include/asm-powerpc/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
   9 #include <asm/hw_irq.h>
  10
  11 /*
  12  * Memory barrier.
  13  * The sync instruction guarantees that all memory accesses initiated
  14  * by this processor have been performed (with respect to all other
  15  * mechanisms that access memory).  The eieio instruction is a barrier
  16  * providing an ordering (separately) for (a) cacheable stores and (b)
  17  * loads and stores to non-cacheable memory (e.g. I/O devices).
  18  *
  19  * mb() prevents loads and stores being reordered across this point.
  20  * rmb() prevents loads being reordered across this point.
  21  * wmb() prevents stores being reordered across this point.
  22  * read_barrier_depends() prevents data-dependent loads being reordered
  23  *      across this point (nop on PPC).
  24  *
  25  * We have to use the sync instructions for mb(), since lwsync doesn't
  26  * order loads with respect to previous stores.  Lwsync is fine for
  27  * rmb(), though. Note that rmb() actually uses a sync on 32-bit
  28  * architectures.
  29  *
  30  * For wmb(), we use sync since wmb is used in drivers to order
  31  * stores to system memory with respect to writes to the device.
  32  * However, smp_wmb() can be a lighter-weight eieio barrier on
  33  * SMP since it is only used to order updates to system memory.
  34  */
  35 #define mb()   __asm__ __volatile__ ("sync" : : : "memory")
  36 #define rmb()  __asm__ __volatile__ (__stringify(LWSYNC) : : : "memory")
  37 #define wmb()  __asm__ __volatile__ ("sync" : : : "memory")
  38 #define read_barrier_depends()  do { } while(0)
  39
  40 #define set_mb(var, value)      do { var = value; mb(); } while (0)
  41
  42 #ifdef __KERNEL__
  43 #define AT_VECTOR_SIZE_ARCH 6 /* entries in ARCH_DLINFO */
  44 #ifdef CONFIG_SMP
  45 #define smp_mb()        mb()
  46 #define smp_rmb()       rmb()
  47 #define smp_wmb()       eieio()
  48 #define smp_read_barrier_depends()      read_barrier_depends()
  49 #else
  50 #define smp_mb()        barrier()
  51 #define smp_rmb()       barrier()
  52 #define smp_wmb()       barrier()
  53 #define smp_read_barrier_depends()      do { } while(0)
  54 #endif /* CONFIG_SMP */
  55
  56 /*
  57  * This is a barrier which prevents following instructions from being
  58  * started until the value of the argument x is known.  For example, if
  59  * x is a variable loaded from memory, this prevents following
  60  * instructions from being executed until the load has been performed.
  61  */
  62 #define data_barrier(x) \
  63         asm volatile("twi 0,%0,0; isync" : : "r" (x) : "memory");
  64
  65 struct task_struct;
  66 struct pt_regs;
  67
  68 #if defined(CONFIG_DEBUGGER) || defined(CONFIG_KEXEC)
  69
  70 extern int (*__debugger)(struct pt_regs *regs);
  71 extern int (*__debugger_ipi)(struct pt_regs *regs);
  72 extern int (*__debugger_bpt)(struct pt_regs *regs);
  73 extern int (*__debugger_sstep)(struct pt_regs *regs);
  74 extern int (*__debugger_iabr_match)(struct pt_regs *regs);
  75 extern int (*__debugger_dabr_match)(struct pt_regs *regs);
  76 extern int (*__debugger_fault_handler)(struct pt_regs *regs);
  77
  78 #define DEBUGGER_BOILERPLATE(__NAME) \
  79 static inline int __NAME(struct pt_regs *regs) \
  80 { \
  81         if (unlikely(__ ## __NAME)) \
  82                 return __ ## __NAME(regs); \
  83         return 0; \
  84 }
  85
  86 DEBUGGER_BOILERPLATE(debugger)
  87 DEBUGGER_BOILERPLATE(debugger_ipi)
  88 DEBUGGER_BOILERPLATE(debugger_bpt)
  89 DEBUGGER_BOILERPLATE(debugger_sstep)
  90 DEBUGGER_BOILERPLATE(debugger_iabr_match)
  91 DEBUGGER_BOILERPLATE(debugger_dabr_match)
  92 DEBUGGER_BOILERPLATE(debugger_fault_handler)
  93
  94 #else
  95 static inline int debugger(struct pt_regs *regs) { return 0; }
  96 static inline int debugger_ipi(struct pt_regs *regs) { return 0; }
  97 static inline int debugger_bpt(struct pt_regs *regs) { return 0; }
  98 static inline int debugger_sstep(struct pt_regs *regs) { return 0; }
