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 void die_if_kernel(const char *str, struct pt_regs *regs, int err);
  89
  90 void hook_fault_code(int nr, int (*fn)(unsigned long, unsigned int,
  91                                        struct pt_regs *),
  92                      int sig, const char *name);
  93
  94 #include <asm/proc-fns.h>
  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 extern void show_pte(struct mm_struct *mm, unsigned long addr);
 104 extern void __show_regs(struct pt_regs *);
 105
 106 extern int cpu_architecture(void);
 107 extern void cpu_init(void);
 108
 109 #define set_cr(x)                                       \
 110         __asm__ __volatile__(                           \
 111         "mcr    p15, 0, %0, c1, c0, 0   @ set CR"       \
 112         : : "r" (x) : "cc")
 113
 114 #define get_cr()                                        \
 115         ({                                              \
 116         unsigned int __val;                             \
 117         __asm__ __volatile__(                           \
 118         "mrc    p15, 0, %0, c1, c0, 0   @ get CR"       \
 119         : "=r" (__val) : : "cc");                       \
 120         __val;                                          \
 121         })
 122
 123 extern unsigned long cr_no_alignment;   /* defined in entry-armv.S */
 124 extern unsigned long cr_alignment;      /* defined in entry-armv.S */
 125
 126 #define UDBG_UNDEFINED  (1 << 0)
 127 #define UDBG_SYSCALL    (1 << 1)
 128 #define UDBG_BADABORT   (1 << 2)
 129 #define UDBG_SEGV       (1 << 3)
 130 #define UDBG_BUS        (1 << 4)
 131
 132 extern unsigned int user_debug;
 133
 134 #if __LINUX_ARM_ARCH__ >= 4
 135 #define vectors_high()  (cr_alignment & CR_V)
 136 #else
 137 #define vectors_high()  (0)
 138 #endif
 139
 140 #define mb() __asm__ __volatile__ ("" : : : "memory")
 141 #define rmb() mb()
 142 #define wmb() mb()
 143 #define read_barrier_depends() do { } while(0)
 144 #define set_mb(var, value)  do { var = value; mb(); } while (0)
 145 #define set_wmb(var, value) do { var = value; wmb(); } while (0)
 146 #define nop() __asm__ __volatile__("mov\tr0,r0\t@ nop\n\t");
 147
 148 #ifdef CONFIG_SMP
 149 /*
 150  * Define our own context switch locking.  This allows us to enable
 151  * interrupts over the context switch, otherwise we end up with high
 152  * interrupt latency.  The real problem area is switch_mm() which may
 153  * do a full cache flush.
 154  */
 155 #define prepare_arch_switch(rq,next)                                    \
 156 do {                                                                    \
 157         spin_lock(&(next)->switch_lock);                                \
 158         spin_unlock_irq(&(rq)->lock);                                   \
 159 } while (0)
 160
 161 #define finish_arch_switch(rq,prev)                                     \
 162         spin_unlock(&(prev)->switch_lock)
 163
 164 #define task_running(rq,p)                                              \
 165         ((rq)->curr == (p) || spin_is_locked(&(p)->switch_lock))
 166 #else
 167 /*
 168  * Our UP-case is more simple, but we assume knowledge of how
 169  * spin_unlock_irq() and friends are implemented.  This avoids
 170  * us needlessly decrementing and incrementing the preempt count.
 171  */
 172 #define prepare_arch_switch(rq,next)    local_irq_enable()
 173 #define finish_arch_switch(rq,prev)     spin_unlock(&(rq)->lock)
 174 #define task_running(rq,p)              ((rq)->curr == (p))
 175 #endif
 176
 177 /*
 178  * switch_to(prev, next) should switch from task `prev' to `next'
 179  * `prev' will never be the same as `next'.  schedule() itself
 180  * contains the memory barrier to tell GCC not to cache `current'.
