arch/powerpc/include/asm/system.h

   1 /*
   2  * Copyright (C) 1999 Cort Dougan <cort@cs.nmt.edu>
   3  */
   4 #ifndef _ASM_POWERPC_SYSTEM_H
   5 #define _ASM_POWERPC_SYSTEM_H
   6
   7 #include <linux/kernel.h>
   8 #include <linux/irqflags.h>
   9
  10 #include <asm/hw_irq.h>
  11
  12 /*
  13  * Memory barrier.
  14  * The sync instruction guarantees that all memory accesses initiated
  15  * by this processor have been performed (with respect to all other
  16  * mechanisms that access memory).  The eieio instruction is a barrier
  17  * providing an ordering (separately) for (a) cacheable stores and (b)
  18  * loads and stores to non-cacheable memory (e.g. I/O devices).
  19  *
  20  * mb() prevents loads and stores being reordered across this point.
  21  * rmb() prevents loads being reordered across this point.
  22  * wmb() prevents stores being reordered across this point.
  23  * read_barrier_depends() prevents data-dependent loads being reordered
  24  *      across this point (nop on PPC).
  25  *
  26  * *mb() variants without smp_ prefix must order all types of memory
  27  * operations with one another. sync is the only instruction sufficient
  28  * to do this.
  29  *
  30  * For the smp_ barriers, ordering is for cacheable memory operations
  31  * only. We have to use the sync instruction for smp_mb(), since lwsync
  32  * doesn't order loads with respect to previous stores.  Lwsync can be
  33  * used for smp_rmb() and smp_wmb().
  34  *
  35  * However, on CPUs that don't support lwsync, lwsync actually maps to a
  36  * heavy-weight sync, so smp_wmb() can be a lighter-weight eieio.
  37  */
  38 #define mb()   __asm__ __volatile__ ("sync" : : : "memory")
  39 #define rmb()  __asm__ __volatile__ ("sync" : : : "memory")
  40 #define wmb()  __asm__ __volatile__ ("sync" : : : "memory")
  41 #define read_barrier_depends()  do { } while(0)
  42
  43 #define set_mb(var, value)      do { var = value; mb(); } while (0)
  44
  45 #ifdef __KERNEL__
  46 #define AT_VECTOR_SIZE_ARCH 6 /* entries in ARCH_DLINFO */
  47 #ifdef CONFIG_SMP
  48
  49 #ifdef __SUBARCH_HAS_LWSYNC
  50 #    define SMPWMB      LWSYNC
  51 #else
  52 #    define SMPWMB      eieio
  53 #endif
  54
  55 #define smp_mb()        mb()
  56 #define smp_rmb()       __asm__ __volatile__ (stringify_in_c(LWSYNC) : : :"memory")
  57 #define smp_wmb()       __asm__ __volatile__ (stringify_in_c(SMPWMB) : : :"memory")
  58 #define smp_read_barrier_depends()      read_barrier_depends()
  59 #else
  60 #define smp_mb()        barrier()
  61 #define smp_rmb()       barrier()
  62 #define smp_wmb()       barrier()
  63 #define smp_read_barrier_depends()      do { } while(0)
  64 #endif /* CONFIG_SMP */
  65
  66 /*
  67  * This is a barrier which prevents following instructions from being
  68  * started until the value of the argument x is known.  For example, if
  69  * x is a variable loaded from memory, this prevents following
  70  * instructions from being executed until the load has been performed.
