1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
4 */
5
6 #ifndef _ASM_BITOPS_H
7 #define _ASM_BITOPS_H
8
9 #ifndef _LINUX_BITOPS_H
10 #error only <linux/bitops.h> can be included directly
11 #endif
12
13 #ifndef __ASSEMBLY__
14
15 #include <linux/types.h>
16 #include <linux/compiler.h>
17 #include <asm/barrier.h>
18 #ifndef CONFIG_ARC_HAS_LLSC
19 #include <asm/smp.h>
20 #endif
21
22 #ifdef CONFIG_ARC_HAS_LLSC
23
24 /*
25 * Hardware assisted Atomic-R-M-W
26 */
27
28 #define BIT_OP(op, c_op, asm_op) \
29 static inline void op##_bit(unsigned long nr, volatile unsigned long *m)\
30 { \
31 unsigned int temp; \
32 \
33 m += nr >> 5; \
34 \
35 nr &= 0x1f; \
36 \
37 __asm__ __volatile__( \
38 "1: llock %0, [%1] \n" \
39 " " #asm_op " %0, %0, %2 \n" \
40 " scond %0, [%1] \n" \
41 " bnz 1b \n" \
42 : "=&r"(temp) /* Early clobber, to prevent reg reuse */ \
43 : "r"(m), /* Not "m": llock only supports reg direct addr mode */ \
44 "ir"(nr) \
45 : "cc"); \
46 }
47
48 /*
49 * Semantically:
50 * Test the bit
51 * if clear
52 * set it and return 0 (old value)
53 * else
54 * return 1 (old value).
55 *
56 * Since ARC lacks a equivalent h/w primitive, the bit is set unconditionally
57 * and the old value of bit is returned
58 */
59 #define TEST_N_BIT_OP(op, c_op, asm_op) \
60 static inline int test_and_##op##_bit(unsigned long nr, volatile unsigned long *m)\
61 { \
62 unsigned long old, temp; \
63 \
64 m += nr >> 5; \
65 \
66 nr &= 0x1f; \
67 \
68 /* \
69 * Explicit full memory barrier needed before/after as \
70 * LLOCK/SCOND themselves don't provide any such smenatic \
71 */ \
72 smp_mb(); \
73 \
74 __asm__ __volatile__( \
75 "1: llock %0, [%2] \n" \
76 " " #asm_op " %1, %0, %3 \n" \
77 " scond %1, [%2] \n" \
78 " bnz 1b \n" \
79 : "=&r"(old), "=&r"(temp) \
80 : "r"(m), "ir"(nr) \
81 : "cc"); \
82 \
83 smp_mb(); \
84 \
85 return (old & (1 << nr)) != 0; \
86 }
87
88 #elif !defined(CONFIG_ARC_PLAT_EZNPS)
89
90 /*
91 * Non hardware assisted Atomic-R-M-W
92 * Locking would change to irq-disabling only (UP) and spinlocks (SMP)
93 *
94 * There's "significant" micro-optimization in writing our own variants of
95 * bitops (over generic variants)
96 *
97 * (1) The generic APIs have "signed" @nr while we have it "unsigned"
98 * This avoids extra code to be generated for pointer arithmatic, since
99 * is "not sure" that index is NOT -ve
100 * (2) Utilize the fact that ARCompact bit fidding insn (BSET/BCLR/ASL) etc
101 * only consider bottom 5 bits of @nr, so NO need to mask them off.
