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