diff options
| -rw-r--r-- | arch/arm/kernel/process.c | 50 |
1 files changed, 40 insertions, 10 deletions
diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index eeb3e16c604..423bb201945 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -92,17 +92,23 @@ static int __init hlt_setup(char *__unused) __setup("nohlt", nohlt_setup); __setup("hlt", hlt_setup); -void soft_restart(unsigned long addr) +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. - */ + /* Take out a flat memory mapping. */ setup_mm_for_reboot(); /* Clean and invalidate caches */ @@ -114,7 +120,31 @@ void soft_restart(unsigned long addr) /* Push out any further dirty data, and ensure cache is empty */ flush_cache_all(); - cpu_reset(addr); + /* 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(); } void arm_machine_restart(char mode, const char *cmd) |