2 * arch/score/kernel/process.c
4 * Score Processor version.
6 * Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
7 * Chen Liqin <liqin.chen@sunplusct.com>
8 * Lennox Wu <lennox.wu@sunplusct.com>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, see the file COPYING, or write
22 * to the Free Software Foundation, Inc.,
23 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
26 #include <linux/module.h>
27 #include <linux/reboot.h>
28 #include <linux/elfcore.h>
30 #include <linux/rcupdate.h>
31 #include <linux/sched/task.h>
33 void (*pm_power_off)(void);
34 EXPORT_SYMBOL(pm_power_off);
36 /* If or when software machine-restart is implemented, add code here. */
37 void machine_restart(char *command) {}
39 /* If or when software machine-halt is implemented, add code here. */
40 void machine_halt(void) {}
42 /* If or when software machine-power-off is implemented, add code here. */
43 void machine_power_off(void) {}
45 void ret_from_fork(void);
46 void ret_from_kernel_thread(void);
48 void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long sp)
52 /* New thread loses kernel privileges. */
53 status = regs->cp0_psr & ~(KU_MASK);
55 regs->cp0_psr = status;
61 * When a process does an "exec", machine state like FPU and debug
62 * registers need to be reset. This is a hook function for that.
63 * Currently we don't have any such state to reset, so this is empty.
65 void flush_thread(void) {}
68 * set up the kernel stack and exception frames for a new process
70 int copy_thread(unsigned long clone_flags, unsigned long usp,
71 unsigned long arg, struct task_struct *p)
73 struct thread_info *ti = task_thread_info(p);
74 struct pt_regs *childregs = task_pt_regs(p);
75 struct pt_regs *regs = current_pt_regs();
77 p->thread.reg0 = (unsigned long) childregs;
78 if (unlikely(p->flags & PF_KTHREAD)) {
79 memset(childregs, 0, sizeof(struct pt_regs));
80 p->thread.reg12 = usp;
81 p->thread.reg13 = arg;
82 p->thread.reg3 = (unsigned long) ret_from_kernel_thread;
84 *childregs = *current_pt_regs();
85 childregs->regs[7] = 0; /* Clear error flag */
86 childregs->regs[4] = 0; /* Child gets zero as return value */
88 childregs->regs[0] = usp; /* user fork */
89 p->thread.reg3 = (unsigned long) ret_from_fork;
92 p->thread.cp0_psr = 0;
97 /* Fill in the fpu structure for a core dump. */
98 int dump_fpu(struct pt_regs *regs, elf_fpregset_t *r)
103 unsigned long thread_saved_pc(struct task_struct *tsk)
105 return task_pt_regs(tsk)->cp0_epc;
108 unsigned long get_wchan(struct task_struct *task)
110 if (!task || task == current || task->state == TASK_RUNNING)
113 if (!task_stack_page(task))
116 return task_pt_regs(task)->cp0_epc;
119 unsigned long arch_align_stack(unsigned long sp)