 181  */
 182 extern struct task_struct *__switch_to(struct task_struct *, struct thread_info *, struct thread_info *);
 183
 184 #define switch_to(prev,next,last)                                       \
 185 do {                                                                    \
 186         last = __switch_to(prev,prev->thread_info,next->thread_info);   \
 187 } while (0)
 188
 189 /*
 190  * CPU interrupt mask handling.
 191  */
 192 #if __LINUX_ARM_ARCH__ >= 6
 193
 194 #define local_irq_save(x)                                       \
 195         ({                                                      \
 196         __asm__ __volatile__(                                   \
 197         "mrs    %0, cpsr                @ local_irq_save\n"     \
 198         "cpsid  i"                                              \
 199         : "=r" (x) : : "memory", "cc");                         \
 200         })
 201
 202 #define local_irq_enable()  __asm__("cpsie i    @ __sti" : : : "memory", "cc")
 203 #define local_irq_disable() __asm__("cpsid i    @ __cli" : : : "memory", "cc")
 204 #define local_fiq_enable()  __asm__("cpsie f    @ __stf" : : : "memory", "cc")
 205 #define local_fiq_disable() __asm__("cpsid f    @ __clf" : : : "memory", "cc")
 206
 207 #else
 208
 209 /*
 210  * Save the current interrupt enable state & disable IRQs
 211  */
 212 #define local_irq_save(x)                                       \
 213         ({                                                      \
 214                 unsigned long temp;                             \
 215                 (void) (&temp == &x);                           \
 216         __asm__ __volatile__(                                   \
 217         "mrs    %0, cpsr                @ local_irq_save\n"     \
 218 "       orr     %1, %0, #128\n"                                 \
 219 "       msr     cpsr_c, %1"                                     \
 220         : "=r" (x), "=r" (temp)                                 \
 221         :                                                       \
 222         : "memory", "cc");                                      \
 223         })
 224
 225 /*
 226  * Enable IRQs
 227  */
 228 #define local_irq_enable()                                      \
 229         ({                                                      \
 230                 unsigned long temp;                             \
 231         __asm__ __volatile__(                                   \
 232         "mrs    %0, cpsr                @ local_irq_enable\n"   \
 233 "       bic     %0, %0, #128\n"                                 \
 234 "       msr     cpsr_c, %0"                                     \
 235         : "=r" (temp)                                           \
 236         :                                                       \
 237         : "memory", "cc");                                      \
 238         })
 239
 240 /*
 241  * Disable IRQs
 242  */
 243 #define local_irq_disable()                                     \
 244         ({                                                      \
 245                 unsigned long temp;                             \
 246         __asm__ __volatile__(                                   \
 247         "mrs    %0, cpsr                @ local_irq_disable\n"  \
 248 "       orr     %0, %0, #128\n"                                 \
 249 "       msr     cpsr_c, %0"                                     \
 250         : "=r" (temp)                                           \
 251         :                                                       \
 252         : "memory", "cc");                                      \
 253         })
 254
 255 /*
 256  * Enable FIQs
 257  */
 258 #define local_fiq_enable()                                      \
 259         ({                                                      \
 260                 unsigned long temp;                             \
 261         __asm__ __volatile__(                                   \
 262         "mrs    %0, cpsr                @ stf\n"                \
 263 "       bic     %0, %0, #64\n"                                  \
 264 "       msr     cpsr_c, %0"                                     \
 265         : "=r" (temp)                                           \
 266         :                                                       \
 267         : "memory", "cc");                                      \
 268         })
 269
 270 /*
 271  * Disable FIQs
 272  */
 273 #define local_fiq_disable()                                     \
 274         ({                                                      \
 275                 unsigned long temp;                             \
 276         __asm__ __volatile__(                                   \
 277         "mrs    %0, cpsr                @ clf\n"                \
 278 "       orr     %0, %0, #64\n"                                  \
 279 "       msr     cpsr_c, %0"                                     \
 280         : "=r" (temp)                                           \
 281         :                                                       \
 282         : "memory", "cc");                                      \
 283         })
 284
 285 #endif
 286
 287 /*
 288  * Save the current interrupt enable state.
