__ void change_bit(int nr, volatile unsigned long *addr)
{
unsigned long old;
unsigned long mask = 1 << (nr & 0x1f);
unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
__asm__ __volatile__("\n\
1: lwarx %0,0,%3 \n\
xor %0,%0,%2 \n"
PPC405_ERR77(0,%3)
" stwcx. %0,0,%3 \n\
bne- 1b"
: "=&r" (old), "=m" (*p)
: "r" (mask), "r" (p), "m" (*p)
: "cc");
}
/*
* non-atomic version
*/
static __inline__ void __change_bit(int nr, volatile unsigned long *addr)
{
unsigned long mask = 1 << (nr & 0x1f);
unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
*p ^= mask;
}
/*
* test_and_*_bit do imply a memory barrier (?)
*/
static __inline__ int test_and_set_bit(int nr, volatile unsigned long *addr)
{
unsigned int old, t;
unsigned int mask = 1 << (nr & 0x1f);
volatile unsigned int *p = ((volatile unsigned int *)addr) + (nr >> 5);
__asm__ __volatile__(SMP_WMB "\n\
1: lwarx %0,0,%4 \n\
or %1,%0,%3 \n"
PPC405_ERR77(0,%4)
" stwcx. %1,0,%4 \n\
bne 1b"
SMP_MB
: "=&r" (old), "=&r" (t), "=m" (*p)
: "r" (mask), "r" (p), "m" (*p)
: "cc", "memory");
return (old & mask) != 0;
}
/*
* non-atomic version
*/
static __inline__ int __test_and_set_bit(int nr, volatile unsigned long *addr)
{
unsigned long mask = 1 << (nr & 0x1f);
unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
unsigned long old = *p;
*p = old | mask;
return (old & mask) != 0;
}
static __inline__ int test_and_clear_bit(int nr, volatile unsigned long *addr)
{
unsigned int old, t;
unsigned int mask = 1 << (nr & 0x1f);
volatile unsigned int *p = ((volatile unsigned int *)addr) + (nr >> 5);
__asm__ __volatile__(SMP_WMB "\n\
1: lwarx %0,0,%4 \n\
andc %1,%0,%3 \n"
PPC405_ERR77(0,%4)
" stwcx. %1,0,%4 \n\
bne 1b"
SMP_MB
: "=&r" (old), "=&r" (t), "=m" (*p)
: "r" (mask), "r" (p), "m" (*p)
: "cc", "memory");
return (old & mask) != 0;
}
/*
* non-atomic version
*/
static __inline__ int __test_and_clear_bit(int nr, volatile unsigned long *addr)
{
unsigned long mask = 1 << (nr & 0x1f);
unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
unsigned long old = *p;
*p = old & ~mask;
return (old & mask) != 0;
}
static __inline__ int test_and_change_bit(int nr, volatile unsigned long *addr)
{
unsigned int old, t;
unsigned int mask = 1 << (nr & 0x1f);
volatile unsigned int *p = ((volatile unsigned int *)addr) + (nr >> 5);
__asm__ __volatile__(SMP_WMB "\n\
1: lwarx %0,0,%4 \n\
xor %1,%0,%3 \n"
PPC405_ERR77(0,%4)
" stwcx. %1,0,%4 \n\
bne 1b"
SMP_MB
: "=&r" (old), "=&r" (t), "=m" (*p)
: "r" (mask), "r" (p), "m" (*p)
: "cc", "memory");
return (old & mask) != 0;
}
/*
* non-atomic version
*/
static __inline__ int __test_and_change_bit(int nr, volatile unsigned long *addr)
{
unsigned long mask = 1 << (nr & 0x1f);
unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
unsigned long old = *p;
*p = old ^ mask;
return (old & mask) != 0;
}
static __inline__ int test_bit(int nr, __const__ volatile unsigned long *addr)
{
return ((addr[nr >> 5] >> (nr & 0x1f)) & 1) != 0;
}
/* Return the bit position of the most significant 1 bit in a word */
static __inline__ int __ilog2(unsigned long x)
{
int lz;
asm ("cntlzw %0,%1" : "=r" (lz) : "r" (x));
return 31 - lz;
}
static __inline__ int ffz(unsigned long x)
{
if ((x = ~x) == 0)
return 32;
return __ilog2(x & -x);
}
static inline int __ffs(unsigned long x)
{
return __ilog2(x & -x);
}
/*
* 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).
