include/asm-arm/system.h

   1 #ifndef __ASM_ARM_SYSTEM_H
   2 #define __ASM_ARM_SYSTEM_H
   3
   4 #ifdef __KERNEL__
   5
   6
   7 #define CPU_ARCH_UNKNOWN        0
   8 #define CPU_ARCH_ARMv3          1
   9 #define CPU_ARCH_ARMv4          2
  10 #define CPU_ARCH_ARMv4T         3
  11 #define CPU_ARCH_ARMv5          4
  12 #define CPU_ARCH_ARMv5T         5
  13 #define CPU_ARCH_ARMv5TE        6
  14 #define CPU_ARCH_ARMv5TEJ       7
  15 #define CPU_ARCH_ARMv6          8
  16
  17 /*
  18  * CR1 bits (CP#15 CR1)
  19  */
  20 #define CR_M    (1 << 0)        /* MMU enable                           */
  21 #define CR_A    (1 << 1)        /* Alignment abort enable               */
  22 #define CR_C    (1 << 2)        /* Dcache enable                        */
  23 #define CR_W    (1 << 3)        /* Write buffer enable                  */
  24 #define CR_P    (1 << 4)        /* 32-bit exception handler             */
  25 #define CR_D    (1 << 5)        /* 32-bit data address range            */
  26 #define CR_L    (1 << 6)        /* Implementation defined               */
  27 #define CR_B    (1 << 7)        /* Big endian                           */
  28 #define CR_S    (1 << 8)        /* System MMU protection                */
  29 #define CR_R    (1 << 9)        /* ROM MMU protection                   */
  30 #define CR_F    (1 << 10)       /* Implementation defined               */
  31 #define CR_Z    (1 << 11)       /* Implementation defined               */
  32 #define CR_I    (1 << 12)       /* Icache enable                        */
  33 #define CR_V    (1 << 13)       /* Vectors relocated to 0xffff0000      */
  34 #define CR_RR   (1 << 14)       /* Round Robin cache replacement        */
  35 #define CR_L4   (1 << 15)       /* LDR pc can set T bit                 */
  36 #define CR_DT   (1 << 16)
  37 #define CR_IT   (1 << 18)
  38 #define CR_ST   (1 << 19)
  39 #define CR_FI   (1 << 21)       /* Fast interrupt (lower latency mode)  */
  40 #define CR_U    (1 << 22)       /* Unaligned access operation           */
  41 #define CR_XP   (1 << 23)       /* Extended page tables                 */
  42 #define CR_VE   (1 << 24)       /* Vectored interrupts                  */
  43
  44 #define CPUID_ID        0
  45 #define CPUID_CACHETYPE 1
  46 #define CPUID_TCM       2
  47 #define CPUID_TLBTYPE   3
  48
  49 #define read_cpuid(reg)                                                 \
  50         ({                                                              \
  51                 unsigned int __val;                                     \
  52                 asm("mrc        p15, 0, %0, c0, c0, " __stringify(reg)  \
  53                     : "=r" (__val)                                      \
  54                     :                                                   \
  55                     : "cc");                                            \
  56                 __val;                                                  \
  57         })
  58
  59 /*
  60  * This is used to ensure the compiler did actually allocate the register we
  61  * asked it for some inline assembly sequences.  Apparently we can't trust
  62  * the compiler from one version to another so a bit of paranoia won't hurt.
  63  * This string is meant to be concatenated with the inline asm string and
  64  * will cause compilation to stop on mismatch.
  65  * (for details, see gcc PR 15089)
  66  */
  67 #define __asmeq(x, y)  ".ifnc " x "," y " ; .err ; .endif\n\t"
  68
  69 #ifndef __ASSEMBLY__
  70
  71 #include <linux/linkage.h>
  72
  73 struct thread_info;
  74 struct task_struct;
  75
  76 /* information about the system we're running on */
  77 extern unsigned int system_rev;
  78 extern unsigned int system_serial_low;
  79 extern unsigned int system_serial_high;
  80 extern unsigned int mem_fclk_21285;
  81
  82 struct pt_regs;
  83
  84 void die(const char *msg, struct pt_regs *regs, int err)
  85                 __attribute__((noreturn));
  86
  87 struct siginfo;
  88 void notify_die(const char *str, struct pt_regs *regs, struct siginfo *info,
  89                 unsigned long err, unsigned long trap);
  90
  91 void hook_fault_code(int nr, int (*fn)(unsigned long, unsigned int,
  92                                        struct pt_regs *),
  93                      int sig, const char *name);
  94
  95 #define xchg(ptr,x) \
  96         ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
  97
  98 #define tas(ptr) (xchg((ptr),1))
  99
 100 extern asmlinkage void __backtrace(void);
 101 extern asmlinkage void c_backtrace(unsigned long fp, int pmode);
 102
 103 struct mm_struct;
 104 extern void show_pte(struct mm_struct *mm, unsigned long addr);
 105 extern void __show_regs(struct pt_regs *);
 106
 107 extern int cpu_architecture(void);
 108 extern void cpu_init(void);
 109
 110 void arm_machine_restart(char mode);
 111 extern void (*arm_pm_restart)(char str);
 112
 113 /*
 114  * Intel's XScale3 core supports some v6 features (supersections, L2)
 115  * but advertises itself as v5 as it does not support the v6 ISA.  For
 116  * this reason, we need a way to explicitly test for this type of CPU.
