1 #ifndef __ASM_ARM_SYSTEM_H
2 #define __ASM_ARM_SYSTEM_H
3
4 #ifdef __KERNEL__
5
6 #define CPU_ARCH_UNKNOWN 0
7 #define CPU_ARCH_ARMv3 1
8 #define CPU_ARCH_ARMv4 2
9 #define CPU_ARCH_ARMv4T 3
10 #define CPU_ARCH_ARMv5 4
11 #define CPU_ARCH_ARMv5T 5
12 #define CPU_ARCH_ARMv5TE 6
13 #define CPU_ARCH_ARMv5TEJ 7
14 #define CPU_ARCH_ARMv6 8
15 #define CPU_ARCH_ARMv7 9
16
17 /*
18 * CR1 bits (CP#15 CR1)
19 */
20 #define CR_M (1 << 0) /* MMU enable */
21 #define CR_A (1 << 1) /* Alignment abort enable */
22 #define CR_C (1 << 2) /* Dcache enable */
23 #define CR_W (1 << 3) /* Write buffer enable */
24 #define CR_P (1 << 4) /* 32-bit exception handler */
25 #define CR_D (1 << 5) /* 32-bit data address range */
26 #define CR_L (1 << 6) /* Implementation defined */
27 #define CR_B (1 << 7) /* Big endian */
28 #define CR_S (1 << 8) /* System MMU protection */
29 #define CR_R (1 << 9) /* ROM MMU protection */
30 #define CR_F (1 << 10) /* Implementation defined */
31 #define CR_Z (1 << 11) /* Implementation defined */
32 #define CR_I (1 << 12) /* Icache enable */
33 #define CR_V (1 << 13) /* Vectors relocated to 0xffff0000 */
34 #define CR_RR (1 << 14) /* Round Robin cache replacement */
35 #define CR_L4 (1 << 15) /* LDR pc can set T bit */
36 #define CR_DT (1 << 16)
37 #define CR_IT (1 << 18)
38 #define CR_ST (1 << 19)
39 #define CR_FI (1 << 21) /* Fast interrupt (lower latency mode) */
40 #define CR_U (1 << 22) /* Unaligned access operation */
41 #define CR_XP (1 << 23) /* Extended page tables */
42 #define CR_VE (1 << 24) /* Vectored interrupts */
43 #define CR_EE (1 << 25) /* Exception (Big) Endian */
44 #define CR_TRE (1 << 28) /* TEX remap enable */
45 #define CR_AFE (1 << 29) /* Access flag enable */
46 #define CR_TE (1 << 30) /* Thumb exception enable */
47
48 /*
49 * This is used to ensure the compiler did actually allocate the register we
50 * asked it for some inline assembly sequences. Apparently we can't trust
51 * the compiler from one version to another so a bit of paranoia won't hurt.
52 * This string is meant to be concatenated with the inline asm string and
53 * will cause compilation to stop on mismatch.
54 * (for details, see gcc PR 15089)
55 */
56 #define __asmeq(x, y) ".ifnc " x "," y " ; .err ; .endif\n\t"
57
58 #ifndef __ASSEMBLY__
59
60 #include <linux/linkage.h>
61 #include <linux/irqflags.h>
62
63 #include <asm/outercache.h>
64
65 #define __exception __attribute__((section(".exception.text")))
66 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
67 #define __exception_irq_entry __irq_entry
68 #else
69 #define __exception_irq_entry __exception
70 #endif
71
72 struct thread_info;
73 struct task_struct;
74
75 /* information about the system we're running on */
76 extern unsigned int system_rev;
77 extern unsigned int system_serial_low;
78 extern unsigned int system_serial_high;
79 extern unsigned int mem_fclk_21285;
80
81 struct pt_regs;
82
83 void die(const char *msg, struct pt_regs *regs, int err);
84
85 struct siginfo;
86 void arm_notify_die(const char *str, struct pt_regs *regs, struct siginfo *info,
87 unsigned long err, unsigned long trap);