*/
static __inline__ int ffs(int x)
{
return __ilog2(x & -x) + 1;
}
/*
* fls: find last (most-significant) bit set.
* Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
*/
static __inline__ int fls(unsigned int x)
{
int lz;
asm ("cntlzw %0,%1" : "=r" (lz) : "r" (x));
return 32 - lz;
}
/*
* 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)
/*
* Find the first bit set in a 140-bit bitmap.
* The first 100 bits are unlikely to be set.
*/
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;
}
/**
* find_next_bit - find the next set bit in a memory region
* @addr: The address to base the search on
* @offset: The bitnumber to start searching at
* @size: The maximum size to search
*/
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);
}
/**
* find_first_bit - find the first set bit in a memory region
* @addr: The address to start the search at
* @size: The maximum size to search
*
* Returns the bit-number of the first set bit, not the number of the byte
* containing a bit.
*/
#define find_first_bit(addr, size) \
find_next_bit((addr), (size), 0)
/*
* This implementation of find_{first,next}_zero_bit was stolen from
* Linus' asm-alpha/bitops.h.
*/
#define find_first_zero_bit(addr, size) \
find_next_zero_bit((addr), (size), 0)
static __inline__ unsigned long find_next_zero_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 >> (32-offset);
if (size < 32)
goto found_first;
if (tmp != ~0U)
goto found_middle;
size -= 32;
result += 32;
}
while (size >= 32) {
if ((tmp = *p++) != ~0U)
goto found_middle;
result += 32;
size -= 32;
}
if (!size)
return result;
tmp = *p;
found_first:
tmp |= ~0UL << size;
if (tmp == ~0UL) /* Are any bits zero? */
return result + size; /* Nope. */
found_middle:
return result + ffz(tmp);
}
#define ext2_set_bit(nr, addr) __test_and_set_bit((nr) ^ 0x18, (unsigned long *)(addr))
#define ext2_set_bit_atomic(lock, nr, addr) test_and_set_bit((nr) ^ 0x18, (unsigned long *)(addr))
#define ext2_clear_bit(nr, addr) __test_and_clear_bit((nr) ^ 0x18, (unsigned long *)(addr))
#define ext2_clear_bit_atomic(lock, nr, addr) test_and_clear_bit((nr) ^ 0x18, (unsigned long *)(addr))
static __inline__ int ext2_test_bit(int nr, __const__ void * addr)
{
__const__ unsigned char *ADDR = (__const__ unsigned char *) addr;
return (ADDR[nr >> 3] >> (nr & 7)) & 1;
}
/*
* This implementation of ext2_find_{first,next}_zero_bit was stolen from
* Linus' asm-alpha/bitops.h and modified for a big-endian machine.
*/
#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)
{
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 = cpu_to_le32p(p++);
tmp |= ~0UL >> (32-offset);
if (size < 32)
goto found_first;
if (tmp != ~0U)
goto found_middle;
size -= 32;
result += 32;
}
while (size >= 32) {
if ((tmp = cpu_to_le32p(p++)) != ~0U)
goto found_middle;
result += 32;
size -= 32;
}
if (!size)
return result;
tmp = cpu_to_le32p(p);
found_first:
tmp |= ~0U << size;
if (tmp == ~0UL) /* Are any bits zero? */
return result + size; /* Nope. */
found_middle:
return result + ffz(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) ((void)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 /* _PPC_BITOPS_H */
#endif /* __KERNEL__ */