LXR linux/arch/csky/kernel/process.c

   1// SPDX-License-Identifier: GPL-2.0
   2// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
   3
   4#include <linux/module.h>
   5#include <linux/version.h>
   6#include <linux/sched.h>
   7#include <linux/sched/task_stack.h>
   8#include <linux/sched/debug.h>
   9#include <linux/delay.h>
  10#include <linux/kallsyms.h>
  11#include <linux/uaccess.h>
  12#include <linux/ptrace.h>
  13
  14#include <asm/elf.h>
  15#include <abi/reg_ops.h>
  16
  17struct cpuinfo_csky cpu_data[NR_CPUS];
  18
  19#ifdef CONFIG_STACKPROTECTOR
  20#include <linux/stackprotector.h>
  21unsigned long __stack_chk_guard __read_mostly;
  22EXPORT_SYMBOL(__stack_chk_guard);
  23#endif
  24
  25asmlinkage void ret_from_fork(void);
  26asmlinkage void ret_from_kernel_thread(void);
  27
  28/*
  29 * Some archs flush debug and FPU info here
  30 */
  31void flush_thread(void){}
  32
  33int copy_thread(unsigned long clone_flags,
  34                unsigned long usp,
  35                unsigned long kthread_arg,
  36                struct task_struct *p,
  37                unsigned long tls)
  38{
  39        struct switch_stack *childstack;
  40        struct pt_regs *childregs = task_pt_regs(p);
  41
  42#ifdef CONFIG_CPU_HAS_FPU
  43        save_to_user_fp(&p->thread.user_fp);
  44#endif
  45
  46        childstack = ((struct switch_stack *) childregs) - 1;
  47        memset(childstack, 0, sizeof(struct switch_stack));
  48
  49        /* setup thread.sp for switch_to !!! */
  50        p->thread.sp = (unsigned long)childstack;
  51
  52        if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
  53                memset(childregs, 0, sizeof(struct pt_regs));
  54                childstack->r15 = (unsigned long) ret_from_kernel_thread;
  55                childstack->r10 = kthread_arg;
  56                childstack->r9 = usp;
  57                childregs->sr = mfcr("psr");
  58        } else {
  59                *childregs = *(current_pt_regs());
  60                if (usp)
  61                        childregs->usp = usp;
  62                if (clone_flags & CLONE_SETTLS)
  63                        task_thread_info(p)->tp_value = childregs->tls
  64                                                      = tls;
  65
  66                childregs->a0 = 0;
  67                childstack->r15 = (unsigned long) ret_from_fork;
  68        }
  69
  70        return 0;
  71}
  72
  73/* Fill in the fpu structure for a core dump.  */
  74int dump_fpu(struct pt_regs *regs, struct user_fp *fpu)
  75{
  76        memcpy(fpu, &current->thread.user_fp, sizeof(*fpu));
  77        return 1;
  78}
  79EXPORT_SYMBOL(dump_fpu);
  80
  81int dump_task_regs(struct task_struct *tsk, elf_gregset_t *pr_regs)
  82{
  83        struct pt_regs *regs = task_pt_regs(tsk);
  84
  85        /* NOTE: usp is error value. */
  86        ELF_CORE_COPY_REGS((*pr_regs), regs)
  87
  88        return 1;
  89}
  90
  91#ifndef CONFIG_CPU_PM_NONE
  92void arch_cpu_idle(void)
  93{
  94#ifdef CONFIG_CPU_PM_WAIT
  95        asm volatile("wait\n");
  96#endif
  97
  98#ifdef CONFIG_CPU_PM_DOZE
  99        asm volatile("doze\n");
 100#endif
 101
 102#ifdef CONFIG_CPU_PM_STOP
 103        asm volatile("stop\n");
 104#endif
 105        raw_local_irq_enable();
 106}
 107#endif
 108