  71  */
  72 #define data_barrier(x) \
  73         asm volatile("twi 0,%0,0; isync" : : "r" (x) : "memory");
  74
  75 struct task_struct;
  76 struct pt_regs;
  77
  78 #if defined(CONFIG_DEBUGGER) || defined(CONFIG_KEXEC)
  79
  80 extern int (*__debugger)(struct pt_regs *regs);
  81 extern int (*__debugger_ipi)(struct pt_regs *regs);
  82 extern int (*__debugger_bpt)(struct pt_regs *regs);
  83 extern int (*__debugger_sstep)(struct pt_regs *regs);
  84 extern int (*__debugger_iabr_match)(struct pt_regs *regs);
  85 extern int (*__debugger_dabr_match)(struct pt_regs *regs);
  86 extern int (*__debugger_fault_handler)(struct pt_regs *regs);
  87
  88 #define DEBUGGER_BOILERPLATE(__NAME) \
  89 static inline int __NAME(struct pt_regs *regs) \
  90 { \
  91         if (unlikely(__ ## __NAME)) \
  92                 return __ ## __NAME(regs); \
  93         return 0; \
  94 }
  95
  96 DEBUGGER_BOILERPLATE(debugger)
  97 DEBUGGER_BOILERPLATE(debugger_ipi)
  98 DEBUGGER_BOILERPLATE(debugger_bpt)
  99 DEBUGGER_BOILERPLATE(debugger_sstep)
 100 DEBUGGER_BOILERPLATE(debugger_iabr_match)
 101 DEBUGGER_BOILERPLATE(debugger_dabr_match)
 102 DEBUGGER_BOILERPLATE(debugger_fault_handler)
 103
 104 #else
 105 static inline int debugger(struct pt_regs *regs) { return 0; }
 106 static inline int debugger_ipi(struct pt_regs *regs) { return 0; }
 107 static inline int debugger_bpt(struct pt_regs *regs) { return 0; }
 108 static inline int debugger_sstep(struct pt_regs *regs) { return 0; }
 109 static inline int debugger_iabr_match(struct pt_regs *regs) { return 0; }
 110 static inline int debugger_dabr_match(struct pt_regs *regs) { return 0; }
 111 static inline int debugger_fault_handler(struct pt_regs *regs) { return 0; }
 112 #endif
 113
 114 extern int set_dabr(unsigned long dabr);
 115 #ifdef CONFIG_PPC_ADV_DEBUG_REGS
 116 extern void do_send_trap(struct pt_regs *regs, unsigned long address,
 117                          unsigned long error_code, int signal_code, int brkpt);
 118 #else
 119 extern void do_dabr(struct pt_regs *regs, unsigned long address,
 120                     unsigned long error_code);
 121 #endif
 122 extern void print_backtrace(unsigned long *);
 123 extern void show_regs(struct pt_regs * regs);
 124 extern void flush_instruction_cache(void);
 125 extern void hard_reset_now(void);
 126 extern void poweroff_now(void);
 127
 128 #ifdef CONFIG_6xx
 129 extern long _get_L2CR(void);
 130 extern long _get_L3CR(void);
 131 extern void _set_L2CR(unsigned long);
 132 extern void _set_L3CR(unsigned long);
 133 #else
 134 #define _get_L2CR()     0L
 135 #define _get_L3CR()     0L
 136 #define _set_L2CR(val)  do { } while(0)
 137 #define _set_L3CR(val)  do { } while(0)
 138 #endif
 139
 140 extern void via_cuda_init(void);
 141 extern void read_rtc_time(void);
 142 extern void pmac_find_display(void);
 143 extern void giveup_fpu(struct task_struct *);
 144 extern void disable_kernel_fp(void);
 145 extern void enable_kernel_fp(void);
 146 extern void flush_fp_to_thread(struct task_struct *);
 147 extern void enable_kernel_altivec(void);
 148 extern void giveup_altivec(struct task_struct *);
 149 extern void load_up_altivec(struct task_struct *);
 150 extern int emulate_altivec(struct pt_regs *);
 151 extern void __giveup_vsx(struct task_struct *);
 152 extern void giveup_vsx(struct task_struct *);
 153 extern void enable_kernel_spe(void);
 154 extern void giveup_spe(struct task_struct *);
 155 extern void load_up_spe(struct task_struct *);
 156 extern int fix_alignment(struct pt_regs *);
 157 extern void cvt_fd(float *from, double *to);
 158 extern void cvt_df(double *from, float *to);
 159
 160 #ifndef CONFIG_SMP
 161 extern void discard_lazy_cpu_state(void);
 162 #else
 163 static inline void discard_lazy_cpu_state(void)
 164 {
 165 }
 166 #endif
 167
 168 #ifdef CONFIG_ALTIVEC
 169 extern void flush_altivec_to_thread(struct task_struct *);
 170 #else
 171 static inline void flush_altivec_to_thread(struct task_struct *t)
 172 {
 173 }
 174 #endif
 175
 176 #ifdef CONFIG_VSX
 177 extern void flush_vsx_to_thread(struct task_struct *);
 178 #else
 179 static inline void flush_vsx_to_thread(struct task_struct *t)
 180 {
 181 }
 182 #endif
 183
 184 #ifdef CONFIG_SPE
 185 extern void flush_spe_to_thread(struct task_struct *);
