| /* |
| * 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/export.h> |
| #include <linux/sched.h> |
| #include <linux/kernel.h> |
| #include <linux/mm.h> |
| #include <linux/stddef.h> |
| #include <linux/unistd.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 <linux/random.h> |
| #include <linux/hw_breakpoint.h> |
| #include <linux/cpuidle.h> |
| #include <linux/leds.h> |
| |
| #include <asm/cacheflush.h> |
| #include <asm/idmap.h> |
| #include <asm/processor.h> |
| #include <asm/thread_notify.h> |
| #include <asm/stacktrace.h> |
| #include <asm/mach/time.h> |
| |
| #ifdef CONFIG_CC_STACKPROTECTOR |
| #include <linux/stackprotector.h> |
| unsigned long __stack_chk_guard __read_mostly; |
| EXPORT_SYMBOL(__stack_chk_guard); |
| #endif |
| |
| 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 call_with_stack(void (*fn)(void *), void *arg, void *sp); |
| typedef void (*phys_reset_t)(unsigned long); |
| |
| /* |
| * A temporary stack to use for CPU reset. This is static so that we |
| * don't clobber it with the identity mapping. When running with this |
| * stack, any references to the current task *will not work* so you |
| * should really do as little as possible before jumping to your reset |
| * code. |
| */ |
| static u64 soft_restart_stack[16]; |
| |
| static void __soft_restart(void *addr) |
| { |
| phys_reset_t phys_reset; |
| |
| /* Take out a flat memory mapping. */ |
| setup_mm_for_reboot(); |
| |
| /* Clean and invalidate caches */ |
| flush_cache_all(); |
| |
| /* Turn off caching */ |
| cpu_proc_fin(); |
| |
| /* Push out any further dirty data, and ensure cache is empty */ |
| flush_cache_all(); |
| |
| /* Switch to the identity mapping. */ |
| phys_reset = (phys_reset_t)(unsigned long)virt_to_phys(cpu_reset); |
| phys_reset((unsigned long)addr); |
| |
| /* Should never get here. */ |
| BUG(); |
| } |
| |
| void soft_restart(unsigned long addr) |
| { |
| u64 *stack = soft_restart_stack + ARRAY_SIZE(soft_restart_stack); |
| |
| /* Disable interrupts first */ |
| local_irq_disable(); |
| local_fiq_disable(); |
| |
| /* Disable the L2 if we're the last man standing. */ |
| if (num_online_cpus() == 1) |
| outer_disable(); |
| |
| /* Change to the new stack and continue with the reset. */ |
| call_with_stack(__soft_restart, (void *)addr, (void *)stack); |
| |
| /* Should never get here. */ |
| BUG(); |
| } |
| |
| static void null_restart(char mode, const char *cmd) |
| { |
| } |
| |
| /* |
| * Function pointers to optional machine specific functions |
| */ |
| void (*pm_power_off)(void); |
| EXPORT_SYMBOL(pm_power_off); |
| |
| void (*arm_pm_restart)(char str, const char *cmd) = null_restart; |
| EXPORT_SYMBOL_GPL(arm_pm_restart); |
| |
| /* |
| * This is our default idle handler. |
| */ |
| |
| void (*arm_pm_idle)(void); |
| |
| static void default_idle(void) |
| { |
| if (arm_pm_idle) |
| arm_pm_idle(); |
| else |
| cpu_do_idle(); |
| local_irq_enable(); |
| } |
| |
| void arch_cpu_idle_prepare(void) |
| { |
| local_fiq_enable(); |
| } |
| |
| void arch_cpu_idle_enter(void) |
| { |
| ledtrig_cpu(CPU_LED_IDLE_START); |
| #ifdef CONFIG_PL310_ERRATA_769419 |
| wmb(); |
| #endif |
| } |
| |
| void arch_cpu_idle_exit(void) |
| { |
| ledtrig_cpu(CPU_LED_IDLE_END); |
| } |
| |
| #ifdef CONFIG_HOTPLUG_CPU |
