diff options
Diffstat (limited to 'arch/cris/arch-v10/kernel/process.c')
| -rw-r--r-- | arch/cris/arch-v10/kernel/process.c | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/arch/cris/arch-v10/kernel/process.c b/arch/cris/arch-v10/kernel/process.c new file mode 100644 index 000000000..02b783457 --- /dev/null +++ b/arch/cris/arch-v10/kernel/process.c @@ -0,0 +1,193 @@ +/* + * linux/arch/cris/kernel/process.c + * + * Copyright (C) 1995 Linus Torvalds + * Copyright (C) 2000-2002 Axis Communications AB + * + * Authors: Bjorn Wesen (bjornw@axis.com) + * Mikael Starvik (starvik@axis.com) + * + * This file handles the architecture-dependent parts of process handling.. + */ + +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/err.h> +#include <linux/fs.h> +#include <arch/svinto.h> +#include <linux/init.h> +#include <arch/system.h> +#include <linux/ptrace.h> + +#ifdef CONFIG_ETRAX_GPIO +void etrax_gpio_wake_up_check(void); /* drivers/gpio.c */ +#endif + +/* + * We use this if we don't have any better + * idle routine.. + */ +void default_idle(void) +{ +#ifdef CONFIG_ETRAX_GPIO + etrax_gpio_wake_up_check(); +#endif + local_irq_enable(); +} + +/* + * Free current thread data structures etc.. + */ + +void exit_thread(void) +{ + /* Nothing needs to be done. */ +} + +/* if the watchdog is enabled, we can simply disable interrupts and go + * into an eternal loop, and the watchdog will reset the CPU after 0.1s + * if on the other hand the watchdog wasn't enabled, we just enable it and wait + */ + +void hard_reset_now (void) +{ + /* + * Don't declare this variable elsewhere. We don't want any other + * code to know about it than the watchdog handler in entry.S and + * this code, implementing hard reset through the watchdog. + */ +#if defined(CONFIG_ETRAX_WATCHDOG) + extern int cause_of_death; +#endif + + printk("*** HARD RESET ***\n"); + local_irq_disable(); + +#if defined(CONFIG_ETRAX_WATCHDOG) + cause_of_death = 0xbedead; +#else + /* Since we dont plan to keep on resetting the watchdog, + the key can be arbitrary hence three */ + *R_WATCHDOG = IO_FIELD(R_WATCHDOG, key, 3) | + IO_STATE(R_WATCHDOG, enable, start); +#endif + + while(1) /* waiting for RETRIBUTION! */ ; +} + +/* + * Return saved PC of a blocked thread. + */ +unsigned long thread_saved_pc(struct task_struct *t) +{ + return task_pt_regs(t)->irp; +} + +/* setup the child's kernel stack with a pt_regs and switch_stack on it. + * it will be un-nested during _resume and _ret_from_sys_call when the + * new thread is scheduled. + * + * also setup the thread switching structure which is used to keep + * thread-specific data during _resumes. + * + */ +asmlinkage void ret_from_fork(void); +asmlinkage void ret_from_kernel_thread(void); + +int copy_thread(unsigned long clone_flags, unsigned long usp, + unsigned long arg, struct task_struct *p) +{ + struct pt_regs *childregs = task_pt_regs(p); + struct switch_stack *swstack = ((struct switch_stack *)childregs) - 1; + + /* put the pt_regs structure at the end of the new kernel stack page and fix it up + * remember that the task_struct doubles as the kernel stack for the task + */ + + if (unlikely(p->flags & PF_KTHREAD)) { + memset(swstack, 0, + sizeof(struct switch_stack) + sizeof(struct pt_regs)); + swstack->r1 = usp; + swstack->r2 = arg; + childregs->dccr = 1 << I_DCCR_BITNR; + swstack->return_ip = (unsigned long) ret_from_kernel_thread; + p->thread.ksp = (unsigned long) swstack; + p->thread.usp = 0; + return 0; + } + *childregs = *current_pt_regs(); /* struct copy of pt_regs */ + + childregs->r10 = 0; /* child returns 0 after a fork/clone */ + + /* put the switch stack right below the pt_regs */ + + swstack->r9 = 0; /* parameter to ret_from_sys_call, 0 == dont restart the syscall */ + + /* we want to return into ret_from_sys_call after the _resume */ + + swstack->return_ip = (unsigned long) ret_from_fork; /* Will call ret_from_sys_call */ + + /* fix the user-mode stackpointer */ + + p->thread.usp = usp ?: rdusp(); + + /* and the kernel-mode one */ + + p->thread.ksp = (unsigned long) swstack; + +#ifdef DEBUG + printk("copy_thread: new regs at 0x%p, as shown below:\n", childregs); + show_registers(childregs); +#endif + + return 0; +} + +unsigned long get_wchan(struct task_struct *p) +{ +#if 0 + /* YURGH. TODO. */ + + unsigned long ebp, esp, eip; + unsigned long stack_page; + int count = 0; + if (!p || p == current || p->state == TASK_RUNNING) + return 0; + stack_page = (unsigned long)p; + esp = p->thread.esp; + if (!stack_page || esp < stack_page || esp > 8188+stack_page) + return 0; + /* include/asm-i386/system.h:switch_to() pushes ebp last. */ + ebp = *(unsigned long *) esp; + do { + if (ebp < stack_page || ebp > 8184+stack_page) + return 0; + eip = *(unsigned long *) (ebp+4); + if (!in_sched_functions(eip)) + return eip; + ebp = *(unsigned long *) ebp; + } while (count++ < 16); +#endif + return 0; +} +#undef last_sched +#undef first_sched + +void show_regs(struct pt_regs * regs) +{ + unsigned long usp = rdusp(); + + show_regs_print_info(KERN_DEFAULT); + + printk("IRP: %08lx SRP: %08lx DCCR: %08lx USP: %08lx MOF: %08lx\n", + regs->irp, regs->srp, regs->dccr, usp, regs->mof ); + printk(" r0: %08lx r1: %08lx r2: %08lx r3: %08lx\n", + regs->r0, regs->r1, regs->r2, regs->r3); + printk(" r4: %08lx r5: %08lx r6: %08lx r7: %08lx\n", + regs->r4, regs->r5, regs->r6, regs->r7); + printk(" r8: %08lx r9: %08lx r10: %08lx r11: %08lx\n", + regs->r8, regs->r9, regs->r10, regs->r11); + printk("r12: %08lx r13: %08lx oR10: %08lx\n", + regs->r12, regs->r13, regs->orig_r10); +} + |