 186 #else
 187 static inline void flush_spe_to_thread(struct task_struct *t)
 188 {
 189 }
 190 #endif
 191
 192 extern int call_rtas(const char *, int, int, unsigned long *, ...);
 193 extern void cacheable_memzero(void *p, unsigned int nb);
 194 extern void *cacheable_memcpy(void *, const void *, unsigned int);
 195 extern int do_page_fault(struct pt_regs *, unsigned long, unsigned long);
 196 extern void bad_page_fault(struct pt_regs *, unsigned long, int);
 197 extern int die(const char *, struct pt_regs *, long);
 198 extern void _exception(int, struct pt_regs *, int, unsigned long);
 199 extern void _nmask_and_or_msr(unsigned long nmask, unsigned long or_val);
 200
 201 #ifdef CONFIG_BOOKE_WDT
 202 extern u32 booke_wdt_enabled;
 203 extern u32 booke_wdt_period;
 204 #endif /* CONFIG_BOOKE_WDT */
 205
 206 struct device_node;
 207 extern void note_scsi_host(struct device_node *, void *);
 208
 209 extern struct task_struct *__switch_to(struct task_struct *,
 210         struct task_struct *);
 211 #define switch_to(prev, next, last)     ((last) = __switch_to((prev), (next)))
 212
 213 struct thread_struct;
 214 extern struct task_struct *_switch(struct thread_struct *prev,
 215                                    struct thread_struct *next);
 216
 217 extern unsigned int rtas_data;
 218 extern int mem_init_done;       /* set on boot once kmalloc can be called */
 219 extern int init_bootmem_done;   /* set once bootmem is available */
 220 extern phys_addr_t memory_limit;
 221 extern unsigned long klimit;
 222
 223 extern void *alloc_maybe_bootmem(size_t size, gfp_t mask);
 224 extern void *zalloc_maybe_bootmem(size_t size, gfp_t mask);
 225
 226 extern int powersave_nap;       /* set if nap mode can be used in idle loop */
 227
 228 /*
 229  * Atomic exchange
 230  *
 231  * Changes the memory location '*ptr' to be val and returns
 232  * the previous value stored there.
 233  */
 234 static __always_inline unsigned long
 235 __xchg_u32(volatile void *p, unsigned long val)
 236 {
 237         unsigned long prev;
 238
 239         __asm__ __volatile__(
 240         PPC_RELEASE_BARRIER
 241 "1:     lwarx   %0,0,%2 \n"
 242         PPC405_ERR77(0,%2)
 243 "       stwcx.  %3,0,%2 \n\
 244         bne-    1b"
 245         PPC_ACQUIRE_BARRIER
 246         : "=&r" (prev), "+m" (*(volatile unsigned int *)p)
 247         : "r" (p), "r" (val)
 248         : "cc", "memory");
 249
 250         return prev;
 251 }
 252
 253 /*
 254  * Atomic exchange
 255  *
 256  * Changes the memory location '*ptr' to be val and returns
 257  * the previous value stored there.
 258  */
 259 static __always_inline unsigned long
 260 __xchg_u32_local(volatile void *p, unsigned long val)
 261 {
 262         unsigned long prev;
 263
 264         __asm__ __volatile__(
 265 "1:     lwarx   %0,0,%2 \n"
 266         PPC405_ERR77(0,%2)
 267 "       stwcx.  %3,0,%2 \n\
 268         bne-    1b"
 269         : "=&r" (prev), "+m" (*(volatile unsigned int *)p)
 270         : "r" (p), "r" (val)
 271         : "cc", "memory");
 272
 273         return prev;
 274 }
 275
 276 #ifdef CONFIG_PPC64
 277 static __always_inline unsigned long
 278 __xchg_u64(volatile void *p, unsigned long val)
 279 {
 280         unsigned long prev;
 281
 282         __asm__ __volatile__(
 283         PPC_RELEASE_BARRIER
 284 "1:     ldarx   %0,0,%2 \n"
 285         PPC405_ERR77(0,%2)
 286 "       stdcx.  %3,0,%2 \n\
 287         bne-    1b"
 288         PPC_ACQUIRE_BARRIER
 289         : "=&r" (prev), "+m" (*(volatile unsigned long *)p)
 290         : "r" (p), "r" (val)
 291         : "cc", "memory");
 292
 293         return prev;
 294 }
 295
 296 static __always_inline unsigned long
 297 __xchg_u64_local(volatile void *p, unsigned long val)
 298 {
 299         unsigned long prev;
 300
 301         __asm__ __volatile__(
 302 "1:     ldarx   %0,0,%2 \n"
 303         PPC405_ERR77(0,%2)
 304 "       stdcx.  %3,0,%2 \n\
 305         bne-    1b"
 306         : "=&r" (prev), "+m" (*(volatile unsigned long *)p)
 307         : "r" (p), "r" (val)
 308         : "cc", "memory");
 309
 310         return prev;
 311 }
 312 #endif
 313
 314 /*
 315  * This function doesn't exist, so you'll get a linker error
 316  * if something tries to do an invalid xchg().
