xref: /openbmc/linux/arch/s390/include/asm/bitops.h (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
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 #ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
55 
56 #define __BITOPS_OR		"laog"
57 #define __BITOPS_AND		"lang"
58 #define __BITOPS_XOR		"laxg"
59 #define __BITOPS_BARRIER	"bcr	14,0\n"
60 
61 #define __BITOPS_LOOP(__addr, __val, __op_string, __barrier)	\
62 ({								\
63 	unsigned long __old;					\
64 								\
65 	typecheck(unsigned long *, (__addr));			\
66 	asm volatile(						\
67 		__barrier					\
68 		__op_string "	%0,%2,%1\n"			\
69 		__barrier					\
70 		: "=d" (__old),	"+Q" (*(__addr))		\
71 		: "d" (__val)					\
72 		: "cc", "memory");				\
73 	__old;							\
74 })
75 
76 #else /* CONFIG_HAVE_MARCH_Z196_FEATURES */
77 
78 #define __BITOPS_OR		"ogr"
79 #define __BITOPS_AND		"ngr"
80 #define __BITOPS_XOR		"xgr"
81 #define __BITOPS_BARRIER	"\n"
82 
83 #define __BITOPS_LOOP(__addr, __val, __op_string, __barrier)	\
84 ({								\
85 	unsigned long __old, __new;				\
86 								\
87 	typecheck(unsigned long *, (__addr));			\
88 	asm volatile(						\
89 		"	lg	%0,%2\n"			\
90 		"0:	lgr	%1,%0\n"			\
91 		__op_string "	%1,%3\n"			\
92 		"	csg	%0,%1,%2\n"			\
93 		"	jl	0b"				\
94 		: "=&d" (__old), "=&d" (__new), "+Q" (*(__addr))\
95 		: "d" (__val)					\
96 		: "cc", "memory");				\
97 	__old;							\
98 })
99 
100 #endif /* CONFIG_HAVE_MARCH_Z196_FEATURES */
101 
102 #define __BITOPS_WORDS(bits) (((bits) + BITS_PER_LONG - 1) / BITS_PER_LONG)
103 
104 static inline unsigned long *
105 __bitops_word(unsigned long nr, volatile unsigned long *ptr)
106 {
107 	unsigned long addr;
108 
109 	addr = (unsigned long)ptr + ((nr ^ (nr & (BITS_PER_LONG - 1))) >> 3);
110 	return (unsigned long *)addr;
111 }
112 
113 static inline unsigned char *
114 __bitops_byte(unsigned long nr, volatile unsigned long *ptr)
115 {
116 	return ((unsigned char *)ptr) + ((nr ^ (BITS_PER_LONG - 8)) >> 3);
117 }
118 
119 static inline void set_bit(unsigned long nr, volatile unsigned long *ptr)
120 {
121 	unsigned long *addr = __bitops_word(nr, ptr);
122 	unsigned long mask;
123 
124 #ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES
125 	if (__builtin_constant_p(nr)) {
126 		unsigned char *caddr = __bitops_byte(nr, ptr);
127 
128 		asm volatile(
129 			"oi	%0,%b1\n"
130 			: "+Q" (*caddr)
131 			: "i" (1 << (nr & 7))
132 			: "cc", "memory");
133 		return;
134 	}
135 #endif
136 	mask = 1UL << (nr & (BITS_PER_LONG - 1));
137 	__BITOPS_LOOP(addr, mask, __BITOPS_OR, __BITOPS_NO_BARRIER);
138 }
139 
140 static inline void clear_bit(unsigned long nr, volatile unsigned long *ptr)
141 {
142 	unsigned long *addr = __bitops_word(nr, ptr);
143 	unsigned long mask;
144 
145 #ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES
146 	if (__builtin_constant_p(nr)) {
147 		unsigned char *caddr = __bitops_byte(nr, ptr);
148 
149 		asm volatile(
150 			"ni	%0,%b1\n"
151 			: "+Q" (*caddr)
152 			: "i" (~(1 << (nr & 7)))
153 			: "cc", "memory");
154 		return;
155 	}
156 #endif
157 	mask = ~(1UL << (nr & (BITS_PER_LONG - 1)));
158 	__BITOPS_LOOP(addr, mask, __BITOPS_AND, __BITOPS_NO_BARRIER);
159 }
160 
161 static inline void change_bit(unsigned long nr, volatile unsigned long *ptr)
162 {
163 	unsigned long *addr = __bitops_word(nr, ptr);
164 	unsigned long mask;
165 
166 #ifdef CONFIG_HAVE_MARCH_ZEC12_FEATURES
167 	if (__builtin_constant_p(nr)) {
168 		unsigned char *caddr = __bitops_byte(nr, ptr);
169 
170 		asm volatile(
171 			"xi	%0,%b1\n"
172 			: "+Q" (*caddr)
173 			: "i" (1 << (nr & 7))
174 			: "cc", "memory");
175 		return;
176 	}
177 #endif
178 	mask = 1UL << (nr & (BITS_PER_LONG - 1));
179 	__BITOPS_LOOP(addr, mask, __BITOPS_XOR, __BITOPS_NO_BARRIER);
180 }
181 
182 static inline int
183 test_and_set_bit(unsigned long nr, volatile unsigned long *ptr)
184 {
185 	unsigned long *addr = __bitops_word(nr, ptr);
186 	unsigned long old, mask;
187 
188 	mask = 1UL << (nr & (BITS_PER_LONG - 1));
