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/sched.h>
  6#include <linux/sched/task_stack.h>
  7#include <linux/sched/debug.h>
  8#include <linux/delay.h>
  9#include <linux/kallsyms.h>
 10#include <linux/uaccess.h>
 11#include <linux/ptrace.h>
 12#include <linux/elfcore.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(struct task_struct *p, const struct kernel_clone_args *args)
 34{
 35	unsigned long clone_flags = args->flags;
 36	unsigned long usp = args->stack;
 37	unsigned long tls = args->tls;
 38	struct switch_stack *childstack;
 39	struct pt_regs *childregs = task_pt_regs(p);
 40
 41#ifdef CONFIG_CPU_HAS_FPU
 42	save_to_user_fp(&p->thread.user_fp);
 43#endif
 44
 45	childstack = ((struct switch_stack *) childregs) - 1;
 46	memset(childstack, 0, sizeof(struct switch_stack));
 47
 48	/* setup thread.sp for switch_to !!! */
 49	p->thread.sp = (unsigned long)childstack;
 50
 51	if (unlikely(args->fn)) {
 52		memset(childregs, 0, sizeof(struct pt_regs));
 53		childstack->r15 = (unsigned long) ret_from_kernel_thread;
 54		childstack->r10 = (unsigned long) args->fn_arg;
 55		childstack->r9 = (unsigned long) args->fn;
 56		childregs->sr = mfcr("psr");
 57	} else {
 58		*childregs = *(current_pt_regs());
 59		if (usp)
 60			childregs->usp = usp;
 61		if (clone_flags & CLONE_SETTLS)
 62			task_thread_info(p)->tp_value = childregs->tls
 63						      = tls;
 64
 65		childregs->a0 = 0;
 66		childstack->r15 = (unsigned long) ret_from_fork;
 67	}
 68
 69	return 0;
 70}
 71
 72/* Fill in the fpu structure for a core dump.  */
 73int elf_core_copy_task_fpregs(struct task_struct *t, elf_fpregset_t *fpu)
 74{
 75	memcpy(fpu, &current->thread.user_fp, sizeof(*fpu));
 76	return 1;
 77}
 78
 79int dump_task_regs(struct task_struct *tsk, elf_gregset_t *pr_regs)
 80{
 81	struct pt_regs *regs = task_pt_regs(tsk);
 82
 83	/* NOTE: usp is error value. */
 84	ELF_CORE_COPY_REGS((*pr_regs), regs)
 85
 86	return 1;
 87}
 88
 89#ifndef CONFIG_CPU_PM_NONE
 90void arch_cpu_idle(void)
 91{
 92#ifdef CONFIG_CPU_PM_WAIT
 93	asm volatile("wait\n");
 94#endif
 95
 96#ifdef CONFIG_CPU_PM_DOZE
 97	asm volatile("doze\n");
 98#endif
 99
100#ifdef CONFIG_CPU_PM_STOP
101	asm volatile("stop\n");
102#endif
103}
104#endif