102 * (GCC Quirk: however for constant @nr we still need to do the masking
103 * at compile time)
104 */
105
106 #define BIT_OP(op, c_op, asm_op) \
107 static inline void op##_bit(unsigned long nr, volatile unsigned long *m)\
108 { \
109 unsigned long temp, flags; \
110 m += nr >> 5; \
111 \
112 /* \
113 * spin lock/unlock provide the needed smp_mb() before/after \
114 */ \
115 bitops_lock(flags); \
116 \
117 temp = *m; \
118 *m = temp c_op (1UL << (nr & 0x1f)); \
119 \
120 bitops_unlock(flags); \
121 }
122
123 #define TEST_N_BIT_OP(op, c_op, asm_op) \
124 static inline int test_and_##op##_bit(unsigned long nr, volatile unsigned long *m)\
125 { \
126 unsigned long old, flags; \
127 m += nr >> 5; \
128 \
129 bitops_lock(flags); \
130 \
131 old = *m; \
132 *m = old c_op (1UL << (nr & 0x1f)); \
133 \
134 bitops_unlock(flags); \
135 \
136 return (old & (1UL << (nr & 0x1f))) != 0; \
137 }
138
139 #else /* CONFIG_ARC_PLAT_EZNPS */
140
141 #define BIT_OP(op, c_op, asm_op) \
142 static inline void op##_bit(unsigned long nr, volatile unsigned long *m)\
143 { \
144 m += nr >> 5; \
145 \
146 nr = (1UL << (nr & 0x1f)); \
147 if (asm_op == CTOP_INST_AAND_DI_R2_R2_R3) \
148 nr = ~nr; \
149 \
150 __asm__ __volatile__( \
151 " mov r2, %0\n" \
152 " mov r3, %1\n" \
153 " .word %2\n" \
154 : \
155 : "r"(nr), "r"(m), "i"(asm_op) \
156 : "r2", "r3", "memory"); \
157 }
158
159 #define TEST_N_BIT_OP(op, c_op, asm_op) \
160 static inline int test_and_##op##_bit(unsigned long nr, volatile unsigned long *m)\
161 { \
162 unsigned long old; \
163 \
164 m += nr >> 5; \
165 \
166 nr = old = (1UL << (nr & 0x1f)); \
167 if (asm_op == CTOP_INST_AAND_DI_R2_R2_R3) \
168 old = ~old; \
169 \
170 /* Explicit full memory barrier needed before/after */ \
171 smp_mb(); \
172 \
173 __asm__ __volatile__( \
174 " mov r2, %0\n" \
175 " mov r3, %1\n" \
176 " .word %2\n" \
177 " mov %0, r2" \
178 : "+r"(old) \
179 : "r"(m), "i"(asm_op) \
180 : "r2", "r3", "memory"); \
181 \
182 smp_mb(); \
183 \
184 return (old & nr) != 0; \
185 }
186
187 #endif /* CONFIG_ARC_PLAT_EZNPS */
188
189 /***************************************
190 * Non atomic variants
191 **************************************/
192
193 #define __BIT_OP(op, c_op, asm_op) \
194 static inline void __##op##_bit(unsigned long nr, volatile unsigned long *m) \
195 { \
196 unsigned long temp; \
197 m += nr >> 5; \
198 \
199 temp = *m; \
200 *m = temp c_op (1UL << (nr & 0x1f)); \
201 }
202
203 #define __TEST_N_BIT_OP(op, c_op, asm_op) \
204 static inline int __test_and_##op##_bit(unsigned long nr, volatile unsigned long *m)\
205 { \
206 unsigned long old; \
207 m += nr >> 5; \
208 \
209 old = *m; \
210 *m = old c_op (1UL << (nr & 0x1f)); \
211 \
212 return (old & (1UL << (nr & 0x1f))) != 0; \
213 }
214
215 #define BIT_OPS(op, c_op, asm_op) \
216 \
217 /* set_bit(), clear_bit(), change_bit() */ \
218 BIT_OP(op, c_op, asm_op) \
219 \
220 /* test_and_set_bit(), test_and_clear_bit(), test_and_change_bit() */\
221 TEST_N_BIT_OP(op, c_op, asm_op) \
222 \
223 /* __set_bit(), __clear_bit(), __change_bit() */ \
224 __BIT_OP(op, c_op, asm_op) \
225 \
226 /* __test_and_set_bit(), __test_and_clear_bit(), __test_and_change_bit() */\
227 __TEST_N_BIT_OP(op, c_op, asm_op)
228
229 #ifndef CONFIG_ARC_PLAT_EZNPS
230 BIT_OPS(set, |, bset)
231 BIT_OPS(clear, & ~, bclr)
232 BIT_OPS(change, ^, bxor)
233 #else
234 BIT_OPS(set, |, CTOP_INST_AOR_DI_R2_R2_R3)
235 BIT_OPS(clear, & ~, CTOP_INST_AAND_DI_R2_R2_R3)
236 BIT_OPS(change, ^, CTOP_INST_AXOR_DI_R2_R2_R3)
237 #endif
238
239 /*
240 * This routine doesn't need to be atomic.
