1 files changed, 278 insertions, 179 deletions

diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index cdeb727527d..7c4fada440f 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -19,14 +19,16 @@
 #include <linux/mm.h>
 #include <linux/err.h>
 #include <linux/cpu.h>
-#include <linux/smp.h>
 #include <linux/seq_file.h>
 #include <linux/irq.h>
 #include <linux/percpu.h>
 #include <linux/clockchips.h>
 #include <linux/completion.h>
+#include <linux/cpufreq.h>
+#include <linux/irq_work.h>
 
 #include <linux/atomic.h>
+#include <asm/smp.h>
 #include <asm/cacheflush.h>
 #include <asm/cpu.h>
 #include <asm/cputype.h>
@@ -40,8 +42,10 @@
 #include <asm/sections.h>
 #include <asm/tlbflush.h>
 #include <asm/ptrace.h>
-#include <asm/localtimer.h>
 #include <asm/smp_plat.h>
+#include <asm/virt.h>
+#include <asm/mach/arch.h>
+#include <asm/mpu.h>
 
 /*
  * as from 2.5, kernels no longer have an init_tasks structure
@@ -50,68 +54,70 @@
  */
 struct secondary_data secondary_data;
 
+/*
+ * control for which core is the next to come out of the secondary
+ * boot "holding pen"
+ */
+volatile int pen_release = -1;
+
 enum ipi_msg_type {
-	IPI_TIMER = 2,
+	IPI_WAKEUP,
+	IPI_TIMER,
 	IPI_RESCHEDULE,
 	IPI_CALL_FUNC,
 	IPI_CALL_FUNC_SINGLE,
 	IPI_CPU_STOP,
+	IPI_IRQ_WORK,
+	IPI_COMPLETION,
 };
 
-int __cpuinit __cpu_up(unsigned int cpu)
+static DECLARE_COMPLETION(cpu_running);
+
+static struct smp_operations smp_ops;
+
+void __init smp_set_ops(struct smp_operations *ops)
 {
-	struct cpuinfo_arm *ci = &per_cpu(cpu_data, cpu);
-	struct task_struct *idle = ci->idle;
-	int ret;
+	if (ops)
+		smp_ops = *ops;
+};
 
-	/*
-	 * Spawn a new process manually, if not already done.
-	 * Grab a pointer to its task struct so we can mess with it
-	 */
-	if (!idle) {
-		idle = fork_idle(cpu);
-		if (IS_ERR(idle)) {
-			printk(KERN_ERR "CPU%u: fork() failed\n", cpu);
-			return PTR_ERR(idle);
-		}
-		ci->idle = idle;
-	} else {
-		/*
-		 * Since this idle thread is being re-used, call
-		 * init_idle() to reinitialize the thread structure.
-		 */
-		init_idle(idle, cpu);
-	}
+static unsigned long get_arch_pgd(pgd_t *pgd)
+{
+	phys_addr_t pgdir = virt_to_idmap(pgd);
+	BUG_ON(pgdir & ARCH_PGD_MASK);
+	return pgdir >> ARCH_PGD_SHIFT;
+}
+
+int __cpu_up(unsigned int cpu, struct task_struct *idle)
+{
+	int ret;
 
 	/*
 	 * We need to tell the secondary core where to find
 	 * its stack and the page tables.
 	 */
 	secondary_data.stack = task_stack_page(idle) + THREAD_START_SP;
-	secondary_data.pgdir = virt_to_phys(idmap_pgd);
-	secondary_data.swapper_pg_dir = virt_to_phys(swapper_pg_dir);
-	__cpuc_flush_dcache_area(&secondary_data, sizeof(secondary_data));
-	outer_clean_range(__pa(&secondary_data), __pa(&secondary_data + 1));
+#ifdef CONFIG_ARM_MPU
+	secondary_data.mpu_rgn_szr = mpu_rgn_info.rgns[MPU_RAM_REGION].drsr;
+#endif
+
+#ifdef CONFIG_MMU
+	secondary_data.pgdir = get_arch_pgd(idmap_pgd);
+	secondary_data.swapper_pg_dir = get_arch_pgd(swapper_pg_dir);
+#endif
+	sync_cache_w(&secondary_data);
 