  99 static inline int debugger_iabr_match(struct pt_regs *regs) { return 0; }
 100 static inline int debugger_dabr_match(struct pt_regs *regs) { return 0; }
 101 static inline int debugger_fault_handler(struct pt_regs *regs) { return 0; }
 102 #endif
 103
 104 extern int set_dabr(unsigned long dabr);
 105 extern void print_backtrace(unsigned long *);
 106 extern void show_regs(struct pt_regs * regs);
 107 extern void flush_instruction_cache(void);
 108 extern void hard_reset_now(void);
 109 extern void poweroff_now(void);
 110
 111 #ifdef CONFIG_6xx
 112 extern long _get_L2CR(void);
 113 extern long _get_L3CR(void);
 114 extern void _set_L2CR(unsigned long);
 115 extern void _set_L3CR(unsigned long);
 116 #else
 117 #define _get_L2CR()     0L
 118 #define _get_L3CR()     0L
 119 #define _set_L2CR(val)  do { } while(0)
 120 #define _set_L3CR(val)  do { } while(0)
 121 #endif
 122
 123 extern void via_cuda_init(void);
 124 extern void read_rtc_time(void);
 125 extern void pmac_find_display(void);
 126 extern void giveup_fpu(struct task_struct *);
 127 extern void disable_kernel_fp(void);
 128 extern void enable_kernel_fp(void);
 129 extern void flush_fp_to_thread(struct task_struct *);
 130 extern void enable_kernel_altivec(void);
 131 extern void giveup_altivec(struct task_struct *);
 132 extern void load_up_altivec(struct task_struct *);
 133 extern int emulate_altivec(struct pt_regs *);
 134 extern void enable_kernel_spe(void);
 135 extern void giveup_spe(struct task_struct *);
 136 extern void load_up_spe(struct task_struct *);
 137 extern int fix_alignment(struct pt_regs *);
 138 extern void cvt_fd(float *from, double *to, struct thread_struct *thread);
 139 extern void cvt_df(double *from, float *to, struct thread_struct *thread);
 140
 141 #ifndef CONFIG_SMP
 142 extern void discard_lazy_cpu_state(void);
 143 #else
 144 static inline void discard_lazy_cpu_state(void)
 145 {
 146 }
 147 #endif
 148
 149 #ifdef CONFIG_ALTIVEC
 150 extern void flush_altivec_to_thread(struct task_struct *);
 151 #else
 152 static inline void flush_altivec_to_thread(struct task_struct *t)
 153 {
 154 }
 155 #endif
 156
 157 #ifdef CONFIG_SPE
 158 extern void flush_spe_to_thread(struct task_struct *);
 159 #else
 160 static inline void flush_spe_to_thread(struct task_struct *t)
 161 {
 162 }
 163 #endif
 164
 165 extern int call_rtas(const char *, int, int, unsigned long *, ...);
 166 extern void cacheable_memzero(void *p, unsigned int nb);
 167 extern void *cacheable_memcpy(void *, const void *, unsigned int);
 168 extern int do_page_fault(struct pt_regs *, unsigned long, unsigned long);
 169 extern void bad_page_fault(struct pt_regs *, unsigned long, int);
 170 extern int die(const char *, struct pt_regs *, long);
 171 extern void _exception(int, struct pt_regs *, int, unsigned long);
 172 extern void _nmask_and_or_msr(unsigned long nmask, unsigned long or_val);
 173
 174 #ifdef CONFIG_BOOKE_WDT
 175 extern u32 booke_wdt_enabled;
 176 extern u32 booke_wdt_period;
 177 #endif /* CONFIG_BOOKE_WDT */
 178
 179 struct device_node;
 180 extern void note_scsi_host(struct device_node *, void *);
 181
 182 extern struct task_struct *__switch_to(struct task_struct *,
 183         struct task_struct *);
 184 #define switch_to(prev, next, last)     ((last) = __switch_to((prev), (next)))
 185
 186 struct thread_struct;
 187 extern struct task_struct *_switch(struct thread_struct *prev,
 188                                    struct thread_struct *next);
 189
 190 extern unsigned int rtas_data;
 191 extern int mem_init_done;       /* set on boot once kmalloc can be called */
 192 extern unsigned long memory_limit;
 193 extern unsigned long klimit;
 194
 195 extern void *alloc_maybe_bootmem(size_t size, gfp_t mask);
 196 extern void *zalloc_maybe_bootmem(size_t size, gfp_t mask);
 197
 198 extern int powersave_nap;       /* set if nap mode can be used in idle loop */
 199
 200 /*
 201  * Atomic exchange
 202  *
 203  * Changes the memory location '*ptr' to be val and returns
 204  * the previous value stored there.
