include/asm-s390/system.h

   1 /*
   2  *  include/asm-s390/system.h
   3  *
   4  *  S390 version
   5  *    Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
   6  *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
   7  *
   8  *  Derived from "include/asm-i386/system.h"
   9  */
  10
  11 #ifndef __ASM_SYSTEM_H
  12 #define __ASM_SYSTEM_H
  13
  14 #include <linux/kernel.h>
  15 #include <asm/types.h>
  16 #include <asm/ptrace.h>
  17 #include <asm/setup.h>
  18 #include <asm/processor.h>
  19 #include <asm/lowcore.h>
  20
  21 #ifdef __KERNEL__
  22
  23 struct task_struct;
  24
  25 extern struct task_struct *__switch_to(void *, void *);
  26
  27 static inline void save_fp_regs(s390_fp_regs *fpregs)
  28 {
  29         asm volatile(
  30                 "       std     0,8(%1)\n"
  31                 "       std     2,24(%1)\n"
  32                 "       std     4,40(%1)\n"
  33                 "       std     6,56(%1)"
  34                 : "=m" (*fpregs) : "a" (fpregs), "m" (*fpregs) : "memory");
  35         if (!MACHINE_HAS_IEEE)
  36                 return;
  37         asm volatile(
  38                 "       stfpc   0(%1)\n"
  39                 "       std     1,16(%1)\n"
  40                 "       std     3,32(%1)\n"
  41                 "       std     5,48(%1)\n"
  42                 "       std     7,64(%1)\n"
  43                 "       std     8,72(%1)\n"
  44                 "       std     9,80(%1)\n"
  45                 "       std     10,88(%1)\n"
  46                 "       std     11,96(%1)\n"
  47                 "       std     12,104(%1)\n"
  48                 "       std     13,112(%1)\n"
  49                 "       std     14,120(%1)\n"
  50                 "       std     15,128(%1)\n"
  51                 : "=m" (*fpregs) : "a" (fpregs), "m" (*fpregs) : "memory");
  52 }
  53
  54 static inline void restore_fp_regs(s390_fp_regs *fpregs)
  55 {
  56         asm volatile(
  57                 "       ld      0,8(%0)\n"
  58                 "       ld      2,24(%0)\n"
  59                 "       ld      4,40(%0)\n"
  60                 "       ld      6,56(%0)"
  61                 : : "a" (fpregs), "m" (*fpregs));
  62         if (!MACHINE_HAS_IEEE)
  63                 return;
  64         asm volatile(
  65                 "       lfpc    0(%0)\n"
  66                 "       ld      1,16(%0)\n"
  67                 "       ld      3,32(%0)\n"
  68                 "       ld      5,48(%0)\n"
  69                 "       ld      7,64(%0)\n"
  70                 "       ld      8,72(%0)\n"
  71                 "       ld      9,80(%0)\n"
  72                 "       ld      10,88(%0)\n"
  73                 "       ld      11,96(%0)\n"
  74                 "       ld      12,104(%0)\n"
  75                 "       ld      13,112(%0)\n"
  76                 "       ld      14,120(%0)\n"
  77                 "       ld      15,128(%0)\n"
  78                 : : "a" (fpregs), "m" (*fpregs));
  79 }
  80
  81 static inline void save_access_regs(unsigned int *acrs)
  82 {
  83         asm volatile("stam 0,15,0(%0)" : : "a" (acrs) : "memory");
  84 }
  85
  86 static inline void restore_access_regs(unsigned int *acrs)
  87 {
  88         asm volatile("lam 0,15,0(%0)" : : "a" (acrs));
  89 }
  90
  91 #define switch_to(prev,next,last) do {                                       \
  92         if (prev == next)                                                    \
  93                 break;                                                       \
  94         save_fp_regs(&prev->thread.fp_regs);                                 \
  95         restore_fp_regs(&next->thread.fp_regs);                              \
  96         save_access_regs(&prev->thread.acrs[0]);                             \
  97         restore_access_regs(&next->thread.acrs[0]);                          \
  98         prev = __switch_to(prev,next);                                       \
  99 } while (0)
 100
 101 #ifdef CONFIG_VIRT_CPU_ACCOUNTING
 102 extern void account_vtime(struct task_struct *);
 103 extern void account_tick_vtime(struct task_struct *);
 104 extern void account_system_vtime(struct task_struct *);
 105 #else
 106 #define account_vtime(x) do { /* empty */ } while (0)
