1
linux/include/asm-parisc/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

521 lines
13 KiB
C

#ifndef _PARISC_BITOPS_H
#define _PARISC_BITOPS_H
#include <linux/compiler.h>
#include <asm/system.h>
#include <asm/byteorder.h>
#include <asm/atomic.h>
/*
* HP-PARISC specific bit operations
* for a detailed description of the functions please refer
* to include/asm-i386/bitops.h or kerneldoc
*/
#ifdef __LP64__
# define SHIFT_PER_LONG 6
#ifndef BITS_PER_LONG
# define BITS_PER_LONG 64
#endif
#else
# define SHIFT_PER_LONG 5
#ifndef BITS_PER_LONG
# define BITS_PER_LONG 32
#endif
#endif
#define CHOP_SHIFTCOUNT(x) ((x) & (BITS_PER_LONG - 1))
#define smp_mb__before_clear_bit() smp_mb()
#define smp_mb__after_clear_bit() smp_mb()
static __inline__ void set_bit(int nr, volatile unsigned long * address)
{
unsigned long mask;
unsigned long *addr = (unsigned long *) address;
unsigned long flags;
addr += (nr >> SHIFT_PER_LONG);
mask = 1L << CHOP_SHIFTCOUNT(nr);
_atomic_spin_lock_irqsave(addr, flags);
*addr |= mask;
_atomic_spin_unlock_irqrestore(addr, flags);
}
static __inline__ void __set_bit(int nr, volatile unsigned long * address)
{
unsigned long mask;
unsigned long *addr = (unsigned long *) address;
addr += (nr >> SHIFT_PER_LONG);
mask = 1L << CHOP_SHIFTCOUNT(nr);
*addr |= mask;
}
static __inline__ void clear_bit(int nr, volatile unsigned long * address)
{
unsigned long mask;
unsigned long *addr = (unsigned long *) address;
unsigned long flags;
addr += (nr >> SHIFT_PER_LONG);
mask = 1L << CHOP_SHIFTCOUNT(nr);
_atomic_spin_lock_irqsave(addr, flags);
*addr &= ~mask;
_atomic_spin_unlock_irqrestore(addr, flags);
}
static __inline__ void __clear_bit(unsigned long nr, volatile unsigned long * address)
{
unsigned long mask;
unsigned long *addr = (unsigned long *) address;
addr += (nr >> SHIFT_PER_LONG);
mask = 1L << CHOP_SHIFTCOUNT(nr);
*addr &= ~mask;
}
static __inline__ void change_bit(int nr, volatile unsigned long * address)
{
unsigned long mask;
unsigned long *addr = (unsigned long *) address;
unsigned long flags;
addr += (nr >> SHIFT_PER_LONG);
mask = 1L << CHOP_SHIFTCOUNT(nr);
_atomic_spin_lock_irqsave(addr, flags);
*addr ^= mask;
_atomic_spin_unlock_irqrestore(addr, flags);
}
static __inline__ void __change_bit(int nr, volatile unsigned long * address)
{
unsigned long mask;
unsigned long *addr = (unsigned long *) address;
addr += (nr >> SHIFT_PER_LONG);
mask = 1L << CHOP_SHIFTCOUNT(nr);
*addr ^= mask;
}
static __inline__ int test_and_set_bit(int nr, volatile unsigned long * address)
{
unsigned long mask;
unsigned long *addr = (unsigned long *) address;
int oldbit;
unsigned long flags;
addr += (nr >> SHIFT_PER_LONG);
mask = 1L << CHOP_SHIFTCOUNT(nr);
_atomic_spin_lock_irqsave(addr, flags);
oldbit = (*addr & mask) ? 1 : 0;
*addr |= mask;
_atomic_spin_unlock_irqrestore(addr, flags);
return oldbit;
}
static __inline__ int __test_and_set_bit(int nr, volatile unsigned long * address)
{
unsigned long mask;
unsigned long *addr = (unsigned long *) address;
int oldbit;
addr += (nr >> SHIFT_PER_LONG);
mask = 1L << CHOP_SHIFTCOUNT(nr);
oldbit = (*addr & mask) ? 1 : 0;
*addr |= mask;
return oldbit;
}
static __inline__ int test_and_clear_bit(int nr, volatile unsigned long * address)
{
unsigned long mask;
unsigned long *addr = (unsigned long *) address;
int oldbit;
unsigned long flags;
