2 * bitops.h: Bit string operations on the ppc
9 #include <linux/config.h>
10 #include <asm/byteorder.h>
11 #include <asm/atomic.h>
14 * The test_and_*_bit operations are taken to imply a memory barrier
18 #define SMP_WMB "eieio\n"
19 #define SMP_MB "\nsync"
23 #endif /* CONFIG_SMP */
26 * These used to be if'd out here because using : "cc" as a constraint
27 * resulted in errors from egcs. Things appear to be OK with gcc-2.95.
29 static __inline__ void set_bit(int nr, volatile void * addr)
32 unsigned long mask = 1 << (nr & 0x1f);
33 unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
35 __asm__ __volatile__("\n\
41 : "=&r" (old), "=m" (*p)
42 : "r" (mask), "r" (p), "m" (*p)
49 static __inline__ void __set_bit(int nr, volatile void *addr)
51 unsigned long mask = 1 << (nr & 0x1f);
52 unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
58 * clear_bit doesn't imply a memory barrier
60 #define smp_mb__before_clear_bit() smp_mb()
61 #define smp_mb__after_clear_bit() smp_mb()
63 static __inline__ void clear_bit(int nr, volatile void *addr)
66 unsigned long mask = 1 << (nr & 0x1f);
67 unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
69 __asm__ __volatile__("\n\
75 : "=&r" (old), "=m" (*p)
76 : "r" (mask), "r" (p), "m" (*p)
83 static __inline__ void __clear_bit(int nr, volatile void *addr)
85 unsigned long mask = 1 << (nr & 0x1f);
86 unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
91 static __inline__ void change_bit(int nr, volatile void *addr)
94 unsigned long mask = 1 << (nr & 0x1f);
95 unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
97 __asm__ __volatile__("\n\
103 : "=&r" (old), "=m" (*p)
104 : "r" (mask), "r" (p), "m" (*p)
111 static __inline__ void __change_bit(int nr, volatile void *addr)
113 unsigned long mask = 1 << (nr & 0x1f);
114 unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
120 * test_and_*_bit do imply a memory barrier (?)
122 static __inline__ int test_and_set_bit(int nr, volatile void *addr)
125 unsigned int mask = 1 << (nr & 0x1f);
126 volatile unsigned int *p = ((volatile unsigned int *)addr) + (nr >> 5);
128 __asm__ __volatile__(SMP_WMB "\n\
135 : "=&r" (old), "=&r" (t), "=m" (*p)
136 : "r" (mask), "r" (p), "m" (*p)
139 return (old & mask) != 0;
145 static __inline__ int __test_and_set_bit(int nr, volatile void *addr)
147 unsigned long mask = 1 << (nr & 0x1f);
148 unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
149 unsigned long old = *p;
152 return (old & mask) != 0;
155 static __inline__ int test_and_clear_bit(int nr, volatile void *addr)
158 unsigned int mask = 1 << (nr & 0x1f);
159 volatile unsigned int *p = ((volatile unsigned int *)addr) + (nr >> 5);
161 __asm__ __volatile__(SMP_WMB "\n\
168 : "=&r" (old), "=&r" (t), "=m" (*p)
169 : "r" (mask), "r" (p), "m" (*p)
172 return (old & mask) != 0;
178 static __inline__ int __test_and_clear_bit(int nr, volatile void *addr)
180 unsigned long mask = 1 << (nr & 0x1f);
181 unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
182 unsigned long old = *p;
185 return (old & mask) != 0;
188 static __inline__ int test_and_change_bit(int nr, volatile void *addr)
191 unsigned int mask = 1 << (nr & 0x1f);
192 volatile unsigned int *p = ((volatile unsigned int *)addr) + (nr >> 5);
194 __asm__ __volatile__(SMP_WMB "\n\
201 : "=&r" (old), "=&r" (t), "=m" (*p)
202 : "r" (mask), "r" (p), "m" (*p)
205 return (old & mask) != 0;
211 static __inline__ int __test_and_change_bit(int nr, volatile void *addr)
213 unsigned long mask = 1 << (nr & 0x1f);
214 unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
215 unsigned long old = *p;
218 return (old & mask) != 0;
221 static __inline__ int test_bit(int nr, __const__ volatile void *addr)
223 __const__ unsigned int *p = (__const__ unsigned int *) addr;
225 return ((p[nr >> 5] >> (nr & 0x1f)) & 1) != 0;
228 /* Return the bit position of the most significant 1 bit in a word */
229 static __inline__ int __ilog2(unsigned int x)
233 asm ("cntlzw %0,%1" : "=r" (lz) : "r" (x));
237 static __inline__ int ffz(unsigned int x)
241 return __ilog2(x & -x);
245 * ffs: find first bit set. This is defined the same way as
246 * the libc and compiler builtin ffs routines, therefore
247 * differs in spirit from the above ffz (man ffs).
