1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * linux/arch/h8300/kernel/process.c
4 *
5 * Yoshinori Sato <ysato@users.sourceforge.jp>
6 *
7 * Based on:
8 *
9 * linux/arch/m68knommu/kernel/process.c
10 *
11 * Copyright (C) 1998 D. Jeff Dionne <jeff@ryeham.ee.ryerson.ca>,
12 * Kenneth Albanowski <kjahds@kjahds.com>,
13 * The Silver Hammer Group, Ltd.
14 *
15 * linux/arch/m68k/kernel/process.c
16 *
17 * Copyright (C) 1995 Hamish Macdonald
18 *
19 * 68060 fixes by Jesper Skov
20 */
21
22 /*
23 * This file handles the architecture-dependent parts of process handling..
24 */
25
26 #include <linux/errno.h>
27 #include <linux/module.h>
28 #include <linux/sched.h>
29 #include <linux/sched/debug.h>
30 #include <linux/sched/task.h>
31 #include <linux/sched/task_stack.h>
32 #include <linux/kernel.h>
33 #include <linux/mm.h>
34 #include <linux/smp.h>
35 #include <linux/stddef.h>
36 #include <linux/unistd.h>
37 #include <linux/ptrace.h>
38 #include <linux/user.h>
39 #include <linux/interrupt.h>
40 #include <linux/reboot.h>
41 #include <linux/fs.h>
42 #include <linux/slab.h>
43 #include <linux/rcupdate.h>
44
45 #include <linux/uaccess.h>
46 #include <asm/traps.h>
47 #include <asm/setup.h>
48 #include <asm/pgtable.h>
49
50 void (*pm_power_off)(void) = NULL;
51 EXPORT_SYMBOL(pm_power_off);
52
53 asmlinkage void ret_from_fork(void);
54 asmlinkage void ret_from_kernel_thread(void);
55
56 /*
57 * The idle loop on an H8/300..
58 */
arch_cpu_idle(void)59 void arch_cpu_idle(void)
60 {
61 local_irq_enable();
62 __asm__("sleep");
63 }
64
machine_restart(char * __unused)65 void machine_restart(char *__unused)
66 {
67 local_irq_disable();
68 __asm__("jmp @@0");
69 }
70
machine_halt(void)71 void machine_halt(void)
72 {
73 local_irq_disable();
74 __asm__("sleep");
75 for (;;)
76 ;
77 }
78
machine_power_off(void)79 void machine_power_off(void)
80 {
81 local_irq_disable();
82 __asm__("sleep");
83 for (;;)
84 ;
85 }
86
show_regs(struct pt_regs * regs)87 void show_regs(struct pt_regs *regs)
88 {
89 show_regs_print_info(KERN_DEFAULT);
90
91 pr_notice("\n");
92 pr_notice("PC: %08lx Status: %02x\n",
93 regs->pc, regs->ccr);
94 pr_notice("ORIG_ER0: %08lx ER0: %08lx ER1: %08lx\n",
95 regs->orig_er0, regs->er0, regs->er1);
96 pr_notice("ER2: %08lx ER3: %08lx ER4: %08lx ER5: %08lx\n",
97 regs->er2, regs->er3, regs->er4, regs->er5);
98 pr_notice("ER6' %08lx ", regs->er6);
99 if (user_mode(regs))
100 printk("USP: %08lx\n", rdusp());
101 else
102 printk("\n");
103 }
104
flush_thread(void)105 void flush_thread(void)
106 {
107 }
108
copy_thread(unsigned long clone_flags,unsigned long usp,unsigned long topstk,struct task_struct * p)109 int copy_thread(unsigned long clone_flags,
110 unsigned long usp, unsigned long topstk,
111 struct task_struct *p)
112 {
113 struct pt_regs *childregs;
114
115 childregs = (struct pt_regs *) (THREAD_SIZE + task_stack_page(p)) - 1;
116
117 if (unlikely(p->flags & PF_KTHREAD)) {
118 memset(childregs, 0, sizeof(struct pt_regs));
119 childregs->retpc = (unsigned long) ret_from_kernel_thread;
120 childregs->er4 = topstk; /* arg */
121 childregs->er5 = usp; /* fn */
122 } else {
123 *childregs = *current_pt_regs();
124 childregs->er0 = 0;
125 childregs->retpc = (unsigned long) ret_from_fork;
126 p->thread.usp = usp ?: rdusp();
127 }
128 p->thread.ksp = (unsigned long)childregs;
129
130 return 0;
131 }
132
get_wchan(struct task_struct * p)133 unsigned long get_wchan(struct task_struct *p)
134 {
135 unsigned long fp, pc;
136 unsigned long stack_page;
137 int count = 0;
138
139 if (!p || p == current || p->state == TASK_RUNNING)
140 return 0;
141
142 stack_page = (unsigned long)p;
143 fp = ((struct pt_regs *)p->thread.ksp)->er6;
144 do {
145 if (fp < stack_page+sizeof(struct thread_info) ||
146 fp >= 8184+stack_page)
147 return 0;
148 pc = ((unsigned long *)fp)[1];
149 if (!in_sched_functions(pc))
150 return pc;
151 fp = *(unsigned long *) fp;
152 } while (count++ < 16);
153 return 0;
154 }
155
156 /* generic sys_clone is not enough registers */
sys_clone(unsigned long __user * args)157 asmlinkage int sys_clone(unsigned long __user *args)
158 {
159 unsigned long clone_flags;
160 unsigned long newsp;
161 uintptr_t parent_tidptr;
162 uintptr_t child_tidptr;
163
164 get_user(clone_flags, &args[0]);
165 get_user(newsp, &args[1]);
166 get_user(parent_tidptr, &args[2]);
167 get_user(child_tidptr, &args[3]);
168 return do_fork(clone_flags, newsp, 0,
169 (int __user *)parent_tidptr, (int __user *)child_tidptr);
170 }
171