// SPDX-License-Identifier: GPL-2.0// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. #include <linux/module.h>#include <linux/version.h>#include <linux/sched.h>#include <linux/sched/task_stack.h>#include <linux/sched/debug.h>#include <linux/delay.h>#include <linux/kallsyms.h>#include <linux/uaccess.h>#include <linux/ptrace.h> #include <asm/elf.h>#include <abi/reg_ops.h> struct cpuinfo_csky cpu_data[NR_CPUS]; asmlinkage void ret_from_fork(void);asmlinkage void ret_from_kernel_thread(void); /* * Some archs flush debug and FPU info here */void flush_thread(void){} /* * Return saved PC from a blocked thread */unsigned long thread_saved_pc(struct task_struct *tsk){	struct switch_stack *sw = (struct switch_stack *)tsk->thread.ksp; 	return sw->r15;} int copy_thread(unsigned long clone_flags,		unsigned long usp,		unsigned long kthread_arg,		struct task_struct *p){	struct switch_stack *childstack;	struct pt_regs *childregs = task_pt_regs(p); #ifdef CONFIG_CPU_HAS_FPU	save_to_user_fp(&p->thread.user_fp);#endif 	childstack = ((struct switch_stack *) childregs) - 1;	memset(childstack, 0, sizeof(struct switch_stack)); 	/* setup ksp for switch_to !!! */	p->thread.ksp = (unsigned long)childstack; 	if (unlikely(p->flags & PF_KTHREAD)) {		memset(childregs, 0, sizeof(struct pt_regs));		childstack->r15 = (unsigned long) ret_from_kernel_thread;		childstack->r8 = kthread_arg;		childstack->r9 = usp;		childregs->sr = mfcr("psr");	} else {		*childregs = *(current_pt_regs());		if (usp)			childregs->usp = usp;		if (clone_flags & CLONE_SETTLS)			task_thread_info(p)->tp_value = childregs->tls						      = childregs->regs[0]; 		childregs->a0 = 0;		childstack->r15 = (unsigned long) ret_from_fork;	} 	return 0;} /* Fill in the fpu structure for a core dump.  */int dump_fpu(struct pt_regs *regs, struct user_fp *fpu){	memcpy(fpu, &current->thread.user_fp, sizeof(*fpu));	return 1;}EXPORT_SYMBOL(dump_fpu); int dump_task_regs(struct task_struct *tsk, elf_gregset_t *pr_regs){	struct pt_regs *regs = task_pt_regs(tsk); 	/* NOTE: usp is error value. */	ELF_CORE_COPY_REGS((*pr_regs), regs) 	return 1;} unsigned long get_wchan(struct task_struct *p){	unsigned long lr;	unsigned long *fp, *stack_start, *stack_end;	int count = 0; 	if (!p || p == current || p->state == TASK_RUNNING)		return 0; 	stack_start = (unsigned long *)end_of_stack(p);	stack_end = (unsigned long *)(task_stack_page(p) + THREAD_SIZE); 	fp = (unsigned long *) thread_saved_fp(p);	do {		if (fp < stack_start || fp > stack_end)			return 0;#ifdef CONFIG_STACKTRACE		lr = fp[1];		fp = (unsigned long *)fp[0];#else		lr = *fp++;#endif		if (!in_sched_functions(lr) &&		    __kernel_text_address(lr))			return lr;	} while (count++ < 16); 	return 0;}EXPORT_SYMBOL(get_wchan); #ifndef CONFIG_CPU_PM_NONEvoid arch_cpu_idle(void){#ifdef CONFIG_CPU_PM_WAIT	asm volatile("wait\n");#endif #ifdef CONFIG_CPU_PM_DOZE	asm volatile("doze\n");#endif #ifdef CONFIG_CPU_PM_STOP	asm volatile("stop\n");#endif	local_irq_enable();}#endif