 	/*
 	 * Now bring the CPU into our world.
 	 */
 	ret = boot_secondary(cpu, idle);
 	if (ret == 0) {
-		unsigned long timeout;
-
 		/*
 		 * CPU was successfully started, wait for it
 		 * to come online or time out.
 		 */
-		timeout = jiffies + HZ;
-		while (time_before(jiffies, timeout)) {
-			if (cpu_online(cpu))
-				break;
-
-			udelay(10);
-			barrier();
-		}
+		wait_for_completion_timeout(&cpu_running,
+						 msecs_to_jiffies(1000));
 
 		if (!cpu_online(cpu)) {
 			pr_crit("CPU%u: failed to come online\n", cpu);
@@ -121,22 +127,61 @@ int __cpuinit __cpu_up(unsigned int cpu)
 		pr_err("CPU%u: failed to boot: %d\n", cpu, ret);
 	}
 
-	secondary_data.stack = NULL;
-	secondary_data.pgdir = 0;
 
+	memset(&secondary_data, 0, sizeof(secondary_data));
 	return ret;
 }
 
+/* platform specific SMP operations */
+void __init smp_init_cpus(void)
+{
+	if (smp_ops.smp_init_cpus)
+		smp_ops.smp_init_cpus();
+}
+
+int boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+	if (smp_ops.smp_boot_secondary)
+		return smp_ops.smp_boot_secondary(cpu, idle);
+	return -ENOSYS;
+}
+
+int platform_can_cpu_hotplug(void)
+{
+#ifdef CONFIG_HOTPLUG_CPU
+	if (smp_ops.cpu_kill)
+		return 1;
+#endif
+
+	return 0;
+}
+
 #ifdef CONFIG_HOTPLUG_CPU
-static void percpu_timer_stop(void);
+static int platform_cpu_kill(unsigned int cpu)
+{
+	if (smp_ops.cpu_kill)
+		return smp_ops.cpu_kill(cpu);
+	return 1;
+}
 
+static int platform_cpu_disable(unsigned int cpu)
+{
+	if (smp_ops.cpu_disable)
+		return smp_ops.cpu_disable(cpu);
+
+	/*
+	 * By default, allow disabling all CPUs except the first one,
+	 * since this is special on a lot of platforms, e.g. because
+	 * of clock tick interrupts.
+	 */
+	return cpu == 0 ? -EPERM : 0;
+}
 /*
  * __cpu_disable runs on the processor to be shutdown.
  */
 int __cpu_disable(void)
 {
 	unsigned int cpu = smp_processor_id();
-	struct task_struct *p;
 	int ret;
 
 	ret = platform_cpu_disable(cpu);
@@ -155,23 +200,16 @@ int __cpu_disable(void)
 	migrate_irqs();
 
 	/*
-	 * Stop the local timer for this CPU.
-	 */
-	percpu_timer_stop();
-
-	/*
 	 * Flush user cache and TLB mappings, and then remove this CPU
 	 * from the vm mask set of all processes.
+	 *
+	 * Caches are flushed to the Level of Unification Inner Shareable
+	 * to write-back dirty lines to unified caches shared by all CPUs.
 	 */
-	flush_cache_all();
+	flush_cache_louis();
 	local_flush_tlb_all();
 
-	read_lock(&tasklist_lock);
-	for_each_process(p) {
-		if (p->mm)
-			cpumask_clear_cpu(cpu, mm_cpumask(p->mm));
-	}
-	read_unlock(&tasklist_lock);
+	clear_tasks_mm_cpumask(cpu);
 
 	return 0;
 }
@@ -190,6 +228,13 @@ void __cpu_die(unsigned int cpu)
 	}
 	printk(KERN_NOTICE "CPU%u: shutdown\n", cpu);
 
+	/*
+	 * platform_cpu_kill() is generally expected to do the powering off
+	 * and/or cutting of clocks to the dying CPU.  Optionally, this may
+	 * be done by the CPU which is dying in preference to supporting
+	 * this call, but that means there is _no_ synchronisation between
+	 * the requesting CPU and the dying CPU actually losing power.
+	 */
 	if (!platform_cpu_kill(cpu))
 		printk("CPU%u: unable to kill\n", cpu);
 }
@@ -209,16 +254,47 @@ void __ref cpu_die(void)
 	idle_task_exit();
 
 	local_irq_disable();
-	mb();
 
