summaryrefslogtreecommitdiff
path: root/arch/csky/kernel/process.c
blob: 8ed20028b1609e129918c3415e884543affdc108 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
// 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 esp, pc;
	unsigned long stack_page;
	int count = 0;

	if (!p || p == current || p->state == TASK_RUNNING)
		return 0;

	stack_page = (unsigned long)p;
	esp = p->thread.esp0;
	do {
		if (esp < stack_page+sizeof(struct task_struct) ||
		    esp >= 8184+stack_page)
			return 0;
		/*FIXME: There's may be error here!*/
		pc = ((unsigned long *)esp)[1];
		/* FIXME: This depends on the order of these functions. */
		if (!in_sched_functions(pc))
			return pc;
		esp = *(unsigned long *) esp;
	} while (count++ < 16);
	return 0;
}
EXPORT_SYMBOL(get_wchan);

#ifndef CONFIG_CPU_PM_NONE
void 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