Chen Liqin | 6bc9a39 | 2009-06-12 22:01:00 +0800 | [diff] [blame] | 1 | /* |
| 2 | * arch/score/kernel/process.c |
| 3 | * |
| 4 | * Score Processor version. |
| 5 | * |
| 6 | * Copyright (C) 2009 Sunplus Core Technology Co., Ltd. |
| 7 | * Chen Liqin <liqin.chen@sunplusct.com> |
| 8 | * Lennox Wu <lennox.wu@sunplusct.com> |
| 9 | * |
| 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. |
| 14 | * |
| 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. |
| 19 | * |
| 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 |
| 24 | */ |
| 25 | |
| 26 | #include <linux/module.h> |
Arnd Bergmann | 9fb24cc | 2009-06-27 14:50:51 +0200 | [diff] [blame] | 27 | #include <linux/reboot.h> |
| 28 | #include <linux/elfcore.h> |
| 29 | #include <linux/pm.h> |
Frederic Weisbecker | 0ee23fd | 2012-08-22 17:27:34 +0200 | [diff] [blame] | 30 | #include <linux/rcupdate.h> |
Chen Liqin | 6bc9a39 | 2009-06-12 22:01:00 +0800 | [diff] [blame] | 31 | |
| 32 | void (*pm_power_off)(void); |
| 33 | EXPORT_SYMBOL(pm_power_off); |
| 34 | |
| 35 | /* If or when software machine-restart is implemented, add code here. */ |
| 36 | void machine_restart(char *command) {} |
| 37 | |
| 38 | /* If or when software machine-halt is implemented, add code here. */ |
| 39 | void machine_halt(void) {} |
| 40 | |
| 41 | /* If or when software machine-power-off is implemented, add code here. */ |
| 42 | void machine_power_off(void) {} |
| 43 | |
Chen Liqin | 0402c91 | 2009-06-19 13:53:49 +0800 | [diff] [blame] | 44 | void ret_from_fork(void); |
Al Viro | 1856ab6 | 2012-10-15 15:26:11 -0400 | [diff] [blame] | 45 | void ret_from_kernel_thread(void); |
Chen Liqin | 6bc9a39 | 2009-06-12 22:01:00 +0800 | [diff] [blame] | 46 | |
| 47 | void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long sp) |
| 48 | { |
| 49 | unsigned long status; |
| 50 | |
| 51 | /* New thread loses kernel privileges. */ |
| 52 | status = regs->cp0_psr & ~(KU_MASK); |
| 53 | status |= KU_USER; |
| 54 | regs->cp0_psr = status; |
| 55 | regs->cp0_epc = pc; |
| 56 | regs->regs[0] = sp; |
| 57 | } |
| 58 | |
| 59 | void exit_thread(void) {} |
| 60 | |
| 61 | /* |
| 62 | * When a process does an "exec", machine state like FPU and debug |
| 63 | * registers need to be reset. This is a hook function for that. |
| 64 | * Currently we don't have any such state to reset, so this is empty. |
| 65 | */ |
| 66 | void flush_thread(void) {} |
| 67 | |
| 68 | /* |
| 69 | * set up the kernel stack and exception frames for a new process |
| 70 | */ |
| 71 | int copy_thread(unsigned long clone_flags, unsigned long usp, |
Al Viro | afa86fc | 2012-10-22 22:51:14 -0400 | [diff] [blame] | 72 | unsigned long arg, struct task_struct *p) |
Chen Liqin | 6bc9a39 | 2009-06-12 22:01:00 +0800 | [diff] [blame] | 73 | { |
| 74 | struct thread_info *ti = task_thread_info(p); |
| 75 | struct pt_regs *childregs = task_pt_regs(p); |
Al Viro | afa86fc | 2012-10-22 22:51:14 -0400 | [diff] [blame] | 76 | struct pt_regs *regs = current_pt_regs(); |
Chen Liqin | 6bc9a39 | 2009-06-12 22:01:00 +0800 | [diff] [blame] | 77 | |
Al Viro | 1856ab6 | 2012-10-15 15:26:11 -0400 | [diff] [blame] | 78 | p->thread.reg0 = (unsigned long) childregs; |
Al Viro | eda9697 | 2012-10-21 16:44:57 -0400 | [diff] [blame] | 79 | if (unlikely(p->flags & PF_KTHREAD)) { |
Al Viro | 1856ab6 | 2012-10-15 15:26:11 -0400 | [diff] [blame] | 80 | memset(childregs, 0, sizeof(struct pt_regs)); |
Lennox Wu | 5fbbf8a | 2013-09-14 13:48:37 +0800 | [diff] [blame] | 81 | p->thread.reg12 = usp; |
| 82 | p->thread.reg13 = arg; |
Al Viro | 1856ab6 | 2012-10-15 15:26:11 -0400 | [diff] [blame] | 83 | p->thread.reg3 = (unsigned long) ret_from_kernel_thread; |
Chen Liqin | 6bc9a39 | 2009-06-12 22:01:00 +0800 | [diff] [blame] | 84 | } else { |
Al Viro | eda9697 | 2012-10-21 16:44:57 -0400 | [diff] [blame] | 85 | *childregs = *current_pt_regs(); |
Al Viro | 1856ab6 | 2012-10-15 15:26:11 -0400 | [diff] [blame] | 86 | childregs->regs[7] = 0; /* Clear error flag */ |
| 87 | childregs->regs[4] = 0; /* Child gets zero as return value */ |
Al Viro | eda9697 | 2012-10-21 16:44:57 -0400 | [diff] [blame] | 88 | if (usp) |
| 89 | childregs->regs[0] = usp; /* user fork */ |
Al Viro | 1856ab6 | 2012-10-15 15:26:11 -0400 | [diff] [blame] | 90 | p->thread.reg3 = (unsigned long) ret_from_fork; |
Chen Liqin | 6bc9a39 | 2009-06-12 22:01:00 +0800 | [diff] [blame] | 91 | } |
| 92 | |
Chen Liqin | 6bc9a39 | 2009-06-12 22:01:00 +0800 | [diff] [blame] | 93 | p->thread.cp0_psr = 0; |
| 94 | |
| 95 | return 0; |
| 96 | } |
| 97 | |
| 98 | /* Fill in the fpu structure for a core dump. */ |
| 99 | int dump_fpu(struct pt_regs *regs, elf_fpregset_t *r) |
| 100 | { |
| 101 | return 1; |
| 102 | } |
| 103 | |
Chen Liqin | 6bc9a39 | 2009-06-12 22:01:00 +0800 | [diff] [blame] | 104 | unsigned long thread_saved_pc(struct task_struct *tsk) |
| 105 | { |
| 106 | return task_pt_regs(tsk)->cp0_epc; |
| 107 | } |
| 108 | |
| 109 | unsigned long get_wchan(struct task_struct *task) |
| 110 | { |
| 111 | if (!task || task == current || task->state == TASK_RUNNING) |
| 112 | return 0; |
| 113 | |
| 114 | if (!task_stack_page(task)) |
| 115 | return 0; |
| 116 | |
| 117 | return task_pt_regs(task)->cp0_epc; |
| 118 | } |
| 119 | |
| 120 | unsigned long arch_align_stack(unsigned long sp) |
| 121 | { |
| 122 | return sp; |
| 123 | } |