diff options
Diffstat (limited to 'arch/arm/kernel/process.c')
-rw-r--r-- | arch/arm/kernel/process.c | 394 |
1 files changed, 394 insertions, 0 deletions
diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c new file mode 100644 index 0000000..d3ea6fa --- /dev/null +++ b/arch/arm/kernel/process.c @@ -0,0 +1,394 @@ +/* + * linux/arch/arm/kernel/process.c + * + * Copyright (C) 1996-2000 Russell King - Converted to ARM. + * Original Copyright (C) 1995 Linus Torvalds + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include <stdarg.h> + +#include <linux/module.h> +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/stddef.h> +#include <linux/unistd.h> +#include <linux/slab.h> +#include <linux/user.h> +#include <linux/delay.h> +#include <linux/reboot.h> +#include <linux/interrupt.h> +#include <linux/kallsyms.h> +#include <linux/init.h> +#include <linux/cpu.h> +#include <linux/elfcore.h> +#include <linux/pm.h> +#include <linux/tick.h> +#include <linux/utsname.h> +#include <linux/uaccess.h> + +#include <asm/leds.h> +#include <asm/processor.h> +#include <asm/system.h> +#include <asm/thread_notify.h> +#include <asm/mach/time.h> + +static const char *processor_modes[] = { + "USER_26", "FIQ_26" , "IRQ_26" , "SVC_26" , "UK4_26" , "UK5_26" , "UK6_26" , "UK7_26" , + "UK8_26" , "UK9_26" , "UK10_26", "UK11_26", "UK12_26", "UK13_26", "UK14_26", "UK15_26", + "USER_32", "FIQ_32" , "IRQ_32" , "SVC_32" , "UK4_32" , "UK5_32" , "UK6_32" , "ABT_32" , + "UK8_32" , "UK9_32" , "UK10_32", "UND_32" , "UK12_32", "UK13_32", "UK14_32", "SYS_32" +}; + +static const char *isa_modes[] = { + "ARM" , "Thumb" , "Jazelle", "ThumbEE" +}; + +extern void setup_mm_for_reboot(char mode); + +static volatile int hlt_counter; + +#include <mach/system.h> + +void disable_hlt(void) +{ + hlt_counter++; +} + +EXPORT_SYMBOL(disable_hlt); + +void enable_hlt(void) +{ + hlt_counter--; +} + +EXPORT_SYMBOL(enable_hlt); + +static int __init nohlt_setup(char *__unused) +{ + hlt_counter = 1; + return 1; +} + +static int __init hlt_setup(char *__unused) +{ + hlt_counter = 0; + return 1; +} + +__setup("nohlt", nohlt_setup); +__setup("hlt", hlt_setup); + +void arm_machine_restart(char mode) +{ + /* + * Clean and disable cache, and turn off interrupts + */ + cpu_proc_fin(); + + /* + * Tell the mm system that we are going to reboot - + * we may need it to insert some 1:1 mappings so that + * soft boot works. + */ + setup_mm_for_reboot(mode); + + /* + * Now call the architecture specific reboot code. + */ + arch_reset(mode); + + /* + * Whoops - the architecture was unable to reboot. + * Tell the user! + */ + mdelay(1000); + printk("Reboot failed -- System halted\n"); + while (1); +} + +/* + * Function pointers to optional machine specific functions + */ +void (*pm_idle)(void); +EXPORT_SYMBOL(pm_idle); + +void (*pm_power_off)(void); +EXPORT_SYMBOL(pm_power_off); + +void (*arm_pm_restart)(char str) = arm_machine_restart; +EXPORT_SYMBOL_GPL(arm_pm_restart); + + +/* + * This is our default idle handler. We need to disable + * interrupts here to ensure we don't miss a wakeup call. + */ +static void default_idle(void) +{ + if (hlt_counter) + cpu_relax(); + else { + local_irq_disable(); + if (!need_resched()) + arch_idle(); + local_irq_enable(); + } +} + +/* + * The idle thread. We try to conserve power, while trying to keep + * overall latency low. The architecture specific idle is passed + * a value to indicate the level of "idleness" of the system. + */ +void cpu_idle(void) +{ + local_fiq_enable(); + + /* endless idle loop with no priority at all */ + while (1) { + void (*idle)(void) = pm_idle; + +#ifdef CONFIG_HOTPLUG_CPU + if (cpu_is_offline(smp_processor_id())) { + leds_event(led_idle_start); + cpu_die(); + } +#endif + + if (!idle) + idle = default_idle; + leds_event(led_idle_start); + tick_nohz_stop_sched_tick(1); + while (!need_resched()) + idle(); + leds_event(led_idle_end); + tick_nohz_restart_sched_tick(); + preempt_enable_no_resched(); + schedule(); + preempt_disable(); + } +} + +static char reboot_mode = 'h'; + +int __init reboot_setup(char *str) +{ + reboot_mode = str[0]; + return 1; +} + +__setup("reboot=", reboot_setup); + +void machine_halt(void) +{ +} + + +void machine_power_off(void) +{ + if (pm_power_off) + pm_power_off(); +} + +void machine_restart(char * __unused) +{ + arm_pm_restart(reboot_mode); +} + +void __show_regs(struct pt_regs *regs) +{ + unsigned long flags; + char buf[64]; + + printk("CPU: %d %s (%s %.*s)\n", + smp_processor_id(), print_tainted(), init_utsname()->release, + (int)strcspn(init_utsname()->version, " "), + init_utsname()->version); + print_symbol("PC is at %s\n", instruction_pointer(regs)); + print_symbol("LR is at %s\n", regs->ARM_lr); + printk("pc : [<%08lx>] lr : [<%08lx>] psr: %08lx\n" + "sp : %08lx ip : %08lx fp : %08lx\n", + regs->ARM_pc, regs->ARM_lr, regs->ARM_cpsr, + regs->ARM_sp, regs->ARM_ip, regs->ARM_fp); + printk("r10: %08lx r9 : %08lx r8 : %08lx\n", + regs->ARM_r10, regs->ARM_r9, + regs->ARM_r8); + printk("r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n", + regs->ARM_r7, regs->ARM_r6, + regs->ARM_r5, regs->ARM_r4); + printk("r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n", + regs->ARM_r3, regs->ARM_r2, + regs->ARM_r1, regs->ARM_r0); + + flags = regs->ARM_cpsr; + buf[0] = flags & PSR_N_BIT ? 'N' : 'n'; + buf[1] = flags & PSR_Z_BIT ? 'Z' : 'z'; + buf[2] = flags & PSR_C_BIT ? 'C' : 'c'; + buf[3] = flags & PSR_V_BIT ? 'V' : 'v'; + buf[4] = '\0'; + + printk("Flags: %s IRQs o%s FIQs o%s Mode %s ISA %s Segment %s\n", + buf, interrupts_enabled(regs) ? "n" : "ff", + fast_interrupts_enabled(regs) ? "n" : "ff", + processor_modes[processor_mode(regs)], + isa_modes[isa_mode(regs)], + get_fs() == get_ds() ? "kernel" : "user"); +#ifdef CONFIG_CPU_CP15 + { + unsigned int ctrl; + + buf[0] = '\0'; +#ifdef CONFIG_CPU_CP15_MMU + { + unsigned int transbase, dac; + asm("mrc p15, 0, %0, c2, c0\n\t" + "mrc p15, 0, %1, c3, c0\n" + : "=r" (transbase), "=r" (dac)); + snprintf(buf, sizeof(buf), " Table: %08x DAC: %08x", + transbase, dac); + } +#endif + asm("mrc p15, 0, %0, c1, c0\n" : "=r" (ctrl)); + + printk("Control: %08x%s\n", ctrl, buf); + } +#endif +} + +void show_regs(struct pt_regs * regs) +{ + printk("\n"); + printk("Pid: %d, comm: %20s\n", task_pid_nr(current), current->comm); + __show_regs(regs); + __backtrace(); +} + +/* + * Free current thread data