1/*
2 * Architecture-dependent parts of process handling.
3 *
4 * Copyright (C) 2013 Altera Corporation
5 * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
6 * Copyright (C) 2009 Wind River Systems Inc
7 *   Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
8 * Copyright (C) 2004 Microtronix Datacom Ltd
9 *
10 * This file is subject to the terms and conditions of the GNU General Public
11 * License.  See the file "COPYING" in the main directory of this archive
12 * for more details.
13 */
14
15#include <linux/export.h>
16#include <linux/sched.h>
17#include <linux/tick.h>
18#include <linux/uaccess.h>
19
20#include <asm/unistd.h>
21#include <asm/traps.h>
22#include <asm/cpuinfo.h>
23
24asmlinkage void ret_from_fork(void);
25asmlinkage void ret_from_kernel_thread(void);
26
27void (*pm_power_off)(void) = NULL;
28EXPORT_SYMBOL(pm_power_off);
29
30void arch_cpu_idle(void)
31{
32	local_irq_enable();
33}
34
35/*
36 * The development boards have no way to pull a board reset. Just jump to the
37 * cpu reset address and let the boot loader or the code in head.S take care of
38 * resetting peripherals.
39 */
40void machine_restart(char *__unused)
41{
42	pr_notice("Machine restart (%08x)...\n", cpuinfo.reset_addr);
43	local_irq_disable();
44	__asm__ __volatile__ (
45	"jmp	%0\n\t"
46	:
47	: "r" (cpuinfo.reset_addr)
48	: "r4");
49}
50
51void machine_halt(void)
52{
53	pr_notice("Machine halt...\n");
54	local_irq_disable();
55	for (;;)
56		;
57}
58
59/*
60 * There is no way to power off the development boards. So just spin for now. If
61 * we ever have a way of resetting a board using a GPIO we should add that here.
62 */
63void machine_power_off(void)
64{
65	pr_notice("Machine power off...\n");
66	local_irq_disable();
67	for (;;)
68		;
69}
70
71void show_regs(struct pt_regs *regs)
72{
73	pr_notice("\n");
74	show_regs_print_info(KERN_DEFAULT);
75
76	pr_notice("r1: %08lx r2: %08lx r3: %08lx r4: %08lx\n",
77		regs->r1,  regs->r2,  regs->r3,  regs->r4);
78
79	pr_notice("r5: %08lx r6: %08lx r7: %08lx r8: %08lx\n",
80		regs->r5,  regs->r6,  regs->r7,  regs->r8);
81
82	pr_notice("r9: %08lx r10: %08lx r11: %08lx r12: %08lx\n",
83		regs->r9,  regs->r10, regs->r11, regs->r12);
84
85	pr_notice("r13: %08lx r14: %08lx r15: %08lx\n",
86		regs->r13, regs->r14, regs->r15);
87
88	pr_notice("ra: %08lx fp:  %08lx sp: %08lx gp: %08lx\n",
89		regs->ra,  regs->fp,  regs->sp,  regs->gp);
90
91	pr_notice("ea: %08lx estatus: %08lx\n",
92		regs->ea,  regs->estatus);
93}
94
95void flush_thread(void)
96{
97}
98
99int copy_thread(unsigned long clone_flags,
100		unsigned long usp, unsigned long arg, struct task_struct *p)
101{
102	struct pt_regs *childregs = task_pt_regs(p);
103	struct pt_regs *regs;
104	struct switch_stack *stack;
105	struct switch_stack *childstack =
106		((struct switch_stack *)childregs) - 1;
107
108	if (unlikely(p->flags & PF_KTHREAD)) {
109		memset(childstack, 0,
110			sizeof(struct switch_stack) + sizeof(struct pt_regs));
111
112		childstack->r16 = usp;		/* fn */
113		childstack->r17 = arg;
114		childstack->ra = (unsigned long) ret_from_kernel_thread;
115		childregs->estatus = STATUS_PIE;
116		childregs->sp = (unsigned long) childstack;
117
118		p->thread.ksp = (unsigned long) childstack;
119		p->thread.kregs = childregs;
120		return 0;
121	}
122
123	regs = current_pt_regs();
124	*childregs = *regs;
125	childregs->r2 = 0;	/* Set the return value for the child. */
126	childregs->r7 = 0;
127
128	stack = ((struct switch_stack *) regs) - 1;
129	*childstack = *stack;
130	childstack->ra = (unsigned long)ret_from_fork;
131	p->thread.kregs = childregs;
132	p->thread.ksp = (unsigned long) childstack;
133
134	if (usp)
135		childregs->sp = usp;
136
137	/* Initialize tls register. */
138	if (clone_flags & CLONE_SETTLS)
139		childstack->r23 = regs->r8;
140
141	return 0;
142}
143
144/*
145 *	Generic dumping code. Used for panic and debug.
