Merge tag 'pm-for-3.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael...

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / arch / arm / kernel / smp.c

diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index aa4ffe6e5ecfbd9a8feeedf1c002ca50861ae541..dea7a925c7e249375a86c9c943302a926c865433 100644 (file)
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -24,6 +24,7 @@
 #include <linux/percpu.h>
 #include <linux/clockchips.h>
 #include <linux/completion.h>
+#include <linux/cpufreq.h>
 
 #include <linux/atomic.h>
 #include <asm/smp.h>
@@ -650,3 +651,56 @@ 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) ||
+           (val == CPUFREQ_RESUMECHANGE || val == CPUFREQ_SUSPENDCHANGE)) {
+               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