88
89 void hook_fault_code(int nr, int (*fn)(unsigned long, unsigned int,
90 struct pt_regs *),
91 int sig, int code, const char *name);
92
93 void hook_ifault_code(int nr, int (*fn)(unsigned long, unsigned int,
94 struct pt_regs *),
95 int sig, int code, const char *name);
96
97 #define xchg(ptr,x) \
98 ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
99
100 extern asmlinkage void __backtrace(void);
101 extern asmlinkage void c_backtrace(unsigned long fp, int pmode);
102
103 struct mm_struct;
104 extern void show_pte(struct mm_struct *mm, unsigned long addr);
105 extern void __show_regs(struct pt_regs *);
106
107 extern int cpu_architecture(void);
108 extern void cpu_init(void);
109
110 void arm_machine_restart(char mode, const char *cmd);
111 extern void (*arm_pm_restart)(char str, const char *cmd);
112
113 #define UDBG_UNDEFINED (1 << 0)
114 #define UDBG_SYSCALL (1 << 1)
115 #define UDBG_BADABORT (1 << 2)
116 #define UDBG_SEGV (1 << 3)
117 #define UDBG_BUS (1 << 4)
118
119 extern unsigned int user_debug;
120
121 #if __LINUX_ARM_ARCH__ >= 4
122 #define vectors_high() (cr_alignment & CR_V)
123 #else
124 #define vectors_high() (0)
125 #endif
126
127 #if __LINUX_ARM_ARCH__ >= 7 || \
128 (__LINUX_ARM_ARCH__ == 6 && defined(CONFIG_CPU_32v6K))
129 #define sev() __asm__ __volatile__ ("sev" : : : "memory")
130 #define wfe() __asm__ __volatile__ ("wfe" : : : "memory")
131 #define wfi() __asm__ __volatile__ ("wfi" : : : "memory")
132 #endif
133
134 #if __LINUX_ARM_ARCH__ >= 7
135 #define isb() __asm__ __volatile__ ("isb" : : : "memory")
136 #define dsb() __asm__ __volatile__ ("dsb" : : : "memory")
137 #define dmb() __asm__ __volatile__ ("dmb" : : : "memory")
138 #elif defined(CONFIG_CPU_XSC3) || __LINUX_ARM_ARCH__ == 6
139 #define isb() __asm__ __volatile__ ("mcr p15, 0, %0, c7, c5, 4" \
140 : : "r" (0) : "memory")
141 #define dsb() __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 4" \
142 : : "r" (0) : "memory")
143 #define dmb() __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 5" \
144 : : "r" (0) : "memory")
145 #elif defined(CONFIG_CPU_FA526)
146 #define isb() __asm__ __volatile__ ("mcr p15, 0, %0, c7, c5, 4" \
147 : : "r" (0) : "memory")
148 #define dsb() __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 4" \
149 : : "r" (0) : "memory")
150 #define dmb() __asm__ __volatile__ ("" : : : "memory")
151 #else
152 #define isb() __asm__ __volatile__ ("" : : : "memory")
153 #define dsb() __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 4" \
154 : : "r" (0) : "memory")
155 #define dmb() __asm__ __volatile__ ("" : : : "memory")
156 #endif
157
158 #ifdef CONFIG_ARCH_HAS_BARRIERS
159 #include <mach/barriers.h>
160 #elif defined(CONFIG_ARM_DMA_MEM_BUFFERABLE) || defined(CONFIG_SMP)
161 #define mb() do { dsb(); outer_sync(); } while (0)
162 #define rmb() dsb()
163 #define wmb() mb()
164 #else
165 #include <asm/memory.h>
166 #define mb() do { if (arch_is_coherent()) dmb(); else barrier(); } while (0)
167 #define rmb() do { if (arch_is_coherent()) dmb(); else barrier(); } while (0)
168 #define wmb() do { if (arch_is_coherent()) dmb(); else barrier(); } while (0)
