Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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kernel
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linux
1/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 1994, 95, 96, 97, 98, 99, 2003, 06 by Ralf Baechle
7 * Copyright (C) 1996 by Paul M. Antoine
8 * Copyright (C) 1999 Silicon Graphics
9 * Kevin D. Kissell, kevink@mips.org and Carsten Langgaard, carstenl@mips.com
10 * Copyright (C) 2000 MIPS Technologies, Inc.
11 */
12#ifndef _ASM_SYSTEM_H
13#define _ASM_SYSTEM_H
14
15#include <linux/types.h>
16#include <linux/irqflags.h>
17
18#include <asm/addrspace.h>
19#include <asm/barrier.h>
20#include <asm/cpu-features.h>
21#include <asm/dsp.h>
22#include <asm/war.h>
23
24
25/*
26 * switch_to(n) should switch tasks to task nr n, first
27 * checking that n isn't the current task, in which case it does nothing.
28 */
29extern asmlinkage void *resume(void *last, void *next, void *next_ti);
30
31struct task_struct;
32
33#ifdef CONFIG_MIPS_MT_FPAFF
34
35/*
36 * Handle the scheduler resume end of FPU affinity management. We do this
37 * inline to try to keep the overhead down. If we have been forced to run on
38 * a "CPU" with an FPU because of a previous high level of FP computation,
39 * but did not actually use the FPU during the most recent time-slice (CU1
40 * isn't set), we undo the restriction on cpus_allowed.
41 *
42 * We're not calling set_cpus_allowed() here, because we have no need to
43 * force prompt migration - we're already switching the current CPU to a
44 * different thread.
45 */
46
47#define __mips_mt_fpaff_switch_to(prev) \
48do { \
49 struct thread_info *__prev_ti = task_thread_info(prev); \
50 \
51 if (cpu_has_fpu && \
52 test_ti_thread_flag(__prev_ti, TIF_FPUBOUND) && \
53 (!(KSTK_STATUS(prev) & ST0_CU1))) { \
54 clear_ti_thread_flag(__prev_ti, TIF_FPUBOUND); \
55 prev->cpus_allowed = prev->thread.user_cpus_allowed; \
56 } \
57 next->thread.emulated_fp = 0; \
58} while(0)
59
60#else
61#define __mips_mt_fpaff_switch_to(prev) do { (void) (prev); } while (0)
62#endif
63
64#define switch_to(prev,next,last) \
65do { \
66 __mips_mt_fpaff_switch_to(prev); \
67 if (cpu_has_dsp) \
68 __save_dsp(prev); \
69 (last) = resume(prev, next, task_thread_info(next)); \
70 if (cpu_has_dsp) \
71 __restore_dsp(current); \
72 if (cpu_has_userlocal) \
73 write_c0_userlocal(task_thread_info(current)->tp_value);\
74} while(0)
75
76static inline unsigned long __xchg_u32(volatile int * m, unsigned int val)
77{
78 __u32 retval;
79
80 if (cpu_has_llsc && R10000_LLSC_WAR) {
81 unsigned long dummy;
82
83 __asm__ __volatile__(
84 " .set mips3 \n"
85 "1: ll %0, %3 # xchg_u32 \n"
86 " .set mips0 \n"
87 " move %2, %z4 \n"
88 " .set mips3 \n"
89 " sc %2, %1 \n"
90 " beqzl %2, 1b \n"
91 " .set mips0 \n"
92 : "=&r" (retval), "=m" (*m), "=&r" (dummy)
93 : "R" (*m), "Jr" (val)
94 : "memory");
95 } else if (cpu_has_llsc) {
96 unsigned long dummy;
97
98 __asm__ __volatile__(
99 " .set mips3 \n"
100 "1: ll %0, %3 # xchg_u32 \n"
101 " .set mips0 \n"
102 " move %2, %z4 \n"
