include/asm-alpha/system.h

   1 #ifndef __ALPHA_SYSTEM_H
   2 #define __ALPHA_SYSTEM_H
   3
   4 #include <linux/config.h>
   5 #include <asm/pal.h>
   6 #include <asm/page.h>
   7
   8 /*
   9  * System defines.. Note that this is included both from .c and .S
  10  * files, so it does only defines, not any C code.
  11  */
  12
  13 /*
  14  * We leave one page for the initial stack page, and one page for
  15  * the initial process structure. Also, the console eats 3 MB for
  16  * the initial bootloader (one of which we can reclaim later).
  17  */
  18 #define BOOT_PCB        0x20000000
  19 #define BOOT_ADDR       0x20000000
  20 /* Remove when official MILO sources have ELF support: */
  21 #define BOOT_SIZE       (16*1024)
  22
  23 #ifdef CONFIG_ALPHA_LEGACY_START_ADDRESS
  24 #define KERNEL_START_PHYS       0x300000 /* Old bootloaders hardcoded this.  */
  25 #else
  26 #define KERNEL_START_PHYS       0x1000000 /* required: Wildfire/Titan/Marvel */
  27 #endif
  28
  29 #define KERNEL_START    (PAGE_OFFSET+KERNEL_START_PHYS)
  30 #define SWAPPER_PGD     KERNEL_START
  31 #define INIT_STACK      (PAGE_OFFSET+KERNEL_START_PHYS+0x02000)
  32 #define EMPTY_PGT       (PAGE_OFFSET+KERNEL_START_PHYS+0x04000)
  33 #define EMPTY_PGE       (PAGE_OFFSET+KERNEL_START_PHYS+0x08000)
  34 #define ZERO_PGE        (PAGE_OFFSET+KERNEL_START_PHYS+0x0A000)
  35
  36 #define START_ADDR      (PAGE_OFFSET+KERNEL_START_PHYS+0x10000)
  37
  38 /*
  39  * This is setup by the secondary bootstrap loader.  Because
  40  * the zero page is zeroed out as soon as the vm system is
  41  * initialized, we need to copy things out into a more permanent
  42  * place.
  43  */
  44 #define PARAM                   ZERO_PGE
  45 #define COMMAND_LINE            ((char*)(PARAM + 0x0000))
  46 #define INITRD_START            (*(unsigned long *) (PARAM+0x100))
  47 #define INITRD_SIZE             (*(unsigned long *) (PARAM+0x108))
  48
  49 #ifndef __ASSEMBLY__
  50 #include <linux/kernel.h>
  51
  52 /*
  53  * This is the logout header that should be common to all platforms
  54  * (assuming they are running OSF/1 PALcode, I guess).
  55  */
  56 struct el_common {
  57         unsigned int    size;           /* size in bytes of logout area */
  58         unsigned int    sbz1    : 30;   /* should be zero */
  59         unsigned int    err2    :  1;   /* second error */
  60         unsigned int    retry   :  1;   /* retry flag */
  61         unsigned int    proc_offset;    /* processor-specific offset */
  62         unsigned int    sys_offset;     /* system-specific offset */
  63         unsigned int    code;           /* machine check code */
  64         unsigned int    frame_rev;      /* frame revision */
  65 };
  66
  67 /* Machine Check Frame for uncorrectable errors (Large format)
  68  *      --- This is used to log uncorrectable errors such as
  69  *          double bit ECC errors.
  70  *      --- These errors are detected by both processor and systems.
