summaryrefslogtreecommitdiffstats
path: root/arch/nios2/kernel/process.c
blob: 9ff37ba2bb6032184fcf3d284b00f42f5b3b8ff5 (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
263
264
265
266
267
268
269
270
/*
 * Architecture-dependent parts of process handling.
 *
 * Copyright (C) 2013 Altera Corporation
 * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
 * Copyright (C) 2009 Wind River Systems Inc
 *   Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
 * Copyright (C) 2004 Microtronix Datacom Ltd
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 */

#include <linux/export.h>
#include <linux/sched.h>
#include <linux/sched/debug.h>
#include <linux/sched/task.h>
#include <linux/sched/task_stack.h>
#include <linux/mm_types.h>
#include <linux/tick.h>
#include <linux/uaccess.h>

#include <asm/unistd.h>
#include <asm/traps.h>
#include <asm/cpuinfo.h>

asmlinkage void ret_from_fork(void);
asmlinkage void ret_from_kernel_thread(void);

void (*pm_power_off)(void) = NULL;
EXPORT_SYMBOL(pm_power_off);

void arch_cpu_idle(void)
{
	raw_local_irq_enable();
}

/*
 * The development boards have no way to pull a board reset. Just jump to the
 * cpu reset address and let the boot loader or the code in head.S take care of
 * resetting peripherals.
 */
void machine_restart(char *__unused)
{
	pr_notice("Machine restart (%08x)...\n", cpuinfo.reset_addr);
	local_irq_disable();
	__asm__ __volatile__ (
	"jmp	%0\n\t"
	:
	: "r" (cpuinfo.reset_addr)
	: "r4");
}

void machine_halt(void)
{
	pr_notice("Machine halt...\n");
	local_irq_disable();
	for (;;)
		;
}

/*
 * There is no way to power off the development boards. So just spin for now. If
 * we ever have a way of resetting a board using a GPIO we should add that here.
 */
void machine_power_off(void)
{
	pr_notice("Machine power off...\n");
	local_irq_disable();
	for (;;)
		;
}

void show_regs(struct pt_regs *regs)
{
	pr_notice("\n");
	show_regs_print_info(KERN_DEFAULT);

	pr_notice("r1: %08lx r2: %08lx r3: %08lx r4: %08lx\n",
		regs->r1,  regs->r2,  regs->r3,  regs->r4);

	pr_notice("r5: %08lx r6: %08lx r7: %08lx r8: %08lx\n",
		regs->r5,  regs->r6,  regs->r7,  regs->r8);

	pr_notice("r9: %08lx r10: %08lx r11: %08lx r12: %08lx\n",
		regs->r9,  regs->r10, regs->r11, regs->r12);

	pr_notice("r13: %08lx r14: %08lx r15: %08lx\n",
		regs->r13, regs->r14, regs->r15);

	pr_notice("ra: %08lx fp:  %08lx sp: %08lx gp: %08lx\n",
		regs->ra,  regs->fp,  regs->sp,  regs->gp);

	pr_notice("ea: %08lx estatus: %08lx\n",
		regs->ea,  regs->estatus);
}

void flush_thread(void)
{
}

int copy_thread(unsigned long clone_flags, unsigned long usp, unsigned long arg,
		struct task_struct *p, unsigned long tls)
{
	struct pt_regs *childregs = task_pt_regs(p);
	struct pt_regs *regs;
	struct switch_stack *stack;
	struct switch_stack *childstack =
		((struct switch_stack *)childregs) - 1;

	if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
		memset(childstack, 0,
			sizeof(struct switch_stack) + sizeof(struct pt_regs));

		childstack->r16 = usp;		/* fn */
		childstack->r17 = arg;
		childstack->ra = (unsigned long) ret_from_kernel_thread;
		childregs->estatus = STATUS_PIE;
		childregs->sp = (unsigned long) childstack;

		p->thread.ksp = (unsigned long) childstack;
		p->thread.kregs = childregs;
		return 0;
	}

	regs = current_pt_regs();
	*childregs = *regs;
	childregs->r2 = 0;	/* Set the return value for the child. */
	childregs->r7 = 0;

	stack = ((struct switch_stack *) regs) - 1;
	*childstack = *stack;
	childstack->ra = (unsigned long)ret_from_fork;
	p->thread.kregs = childregs;
	p->thread.ksp = (unsigned long) childstack;

	if (usp)
		childregs->sp = usp;

