arch/s390/include/asm/system.h

   1 /*
   2  * Copyright IBM Corp. 1999, 2009
   3  *
   4  * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
   5  */
   6
   7 #ifndef __ASM_SYSTEM_H
   8 #define __ASM_SYSTEM_H
   9
  10 #include <linux/kernel.h>
  11 #include <linux/errno.h>
  12 #include <asm/types.h>
  13 #include <asm/ptrace.h>
  14 #include <asm/setup.h>
  15 #include <asm/processor.h>
  16 #include <asm/lowcore.h>
  17
  18 #ifdef __KERNEL__
  19
  20 struct task_struct;
  21
  22 extern struct task_struct *__switch_to(void *, void *);
  23
  24 static inline void save_fp_regs(s390_fp_regs *fpregs)
  25 {
  26         asm volatile(
  27                 "       std     0,8(%1)\n"
  28                 "       std     2,24(%1)\n"
  29                 "       std     4,40(%1)\n"
  30                 "       std     6,56(%1)"
  31                 : "=m" (*fpregs) : "a" (fpregs), "m" (*fpregs) : "memory");
  32         if (!MACHINE_HAS_IEEE)
  33                 return;
  34         asm volatile(
  35                 "       stfpc   0(%1)\n"
  36                 "       std     1,16(%1)\n"
  37                 "       std     3,32(%1)\n"
  38                 "       std     5,48(%1)\n"
  39                 "       std     7,64(%1)\n"
  40                 "       std     8,72(%1)\n"
  41                 "       std     9,80(%1)\n"
  42                 "       std     10,88(%1)\n"
  43                 "       std     11,96(%1)\n"
  44                 "       std     12,104(%1)\n"
  45                 "       std     13,112(%1)\n"
  46                 "       std     14,120(%1)\n"
  47                 "       std     15,128(%1)\n"
  48                 : "=m" (*fpregs) : "a" (fpregs), "m" (*fpregs) : "memory");
  49 }
  50
  51 static inline void restore_fp_regs(s390_fp_regs *fpregs)
  52 {
  53         asm volatile(
  54                 "       ld      0,8(%0)\n"
  55                 "       ld      2,24(%0)\n"
  56                 "       ld      4,40(%0)\n"
  57                 "       ld      6,56(%0)"
  58                 : : "a" (fpregs), "m" (*fpregs));
  59         if (!MACHINE_HAS_IEEE)
  60                 return;
  61         asm volatile(
  62                 "       lfpc    0(%0)\n"
  63                 "       ld      1,16(%0)\n"
  64                 "       ld      3,32(%0)\n"
  65                 "       ld      5,48(%0)\n"
  66                 "       ld      7,64(%0)\n"
  67                 "       ld      8,72(%0)\n"
  68                 "       ld      9,80(%0)\n"
  69                 "       ld      10,88(%0)\n"
  70                 "       ld      11,96(%0)\n"
  71                 "       ld      12,104(%0)\n"
  72                 "       ld      13,112(%0)\n"
  73                 "       ld      14,120(%0)\n"
  74                 "       ld      15,128(%0)\n"
  75                 : : "a" (fpregs), "m" (*fpregs));
  76 }
  77
  78 static inline void save_access_regs(unsigned int *acrs)
  79 {
  80         asm volatile("stam 0,15,0(%0)" : : "a" (acrs) : "memory");
  81 }
  82
  83 static inline void restore_access_regs(unsigned int *acrs)
  84 {
  85         asm volatile("lam 0,15,0(%0)" : : "a" (acrs));
  86 }
  87
  88 #define switch_to(prev,next,last) do {                                       \
  89         if (prev == next)                                                    \
  90                 break;                                                       \
  91         save_fp_regs(&prev->thread.fp_regs);                                 \
  92         restore_fp_regs(&next->thread.fp_regs);                              \
  93         save_access_regs(&prev->thread.acrs[0]);                             \
  94         restore_access_regs(&next->thread.acrs[0]);                          \
  95         prev = __switch_to(prev,next);                                       \
  96 } while (0)
  97
  98 extern void account_vtime(struct task_struct *, struct task_struct *);
  99 extern void account_tick_vtime(struct task_struct *);
 100 extern void account_system_vtime(struct task_struct *);
 101
 102 #ifdef CONFIG_PFAULT
 103 extern void pfault_irq_init(void);
 104 extern int pfault_init(void);
 105 extern void pfault_fini(void);
