[CPUFREQ] Also check whether the CPU frequency is out of sync once we get to cpufreq_...

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index bf9efc61c6bc997617dbbc5267cd8886b1d9a59d..c345cb233cf1eab27f6b19c419b4ef112519c32e 100644 (file)
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -38,7 +38,6 @@ static int __cpufreq_governor(struct cpufreq_policy *policy, unsigned int event)
 static void handle_update(void *data);
 static inline void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci);
 
-
 /**
  * Two notifier lists: the "policy" list is involved in the 
  * validation process for a new CPU frequency policy; the 
@@ -1049,6 +1048,22 @@ void cpufreq_notify_transition(struct cpufreq_freqs *freqs, unsigned int state)
        down_read(&cpufreq_notifier_rwsem);
        switch (state) {
        case CPUFREQ_PRECHANGE:
+               /* detect if the driver reported a value as "old frequency" which
+                * is not equal to what the cpufreq core thinks is "old frequency".
+                */
+               if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) {
+                       if ((likely(cpufreq_cpu_data[freqs->cpu]->cur)) &&
+                           (unlikely(freqs->old != cpufreq_cpu_data[freqs->cpu]->cur)))
+                       {
+                               if (cpufreq_driver->flags & CPUFREQ_PANIC_OUTOFSYNC)
+                                       panic("CPU Frequency is out of sync.");
+
+                               printk(KERN_WARNING "Warning: CPU frequency out of sync: "
+                                      "cpufreq and timing core thinks of %u, is %u kHz.\n", 
+                                      cpufreq_cpu_data[freqs->cpu]->cur, freqs->old);
+                               freqs->old = cpufreq_cpu_data[freqs->cpu]->cur;
+                       }
+               }
                notifier_call_chain(&cpufreq_transition_notifier_list, CPUFREQ_PRECHANGE, freqs);
                adjust_jiffies(CPUFREQ_PRECHANGE, freqs);
                break;