diff options
Diffstat (limited to 'arch/arm/kernel/process.c')
-rw-r--r-- | arch/arm/kernel/process.c | 86 |
1 files changed, 61 insertions, 25 deletions
diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index 75316f0..971d65c 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -57,7 +57,7 @@ static const char *isa_modes[] = { "ARM" , "Thumb" , "Jazelle", "ThumbEE" }; -extern void setup_mm_for_reboot(char mode); +extern void setup_mm_for_reboot(void); static volatile int hlt_counter; @@ -92,18 +92,24 @@ static int __init hlt_setup(char *__unused) __setup("nohlt", nohlt_setup); __setup("hlt", hlt_setup); -void arm_machine_restart(char mode, const char *cmd) +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) { - /* Disable interrupts first */ - local_irq_disable(); - local_fiq_disable(); + phys_reset_t phys_reset; - /* - * 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); + /* Take out a flat memory mapping. */ + setup_mm_for_reboot(); /* Clean and invalidate caches */ flush_cache_all(); @@ -114,18 +120,35 @@ void arm_machine_restart(char mode, const char *cmd) /* Push out any further dirty data, and ensure cache is empty */ flush_cache_all(); - /* - * Now call the architecture specific reboot code. - */ - arch_reset(mode, cmd); + /* Switch to the identity mapping. */ + phys_reset = (phys_reset_t)(unsigned long)virt_to_phys(cpu_reset); + phys_reset((unsigned long)addr); - /* - * Whoops - the architecture was unable to reboot. - * Tell the user! - */ - mdelay(1000); - printk("Reboot failed -- System halted\n"); - while (1); + /* 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) +{ } /* @@ -134,7 +157,7 @@ void arm_machine_restart(char mode, const char *cmd) void (*pm_power_off)(void); EXPORT_SYMBOL(pm_power_off); -void (*arm_pm_restart)(char str, const char *cmd) = arm_machine_restart; +void (*arm_pm_restart)(char str, const char *cmd) = null_restart; EXPORT_SYMBOL_GPL(arm_pm_restart); static void do_nothing(void *unused) @@ -183,7 +206,8 @@ void cpu_idle(void) /* endless idle loop with no priority at all */ while (1) { - tick_nohz_stop_sched_tick(1); + tick_nohz_idle_enter(); + rcu_idle_enter(); leds_event(led_idle_start); while (!need_resched()) { #ifdef CONFIG_HOTPLUG_CPU @@ -192,6 +216,9 @@ void cpu_idle(void) #endif local_irq_disable(); +#ifdef CONFIG_PL310_ERRATA_769419 + wmb(); +#endif if (hlt_counter) { local_irq_enable(); cpu_relax(); @@ -210,7 +237,8 @@ void cpu_idle(void) } } leds_event(led_idle_end); - tick_nohz_restart_sched_tick(); + rcu_idle_exit(); + tick_nohz_idle_exit(); preempt_enable_no_resched(); schedule(); preempt_disable(); @@ -250,7 +278,15 @@ void machine_power_off(void) void machine_restart(char *cmd) { machine_shutdown(); + 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"); + while (1); } void __show_regs(struct pt_regs *regs) |