 106 #else /* CONFIG_PFAULT */
 107 #define pfault_irq_init()       do { } while (0)
 108 #define pfault_init()           ({-1;})
 109 #define pfault_fini()           do { } while (0)
 110 #endif /* CONFIG_PFAULT */
 111
 112 #ifdef CONFIG_PAGE_STATES
 113 extern void cmma_init(void);
 114 #else
 115 static inline void cmma_init(void) { }
 116 #endif
 117
 118 #define finish_arch_switch(prev) do {                                        \
 119         set_fs(current->thread.mm_segment);                                  \
 120         account_vtime(prev, current);                                        \
 121 } while (0)
 122
 123 #define nop() asm volatile("nop")
 124
 125 #define xchg(ptr,x)                                                       \
 126 ({                                                                        \
 127         __typeof__(*(ptr)) __ret;                                         \
 128         __ret = (__typeof__(*(ptr)))                                      \
 129                 __xchg((unsigned long)(x), (void *)(ptr),sizeof(*(ptr))); \
 130         __ret;                                                            \
 131 })
 132
 133 extern void __xchg_called_with_bad_pointer(void);
 134
 135 static inline unsigned long __xchg(unsigned long x, void * ptr, int size)
 136 {
 137         unsigned long addr, old;
 138         int shift;
 139
 140         switch (size) {
 141         case 1:
 142                 addr = (unsigned long) ptr;
 143                 shift = (3 ^ (addr & 3)) << 3;
 144                 addr ^= addr & 3;
 145                 asm volatile(
 146                         "       l       %0,0(%4)\n"
 147                         "0:     lr      0,%0\n"
 148                         "       nr      0,%3\n"
 149                         "       or      0,%2\n"
 150                         "       cs      %0,0,0(%4)\n"
 151                         "       jl      0b\n"
 152                         : "=&d" (old), "=m" (*(int *) addr)
 153                         : "d" (x << shift), "d" (~(255 << shift)), "a" (addr),
 154                           "m" (*(int *) addr) : "memory", "cc", "0");
 155                 return old >> shift;
 156         case 2:
 157                 addr = (unsigned long) ptr;
 158                 shift = (2 ^ (addr & 2)) << 3;
 159                 addr ^= addr & 2;
 160                 asm volatile(
 161                         "       l       %0,0(%4)\n"
 162                         "0:     lr      0,%0\n"
 163                         "       nr      0,%3\n"
 164                         "       or      0,%2\n"
 165                         "       cs      %0,0,0(%4)\n"
 166                         "       jl      0b\n"
 167                         : "=&d" (old), "=m" (*(int *) addr)
 168                         : "d" (x << shift), "d" (~(65535 << shift)), "a" (addr),
 169                           "m" (*(int *) addr) : "memory", "cc", "0");
 170                 return old >> shift;
 171         case 4:
 172                 asm volatile(
 173                         "       l       %0,0(%3)\n"
 174                         "0:     cs      %0,%2,0(%3)\n"
 175                         "       jl      0b\n"
 176                         : "=&d" (old), "=m" (*(int *) ptr)
 177                         : "d" (x), "a" (ptr), "m" (*(int *) ptr)
 178                         : "memory", "cc");
 179                 return old;
 180 #ifdef __s390x__
 181         case 8:
 182                 asm volatile(
 183                         "       lg      %0,0(%3)\n"
 184                         "0:     csg     %0,%2,0(%3)\n"
 185                         "       jl      0b\n"
 186                         : "=&d" (old), "=m" (*(long *) ptr)
 187                         : "d" (x), "a" (ptr), "m" (*(long *) ptr)
 188                         : "memory", "cc");
 189                 return old;
 190 #endif /* __s390x__ */
 191         }
 192         __xchg_called_with_bad_pointer();
 193         return x;
 194 }
 195
 196 /*
 197  * Atomic compare and exchange.  Compare OLD with MEM, if identical,
 198  * store NEW in MEM.  Return the initial value in MEM.  Success is
 199  * indicated by comparing RETURN with OLD.