-	/* Tell __cpu_die() that this CPU is now safe to dispose of */
+	/*
+	 * Flush the data out of the L1 cache for this CPU.  This must be
+	 * before the completion to ensure that data is safely written out
+	 * before platform_cpu_kill() gets called - which may disable
+	 * *this* CPU and power down its cache.
+	 */
+	flush_cache_louis();
+
+	/*
+	 * Tell __cpu_die() that this CPU is now safe to dispose of.  Once
+	 * this returns, power and/or clocks can be removed at any point
+	 * from this CPU and its cache by platform_cpu_kill().
+	 */
 	complete(&cpu_died);
 
 	/*
-	 * actual CPU shutdown procedure is at least platform (if not
-	 * CPU) specific.
+	 * Ensure that the cache lines associated with that completion are
+	 * written out.  This covers the case where _this_ CPU is doing the
+	 * powering down, to ensure that the completion is visible to the
+	 * CPU waiting for this one.
 	 */
-	platform_cpu_die(cpu);
+	flush_cache_louis();
+
+	/*
+	 * The actual CPU shutdown procedure is at least platform (if not
+	 * CPU) specific.  This may remove power, or it may simply spin.
+	 *
+	 * Platforms are generally expected *NOT* to return from this call,
+	 * although there are some which do because they have no way to
+	 * power down the CPU.  These platforms are the _only_ reason we
+	 * have a return path which uses the fragment of assembly below.
+	 *
+	 * The return path should not be used for platforms which can
+	 * power off the CPU.
+	 */
+	if (smp_ops.cpu_die)
+		smp_ops.cpu_die(cpu);
+
+	pr_warn("CPU%u: smp_ops.cpu_die() returned, trying to resuscitate\n",
+		cpu);
 
 	/*
 	 * Do not return to the idle loop - jump back to the secondary
@@ -237,11 +313,12 @@ void __ref cpu_die(void)
  * Called by both boot and secondaries to move global data into
  * per-processor storage.
  */
-static void __cpuinit smp_store_cpu_info(unsigned int cpuid)
+static void smp_store_cpu_info(unsigned int cpuid)
 {
 	struct cpuinfo_arm *cpu_info = &per_cpu(cpu_data, cpuid);
 
 	cpu_info->loops_per_jiffy = loops_per_jiffy;
+	cpu_info->cpuid = read_cpuid_id();
 
 	store_cpu_topology(cpuid);
 }
@@ -250,32 +327,41 @@ static void __cpuinit smp_store_cpu_info(unsigned int cpuid)
  * This is the secondary CPU boot entry.  We're using this CPUs
  * idle thread stack, but a set of temporary page tables.
  */
-asmlinkage void __cpuinit secondary_start_kernel(void)
+asmlinkage void secondary_start_kernel(void)
 {
 	struct mm_struct *mm = &init_mm;
-	unsigned int cpu = smp_processor_id();
+	unsigned int cpu;
 
-	printk("CPU%u: Booted secondary processor\n", cpu);
+	/*
+	 * The identity mapping is uncached (strongly ordered), so
+	 * switch away from it before attempting any exclusive accesses.
+	 */
+	cpu_switch_mm(mm->pgd, mm);
+	local_flush_bp_all();
+	enter_lazy_tlb(mm, current);
+	local_flush_tlb_all();
 
 	/*
 	 * All kernel threads share the same mm context; grab a
 	 * reference and switch to it.
 	 */
+	cpu = smp_processor_id();
 	atomic_inc(&mm->mm_count);
 	current->active_mm = mm;
 	cpumask_set_cpu(cpu, mm_cpumask(mm));
-	cpu_switch_mm(mm->pgd, mm);
-	enter_lazy_tlb(mm, current);
-	local_flush_tlb_all();
 
 	cpu_init();
+
+	printk("CPU%u: Booted secondary processor\n", cpu);
+
 	preempt_disable();
 	trace_hardirqs_off();
 
 	/*
 	 * Give the platform a chance to do its own initialisation.
 	 */
-	platform_secondary_init(cpu);
+	if (smp_ops.smp_secondary_init)
+		smp_ops.smp_secondary_init(cpu);
 
 	notify_cpu_starting(cpu);
 