  71  */
  72 struct el_common_EV5_uncorrectable_mcheck {
  73         unsigned long   shadow[8];        /* Shadow reg. 8-14, 25           */
  74         unsigned long   paltemp[24];      /* PAL TEMP REGS.                 */
  75         unsigned long   exc_addr;         /* Address of excepting instruction*/
  76         unsigned long   exc_sum;          /* Summary of arithmetic traps.   */
  77         unsigned long   exc_mask;         /* Exception mask (from exc_sum). */
  78         unsigned long   pal_base;         /* Base address for PALcode.      */
  79         unsigned long   isr;              /* Interrupt Status Reg.          */
  80         unsigned long   icsr;             /* CURRENT SETUP OF EV5 IBOX      */
  81         unsigned long   ic_perr_stat;     /* I-CACHE Reg. <11> set Data parity
  82                                                          <12> set TAG parity*/
  83         unsigned long   dc_perr_stat;     /* D-CACHE error Reg. Bits set to 1:
  84                                                      <2> Data error in bank 0
  85                                                      <3> Data error in bank 1
  86                                                      <4> Tag error in bank 0
  87                                                      <5> Tag error in bank 1 */
  88         unsigned long   va;               /* Effective VA of fault or miss. */
  89         unsigned long   mm_stat;          /* Holds the reason for D-stream
  90                                              fault or D-cache parity errors */
  91         unsigned long   sc_addr;          /* Address that was being accessed
  92                                              when EV5 detected Secondary cache
  93                                              failure.                 */
  94         unsigned long   sc_stat;          /* Helps determine if the error was
  95                                              TAG/Data parity(Secondary Cache)*/
  96         unsigned long   bc_tag_addr;      /* Contents of EV5 BC_TAG_ADDR    */
  97         unsigned long   ei_addr;          /* Physical address of any transfer
  98                                              that is logged in EV5 EI_STAT */
  99         unsigned long   fill_syndrome;    /* For correcting ECC errors.     */
 100         unsigned long   ei_stat;          /* Helps identify reason of any
 101                                              processor uncorrectable error
 102                                              at its external interface.     */
 103         unsigned long   ld_lock;          /* Contents of EV5 LD_LOCK register*/
 104 };
 105
 106 struct el_common_EV6_mcheck {
 107         unsigned int FrameSize;         /* Bytes, including this field */
 108         unsigned int FrameFlags;        /* <31> = Retry, <30> = Second Error */
 109         unsigned int CpuOffset;         /* Offset to CPU-specific info */
 110         unsigned int SystemOffset;      /* Offset to system-specific info */
 111         unsigned int MCHK_Code;
 112         unsigned int MCHK_Frame_Rev;
 113         unsigned long I_STAT;           /* EV6 Internal Processor Registers */
 114         unsigned long DC_STAT;          /* (See the 21264 Spec) */
 115         unsigned long C_ADDR;
 116         unsigned long DC1_SYNDROME;
 117         unsigned long DC0_SYNDROME;
 118         unsigned long C_STAT;
 119         unsigned long C_STS;
 120         unsigned long MM_STAT;
 121         unsigned long EXC_ADDR;
 122         unsigned long IER_CM;
 123         unsigned long ISUM;
 124         unsigned long RESERVED0;
 125         unsigned long PAL_BASE;
 126         unsigned long I_CTL;
 127         unsigned long PCTX;
 128 };
 129
 130 extern void halt(void) __attribute__((noreturn));
 131 #define __halt() __asm__ __volatile__ ("call_pal %0 #halt" : : "i" (PAL_halt))
 132
 133 #define switch_to(P,N,L)                                                \
 134   do {                                                                  \