 107 #endif
 108
 109 #ifdef CONFIG_PFAULT
 110 extern void pfault_irq_init(void);
 111 extern int pfault_init(void);
 112 extern void pfault_fini(void);
 113 #else /* CONFIG_PFAULT */
 114 #define pfault_irq_init()       do { } while (0)
 115 #define pfault_init()           ({-1;})
 116 #define pfault_fini()           do { } while (0)
 117 #endif /* CONFIG_PFAULT */
 118
 119 #define finish_arch_switch(prev) do {                                        \
 120         set_fs(current->thread.mm_segment);                                  \
 121         account_vtime(prev);                                                 \
 122 } while (0)
 123
 124 #define nop() asm volatile("nop")
 125
 126 #define xchg(ptr,x)                                                       \
 127 ({                                                                        \
 128         __typeof__(*(ptr)) __ret;                                         \
 129         __ret = (__typeof__(*(ptr)))                                      \
 130                 __xchg((unsigned long)(x), (void *)(ptr),sizeof(*(ptr))); \
 131         __ret;                                                            \
 132 })
 133
 134 extern void __xchg_called_with_bad_pointer(void);
 135
 136 static inline unsigned long __xchg(unsigned long x, void * ptr, int size)
 137 {
 138         unsigned long addr, old;
 139         int shift;
 140
 141         switch (size) {
 142         case 1:
 143                 addr = (unsigned long) ptr;
 144                 shift = (3 ^ (addr & 3)) << 3;
 145                 addr ^= addr & 3;
 146                 asm volatile(
 147                         "       l       %0,0(%4)\n"
 148                         "0:     lr      0,%0\n"
 149                         "       nr      0,%3\n"
 150                         "       or      0,%2\n"
 151                         "       cs      %0,0,0(%4)\n"
 152                         "       jl      0b\n"
 153                         : "=&d" (old), "=m" (*(int *) addr)
 154                         : "d" (x << shift), "d" (~(255 << shift)), "a" (addr),
 155                           "m" (*(int *) addr) : "memory", "cc", "0");
 156                 return old >> shift;
 157         case 2:
 158                 addr = (unsigned long) ptr;
 159                 shift = (2 ^ (addr & 2)) << 3;
 160                 addr ^= addr & 2;
 161                 asm volatile(
 162                         "       l       %0,0(%4)\n"
 163                         "0:     lr      0,%0\n"
 164                         "       nr      0,%3\n"
 165                         "       or      0,%2\n"
 166                         "       cs      %0,0,0(%4)\n"
 167                         "       jl      0b\n"
 168                         : "=&d" (old), "=m" (*(int *) addr)
 169                         : "d" (x << shift), "d" (~(65535 << shift)), "a" (addr),
 170                           "m" (*(int *) addr) : "memory", "cc", "0");
 171                 return old >> shift;
 172         case 4:
 173                 asm volatile(
 174                         "       l       %0,0(%3)\n"
 175                         "0:     cs      %0,%2,0(%3)\n"
 176                         "       jl      0b\n"
 177                         : "=&d" (old), "=m" (*(int *) ptr)
 178                         : "d" (x), "a" (ptr), "m" (*(int *) ptr)
 179                         : "memory", "cc");
 180                 return old;
 181 #ifdef __s390x__
 182         case 8:
 183                 asm volatile(
 184                         "       lg      %0,0(%3)\n"
 185                         "0:     csg     %0,%2,0(%3)\n"
 186                         "       jl      0b\n"
 187                         : "=&d" (old), "=m" (*(long *) ptr)
 188                         : "d" (x), "a" (ptr), "m" (*(long *) ptr)
 189                         : "memory", "cc");
 190                 return old;
 191 #endif /* __s390x__ */
 192         }
 193         __xchg_called_with_bad_pointer();
 194         return x;
 195 }
 196
 197 /*
 198  * Atomic compare and exchange.  Compare OLD with MEM, if identical,
 199  * store NEW in MEM.  Return the initial value in MEM.  Success is
 200  * indicated by comparing RETURN with OLD.