 117  */
 118 #ifndef CONFIG_CPU_XSC3
 119 #define cpu_is_xsc3()   0
 120 #else
 121 static inline int cpu_is_xsc3(void)
 122 {
 123         extern unsigned int processor_id;
 124
 125         if ((processor_id & 0xffffe000) == 0x69056000)
 126                 return 1;
 127
 128         return 0;
 129 }
 130 #endif
 131
 132 #if !defined(CONFIG_CPU_XSCALE) && !defined(CONFIG_CPU_XSC3)
 133 #define cpu_is_xscale() 0
 134 #else
 135 #define cpu_is_xscale() 1
 136 #endif
 137
 138 #define set_cr(x)                                       \
 139         __asm__ __volatile__(                           \
 140         "mcr    p15, 0, %0, c1, c0, 0   @ set CR"       \
 141         : : "r" (x) : "cc")
 142
 143 #define get_cr()                                        \
 144         ({                                              \
 145         unsigned int __val;                             \
 146         __asm__ __volatile__(                           \
 147         "mrc    p15, 0, %0, c1, c0, 0   @ get CR"       \
 148         : "=r" (__val) : : "cc");                       \
 149         __val;                                          \
 150         })
 151
 152 extern unsigned long cr_no_alignment;   /* defined in entry-armv.S */
 153 extern unsigned long cr_alignment;      /* defined in entry-armv.S */
 154
 155 #define UDBG_UNDEFINED  (1 << 0)
 156 #define UDBG_SYSCALL    (1 << 1)
 157 #define UDBG_BADABORT   (1 << 2)
 158 #define UDBG_SEGV       (1 << 3)
 159 #define UDBG_BUS        (1 << 4)
 160
 161 extern unsigned int user_debug;
 162
 163 #if __LINUX_ARM_ARCH__ >= 4
 164 #define vectors_high()  (cr_alignment & CR_V)
 165 #else
 166 #define vectors_high()  (0)
 167 #endif
 168
 169 #if __LINUX_ARM_ARCH__ >= 6
 170 #define mb() __asm__ __volatile__ ("mcr p15, 0, %0, c7, c10, 5" \
 171                                    : : "r" (0) : "memory")
 172 #else
 173 #define mb() __asm__ __volatile__ ("" : : : "memory")
 174 #endif
 175 #define rmb() mb()
 176 #define wmb() mb()
 177 #define read_barrier_depends() do { } while(0)
 178 #define set_mb(var, value)  do { var = value; mb(); } while (0)
 179 #define set_wmb(var, value) do { var = value; wmb(); } while (0)
 180 #define nop() __asm__ __volatile__("mov\tr0,r0\t@ nop\n\t");
 181
 182 /*
 183  * switch_mm() may do a full cache flush over the context switch,
 184  * so enable interrupts over the context switch to avoid high
 185  * latency.
 186  */
 187 #define __ARCH_WANT_INTERRUPTS_ON_CTXSW
 188
 189 /*
 190  * switch_to(prev, next) should switch from task `prev' to `next'
 191  * `prev' will never be the same as `next'.  schedule() itself
 192  * contains the memory barrier to tell GCC not to cache `current'.
 193  */
 194 extern struct task_struct *__switch_to(struct task_struct *, struct thread_info *, struct thread_info *);
 195
 196 #define switch_to(prev,next,last)                                       \
 197 do {                                                                    \
 198         last = __switch_to(prev,task_thread_info(prev), task_thread_info(next));        \
 199 } while (0)
 200
 201 /*
 202  * On SMP systems, when the scheduler does migration-cost autodetection,
 203  * it needs a way to flush as much of the CPU's caches as possible.
 204  *
 205  * TODO: fill this in!
