diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-frv/bitops.h |
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!
Diffstat (limited to 'include/asm-frv/bitops.h')
-rw-r--r-- | include/asm-frv/bitops.h | 341 |
1 files changed, 341 insertions, 0 deletions
diff --git a/include/asm-frv/bitops.h b/include/asm-frv/bitops.h new file mode 100644 index 000000000000..b664bd5b6663 --- /dev/null +++ b/include/asm-frv/bitops.h @@ -0,0 +1,341 @@ +/* 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 */ |