 200  */
 201
 202 #define __HAVE_ARCH_CMPXCHG 1
 203
 204 #define cmpxchg(ptr, o, n)                                              \
 205         ((__typeof__(*(ptr)))__cmpxchg((ptr), (unsigned long)(o),       \
 206                                         (unsigned long)(n), sizeof(*(ptr))))
 207
 208 extern void __cmpxchg_called_with_bad_pointer(void);
 209
 210 static inline unsigned long
 211 __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size)
 212 {
 213         unsigned long addr, prev, tmp;
 214         int shift;
 215
 216         switch (size) {
 217         case 1:
 218                 addr = (unsigned long) ptr;
 219                 shift = (3 ^ (addr & 3)) << 3;
 220                 addr ^= addr & 3;
 221                 asm volatile(
 222                         "       l       %0,0(%4)\n"
 223                         "0:     nr      %0,%5\n"
 224                         "       lr      %1,%0\n"
 225                         "       or      %0,%2\n"
 226                         "       or      %1,%3\n"
 227                         "       cs      %0,%1,0(%4)\n"
 228                         "       jnl     1f\n"
 229                         "       xr      %1,%0\n"
 230                         "       nr      %1,%5\n"
 231                         "       jnz     0b\n"
 232                         "1:"
 233                         : "=&d" (prev), "=&d" (tmp)
 234                         : "d" (old << shift), "d" (new << shift), "a" (ptr),
 235                           "d" (~(255 << shift))
 236                         : "memory", "cc");
 237                 return prev >> shift;
 238         case 2:
 239                 addr = (unsigned long) ptr;
 240                 shift = (2 ^ (addr & 2)) << 3;
 241                 addr ^= addr & 2;
 242                 asm volatile(
 243                         "       l       %0,0(%4)\n"
 244                         "0:     nr      %0,%5\n"
 245                         "       lr      %1,%0\n"
 246                         "       or      %0,%2\n"
 247                         "       or      %1,%3\n"
 248                         "       cs      %0,%1,0(%4)\n"
 249                         "       jnl     1f\n"
 250                         "       xr      %1,%0\n"
 251                         "       nr      %1,%5\n"
 252                         "       jnz     0b\n"
 253                         "1:"
 254                         : "=&d" (prev), "=&d" (tmp)
 255                         : "d" (old << shift), "d" (new << shift), "a" (ptr),
 256                           "d" (~(65535 << shift))
 257                         : "memory", "cc");
 258                 return prev >> shift;
 259         case 4:
 260                 asm volatile(
 261                         "       cs      %0,%2,0(%3)\n"
 262                         : "=&d" (prev) : "0" (old), "d" (new), "a" (ptr)
 263                         : "memory", "cc");
 264                 return prev;
 265 #ifdef __s390x__
 266         case 8:
 267                 asm volatile(
 268                         "       csg     %0,%2,0(%3)\n"
 269                         : "=&d" (prev) : "0" (old), "d" (new), "a" (ptr)
 270                         : "memory", "cc");
 271                 return prev;
 272 #endif /* __s390x__ */
 273         }
 274         __cmpxchg_called_with_bad_pointer();
 275         return old;
 276 }
 277
 278 /*
 279  * Force strict CPU ordering.
 280  * And yes, this is required on UP too when we're talking
 281  * to devices.
 282  *
 283  * This is very similar to the ppc eieio/sync instruction in that is
 284  * does a checkpoint syncronisation & makes sure that
 285  * all memory ops have completed wrt other CPU's ( see 7-15 POP  DJB ).