| void arch_cpu_idle_dead(void) |
| { |
| cpu_die(); |
| } |
| #endif |
| |
| /* |
| * Called from the core idle loop. |
| */ |
| void arch_cpu_idle(void) |
| { |
| if (cpuidle_idle_call()) |
| default_idle(); |
| } |
| |
| static char reboot_mode = 'h'; |
| |
| int __init reboot_setup(char *str) |
| { |
| reboot_mode = str[0]; |
| return 1; |
| } |
| |
| __setup("reboot=", reboot_setup); |
| |
| /* |
| * Called by kexec, immediately prior to machine_kexec(). |
| * |
| * This must completely disable all secondary CPUs; simply causing those CPUs |
| * to execute e.g. a RAM-based pin loop is not sufficient. This allows the |
| * kexec'd kernel to use any and all RAM as it sees fit, without having to |
| * avoid any code or data used by any SW CPU pin loop. The CPU hotplug |
| * functionality embodied in disable_nonboot_cpus() to achieve this. |
| */ |
| void machine_shutdown(void) |
| { |
| disable_nonboot_cpus(); |
| } |
| |
| /* |
| * Halting simply requires that the secondary CPUs stop performing any |
| * activity (executing tasks, handling interrupts). smp_send_stop() |
| * achieves this. |
| */ |
| void machine_halt(void) |
| { |
| smp_send_stop(); |
| |
| local_irq_disable(); |
| while (1); |
| } |
| |
| /* |
| * Power-off simply requires that the secondary CPUs stop performing any |
| * activity (executing tasks, handling interrupts). smp_send_stop() |
| * achieves this. When the system power is turned off, it will take all CPUs |
| * with it. |
| */ |
| void machine_power_off(void) |
| { |
| smp_send_stop(); |
| |
| if (pm_power_off) |
| pm_power_off(); |
| } |
| |
| /* |
| * Restart requires that the secondary CPUs stop performing any activity |
| * while the primary CPU resets the system. Systems with a single CPU can |
| * use soft_restart() as their machine descriptor's .restart hook, since that |
| * will cause the only available CPU to reset. Systems with multiple CPUs must |
| * provide a HW restart implementation, to ensure that all CPUs reset at once. |
| * This is required so that any code running after reset on the primary CPU |
| * doesn't have to co-ordinate with other CPUs to ensure they aren't still |
| * executing pre-reset code, and using RAM that the primary CPU's code wishes |
| * to use. Implementing such co-ordination would be essentially impossible. |
| */ |
| void machine_restart(char *cmd) |
| { |
| smp_send_stop(); |
| |
| arm_pm_restart(reboot_mode, cmd); |
| |
| /* Give a grace period for failure to restart of 1s */ |
| mdelay(1000); |
| |
| /* Whoops - the platform was unable to reboot. Tell the user! */ |
| printk("Reboot failed -- System halted\n"); |
| local_irq_disable(); |
| while (1); |
| } |
| |
| void __show_regs(struct pt_regs *regs) |
| { |
| unsigned long flags; |
| char buf[64]; |
| |
| show_regs_print_info(KERN_DEFAULT); |
| |
| 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"); |
| __show_regs(regs); |
| dump_stack(); |
| } |
| |
| ATOMIC_NOTIFIER_HEAD(thread_notify_head); |
| |
| EXPORT_SYMBOL_GPL(thread_notify_head); |
| |
| /* |
| * Free current thread data structures etc.. |
| */ |
| void exit_thread(void) |
| { |
| thread_notify(THREAD_NOTIFY_EXIT, current_thread_info()); |
| } |
| |
| void flush_thread(void) |
| { |
| struct thread_info *thread = current_thread_info(); |