 205  */
 206 static __inline__ unsigned long
 207 __xchg_u32(volatile void *p, unsigned long val)
 208 {
 209         unsigned long prev;
 210
 211         __asm__ __volatile__(
 212         LWSYNC_ON_SMP
 213 "1:     lwarx   %0,0,%2 \n"
 214         PPC405_ERR77(0,%2)
 215 "       stwcx.  %3,0,%2 \n\
 216         bne-    1b"
 217         ISYNC_ON_SMP
 218         : "=&r" (prev), "+m" (*(volatile unsigned int *)p)
 219         : "r" (p), "r" (val)
 220         : "cc", "memory");
 221
 222         return prev;
 223 }
 224
 225 /*
 226  * Atomic exchange
 227  *
 228  * Changes the memory location '*ptr' to be val and returns
 229  * the previous value stored there.
 230  */
 231 static __inline__ unsigned long
 232 __xchg_u32_local(volatile void *p, unsigned long val)
 233 {
 234         unsigned long prev;
 235
 236         __asm__ __volatile__(
 237 "1:     lwarx   %0,0,%2 \n"
 238         PPC405_ERR77(0,%2)
 239 "       stwcx.  %3,0,%2 \n\
 240         bne-    1b"
 241         : "=&r" (prev), "+m" (*(volatile unsigned int *)p)
 242         : "r" (p), "r" (val)
 243         : "cc", "memory");
 244
 245         return prev;
 246 }
 247
 248 #ifdef CONFIG_PPC64
 249 static __inline__ unsigned long
 250 __xchg_u64(volatile void *p, unsigned long val)
 251 {
 252         unsigned long prev;
 253
 254         __asm__ __volatile__(
 255         LWSYNC_ON_SMP
 256 "1:     ldarx   %0,0,%2 \n"
 257         PPC405_ERR77(0,%2)
 258 "       stdcx.  %3,0,%2 \n\
 259         bne-    1b"
 260         ISYNC_ON_SMP
 261         : "=&r" (prev), "+m" (*(volatile unsigned long *)p)
 262         : "r" (p), "r" (val)
 263         : "cc", "memory");
 264
 265         return prev;
 266 }
 267
 268 static __inline__ unsigned long
 269 __xchg_u64_local(volatile void *p, unsigned long val)
 270 {
 271         unsigned long prev;
 272
 273         __asm__ __volatile__(
 274 "1:     ldarx   %0,0,%2 \n"
 275         PPC405_ERR77(0,%2)
 276 "       stdcx.  %3,0,%2 \n\
 277         bne-    1b"
 278         : "=&r" (prev), "+m" (*(volatile unsigned long *)p)
 279         : "r" (p), "r" (val)
 280         : "cc", "memory");
 281
 282         return prev;
 283 }
 284 #endif
 285
 286 /*
 287  * This function doesn't exist, so you'll get a linker error
 288  * if something tries to do an invalid xchg().
 289  */
 290 extern void __xchg_called_with_bad_pointer(void);
 291
 292 static __inline__ unsigned long
 293 __xchg(volatile void *ptr, unsigned long x, unsigned int size)
 294 {
 295         switch (size) {
 296         case 4:
 297                 return __xchg_u32(ptr, x);
 298 #ifdef CONFIG_PPC64
 299         case 8:
 300                 return __xchg_u64(ptr, x);
 301 #endif
 302         }
 303         __xchg_called_with_bad_pointer();
 304         return x;
 305 }
 306
 307 static __inline__ unsigned long
 308 __xchg_local(volatile void *ptr, unsigned long x, unsigned int size)
 309 {
 310         switch (size) {
 311         case 4:
 312                 return __xchg_u32_local(ptr, x);
 313 #ifdef CONFIG_PPC64
 314         case 8:
 315                 return __xchg_u64_local(ptr, x);
 316 #endif
 317         }
 318         __xchg_called_with_bad_pointer();
 319         return x;
 320 }
 321 #define xchg(ptr,x)                                                          \
 322   ({                                                                         \
 323      __typeof__(*(ptr)) _x_ = (x);                                           \
 324      (__typeof__(*(ptr))) __xchg((ptr), (unsigned long)_x_, sizeof(*(ptr))); \
 325   })
 326
 327 #define xchg_local(ptr,x)                                                    \
 328   ({                                                                         \
 329      __typeof__(*(ptr)) _x_ = (x);                                           \
 330      (__typeof__(*(ptr))) __xchg_local((ptr),                                \
 331                 (unsigned long)_x_, sizeof(*(ptr)));                         \
 332   })
 333
 334 /*
 335  * Compare and exchange - if *p == old, set it to new,
 336  * and return the old value of *p.