103 " .set mips3 \n"
104 " sc %2, %1 \n"
105 " beqz %2, 2f \n"
106 " .subsection 2 \n"
107 "2: b 1b \n"
108 " .previous \n"
109 " .set mips0 \n"
110 : "=&r" (retval), "=m" (*m), "=&r" (dummy)
111 : "R" (*m), "Jr" (val)
112 : "memory");
113 } else {
114 unsigned long flags;
115
116 raw_local_irq_save(flags);
117 retval = *m;
118 *m = val;
119 raw_local_irq_restore(flags); /* implies memory barrier */
120 }
121
122 smp_llsc_mb();
123
124 return retval;
125}
126
127#ifdef CONFIG_64BIT
128static inline __u64 __xchg_u64(volatile __u64 * m, __u64 val)
129{
130 __u64 retval;
131
132 if (cpu_has_llsc && R10000_LLSC_WAR) {
133 unsigned long dummy;
134
135 __asm__ __volatile__(
136 " .set mips3 \n"
137 "1: lld %0, %3 # xchg_u64 \n"
138 " move %2, %z4 \n"
139 " scd %2, %1 \n"
140 " beqzl %2, 1b \n"
141 " .set mips0 \n"
142 : "=&r" (retval), "=m" (*m), "=&r" (dummy)
143 : "R" (*m), "Jr" (val)
144 : "memory");
145 } else if (cpu_has_llsc) {
146 unsigned long dummy;
147
148 __asm__ __volatile__(
149 " .set mips3 \n"
150 "1: lld %0, %3 # xchg_u64 \n"
151 " move %2, %z4 \n"
152 " scd %2, %1 \n"
153 " beqz %2, 2f \n"
154 " .subsection 2 \n"
155 "2: b 1b \n"
156 " .previous \n"
157 " .set mips0 \n"
158 : "=&r" (retval), "=m" (*m), "=&r" (dummy)
159 : "R" (*m), "Jr" (val)
160 : "memory");
161 } else {
162 unsigned long flags;
163
164 raw_local_irq_save(flags);
165 retval = *m;
166 *m = val;
167 raw_local_irq_restore(flags); /* implies memory barrier */
168 }
169
170 smp_llsc_mb();
171
172 return retval;
173}
174#else
175extern __u64 __xchg_u64_unsupported_on_32bit_kernels(volatile __u64 * m, __u64 val);
176#define __xchg_u64 __xchg_u64_unsupported_on_32bit_kernels
177#endif
178
179/* This function doesn't exist, so you'll get a linker error
180 if something tries to do an invalid xchg(). */
181extern void __xchg_called_with_bad_pointer(void);
182
183static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size)
184{
185 switch (size) {
186 case 4:
187 return __xchg_u32(ptr, x);
188 case 8:
189 return __xchg_u64(ptr, x);
190 }
191 __xchg_called_with_bad_pointer();
192 return x;
193}
194
195#define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
196
197#define __HAVE_ARCH_CMPXCHG 1
198
199static inline unsigned long __cmpxchg_u32(volatile int * m, unsigned long old,
200 unsigned long new)
201{
202 __u32 retval;
203
204 if (cpu_has_llsc && R10000_LLSC_WAR) {
205 __asm__ __volatile__(
206 " .set push \n"
207 " .set noat \n"
208 " .set mips3 \n"
209 "1: ll %0, %2 # __cmpxchg_u32 \n"
210 " bne %0, %z3, 2f \n"
211 " .set mips0 \n"
212 " move $1, %z4 \n"
213 " .set mips3 \n"
214 " sc $1, %1 \n"
215 " beqzl $1, 1b \n"
216 "2: \n"
217 " .set pop \n"
218 : "=&r" (retval), "=R" (*m)
219 : "R" (*m), "Jr" (old), "Jr" (new)
220 : "memory");
221 } else if (cpu_has_llsc) {
222 __asm__ __volatile__(
223 " .set push \n"
224 " .set noat \n"
225 " .set mips3 \n"
226 "1: ll %0, %2 # __cmpxchg_u32 \n"
227 " bne %0, %z3, 2f \n"
228 " .set mips0 \n"
229 " move $1, %z4 \n"
230 " .set mips3 \n"
231 " sc $1, %1 \n"
232 " beqz $1, 3f \n"
233 "2: \n"
234 " .subsection 2 \n"
