LXR linux/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/ptrace.h>
  23#include <asm/types.h>
  24
  25#ifdef __KERNEL__
  26#define STACK_TOP       ((current->personality & ADDR_LIMIT_32BIT) ? \
  27                         TASK_SIZE : TASK_SIZE_26)
  28#define STACK_TOP_MAX   TASK_SIZE
  29#endif
  30
  31union debug_insn {
  32        u32     arm;
  33        u16     thumb;
  34};
  35
  36struct debug_entry {
  37        u32                     address;
  38        union debug_insn        insn;
  39};
  40
  41struct debug_info {
  42        int                     nsaved;
  43        struct debug_entry      bp[2];
  44};
  45
  46struct thread_struct {
  47                                                        /* fault info     */
  48        unsigned long           address;
  49        unsigned long           trap_no;
  50        unsigned long           error_code;
  51                                                        /* debugging      */
  52        struct debug_info       debug;
  53};
  54
  55#define INIT_THREAD  {  }
  56
  57#ifdef CONFIG_MMU
  58#define nommu_start_thread(regs) do { } while (0)
  59#else
  60#define nommu_start_thread(regs) regs->ARM_r10 = current->mm->start_data
  61#endif
  62
  63#define start_thread(regs,pc,sp)                                        \
  64({                                                                      \
  65        unsigned long *stack = (unsigned long *)sp;                     \
  66        set_fs(USER_DS);                                                \
  67        memset(regs->uregs, 0, sizeof(regs->uregs));                    \
  68        if (current->personality & ADDR_LIMIT_32BIT)                    \
  69                regs->ARM_cpsr = USR_MODE;                              \
  70        else                                                            \
  71                regs->ARM_cpsr = USR26_MODE;                            \
  72        if (elf_hwcap & HWCAP_THUMB && pc & 1)                          \
  73                regs->ARM_cpsr |= PSR_T_BIT;                            \
  74        regs->ARM_cpsr |= PSR_ENDSTATE;                                 \
  75        regs->ARM_pc = pc & ~1;         /* pc */                        \
  76        regs->ARM_sp = sp;              /* sp */                        \
  77        regs->ARM_r2 = stack[2];        /* r2 (envp) */                 \
  78        regs->ARM_r1 = stack[1];        /* r1 (argv) */                 \
  79        regs->ARM_r0 = stack[0];        /* r0 (argc) */                 \
  80        nommu_start_thread(regs);                                       \
  81})
  82
  83/* Forward declaration, a strange C thing */
  84struct task_struct;
  85
  86/* Free all resources held by a thread. */
  87extern void release_thread(struct task_struct *);
  88
  89/* Prepare to copy thread state - unlazy all lazy status */
  90#define prepare_to_copy(tsk)    do { } while (0)
  91
  92unsigned long get_wchan(struct task_struct *p);
  93
  94#define cpu_relax()                     barrier()
  95
  96/*
  97 * Create a new kernel thread
  98 */
  99extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
 100
 101#define task_pt_regs(p) \
 102        ((struct pt_regs *)(THREAD_START_SP + task_stack_page(p)) - 1)
 103
 104#define KSTK_EIP(tsk)   task_pt_regs(tsk)->ARM_pc
 105#define KSTK_ESP(tsk)   task_pt_regs(tsk)->ARM_sp
 106
 107/*
 108 * Prefetching support - only ARMv5.
 109 */
 110#if __LINUX_ARM_ARCH__ >= 5
 111
 112#define ARCH_HAS_PREFETCH
 113static inline void prefetch(const void *ptr)
 114{
 115        __asm__ __volatile__(
 116                "pld\t%a0"
 117                :
 118                : "p" (ptr)
 119                : "cc");
 120}
 121
 122#define ARCH_HAS_PREFETCHW
 123#define prefetchw(ptr)  prefetch(ptr)
 124
 125#define ARCH_HAS_SPINLOCK_PREFETCH
 126#define spin_lock_prefetch(x) do { } while (0)
 127
 128#endif
 129
 130#endif
 131
 132#endif /* __ASM_ARM_PROCESSOR_H */
 133