structures etc.. + */ +void exit_thread(void) +{ +} + +ATOMIC_NOTIFIER_HEAD(thread_notify_head); + +EXPORT_SYMBOL_GPL(thread_notify_head); + +void flush_thread(void) +{ + struct thread_info *thread = current_thread_info(); + struct task_struct *tsk = current; + + memset(thread->used_cp, 0, sizeof(thread->used_cp)); + memset(&tsk->thread.debug, 0, sizeof(struct debug_info)); + memset(&thread->fpstate, 0, sizeof(union fp_state)); + + thread_notify(THREAD_NOTIFY_FLUSH, thread); +} + +void release_thread(struct task_struct *dead_task) +{ + struct thread_info *thread = task_thread_info(dead_task); + + thread_notify(THREAD_NOTIFY_RELEASE, thread); +} + +asmlinkage void ret_from_fork(void) __asm__("ret_from_fork"); + +int +copy_thread(int nr, unsigned long clone_flags, unsigned long stack_start, + unsigned long stk_sz, struct task_struct *p, struct pt_regs *regs) +{ + struct thread_info *thread = task_thread_info(p); + struct pt_regs *childregs = task_pt_regs(p); + + *childregs = *regs; + childregs->ARM_r0 = 0; + childregs->ARM_sp = stack_start; + + memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save)); + thread->cpu_context.sp = (unsigned long)childregs; + thread->cpu_context.pc = (unsigned long)ret_from_fork; + + if (clone_flags & CLONE_SETTLS) + thread->tp_value = regs->ARM_r3; + + return 0; +} + +/* + * fill in the fpe structure for a core dump... + */ +int dump_fpu (struct pt_regs *regs, struct user_fp *fp) +{ + struct thread_info *thread = current_thread_info(); + int used_math = thread->used_cp[1] | thread->used_cp[2]; + + if (used_math) + memcpy(fp, &thread->fpstate.soft, sizeof (*fp)); + + return used_math != 0; +} +EXPORT_SYMBOL(dump_fpu); + +/* + * Shuffle the argument into the correct register before calling the + * thread function. r1 is the thread argument, r2 is the pointer to + * the thread function, and r3 points to the exit function. + */ +extern void kernel_thread_helper(void); +asm( ".section .text\n" +" .align\n" +" .type kernel_thread_helper, #function\n" +"kernel_thread_helper:\n" +" mov r0, r1\n" +" mov lr, r3\n" +" mov pc, r2\n" +" .size kernel_thread_helper, . - kernel_thread_helper\n" +" .previous"); + +/* + * Create a kernel thread. + */ +pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags) +{ + struct pt_regs regs; + + memset(®s, 0, sizeof(regs)); + + regs.ARM_r1 = (unsigned long)arg; + regs.ARM_r2 = (unsigned long)fn; + regs.ARM_r3 = (unsigned long)do_exit; + regs.ARM_pc = (unsigned long)kernel_thread_helper; + regs.ARM_cpsr = SVC_MODE; + + return do_fork(flags|CLONE_VM|CLONE_UNTRACED, 0, ®s, 0, NULL, NULL); +} +EXPORT_SYMBOL(kernel_thread); + +unsigned long get_wchan(struct task_struct *p) +{ + unsigned long fp, lr; + unsigned long stack_start, stack_end; + int count = 0; + if (!p || p == current || p->state == TASK_RUNNING) + return 0; + + stack_start = (unsigned long)end_of_stack(p); + stack_end = (unsigned long)task_stack_page(p) + THREAD_SIZE; + + fp = thread_saved_fp(p); + do { + if (fp < stack_start || fp > stack_end) + return 0; + lr = ((unsigned long *)fp)[-1]; + if (!in_sched_functions(lr)) + return lr; + fp = *(unsigned long *) (fp - 12); + } while (count ++ < 16); + return 0; +} |