249 static __inline__ int ffs(int x)
251 return __ilog2(x & -x) + 1;
255 * hweightN: returns the hamming weight (i.e. the number
256 * of bits set) of a N-bit word
259 #define hweight32(x) generic_hweight32(x)
260 #define hweight16(x) generic_hweight16(x)
261 #define hweight8(x) generic_hweight8(x)
264 * This implementation of find_{first,next}_zero_bit was stolen from
265 * Linus' asm-alpha/bitops.h.
267 #define find_first_zero_bit(addr, size) \
268 find_next_zero_bit((addr), (size), 0)
270 static __inline__ unsigned long find_next_zero_bit(void * addr,
271 unsigned long size, unsigned long offset)
273 unsigned int * p = ((unsigned int *) addr) + (offset >> 5);
274 unsigned int result = offset & ~31UL;
283 tmp |= ~0UL >> (32-offset);
292 if ((tmp = *p++) != ~0U)
302 if (tmp == ~0UL) /* Are any bits zero? */
303 return result + size; /* Nope. */
305 return result + ffz(tmp);
309 #define ext2_set_bit(nr, addr) __test_and_set_bit((nr) ^ 0x18, addr)
310 #define ext2_clear_bit(nr, addr) __test_and_clear_bit((nr) ^ 0x18, addr)
312 static __inline__ int ext2_test_bit(int nr, __const__ void * addr)
314 __const__ unsigned char *ADDR = (__const__ unsigned char *) addr;
316 return (ADDR[nr >> 3] >> (nr & 7)) & 1;
320 * This implementation of ext2_find_{first,next}_zero_bit was stolen from
321 * Linus' asm-alpha/bitops.h and modified for a big-endian machine.
324 #define ext2_find_first_zero_bit(addr, size) \
325 ext2_find_next_zero_bit((addr), (size), 0)
327 static __inline__ unsigned long ext2_find_next_zero_bit(void *addr,
328 unsigned long size, unsigned long offset)
330 unsigned int *p = ((unsigned int *) addr) + (offset >> 5);
331 unsigned int result = offset & ~31UL;
339 tmp = cpu_to_le32p(p++);
340 tmp |= ~0UL >> (32-offset);
349 if ((tmp = cpu_to_le32p(p++)) != ~0U)
356 tmp = cpu_to_le32p(p);
359 if (tmp == ~0UL) /* Are any bits zero? */
360 return result + size; /* Nope. */
362 return result + ffz(tmp);
365 /* Bitmap functions for the minix filesystem. */
366 #define minix_test_and_set_bit(nr,addr) ext2_set_bit(nr,addr)
367 #define minix_set_bit(nr,addr) ((void)ext2_set_bit(nr,addr))
368 #define minix_test_and_clear_bit(nr,addr) ext2_clear_bit(nr,addr)
369 #define minix_test_bit(nr,addr) ext2_test_bit(nr,addr)
370 #define minix_find_first_zero_bit(addr,size) ext2_find_first_zero_bit(addr,size)
372 #endif /* _PPC_BITOPS_H */
373 #endif /* __KERNEL__ */