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/hw_breakpoint.h>
  23#include <asm/ptrace.h>
  24#include <asm/types.h>
  25#include <asm/unified.h>
  26
  27#ifdef __KERNEL__
  28#define STACK_TOP       ((current->personality & ADDR_LIMIT_32BIT) ? \
  29                         TASK_SIZE : TASK_SIZE_26)
  30#define STACK_TOP_MAX   TASK_SIZE
  31#endif
  32
  33struct debug_info {
  34#ifdef CONFIG_HAVE_HW_BREAKPOINT
  35        struct perf_event       *hbp[ARM_MAX_HBP_SLOTS];
  36#endif
  37};
  38
  39struct thread_struct {
  40                                                        /* fault info     */
  41        unsigned long           address;
  42        unsigned long           trap_no;
  43        unsigned long           error_code;
  44                                                        /* debugging      */
  45        struct debug_info       debug;
  46};
  47
  48#define INIT_THREAD  {  }
  49
  50#ifdef CONFIG_MMU
  51#define nommu_start_thread(regs) do { } while (0)
  52#else
  53#define nommu_start_thread(regs) regs->ARM_r10 = current->mm->start_data
  54#endif
  55
  56#define start_thread(regs,pc,sp)                                        \
  57({                                                                      \
  58        memset(regs->uregs, 0, sizeof(regs->uregs));                    \
  59        if (current->personality & ADDR_LIMIT_32BIT)                    \
  60                regs->ARM_cpsr = USR_MODE;                              \
  61        else                                                            \
  62                regs->ARM_cpsr = USR26_MODE;                            \
  63        if (elf_hwcap & HWCAP_THUMB && pc & 1)                          \
  64                regs->ARM_cpsr |= PSR_T_BIT;                            \
  65        regs->ARM_cpsr |= PSR_ENDSTATE;                                 \
  66        regs->ARM_pc = pc & ~1;         /* pc */                        \
  67        regs->ARM_sp = sp;              /* sp */                        \
  68        nommu_start_thread(regs);                                       \
  69})
  70
  71/* Forward declaration, a strange C thing */
  72struct task_struct;
  73
  74/* Free all resources held by a thread. */
  75extern void release_thread(struct task_struct *);
  76
  77unsigned long get_wchan(struct task_struct *p);
  78
  79#if __LINUX_ARM_ARCH__ == 6 || defined(CONFIG_ARM_ERRATA_754327)
  80#define cpu_relax()                     smp_mb()
  81#else
  82#define cpu_relax()                     barrier()
  83#endif
  84
  85#define cpu_relax_lowlatency()                cpu_relax()
  86
  87#define task_pt_regs(p) \
  88        ((struct pt_regs *)(THREAD_START_SP + task_stack_page(p)) - 1)
  89
  90#define KSTK_EIP(tsk)   task_pt_regs(tsk)->ARM_pc
  91#define KSTK_ESP(tsk)   task_pt_regs(tsk)->ARM_sp
  92
  93#ifdef CONFIG_SMP
  94#define __ALT_SMP_ASM(smp, up)                                          \
  95        "9998:  " smp "\n"                                              \
  96        "       .pushsection \".alt.smp.init\", \"a\"\n"                \
  97        "       .long   9998b\n"                                        \
  98        "       " up "\n"                                               \
  99        "       .popsection\n"
 100#else
 101#define __ALT_SMP_ASM(smp, up)  up
 102#endif
 103
 104/*
 105 * Prefetching support - only ARMv5.
 106 */
 107#if __LINUX_ARM_ARCH__ >= 5
 108
 109#define ARCH_HAS_PREFETCH
 110static inline void prefetch(const void *ptr)
 111{
 112        __asm__ __volatile__(
 113                "pld\t%a0"
 114                :: "p" (ptr));
 115}
 116
 117#if __LINUX_ARM_ARCH__ >= 7 && defined(CONFIG_SMP)
 118#define ARCH_HAS_PREFETCHW
 119static inline void prefetchw(const void *ptr)
 120{
 121        __asm__ __volatile__(
 122                ".arch_extension        mp\n"
 123                __ALT_SMP_ASM(
 124                        WASM(pldw)              "\t%a0",
 125                        WASM(pld)               "\t%a0"
 126                )
 127                :: "p" (ptr));
 128}
 129#endif
 130#endif
 131
 132#define HAVE_ARCH_PICK_MMAP_LAYOUT
 133
 134#endif
 135
 136#endif /* __ASM_ARM_PROCESSOR_H */
 137