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-rw-r--r--arch/arm/kernel/process.c86
1 files changed, 61 insertions, 25 deletions
diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c
index 75316f0dd02..971d65c253a 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)