xref: /openbmc/linux/arch/s390/include/asm/bitops.h (revision 588b48ca)
1 /*
2  *    Copyright IBM Corp. 1999,2013
3  *
4  *    Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>,
5  *
6  * The description below was taken in large parts from the powerpc
7  * bitops header file:
8  * Within a word, bits are numbered LSB first.  Lot's of places make
9  * this assumption by directly testing bits with (val & (1<<nr)).
10  * This can cause confusion for large (> 1 word) bitmaps on a
11  * big-endian system because, unlike little endian, the number of each
12  * bit depends on the word size.
13  *
14  * The bitop functions are defined to work on unsigned longs, so for an
15  * s390x system the bits end up numbered:
16  *   |63..............0|127............64|191...........128|255...........192|
17  * and on s390:
18  *   |31.....0|63....32|95....64|127...96|159..128|191..160|223..192|255..224|
19  *
20  * There are a few little-endian macros used mostly for filesystem
21  * bitmaps, these work on similar bit arrays layouts, but
22  * byte-oriented:
23  *   |7...0|15...8|23...16|31...24|39...32|47...40|55...48|63...56|
24  *
25  * The main difference is that bit 3-5 (64b) or 3-4 (32b) in the bit
26  * number field needs to be reversed compared to the big-endian bit
27  * fields. This can be achieved by XOR with 0x38 (64b) or 0x18 (32b).
28  *
29  * We also have special functions which work with an MSB0 encoding:
30  * on an s390x system the bits are numbered:
31  *   |0..............63|64............127|128...........191|192...........255|
32  * and on s390:
33  *   |0.....31|32....63|64....95|96...127|128..159|160..191|192..223|224..255|
34  *
35  * The main difference is that bit 0-63 (64b) or 0-31 (32b) in the bit
36  * number field needs to be reversed compared to the LSB0 encoded bit
37  * fields. This can be achieved by XOR with 0x3f (64b) or 0x1f (32b).
38  *
39  */
40 
41 #ifndef _S390_BITOPS_H
42 #define _S390_BITOPS_H
43 
44 #ifndef _LINUX_BITOPS_H
45 #error only <linux/bitops.h> can be included directly
46 #endif
47 
48 #include <linux/typecheck.h>
49 #include <linux/compiler.h>
50 #include <asm/barrier.h>
51 
52 #define __BITOPS_NO_BARRIER	"\n"
53 
54 #ifndef CONFIG_64BIT
55 
56 #define __BITOPS_OR		"or"
57 #define __BITOPS_AND		"nr"
58 #define __BITOPS_XOR		"xr"
59 #define __BITOPS_BARRIER	"\n"
60 
61 #define __BITOPS_LOOP(__addr, __val, __op_string, __barrier)	\
62 ({								\
63 	unsigned long __old, __new;				\
64 								\
65 	typecheck(unsigned long *, (__addr));			\
66 	asm volatile(						\
67 		"	l	%0,%2\n"			\
68 		"0:	lr	%1,%0\n"			\
69 		__op_string "	%1,%3\n"			\
70 		"	cs	%0,%1,%2\n"			\
71 		"	jl	0b"				\
72 		: "=&d" (__old), "=&d" (__new), "+Q" (*(__addr))\
73 		: "d" (__val)					\
74 		: "cc", "memory");				\
75 	__old;							\
76 })
77 
78 #else /* CONFIG_64BIT */
79 
80 #ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
81 
82 #define __BITOPS_OR		"laog"
83 #define __BITOPS_AND		"lang"
84 #define __BITOPS_XOR		"laxg"
85 #define __BITOPS_BARRIER	"bcr	14,0\n"
86 
87 #define __BITOPS_LOOP(__addr, __val, __op_string, __barrier)	\
88 ({								\
89 	unsigned long __old;					\
90 								\
91 	typecheck(unsigned long *, (__addr));			\
92 	asm volatile(						\
93 		__barrier					\
94 		__op_string "	%0,%2,%1\n"			\
95 		__barrier					\
96 		: "=d" (__old),	"+Q" (*(__addr))		\
97 		: "d" (__val)					\
98 		: "cc", "memory");				\
99 	__old;							\
100 })
101 
102 #else /* CONFIG_HAVE_MARCH_Z196_FEATURES */
103 
104 #define __BITOPS_OR		"ogr"
105 #define __BITOPS_AND		"ngr"
106 #define __BITOPS_XOR		"xgr"
