arch/arm/include/asm/processor.h

   1 /*
   2  *  arch/arm/include/asm/processor.h
   3  *
   4  *  Copyright (C) 1995-1999 Russell King
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10
  11 #ifndef __ASM_ARM_PROCESSOR_H
  12 #define __ASM_ARM_PROCESSOR_H
  13
  14 /*
  15  * Default implementation of macro that returns current
  16  * instruction pointer ("program counter").
  17  */
  18 #define current_text_addr() ({ __label__ _l; _l: &&_l;})
  19
  20 #ifdef __KERNEL__
  21
  22 #include <asm/hw_breakpoint.h>
  23 #include <asm/ptrace.h>
  24 #include <asm/types.h>
  25
  26 #ifdef __KERNEL__
  27 #define STACK_TOP       ((current->personality & ADDR_LIMIT_32BIT) ? \
  28                          TASK_SIZE : TASK_SIZE_26)
  29 #define STACK_TOP_MAX   TASK_SIZE
  30 #endif
  31
  32 struct debug_info {
  33 #ifdef CONFIG_HAVE_HW_BREAKPOINT
  34         struct perf_event       *hbp[ARM_MAX_HBP_SLOTS];
  35 #endif
  36 };
  37
  38 struct thread_struct {
  39                                                         /* fault info     */
  40         unsigned long           address;
  41         unsigned long           trap_no;
  42         unsigned long           error_code;
  43                                                         /* debugging      */
  44         struct debug_info       debug;
  45 };
  46
  47 #define INIT_THREAD  {  }
  48
  49 #ifdef CONFIG_MMU
  50 #define nommu_start_thread(regs) do { } while (0)
  51 #else
  52 #define nommu_start_thread(regs) regs->ARM_r10 = current->mm->start_data
  53 #endif
  54
  55 #define start_thread(regs,pc,sp)                                        \
  56 ({                                                                      \
  57         unsigned long *stack = (unsigned long *)sp;                     \
  58         set_fs(USER_DS);                                                \
  59         memset(regs->uregs, 0, sizeof(regs->uregs));                    \
  60         if (current->personality & ADDR_LIMIT_32BIT)                    \
  61                 regs->ARM_cpsr = USR_MODE;                              \
  62         else                                                            \
  63                 regs->ARM_cpsr = USR26_MODE;                            \
  64         if (elf_hwcap & HWCAP_THUMB && pc & 1)                          \
  65                 regs->ARM_cpsr |= PSR_T_BIT;                            \
  66         regs->ARM_cpsr |= PSR_ENDSTATE;                                 \
  67         regs->ARM_pc = pc & ~1;         /* pc */                        \
  68         regs->ARM_sp = sp;              /* sp */                        \
  69         regs->ARM_r2 = stack[2];        /* r2 (envp) */                 \
  70         regs->ARM_r1 = stack[1];        /* r1 (argv) */                 \
  71         regs->ARM_r0 = stack[0];        /* r0 (argc) */                 \
  72         nommu_start_thread(regs);                                       \
  73 })
  74
  75 /* Forward declaration, a strange C thing */
  76 struct task_struct;
  77
  78 /* Free all resources held by a thread. */
  79 extern void release_thread(struct task_struct *);
  80
  81 /* Prepare to copy thread state - unlazy all lazy status */
  82 #define prepare_to_copy(tsk)    do { } while (0)
  83
  84 unsigned long get_wchan(struct task_struct *p);
  85
  86 #if __LINUX_ARM_ARCH__ == 6
  87 #define cpu_relax()                     smp_mb()
  88 #else
  89 #define cpu_relax()                     barrier()
  90 #endif
  91
  92 /*
  93  * Create a new kernel thread
  94  */
  95 extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
  96
  97 #define task_pt_regs(p) \
  98         ((struct pt_regs *)(THREAD_START_SP + task_stack_page(p)) - 1)
  99
 100 #define KSTK_EIP(tsk)   task_pt_regs(tsk)->ARM_pc
 101 #define KSTK_ESP(tsk)   task_pt_regs(tsk)->ARM_sp
 102
 103 /*
 104  * Prefetching support - only ARMv5.
 105  */
 106 #if __LINUX_ARM_ARCH__ >= 5
 107
 108 #define ARCH_HAS_PREFETCH
 109 static inline void prefetch(const void *ptr)
 110 {
 111         __asm__ __volatile__(
 112                 "pld\t%a0"
 113                 :
 114                 : "p" (ptr)
 115                 : "cc");
 116 }
 117
 118 #define ARCH_HAS_PREFETCHW
 119 #define prefetchw(ptr)  prefetch(ptr)
 120
 121 #define ARCH_HAS_SPINLOCK_PREFETCH
 122 #define spin_lock_prefetch(x) do { } while (0)
 123
 124 #endif
 125
 126 #endif
 127
 128 #endif /* __ASM_ARM_PROCESSOR_H */