 317  */
 318 extern void __xchg_called_with_bad_pointer(void);
 319
 320 static __always_inline unsigned long
 321 __xchg(volatile void *ptr, unsigned long x, unsigned int size)
 322 {
 323         switch (size) {
 324         case 4:
 325                 return __xchg_u32(ptr, x);
 326 #ifdef CONFIG_PPC64
 327         case 8:
 328                 return __xchg_u64(ptr, x);
 329 #endif
 330         }
 331         __xchg_called_with_bad_pointer();
 332         return x;
 333 }
 334
 335 static __always_inline unsigned long
 336 __xchg_local(volatile void *ptr, unsigned long x, unsigned int size)
 337 {
 338         switch (size) {
 339         case 4:
 340                 return __xchg_u32_local(ptr, x);
 341 #ifdef CONFIG_PPC64
 342         case 8:
 343                 return __xchg_u64_local(ptr, x);
 344 #endif
 345         }
 346         __xchg_called_with_bad_pointer();
 347         return x;
 348 }
 349 #define xchg(ptr,x)                                                          \
 350   ({                                                                         \
 351      __typeof__(*(ptr)) _x_ = (x);                                           \
 352      (__typeof__(*(ptr))) __xchg((ptr), (unsigned long)_x_, sizeof(*(ptr))); \
 353   })
 354
 355 #define xchg_local(ptr,x)                                                    \
 356   ({                                                                         \
 357      __typeof__(*(ptr)) _x_ = (x);                                           \
 358      (__typeof__(*(ptr))) __xchg_local((ptr),                                \
 359                 (unsigned long)_x_, sizeof(*(ptr)));                         \
 360   })
 361
 362 /*
 363  * Compare and exchange - if *p == old, set it to new,
 364  * and return the old value of *p.
 365  */
 366 #define __HAVE_ARCH_CMPXCHG     1
 367
 368 static __always_inline unsigned long
 369 __cmpxchg_u32(volatile unsigned int *p, unsigned long old, unsigned long new)
 370 {
 371         unsigned int prev;
 372
 373         __asm__ __volatile__ (
 374         PPC_RELEASE_BARRIER
 375 "1:     lwarx   %0,0,%2         # __cmpxchg_u32\n\
 376         cmpw    0,%0,%3\n\
 377         bne-    2f\n"
 378         PPC405_ERR77(0,%2)
 379 "       stwcx.  %4,0,%2\n\
 380         bne-    1b"
 381         PPC_ACQUIRE_BARRIER
 382         "\n\
 383 2:"
 384         : "=&r" (prev), "+m" (*p)
 385         : "r" (p), "r" (old), "r" (new)
 386         : "cc", "memory");
 387
 388         return prev;
 389 }
 390
 391 static __always_inline unsigned long
 392 __cmpxchg_u32_local(volatile unsigned int *p, unsigned long old,
 393                         unsigned long new)
 394 {
 395         unsigned int prev;
 396
 397         __asm__ __volatile__ (
 398 "1:     lwarx   %0,0,%2         # __cmpxchg_u32\n\
 399         cmpw    0,%0,%3\n\
 400         bne-    2f\n"
 401         PPC405_ERR77(0,%2)
 402 "       stwcx.  %4,0,%2\n\
 403         bne-    1b"
 404         "\n\
 405 2:"
 406         : "=&r" (prev), "+m" (*p)
 407         : "r" (p), "r" (old), "r" (new)
 408         : "cc", "memory");
 409
 410         return prev;
 411 }
 412
 413 #ifdef CONFIG_PPC64
 414 static __always_inline unsigned long
 415 __cmpxchg_u64(volatile unsigned long *p, unsigned long old, unsigned long new)
 416 {
 417         unsigned long prev;
 418
 419         __asm__ __volatile__ (
 420         PPC_RELEASE_BARRIER
 421 "1:     ldarx   %0,0,%2         # __cmpxchg_u64\n\
 422         cmpd    0,%0,%3\n\
 423         bne-    2f\n\
 424         stdcx.  %4,0,%2\n\
 425         bne-    1b"
 426         PPC_ACQUIRE_BARRIER
 427         "\n\
 428 2:"
 429         : "=&r" (prev), "+m" (*p)
 430         : "r" (p), "r" (old), "r" (new)
 431         : "cc", "memory");
 432
 433         return prev;
 434 }
 435
 436 static __always_inline unsigned long
 437 __cmpxchg_u64_local(volatile unsigned long *p, unsigned long old,
 438                         unsigned long new)
 439 {
 440         unsigned long prev;
 441
 442         __asm__ __volatile__ (
 443 "1:     ldarx   %0,0,%2         # __cmpxchg_u64\n\
