LXR linux/arch/arm/include/asm/processor.h

   1/* SPDX-License-Identifier: GPL-2.0-only */
   2/*
   3 *  arch/arm/include/asm/processor.h
   4 *
   5 *  Copyright (C) 1995-1999 Russell King
   6 */
   7
   8#ifndef __ASM_ARM_PROCESSOR_H
   9#define __ASM_ARM_PROCESSOR_H
  10
  11#ifdef __KERNEL__
  12
  13#include <asm/hw_breakpoint.h>
  14#include <asm/ptrace.h>
  15#include <asm/types.h>
  16#include <asm/unified.h>
  17#include <asm/vdso/processor.h>
  18
  19#ifdef __KERNEL__
  20#define STACK_TOP       ((current->personality & ADDR_LIMIT_32BIT) ? \
  21                         TASK_SIZE : TASK_SIZE_26)
  22#define STACK_TOP_MAX   TASK_SIZE
  23#endif
  24
  25struct debug_info {
  26#ifdef CONFIG_HAVE_HW_BREAKPOINT
  27        struct perf_event       *hbp[ARM_MAX_HBP_SLOTS];
  28#endif
  29};
  30
  31struct thread_struct {
  32                                                        /* fault info     */
  33        unsigned long           address;
  34        unsigned long           trap_no;
  35        unsigned long           error_code;
  36                                                        /* debugging      */
  37        struct debug_info       debug;
  38};
  39
  40/*
  41 * Everything usercopied to/from thread_struct is statically-sized, so
  42 * no hardened usercopy whitelist is needed.
  43 */
  44static inline void arch_thread_struct_whitelist(unsigned long *offset,
  45                                                unsigned long *size)
  46{
  47        *offset = *size = 0;
  48}
  49
  50#define INIT_THREAD  {  }
  51
  52#define start_thread(regs,pc,sp)                                        \
  53({                                                                      \
  54        unsigned long r7, r8, r9;                                       \
  55                                                                        \
  56        if (IS_ENABLED(CONFIG_BINFMT_ELF_FDPIC)) {                      \
  57                r7 = regs->ARM_r7;                                      \
  58                r8 = regs->ARM_r8;                                      \
  59                r9 = regs->ARM_r9;                                      \
  60        }                                                               \
  61        memset(regs->uregs, 0, sizeof(regs->uregs));                    \
  62        if (IS_ENABLED(CONFIG_BINFMT_ELF_FDPIC) &&                      \
  63            current->personality & FDPIC_FUNCPTRS) {                    \
  64                regs->ARM_r7 = r7;                                      \
  65                regs->ARM_r8 = r8;                                      \
  66                regs->ARM_r9 = r9;                                      \
  67                regs->ARM_r10 = current->mm->start_data;                \
  68        } else if (!IS_ENABLED(CONFIG_MMU))                             \
  69                regs->ARM_r10 = current->mm->start_data;                \
  70        if (current->personality & ADDR_LIMIT_32BIT)                    \
  71                regs->ARM_cpsr = USR_MODE;                              \
  72        else                                                            \
  73                regs->ARM_cpsr = USR26_MODE;                            \
  74        if (elf_hwcap & HWCAP_THUMB && pc & 1)                          \
  75                regs->ARM_cpsr |= PSR_T_BIT;                            \
  76        regs->ARM_cpsr |= PSR_ENDSTATE;                                 \
  77        regs->ARM_pc = pc & ~1;         /* pc */                        \
  78        regs->ARM_sp = sp;              /* sp */                        \
  79})
  80
  81/* Forward declaration, a strange C thing */
  82struct task_struct;
  83
  84/* Free all resources held by a thread. */
  85extern void release_thread(struct task_struct *);
  86
  87unsigned long get_wchan(struct task_struct *p);
  88
  89#define task_pt_regs(p) \
  90        ((struct pt_regs *)(THREAD_START_SP + task_stack_page(p)) - 1)
  91
  92#define KSTK_EIP(tsk)   task_pt_regs(tsk)->ARM_pc
  93#define KSTK_ESP(tsk)   task_pt_regs(tsk)->ARM_sp
  94
  95#ifdef CONFIG_SMP
  96#define __ALT_SMP_ASM(smp, up)                                          \
  97        "9998:  " smp "\n"                                              \
  98        "       .pushsection \".alt.smp.init\", \"a\"\n"                \
  99        "       .long   9998b - .\n"                                    \
 100        "       " up "\n"                                               \
 101        "       .popsection\n"
 102#else
 103#define __ALT_SMP_ASM(smp, up)  up
 104#endif
 105
 106/*
 107 * Prefetching support - only ARMv5.
 108 */
 109#if __LINUX_ARM_ARCH__ >= 5
 110
 111#define ARCH_HAS_PREFETCH
 112static inline void prefetch(const void *ptr)
 113{
 114        __asm__ __volatile__(
 115                "pld\t%a0"
 116                :: "p" (ptr));
 117}
 118
 119#if __LINUX_ARM_ARCH__ >= 7 && defined(CONFIG_SMP)
 120#define ARCH_HAS_PREFETCHW
 121static inline void prefetchw(const void *ptr)
 122{
 123        __asm__ __volatile__(
 124                ".arch_extension        mp\n"
 125                __ALT_SMP_ASM(
 126                        "pldw\t%a0",
 127                        "pld\t%a0"
 128                )
 129                :: "p" (ptr));
 130}
 131#endif
 132#endif
 133
 134#endif
 135
 136#endif /* __ASM_ARM_PROCESSOR_H */
 137