 201  */
 202
 203 #define __HAVE_ARCH_CMPXCHG 1
 204
 205 #define cmpxchg(ptr, o, n)                                              \
 206         ((__typeof__(*(ptr)))__cmpxchg((ptr), (unsigned long)(o),       \
 207                                         (unsigned long)(n), sizeof(*(ptr))))
 208
 209 extern void __cmpxchg_called_with_bad_pointer(void);
 210
 211 static inline unsigned long
 212 __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size)
 213 {
 214         unsigned long addr, prev, tmp;
 215         int shift;
 216
 217         switch (size) {
 218         case 1:
 219                 addr = (unsigned long) ptr;
 220                 shift = (3 ^ (addr & 3)) << 3;
 221                 addr ^= addr & 3;
 222                 asm volatile(
 223                         "       l       %0,0(%4)\n"
 224                         "0:     nr      %0,%5\n"
 225                         "       lr      %1,%0\n"
 226                         "       or      %0,%2\n"
 227                         "       or      %1,%3\n"
 228                         "       cs      %0,%1,0(%4)\n"
 229                         "       jnl     1f\n"
 230                         "       xr      %1,%0\n"
 231                         "       nr      %1,%5\n"
 232                         "       jnz     0b\n"
 233                         "1:"
 234                         : "=&d" (prev), "=&d" (tmp)
 235                         : "d" (old << shift), "d" (new << shift), "a" (ptr),
 236                           "d" (~(255 << shift))
 237                         : "memory", "cc");
 238                 return prev >> shift;
 239         case 2:
 240                 addr = (unsigned long) ptr;
 241                 shift = (2 ^ (addr & 2)) << 3;
 242                 addr ^= addr & 2;
 243                 asm volatile(
 244                         "       l       %0,0(%4)\n"
 245                         "0:     nr      %0,%5\n"
 246                         "       lr      %1,%0\n"
 247                         "       or      %0,%2\n"
 248                         "       or      %1,%3\n"
 249                         "       cs      %0,%1,0(%4)\n"
 250                         "       jnl     1f\n"
 251                         "       xr      %1,%0\n"
 252                         "       nr      %1,%5\n"
 253                         "       jnz     0b\n"
 254                         "1:"
 255                         : "=&d" (prev), "=&d" (tmp)
 256                         : "d" (old << shift), "d" (new << shift), "a" (ptr),
 257                           "d" (~(65535 << shift))
 258                         : "memory", "cc");
 259                 return prev >> shift;
 260         case 4:
 261                 asm volatile(
 262                         "       cs      %0,%2,0(%3)\n"
 263                         : "=&d" (prev) : "0" (old), "d" (new), "a" (ptr)
 264                         : "memory", "cc");
 265                 return prev;
 266 #ifdef __s390x__
 267         case 8:
 268                 asm volatile(
 269                         "       csg     %0,%2,0(%3)\n"
 270                         : "=&d" (prev) : "0" (old), "d" (new), "a" (ptr)
 271                         : "memory", "cc");
 272                 return prev;
 273 #endif /* __s390x__ */
 274         }
 275         __cmpxchg_called_with_bad_pointer();
 276         return old;
 277 }
 278
 279 /*
 280  * Force strict CPU ordering.
 281  * And yes, this is required on UP too when we're talking
 282  * to devices.
 283  *
 284  * This is very similar to the ppc eieio/sync instruction in that is
 285  * does a checkpoint syncronisation & makes sure that
 286  * all memory ops have completed wrt other CPU's ( see 7-15 POP  DJB ).
 287  */
 288
 289 #define eieio() asm volatile("bcr 15,0" : : : "memory")
 290 #define SYNC_OTHER_CORES(x)   eieio()
 291 #define mb()    eieio()
 292 #define rmb()   eieio()
 293 #define wmb()   eieio()
 294 #define read_barrier_depends() do { } while(0)
 295 #define smp_mb()       mb()
 296 #define smp_rmb()      rmb()
 297 #define smp_wmb()      wmb()
 298 #define smp_read_barrier_depends()    read_barrier_depends()
 299 #define smp_mb__before_clear_bit()     smp_mb()
 300 #define smp_mb__after_clear_bit()      smp_mb()
 301
 302
 303 #define set_mb(var, value)      do { var = value; mb(); } while (0)
 304
 305 #ifdef __s390x__
 306
 307 #define __ctl_load(array, low, high) ({                         \
 308         typedef struct { char _[sizeof(array)]; } addrtype;     \
 309         asm volatile(                                           \
 310                 "       lctlg   %1,%2,0(%0)\n"                  \
 311                 : : "a" (&array), "i" (low), "i" (high),        \
 312                     "m" (*(addrtype *)(array)));                \
 313         })
 314
 315 #define __ctl_store(array, low, high) ({                        \
 316         typedef struct { char _[sizeof(array)]; } addrtype;     \