 286  */
 287
 288 #define eieio() asm volatile("bcr 15,0" : : : "memory")
 289 #define SYNC_OTHER_CORES(x)   eieio()
 290 #define mb()    eieio()
 291 #define rmb()   eieio()
 292 #define wmb()   eieio()
 293 #define read_barrier_depends() do { } while(0)
 294 #define smp_mb()       mb()
 295 #define smp_rmb()      rmb()
 296 #define smp_wmb()      wmb()
 297 #define smp_read_barrier_depends()    read_barrier_depends()
 298 #define smp_mb__before_clear_bit()     smp_mb()
 299 #define smp_mb__after_clear_bit()      smp_mb()
 300
 301
 302 #define set_mb(var, value)      do { var = value; mb(); } while (0)
 303
 304 #ifdef __s390x__
 305
 306 #define __ctl_load(array, low, high) ({                         \
 307         typedef struct { char _[sizeof(array)]; } addrtype;     \
 308         asm volatile(                                           \
 309                 "       lctlg   %1,%2,0(%0)\n"                  \
 310                 : : "a" (&array), "i" (low), "i" (high),        \
 311                     "m" (*(addrtype *)(&array)));               \
 312         })
 313
 314 #define __ctl_store(array, low, high) ({                        \
 315         typedef struct { char _[sizeof(array)]; } addrtype;     \
 316         asm volatile(                                           \
 317                 "       stctg   %2,%3,0(%1)\n"                  \
 318                 : "=m" (*(addrtype *)(&array))                  \
 319                 : "a" (&array), "i" (low), "i" (high));         \
 320         })
 321
 322 #else /* __s390x__ */
 323
 324 #define __ctl_load(array, low, high) ({                         \
 325         typedef struct { char _[sizeof(array)]; } addrtype;     \
 326         asm volatile(                                           \
 327                 "       lctl    %1,%2,0(%0)\n"                  \
 328                 : : "a" (&array), "i" (low), "i" (high),        \
 329                     "m" (*(addrtype *)(&array)));               \
 330 })
 331
 332 #define __ctl_store(array, low, high) ({                        \
 333         typedef struct { char _[sizeof(array)]; } addrtype;     \
 334         asm volatile(                                           \
 335                 "       stctl   %2,%3,0(%1)\n"                  \
 336                 : "=m" (*(addrtype *)(&array))                  \
 337                 : "a" (&array), "i" (low), "i" (high));         \
 338         })
 339
 340 #endif /* __s390x__ */
 341
 342 #define __ctl_set_bit(cr, bit) ({       \
 343         unsigned long __dummy;          \
 344         __ctl_store(__dummy, cr, cr);   \
 345         __dummy |= 1UL << (bit);        \
 346         __ctl_load(__dummy, cr, cr);    \
 347 })
 348
 349 #define __ctl_clear_bit(cr, bit) ({     \
 350         unsigned long __dummy;          \
 351         __ctl_store(__dummy, cr, cr);   \
 352         __dummy &= ~(1UL << (bit));     \
 353         __ctl_load(__dummy, cr, cr);    \
 354 })
 355
 356 #include <linux/irqflags.h>
 357
 358 #include <asm-generic/cmpxchg-local.h>
 359
 360 static inline unsigned long __cmpxchg_local(volatile void *ptr,
 361                                       unsigned long old,
 362                                       unsigned long new, int size)
 363 {
 364         switch (size) {
 365         case 1:
 366         case 2:
 367         case 4:
 368 #ifdef __s390x__
 369         case 8:
 370 #endif
 371                 return __cmpxchg(ptr, old, new, size);
 372         default:
 373                 return __cmpxchg_local_generic(ptr, old, new, size);
 374         }
 375
 376         return old;
 377 }
 378
 379 /*
 380  * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make
 381  * them available.
