/* * PowerPC atomic bit operations. * * Merged version by David Gibson . * Based on ppc64 versions by: Dave Engebretsen, Todd Inglett, Don * Reed, Pat McCarthy, Peter Bergner, Anton Blanchard. They * originally took it from the ppc32 code. * * Within a word, bits are numbered LSB first. Lot's of places make * this assumption by directly testing bits with (val & (1< 1 word) bitmaps on a * big-endian system because, unlike little endian, the number of each * bit depends on the word size. * * The bitop functions are defined to work on unsigned longs, so for a * ppc64 system the bits end up numbered: * |63..............0|127............64|191...........128|255...........196| * and on ppc32: * |31.....0|63....31|95....64|127...96|159..128|191..160|223..192|255..224| * * There are a few little-endian macros used mostly for filesystem * bitmaps, these work on similar bit arrays layouts, but * byte-oriented: * |7...0|15...8|23...16|31...24|39...32|47...40|55...48|63...56| * * The main difference is that bit 3-5 (64b) or 3-4 (32b) in the bit * number field needs to be reversed compared to the big-endian bit * fields. This can be achieved by XOR with 0x38 (64b) or 0x18 (32b). * * 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_POWERPC_BITOPS_H #define _ASM_POWERPC_BITOPS_H #ifdef __KERNEL__ #ifndef _LINUX_BITOPS_H #error only can be included directly #endif #include #include #include /* * clear_bit doesn't imply a memory barrier */ #define smp_mb__before_clear_bit() smp_mb() #define smp_mb__after_clear_bit() smp_mb() #define BITOP_LE_SWIZZLE ((BITS_PER_LONG-1) & ~0x7) /* Macro for generating the ***_bits() functions */ #define DEFINE_BITOP(fn, op, prefix, postfix) \ static __inline__ void fn(unsigned long mask, \ volatile unsigned long *_p) \ { \ unsigned long old; \ unsigned long *p = (unsigned long *)_p; \ __asm__ __volatile__ ( \ prefix \ "1:" PPC_LLARX(%0,0,%3,0) "\n" \ stringify_in_c(op) "%0,%0,%2\n" \ PPC405_ERR77(0,%3) \ PPC_STLCX "%0,0,%3\n" \ "bne- 1b\n" \ postfix \ : "=&r" (old), "+m" (*p) \ : "r" (mask), "r" (p) \ : "cc", "memory"); \ } DEFINE_BITOP(set_bits, or, "", "") DEFINE_BITOP(clear_bits, andc, "", "") DEFINE_BITOP(clear_bits_unlock, andc, PPC_RELEASE_BARRIER, "") DEFINE_BITOP(change_bits, xor, "", "") static __inline__ void set_bit(int nr, volatile unsigned long *addr) { set_bits(BIT_MASK(nr), addr + BIT_WORD(nr)); } static __inline__ void clear_bit(int nr, volatile unsigned long *addr) { clear_bits(BIT_MASK(nr), addr + BIT_WORD(nr)); } static __inline__ void clear_bit_unlock(int nr, volatile unsigned long *addr) { clear_bits_unlock(BIT_MASK(nr), addr + BIT_WORD(nr)); } static __inline__ void change_bit(int nr, volatile unsigned long *addr) { change_bits(BIT_MASK(nr), addr + BIT_WORD(nr)); } /* Like DEFINE_BITOP(), with changes to the arguments to 'op' and the output * operands. */ #define DEFINE_TESTOP(fn, op, prefix, postfix, eh) \ static __inline__ unsigned long fn( \ unsigned long mask, \ volatile unsigned long *_p) \ { \ unsigned long old, t; \ unsigned long *p = (unsigned long *)_p; \ __asm__ __volatile__ ( \ prefix \ "1:" PPC_LLARX(%0,0,%3,eh) "\n" \ stringify_in_c(op) "%1,%0,%2\n" \ PPC405_ERR77(0,%3) \ PPC_STLCX "%1,0,%3\n" \ "bne- 1b\n" \ postfix \ : "=&r" (old), "=&r" (t) \ : "r" (mask), "r" (p) \ : "cc", "memory"); \ return (old & mask); \ } DEFINE_TESTOP(test_and_set_bits, or, PPC_ATOMIC_ENTRY_BARRIER, PPC_ATOMIC_EXIT_BARRIER, 0) DEFINE_TESTOP(test_and_set_bits_lock, or, "", PPC_ACQUIRE_BARRIER, 1) DEFINE_TESTOP(test_and_clear_bits, andc, PPC_ATOMIC_ENTRY_BARRIER, PPC_ATOMIC_EXIT_BARRIER, 0) DEFINE_TESTOP(test_and_change_bits, xor, PPC_ATOMIC_ENTRY_BARRIER, PPC_ATOMIC_EXIT_BARRIER, 0) static __inline__ int test_and_set_bit(unsigned long nr, volatile unsigned long *addr) { return test_and_set_bits(BIT_MASK(nr), addr + BIT_WORD(nr)) != 0; } static __inline__ int test_and_set_bit_lock(unsigned long nr, volatile unsigned long *addr) { return test_and_set_bits_lock(BIT_MASK(nr), addr + BIT_WORD(nr)) != 0; } static __inline__ int test_and_clear_bit(unsigned long nr, volatile unsigned long *addr) { return test_and_clear_bits(BIT_MASK(nr), addr + BIT_WORD(nr)) != 0; } static __inline__ int test_and_change_bit(unsigned long nr, volatile unsigned long *addr) { return test_and_change_bits(BIT_MASK(nr), addr + BIT_WORD(nr)) != 0; } #include static __inline__ void __clear_bit_unlock(int nr, volatile unsigned long *addr) { __asm__ __volatile__(PPC_RELEASE_BARRIER "" ::: "memory"); __clear_bit(nr, addr); } /* * Return the zero-based bit position (LE, not IBM bit numbering) of * the most significant 1-bit in a double word. */ static __inline__ __attribute__((const)) int __ilog2(unsigned long x) { int lz; asm (PPC_CNTLZL "%0,%1" : "=r" (lz) : "r" (x)); return BITS_PER_LONG - 1 - lz; } static inline __attribute__((const)) int __ilog2_u32(u32 n) { int bit; asm ("cntlzw %0,%1" : "=r" (bit) : "r" (n)); return 31 - bit; } #ifdef __powerpc64__ static inline __attribute__((const)) int __ilog2_u64(u64 n) { int bit; asm ("cntlzd %0,%1" : "=r" (bit) : "r" (n)); return 63 - bit; } #endif /* * Determines the bit position of the least significant 0 bit in the * specified double word. The returned bit position will be * zero-based, starting from the right side (63/31 - 0). */ static __inline__ unsigned long ffz(unsigned long x) { /* no zero exists anywhere in the 8 byte area. */ if ((x = ~x) == 0) return BITS_PER_LONG; /* * Calculate the bit position of the least significant '1' bit in x * (since x has been changed this will actually be the least significant * '0' bit in * the original x). Note: (x & -x) gives us a mask that * is the least significant * (RIGHT-most) 1-bit of the value in x. */ 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) { unsigned long i = (unsigned long)x; return __ilog2(i & -i) + 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; } static __inline__ unsigned long __fls(unsigned long x) { return __ilog2(x); } /* * 64-bit can do this using one cntlzd (count leading zeroes doubleword) * instruction; for 32-bit we use the generic version, which does two * 32-bit fls calls. */ #ifdef __powerpc64__ static __inline__ int fls64(__u64 x) { int lz; asm ("cntlzd %0,%1" : "=r" (lz) : "r" (x)); return 64 - lz; } #else #include #endif /* __powerpc64__ */ #ifdef CONFIG_PPC64 unsigned int __arch_hweight8(unsigned int w); unsigned int __arch_hweight16(unsigned int w); unsigned int __arch_hweight32(unsigned int w); unsigned long __arch_hweight64(__u64 w); #include #else #include #endif #include /* Little-endian versions */ #include /* Bitmap functions for the ext2 filesystem */ #include #include #endif /* __KERNEL__ */ #endif /* _ASM_POWERPC_BITOPS_H */