@@ -286,51 +372,31 @@ asmlinkage void __cpuinit secondary_start_kernel(void)
 	/*
 	 * OK, now it's safe to let the boot CPU continue.  Wait for
 	 * the CPU migration code to notice that the CPU is online
-	 * before we continue.
+	 * before we continue - which happens after __cpu_up returns.
 	 */
 	set_cpu_online(cpu, true);
+	complete(&cpu_running);
 
-	/*
-	 * Setup the percpu timer for this CPU.
-	 */
-	percpu_timer_setup();
-
-	while (!cpu_active(cpu))
-		cpu_relax();
-
-	/*
-	 * cpu_active bit is set, so it's safe to enalbe interrupts
-	 * now.
-	 */
 	local_irq_enable();
 	local_fiq_enable();
 
 	/*
 	 * OK, it's off to the idle thread for us
 	 */
-	cpu_idle();
+	cpu_startup_entry(CPUHP_ONLINE);
 }
 
 void __init smp_cpus_done(unsigned int max_cpus)
 {
-	int cpu;
-	unsigned long bogosum = 0;
-
-	for_each_online_cpu(cpu)
-		bogosum += per_cpu(cpu_data, cpu).loops_per_jiffy;
+	printk(KERN_INFO "SMP: Total of %d processors activated.\n",
+	       num_online_cpus());
 
-	printk(KERN_INFO "SMP: Total of %d processors activated "
-	       "(%lu.%02lu BogoMIPS).\n",
-	       num_online_cpus(),
-	       bogosum / (500000/HZ),
-	       (bogosum / (5000/HZ)) % 100);
+	hyp_mode_check();
 }
 
 void __init smp_prepare_boot_cpu(void)
 {
-	unsigned int cpu = smp_processor_id();
-
-	per_cpu(cpu_data, cpu).idle = current;
+	set_my_cpu_offset(per_cpu_offset(smp_processor_id()));
 }
 
 void __init smp_prepare_cpus(unsigned int max_cpus)
@@ -348,24 +414,19 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
 		max_cpus = ncores;
 	if (ncores > 1 && max_cpus) {
 		/*
-		 * Enable the local timer or broadcast device for the
-		 * boot CPU, but only if we have more than one CPU.
-		 */
-		percpu_timer_setup();
-
-		/*
 		 * Initialise the present map, which describes the set of CPUs
 		 * actually populated at the present time. A platform should
-		 * re-initialize the map in platform_smp_prepare_cpus() if
-		 * present != possible (e.g. physical hotplug).
+		 * re-initialize the map in the platforms smp_prepare_cpus()
+		 * if present != possible (e.g. physical hotplug).
 		 */
-		init_cpu_present(&cpu_possible_map);
+		init_cpu_present(cpu_possible_mask);
 
 		/*
 		 * Initialise the SCU if there are more than one CPU
 		 * and let them know where to start.
 		 */
-		platform_smp_prepare_cpus(max_cpus);
+		if (smp_ops.smp_prepare_cpus)
+			smp_ops.smp_prepare_cpus(max_cpus);
 	}
 }
 
@@ -373,7 +434,8 @@ static void (*smp_cross_call)(const struct cpumask *, unsigned int);
 
 void __init set_smp_cross_call(void (*fn)(const struct cpumask *, unsigned int))
 {
-	smp_cross_call = fn;
+	if (!smp_cross_call)
+		smp_cross_call = fn;
 }
 
 void arch_send_call_function_ipi_mask(const struct cpumask *mask)
@@ -381,18 +443,34 @@ void arch_send_call_function_ipi_mask(const struct cpumask *mask)
 	smp_cross_call(mask, IPI_CALL_FUNC);
 }
 
+void arch_send_wakeup_ipi_mask(const struct cpumask *mask)
+{
+	smp_cross_call(mask, IPI_WAKEUP);
+}
+
 void arch_send_call_function_single_ipi(int cpu)
 {
 	smp_cross_call(cpumask_of(cpu), IPI_CALL_FUNC_SINGLE);
 }
 