107 #define __BITOPS_BARRIER	"\n"
108 
109 #define __BITOPS_LOOP(__addr, __val, __op_string, __barrier)	\
110 ({								\
111 	unsigned long __old, __new;				\
112 								\
113 	typecheck(unsigned long *, (__addr));			\
114 	asm volatile(						\
115 		"	lg	%0,%2\n"			\
116 		"0:	lgr	%1,%0\n"			\
117 		__op_string "	%1,%3\n"			\
118 		"	csg	%0,%1,%2\n"			\
119 		"	jl	0b"				\
120 		: "=&d" (__old), "=&d" (__new), "+Q" (*(__addr))\
121 		: "d" (__val)					\
122 		: "cc", "memory");				\
123 	__old;							\
124 })
125 
126 #endif /* CONFIG_HAVE_MARCH_Z196_FEATURES */
127 
128 #endif /* CONFIG_64BIT */
129 
130 #define __BITOPS_WORDS(bits) (((bits) + BITS_PER_LONG - 1) / BITS_PER_LONG)
131 
132 static inline unsigned long *
133 __bitops_word(unsigned long nr, volatile unsigned long *ptr)
134 {
135 	unsigned long addr;
136 
137 	addr = (unsigned long)ptr + ((nr ^ (nr & (BITS_PER_LONG - 1))) >> 3);
138 	return (unsigned long *)addr;
139 }
140 
141 static inline unsigned char *
142 __bitops_byte(unsigned long nr, volatile unsigned long *ptr)
143 {
144 	return ((unsigned char *)ptr) + ((nr ^ (BITS_PER_LONG - 8)) >> 3);
145 }
146 
147 static inline void set_bit(unsigned long nr, volatile unsigned long *ptr)
148 {
149 	unsigned long *addr = __bitops_word(nr, ptr);
150 	unsigned long mask;
151 
152 #ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES
153 	if (__builtin_constant_p(nr)) {
154 		unsigned char *caddr = __bitops_byte(nr, ptr);
155 
156 		asm volatile(
157 			"oi	%0,%b1\n"
158 			: "+Q" (*caddr)
159 			: "i" (1 << (nr & 7))
160 			: "cc", "memory");
161 		return;
162 	}
163 #endif
164 	mask = 1UL << (nr & (BITS_PER_LONG - 1));
165 	__BITOPS_LOOP(addr, mask, __BITOPS_OR, __BITOPS_NO_BARRIER);
166 }
167 
168 static inline void clear_bit(unsigned long nr, volatile unsigned long *ptr)
169 {
170 	unsigned long *addr = __bitops_word(nr, ptr);
171 	unsigned long mask;
172 
173 #ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES
174 	if (__builtin_constant_p(nr)) {
175 		unsigned char *caddr = __bitops_byte(nr, ptr);
176 
177 		asm volatile(
178 			"ni	%0,%b1\n"
179 			: "+Q" (*caddr)
180 			: "i" (~(1 << (nr & 7)))
181 			: "cc", "memory");
182 		return;
183 	}
184 #endif
185 	mask = ~(1UL << (nr & (BITS_PER_LONG - 1)));
186 	__BITOPS_LOOP(addr, mask, __BITOPS_AND, __BITOPS_NO_BARRIER);
187 }
188 
189 static inline void change_bit(unsigned long nr, volatile unsigned long *ptr)
190 {
191 	unsigned long *addr = __bitops_word(nr, ptr);
192 	unsigned long mask;
193 
194 #ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES
195 	if (__builtin_constant_p(nr)) {
196 		unsigned char *caddr = __bitops_byte(nr, ptr);
197 
198 		asm volatile(
199 			"xi	%0,%b1\n"
200 			: "+Q" (*caddr)
201 			: "i" (1 << (nr & 7))
202 			: "cc", "memory");
203 		return;
204 	}
205 #endif
206 	mask = 1UL << (nr & (BITS_PER_LONG - 1));
207 	__BITOPS_LOOP(addr, mask, __BITOPS_XOR, __BITOPS_NO_BARRIER);
208 }
209 
210 static inline int
211 test_and_set_bit(unsigned long nr, volatile unsigned long *ptr)
212 {
213 	unsigned long *addr = __bitops_word(nr, ptr);
214 	unsigned long old, mask;
215 
216 	mask = 1UL << (nr & (BITS_PER_LONG - 1));
217 	old = __BITOPS_LOOP(addr, mask, __BITOPS_OR, __BITOPS_BARRIER);
218 	return (old & mask) != 0;
219 }
220 
221 static inline int
222 test_and_clear_bit(unsigned long nr, volatile unsigned long *ptr)
223 {
224 	unsigned long *addr = __bitops_word(nr, ptr);
225 	unsigned long old, mask;
226 
227 	mask = ~(1UL << (nr & (BITS_PER_LONG - 1)));
228 	old = __BITOPS_LOOP(addr, mask, __BITOPS_AND, __BITOPS_BARRIER);