 135     (L) = alpha_switch_to(virt_to_phys(&(N)->thread_info->pcb), (P));   \
 136     check_mmu_context();                                                \
 137   } while (0)
 138
 139 struct task_struct;
 140 extern struct task_struct *alpha_switch_to(unsigned long, struct task_struct*);
 141
 142 #define mb() \
 143 __asm__ __volatile__("mb": : :"memory")
 144
 145 #define rmb() \
 146 __asm__ __volatile__("mb": : :"memory")
 147
 148 #define wmb() \
 149 __asm__ __volatile__("wmb": : :"memory")
 150
 151 #define read_barrier_depends() \
 152 __asm__ __volatile__("mb": : :"memory")
 153
 154 #ifdef CONFIG_SMP
 155 #define smp_mb()        mb()
 156 #define smp_rmb()       rmb()
 157 #define smp_wmb()       wmb()
 158 #define smp_read_barrier_depends()      read_barrier_depends()
 159 #else
 160 #define smp_mb()        barrier()
 161 #define smp_rmb()       barrier()
 162 #define smp_wmb()       barrier()
 163 #define smp_read_barrier_depends()      barrier()
 164 #endif
 165
 166 #define set_mb(var, value) \
 167 do { var = value; mb(); } while (0)
 168
 169 #define set_wmb(var, value) \
 170 do { var = value; wmb(); } while (0)
 171
 172 #define imb() \
 173 __asm__ __volatile__ ("call_pal %0 #imb" : : "i" (PAL_imb) : "memory")
 174
 175 #define draina() \
 176 __asm__ __volatile__ ("call_pal %0 #draina" : : "i" (PAL_draina) : "memory")
 177
 178 enum implver_enum {
 179         IMPLVER_EV4,
 180         IMPLVER_EV5,
 181         IMPLVER_EV6
 182 };
 183
 184 #ifdef CONFIG_ALPHA_GENERIC
 185 #define implver()                               \
 186 ({ unsigned long __implver;                     \
 187    __asm__ ("implver %0" : "=r"(__implver));    \
 188    (enum implver_enum) __implver; })
 189 #else
 190 /* Try to eliminate some dead code.  */
 191 #ifdef CONFIG_ALPHA_EV4
 192 #define implver() IMPLVER_EV4
 193 #endif
 194 #ifdef CONFIG_ALPHA_EV5
 195 #define implver() IMPLVER_EV5
 196 #endif
 197 #if defined(CONFIG_ALPHA_EV6)
 198 #define implver() IMPLVER_EV6
 199 #endif
 200 #endif
 201
 202 enum amask_enum {
 203         AMASK_BWX = (1UL << 0),
 204         AMASK_FIX = (1UL << 1),
 205         AMASK_CIX = (1UL << 2),
 206         AMASK_MAX = (1UL << 8),
 207         AMASK_PRECISE_TRAP = (1UL << 9),
 208 };
 209
 210 #define amask(mask)                                             \
 211 ({ unsigned long __amask, __input = (mask);                     \
 212    __asm__ ("amask %1,%0" : "=r"(__amask) : "rI"(__input));     \
 213    __amask; })
 214
 215 #define __CALL_PAL_R0(NAME, TYPE)                               \
 216 static inline TYPE NAME(void)                                   \
 217 {                                                               \
 218         register TYPE __r0 __asm__("$0");                       \
 219         __asm__ __volatile__(                                   \
 220                 "call_pal %1 # " #NAME                          \
 221                 :"=r" (__r0)                                    \
 222                 :"i" (PAL_ ## NAME)                             \
 223                 :"$1", "$16", "$22", "$23", "$24", "$25");      \
 224         return __r0;                                            \
 225 }
 226
 227 #define __CALL_PAL_W1(NAME, TYPE0)                              \
 228 static inline void NAME(TYPE0 arg0)                             \
 229 {                                                               \
 230         register TYPE0 __r16 __asm__("$16") = arg0;             \
 231         __asm__ __volatile__(                                   \
 232                 "call_pal %1 # "#NAME                           \
 233                 : "=r"(__r16)                                   \
 234                 : "i"(PAL_ ## NAME), "0"(__r16)                 \
 235                 : "$1", "$22", "$23", "$24", "$25");            \
 236 }
 237
 238 #define __CALL_PAL_W2(NAME, TYPE0, TYPE1)                       \