+#ifdef CONFIG_IRQ_WORK
+void arch_irq_work_raise(void)
+{
+	if (is_smp())
+		smp_cross_call(cpumask_of(smp_processor_id()), IPI_IRQ_WORK);
+}
+#endif
+
 static const char *ipi_types[NR_IPI] = {
-#define S(x,s)	[x - IPI_TIMER] = s
+#define S(x,s)	[x] = s
+	S(IPI_WAKEUP, "CPU wakeup interrupts"),
 	S(IPI_TIMER, "Timer broadcast interrupts"),
 	S(IPI_RESCHEDULE, "Rescheduling interrupts"),
 	S(IPI_CALL_FUNC, "Function call interrupts"),
 	S(IPI_CALL_FUNC_SINGLE, "Single function call interrupts"),
 	S(IPI_CPU_STOP, "CPU stop interrupts"),
+	S(IPI_IRQ_WORK, "IRQ work interrupts"),
+	S(IPI_COMPLETION, "completion interrupts"),
 };
 
 void show_ipi_list(struct seq_file *p, int prec)
@@ -402,7 +480,7 @@ void show_ipi_list(struct seq_file *p, int prec)
 	for (i = 0; i < NR_IPI; i++) {
 		seq_printf(p, "%*s%u: ", prec - 1, "IPI", i);
 
-		for_each_present_cpu(cpu)
+		for_each_online_cpu(cpu)
 			seq_printf(p, "%10u ",
 				   __get_irq_stat(cpu, ipi_irqs[i]));
 
@@ -421,69 +499,11 @@ u64 smp_irq_stat_cpu(unsigned int cpu)
 	return sum;
 }
 
-/*
- * Timer (local or broadcast) support
- */
-static DEFINE_PER_CPU(struct clock_event_device, percpu_clockevent);
-
-static void ipi_timer(void)
-{
-	struct clock_event_device *evt = &__get_cpu_var(percpu_clockevent);
-	evt->event_handler(evt);
-}
-
 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
-static void smp_timer_broadcast(const struct cpumask *mask)
+void tick_broadcast(const struct cpumask *mask)
 {
 	smp_cross_call(mask, IPI_TIMER);
 }
-#else
-#define smp_timer_broadcast	NULL
-#endif
-
-static void broadcast_timer_set_mode(enum clock_event_mode mode,
-	struct clock_event_device *evt)
-{
-}
-
-static void __cpuinit broadcast_timer_setup(struct clock_event_device *evt)
-{
-	evt->name	= "dummy_timer";
-	evt->features	= CLOCK_EVT_FEAT_ONESHOT |
-			  CLOCK_EVT_FEAT_PERIODIC |
-			  CLOCK_EVT_FEAT_DUMMY;
-	evt->rating	= 400;
-	evt->mult	= 1;
-	evt->set_mode	= broadcast_timer_set_mode;
-
-	clockevents_register_device(evt);
-}
-
-void __cpuinit percpu_timer_setup(void)
-{
-	unsigned int cpu = smp_processor_id();
-	struct clock_event_device *evt = &per_cpu(percpu_clockevent, cpu);
-
-	evt->cpumask = cpumask_of(cpu);
-	evt->broadcast = smp_timer_broadcast;
-
-	if (local_timer_setup(evt))
-		broadcast_timer_setup(evt);
-}
-
-#ifdef CONFIG_HOTPLUG_CPU
-/*
- * The generic clock events code purposely does not stop the local timer
- * on CPU_DEAD/CPU_DEAD_FROZEN hotplug events, so we have to do it
- * manually here.
- */
-static void percpu_timer_stop(void)
-{
-	unsigned int cpu = smp_processor_id();
-	struct clock_event_device *evt = &per_cpu(percpu_clockevent, cpu);
-
-	local_timer_stop(evt);
-}
 #endif
 
 static DEFINE_RAW_SPINLOCK(stop_lock);
@@ -506,14 +526,23 @@ static void ipi_cpu_stop(unsigned int cpu)
 	local_fiq_disable();
 	local_irq_disable();
 
-#ifdef CONFIG_HOTPLUG_CPU
-	platform_cpu_kill(cpu);
-#endif
-
 	while (1)
 		cpu_relax();
 }
 
+static DEFINE_PER_CPU(struct completion *, cpu_completion);
+
+int register_ipi_completion(struct completion *completion, int cpu)
+{
+	per_cpu(cpu_completion, cpu) = completion;
+	return IPI_COMPLETION;
+}
+
+static void ipi_complete(unsigned int cpu)
+{
+	complete(per_cpu(cpu_completion, cpu));
+}
+
 /*
  * Main handler for inter-processor interrupts
  */
@@ -527,15 +556,20 @@ void handle_IPI(int ipinr, struct pt_regs *regs)
 	unsigned int cpu = smp_processor_id();
 	struct pt_regs *old_regs = set_irq_regs(regs);
 