addr += (nr >> SHIFT_PER_LONG);
mask = 1L << CHOP_SHIFTCOUNT(nr);
_atomic_spin_lock_irqsave(addr, flags);
oldbit = (*addr & mask) ? 1 : 0;
*addr &= ~mask;
_atomic_spin_unlock_irqrestore(addr, flags);
return oldbit;
}
static __inline__ int __test_and_clear_bit(int nr, volatile unsigned long * address)
{
unsigned long mask;
unsigned long *addr = (unsigned long *) address;
int oldbit;
addr += (nr >> SHIFT_PER_LONG);
mask = 1L << CHOP_SHIFTCOUNT(nr);
oldbit = (*addr & mask) ? 1 : 0;
*addr &= ~mask;
return oldbit;
}
static __inline__ int test_and_change_bit(int nr, volatile unsigned long * address)
{
unsigned long mask;
unsigned long *addr = (unsigned long *) address;
int oldbit;
unsigned long flags;
addr += (nr >> SHIFT_PER_LONG);
mask = 1L << CHOP_SHIFTCOUNT(nr);
_atomic_spin_lock_irqsave(addr, flags);
oldbit = (*addr & mask) ? 1 : 0;
*addr ^= mask;
_atomic_spin_unlock_irqrestore(addr, flags);
return oldbit;
}
static __inline__ int __test_and_change_bit(int nr, volatile unsigned long * address)
{
unsigned long mask;
unsigned long *addr = (unsigned long *) address;
int oldbit;
addr += (nr >> SHIFT_PER_LONG);
mask = 1L << CHOP_SHIFTCOUNT(nr);
oldbit = (*addr & mask) ? 1 : 0;
*addr ^= mask;
return oldbit;
}
static __inline__ int test_bit(int nr, const volatile unsigned long *address)
{
unsigned long mask;
const unsigned long *addr = (const unsigned long *)address;
addr += (nr >> SHIFT_PER_LONG);
mask = 1L << CHOP_SHIFTCOUNT(nr);
return !!(*addr & mask);
}
#ifdef __KERNEL__
/**
* __ffs - find first bit in word. returns 0 to "BITS_PER_LONG-1".
* @word: The word to search
*
* __ffs() return is undefined if no bit is set.
*
* 32-bit fast __ffs by LaMont Jones "lamont At hp com".
* 64-bit enhancement by Grant Grundler "grundler At parisc-linux org".
* (with help from willy/jejb to get the semantics right)
*
* This algorithm avoids branches by making use of nullification.
* One side effect of "extr" instructions is it sets PSW[N] bit.
* How PSW[N] (nullify next insn) gets set is determined by the
* "condition" field (eg "<>" or "TR" below) in the extr* insn.
* Only the 1st and one of either the 2cd or 3rd insn will get executed.
* Each set of 3 insn will get executed in 2 cycles on PA8x00 vs 16 or so
* cycles for each mispredicted branch.
*/
static __inline__ unsigned long __ffs(unsigned long x)
{
unsigned long ret;
__asm__(
#if BITS_PER_LONG > 32
" ldi 63,%1\n"
" extrd,u,*<> %0,63,32,%%r0\n"
" extrd,u,*TR %0,31,32,%0\n" /* move top 32-bits down */
" addi -32,%1,%1\n"
#else
" ldi 31,%1\n"
#endif
" extru,<> %0,31,16,%%r0\n"
" extru,TR %0,15,16,%0\n" /* xxxx0000 -> 0000xxxx */
" addi -16,%1,%1\n"
" extru,<> %0,31,8,%%r0\n"
" extru,TR %0,23,8,%0\n" /* 0000xx00 -> 000000xx */
" addi -8,%1,%1\n"
" extru,<> %0,31,4,%%r0\n"
" extru,TR %0,27,4,%0\n" /* 000000x0 -> 0000000x */
" addi -4,%1,%1\n"
" extru,<> %0,31,2,%%r0\n"
" extru,TR %0,29,2,%0\n" /* 0000000y, 1100b -> 0011b */
" addi -2,%1,%1\n"
" extru,= %0,31,1,%%r0\n" /* check last bit */
" addi -1,%1,%1\n"
: "+r" (x), "=r" (ret) );
return ret;
}
/* Undefined if no bit is zero. */
#define ffz(x) __ffs(~x)
/*
* ffs: find first bit set. returns 1 to BITS_PER_LONG or 0 (if none 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 x ? (__ffs((unsigned long)x) + 1) : 0;
}
/*
* fls: find last (most significant) bit set.
* fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
*/
static __inline__ int fls(int x)
{
int ret;
if (!x)
return 0;
__asm__(
" ldi 1,%1\n"
" extru,<> %0,15,16,%%r0\n"
" zdep,TR %0,15,16,%0\n" /* xxxx0000 */
" addi 16,%1,%1\n"
" extru,<> %0,7,8,%%r0\n"
" zdep,TR %0,23,24,%0\n" /* xx000000 */
" addi 8,%1,%1\n"
" extru,<> %0,3,4,%%r0\n"
" zdep,TR %0,27,28,%0\n" /* x0000000 */
" addi 4,%1,%1\n"
" extru,<> %0,1,2,%%r0\n"
" zdep,TR %0,29,30,%0\n" /* y0000000 (y&3 = 0) */
" addi 2,%1,%1\n"
" extru,= %0,0,1,%%r0\n"
" addi 1,%1,%1\n" /* if y & 8, add 1 */
: "+r" (x), "=r" (ret) );
return ret;
}
/*
* hweightN: returns the hamming weight (i.e. the number
* of bits set) of a N-bit word
*/
#define hweight64(x) \
({ \
unsigned long __x = (x); \
unsigned int __w; \
__w = generic_hweight32((unsigned int) __x); \
__w += generic_hweight32((unsigned int) (__x>>32)); \
__w; \
})
#define hweight32(x) generic_hweight32(x)
#define hweight16(x) generic_hweight16(x)
#define hweight8(x) generic_hweight8(x)
/*
* 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)
{
#ifndef __LP64__
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;
#else
if (unlikely(b[0]))
return __ffs(b[0]);
if (unlikely(((unsigned int)b[1])))
return __ffs(b[1]) + 64;
if (b[1] >> 32)
return __ffs(b[1] >> 32) + 96;
return __ffs(b[2]) + 128;
#endif
}
#endif /* __KERNEL__ */
/*
* 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 void * addr, unsigned long size, unsigned long offset)
{
const unsigned long * p = ((unsigned long *) addr) + (offset >> SHIFT_PER_LONG);
unsigned long result = offset & ~(BITS_PER_LONG-1);
unsigned long tmp;
if (offset >= size)
return size;
size -= result;
offset &= (BITS_PER_LONG-1);
if (offset) {
tmp = *(p++);
tmp |= ~0UL >> (BITS_PER_LONG-offset);
if (size < BITS_PER_LONG)
goto found_first;
if (~tmp)
goto found_middle;
size -= BITS_PER_LONG;
result += BITS_PER_LONG;
}
while (size & ~(BITS_PER_LONG -1)) {
if (~(tmp = *(p++)))
goto found_middle;
result += BITS_PER_LONG;
size -= BITS_PER_LONG;
}
if (!size)
return result;
tmp = *p;
found_first:
tmp |= ~0UL << size;
found_middle:
return result + ffz(tmp);
}
static __inline__ unsigned long find_next_bit(const unsigned long *addr, unsigned long size, unsigned long offset)
{
const unsigned long *p = addr + (offset >> 6);
unsigned long result = offset & ~(BITS_PER_LONG-1);
unsigned long tmp;
if (offset >= size)
return size;
size -= result;
offset &= (BITS_PER_LONG-1);
if (offset) {
tmp = *(p++);
tmp &= (~0UL << offset);
if (size < BITS_PER_LONG)
goto found_first;
if (tmp)
goto found_middle;
size -= BITS_PER_LONG;
result += BITS_PER_LONG;
}
while (size & ~(BITS_PER_LONG-1)) {
if ((tmp = *(p++)))
goto found_middle;
result += BITS_PER_LONG;
size -= BITS_PER_LONG;
}
if (!size)
return result;
tmp = *p;
found_first:
tmp &= (~0UL >> (BITS_PER_LONG - 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)
#define _EXT2_HAVE_ASM_BITOPS_
#ifdef __KERNEL__
/*
* test_and_{set,clear}_bit guarantee atomicity without
* disabling interrupts.
*/
#ifdef __LP64__
#define ext2_set_bit(nr, addr) __test_and_set_bit((nr) ^ 0x38, (unsigned long *)addr)
#define ext2_set_bit_atomic(l,nr,addr) test_and_set_bit((nr) ^ 0x38, (unsigned long *)addr)
#define ext2_clear_bit(nr, addr) __test_and_clear_bit((nr) ^ 0x38, (unsigned long *)addr)
#define ext2_clear_bit_atomic(l,nr,addr) test_and_clear_bit((nr) ^ 0x38, (unsigned long *)addr)
#else
#define ext2_set_bit(nr, addr) __test_and_set_bit((nr) ^ 0x18, (unsigned long *)addr)
#define ext2_set_bit_atomic(l,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(l,nr,addr) test_and_clear_bit((nr) ^ 0x18, (unsigned long *)addr)
#endif
#endif /* __KERNEL__ */
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)
extern __inline__ unsigned long ext2_find_next_zero_bit(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;
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 /* _PARISC_BITOPS_H */