 239 static inline void NAME(TYPE0 arg0, TYPE1 arg1)                 \
 240 {                                                               \
 241         register TYPE0 __r16 __asm__("$16") = arg0;             \
 242         register TYPE1 __r17 __asm__("$17") = arg1;             \
 243         __asm__ __volatile__(                                   \
 244                 "call_pal %2 # "#NAME                           \
 245                 : "=r"(__r16), "=r"(__r17)                      \
 246                 : "i"(PAL_ ## NAME), "0"(__r16), "1"(__r17)     \
 247                 : "$1", "$22", "$23", "$24", "$25");            \
 248 }
 249
 250 #define __CALL_PAL_RW1(NAME, RTYPE, TYPE0)                      \
 251 static inline RTYPE NAME(TYPE0 arg0)                            \
 252 {                                                               \
 253         register RTYPE __r0 __asm__("$0");                      \
 254         register TYPE0 __r16 __asm__("$16") = arg0;             \
 255         __asm__ __volatile__(                                   \
 256                 "call_pal %2 # "#NAME                           \
 257                 : "=r"(__r16), "=r"(__r0)                       \
 258                 : "i"(PAL_ ## NAME), "0"(__r16)                 \
 259                 : "$1", "$22", "$23", "$24", "$25");            \
 260         return __r0;                                            \
 261 }
 262
 263 #define __CALL_PAL_RW2(NAME, RTYPE, TYPE0, TYPE1)               \
 264 static inline RTYPE NAME(TYPE0 arg0, TYPE1 arg1)                \
 265 {                                                               \
 266         register RTYPE __r0 __asm__("$0");                      \
 267         register TYPE0 __r16 __asm__("$16") = arg0;             \
 268         register TYPE1 __r17 __asm__("$17") = arg1;             \
 269         __asm__ __volatile__(                                   \
 270                 "call_pal %3 # "#NAME                           \
 271                 : "=r"(__r16), "=r"(__r17), "=r"(__r0)          \
 272                 : "i"(PAL_ ## NAME), "0"(__r16), "1"(__r17)     \
 273                 : "$1", "$22", "$23", "$24", "$25");            \
 274         return __r0;                                            \
 275 }
 276
 277 __CALL_PAL_W1(cflush, unsigned long);
 278 __CALL_PAL_R0(rdmces, unsigned long);
 279 __CALL_PAL_R0(rdps, unsigned long);
 280 __CALL_PAL_R0(rdusp, unsigned long);
 281 __CALL_PAL_RW1(swpipl, unsigned long, unsigned long);
 282 __CALL_PAL_R0(whami, unsigned long);
 283 __CALL_PAL_W2(wrent, void*, unsigned long);
 284 __CALL_PAL_W1(wripir, unsigned long);
 285 __CALL_PAL_W1(wrkgp, unsigned long);
 286 __CALL_PAL_W1(wrmces, unsigned long);
 287 __CALL_PAL_RW2(wrperfmon, unsigned long, unsigned long, unsigned long);
 288 __CALL_PAL_W1(wrusp, unsigned long);
 289 __CALL_PAL_W1(wrvptptr, unsigned long);
 290
 291 #define IPL_MIN         0
 292 #define IPL_SW0         1
 293 #define IPL_SW1         2
 294 #define IPL_DEV0        3
 295 #define IPL_DEV1        4
 296 #define IPL_TIMER       5
 297 #define IPL_PERF        6
 298 #define IPL_POWERFAIL   6
 299 #define IPL_MCHECK      7
 300 #define IPL_MAX         7
 301
 302 #ifdef CONFIG_ALPHA_BROKEN_IRQ_MASK
 303 #undef IPL_MIN
 304 #define IPL_MIN         __min_ipl
 305 extern int __min_ipl;
 306 #endif
 307
 308 #define getipl()                (rdps() & 7)
 309 #define setipl(ipl)             ((void) swpipl(ipl))
 310
 311 #define local_irq_disable()                     do { setipl(IPL_MAX); barrier(); } while(0)
 312 #define local_irq_enable()                      do { barrier(); setipl(IPL_MIN); } while(0)
 313 #define local_save_flags(flags) ((flags) = rdps())
 314 #define local_irq_save(flags)   do { (flags) = swpipl(IPL_MAX); barrier(); } while(0)
 315 #define local_irq_restore(flags)        do { barrier(); setipl(flags); barrier(); } while(0)
 316
 317 #define irqs_disabled() (getipl() == IPL_MAX)
 318
 319 /*
 320  * TB routines..
