aboutsummaryrefslogtreecommitdiff
path: root/include/asm-cris/bitops.h
blob: f8a6747693148350c3cce205b29bf82f6fa0a5f6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
/* asm/bitops.h for Linux/CRIS
 *
 * TODO: asm versions if speed is needed
 *
 * All bit operations return 0 if the bit was cleared before the
 * operation and != 0 if it was not.
 *
 * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
 */

#ifndef _CRIS_BITOPS_H
#define _CRIS_BITOPS_H

/* Currently this is unsuitable for consumption outside the kernel.  */
#ifdef __KERNEL__ 

#include <asm/arch/bitops.h>
#include <asm/system.h>
#include <asm/atomic.h>
#include <linux/compiler.h>

/*
 * Some hacks to defeat gcc over-optimizations..
 */
struct __dummy { unsigned long a[100]; };
#define ADDR (*(struct __dummy *) addr)
#define CONST_ADDR (*(const struct __dummy *) addr)

/*
 * set_bit - Atomically set a bit in memory
 * @nr: the bit to set
 * @addr: the address to start counting from
 *
 * This function is atomic and may not be reordered.  See __set_bit()
 * if you do not require the atomic guarantees.
 * Note that @nr may be almost arbitrarily large; this function is not
 * restricted to acting on a single-word quantity.
 */

#define set_bit(nr, addr)    (void)test_and_set_bit(nr, addr)

#define __set_bit(nr, addr)    (void)__test_and_set_bit(nr, addr)

/*
 * clear_bit - Clears a bit in memory
 * @nr: Bit to clear
 * @addr: Address to start counting from
 *
 * clear_bit() is atomic and may not be reordered.  However, it does
 * not contain a memory barrier, so if it is used for locking purposes,
 * you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit()
 * in order to ensure changes are visible on other processors.
 */

#define clear_bit(nr, addr)  (void)test_and_clear_bit(nr, addr)

#define __clear_bit(nr, addr)  (void)__test_and_clear_bit(nr, addr)

/*
 * change_bit - Toggle a bit in memory
 * @nr: Bit to change
 * @addr: Address to start counting from
 *
 * change_bit() is atomic and may not be reordered.
 * Note that @nr may be almost arbitrarily large; this function is not
 * restricted to acting on a single-word quantity.
 */

#define change_bit(nr, addr) (void)test_and_change_bit(nr, addr)

/*
 * __change_bit - Toggle a bit in memory
 * @nr: the bit to change
 * @addr: the address to start counting from
 *
 * Unlike change_bit(), this function is non-atomic and may be reordered.
 * If it's called on the same region of memory simultaneously, the effect
 * may be that only one operation succeeds.
 */

#define __change_bit(nr, addr) (void)__test_and_change_bit(nr, addr)

/**
 * test_and_set_bit - Set a bit and return its old value
 * @nr: Bit to set
 * @addr: Address to count from
 *
 * This operation is atomic and cannot be reordered.  
 * It also implies a memory barrier.
 */

static inline int test_and_set_bit(int nr, volatile unsigned long *addr)
{
	unsigned int mask, retval;
	unsigned long flags;
	unsigned int *adr = (unsigned int *)addr;
	
	adr += nr >> 5;
	mask = 1 << (nr & 0x1f);
	cris_atomic_save(addr, flags);
	retval = (mask & *adr) != 0;
	*adr |= mask;
	cris_atomic_restore(addr, flags);
	return retval;
}

static inline int __test_and_set_bit(int nr, volatile unsigned long *addr)
{
	unsigned int mask, retval;
	unsigned int *adr = (unsigned int *)addr;
	
	adr += nr >> 5;
	mask = 1 << (nr & 0x1f);
	retval = (mask & *adr) != 0;
	*adr |= mask;
	return retval;
}

/*
 * clear_bit() doesn't provide any barrier for the compiler.
 */
#define smp_mb__before_clear_bit()      barrier()
#define smp_mb__after_clear_bit()       barrier()

/**
 * test_and_clear_bit - Clear a bit and return its old value
 * @nr: Bit to clear
 * @addr: Address to count from
 *
 * This operation is atomic and cannot be reordered.  
 * It also implies a memory barrier.
 */

static inline int test_and_clear_bit(int nr, volatile unsigned long *addr)
{
	unsigned int mask, retval;
	unsigned long flags;
	unsigned int *adr = (unsigned int *)addr;
	
	adr += nr >> 5;
	mask = 1 << (nr & 0x1f);
	cris_atomic_save(addr, flags);
	retval = (mask & *adr) != 0;
	*adr &= ~mask;
	cris_atomic_restore(addr, flags);
	return retval;
}