146 */
147void dump(struct pt_regs *fp)
148{
149	unsigned long	*sp;
150	unsigned char	*tp;
151	int		i;
152
153	pr_emerg("\nCURRENT PROCESS:\n\n");
154	pr_emerg("COMM=%s PID=%d\n", current->comm, current->pid);
155
156	if (current->mm) {
157		pr_emerg("TEXT=%08x-%08x DATA=%08x-%08x BSS=%08x-%08x\n",
158			(int) current->mm->start_code,
159			(int) current->mm->end_code,
160			(int) current->mm->start_data,
161			(int) current->mm->end_data,
162			(int) current->mm->end_data,
163			(int) current->mm->brk);
164		pr_emerg("USER-STACK=%08x  KERNEL-STACK=%08x\n\n",
165			(int) current->mm->start_stack,
166			(int)(((unsigned long) current) + THREAD_SIZE));
167	}
168
169	pr_emerg("PC: %08lx\n", fp->ea);
170	pr_emerg("SR: %08lx    SP: %08lx\n",
171		(long) fp->estatus, (long) fp);
172
173	pr_emerg("r1: %08lx    r2: %08lx    r3: %08lx\n",
174		fp->r1, fp->r2, fp->r3);
175
176	pr_emerg("r4: %08lx    r5: %08lx    r6: %08lx    r7: %08lx\n",
177		fp->r4, fp->r5, fp->r6, fp->r7);
178	pr_emerg("r8: %08lx    r9: %08lx    r10: %08lx    r11: %08lx\n",
179		fp->r8, fp->r9, fp->r10, fp->r11);
180	pr_emerg("r12: %08lx  r13: %08lx    r14: %08lx    r15: %08lx\n",
181		fp->r12, fp->r13, fp->r14, fp->r15);
182	pr_emerg("or2: %08lx   ra: %08lx     fp: %08lx    sp: %08lx\n",
183		fp->orig_r2, fp->ra, fp->fp, fp->sp);
184	pr_emerg("\nUSP: %08x   TRAPFRAME: %08x\n",
185		(unsigned int) fp->sp, (unsigned int) fp);
186
187	pr_emerg("\nCODE:");
188	tp = ((unsigned char *) fp->ea) - 0x20;
189	for (sp = (unsigned long *) tp, i = 0; (i < 0x40);  i += 4) {
190		if ((i % 0x10) == 0)
191			pr_emerg("\n%08x: ", (int) (tp + i));
192		pr_emerg("%08x ", (int) *sp++);
193	}
194	pr_emerg("\n");
195
196	pr_emerg("\nKERNEL STACK:");
197	tp = ((unsigned char *) fp) - 0x40;
198	for (sp = (unsigned long *) tp, i = 0; (i < 0xc0); i += 4) {
199		if ((i % 0x10) == 0)
200			pr_emerg("\n%08x: ", (int) (tp + i));
201		pr_emerg("%08x ", (int) *sp++);
202	}
203	pr_emerg("\n");
204	pr_emerg("\n");
205
206	pr_emerg("\nUSER STACK:");
207	tp = (unsigned char *) (fp->sp - 0x10);
208	for (sp = (unsigned long *) tp, i = 0; (i < 0x80); i += 4) {
209		if ((i % 0x10) == 0)
210			pr_emerg("\n%08x: ", (int) (tp + i));
211		pr_emerg("%08x ", (int) *sp++);
212	}
213	pr_emerg("\n\n");
214}
215
216unsigned long get_wchan(struct task_struct *p)
217{
218	unsigned long fp, pc;
219	unsigned long stack_page;
220	int count = 0;
221
222	if (!p || p == current || p->state == TASK_RUNNING)
223		return 0;
224
225	stack_page = (unsigned long)p;
226	fp = ((struct switch_stack *)p->thread.ksp)->fp;	/* ;dgt2 */
227	do {
228		if (fp < stack_page+sizeof(struct task_struct) ||
229			fp >= 8184+stack_page)	/* ;dgt2;tmp */
230			return 0;
231		pc = ((unsigned long *)fp)[1];
232		if (!in_sched_functions(pc))
233			return pc;
234		fp = *(unsigned long *) fp;
235	} while (count++ < 16);		/* ;dgt2;tmp */
236	return 0;
237}
238
239/*
240 * Do necessary setup to start up a newly executed thread.
241 * Will startup in user mode (status_extension = 0).
242 */
243void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long sp)
244{
245	memset((void *) regs, 0, sizeof(struct pt_regs));
246	regs->estatus = ESTATUS_EPIE | ESTATUS_EU;
247	regs->ea = pc;
248	regs->sp = sp;
249}
250
251#include <linux/elfcore.h>
252
253/* Fill in the FPU structure for a core dump. */
254int dump_fpu(struct pt_regs *regs, elf_fpregset_t *r)
255{
256	return 0; /* Nios2 has no FPU and thus no FPU registers */
257}
258