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Diffstat (limited to 'include/asm-xtensa/bitops.h')
| -rw-r--r-- | include/asm-xtensa/bitops.h | 446 |
1 files changed, 446 insertions, 0 deletions
diff --git a/include/asm-xtensa/bitops.h b/include/asm-xtensa/bitops.h new file mode 100644 index 00000000000..d395ef226c3 --- /dev/null +++ b/include/asm-xtensa/bitops.h @@ -0,0 +1,446 @@ +/* + * include/asm-xtensa/bitops.h + * + * Atomic operations that C can't guarantee us.Useful for resource counting etc. + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (C) 2001 - 2005 Tensilica Inc. + */ + +#ifndef _XTENSA_BITOPS_H +#define _XTENSA_BITOPS_H + +#ifdef __KERNEL__ + +#include <asm/processor.h> +#include <asm/byteorder.h> +#include <asm/system.h> + +#ifdef CONFIG_SMP +# error SMP not supported on this architecture +#endif + +static __inline__ void set_bit(int nr, volatile void * addr) +{ + unsigned long mask = 1 << (nr & 0x1f); + unsigned long *a = ((unsigned long *)addr) + (nr >> 5); + unsigned long flags; + + local_irq_save(flags); + *a |= mask; + local_irq_restore(flags); +} + +static __inline__ void __set_bit(int nr, volatile unsigned long * addr) +{ + unsigned long mask = 1 << (nr & 0x1f); + unsigned long *a = ((unsigned long *)addr) + (nr >> 5); + + *a |= mask; +} + +static __inline__ void clear_bit(int nr, volatile void * addr) +{ + unsigned long mask = 1 << (nr & 0x1f); + unsigned long *a = ((unsigned long *)addr) + (nr >> 5); + unsigned long flags; + + local_irq_save(flags); + *a &= ~mask; + local_irq_restore(flags); +} + +static __inline__ void __clear_bit(int nr, volatile unsigned long *addr) +{ + unsigned long mask = 1 << (nr & 0x1f); + unsigned long *a = ((unsigned long *)addr) + (nr >> 5); + + *a &= ~mask; +} + +/* + * 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 change_bit(int nr, volatile void * addr) +{ + unsigned long mask = 1 << (nr & 0x1f); + unsigned long *a = ((unsigned long *)addr) + (nr >> 5); + unsigned long flags; + + local_irq_save(flags); + *a ^= mask; + local_irq_restore(flags); +} + +static __inline__ void __change_bit(int nr, volatile void * addr) +{ + unsigned long mask = 1 << (nr & 0x1f); + unsigned long *a = ((unsigned long *)addr) + (nr >> 5); + + *a ^= mask; +} + +static __inline__ int test_and_set_bit(int nr, volatile void * addr) +{ + unsigned long retval; + unsigned long mask = 1 << (nr & 0x1f); + unsigned long *a = ((unsigned long *)addr) + (nr >> 5); + unsigned long flags; + + local_irq_save(flags); + retval = (mask & *a) != 0; + *a |= mask; + local_irq_restore(flags); + + return retval; +} + +static __inline__ int __test_and_set_bit(int nr, volatile void * addr) +{ + unsigned long retval; + unsigned long mask = 1 << (nr & 0x1f); + unsigned long *a = ((unsigned long *)addr) + (nr >> 5); + + retval = (mask & *a) != 0; + *a |= mask; + + return retval; +} + +static __inline__ int test_and_clear_bit(int nr, volatile void * addr) +{ + unsigned long retval; + unsigned long mask = 1 << (nr & 0x1f); + unsigned long *a = ((unsigned long *)addr) + (nr >> 5); + unsigned long flags; + + local_irq_save(flags); + retval = (mask & *a) != 0; + *a &= ~mask; + local_irq_restore(flags); + + return retval; +} + +static __inline__ int __test_and_clear_bit(int nr, volatile void * addr) +{ + unsigned long mask = 1 << (nr & 0x1f); + unsigned long *a = ((unsigned long *)addr) + (nr >> 5); + unsigned long old = *a; + + *a = old & ~mask; + return (old & mask) != 0; +} + +static __inline__ int test_and_change_bit(int nr, volatile void * addr) +{ + unsigned long retval; + unsigned long mask = 1 << (nr & 0x1f); + unsigned long *a = ((unsigned