189 	old = __BITOPS_LOOP(addr, mask, __BITOPS_OR, __BITOPS_BARRIER);
190 	return (old & mask) != 0;
191 }
192 
193 static inline int
194 test_and_clear_bit(unsigned long nr, volatile unsigned long *ptr)
195 {
196 	unsigned long *addr = __bitops_word(nr, ptr);
197 	unsigned long old, mask;
198 
199 	mask = ~(1UL << (nr & (BITS_PER_LONG - 1)));
200 	old = __BITOPS_LOOP(addr, mask, __BITOPS_AND, __BITOPS_BARRIER);
201 	return (old & ~mask) != 0;
202 }
203 
204 static inline int
205 test_and_change_bit(unsigned long nr, volatile unsigned long *ptr)
206 {
207 	unsigned long *addr = __bitops_word(nr, ptr);
208 	unsigned long old, mask;
209 
210 	mask = 1UL << (nr & (BITS_PER_LONG - 1));
211 	old = __BITOPS_LOOP(addr, mask, __BITOPS_XOR, __BITOPS_BARRIER);
212 	return (old & mask) != 0;
213 }
214 
215 static inline void __set_bit(unsigned long nr, volatile unsigned long *ptr)
216 {
217 	unsigned char *addr = __bitops_byte(nr, ptr);
218 
219 	*addr |= 1 << (nr & 7);
220 }
221 
222 static inline void
223 __clear_bit(unsigned long nr, volatile unsigned long *ptr)
224 {
225 	unsigned char *addr = __bitops_byte(nr, ptr);
226 
227 	*addr &= ~(1 << (nr & 7));
228 }
229 
230 static inline void __change_bit(unsigned long nr, volatile unsigned long *ptr)
231 {
232 	unsigned char *addr = __bitops_byte(nr, ptr);
233 
234 	*addr ^= 1 << (nr & 7);
235 }
236 
237 static inline int
238 __test_and_set_bit(unsigned long nr, volatile unsigned long *ptr)
239 {
240 	unsigned char *addr = __bitops_byte(nr, ptr);
241 	unsigned char ch;
242 
243 	ch = *addr;
244 	*addr |= 1 << (nr & 7);
245 	return (ch >> (nr & 7)) & 1;
246 }
247 
248 static inline int
249 __test_and_clear_bit(unsigned long nr, volatile unsigned long *ptr)
250 {
251 	unsigned char *addr = __bitops_byte(nr, ptr);
252 	unsigned char ch;
253 
254 	ch = *addr;
255 	*addr &= ~(1 << (nr & 7));
256 	return (ch >> (nr & 7)) & 1;
257 }
258 
259 static inline int
260 __test_and_change_bit(unsigned long nr, volatile unsigned long *ptr)
261 {
262 	unsigned char *addr = __bitops_byte(nr, ptr);
263 	unsigned char ch;
264 
265 	ch = *addr;
266 	*addr ^= 1 << (nr & 7);
267 	return (ch >> (nr & 7)) & 1;
268 }
269 
270 static inline int test_bit(unsigned long nr, const volatile unsigned long *ptr)
271 {
272 	const volatile unsigned char *addr;
273 
274 	addr = ((const volatile unsigned char *)ptr);
275 	addr += (nr ^ (BITS_PER_LONG - 8)) >> 3;
276 	return (*addr >> (nr & 7)) & 1;
277 }
278 
279 /*
280  * Functions which use MSB0 bit numbering.
281  * On an s390x system the bits are numbered:
282  *   |0..............63|64............127|128...........191|192...........255|
283  * and on s390:
284  *   |0.....31|32....63|64....95|96...127|128..159|160..191|192..223|224..255|
285  */
286 unsigned long find_first_bit_inv(const unsigned long *addr, unsigned long size);
287 unsigned long find_next_bit_inv(const unsigned long *addr, unsigned long size,
288 				unsigned long offset);
289 
290 static inline void set_bit_inv(unsigned long nr, volatile unsigned long *ptr)
291 {
292 	return set_bit(nr ^ (BITS_PER_LONG - 1), ptr);
293 }
294 
295 static inline void clear_bit_inv(unsigned long nr, volatile unsigned long *ptr)
296 {
297 	return clear_bit(nr ^ (BITS_PER_LONG - 1), ptr);
298 }
299 
300 static inline void __set_bit_inv(unsigned long nr, volatile unsigned long *ptr)
301 {
302 	return __set_bit(nr ^ (BITS_PER_LONG - 1), ptr);
303 }
304 
305 static inline void __clear_bit_inv(unsigned long nr, volatile unsigned long *ptr)
306 {
307 	return __clear_bit(nr ^ (BITS_PER_LONG - 1), ptr);
308 }
309 
310 static inline int test_bit_inv(unsigned long nr,
311 			       const volatile unsigned long *ptr)
312 {
313 	return test_bit(nr ^ (BITS_PER_LONG - 1), ptr);
314 }
315 
316 #ifdef CONFIG_HAVE_MARCH_Z9_109_FEATURES
317 
318 /**
319  * __flogr - find leftmost one
320  * @word - The word to search
321  *
322  * Returns the bit number of the most significant bit set,
323  * where the most significant bit has bit number 0.