 317         asm volatile(                                           \
 318                 "       stctg   %2,%3,0(%1)\n"                  \
 319                 : "=m" (*(addrtype *)(array))                   \
 320                 : "a" (&array), "i" (low), "i" (high));         \
 321         })
 322
 323 #else /* __s390x__ */
 324
 325 #define __ctl_load(array, low, high) ({                         \
 326         typedef struct { char _[sizeof(array)]; } addrtype;     \
 327         asm volatile(                                           \
 328                 "       lctl    %1,%2,0(%0)\n"                  \
 329                 : : "a" (&array), "i" (low), "i" (high),        \
 330                     "m" (*(addrtype *)(array)));                \
 331 })
 332
 333 #define __ctl_store(array, low, high) ({                        \
 334         typedef struct { char _[sizeof(array)]; } addrtype;     \
 335         asm volatile(                                           \
 336                 "       stctl   %2,%3,0(%1)\n"                  \
 337                 : "=m" (*(addrtype *)(array))                   \
 338                 : "a" (&array), "i" (low), "i" (high));         \
 339         })
 340
 341 #endif /* __s390x__ */
 342
 343 #define __ctl_set_bit(cr, bit) ({       \
 344         unsigned long __dummy;          \
 345         __ctl_store(__dummy, cr, cr);   \
 346         __dummy |= 1UL << (bit);        \
 347         __ctl_load(__dummy, cr, cr);    \
 348 })
 349
 350 #define __ctl_clear_bit(cr, bit) ({     \
 351         unsigned long __dummy;          \
 352         __ctl_store(__dummy, cr, cr);   \
 353         __dummy &= ~(1UL << (bit));     \
 354         __ctl_load(__dummy, cr, cr);    \
 355 })
 356
 357 #include <linux/irqflags.h>
 358
 359 #include <asm-generic/cmpxchg-local.h>
 360
 361 static inline unsigned long __cmpxchg_local(volatile void *ptr,
 362                                       unsigned long old,
 363                                       unsigned long new, int size)
 364 {
 365         switch (size) {
 366         case 1:
 367         case 2:
 368         case 4:
 369 #ifdef __s390x__
 370         case 8:
 371 #endif
 372                 return __cmpxchg(ptr, old, new, size);
 373         default:
 374                 return __cmpxchg_local_generic(ptr, old, new, size);
 375         }
 376
 377         return old;
 378 }
 379
 380 /*
 381  * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make
 382  * them available.
 383  */
 384 #define cmpxchg_local(ptr, o, n)                                        \
 385         ((__typeof__(*(ptr)))__cmpxchg_local((ptr), (unsigned long)(o), \
 386                         (unsigned long)(n), sizeof(*(ptr))))
 387 #ifdef __s390x__
 388 #define cmpxchg64_local(ptr, o, n)                                      \
 389   ({                                                                    \
 390         BUILD_BUG_ON(sizeof(*(ptr)) != 8);                              \
 391         cmpxchg_local((ptr), (o), (n));                                 \
 392   })
 393 #else
 394 #define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))
 395 #endif
 396
 397 /*
 398  * Use to set psw mask except for the first byte which
 399  * won't be changed by this function.
 400  */
 401 static inline void
 402 __set_psw_mask(unsigned long mask)
 403 {
 404         __load_psw_mask(mask | (__raw_local_irq_stosm(0x00) & ~(-1UL >> 8)));
 405 }
 406
 407 #define local_mcck_enable()  __set_psw_mask(psw_kernel_bits)
 408 #define local_mcck_disable() __set_psw_mask(psw_kernel_bits & ~PSW_MASK_MCHECK)
 409
 410 int stfle(unsigned long long *list, int doublewords);
 411
 412 #ifdef CONFIG_SMP
 413
 414 extern void smp_ctl_set_bit(int cr, int bit);
 415 extern void smp_ctl_clear_bit(int cr, int bit);
 416 #define ctl_set_bit(cr, bit) smp_ctl_set_bit(cr, bit)
 417 #define ctl_clear_bit(cr, bit) smp_ctl_clear_bit(cr, bit)
 418
 419 #else
 420
 421 #define ctl_set_bit(cr, bit) __ctl_set_bit(cr, bit)
 422 #define ctl_clear_bit(cr, bit) __ctl_clear_bit(cr, bit)
 423
 424 #endif /* CONFIG_SMP */
 425
 426 static inline unsigned int stfl(void)
 427 {
 428         asm volatile(
 429                 "       .insn   s,0xb2b10000,0(0)\n" /* stfl */
 430                 "0:\n"
 431                 EX_TABLE(0b,0b));
 432         return S390_lowcore.stfl_fac_list;
 433 }
 434
 435 static inline unsigned short stap(void)
 436 {
 437         unsigned short cpu_address;
 438
 439         asm volatile("stap %0" : "=m" (cpu_address));
 440         return cpu_address;
 441 }
 442
 443 extern void (*_machine_restart)(char *command);
 444 extern void (*_machine_halt)(void);
 445 extern void (*_machine_power_off)(void);
 446
 447 #define arch_align_stack(x) (x)
 448
 449 #ifdef CONFIG_TRACE_IRQFLAGS
 450 extern psw_t sysc_restore_trace_psw;
 451 extern psw_t io_restore_trace_psw;
 452 #endif
 453
 454 #endif /* __KERNEL__ */
 455
 456 #endif