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
49 void (*pm_power_off)(void) = NULL;
50 EXPORT_SYMBOL(pm_power_off);
51
52 asmlinkage void ret_from_fork(void);
53 asmlinkage void ret_from_kernel_thread(void);
54
55 /*
56 * The idle loop on an H8/300..
57 */
arch_cpu_idle(void)58 void arch_cpu_idle(void)
59 {
60 raw_local_irq_enable();
61 __asm__("sleep");
62 }
63
machine_restart(char * __unused)64 void machine_restart(char *__unused)
65 {
66 local_irq_disable();
67 __asm__("jmp @@0");
68 }
69
machine_halt(void)70 void machine_halt(void)
71 {
72 local_irq_disable();
73 __asm__("sleep");
74 for (;;)
75 ;
76 }
77
machine_power_off(void)78 void machine_power_off(void)
79 {
80 local_irq_disable();
81 __asm__("sleep");
82 for (;;)
83 ;
84 }
85
show_regs(struct pt_regs * regs)86 void show_regs(struct pt_regs *regs)
87 {
88 show_regs_print_info(KERN_DEFAULT);
89
90 pr_notice("\n");
91 pr_notice("PC: %08lx Status: %02x\n",
92 regs->pc, regs->ccr);
93 pr_notice("ORIG_ER0: %08lx ER0: %08lx ER1: %08lx\n",
94 regs->orig_er0, regs->er0, regs->er1);
95 pr_notice("ER2: %08lx ER3: %08lx ER4: %08lx ER5: %08lx\n",
96 regs->er2, regs->er3, regs->er4, regs->er5);
97 pr_notice("ER6' %08lx ", regs->er6);
98 if (user_mode(regs))
99 printk("USP: %08lx\n", rdusp());
100 else
101 printk("\n");
102 }
103
flush_thread(void)104 void flush_thread(void)
105 {
106 }
107
copy_thread(unsigned long clone_flags,unsigned long usp,unsigned long topstk,struct task_struct * p,unsigned long tls)108 int copy_thread(unsigned long clone_flags, unsigned long usp,
109 unsigned long topstk, struct task_struct *p, unsigned long tls)
110 {
111 struct pt_regs *childregs;
112
113 childregs = (struct pt_regs *) (THREAD_SIZE + task_stack_page(p)) - 1;
114
115 if (unlikely(p->flags & (PF_KTHREAD | PF_IO_WORKER))) {
116 memset(childregs, 0, sizeof(struct pt_regs));
117 childregs->retpc = (unsigned long) ret_from_kernel_thread;
118 childregs->er4 = topstk; /* arg */
119 childregs->er5 = usp; /* fn */
120 } else {
121 *childregs = *current_pt_regs();
122 childregs->er0 = 0;
123 childregs->retpc = (unsigned long) ret_from_fork;
124 p->thread.usp = usp ?: rdusp();
125 }
126 p->thread.ksp = (unsigned long)childregs;
127
128 return 0;
129 }
130
__get_wchan(struct task_struct * p)131 unsigned long __get_wchan(struct task_struct *p)
132 {
133 unsigned long fp, pc;
134 unsigned long stack_page;
135 int count = 0;
136
137 stack_page = (unsigned long)p;
138 fp = ((struct pt_regs *)p->thread.ksp)->er6;
139 do {
140 if (fp < stack_page+sizeof(struct thread_info) ||
141 fp >= 8184+stack_page)
142 return 0;
143 pc = ((unsigned long *)fp)[1];
144 if (!in_sched_functions(pc))
145 return pc;
146 fp = *(unsigned long *) fp;
147 } while (count++ < 16);
148 return 0;
149 }
150
151 /* generic sys_clone is not enough registers */
sys_clone(unsigned long __user * args)152 asmlinkage int sys_clone(unsigned long __user *args)
153 {
154 unsigned long clone_flags;
155 unsigned long newsp;
156 uintptr_t parent_tidptr;
157 uintptr_t child_tidptr;
158 struct kernel_clone_args kargs = {};
159
160 get_user(clone_flags, &args[0]);
161 get_user(newsp, &args[1]);
162 get_user(parent_tidptr, &args[2]);
163 get_user(child_tidptr, &args[3]);
164
165 kargs.flags = (lower_32_bits(clone_flags) & ~CSIGNAL);
166 kargs.pidfd = (int __user *)parent_tidptr;
167 kargs.child_tid = (int __user *)child_tidptr;
168 kargs.parent_tid = (int __user *)parent_tidptr;
169 kargs.exit_signal = (lower_32_bits(clone_flags) & CSIGNAL);
170 kargs.stack = newsp;
171
172 return kernel_clone(&kargs);
173 }
174