169 #endif
170
171 #ifndef CONFIG_SMP
172 #define smp_mb() barrier()
173 #define smp_rmb() barrier()
174 #define smp_wmb() barrier()
175 #else
176 #define smp_mb() dmb()
177 #define smp_rmb() dmb()
178 #define smp_wmb() dmb()
179 #endif
180
181 #define read_barrier_depends() do { } while(0)
182 #define smp_read_barrier_depends() do { } while(0)
183
184 #define set_mb(var, value) do { var = value; smp_mb(); } while (0)
185 #define nop() __asm__ __volatile__("mov\tr0,r0\t@ nop\n\t");
186
187 extern unsigned long cr_no_alignment; /* defined in entry-armv.S */
188 extern unsigned long cr_alignment; /* defined in entry-armv.S */
189
get_cr(void)190 static inline unsigned int get_cr(void)
191 {
192 unsigned int val;
193 asm("mrc p15, 0, %0, c1, c0, 0 @ get CR" : "=r" (val) : : "cc");
194 return val;
195 }
196
set_cr(unsigned int val)197 static inline void set_cr(unsigned int val)
198 {
199 asm volatile("mcr p15, 0, %0, c1, c0, 0 @ set CR"
200 : : "r" (val) : "cc");
201 isb();
202 }
203
204 #ifndef CONFIG_SMP
205 extern void adjust_cr(unsigned long mask, unsigned long set);
206 #endif
207
208 #define CPACC_FULL(n) (3 << (n * 2))
209 #define CPACC_SVC(n) (1 << (n * 2))
210 #define CPACC_DISABLE(n) (0 << (n * 2))
211
get_copro_access(void)212 static inline unsigned int get_copro_access(void)
213 {
214 unsigned int val;
215 asm("mrc p15, 0, %0, c1, c0, 2 @ get copro access"
216 : "=r" (val) : : "cc");
217 return val;
218 }
219
set_copro_access(unsigned int val)220 static inline void set_copro_access(unsigned int val)
221 {
222 asm volatile("mcr p15, 0, %0, c1, c0, 2 @ set copro access"
223 : : "r" (val) : "cc");
224 isb();
225 }
226
227 /*
228 * switch_mm() may do a full cache flush over the context switch,
229 * so enable interrupts over the context switch to avoid high
230 * latency.
231 */
232 #define __ARCH_WANT_INTERRUPTS_ON_CTXSW
233
234 /*
235 * switch_to(prev, next) should switch from task `prev' to `next'
236 * `prev' will never be the same as `next'. schedule() itself
237 * contains the memory barrier to tell GCC not to cache `current'.
238 */
239 extern struct task_struct *__switch_to(struct task_struct *, struct thread_info *, struct thread_info *);
240
241 #define switch_to(prev,next,last) \
242 do { \
243 last = __switch_to(prev,task_thread_info(prev), task_thread_info(next)); \
244 } while (0)
245
246 #if defined(CONFIG_CPU_SA1100) || defined(CONFIG_CPU_SA110)
247 /*
248 * On the StrongARM, "swp" is terminally broken since it bypasses the
249 * cache totally. This means that the cache becomes inconsistent, and,
250 * since we use normal loads/stores as well, this is really bad.
251 * Typically, this causes oopsen in filp_close, but could have other,
252 * more disastrous effects. There are two work-arounds:
253 * 1. Disable interrupts and emulate the atomic swap
254 * 2. Clean the cache, perform atomic swap, flush the cache
255 *
256 * We choose (1) since its the "easiest" to achieve here and is not
257 * dependent on the processor type.
258 *
259 * NOTE that this solution won't work on an SMP system, so explcitly
260 * forbid it here.
