aboutsummaryrefslogtreecommitdiffstats
path: root/arch/nds32/kernel/process.c
blob: e01ad5d1722450f2f4b54e16e615b4c9cf4dea40 (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
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
// SPDX-License-Identifier: GPL-2.0
// Copyright (C) 2005-2017 Andes Technology Corporation

#include <linux/sched.h>
#include <linux/sched/debug.h>
#include <linux/sched/task_stack.h>
#include <linux/delay.h>
#include <linux/kallsyms.h>
#include <linux/uaccess.h>
#include <asm/elf.h>
#include <asm/proc-fns.h>
#include <asm/fpu.h>
#include <linux/ptrace.h>
#include <linux/reboot.h>

#if IS_ENABLED(CONFIG_LAZY_FPU)
struct task_struct *last_task_used_math;
#endif

extern void setup_mm_for_reboot(char mode);

extern inline void arch_reset(char mode)
{
	if (mode == 's') {
		/* Use cpu handler, jump to 0 */
		cpu_reset(0);
	}
}

void (*pm_power_off) (void);
EXPORT_SYMBOL(pm_power_off);

static char reboot_mode_nds32 = 'h';

int __init reboot_setup(char *str)
{
	reboot_mode_nds32 = str[0];
	return 1;
}

static int cpub_pwroff(void)
{
	return 0;
}

__setup("reboot=", reboot_setup);

void machine_halt(void)
{
	cpub_pwroff();
}

EXPORT_SYMBOL(machine_halt);

void machine_power_off(void)
{
	if (pm_power_off)
		pm_power_off();
}

EXPORT_SYMBOL(machine_power_off);

void machine_restart(char *cmd)
{
	/*
	 * Clean and disable cache, and turn off interrupts
	 */
	cpu_proc_fin();

	/*
	 * Tell the mm system that we are going to reboot -
	 * we may need it to insert some 1:1 mappings so that
	 * soft boot works.
	 */
	setup_mm_for_reboot(reboot_mode_nds32);

	/* Execute kernel restart handler call chain */
	do_kernel_restart(cmd);

	/*
	 * Now call the architecture specific reboot code.
	 */
	arch_reset(reboot_mode_nds32);

	/*
	 * Whoops - the architecture was unable to reboot.
	 * Tell the user!
	 */
	mdelay(1000);
	pr_info("Reboot failed -- System halted\n");
	while (1) ;
}

EXPORT_SYMBOL(machine_restart);

void show_regs(struct pt_regs *regs)
{
	printk("PC is at %pS\n", (void *)instruction_pointer(regs));
	printk("LP is at %pS\n", (void *)regs->lp);
	pr_info("pc : [<%08lx>]    lp : [<%08lx>]    %s\n"
		"sp : %08lx  fp : %08lx  gp : %08lx\n",
		instruction_pointer(regs),
		regs->lp, print_tainted(), regs->sp, regs->fp, regs->gp);
	pr_info("r25: %08lx  r24: %08lx\n", regs->uregs[25], regs->uregs[24]);

	pr_info("r23: %08lx  r22: %08lx  r21: %08lx  r20: %08lx\n",
		regs->uregs[23], regs->uregs[22],
		regs->uregs[21], regs->uregs[20]);
	pr_info("r19: %08lx  r18: %08lx  r17: %08lx  r16: %08lx\n",
		regs->uregs[19], regs->uregs[18],
		regs->uregs[17], regs->uregs[16]);
	pr_info("r15: %08lx  r14: %08lx  r13: %08lx  r12: %08lx\n",
		regs->uregs[15], regs->uregs[14],
		regs->uregs[13], regs->uregs[12]);
	pr_info("r11: %08lx  r10: %08lx  r9 : %08lx  r8 : %08lx\n",
		regs->uregs[11], regs->uregs[10],
		regs->uregs[9], regs->uregs[8]);
	pr_info("r7 : %08lx  r6 : %08lx  r5 : %08lx  r4 : %08lx\n",
		regs->uregs[7], regs->uregs[6], regs->uregs[5], regs->uregs[4]);
	pr_info("r3 : %08lx  r2 : %08lx  r1 : %08lx  r0 : %08lx\n",
		regs->uregs[3], regs->uregs[2], regs->uregs[1], regs->uregs[0]);
	pr_info("  IRQs o%s  Segment %s\n",
		interrupts_enabled(regs) ? "n" : "ff",
		uaccess_kernel() ? "kernel" : "user");
}