long *)addr) + (nr >> 5); + unsigned long flags; + + local_irq_save(flags); + + retval = (mask & *a) != 0; + *a ^= mask; + local_irq_restore(flags); + + return retval; +} + +/* + * non-atomic version; can be reordered + */ + +static __inline__ int __test_and_change_bit(int nr, volatile void *addr) +{ + unsigned long mask = 1 << (nr & 0x1f); + unsigned long *a = ((unsigned long *)addr) + (nr >> 5); + unsigned long old = *a; + + *a = old ^ mask; + return (old & mask) != 0; +} + +static __inline__ int test_bit(int nr, const volatile void *addr) +{ + return 1UL & (((const volatile unsigned int *)addr)[nr>>5] >> (nr&31)); +} + +#if XCHAL_HAVE_NSAU + +static __inline__ int __cntlz (unsigned long x) +{ + int lz; + asm ("nsau %0, %1" : "=r" (lz) : "r" (x)); + return 31 - lz; +} + +#else + +static __inline__ int __cntlz (unsigned long x) +{ + unsigned long sum, x1, x2, x4, x8, x16; + x1 = x & 0xAAAAAAAA; + x2 = x & 0xCCCCCCCC; + x4 = x & 0xF0F0F0F0; + x8 = x & 0xFF00FF00; + x16 = x & 0xFFFF0000; + sum = x2 ? 2 : 0; + sum += (x16 != 0) * 16; + sum += (x8 != 0) * 8; + sum += (x4 != 0) * 4; + sum += (x1 != 0); + + return sum; +} + +#endif + +/* + * ffz: Find first zero in word. Undefined if no zero exists. + * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1). + */ + +static __inline__ int ffz(unsigned long x) +{ + if ((x = ~x) == 0) + return 32; + return __cntlz(x & -x); +} + +/* + * __ffs: Find first bit set in word. Return 0 for bit 0 + */ + +static __inline__ int __ffs(unsigned long x) +{ + return __cntlz(x & -x); +} + +/* + * ffs: Find first bit set in word. 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(unsigned long x) +{ + return __cntlz(x & -x) + 1; +} + +/* + * fls: Find last (most-significant) bit set in word. + * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32. + */ + +static __inline__ int fls (unsigned int x) +{ + return __cntlz(x); +} + +static __inline__ int +find_next_bit(const unsigned long *addr, int size, int offset) +{ + const unsigned long *p = 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 << 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) + +static __inline__ int +find_next_zero_bit(const unsigned long *addr, int size, int offset) +{ + const unsigned long *p = 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 find_first_zero_bit(addr, size) \ + find_next_zero_bit((addr), (size), 0) + +#ifdef __XTENSA_EL__ +# define ext2_set_bit(nr,addr) __test_and_set_bit((nr), (addr)) +# define ext2_set_bit_atomic(lock,nr,addr) test_and_set_bit((nr),(addr)) +# define ext2_clear_bit(nr,addr) __test_and_clear_bit((nr), (addr)) +# define ext2_clear_bit_atomic(lock,nr,addr) test_and_clear_bit((nr),(addr)) +# define ext2_test_bit(nr,addr) test_bit((nr), (addr)) +# define ext2_find_first_zero_bit(addr, size) find_first_zero_bit((addr),(size)) +# define ext2_find_next_zero_bit(addr, size, offset) \ + find_next_zero_bit((addr), (size), (offset)) +#elif defined(__XTENSA_EB__) +# define ext2_set_bit(nr,addr) __test_and_set_bit((nr) ^ 0x18, (addr)) +# define ext2_set_bit_atomic(lock,nr,addr) test_and_set_bit((nr) ^ 0x18, (addr)) +# define ext2_clear_bit(nr,addr) __test_and_clear_bit((nr) ^ 18, (addr)) +# define ext2_clear_bit_atomic(lock,nr,addr) test_and_clear_bit((nr)^0x18,(addr)) +# define ext2_test_bit(nr,addr) test_bit((nr) ^ 0x18, (addr)) +# 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)); +} + +#else +# error processor byte order undefined! +#endif + + +#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; +} + + +/* 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) + +#endif /* __KERNEL__ */ + +#endif /* _XTENSA_BITOPS_H */ |