 206  */
 207 static inline void sched_cacheflush(void)
 208 {
 209 }
 210
 211 /*
 212  * CPU interrupt mask handling.
 213  */
 214 #if __LINUX_ARM_ARCH__ >= 6
 215
 216 #define local_irq_save(x)                                       \
 217         ({                                                      \
 218         __asm__ __volatile__(                                   \
 219         "mrs    %0, cpsr                @ local_irq_save\n"     \
 220         "cpsid  i"                                              \
 221         : "=r" (x) : : "memory", "cc");                         \
 222         })
 223
 224 #define local_irq_enable()  __asm__("cpsie i    @ __sti" : : : "memory", "cc")
 225 #define local_irq_disable() __asm__("cpsid i    @ __cli" : : : "memory", "cc")
 226 #define local_fiq_enable()  __asm__("cpsie f    @ __stf" : : : "memory", "cc")
 227 #define local_fiq_disable() __asm__("cpsid f    @ __clf" : : : "memory", "cc")
 228
 229 #else
 230
 231 /*
 232  * Save the current interrupt enable state & disable IRQs
 233  */
 234 #define local_irq_save(x)                                       \
 235         ({                                                      \
 236                 unsigned long temp;                             \
 237                 (void) (&temp == &x);                           \
 238         __asm__ __volatile__(                                   \
 239         "mrs    %0, cpsr                @ local_irq_save\n"     \
 240 "       orr     %1, %0, #128\n"                                 \
 241 "       msr     cpsr_c, %1"                                     \
 242         : "=r" (x), "=r" (temp)                                 \
 243         :                                                       \
 244         : "memory", "cc");                                      \
 245         })
 246
 247 /*
 248  * Enable IRQs
 249  */
 250 #define local_irq_enable()                                      \
 251         ({                                                      \
 252                 unsigned long temp;                             \
 253         __asm__ __volatile__(                                   \
 254         "mrs    %0, cpsr                @ local_irq_enable\n"   \
 255 "       bic     %0, %0, #128\n"                                 \
 256 "       msr     cpsr_c, %0"                                     \
 257         : "=r" (temp)                                           \
 258         :                                                       \
 259         : "memory", "cc");                                      \
 260         })
 261
 262 /*
 263  * Disable IRQs
 264  */
 265 #define local_irq_disable()                                     \
 266         ({                                                      \
 267                 unsigned long temp;                             \
 268         __asm__ __volatile__(                                   \
 269         "mrs    %0, cpsr                @ local_irq_disable\n"  \
 270 "       orr     %0, %0, #128\n"                                 \
 271 "       msr     cpsr_c, %0"                                     \
 272         : "=r" (temp)                                           \
 273         :                                                       \
 274         : "memory", "cc");                                      \
 275         })
 276
 277 /*
 278  * Enable FIQs
 279  */
 280 #define local_fiq_enable()                                      \
 281         ({                                                      \
 282                 unsigned long temp;                             \
 283         __asm__ __volatile__(                                   \
 284         "mrs    %0, cpsr                @ stf\n"                \
 285 "       bic     %0, %0, #64\n"                                  \
 286 "       msr     cpsr_c, %0"                                     \
 287         : "=r" (temp)                                           \
 288         :                                                       \
 289         : "memory", "cc");                                      \
 290         })
 291
 292 /*
 293  * Disable FIQs
 294  */
 295 #define local_fiq_disable()                                     \
 296         ({                                                      \
 297                 unsigned long temp;                             \
 298         __asm__ __volatile__(                                   \
 299         "mrs    %0, cpsr                @ clf\n"                \
 300 "       orr     %0, %0, #64\n"                                  \
 301 "       msr     cpsr_c, %0"                                     \
 302         : "=r" (temp)                                           \
 303         :                                                       \
 304         : "memory", "cc");                                      \
 305         })
 306
 307 #endif
 308
 309 /*
 310  * Save the current interrupt enable state.
