1 /* MN10300 Process handling code
3 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public Licence
8 * as published by the Free Software Foundation; either version
9 * 2 of the Licence, or (at your option) any later version.
11 #include <linux/module.h>
12 #include <linux/errno.h>
13 #include <linux/sched.h>
14 #include <linux/sched/debug.h>
15 #include <linux/sched/task.h>
16 #include <linux/kernel.h>
18 #include <linux/smp.h>
19 #include <linux/stddef.h>
20 #include <linux/unistd.h>
21 #include <linux/ptrace.h>
22 #include <linux/user.h>
23 #include <linux/interrupt.h>
24 #include <linux/delay.h>
25 #include <linux/reboot.h>
26 #include <linux/percpu.h>
27 #include <linux/err.h>
29 #include <linux/slab.h>
30 #include <linux/rcupdate.h>
31 #include <linux/uaccess.h>
32 #include <asm/pgtable.h>
34 #include <asm/processor.h>
35 #include <asm/mmu_context.h>
37 #include <asm/reset-regs.h>
38 #include <asm/gdb-stub.h>
42 * return saved PC of a blocked thread.
44 unsigned long thread_saved_pc(struct task_struct *tsk)
46 return ((unsigned long *) tsk->thread.sp)[3];
50 * power off function, if any
52 void (*pm_power_off)(void);
53 EXPORT_SYMBOL(pm_power_off);
56 * On SMP it's slightly faster (but much more power-consuming!)
57 * to poll the ->work.need_resched flag instead of waiting for the
58 * cross-CPU IPI to arrive. Use this option with caution.
60 * tglx: No idea why this depends on HOTPLUG_CPU !?!
62 #if !defined(CONFIG_SMP) || defined(CONFIG_HOTPLUG_CPU)
63 void arch_cpu_idle(void)
69 void release_segments(struct mm_struct *mm)
73 void machine_restart(char *cmd)
75 #ifdef CONFIG_KERNEL_DEBUGGER
79 #ifdef mn10300_unit_hard_reset
80 mn10300_unit_hard_reset();
82 mn10300_proc_hard_reset();
86 void machine_halt(void)
88 #ifdef CONFIG_KERNEL_DEBUGGER
93 void machine_power_off(void)
95 #ifdef CONFIG_KERNEL_DEBUGGER
100 void show_regs(struct pt_regs *regs)
102 show_regs_print_info(KERN_DEFAULT);
106 * free current thread data structures etc..
108 void exit_thread(struct task_struct *tsk)
113 void flush_thread(void)
118 void release_thread(struct task_struct *dead_task)
123 * we do not have to muck with descriptors here, that is
124 * done in switch_mm() as needed.
126 void copy_segments(struct task_struct *p, struct mm_struct *new_mm)
131 * this gets called so that we can store lazy state into memory and copy the
132 * current task into the new thread.
134 int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
142 * set up the kernel stack for a new thread and copy arch-specific thread
143 * control information
145 int copy_thread(unsigned long clone_flags,
146 unsigned long c_usp, unsigned long ustk_size,
147 struct task_struct *p)
149 struct thread_info *ti = task_thread_info(p);
150 struct pt_regs *c_regs;
153 c_ksp = (unsigned long) task_stack_page(p) + THREAD_SIZE;
155 /* allocate the userspace exception frame and set it up */
156 c_ksp -= sizeof(struct pt_regs);
157 c_regs = (struct pt_regs *) c_ksp;
158 c_ksp -= 12; /* allocate function call ABI slack */
160 /* set up things up so the scheduler can start the new task */
161 p->thread.uregs = c_regs;
163 p->thread.a3 = (unsigned long) c_regs;
164 p->thread.sp = c_ksp;
165 p->thread.wchan = p->thread.pc;
166 p->thread.usp = c_usp;
168 if (unlikely(p->flags & PF_KTHREAD)) {
169 memset(c_regs, 0, sizeof(struct pt_regs));
170 c_regs->a0 = c_usp; /* function */
171 c_regs->d0 = ustk_size; /* argument */
172 local_save_flags(c_regs->epsw);
173 c_regs->epsw |= EPSW_IE | EPSW_IM_7;
174 p->thread.pc = (unsigned long) ret_from_kernel_thread;
177 *c_regs = *current_pt_regs();
180 c_regs->epsw &= ~EPSW_FE; /* my FPU */
182 /* the new TLS pointer is passed in as arg #5 to sys_clone() */
183 if (clone_flags & CLONE_SETTLS)
184 c_regs->e2 = current_frame()->d3;
186 p->thread.pc = (unsigned long) ret_from_fork;
191 unsigned long get_wchan(struct task_struct *p)
193 return p->thread.wchan;