 321  */
 322 #define __tbi(nr,arg,arg1...)                                   \
 323 ({                                                              \
 324         register unsigned long __r16 __asm__("$16") = (nr);     \
 325         register unsigned long __r17 __asm__("$17"); arg;       \
 326         __asm__ __volatile__(                                   \
 327                 "call_pal %3 #__tbi"                            \
 328                 :"=r" (__r16),"=r" (__r17)                      \
 329                 :"0" (__r16),"i" (PAL_tbi) ,##arg1              \
 330                 :"$0", "$1", "$22", "$23", "$24", "$25");       \
 331 })
 332
 333 #define tbi(x,y)        __tbi(x,__r17=(y),"1" (__r17))
 334 #define tbisi(x)        __tbi(1,__r17=(x),"1" (__r17))
 335 #define tbisd(x)        __tbi(2,__r17=(x),"1" (__r17))
 336 #define tbis(x)         __tbi(3,__r17=(x),"1" (__r17))
 337 #define tbiap()         __tbi(-1, /* no second argument */)
 338 #define tbia()          __tbi(-2, /* no second argument */)
 339
 340 /*
 341  * Atomic exchange.
 342  * Since it can be used to implement critical sections
 343  * it must clobber "memory" (also for interrupts in UP).
 344  */
 345
 346 static inline unsigned long
 347 __xchg_u8(volatile char *m, unsigned long val)
 348 {
 349         unsigned long ret, tmp, addr64;
 350
 351         __asm__ __volatile__(
 352         "       andnot  %4,7,%3\n"
 353         "       insbl   %1,%4,%1\n"
 354         "1:     ldq_l   %2,0(%3)\n"
 355         "       extbl   %2,%4,%0\n"
 356         "       mskbl   %2,%4,%2\n"
 357         "       or      %1,%2,%2\n"
 358         "       stq_c   %2,0(%3)\n"
 359         "       beq     %2,2f\n"
 360 #ifdef CONFIG_SMP
 361         "       mb\n"
 362 #endif
 363         ".subsection 2\n"
 364         "2:     br      1b\n"
 365         ".previous"
 366         : "=&r" (ret), "=&r" (val), "=&r" (tmp), "=&r" (addr64)
 367         : "r" ((long)m), "1" (val) : "memory");
 368
 369         return ret;
 370 }
 371
 372 static inline unsigned long
 373 __xchg_u16(volatile short *m, unsigned long val)
 374 {
 375         unsigned long ret, tmp, addr64;
 376
 377         __asm__ __volatile__(
 378         "       andnot  %4,7,%3\n"
 379         "       inswl   %1,%4,%1\n"
 380         "1:     ldq_l   %2,0(%3)\n"
 381         "       extwl   %2,%4,%0\n"
 382         "       mskwl   %2,%4,%2\n"
 383         "       or      %1,%2,%2\n"
 384         "       stq_c   %2,0(%3)\n"
 385         "       beq     %2,2f\n"
 386 #ifdef CONFIG_SMP
 387         "       mb\n"
 388 #endif
 389         ".subsection 2\n"
 390         "2:     br      1b\n"
 391         ".previous"
 392         : "=&r" (ret), "=&r" (val), "=&r" (tmp), "=&r" (addr64)
 393         : "r" ((long)m), "1" (val) : "memory");
 394
 395         return ret;
 396 }
 397
 398 static inline unsigned long
 399 __xchg_u32(volatile int *m, unsigned long val)
 400 {
 401         unsigned long dummy;
 402
 403         __asm__ __volatile__(
 404         "1:     ldl_l %0,%4\n"
 405         "       bis $31,%3,%1\n"
 406         "       stl_c %1,%2\n"
 407         "       beq %1,2f\n"
 408 #ifdef CONFIG_SMP
 409         "       mb\n"
 410 #endif
 411         ".subsection 2\n"
 412         "2:     br 1b\n"
 413         ".previous"
 414         : "=&r" (val), "=&r" (dummy), "=m" (*m)
 415         : "rI" (val), "m" (*m) : "memory");
 416
 417         return val;
 418 }
 419
 420 static inline unsigned long