-	if (ipinr >= IPI_TIMER && ipinr < IPI_TIMER + NR_IPI)
-		__inc_irq_stat(cpu, ipi_irqs[ipinr - IPI_TIMER]);
+	if (ipinr < NR_IPI)
+		__inc_irq_stat(cpu, ipi_irqs[ipinr]);
 
 	switch (ipinr) {
+	case IPI_WAKEUP:
+		break;
+
+#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
 	case IPI_TIMER:
 		irq_enter();
-		ipi_timer();
+		tick_receive_broadcast();
 		irq_exit();
 		break;
+#endif
 
 	case IPI_RESCHEDULE:
 		scheduler_ipi();
@@ -559,6 +593,20 @@ void handle_IPI(int ipinr, struct pt_regs *regs)
 		irq_exit();
 		break;
 
+#ifdef CONFIG_IRQ_WORK
+	case IPI_IRQ_WORK:
+		irq_enter();
+		irq_work_run();
+		irq_exit();
+		break;
+#endif
+
+	case IPI_COMPLETION:
+		irq_enter();
+		ipi_complete(cpu);
+		irq_exit();
+		break;
+
 	default:
 		printk(KERN_CRIT "CPU%u: Unknown IPI message 0x%x\n",
 		       cpu, ipinr);
@@ -575,13 +623,12 @@ void smp_send_reschedule(int cpu)
 void smp_send_stop(void)
 {
 	unsigned long timeout;
+	struct cpumask mask;
 
-	if (num_online_cpus() > 1) {
-		cpumask_t mask = cpu_online_map;
-		cpu_clear(smp_processor_id(), mask);
-
+	cpumask_copy(&mask, cpu_online_mask);
+	cpumask_clear_cpu(smp_processor_id(), &mask);
+	if (!cpumask_empty(&mask))
 		smp_cross_call(&mask, IPI_CPU_STOP);
-	}
 
 	/* Wait up to one second for other CPUs to stop */
 	timeout = USEC_PER_SEC;
@@ -599,3 +646,55 @@ int setup_profiling_timer(unsigned int multiplier)
 {
 	return -EINVAL;
 }
+
+#ifdef CONFIG_CPU_FREQ
+
+static DEFINE_PER_CPU(unsigned long, l_p_j_ref);
+static DEFINE_PER_CPU(unsigned long, l_p_j_ref_freq);
+static unsigned long global_l_p_j_ref;
+static unsigned long global_l_p_j_ref_freq;
+
+static int cpufreq_callback(struct notifier_block *nb,
+					unsigned long val, void *data)
+{
+	struct cpufreq_freqs *freq = data;
+	int cpu = freq->cpu;
+
+	if (freq->flags & CPUFREQ_CONST_LOOPS)
+		return NOTIFY_OK;
+
+	if (!per_cpu(l_p_j_ref, cpu)) {
+		per_cpu(l_p_j_ref, cpu) =
+			per_cpu(cpu_data, cpu).loops_per_jiffy;
+		per_cpu(l_p_j_ref_freq, cpu) = freq->old;
+		if (!global_l_p_j_ref) {
+			global_l_p_j_ref = loops_per_jiffy;
+			global_l_p_j_ref_freq = freq->old;
+		}
+	}
+
+	if ((val == CPUFREQ_PRECHANGE  && freq->old < freq->new) ||
+	    (val == CPUFREQ_POSTCHANGE && freq->old > freq->new)) {
+		loops_per_jiffy = cpufreq_scale(global_l_p_j_ref,
+						global_l_p_j_ref_freq,
+						freq->new);
+		per_cpu(cpu_data, cpu).loops_per_jiffy =
+			cpufreq_scale(per_cpu(l_p_j_ref, cpu),
+					per_cpu(l_p_j_ref_freq, cpu),
+					freq->new);
+	}
+	return NOTIFY_OK;
+}
+
+static struct notifier_block cpufreq_notifier = {
+	.notifier_call  = cpufreq_callback,
+};
+
+static int __init register_cpufreq_notifier(void)
+{
+	return cpufreq_register_notifier(&cpufreq_notifier,
+						CPUFREQ_TRANSITION_NOTIFIER);
+}
+core_initcall(register_cpufreq_notifier);
+
+#endif