 382  */
 383 #define cmpxchg_local(ptr, o, n)                                        \
 384         ((__typeof__(*(ptr)))__cmpxchg_local((ptr), (unsigned long)(o), \
 385                         (unsigned long)(n), sizeof(*(ptr))))
 386 #ifdef __s390x__
 387 #define cmpxchg64_local(ptr, o, n)                                      \
 388   ({                                                                    \
 389         BUILD_BUG_ON(sizeof(*(ptr)) != 8);                              \
 390         cmpxchg_local((ptr), (o), (n));                                 \
 391   })
 392 #else
 393 #define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))
 394 #endif
 395
 396 /*
 397  * Use to set psw mask except for the first byte which
 398  * won't be changed by this function.
 399  */
 400 static inline void
 401 __set_psw_mask(unsigned long mask)
 402 {
 403         __load_psw_mask(mask | (__raw_local_irq_stosm(0x00) & ~(-1UL >> 8)));
 404 }
 405
 406 #define local_mcck_enable()  __set_psw_mask(psw_kernel_bits)
 407 #define local_mcck_disable() __set_psw_mask(psw_kernel_bits & ~PSW_MASK_MCHECK)
 408
 409 #ifdef CONFIG_SMP
 410
 411 extern void smp_ctl_set_bit(int cr, int bit);
 412 extern void smp_ctl_clear_bit(int cr, int bit);
 413 #define ctl_set_bit(cr, bit) smp_ctl_set_bit(cr, bit)
 414 #define ctl_clear_bit(cr, bit) smp_ctl_clear_bit(cr, bit)
 415
 416 #else
 417
 418 #define ctl_set_bit(cr, bit) __ctl_set_bit(cr, bit)
 419 #define ctl_clear_bit(cr, bit) __ctl_clear_bit(cr, bit)
 420
 421 #endif /* CONFIG_SMP */
 422
 423 static inline unsigned int stfl(void)
 424 {
 425         asm volatile(
 426                 "       .insn   s,0xb2b10000,0(0)\n" /* stfl */
 427                 "0:\n"
 428                 EX_TABLE(0b,0b));
 429         return S390_lowcore.stfl_fac_list;
 430 }
 431
 432 static inline int __stfle(unsigned long long *list, int doublewords)
 433 {
 434         typedef struct { unsigned long long _[doublewords]; } addrtype;
 435         register unsigned long __nr asm("0") = doublewords - 1;
 436
 437         asm volatile(".insn s,0xb2b00000,%0" /* stfle */
 438                      : "=m" (*(addrtype *) list), "+d" (__nr) : : "cc");
 439         return __nr + 1;
 440 }
 441
 442 static inline int stfle(unsigned long long *list, int doublewords)
 443 {
 444         if (!(stfl() & (1UL << 24)))
 445                 return -EOPNOTSUPP;
 446         return __stfle(list, doublewords);
 447 }
 448
 449 static inline unsigned short stap(void)
 450 {
 451         unsigned short cpu_address;
 452
 453         asm volatile("stap %0" : "=m" (cpu_address));
 454         return cpu_address;
 455 }
 456
 457 extern void (*_machine_restart)(char *command);
 458 extern void (*_machine_halt)(void);
 459 extern void (*_machine_power_off)(void);
 460
 461 #define arch_align_stack(x) (x)
 462
 463 #ifdef CONFIG_TRACE_IRQFLAGS
 464 extern psw_t sysc_restore_trace_psw;
 465 extern psw_t io_restore_trace_psw;
 466 #endif
 467
 468 static inline int tprot(unsigned long addr)
 469 {
 470         int rc = -EFAULT;
 471
 472         asm volatile(
 473                 "       tprot   0(%1),0\n"
 474                 "0:     ipm     %0\n"
 475                 "       srl     %0,28\n"
 476                 "1:\n"
 477                 EX_TABLE(0b,1b)
 478                 : "+d" (rc) : "a" (addr) : "cc");
 479         return rc;
 480 }
 481
 482 #endif /* __KERNEL__ */
 483
 484 #endif