241 */
242 static inline int
243 test_bit(unsigned int nr, const volatile unsigned long *addr)
244 {
245 unsigned long mask;
246
247 addr += nr >> 5;
248
249 mask = 1UL << (nr & 0x1f);
250
251 return ((mask & *addr) != 0);
252 }
253
254 #ifdef CONFIG_ISA_ARCOMPACT
255
256 /*
257 * Count the number of zeros, starting from MSB
258 * Helper for fls( ) friends
259 * This is a pure count, so (1-32) or (0-31) doesn't apply
260 * It could be 0 to 32, based on num of 0's in there
261 * clz(0x8000_0000) = 0, clz(0xFFFF_FFFF)=0, clz(0) = 32, clz(1) = 31
262 */
263 static inline __attribute__ ((const)) int clz(unsigned int x)
264 {
265 unsigned int res;
266
267 __asm__ __volatile__(
268 " norm.f %0, %1 \n"
269 " mov.n %0, 0 \n"
270 " add.p %0, %0, 1 \n"
271 : "=r"(res)
272 : "r"(x)
273 : "cc");
274
275 return res;
276 }
277
278 static inline int constant_fls(unsigned int x)
279 {
280 int r = 32;
281
282 if (!x)
283 return 0;
284 if (!(x & 0xffff0000u)) {
285 x <<= 16;
286 r -= 16;
287 }
288 if (!(x & 0xff000000u)) {
289 x <<= 8;
290 r -= 8;
291 }
292 if (!(x & 0xf0000000u)) {
293 x <<= 4;
294 r -= 4;
295 }
296 if (!(x & 0xc0000000u)) {
297 x <<= 2;
298 r -= 2;
299 }
300 if (!(x & 0x80000000u)) {
301 x <<= 1;
302 r -= 1;
303 }
304 return r;
305 }
306
307 /*
308 * fls = Find Last Set in word
309 * @result: [1-32]
310 * fls(1) = 1, fls(0x80000000) = 32, fls(0) = 0
311 */
312 static inline __attribute__ ((const)) int fls(unsigned int x)
313 {
314 if (__builtin_constant_p(x))
315 return constant_fls(x);
316
317 return 32 - clz(x);
318 }
319
320 /*
321 * __fls: Similar to fls, but zero based (0-31)
322 */
323 static inline __attribute__ ((const)) int __fls(unsigned long x)
324 {
325 if (!x)
326 return 0;
327 else
328 return fls(x) - 1;
329 }
330
331 /*
332 * ffs = Find First Set in word (LSB to MSB)
333 * @result: [1-32], 0 if all 0's
334 */
335 #define ffs(x) ({ unsigned long __t = (x); fls(__t & -__t); })
336
337 /*
338 * __ffs: Similar to ffs, but zero based (0-31)
339 */
340 static inline __attribute__ ((const)) unsigned long __ffs(unsigned long word)
341 {
342 if (!word)
343 return word;
344
345 return ffs(word) - 1;
346 }
347
348 #else /* CONFIG_ISA_ARCV2 */
349
350 /*
351 * fls = Find Last Set in word
352 * @result: [1-32]
353 * fls(1) = 1, fls(0x80000000) = 32, fls(0) = 0
354 */
355 static inline __attribute__ ((const)) int fls(unsigned long x)
356 {
357 int n;
358
359 asm volatile(
360 " fls.f %0, %1 \n" /* 0:31; 0(Z) if src 0 */
361 " add.nz %0, %0, 1 \n" /* 0:31 -> 1:32 */
362 : "=r"(n) /* Early clobber not needed */
363 : "r"(x)
364 : "cc");
365
366 return n;
367 }
368
369 /*
370 * __fls: Similar to fls, but zero based (0-31). Also 0 if no bit set
371 */
372 static inline __attribute__ ((const)) int __fls(unsigned long x)
373 {
374 /* FLS insn has exactly same semantics as the API */
375 return __builtin_arc_fls(x);
376 }
377
378 /*
379 * ffs = Find First Set in word (LSB to MSB)
380 * @result: [1-32], 0 if all 0's
381 */
382 static inline __attribute__ ((const)) int ffs(unsigned long x)
383 {
384 int n;
385
386 asm volatile(
387 " ffs.f %0, %1 \n" /* 0:31; 31(Z) if src 0 */
388 " add.nz %0, %0, 1 \n" /* 0:31 -> 1:32 */
389 " mov.z %0, 0 \n" /* 31(Z)-> 0 */
390 : "=r"(n) /* Early clobber not needed */
391 : "r"(x)
392 : "cc");
393
394 return n;
395 }
396
397 /*
398 * __ffs: Similar to ffs, but zero based (0-31)
399 */
400 static inline __attribute__ ((const)) unsigned long __ffs(unsigned long x)
401 {
402 unsigned long n;
403
404 asm volatile(
405 " ffs.f %0, %1 \n" /* 0:31; 31(Z) if src 0 */
406 " mov.z %0, 0 \n" /* 31(Z)-> 0 */
407 : "=r"(n)
408 : "r"(x)
409 : "cc");
410
411 return n;
412
413 }
414
415 #endif /* CONFIG_ISA_ARCOMPACT */
416
417 /*
418 * ffz = Find First Zero in word.
419 * @return:[0-31], 32 if all 1's
420 */
421 #define ffz(x) __ffs(~(x))
422
423 #include <asm-generic/bitops/hweight.h>
424 #include <asm-generic/bitops/fls64.h>
425 #include <asm-generic/bitops/sched.h>
426 #include <asm-generic/bitops/lock.h>
427
428 #include <asm-generic/bitops/find.h>
429 #include <asm-generic/bitops/le.h>
430 #include <asm-generic/bitops/ext2-atomic-setbit.h>
431
432 #endif /* !__ASSEMBLY__ */
433
434 #endif