 337  */
 338 #define __HAVE_ARCH_CMPXCHG     1
 339
 340 static __inline__ unsigned long
 341 __cmpxchg_u32(volatile unsigned int *p, unsigned long old, unsigned long new)
 342 {
 343         unsigned int prev;
 344
 345         __asm__ __volatile__ (
 346         LWSYNC_ON_SMP
 347 "1:     lwarx   %0,0,%2         # __cmpxchg_u32\n\
 348         cmpw    0,%0,%3\n\
 349         bne-    2f\n"
 350         PPC405_ERR77(0,%2)
 351 "       stwcx.  %4,0,%2\n\
 352         bne-    1b"
 353         ISYNC_ON_SMP
 354         "\n\
 355 2:"
 356         : "=&r" (prev), "+m" (*p)
 357         : "r" (p), "r" (old), "r" (new)
 358         : "cc", "memory");
 359
 360         return prev;
 361 }
 362
 363 static __inline__ unsigned long
 364 __cmpxchg_u32_local(volatile unsigned int *p, unsigned long old,
 365                         unsigned long new)
 366 {
 367         unsigned int prev;
 368
 369         __asm__ __volatile__ (
 370 "1:     lwarx   %0,0,%2         # __cmpxchg_u32\n\
 371         cmpw    0,%0,%3\n\
 372         bne-    2f\n"
 373         PPC405_ERR77(0,%2)
 374 "       stwcx.  %4,0,%2\n\
 375         bne-    1b"
 376         "\n\
 377 2:"
 378         : "=&r" (prev), "+m" (*p)
 379         : "r" (p), "r" (old), "r" (new)
 380         : "cc", "memory");
 381
 382         return prev;
 383 }
 384
 385 #ifdef CONFIG_PPC64
 386 static __inline__ unsigned long
 387 __cmpxchg_u64(volatile unsigned long *p, unsigned long old, unsigned long new)
 388 {
 389         unsigned long prev;
 390
 391         __asm__ __volatile__ (
 392         LWSYNC_ON_SMP
 393 "1:     ldarx   %0,0,%2         # __cmpxchg_u64\n\
 394         cmpd    0,%0,%3\n\
 395         bne-    2f\n\
 396         stdcx.  %4,0,%2\n\
 397         bne-    1b"
 398         ISYNC_ON_SMP
 399         "\n\
 400 2:"
 401         : "=&r" (prev), "+m" (*p)
 402         : "r" (p), "r" (old), "r" (new)
 403         : "cc", "memory");
 404
 405         return prev;
 406 }
 407
 408 static __inline__ unsigned long
 409 __cmpxchg_u64_local(volatile unsigned long *p, unsigned long old,
 410                         unsigned long new)
 411 {
 412         unsigned long prev;
 413
 414         __asm__ __volatile__ (
 415 "1:     ldarx   %0,0,%2         # __cmpxchg_u64\n\
 416         cmpd    0,%0,%3\n\
 417         bne-    2f\n\
 418         stdcx.  %4,0,%2\n\
 419         bne-    1b"
 420         "\n\
 421 2:"
 422         : "=&r" (prev), "+m" (*p)
 423         : "r" (p), "r" (old), "r" (new)
 424         : "cc", "memory");
 425
 426         return prev;
 427 }
 428 #endif
 429
 430 /* This function doesn't exist, so you'll get a linker error
 431    if something tries to do an invalid cmpxchg().  */
 432 extern void __cmpxchg_called_with_bad_pointer(void);
 433
 434 static __inline__ unsigned long
 435 __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new,
 436           unsigned int size)
 437 {
 438         switch (size) {
 439         case 4:
 440                 return __cmpxchg_u32(ptr, old, new);
 441 #ifdef CONFIG_PPC64
 442         case 8:
 443                 return __cmpxchg_u64(ptr, old, new);
 444 #endif
 445         }
 446         __cmpxchg_called_with_bad_pointer();
 447         return old;
 448 }
 449
 450 static __inline__ unsigned long
 451 __cmpxchg_local(volatile void *ptr, unsigned long old, unsigned long new,
 452           unsigned int size)
 453 {
 454         switch (size) {
 455         case 4:
 456                 return __cmpxchg_u32_local(ptr, old, new);
 457 #ifdef CONFIG_PPC64
 458         case 8:
 459                 return __cmpxchg_u64_local(ptr, old, new);
 460 #endif
 461         }
 462         __cmpxchg_called_with_bad_pointer();
 463         return old;
 464 }
 465
 466 #define cmpxchg(ptr, o, n)                                               \
 467   ({                                                                     \
 468      __typeof__(*(ptr)) _o_ = (o);                                       \
 469      __typeof__(*(ptr)) _n_ = (n);                                       \
 470      (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_,           \
 471                                     (unsigned long)_n_, sizeof(*(ptr))); \
 472   })
 473
 474
 475 #define cmpxchg_local(ptr, o, n)                                         \
 476   ({                                                                     \
 477      __typeof__(*(ptr)) _o_ = (o);                                       \
 478      __typeof__(*(ptr)) _n_ = (n);                                       \
 479      (__typeof__(*(ptr))) __cmpxchg_local((ptr), (unsigned long)_o_,     \
 480                                     (unsigned long)_n_, sizeof(*(ptr))); \
 481   })
 482
 483 #ifdef CONFIG_PPC64
 484 /*
 485  * We handle most unaligned accesses in hardware. On the other hand
 486  * unaligned DMA can be very expensive on some ppc64 IO chips (it does
 487  * powers of 2 writes until it reaches sufficient alignment).