261 */
262 #define swp_is_buggy
263 #endif
264
__xchg(unsigned long x,volatile void * ptr,int size)265 static inline unsigned long __xchg(unsigned long x, volatile void *ptr, int size)
266 {
267 extern void __bad_xchg(volatile void *, int);
268 unsigned long ret;
269 #ifdef swp_is_buggy
270 unsigned long flags;
271 #endif
272 #if __LINUX_ARM_ARCH__ >= 6
273 unsigned int tmp;
274 #endif
275
276 smp_mb();
277
278 switch (size) {
279 #if __LINUX_ARM_ARCH__ >= 6
280 case 1:
281 asm volatile("@ __xchg1\n"
282 "1: ldrexb %0, [%3]\n"
283 " strexb %1, %2, [%3]\n"
284 " teq %1, #0\n"
285 " bne 1b"
286 : "=&r" (ret), "=&r" (tmp)
287 : "r" (x), "r" (ptr)
288 : "memory", "cc");
289 break;
290 case 4:
291 asm volatile("@ __xchg4\n"
292 "1: ldrex %0, [%3]\n"
293 " strex %1, %2, [%3]\n"
294 " teq %1, #0\n"
295 " bne 1b"
296 : "=&r" (ret), "=&r" (tmp)
297 : "r" (x), "r" (ptr)
298 : "memory", "cc");
299 break;
300 #elif defined(swp_is_buggy)
301 #ifdef CONFIG_SMP
302 #error SMP is not supported on this platform
303 #endif
304 case 1:
305 raw_local_irq_save(flags);
306 ret = *(volatile unsigned char *)ptr;
307 *(volatile unsigned char *)ptr = x;
308 raw_local_irq_restore(flags);
309 break;
310
311 case 4:
312 raw_local_irq_save(flags);
313 ret = *(volatile unsigned long *)ptr;
314 *(volatile unsigned long *)ptr = x;
315 raw_local_irq_restore(flags);
316 break;
317 #else
318 case 1:
319 asm volatile("@ __xchg1\n"
320 " swpb %0, %1, [%2]"
321 : "=&r" (ret)
322 : "r" (x), "r" (ptr)
323 : "memory", "cc");
324 break;
325 case 4:
326 asm volatile("@ __xchg4\n"
327 " swp %0, %1, [%2]"
328 : "=&r" (ret)
329 : "r" (x), "r" (ptr)
330 : "memory", "cc");
331 break;
332 #endif
333 default:
334 __bad_xchg(ptr, size), ret = 0;
335 break;
336 }
337 smp_mb();
338
339 return ret;
340 }
341
342 extern void disable_hlt(void);
343 extern void enable_hlt(void);
344
345 void cpu_idle_wait(void);
346
347 #include <asm-generic/cmpxchg-local.h>
348
349 #if __LINUX_ARM_ARCH__ < 6
350 /* min ARCH < ARMv6 */
351
352 #ifdef CONFIG_SMP
353 #error "SMP is not supported on this platform"
354 #endif
355
356 /*
357 * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make
358 * them available.
359 */
360 #define cmpxchg_local(ptr, o, n) \
361 ((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr), (unsigned long)(o),\
362 (unsigned long)(n), sizeof(*(ptr))))
363 #define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))
364
365 #ifndef CONFIG_SMP
366 #include <asm-generic/cmpxchg.h>
367 #endif
368
369 #else /* min ARCH >= ARMv6 */
370
371 extern void __bad_cmpxchg(volatile void *ptr, int size);
372
373 /*
374 * cmpxchg only support 32-bits operands on ARMv6.
375 */
376
__cmpxchg(volatile void * ptr,unsigned long old,unsigned long new,int size)377 static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
378 unsigned long new, int size)
379 {
380 unsigned long oldval, res;
381
382 switch (size) {
383 #ifndef CONFIG_CPU_V6 /* min ARCH >= ARMv6K */
384 case 1:
385 do {
386 asm volatile("@ __cmpxchg1\n"
387 " ldrexb %1, [%2]\n"
388 " mov %0, #0\n"
389 " teq %1, %3\n"
390 " strexbeq %0, %4, [%2]\n"
391 : "=&r" (res), "=&r" (oldval)
392 : "r" (ptr), "Ir" (old), "r" (new)
393 : "memory", "cc");
394 } while (res);
395 break;
396 case 2:
397 do {
398 asm volatile("@ __cmpxchg1\n"
399 " ldrexh %1, [%2]\n"
400 " mov %0, #0\n"
401 " teq %1, %3\n"
402 " strexheq %0, %4, [%2]\n"
403 : "=&r" (res), "=&r" (oldval)
404 : "r" (ptr), "Ir" (old), "r" (new)
405 : "memory", "cc");