324  * If no bit is set this function returns 64.
325  */
326 static inline unsigned char __flogr(unsigned long word)
327 {
328 	if (__builtin_constant_p(word)) {
329 		unsigned long bit = 0;
330 
331 		if (!word)
332 			return 64;
333 		if (!(word & 0xffffffff00000000UL)) {
334 			word <<= 32;
335 			bit += 32;
336 		}
337 		if (!(word & 0xffff000000000000UL)) {
338 			word <<= 16;
339 			bit += 16;
340 		}
341 		if (!(word & 0xff00000000000000UL)) {
342 			word <<= 8;
343 			bit += 8;
344 		}
345 		if (!(word & 0xf000000000000000UL)) {
346 			word <<= 4;
347 			bit += 4;
348 		}
349 		if (!(word & 0xc000000000000000UL)) {
350 			word <<= 2;
351 			bit += 2;
352 		}
353 		if (!(word & 0x8000000000000000UL)) {
354 			word <<= 1;
355 			bit += 1;
356 		}
357 		return bit;
358 	} else {
359 		register unsigned long bit asm("4") = word;
360 		register unsigned long out asm("5");
361 
362 		asm volatile(
363 			"       flogr   %[bit],%[bit]\n"
364 			: [bit] "+d" (bit), [out] "=d" (out) : : "cc");
365 		return bit;
366 	}
367 }
368 
369 /**
370  * __ffs - find first bit in word.
371  * @word: The word to search
372  *
373  * Undefined if no bit exists, so code should check against 0 first.
374  */
375 static inline unsigned long __ffs(unsigned long word)
376 {
377 	return __flogr(-word & word) ^ (BITS_PER_LONG - 1);
378 }
379 
380 /**
381  * ffs - find first bit set
382  * @word: the word to search
383  *
384  * This is defined the same way as the libc and
385  * compiler builtin ffs routines (man ffs).
386  */
387 static inline int ffs(int word)
388 {
389 	unsigned long mask = 2 * BITS_PER_LONG - 1;
390 	unsigned int val = (unsigned int)word;
391 
392 	return (1 + (__flogr(-val & val) ^ (BITS_PER_LONG - 1))) & mask;
393 }
394 
395 /**
396  * __fls - find last (most-significant) set bit in a long word
397  * @word: the word to search
398  *
399  * Undefined if no set bit exists, so code should check against 0 first.
400  */
401 static inline unsigned long __fls(unsigned long word)
402 {
403 	return __flogr(word) ^ (BITS_PER_LONG - 1);
404 }
405 
406 /**
407  * fls64 - find last set bit in a 64-bit word
408  * @word: the word to search
409  *
410  * This is defined in a similar way as the libc and compiler builtin
411  * ffsll, but returns the position of the most significant set bit.
412  *
413  * fls64(value) returns 0 if value is 0 or the position of the last
414  * set bit if value is nonzero. The last (most significant) bit is
415  * at position 64.
416  */
417 static inline int fls64(unsigned long word)
418 {
419 	unsigned long mask = 2 * BITS_PER_LONG - 1;
420 
421 	return (1 + (__flogr(word) ^ (BITS_PER_LONG - 1))) & mask;
422 }
423 
424 /**
425  * fls - find last (most-significant) bit set
426  * @word: the word to search
427  *
428  * This is defined the same way as ffs.
429  * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
430  */
431 static inline int fls(int word)
432 {
433 	return fls64((unsigned int)word);
434 }
435 
436 #else /* CONFIG_HAVE_MARCH_Z9_109_FEATURES */
437 
438 #include <asm-generic/bitops/__ffs.h>
439 #include <asm-generic/bitops/ffs.h>
440 #include <asm-generic/bitops/__fls.h>
441 #include <asm-generic/bitops/fls.h>
442 #include <asm-generic/bitops/fls64.h>
443 
444 #endif /* CONFIG_HAVE_MARCH_Z9_109_FEATURES */
445 
446 #include <asm-generic/bitops/ffz.h>
447 #include <asm-generic/bitops/find.h>
448 #include <asm-generic/bitops/hweight.h>
449 #include <asm-generic/bitops/lock.h>
450 #include <asm-generic/bitops/sched.h>
451 #include <asm-generic/bitops/le.h>
452 #include <asm-generic/bitops/ext2-atomic-setbit.h>
453 
454 #endif /* _S390_BITOPS_H */
455