Quelle  processor.h   Sprache: C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
 *  arch/arm/include/asm/processor.h
 *
 *  Copyright (C) 1995-1999 Russell King
 */

#ifndef __ASM_ARM_PROCESSOR_H
#define __ASM_ARM_PROCESSOR_H

#ifdef __KERNEL__

#include <asm/hw_breakpoint.h>
#include <asm/ptrace.h>
#include <asm/types.h>
#include <asm/unified.h>
#include <asm/vdso/processor.h>

#ifdef __KERNEL__
#define STACK_TOP ((current->personality & ADDR_LIMIT_32BIT) ? \
    TASK_SIZE : TASK_SIZE_26)
#define STACK_TOP_MAX TASK_SIZE
#endif

struct debug_info {
#ifdef CONFIG_HAVE_HW_BREAKPOINT
 struct perf_event *hbp[ARM_MAX_HBP_SLOTS];
#endif
};

struct thread_struct {
       /* fault info   */
 unsigned long  address;
 unsigned long  trap_no;
 unsigned long  error_code;
       /* debugging   */
 struct debug_info debug;
};

/*
 * Everything usercopied to/from thread_struct is statically-sized, so
 * no hardened usercopy whitelist is needed.
 */
static inline void arch_thread_struct_whitelist(unsigned long *offset,
      unsigned long *size)
{
 *offset = *size = 0;
}

#define INIT_THREAD  { }

#define start_thread(regs,pc,sp)     \
({         \
 unsigned long r7, r8, r9;     \
         \
 if (IS_ENABLED(CONFIG_BINFMT_ELF_FDPIC)) {   \
  r7 = regs->ARM_r7;     \
  r8 = regs->ARM_r8;     \
  r9 = regs->ARM_r9;     \
 }        \
 memset(regs->uregs, 0, sizeof(regs->uregs));   \
 if (IS_ENABLED(CONFIG_BINFMT_ELF_FDPIC) &&   \
     current->personality & FDPIC_FUNCPTRS) {   \
  regs->ARM_r7 = r7;     \
  regs->ARM_r8 = r8;     \
  regs->ARM_r9 = r9;     \
  regs->ARM_r10 = current->mm->start_data;  \
 } else if (!IS_ENABLED(CONFIG_MMU))    \
  regs->ARM_r10 = current->mm->start_data;  \
 if (current->personality & ADDR_LIMIT_32BIT)   \
  regs->ARM_cpsr = USR_MODE;    \
 else        \
  regs->ARM_cpsr = USR26_MODE;    \
 if (elf_hwcap & HWCAP_THUMB && pc & 1)    \
  regs->ARM_cpsr |= PSR_T_BIT;    \
 regs->ARM_cpsr |= PSR_ENDSTATE;     \
 regs->ARM_pc = pc & ~1;  /* pc */ \
 regs->ARM_sp = sp;  /* sp */ \
})

/* Forward declaration, a strange C thing */
struct task_struct;

unsigned long __get_wchan(struct task_struct *p);

#define task_pt_regs(p) \
 ((struct pt_regs *)(THREAD_START_SP + task_stack_page(p)) - 1)

#define KSTK_EIP(tsk) task_pt_regs(tsk)->ARM_pc
#define KSTK_ESP(tsk) task_pt_regs(tsk)->ARM_sp

#ifdef CONFIG_SMP
#define __ALT_SMP_ASM(smp, up)      \
 "9998: " smp "\n"      \
 " .pushsection \".alt.smp.init\", \"a\"\n"  \
 " .align 2\n"      \
 " .long 9998b - .\n"     \
 " " up "\n"      \
 " .popsection\n"
#else
#define __ALT_SMP_ASM(smp, up) up
#endif

/*
 * Prefetching support - only ARMv5.
 */
#if __LINUX_ARM_ARCH__ >= 5

#define ARCH_HAS_PREFETCH
static inline void prefetch(const void *ptr)
{
 __asm__ __volatile__(
  "pld\t%a0"
  :: "p" (ptr));
}

#if __LINUX_ARM_ARCH__ >= 7 && defined(CONFIG_SMP)
#define ARCH_HAS_PREFETCHW
static inline void prefetchw(const void *ptr)
{
 __asm__ __volatile__(
  ".arch_extension mp\n"
  __ALT_SMP_ASM(
   "pldw\t%a0",
   "pld\t%a0"
  )
  :: "p" (ptr));
}
#endif
#endif

#endif

#endif /* __ASM_ARM_PROCESSOR_H */