406 } while (res);
407 break;
408 #endif
409 case 4:
410 do {
411 asm volatile("@ __cmpxchg4\n"
412 " ldrex %1, [%2]\n"
413 " mov %0, #0\n"
414 " teq %1, %3\n"
415 " strexeq %0, %4, [%2]\n"
416 : "=&r" (res), "=&r" (oldval)
417 : "r" (ptr), "Ir" (old), "r" (new)
418 : "memory", "cc");
419 } while (res);
420 break;
421 default:
422 __bad_cmpxchg(ptr, size);
423 oldval = 0;
424 }
425
426 return oldval;
427 }
428
__cmpxchg_mb(volatile void * ptr,unsigned long old,unsigned long new,int size)429 static inline unsigned long __cmpxchg_mb(volatile void *ptr, unsigned long old,
430 unsigned long new, int size)
431 {
432 unsigned long ret;
433
434 smp_mb();
435 ret = __cmpxchg(ptr, old, new, size);
436 smp_mb();
437
438 return ret;
439 }
440
441 #define cmpxchg(ptr,o,n) \
442 ((__typeof__(*(ptr)))__cmpxchg_mb((ptr), \
443 (unsigned long)(o), \
444 (unsigned long)(n), \
445 sizeof(*(ptr))))
446
__cmpxchg_local(volatile void * ptr,unsigned long old,unsigned long new,int size)447 static inline unsigned long __cmpxchg_local(volatile void *ptr,
448 unsigned long old,
449 unsigned long new, int size)
450 {
451 unsigned long ret;
452
453 switch (size) {
454 #ifdef CONFIG_CPU_V6 /* min ARCH == ARMv6 */
455 case 1:
456 case 2:
457 ret = __cmpxchg_local_generic(ptr, old, new, size);
458 break;
459 #endif
460 default:
461 ret = __cmpxchg(ptr, old, new, size);
462 }
463
464 return ret;
465 }
466
467 #define cmpxchg_local(ptr,o,n) \
468 ((__typeof__(*(ptr)))__cmpxchg_local((ptr), \
469 (unsigned long)(o), \
470 (unsigned long)(n), \
471 sizeof(*(ptr))))
472
473 #ifndef CONFIG_CPU_V6 /* min ARCH >= ARMv6K */
474
475 /*
476 * Note : ARMv7-M (currently unsupported by Linux) does not support
477 * ldrexd/strexd. If ARMv7-M is ever supported by the Linux kernel, it should
478 * not be allowed to use __cmpxchg64.
479 */
__cmpxchg64(volatile void * ptr,unsigned long long old,unsigned long long new)480 static inline unsigned long long __cmpxchg64(volatile void *ptr,
481 unsigned long long old,
482 unsigned long long new)
483 {
484 register unsigned long long oldval asm("r0");
485 register unsigned long long __old asm("r2") = old;
486 register unsigned long long __new asm("r4") = new;
487 unsigned long res;
488
489 do {
490 asm volatile(
491 " @ __cmpxchg8\n"
492 " ldrexd %1, %H1, [%2]\n"
493 " mov %0, #0\n"
494 " teq %1, %3\n"
495 " teqeq %H1, %H3\n"
496 " strexdeq %0, %4, %H4, [%2]\n"
497 : "=&r" (res), "=&r" (oldval)
498 : "r" (ptr), "Ir" (__old), "r" (__new)
499 : "memory", "cc");
500 } while (res);
501
502 return oldval;
503 }
504
__cmpxchg64_mb(volatile void * ptr,unsigned long long old,unsigned long long new)505 static inline unsigned long long __cmpxchg64_mb(volatile void *ptr,
506 unsigned long long old,
507 unsigned long long new)
508 {
509 unsigned long long ret;
510
511 smp_mb();
512 ret = __cmpxchg64(ptr, old, new);
513 smp_mb();
514
515 return ret;
516 }
517
518 #define cmpxchg64(ptr,o,n) \
519 ((__typeof__(*(ptr)))__cmpxchg64_mb((ptr), \
520 (unsigned long long)(o), \
521 (unsigned long long)(n)))
522
523 #define cmpxchg64_local(ptr,o,n) \
524 ((__typeof__(*(ptr)))__cmpxchg64((ptr), \
525 (unsigned long long)(o), \
526 (unsigned long long)(n)))
527
528 #else /* min ARCH = ARMv6 */
529
530 #define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))
531
532 #endif
533
534 #endif /* __LINUX_ARM_ARCH__ >= 6 */
535
536 #endif /* __ASSEMBLY__ */
537
538 #define arch_align_stack(x) (x)
539
540 #endif /* __KERNEL__ */
541
542 #endif
543