EXPORT_SYMBOL(show_regs);

void exit_thread(struct task_struct *tsk)
{
#if defined(CONFIG_FPU) && defined(CONFIG_LAZY_FPU)
	if (last_task_used_math == tsk)
		last_task_used_math = NULL;
#endif
}

void flush_thread(void)
{
#if defined(CONFIG_FPU)
	clear_fpu(task_pt_regs(current));
	clear_used_math();
# ifdef CONFIG_LAZY_FPU
	if (last_task_used_math == current)
		last_task_used_math = NULL;
# endif
#endif
}

DEFINE_PER_CPU(struct task_struct *, __entry_task);

asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
int copy_thread(unsigned long clone_flags, unsigned long stack_start,
		unsigned long stk_sz, struct task_struct *p, unsigned long tls)
{
	struct pt_regs *childregs = task_pt_regs(p);

	memset(&p->thread.cpu_context, 0, sizeof(struct cpu_context));

	if (unlikely(p->flags & PF_KTHREAD)) {
		memset(childregs, 0, sizeof(struct pt_regs));
		/* kernel thread fn */
		p->thread.cpu_context.r6 = stack_start;
		/* kernel thread argument */
		p->thread.cpu_context.r7 = stk_sz;
	} else {
		*childregs = *current_pt_regs();
		if (stack_start)
			childregs->sp = stack_start;
		/* child get zero as ret. */
		childregs->uregs[0] = 0;
		childregs->osp = 0;
		if (clone_flags & CLONE_SETTLS)
			childregs->uregs[25] = tls;
	}
	/* cpu context switching  */
	p->thread.cpu_context.pc = (unsigned long)ret_from_fork;
	p->thread.cpu_context.sp = (unsigned long)childregs;

#if IS_ENABLED(CONFIG_FPU)
	if (used_math()) {
# if !IS_ENABLED(CONFIG_LAZY_FPU)
		unlazy_fpu(current);
# else
		preempt_disable();
		if (last_task_used_math == current)
			save_fpu(current);
		preempt_enable();
# endif
		p->thread.fpu = current->thread.fpu;
		clear_fpu(task_pt_regs(p));
		set_stopped_child_used_math(p);
	}
#endif

#ifdef CONFIG_HWZOL
	childregs->lb = 0;
	childregs->le = 0;
	childregs->lc = 0;
#endif

	return 0;
}

#if IS_ENABLED(CONFIG_FPU)
struct task_struct *_switch_fpu(struct task_struct *prev, struct task_struct *next)
{
#if !IS_ENABLED(CONFIG_LAZY_FPU)
	unlazy_fpu(prev);
#endif
	if (!(next->flags & PF_KTHREAD))
		clear_fpu(task_pt_regs(next));
	return prev;
}
#endif

/*
 * fill in the fpe structure for a core dump...
 */
int dump_fpu(struct pt_regs *regs, elf_fpregset_t * fpu)
{
	int fpvalid = 0;
#if IS_ENABLED(CONFIG_FPU)
	struct task_struct *tsk = current;

	fpvalid = tsk_used_math(tsk);
	if (fpvalid) {
		lose_fpu();
		memcpy(fpu, &tsk->thread.fpu, sizeof(*fpu));
	}
#endif
	return fpvalid;
}

EXPORT_SYMBOL(dump_fpu);

unsigned long get_wchan(struct task_struct *p)
{
	unsigned long fp, lr;
	unsigned long stack_start, stack_end;
	int count = 0;

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

	if (IS_ENABLED(CONFIG_FRAME_POINTER)) {
		stack_start = (unsigned long)end_of_stack(p);
		stack_end = (unsigned long)task_stack_page(p) + THREAD_SIZE;

		fp = thread_saved_fp(p);
		do {
			if (fp < stack_start || fp > stack_end)
				return 0;
			lr = ((unsigned long *)fp)[0];
			if (!in_sched_functions(lr))
				return lr;
			fp = *(unsigned long *)(fp + 4);
		} while (count++ < 16);
	}
	return 0;
}

EXPORT_SYMBOL(get_wchan);

Privacy Policy