 289  */
 290 #define local_save_flags(x)                                     \
 291         ({                                                      \
 292         __asm__ __volatile__(                                   \
 293         "mrs    %0, cpsr                @ local_save_flags"     \
 294         : "=r" (x) : : "memory", "cc");                         \
 295         })
 296
 297 /*
 298  * restore saved IRQ & FIQ state
 299  */
 300 #define local_irq_restore(x)                                    \
 301         __asm__ __volatile__(                                   \
 302         "msr    cpsr_c, %0              @ local_irq_restore\n"  \
 303         :                                                       \
 304         : "r" (x)                                               \
 305         : "memory", "cc")
 306
 307 #define irqs_disabled()                 \
 308 ({                                      \
 309         unsigned long flags;            \
 310         local_save_flags(flags);        \
 311         (int)(flags & PSR_I_BIT);       \
 312 })
 313
 314 #ifdef CONFIG_SMP
 315 #error SMP not supported
 316
 317 #define smp_mb()                mb()
 318 #define smp_rmb()               rmb()
 319 #define smp_wmb()               wmb()
 320 #define smp_read_barrier_depends()              read_barrier_depends()
 321
 322 #else
 323
 324 #define smp_mb()                barrier()
 325 #define smp_rmb()               barrier()
 326 #define smp_wmb()               barrier()
 327 #define smp_read_barrier_depends()              do { } while(0)
 328
 329 #if defined(CONFIG_CPU_SA1100) || defined(CONFIG_CPU_SA110)
 330 /*
 331  * On the StrongARM, "swp" is terminally broken since it bypasses the
 332  * cache totally.  This means that the cache becomes inconsistent, and,
 333  * since we use normal loads/stores as well, this is really bad.
 334  * Typically, this causes oopsen in filp_close, but could have other,
 335  * more disasterous effects.  There are two work-arounds:
 336  *  1. Disable interrupts and emulate the atomic swap
 337  *  2. Clean the cache, perform atomic swap, flush the cache
 338  *
 339  * We choose (1) since its the "easiest" to achieve here and is not
 340  * dependent on the processor type.
 341  */
 342 #define swp_is_buggy
 343 #endif
 344
 345 static inline unsigned long __xchg(unsigned long x, volatile void *ptr, int size)
 346 {
 347         extern void __bad_xchg(volatile void *, int);
 348         unsigned long ret;
 349 #ifdef swp_is_buggy
 350         unsigned long flags;
 351 #endif
 352
 353         switch (size) {
 354 #ifdef swp_is_buggy
 355                 case 1:
 356                         local_irq_save(flags);
 357                         ret = *(volatile unsigned char *)ptr;
 358                         *(volatile unsigned char *)ptr = x;
 359                         local_irq_restore(flags);
 360                         break;
 361
 362                 case 4:
 363                         local_irq_save(flags);
 364                         ret = *(volatile unsigned long *)ptr;
 365                         *(volatile unsigned long *)ptr = x;
 366                         local_irq_restore(flags);
 367                         break;
 368 #else
 369                 case 1: __asm__ __volatile__ ("swpb %0, %1, [%2]"
 370                                         : "=&r" (ret)
 371                                         : "r" (x), "r" (ptr)
 372                                         : "memory", "cc");
 373                         break;
 374                 case 4: __asm__ __volatile__ ("swp %0, %1, [%2]"
 375                                         : "=&r" (ret)
 376                                         : "r" (x), "r" (ptr)
 377                                         : "memory", "cc");
 378                         break;
 379 #endif
 380                 default: __bad_xchg(ptr, size), ret = 0;
 381         }
 382
 383         return ret;
 384 }
 385
 386 #endif /* CONFIG_SMP */
 387
 388 #endif /* __ASSEMBLY__ */
 389
 390 #define arch_align_stack(x) (x)
 391
 392 #endif /* __KERNEL__ */
 393
 394 #endif