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bitops.h
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1 #ifndef _PARISC_BITOPS_H
2 #define _PARISC_BITOPS_H
3 
4 #ifndef _LINUX_BITOPS_H
5 #error only <linux/bitops.h> can be included directly
6 #endif
7 
8 #include <linux/compiler.h>
9 #include <asm/types.h> /* for BITS_PER_LONG/SHIFT_PER_LONG */
10 #include <asm/byteorder.h>
11 #include <linux/atomic.h>
12 
13 /*
14  * HP-PARISC specific bit operations
15  * for a detailed description of the functions please refer
16  * to include/asm-i386/bitops.h or kerneldoc
17  */
18 
19 #define CHOP_SHIFTCOUNT(x) (((unsigned long) (x)) & (BITS_PER_LONG - 1))
20 
21 
22 #define smp_mb__before_clear_bit() smp_mb()
23 #define smp_mb__after_clear_bit() smp_mb()
24 
25 /* See http://marc.theaimsgroup.com/?t=108826637900003 for discussion
26  * on use of volatile and __*_bit() (set/clear/change):
27  * *_bit() want use of volatile.
28  * __*_bit() are "relaxed" and don't use spinlock or volatile.
29  */
30 
31 static __inline__ void set_bit(int nr, volatile unsigned long * addr)
32 {
33  unsigned long mask = 1UL << CHOP_SHIFTCOUNT(nr);
34  unsigned long flags;
35 
36  addr += (nr >> SHIFT_PER_LONG);
37  _atomic_spin_lock_irqsave(addr, flags);
38  *addr |= mask;
39  _atomic_spin_unlock_irqrestore(addr, flags);
40 }
41 
42 static __inline__ void clear_bit(int nr, volatile unsigned long * addr)
43 {
44  unsigned long mask = ~(1UL << CHOP_SHIFTCOUNT(nr));
45  unsigned long flags;
46 
47  addr += (nr >> SHIFT_PER_LONG);
48  _atomic_spin_lock_irqsave(addr, flags);
49  *addr &= mask;
50  _atomic_spin_unlock_irqrestore(addr, flags);
51 }
52 
53 static __inline__ void change_bit(int nr, volatile unsigned long * addr)
54 {
55  unsigned long mask = 1UL << CHOP_SHIFTCOUNT(nr);
56  unsigned long flags;
57 
58  addr += (nr >> SHIFT_PER_LONG);
59  _atomic_spin_lock_irqsave(addr, flags);
60  *addr ^= mask;
61  _atomic_spin_unlock_irqrestore(addr, flags);
62 }
63 
64 static __inline__ int test_and_set_bit(int nr, volatile unsigned long * addr)
65 {
66  unsigned long mask = 1UL << CHOP_SHIFTCOUNT(nr);
67  unsigned long old;
68  unsigned long flags;
69  int set;
70 
71  addr += (nr >> SHIFT_PER_LONG);
72  _atomic_spin_lock_irqsave(addr, flags);
73  old = *addr;
74  set = (old & mask) ? 1 : 0;
75  if (!set)
76  *addr = old | mask;
77  _atomic_spin_unlock_irqrestore(addr, flags);
78 
79  return set;
80 }
81 
82 static __inline__ int test_and_clear_bit(int nr, volatile unsigned long * addr)
83 {
84  unsigned long mask = 1UL << CHOP_SHIFTCOUNT(nr);
85  unsigned long old;
86  unsigned long flags;
87  int set;
88 
89  addr += (nr >> SHIFT_PER_LONG);
90  _atomic_spin_lock_irqsave(addr, flags);
91  old = *addr;
92  set = (old & mask) ? 1 : 0;
93  if (set)
94  *addr = old & ~mask;
95  _atomic_spin_unlock_irqrestore(addr, flags);
96 
97  return set;
98 }
99 
100 static __inline__ int test_and_change_bit(int nr, volatile unsigned long * addr)
101 {
102  unsigned long mask = 1UL << CHOP_SHIFTCOUNT(nr);
