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