235 "3: b 1b \n"
236 " .previous \n"
237 " .set pop \n"
238 : "=&r" (retval), "=R" (*m)
239 : "R" (*m), "Jr" (old), "Jr" (new)
240 : "memory");
241 } else {
242 unsigned long flags;
243
244 raw_local_irq_save(flags);
245 retval = *m;
246 if (retval == old)
247 *m = new;
248 raw_local_irq_restore(flags); /* implies memory barrier */
249 }
250
251 smp_llsc_mb();
252
253 return retval;
254}
255
256static inline unsigned long __cmpxchg_u32_local(volatile int * m,
257 unsigned long old, unsigned long new)
258{
259 __u32 retval;
260
261 if (cpu_has_llsc && R10000_LLSC_WAR) {
262 __asm__ __volatile__(
263 " .set push \n"
264 " .set noat \n"
265 " .set mips3 \n"
266 "1: ll %0, %2 # __cmpxchg_u32 \n"
267 " bne %0, %z3, 2f \n"
268 " .set mips0 \n"
269 " move $1, %z4 \n"
270 " .set mips3 \n"
271 " sc $1, %1 \n"
272 " beqzl $1, 1b \n"
273 "2: \n"
274 " .set pop \n"
275 : "=&r" (retval), "=R" (*m)
276 : "R" (*m), "Jr" (old), "Jr" (new)
277 : "memory");
278 } else if (cpu_has_llsc) {
279 __asm__ __volatile__(
280 " .set push \n"
281 " .set noat \n"
282 " .set mips3 \n"
283 "1: ll %0, %2 # __cmpxchg_u32 \n"
284 " bne %0, %z3, 2f \n"
285 " .set mips0 \n"
286 " move $1, %z4 \n"
287 " .set mips3 \n"
288 " sc $1, %1 \n"
289 " beqz $1, 1b \n"
290 "2: \n"
291 " .set pop \n"
292 : "=&r" (retval), "=R" (*m)
293 : "R" (*m), "Jr" (old), "Jr" (new)
294 : "memory");
295 } else {
296 unsigned long flags;
297
298 local_irq_save(flags);
299 retval = *m;
300 if (retval == old)
301 *m = new;
302 local_irq_restore(flags); /* implies memory barrier */
303 }
304
305 return retval;
306}
307
308#ifdef CONFIG_64BIT
309static inline unsigned long __cmpxchg_u64(volatile int * m, unsigned long old,
310 unsigned long new)
311{
312 __u64 retval;
313
314 if (cpu_has_llsc && R10000_LLSC_WAR) {
315 __asm__ __volatile__(
316 " .set push \n"
317 " .set noat \n"
318 " .set mips3 \n"
319 "1: lld %0, %2 # __cmpxchg_u64 \n"
320 " bne %0, %z3, 2f \n"
321 " move $1, %z4 \n"
322 " scd $1, %1 \n"
323 " beqzl $1, 1b \n"
324 "2: \n"
325 " .set pop \n"
326 : "=&r" (retval), "=R" (*m)
327 : "R" (*m), "Jr" (old), "Jr" (new)
328 : "memory");
329 } else if (cpu_has_llsc) {
330 __asm__ __volatile__(
331 " .set push \n"
332 " .set noat \n"
333 " .set mips3 \n"
334 "1: lld %0, %2 # __cmpxchg_u64 \n"
335 " bne %0, %z3, 2f \n"
336 " move $1, %z4 \n"
337 " scd $1, %1 \n"
338 " beqz $1, 3f \n"
339 "2: \n"
340 " .subsection 2 \n"
341 "3: b 1b \n"
342 " .previous \n"
343 " .set pop \n"
344 : "=&r" (retval), "=R" (*m)
345 : "R" (*m), "Jr" (old), "Jr" (new)
346 : "memory");
347 } else {
348 unsigned long flags;
349
350 raw_local_irq_save(flags);
351 retval = *m;
352 if (retval == old)
353 *m = new;
354 raw_local_irq_restore(flags); /* implies memory barrier */
355 }
356
357 smp_llsc_mb();
358
359 return retval;
360}
361
362static inline unsigned long __cmpxchg_u64_local(volatile int * m,
363 unsigned long old, unsigned long new)
364{
365 __u64 retval;
366
367 if (cpu_has_llsc && R10000_LLSC_WAR) {
368 __asm__ __volatile__(
369 " .set push \n"
370 " .set noat \n"
371 " .set mips3 \n"