103  unsigned long oldbit;
104  unsigned long flags;
105 
106  addr += (nr >> SHIFT_PER_LONG);
107  _atomic_spin_lock_irqsave(addr, flags);
108  oldbit = *addr;
109  *addr = oldbit ^ mask;
110  _atomic_spin_unlock_irqrestore(addr, flags);
111 
112  return (oldbit & mask) ? 1 : 0;
113 }
114 
115 #include <asm-generic/bitops/non-atomic.h>
116 
117 #ifdef __KERNEL__
118 
138 static __inline__ unsigned long __ffs(unsigned long x)
139 {
140  unsigned long ret;
141 
142  __asm__(
143 #ifdef CONFIG_64BIT
144  " ldi 63,%1\n"
145  " extrd,u,*<> %0,63,32,%%r0\n"
146  " extrd,u,*TR %0,31,32,%0\n" /* move top 32-bits down */
147  " addi -32,%1,%1\n"
148 #else
149  " ldi 31,%1\n"
150 #endif
151  " extru,<> %0,31,16,%%r0\n"
152  " extru,TR %0,15,16,%0\n" /* xxxx0000 -> 0000xxxx */
153  " addi -16,%1,%1\n"
154  " extru,<> %0,31,8,%%r0\n"
155  " extru,TR %0,23,8,%0\n" /* 0000xx00 -> 000000xx */
156  " addi -8,%1,%1\n"
157  " extru,<> %0,31,4,%%r0\n"
158  " extru,TR %0,27,4,%0\n" /* 000000x0 -> 0000000x */
159  " addi -4,%1,%1\n"
160  " extru,<> %0,31,2,%%r0\n"
161  " extru,TR %0,29,2,%0\n" /* 0000000y, 1100b -> 0011b */
162  " addi -2,%1,%1\n"
163  " extru,= %0,31,1,%%r0\n" /* check last bit */
164  " addi -1,%1,%1\n"
165  : "+r" (x), "=r" (ret) );
166  return ret;
167 }
168 
169 #include <asm-generic/bitops/ffz.h>
170 
171 /*
172  * ffs: find first bit set. returns 1 to BITS_PER_LONG or 0 (if none set)
173  * This is defined the same way as the libc and compiler builtin
174  * ffs routines, therefore differs in spirit from the above ffz (man ffs).
175  */
176 static __inline__ int ffs(int x)
177 {
178  return x ? (__ffs((unsigned long)x) + 1) : 0;
179 }
180 
181 /*
182  * fls: find last (most significant) bit set.
183  * fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
184  */
185 
186 static __inline__ int fls(int x)
187 {
188  int ret;
189  if (!x)
190  return 0;
191 
192  __asm__(
193  " ldi 1,%1\n"
194  " extru,<> %0,15,16,%%r0\n"
195  " zdep,TR %0,15,16,%0\n" /* xxxx0000 */
196  " addi 16,%1,%1\n"
197  " extru,<> %0,7,8,%%r0\n"
198  " zdep,TR %0,23,24,%0\n" /* xx000000 */
199  " addi 8,%1,%1\n"
200  " extru,<> %0,3,4,%%r0\n"
201  " zdep,TR %0,27,28,%0\n" /* x0000000 */
202  " addi 4,%1,%1\n"
203  " extru,<> %0,1,2,%%r0\n"
204  " zdep,TR %0,29,30,%0\n" /* y0000000 (y&3 = 0) */
205  " addi 2,%1,%1\n"
206  " extru,= %0,0,1,%%r0\n"
207  " addi 1,%1,%1\n" /* if y & 8, add 1 */
208  : "+r" (x), "=r" (ret) );
209 
210  return ret;
211 }
212 
213 #include <asm-generic/bitops/__fls.h>
214 #include <asm-generic/bitops/fls64.h>
215 #include <asm-generic/bitops/hweight.h>
216 #include <asm-generic/bitops/lock.h>
217 #include <asm-generic/bitops/sched.h>
218 
219 #endif /* __KERNEL__ */
220 
221 #include <asm-generic/bitops/find.h>
222 
223 #ifdef __KERNEL__
224 
225 #include <asm-generic/bitops/le.h>
226 #include <asm-generic/bitops/ext2-atomic-setbit.h>
227 
228 #endif /* __KERNEL__ */
229 
230 #endif /* _PARISC_BITOPS_H */
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