 421 __xchg_u64(volatile long *m, unsigned long val)
 422 {
 423         unsigned long dummy;
 424
 425         __asm__ __volatile__(
 426         "1:     ldq_l %0,%4\n"
 427         "       bis $31,%3,%1\n"
 428         "       stq_c %1,%2\n"
 429         "       beq %1,2f\n"
 430 #ifdef CONFIG_SMP
 431         "       mb\n"
 432 #endif
 433         ".subsection 2\n"
 434         "2:     br 1b\n"
 435         ".previous"
 436         : "=&r" (val), "=&r" (dummy), "=m" (*m)
 437         : "rI" (val), "m" (*m) : "memory");
 438
 439         return val;
 440 }
 441
 442 /* This function doesn't exist, so you'll get a linker error
 443    if something tries to do an invalid xchg().  */
 444 extern void __xchg_called_with_bad_pointer(void);
 445
 446 static inline unsigned long
 447 __xchg(volatile void *ptr, unsigned long x, int size)
 448 {
 449         switch (size) {
 450                 case 1:
 451                         return __xchg_u8(ptr, x);
 452                 case 2:
 453                         return __xchg_u16(ptr, x);
 454                 case 4:
 455                         return __xchg_u32(ptr, x);
 456                 case 8:
 457                         return __xchg_u64(ptr, x);
 458         }
 459         __xchg_called_with_bad_pointer();
 460         return x;
 461 }
 462
 463 #define xchg(ptr,x)                                                          \
 464   ({                                                                         \
 465      __typeof__(*(ptr)) _x_ = (x);                                           \
 466      (__typeof__(*(ptr))) __xchg((ptr), (unsigned long)_x_, sizeof(*(ptr))); \
 467   })
 468
 469 #define tas(ptr) (xchg((ptr),1))
 470
 471
 472 /*
 473  * Atomic compare and exchange.  Compare OLD with MEM, if identical,
 474  * store NEW in MEM.  Return the initial value in MEM.  Success is
 475  * indicated by comparing RETURN with OLD.
 476  *
 477  * The memory barrier should be placed in SMP only when we actually
 478  * make the change. If we don't change anything (so if the returned
 479  * prev is equal to old) then we aren't acquiring anything new and
 480  * we don't need any memory barrier as far I can tell.
 481  */
 482
 483 #define __HAVE_ARCH_CMPXCHG 1
 484
 485 static inline unsigned long
 486 __cmpxchg_u8(volatile char *m, long old, long new)
 487 {
 488         unsigned long prev, tmp, cmp, addr64;
 489
 490         __asm__ __volatile__(
 491         "       andnot  %5,7,%4\n"
 492         "       insbl   %1,%5,%1\n"
 493         "1:     ldq_l   %2,0(%4)\n"
 494         "       extbl   %2,%5,%0\n"
 495         "       cmpeq   %0,%6,%3\n"
 496         "       beq     %3,2f\n"
 497         "       mskbl   %2,%5,%2\n"
 498         "       or      %1,%2,%2\n"
 499         "       stq_c   %2,0(%4)\n"
 500         "       beq     %2,3f\n"
 501 #ifdef CONFIG_SMP
 502         "       mb\n"
 503 #endif
 504         "2:\n"
 505         ".subsection 2\n"
 506         "3:     br      1b\n"
 507         ".previous"
 508         : "=&r" (prev), "=&r" (new), "=&r" (tmp), "=&r" (cmp), "=&r" (addr64)
 509         : "r" ((long)m), "Ir" (old), "1" (new) : "memory");
 510
 511         return prev;
 512 }
 513
 514 static inline unsigned long
 515 __cmpxchg_u16(volatile short *m, long old, long new)
 516 {
 517         unsigned long prev, tmp, cmp, addr64;
 518
 519         __asm__ __volatile__(
 520         "       andnot  %5,7,%4\n"
 521         "       inswl   %1,%5,%1\n"