 488  *
 489  * Based on this we disable the IP header alignment in network drivers.
 490  * We also modify NET_SKB_PAD to be a cacheline in size, thus maintaining
 491  * cacheline alignment of buffers.
 492  */
 493 #define NET_IP_ALIGN    0
 494 #define NET_SKB_PAD     L1_CACHE_BYTES
 495
 496 #define cmpxchg64(ptr, o, n)                                            \
 497   ({                                                                    \
 498         BUILD_BUG_ON(sizeof(*(ptr)) != 8);                              \
 499         cmpxchg((ptr), (o), (n));                                       \
 500   })
 501 #define cmpxchg64_local(ptr, o, n)                                      \
 502   ({                                                                    \
 503         BUILD_BUG_ON(sizeof(*(ptr)) != 8);                              \
 504         cmpxchg_local((ptr), (o), (n));                                 \
 505   })
 506 #else
 507 #include <asm-generic/cmpxchg-local.h>
 508 #define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))
 509 #endif
 510
 511 #define arch_align_stack(x) (x)
 512
 513 /* Used in very early kernel initialization. */
 514 extern unsigned long reloc_offset(void);
 515 extern unsigned long add_reloc_offset(unsigned long);
 516 extern void reloc_got2(unsigned long);
 517
 518 #define PTRRELOC(x)     ((typeof(x)) add_reloc_offset((unsigned long)(x)))
 519
 520 static inline void create_instruction(unsigned long addr, unsigned int instr)
 521 {
 522         unsigned int *p;
 523         p  = (unsigned int *)addr;
 524         *p = instr;
 525         asm ("dcbst 0, %0; sync; icbi 0,%0; sync; isync" : : "r" (p));
 526 }
 527
 528 /* Flags for create_branch:
 529  * "b"   == create_branch(addr, target, 0);
 530  * "ba"  == create_branch(addr, target, BRANCH_ABSOLUTE);
 531  * "bl"  == create_branch(addr, target, BRANCH_SET_LINK);
 532  * "bla" == create_branch(addr, target, BRANCH_ABSOLUTE | BRANCH_SET_LINK);
 533  */
 534 #define BRANCH_SET_LINK 0x1
 535 #define BRANCH_ABSOLUTE 0x2
 536
 537 static inline void create_branch(unsigned long addr,
 538                 unsigned long target, int flags)
 539 {
 540         unsigned int instruction;
 541
 542         if (! (flags & BRANCH_ABSOLUTE))
 543                 target = target - addr;
 544
 545         /* Mask out the flags and target, so they don't step on each other. */
 546         instruction = 0x48000000 | (flags & 0x3) | (target & 0x03FFFFFC);
 547
 548         create_instruction(addr, instruction);
 549 }
 550
 551 static inline void create_function_call(unsigned long addr, void * func)
 552 {
 553         unsigned long func_addr;
 554
 555 #ifdef CONFIG_PPC64
 556         /*
 557          * On PPC64 the function pointer actually points to the function's
 558          * descriptor. The first entry in the descriptor is the address
 559          * of the function text.
 560          */
 561         func_addr = *(unsigned long *)func;
 562 #else
 563         func_addr = (unsigned long)func;
 564 #endif
 565         create_branch(addr, func_addr, BRANCH_SET_LINK);
 566 }
 567
 568 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
 569 extern void account_system_vtime(struct task_struct *);
 570 #endif
 571
 572 extern struct dentry *powerpc_debugfs_root;
 573
 574 #endif /* __KERNEL__ */
 575 #endif /* _ASM_POWERPC_SYSTEM_H */