/**
 * __test_and_clear_bit - Clear a bit and return its old value
 * @nr: Bit to clear
 * @addr: Address to count from
 *
 * This operation is non-atomic and can be reordered.  
 * If two examples of this operation race, one can appear to succeed
 * but actually fail.  You must protect multiple accesses with a lock.
 */

static inline int __test_and_clear_bit(int nr, volatile unsigned long *addr)
{
	unsigned int mask, retval;
	unsigned int *adr = (unsigned int *)addr;
	
	adr += nr >> 5;
	mask = 1 << (nr & 0x1f);
	retval = (mask & *adr) != 0;
	*adr &= ~mask;
	return retval;
}
/**
 * test_and_change_bit - Change a bit and return its old value
 * @nr: Bit to change
 * @addr: Address to count from
 *
 * This operation is atomic and cannot be reordered.  
 * It also implies a memory barrier.
 */

static inline int test_and_change_bit(int nr, volatile unsigned long *addr)
{
	unsigned int mask, retval;
	unsigned long flags;
	unsigned int *adr = (unsigned int *)addr;
	adr += nr >> 5;
	mask = 1 << (nr & 0x1f);
	cris_atomic_save(addr, flags);
	retval = (mask & *adr) != 0;
	*adr ^= mask;
	cris_atomic_restore(addr, flags);
	return retval;
}

/* WARNING: non atomic and it can be reordered! */

static inline int __test_and_change_bit(int nr, volatile unsigned long *addr)
{
	unsigned int mask, retval;
	unsigned int *adr = (unsigned int *)addr;

	adr += nr >> 5;
	mask = 1 << (nr & 0x1f);
	retval = (mask & *adr) != 0;
	*adr ^= mask;

	return retval;
}

/**
 * test_bit - Determine whether a bit is set
 * @nr: bit number to test
 * @addr: Address to start counting from
 *
 * This routine doesn't need to be atomic.
 */

static inline int test_bit(int nr, const volatile unsigned long *addr)
{
	unsigned int mask;
	unsigned int *adr = (unsigned int *)addr;
	
	adr += nr >> 5;
	mask = 1 << (nr & 0x1f);
	return ((mask & *adr) != 0);
}

/*
 * Find-bit routines..
 */

/*
 * Since we define it "external", it collides with the built-in
 * definition, which doesn't have the same semantics.  We don't want to
 * use -fno-builtin, so just hide the name ffs.
 */
#define ffs kernel_ffs

/*
 * fls: find last bit set.
 */

#define fls(x) generic_fls(x)
#define fls64(x)   generic_fls64(x)

/*
 * hweightN - returns the hamming weight of a N-bit word
 * @x: the word to weigh
 *
 * The Hamming Weight of a number is the total number of bits set in it.
 */

#define hweight32(x) generic_hweight32(x)
#define hweight16(x) generic_hweight16(x)
#define hweight8(x) generic_hweight8(x)

/**
 * find_next_zero_bit - find the first zero 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 int find_next_zero_bit (const unsigned long * addr, int size, int 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) {
		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);
}

/**
 * find_next_bit - find the first 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__ int find_next_bit(const unsigned long *addr, int size, int 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) {
                tmp = *(p++);
                tmp &= (~0UL << 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 >> (32 - size));
        if (tmp == 0UL)        /* Are any bits set? */
                return result + size; /* Nope. */
found_middle:
        return result + __ffs(tmp);
}

/**
 * find_first_zero_bit - find the first zero 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 zero bit, not the number of the byte
 * containing a bit.
 */

#define find_first_zero_bit(addr, size) \
        find_next_zero_bit((addr), (size), 0)
#define find_first_bit(addr, size) \
        find_next_bit((addr), (size), 0)

#define ext2_set_bit                 test_and_set_bit
#define ext2_set_bit_atomic(l,n,a)   test_and_set_bit(n,a)
#define ext2_clear_bit               test_and_clear_bit
#define ext2_clear_bit_atomic(l,n,a) test_and_clear_bit(n,a)
#define ext2_test_bit                test_bit
#define ext2_find_first_zero_bit     find_first_zero_bit
#define ext2_find_next_zero_bit      find_next_zero_bit

/* Bitmap functions for the minix filesystem.  */
#define minix_set_bit(nr,addr) test_and_set_bit(nr,addr)
#define minix_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)

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 (unlikely(b[3]))
		return __ffs(b[3]) + 96;
	if (b[4])
		return __ffs(b[4]) + 128;
	return __ffs(b[5]) + 32 + 128;
}

#endif /* __KERNEL__ */

#endif /* _CRIS_BITOPS_H */