diff options
Diffstat (limited to 'arch/mn10300/kernel/process.c')
| -rw-r--r-- | arch/mn10300/kernel/process.c | 297 |
1 files changed, 297 insertions, 0 deletions
diff --git a/arch/mn10300/kernel/process.c b/arch/mn10300/kernel/process.c new file mode 100644 index 00000000000..3b0d579fc15 --- /dev/null +++ b/arch/mn10300/kernel/process.c @@ -0,0 +1,297 @@ +/* MN10300 Process handling code + * + * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ +#include <linux/module.h> +#include <linux/errno.h> +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/smp.h> +#include <linux/smp_lock.h> +#include <linux/stddef.h> +#include <linux/unistd.h> +#include <linux/ptrace.h> +#include <linux/slab.h> +#include <linux/user.h> +#include <linux/a.out.h> +#include <linux/interrupt.h> +#include <linux/delay.h> +#include <linux/reboot.h> +#include <linux/percpu.h> +#include <linux/err.h> +#include <linux/fs.h> +#include <asm/uaccess.h> +#include <asm/pgtable.h> +#include <asm/system.h> +#include <asm/io.h> +#include <asm/processor.h> +#include <asm/mmu_context.h> +#include <asm/fpu.h> +#include <asm/reset-regs.h> +#include <asm/gdb-stub.h> +#include "internal.h" + +/* + * power management idle function, if any.. + */ +void (*pm_idle)(void); +EXPORT_SYMBOL(pm_idle); + +/* + * return saved PC of a blocked thread. + */ +unsigned long thread_saved_pc(struct task_struct *tsk) +{ + return ((unsigned long *) tsk->thread.sp)[3]; +} + +/* + * power off function, if any + */ +void (*pm_power_off)(void); +EXPORT_SYMBOL(pm_power_off); + +/* + * we use this if we don't have any better idle routine + */ +static void default_idle(void) +{ + local_irq_disable(); + if (!need_resched()) + safe_halt(); + else + local_irq_enable(); +} + +/* + * the idle thread + * - there's no useful work to be done, so just try to conserve power and have + * a low exit latency (ie sit in a loop waiting for somebody to say that + * they'd like to reschedule) + */ +void cpu_idle(void) +{ + int cpu = smp_processor_id(); + + /* endless idle loop with no priority at all */ + for (;;) { + while (!need_resched()) { + void (*idle)(void); + + smp_rmb(); + idle = pm_idle; + if (!idle) + idle = default_idle; + + irq_stat[cpu].idle_timestamp = jiffies; + idle(); + } + + preempt_enable_no_resched(); + schedule(); + preempt_disable(); + } +} + +void release_segments(struct mm_struct *mm) +{ +} + +void machine_restart(char *cmd) +{ +#ifdef CONFIG_GDBSTUB + gdbstub_exit(0); +#endif + +#ifdef mn10300_unit_hard_reset + mn10300_unit_hard_reset(); +#else + mn10300_proc_hard_reset(); +#endif +} + +void machine_halt(void) +{ +#ifdef CONFIG_GDBSTUB + gdbstub_exit(0); +#endif +} + +void machine_power_off(void) +{ +#ifdef CONFIG_GDBSTUB + gdbstub_exit(0); +#endif +} + +void show_regs(struct pt_regs *regs) +{ +} + +/* + * create a kernel thread + */ +int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags) +{ + struct pt_regs regs; + + memset(®s, 0, sizeof(regs)); + + regs.a2 = (unsigned long) fn; + regs.d2 = (unsigned long) arg; + regs.pc = (unsigned long) kernel_thread_helper; + local_save_flags(regs.epsw); + regs.epsw |= EPSW_IE | EPSW_IM_7; + + /* Ok, create the new process.. */ + return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, ®s, 0, + NULL, NULL); +} + +/* + * free current thread data structures etc.. + */ +void exit_thread(void) +{ + exit_fpu(); +} + +void flush_thread(void) +{ + flush_fpu(); +} + +void release_thread(struct task_struct *dead_task) +{ +} + +/* + * we do not have to muck with descriptors here, that is + * done in switch_mm() as needed. + */ +void copy_segments(struct task_struct *p, struct mm_struct *new_mm) +{ +} + +/* + * this gets called before we allocate a new thread and copy the current task + * into it so that we can store lazy state into memory + */ +void prepare_to_copy(struct task_struct *tsk) +{ + unlazy_fpu(tsk); +} + +/* + * set up the kernel stack for a new thread and copy arch-specific thread + * control information + */ +int copy_thread(int nr, unsigned long clone_flags, + unsigned long c_usp, unsigned long ustk_size, + struct task_struct *p, struct pt_regs *kregs) +{ + struct pt_regs *c_uregs, *c_kregs, *uregs; + unsigned long c_ksp; + + uregs = current->thread.uregs; + + c_ksp = (unsigned long) task_stack_page(p) + THREAD_SIZE; + + /* allocate the userspace exception frame and set it up */ + c_ksp -= sizeof(struct pt_regs); + c_uregs = (struct pt_regs *) c_ksp; + + p->thread.uregs = c_uregs; + *c_uregs = *uregs; + c_uregs->sp = c_usp; + c_uregs->epsw &= ~EPSW_FE; /* my FPU */ + + c_ksp -= 12; /* allocate function call ABI slack */ + + /* the new TLS pointer is passed in as arg #5 to sys_clone() */ + if (clone_flags & CLONE_SETTLS) + c_uregs->e2 = __frame->d3; + + /* set up the return kernel frame if called from kernel_thread() */ + c_kregs = c_uregs; + if (kregs != uregs) { + c_ksp -= sizeof(struct pt_regs); + c_kregs = (struct pt_regs *) c_ksp; + *c_kregs = *kregs; + c_kregs->sp = c_usp; + c_kregs->next = c_uregs; +#ifdef CONFIG_MN10300_CURRENT_IN_E2 + c_kregs->e2 = (unsigned long) p; /* current */ +#endif + + c_ksp -= 12; /* allocate function call ABI slack */ + } + + /* set up things up so the scheduler can start the new task */ + p->thread.__frame = c_kregs; + p->thread.a3 = (unsigned long) c_kregs; + p->thread.sp = c_ksp; + p->thread.pc = (unsigned long) ret_from_fork; + p->thread.wchan = (unsigned long) ret_from_fork; + p->thread.usp = c_usp; + + return 0; +} + +/* + * clone a process + * - tlsptr is retrieved by copy_thread() from __frame->d3 + */ +asmlinkage long sys_clone(unsigned long clone_flags, unsigned long newsp, + int __user *parent_tidptr, int __user *child_tidptr, + int __user *tlsptr) +{ + return do_fork(clone_flags, newsp ?: __frame->sp, __frame, 0, + parent_tidptr, child_tidptr); +} + +asmlinkage long sys_fork(void) +{ + return do_fork(SIGCHLD, __frame->sp, __frame, 0, NULL, NULL); +} + +asmlinkage long sys_vfork(void) +{ + return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, __frame->sp, __frame, + 0, NULL, NULL); +} + +asmlinkage long sys_execve(char __user *name, + char __user * __user *argv, + char __user * __user *envp) +{ + char *filename; + int error; + + lock_kernel(); + + filename = getname(name); + error = PTR_ERR(filename); + if (!IS_ERR(filename)) { + error = do_execve(filename, argv, envp, __frame); + if (error == 0) + current->ptrace &= ~PT_DTRACE; + + putname(filename); + } + + unlock_kernel(); + return error; +} + +unsigned long get_wchan(struct task_struct *p) +{ + return p->thread.wchan; +} |