[CPUFREQ] _PPC frequency change issues

BIOS might change frequency behind our back when BIOS changes allowed
frequencies via _PPC.  In this case cpufreq core got out of sync.
Ask driver for current freq and notify governors about a change

Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 0a6c4c8642e7..7a511479ae29 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1429,6 +1429,14 @@ int cpufreq_update_policy(unsigned int cpu)
         policy.policy = data->user_policy.policy;
         policy.governor = data->user_policy.governor;
 
+        /* BIOS might change freq behind our back
+          -> ask driver for current freq and notify governors about a change */
+        if (cpufreq_driver->get) {
+                policy.cur = cpufreq_driver->get(cpu);
+                if (data->cur != policy.cur)
+                        cpufreq_out_of_sync(cpu, data->cur, policy.cur);
+        }
+
         ret = __cpufreq_set_policy(data, &policy);
 
         mutex_unlock(&data->lock);