372 "1: lld %0, %2 # __cmpxchg_u64 \n"
373 " bne %0, %z3, 2f \n"
374 " move $1, %z4 \n"
375 " scd $1, %1 \n"
376 " beqzl $1, 1b \n"
377 "2: \n"
378 " .set pop \n"
379 : "=&r" (retval), "=R" (*m)
380 : "R" (*m), "Jr" (old), "Jr" (new)
381 : "memory");
382 } else if (cpu_has_llsc) {
383 __asm__ __volatile__(
384 " .set push \n"
385 " .set noat \n"
386 " .set mips3 \n"
387 "1: lld %0, %2 # __cmpxchg_u64 \n"
388 " bne %0, %z3, 2f \n"
389 " move $1, %z4 \n"
390 " scd $1, %1 \n"
391 " beqz $1, 1b \n"
392 "2: \n"
393 " .set pop \n"
394 : "=&r" (retval), "=R" (*m)
395 : "R" (*m), "Jr" (old), "Jr" (new)
396 : "memory");
397 } else {
398 unsigned long flags;
399
400 local_irq_save(flags);
401 retval = *m;
402 if (retval == old)
403 *m = new;
404 local_irq_restore(flags); /* implies memory barrier */
405 }
406
407 return retval;
408}
409
410#else
411extern unsigned long __cmpxchg_u64_unsupported_on_32bit_kernels(
412 volatile int * m, unsigned long old, unsigned long new);
413#define __cmpxchg_u64 __cmpxchg_u64_unsupported_on_32bit_kernels
414extern unsigned long __cmpxchg_u64_local_unsupported_on_32bit_kernels(
415 volatile int * m, unsigned long old, unsigned long new);
416#define __cmpxchg_u64_local __cmpxchg_u64_local_unsupported_on_32bit_kernels
417#endif
418
419/* This function doesn't exist, so you'll get a linker error
420 if something tries to do an invalid cmpxchg(). */
421extern void __cmpxchg_called_with_bad_pointer(void);
422
423static inline unsigned long __cmpxchg(volatile void * ptr, unsigned long old,
424 unsigned long new, int size)
425{
426 switch (size) {
427 case 4:
428 return __cmpxchg_u32(ptr, old, new);
429 case 8:
430 return __cmpxchg_u64(ptr, old, new);
431 }
432 __cmpxchg_called_with_bad_pointer();
433 return old;
434}
435
436static inline unsigned long __cmpxchg_local(volatile void * ptr,
437 unsigned long old, unsigned long new, int size)
438{
439 switch (size) {
440 case 4:
441 return __cmpxchg_u32_local(ptr, old, new);
442 case 8:
443 return __cmpxchg_u64_local(ptr, old, new);
444 }
445 __cmpxchg_called_with_bad_pointer();
446 return old;
447}
448
449#define cmpxchg(ptr,old,new) \
450 ((__typeof__(*(ptr)))__cmpxchg((ptr), \
451 (unsigned long)(old), (unsigned long)(new),sizeof(*(ptr))))
452
453#define cmpxchg_local(ptr,old,new) \
454 ((__typeof__(*(ptr)))__cmpxchg_local((ptr), \
455 (unsigned long)(old), (unsigned long)(new),sizeof(*(ptr))))
456
457extern void set_handler (unsigned long offset, void *addr, unsigned long len);
458extern void set_uncached_handler (unsigned long offset, void *addr, unsigned long len);
459
460typedef void (*vi_handler_t)(void);
461extern void *set_vi_handler (int n, vi_handler_t addr);
462
463extern void *set_except_vector(int n, void *addr);
464extern unsigned long ebase;
465extern void per_cpu_trap_init(void);
466
467extern int stop_a_enabled;
468
469/*
470 * See include/asm-ia64/system.h; prevents deadlock on SMP
471 * systems.
472 */
473#define __ARCH_WANT_UNLOCKED_CTXSW
474
475extern unsigned long arch_align_stack(unsigned long sp);
476
477#endif /* _ASM_SYSTEM_H */