	/* Initialize tls register. */
	if (clone_flags & CLONE_SETTLS)
		childstack->r23 = tls;

	return 0;
}

/*
 *	Generic dumping code. Used for panic and debug.
 */
void dump(struct pt_regs *fp)
{
	unsigned long	*sp;
	unsigned char	*tp;
	int		i;

	pr_emerg("\nCURRENT PROCESS:\n\n");
	pr_emerg("COMM=%s PID=%d\n", current->comm, current->pid);

	if (current->mm) {
		pr_emerg("TEXT=%08x-%08x DATA=%08x-%08x BSS=%08x-%08x\n",
			(int) current->mm->start_code,
			(int) current->mm->end_code,
			(int) current->mm->start_data,
			(int) current->mm->end_data,
			(int) current->mm->end_data,
			(int) current->mm->brk);
		pr_emerg("USER-STACK=%08x  KERNEL-STACK=%08x\n\n",
			(int) current->mm->start_stack,
			(int)(((unsigned long) current) + THREAD_SIZE));
	}

	pr_emerg("PC: %08lx\n", fp->ea);
	pr_emerg("SR: %08lx    SP: %08lx\n",
		(long) fp->estatus, (long) fp);

	pr_emerg("r1: %08lx    r2: %08lx    r3: %08lx\n",
		fp->r1, fp->r2, fp->r3);

	pr_emerg("r4: %08lx    r5: %08lx    r6: %08lx    r7: %08lx\n",
		fp->r4, fp->r5, fp->r6, fp->r7);
	pr_emerg("r8: %08lx    r9: %08lx    r10: %08lx    r11: %08lx\n",
		fp->r8, fp->r9, fp->r10, fp->r11);
	pr_emerg("r12: %08lx  r13: %08lx    r14: %08lx    r15: %08lx\n",
		fp->r12, fp->r13, fp->r14, fp->r15);
	pr_emerg("or2: %08lx   ra: %08lx     fp: %08lx    sp: %08lx\n",
		fp->orig_r2, fp->ra, fp->fp, fp->sp);
	pr_emerg("\nUSP: %08x   TRAPFRAME: %08x\n",
		(unsigned int) fp->sp, (unsigned int) fp);

	pr_emerg("\nCODE:");
	tp = ((unsigned char *) fp->ea) - 0x20;
	for (sp = (unsigned long *) tp, i = 0; (i < 0x40);  i += 4) {
		if ((i % 0x10) == 0)
			pr_emerg("\n%08x: ", (int) (tp + i));
		pr_emerg("%08x ", (int) *sp++);
	}
	pr_emerg("\n");

	pr_emerg("\nKERNEL STACK:");
	tp = ((unsigned char *) fp) - 0x40;
	for (sp = (unsigned long *) tp, i = 0; (i < 0xc0); i += 4) {
		if ((i % 0x10) == 0)
			pr_emerg("\n%08x: ", (int) (tp + i));
		pr_emerg("%08x ", (int) *sp++);
	}
	pr_emerg("\n");
	pr_emerg("\n");

	pr_emerg("\nUSER STACK:");
	tp = (unsigned char *) (fp->sp - 0x10);
	for (sp = (unsigned long *) tp, i = 0; (i < 0x80); i += 4) {
		if ((i % 0x10) == 0)
			pr_emerg("\n%08x: ", (int) (tp + i));
		pr_emerg("%08x ", (int) *sp++);
	}
	pr_emerg("\n\n");
}

unsigned long get_wchan(struct task_struct *p)
{
	unsigned long fp, pc;
	unsigned long stack_page;
	int count = 0;

	if (!p || p == current || task_is_running(p))
		return 0;

	stack_page = (unsigned long)p;
	fp = ((struct switch_stack *)p->thread.ksp)->fp;	/* ;dgt2 */
	do {
		if (fp < stack_page+sizeof(struct task_struct) ||
			fp >= 8184+stack_page)	/* ;dgt2;tmp */
			return 0;
		pc = ((unsigned long *)fp)[1];
		if (!in_sched_functions(pc))
			return pc;
		fp = *(unsigned long *) fp;
	} while (count++ < 16);		/* ;dgt2;tmp */
	return 0;
}

/*
 * Do necessary setup to start up a newly executed thread.
 * Will startup in user mode (status_extension = 0).
 */
void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long sp)
{
	memset((void *) regs, 0, sizeof(struct pt_regs));
	regs->estatus = ESTATUS_EPIE | ESTATUS_EU;
	regs->ea = pc;
	regs->sp = sp;
}

asmlinkage int nios2_clone(unsigned long clone_flags, unsigned long newsp,
			   int __user *parent_tidptr, int __user *child_tidptr,
			   unsigned long tls)
{
	struct kernel_clone_args args = {
		.flags		= (lower_32_bits(clone_flags) & ~CSIGNAL),
		.pidfd		= parent_tidptr,
		.child_tid	= child_tidptr,
		.parent_tid	= parent_tidptr,
		.exit_signal	= (lower_32_bits(clone_flags) & CSIGNAL),
		.stack		= newsp,
		.tls		= tls,
	};

	return kernel_clone(&args);
}