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-ppc/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-ppc/bitops.h')
-rw-r--r-- | include/asm-ppc/bitops.h | 460 |
1 files changed, 460 insertions, 0 deletions
diff --git a/include/asm-ppc/bitops.h b/include/asm-ppc/bitops.h new file mode 100644 index 00000000000..e30f536fd83 --- /dev/null +++ b/include/asm-ppc/bitops.h @@ -0,0 +1,460 @@ +/* + * 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__ */ |