| struct task_struct *tsk = current; |
| |
| flush_ptrace_hw_breakpoint(tsk); |
| |
| 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) |
| { |
| } |
| |
| asmlinkage void ret_from_fork(void) __asm__("ret_from_fork"); |
| |
| int |
| copy_thread(unsigned long clone_flags, unsigned long stack_start, |
| unsigned long stk_sz, struct task_struct *p) |
| { |
| struct thread_info *thread = task_thread_info(p); |
| struct pt_regs *childregs = task_pt_regs(p); |
| |
| memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save)); |
| |
| if (likely(!(p->flags & PF_KTHREAD))) { |
| *childregs = *current_pt_regs(); |
| childregs->ARM_r0 = 0; |
| if (stack_start) |
| childregs->ARM_sp = stack_start; |
| } else { |
| memset(childregs, 0, sizeof(struct pt_regs)); |
| thread->cpu_context.r4 = stk_sz; |
| thread->cpu_context.r5 = stack_start; |
| childregs->ARM_cpsr = SVC_MODE; |
| } |
| thread->cpu_context.pc = (unsigned long)ret_from_fork; |
| thread->cpu_context.sp = (unsigned long)childregs; |
| |
| clear_ptrace_hw_breakpoint(p); |
| |
| if (clone_flags & CLONE_SETTLS) |
| thread->tp_value = childregs->ARM_r3; |
| |
| thread_notify(THREAD_NOTIFY_COPY, thread); |
| |
| return 0; |
| } |
| |
| /* |
| * Fill in the task's elfregs structure for a core dump. |
| */ |
| int dump_task_regs(struct task_struct *t, elf_gregset_t *elfregs) |
| { |
| elf_core_copy_regs(elfregs, task_pt_regs(t)); |
| return 1; |
| } |
| |
| /* |
| * 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); |
| |
| unsigned long get_wchan(struct task_struct *p) |
| { |
| struct stackframe frame; |
| int count = 0; |
| if (!p || p == current || p->state == TASK_RUNNING) |
| return 0; |
| |
| frame.fp = thread_saved_fp(p); |
| frame.sp = thread_saved_sp(p); |
| frame.lr = 0; /* recovered from the stack */ |
| frame.pc = thread_saved_pc(p); |
| do { |
| int ret = unwind_frame(&frame); |
| if (ret < 0) |
| return 0; |
| if (!in_sched_functions(frame.pc)) |
| return frame.pc; |
| } while (count ++ < 16); |
| return 0; |
| } |
| |
| unsigned long arch_randomize_brk(struct mm_struct *mm) |
| { |
| unsigned long range_end = mm->brk + 0x02000000; |
| return randomize_range(mm->brk, range_end, 0) ? : mm->brk; |
| } |
| |
| #ifdef CONFIG_MMU |
| /* |
| * The vectors page is always readable from user space for the |
| * atomic helpers and the signal restart code. Insert it into the |
| * gate_vma so that it is visible through ptrace and /proc/<pid>/mem. |
| */ |
| static struct vm_area_struct gate_vma = { |
| .vm_start = 0xffff0000, |
| .vm_end = 0xffff0000 + PAGE_SIZE, |
| .vm_flags = VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYEXEC, |
| }; |
| |
| static int __init gate_vma_init(void) |
| { |
| gate_vma.vm_page_prot = PAGE_READONLY_EXEC; |
| return 0; |
| } |
| arch_initcall(gate_vma_init); |
| |
| struct vm_area_struct *get_gate_vma(struct mm_struct *mm) |
| { |
| return &gate_vma; |
| } |
| |
| int in_gate_area(struct mm_struct *mm, unsigned long addr) |
| { |
| return (addr >= gate_vma.vm_start) && (addr < gate_vma.vm_end); |
| } |
| |
| int in_gate_area_no_mm(unsigned long addr) |
| { |
| return in_gate_area(NULL, addr); |
| } |
| |
| const char *arch_vma_name(struct vm_area_struct *vma) |
| { |
| return (vma == &gate_vma) ? "[vectors]" : NULL; |
| } |
| #endif |