229 	return (old & ~mask) != 0;
230 }
231 
232 static inline int
233 test_and_change_bit(unsigned long nr, volatile unsigned long *ptr)
234 {
235 	unsigned long *addr = __bitops_word(nr, ptr);
236 	unsigned long old, mask;
237 
238 	mask = 1UL << (nr & (BITS_PER_LONG - 1));
239 	old = __BITOPS_LOOP(addr, mask, __BITOPS_XOR, __BITOPS_BARRIER);
240 	return (old & mask) != 0;
241 }
242 
243 static inline void __set_bit(unsigned long nr, volatile unsigned long *ptr)
244 {
245 	unsigned char *addr = __bitops_byte(nr, ptr);
246 
247 	*addr |= 1 << (nr & 7);
248 }
249 
250 static inline void
251 __clear_bit(unsigned long nr, volatile unsigned long *ptr)
252 {
253 	unsigned char *addr = __bitops_byte(nr, ptr);
254 
255 	*addr &= ~(1 << (nr & 7));
256 }
257 
258 static inline void __change_bit(unsigned long nr, volatile unsigned long *ptr)
259 {
260 	unsigned char *addr = __bitops_byte(nr, ptr);
261 
262 	*addr ^= 1 << (nr & 7);
263 }
264 
265 static inline int
266 __test_and_set_bit(unsigned long nr, volatile unsigned long *ptr)
267 {
268 	unsigned char *addr = __bitops_byte(nr, ptr);
269 	unsigned char ch;
270 
271 	ch = *addr;
272 	*addr |= 1 << (nr & 7);
273 	return (ch >> (nr & 7)) & 1;
274 }
275 
276 static inline int
277 __test_and_clear_bit(unsigned long nr, volatile unsigned long *ptr)
278 {
279 	unsigned char *addr = __bitops_byte(nr, ptr);
280 	unsigned char ch;
281 
282 	ch = *addr;
283 	*addr &= ~(1 << (nr & 7));
284 	return (ch >> (nr & 7)) & 1;
285 }
286 
287 static inline int
288 __test_and_change_bit(unsigned long nr, volatile unsigned long *ptr)
289 {
290 	unsigned char *addr = __bitops_byte(nr, ptr);
291 	unsigned char ch;
292 
293 	ch = *addr;
294 	*addr ^= 1 << (nr & 7);
295 	return (ch >> (nr & 7)) & 1;
296 }
297 
298 static inline int test_bit(unsigned long nr, const volatile unsigned long *ptr)
299 {
300 	const volatile unsigned char *addr;
301 
302 	addr = ((const volatile unsigned char *)ptr);
303 	addr += (nr ^ (BITS_PER_LONG - 8)) >> 3;
304 	return (*addr >> (nr & 7)) & 1;
305 }
306 
307 /*
308  * Functions which use MSB0 bit numbering.
309  * On an s390x system the bits are numbered:
310  *   |0..............63|64............127|128...........191|192...........255|
311  * and on s390:
312  *   |0.....31|32....63|64....95|96...127|128..159|160..191|192..223|224..255|
313  */
314 unsigned long find_first_bit_inv(const unsigned long *addr, unsigned long size);
315 unsigned long find_next_bit_inv(const unsigned long *addr, unsigned long size,
316 				unsigned long offset);
317 
318 static inline void set_bit_inv(unsigned long nr, volatile unsigned long *ptr)
319 {
320 	return set_bit(nr ^ (BITS_PER_LONG - 1), ptr);
321 }
322 
323 static inline void clear_bit_inv(unsigned long nr, volatile unsigned long *ptr)
324 {
325 	return clear_bit(nr ^ (BITS_PER_LONG - 1), ptr);
326 }
327 
328 static inline void __set_bit_inv(unsigned long nr, volatile unsigned long *ptr)
329 {
330 	return __set_bit(nr ^ (BITS_PER_LONG - 1), ptr);
331 }
332 
333 static inline void __clear_bit_inv(unsigned long nr, volatile unsigned long *ptr)
334 {
335 	return __clear_bit(nr ^ (BITS_PER_LONG - 1), ptr);
336 }
337 
338 static inline int test_bit_inv(unsigned long nr,
339 			       const volatile unsigned long *ptr)
340 {
341 	return test_bit(nr ^ (BITS_PER_LONG - 1), ptr);
342 }
343 
344 #ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES
345 
346 /**
347  * __flogr - find leftmost one
348  * @word - The word to search
349  *
350  * Returns the bit number of the most significant bit set,
351  * where the most significant bit has bit number 0.
