include/asm-arm/system.h

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