 522         "1:     ldq_l   %2,0(%4)\n"
 523         "       extwl   %2,%5,%0\n"
 524         "       cmpeq   %0,%6,%3\n"
 525         "       beq     %3,2f\n"
 526         "       mskwl   %2,%5,%2\n"
 527         "       or      %1,%2,%2\n"
 528         "       stq_c   %2,0(%4)\n"
 529         "       beq     %2,3f\n"
 530 #ifdef CONFIG_SMP
 531         "       mb\n"
 532 #endif
 533         "2:\n"
 534         ".subsection 2\n"
 535         "3:     br      1b\n"
 536         ".previous"
 537         : "=&r" (prev), "=&r" (new), "=&r" (tmp), "=&r" (cmp), "=&r" (addr64)
 538         : "r" ((long)m), "Ir" (old), "1" (new) : "memory");
 539
 540         return prev;
 541 }
 542
 543 static inline unsigned long
 544 __cmpxchg_u32(volatile int *m, int old, int new)
 545 {
 546         unsigned long prev, cmp;
 547
 548         __asm__ __volatile__(
 549         "1:     ldl_l %0,%5\n"
 550         "       cmpeq %0,%3,%1\n"
 551         "       beq %1,2f\n"
 552         "       mov %4,%1\n"
 553         "       stl_c %1,%2\n"
 554         "       beq %1,3f\n"
 555 #ifdef CONFIG_SMP
 556         "       mb\n"
 557 #endif
 558         "2:\n"
 559         ".subsection 2\n"
 560         "3:     br 1b\n"
 561         ".previous"
 562         : "=&r"(prev), "=&r"(cmp), "=m"(*m)
 563         : "r"((long) old), "r"(new), "m"(*m) : "memory");
 564
 565         return prev;
 566 }
 567
 568 static inline unsigned long
 569 __cmpxchg_u64(volatile long *m, unsigned long old, unsigned long new)
 570 {
 571         unsigned long prev, cmp;
 572
 573         __asm__ __volatile__(
 574         "1:     ldq_l %0,%5\n"
 575         "       cmpeq %0,%3,%1\n"
 576         "       beq %1,2f\n"
 577         "       mov %4,%1\n"
 578         "       stq_c %1,%2\n"
 579         "       beq %1,3f\n"
 580 #ifdef CONFIG_SMP
 581         "       mb\n"
 582 #endif
 583         "2:\n"
 584         ".subsection 2\n"
 585         "3:     br 1b\n"
 586         ".previous"
 587         : "=&r"(prev), "=&r"(cmp), "=m"(*m)
 588         : "r"((long) old), "r"(new), "m"(*m) : "memory");
 589
 590         return prev;
 591 }
 592
 593 /* This function doesn't exist, so you'll get a linker error
 594    if something tries to do an invalid cmpxchg().  */
 595 extern void __cmpxchg_called_with_bad_pointer(void);
 596
 597 static inline unsigned long
 598 __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size)
 599 {
 600         switch (size) {
 601                 case 1:
 602                         return __cmpxchg_u8(ptr, old, new);
 603                 case 2:
 604                         return __cmpxchg_u16(ptr, old, new);
 605                 case 4:
 606                         return __cmpxchg_u32(ptr, old, new);
 607                 case 8:
 608                         return __cmpxchg_u64(ptr, old, new);
 609         }
 610         __cmpxchg_called_with_bad_pointer();
 611         return old;
 612 }
 613
 614 #define cmpxchg(ptr,o,n)                                                 \
 615   ({                                                                     \
 616      __typeof__(*(ptr)) _o_ = (o);                                       \
 617      __typeof__(*(ptr)) _n_ = (n);                                       \
 618      (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_,           \
 619                                     (unsigned long)_n_, sizeof(*(ptr))); \
 620   })
 621
 622 #endif /* __ASSEMBLY__ */
 623
 624 #define arch_align_stack(x) (x)
 625
 626 #endif