352  * If no bit is set this function returns 64.
353  */
354 static inline unsigned char __flogr(unsigned long word)
355 {
356 	if (__builtin_constant_p(word)) {
357 		unsigned long bit = 0;
358 
359 		if (!word)
360 			return 64;
361 		if (!(word & 0xffffffff00000000UL)) {
362 			word <<= 32;
363 			bit += 32;
364 		}
365 		if (!(word & 0xffff000000000000UL)) {
366 			word <<= 16;
367 			bit += 16;
368 		}
369 		if (!(word & 0xff00000000000000UL)) {
370 			word <<= 8;
371 			bit += 8;
372 		}
373 		if (!(word & 0xf000000000000000UL)) {
374 			word <<= 4;
375 			bit += 4;
376 		}
377 		if (!(word & 0xc000000000000000UL)) {
378 			word <<= 2;
379 			bit += 2;
380 		}
381 		if (!(word & 0x8000000000000000UL)) {
382 			word <<= 1;
383 			bit += 1;
384 		}
385 		return bit;
386 	} else {
387 		register unsigned long bit asm("4") = word;
388 		register unsigned long out asm("5");
389 
390 		asm volatile(
391 			"       flogr   %[bit],%[bit]\n"
392 			: [bit] "+d" (bit), [out] "=d" (out) : : "cc");
393 		return bit;
394 	}
395 }
396 
397 /**
398  * __ffs - find first bit in word.
399  * @word: The word to search
400  *
401  * Undefined if no bit exists, so code should check against 0 first.
402  */
403 static inline unsigned long __ffs(unsigned long word)
404 {
405 	return __flogr(-word & word) ^ (BITS_PER_LONG - 1);
406 }
407 
408 /**
409  * ffs - find first bit set
410  * @word: the word to search
411  *
412  * This is defined the same way as the libc and
413  * compiler builtin ffs routines (man ffs).
414  */
415 static inline int ffs(int word)
416 {
417 	unsigned long mask = 2 * BITS_PER_LONG - 1;
418 	unsigned int val = (unsigned int)word;
419 
420 	return (1 + (__flogr(-val & val) ^ (BITS_PER_LONG - 1))) & mask;
421 }
422 
423 /**
424  * __fls - find last (most-significant) set bit in a long word
425  * @word: the word to search
426  *
427  * Undefined if no set bit exists, so code should check against 0 first.
428  */
429 static inline unsigned long __fls(unsigned long word)
430 {
431 	return __flogr(word) ^ (BITS_PER_LONG - 1);
432 }
433 
434 /**
435  * fls64 - find last set bit in a 64-bit word
436  * @word: the word to search
437  *
438  * This is defined in a similar way as the libc and compiler builtin
439  * ffsll, but returns the position of the most significant set bit.
440  *
441  * fls64(value) returns 0 if value is 0 or the position of the last
442  * set bit if value is nonzero. The last (most significant) bit is
443  * at position 64.
444  */
445 static inline int fls64(unsigned long word)
446 {
447 	unsigned long mask = 2 * BITS_PER_LONG - 1;
448 
449 	return (1 + (__flogr(word) ^ (BITS_PER_LONG - 1))) & mask;
450 }
451 
452 /**
453  * fls - find last (most-significant) bit set
454  * @word: the word to search
455  *
456  * This is defined the same way as ffs.
457  * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
458  */
459 static inline int fls(int word)
460 {
461 	return fls64((unsigned int)word);
462 }
463 
464 #else /* CONFIG_HAVE_MARCH_Z9_109_FEATURES */
465 
466 #include <asm-generic/bitops/__ffs.h>
467 #include <asm-generic/bitops/ffs.h>
468 #include <asm-generic/bitops/__fls.h>
469 #include <asm-generic/bitops/fls.h>
470 #include <asm-generic/bitops/fls64.h>
471 
472 #endif /* CONFIG_HAVE_MARCH_Z9_109_FEATURES */
473 
474 #include <asm-generic/bitops/ffz.h>
475 #include <asm-generic/bitops/find.h>
476 #include <asm-generic/bitops/hweight.h>
477 #include <asm-generic/bitops/lock.h>
478 #include <asm-generic/bitops/sched.h>
479 #include <asm-generic/bitops/le.h>
480 #include <asm-generic/bitops/ext2-atomic-setbit.h>
481 
482 #endif /* _S390_BITOPS_H */
483