 444         cmpd    0,%0,%3\n\
 445         bne-    2f\n\
 446         stdcx.  %4,0,%2\n\
 447         bne-    1b"
 448         "\n\
 449 2:"
 450         : "=&r" (prev), "+m" (*p)
 451         : "r" (p), "r" (old), "r" (new)
 452         : "cc", "memory");
 453
 454         return prev;
 455 }
 456 #endif
 457
 458 /* This function doesn't exist, so you'll get a linker error
 459    if something tries to do an invalid cmpxchg().  */
 460 extern void __cmpxchg_called_with_bad_pointer(void);
 461
 462 static __always_inline unsigned long
 463 __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new,
 464           unsigned int size)
 465 {
 466         switch (size) {
 467         case 4:
 468                 return __cmpxchg_u32(ptr, old, new);
 469 #ifdef CONFIG_PPC64
 470         case 8:
 471                 return __cmpxchg_u64(ptr, old, new);
 472 #endif
 473         }
 474         __cmpxchg_called_with_bad_pointer();
 475         return old;
 476 }
 477
 478 static __always_inline unsigned long
 479 __cmpxchg_local(volatile void *ptr, unsigned long old, unsigned long new,
 480           unsigned int size)
 481 {
 482         switch (size) {
 483         case 4:
 484                 return __cmpxchg_u32_local(ptr, old, new);
 485 #ifdef CONFIG_PPC64
 486         case 8:
 487                 return __cmpxchg_u64_local(ptr, old, new);
 488 #endif
 489         }
 490         __cmpxchg_called_with_bad_pointer();
 491         return old;
 492 }
 493
 494 #define cmpxchg(ptr, o, n)                                               \
 495   ({                                                                     \
 496      __typeof__(*(ptr)) _o_ = (o);                                       \
 497      __typeof__(*(ptr)) _n_ = (n);                                       \
 498      (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_,           \
 499                                     (unsigned long)_n_, sizeof(*(ptr))); \
 500   })
 501
 502
 503 #define cmpxchg_local(ptr, o, n)                                         \
 504   ({                                                                     \
 505      __typeof__(*(ptr)) _o_ = (o);                                       \
 506      __typeof__(*(ptr)) _n_ = (n);                                       \
 507      (__typeof__(*(ptr))) __cmpxchg_local((ptr), (unsigned long)_o_,     \
 508                                     (unsigned long)_n_, sizeof(*(ptr))); \
 509   })
 510
 511 #ifdef CONFIG_PPC64
 512 /*
 513  * We handle most unaligned accesses in hardware. On the other hand
 514  * unaligned DMA can be very expensive on some ppc64 IO chips (it does
 515  * powers of 2 writes until it reaches sufficient alignment).
 516  *
 517  * Based on this we disable the IP header alignment in network drivers.
 518  */
 519 #define NET_IP_ALIGN    0
 520
 521 #define cmpxchg64(ptr, o, n)                                            \
 522   ({                                                                    \
 523         BUILD_BUG_ON(sizeof(*(ptr)) != 8);                              \
 524         cmpxchg((ptr), (o), (n));                                       \
 525   })
 526 #define cmpxchg64_local(ptr, o, n)                                      \
 527   ({                                                                    \
 528         BUILD_BUG_ON(sizeof(*(ptr)) != 8);                              \
 529         cmpxchg_local((ptr), (o), (n));                                 \
 530   })
 531 #else
 532 #include <asm-generic/cmpxchg-local.h>
 533 #define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))
 534 #endif
 535
 536 extern unsigned long arch_align_stack(unsigned long sp);
 537
 538 /* Used in very early kernel initialization. */
 539 extern unsigned long reloc_offset(void);
 540 extern unsigned long add_reloc_offset(unsigned long);
 541 extern void reloc_got2(unsigned long);
 542
 543 #define PTRRELOC(x)     ((typeof(x)) add_reloc_offset((unsigned long)(x)))
 544
 545 extern struct dentry *powerpc_debugfs_root;
 546
 547 #endif /* __KERNEL__ */
 548 #endif /* _ASM_POWERPC_SYSTEM_H */