 311  */
 312 #define local_save_flags(x)                                     \
 313         ({                                                      \
 314         __asm__ __volatile__(                                   \
 315         "mrs    %0, cpsr                @ local_save_flags"     \
 316         : "=r" (x) : : "memory", "cc");                         \
 317         })
 318
 319 /*
 320  * restore saved IRQ & FIQ state
 321  */
 322 #define local_irq_restore(x)                                    \
 323         __asm__ __volatile__(                                   \
 324         "msr    cpsr_c, %0              @ local_irq_restore\n"  \
 325         :                                                       \
 326         : "r" (x)                                               \
 327         : "memory", "cc")
 328
 329 #define irqs_disabled()                 \
 330 ({                                      \
 331         unsigned long flags;            \
 332         local_save_flags(flags);        \
 333         (int)(flags & PSR_I_BIT);       \
 334 })
 335
 336 #ifdef CONFIG_SMP
 337
 338 #define smp_mb()                mb()
 339 #define smp_rmb()               rmb()
 340 #define smp_wmb()               wmb()
 341 #define smp_read_barrier_depends()              read_barrier_depends()
 342
 343 #else
 344
 345 #define smp_mb()                barrier()
 346 #define smp_rmb()               barrier()
 347 #define smp_wmb()               barrier()
 348 #define smp_read_barrier_depends()              do { } while(0)
 349
 350 #endif /* CONFIG_SMP */
 351
 352 #if defined(CONFIG_CPU_SA1100) || defined(CONFIG_CPU_SA110)
 353 /*
 354  * On the StrongARM, "swp" is terminally broken since it bypasses the
 355  * cache totally.  This means that the cache becomes inconsistent, and,
 356  * since we use normal loads/stores as well, this is really bad.
 357  * Typically, this causes oopsen in filp_close, but could have other,
 358  * more disasterous effects.  There are two work-arounds:
 359  *  1. Disable interrupts and emulate the atomic swap
 360  *  2. Clean the cache, perform atomic swap, flush the cache
 361  *
 362  * We choose (1) since its the "easiest" to achieve here and is not
 363  * dependent on the processor type.
 364  *
 365  * NOTE that this solution won't work on an SMP system, so explcitly
 366  * forbid it here.
 367  */
 368 #define swp_is_buggy
 369 #endif
 370
 371 static inline unsigned long __xchg(unsigned long x, volatile void *ptr, int size)
 372 {
 373         extern void __bad_xchg(volatile void *, int);
 374         unsigned long ret;
 375 #ifdef swp_is_buggy
 376         unsigned long flags;
 377 #endif
 378 #if __LINUX_ARM_ARCH__ >= 6
 379         unsigned int tmp;
 380 #endif
 381
 382         switch (size) {
 383 #if __LINUX_ARM_ARCH__ >= 6
 384         case 1:
 385                 asm volatile("@ __xchg1\n"
 386                 "1:     ldrexb  %0, [%3]\n"
 387                 "       strexb  %1, %2, [%3]\n"
 388                 "       teq     %1, #0\n"
 389                 "       bne     1b"
 390                         : "=&r" (ret), "=&r" (tmp)
 391                         : "r" (x), "r" (ptr)
 392                         : "memory", "cc");
 393                 break;
 394         case 4:
 395                 asm volatile("@ __xchg4\n"
 396                 "1:     ldrex   %0, [%3]\n"
 397                 "       strex   %1, %2, [%3]\n"
 398                 "       teq     %1, #0\n"
 399                 "       bne     1b"
 400                         : "=&r" (ret), "=&r" (tmp)
 401                         : "r" (x), "r" (ptr)
 402                         : "memory", "cc");
 403                 break;
 404 #elif defined(swp_is_buggy)
 405 #ifdef CONFIG_SMP
 406 #error SMP is not supported on this platform
 407 #endif
 408         case 1:
 409                 local_irq_save(flags);
 410                 ret = *(volatile unsigned char *)ptr;
 411                 *(volatile unsigned char *)ptr = x;
 412                 local_irq_restore(flags);
 413                 break;
 414
 415         case 4:
 416                 local_irq_save(flags);
 417                 ret = *(volatile unsigned long *)ptr;
 418                 *(volatile unsigned long *)ptr = x;
 419                 local_irq_restore(flags);
 420                 break;
 421 #else
 422         case 1:
 423                 asm volatile("@ __xchg1\n"
 424                 "       swpb    %0, %1, [%2]"
 425                         : "=&r" (ret)
 426                         : "r" (x), "r" (ptr)
 427                         : "memory", "cc");
 428                 break;
 429         case 4:
 430                 asm volatile("@ __xchg4\n"
 431                 "       swp     %0, %1, [%2]"
 432                         : "=&r" (ret)
 433                         : "r" (x), "r" (ptr)
 434                         : "memory", "cc");
 435                 break;
 436 #endif
 437         default:
 438                 __bad_xchg(ptr, size), ret = 0;
 439                 break;
 440         }
 441
 442         return ret;
 443 }
 444
 445 extern void disable_hlt(void);
 446 extern void enable_hlt(void);
 447
 448 #endif /* __ASSEMBLY__ */
 449
 450 #define arch_align_stack(x) (x)
 451
 452 #endif /* __KERNEL__ */
 453
 454 #endif