Merge branch 'pm-cpufreq'

* pm-cpufreq:
  cpufreq: s5pv210-cpufreq: fix wrong do_div() usage
  MAINTAINERS: update for intel P-state driver
  cpufreq: governor: Quit work-handlers early if governor is stopped
  intel_pstate: decrease number of "HWP enabled" messages
  cpufreq: arm_big_little: fix frequency check when bL switcher is active

5 files changed, 46 insertions, 26 deletions

diff --git a/MAINTAINERS b/MAINTAINERS
index caddb49b207d..08a1378c70ed 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -5440,7 +5440,8 @@ S:	Supported
 F:	drivers/idle/intel_idle.c
 
 INTEL PSTATE DRIVER
-M:	Kristen Carlson Accardi <kristen@linux.intel.com>
+M:	Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
+M:	Len Brown <lenb@kernel.org>
 L:	linux-pm@vger.kernel.org
 S:	Supported
 F:	drivers/cpufreq/intel_pstate.c
diff --git a/drivers/cpufreq/arm_big_little.c b/drivers/cpufreq/arm_big_little.c
index f1e42f8ce0fc..c5d256caa664 100644
--- a/drivers/cpufreq/arm_big_little.c
+++ b/drivers/cpufreq/arm_big_little.c
@@ -149,6 +149,19 @@ bL_cpufreq_set_rate(u32 cpu, u32 old_cluster, u32 new_cluster, u32 rate)
 			__func__, cpu, old_cluster, new_cluster, new_rate);
 
 	ret = clk_set_rate(clk[new_cluster], new_rate * 1000);
+	if (!ret) {
+		/*
+		 * FIXME: clk_set_rate hasn't returned an error here however it
+		 * may be that clk_change_rate failed due to hardware or
+		 * firmware issues and wasn't able to report that due to the
+		 * current design of the clk core layer. To work around this
+		 * problem we will read back the clock rate and check it is
+		 * correct. This needs to be removed once clk core is fixed.
+		 */
+		if (clk_get_rate(clk[new_cluster]) != new_rate * 1000)
+			ret = -EIO;
+	}
+
 	if (WARN_ON(ret)) {
 		pr_err("clk_set_rate failed: %d, new cluster: %d\n", ret,
 				new_cluster);
@@ -189,15 +202,6 @@ bL_cpufreq_set_rate(u32 cpu, u32 old_cluster, u32 new_cluster, u32 rate)
 		mutex_unlock(&cluster_lock[old_cluster]);
 	}
 
-	/*
-	 * FIXME: clk_set_rate has to handle the case where clk_change_rate
-	 * can fail due to hardware or firmware issues. Until the clk core
-	 * layer is fixed, we can check here. In most of the cases we will
-	 * be reading only the cached value anyway. This needs to  be removed
-	 * once clk core is fixed.
-	 */
-	if (bL_cpufreq_get_rate(cpu) != new_rate)
-		return -EIO;
 	return 0;
 }
 
diff --git a/drivers/cpufreq/cpufreq_governor.c b/drivers/cpufreq/cpufreq_governor.c
index 11258c4c1b17..b260576ddb12 100644
--- a/drivers/cpufreq/cpufreq_governor.c
+++ b/drivers/cpufreq/cpufreq_governor.c
@@ -171,10 +171,6 @@ void gov_queue_work(struct dbs_data *dbs_data, struct cpufreq_policy *policy,
 {
 	int i;
 
-	mutex_lock(&cpufreq_governor_lock);
-	if (!policy->governor_enabled)
-		goto out_unlock;
-
 	if (!all_cpus) {
 		/*
 		 * Use raw_smp_processor_id() to avoid preemptible warnings.
@@ -188,9 +184,6 @@ void gov_queue_work(struct dbs_data *dbs_data, struct cpufreq_policy *policy,
 		for_each_cpu(i, policy->cpus)
 			__gov_queue_work(i, dbs_data, delay);
 	}
-
-out_unlock:
-	mutex_unlock(&cpufreq_governor_lock);
 }
 EXPORT_SYMBOL_GPL(gov_queue_work);
 
@@ -229,13 +222,24 @@ static void dbs_timer(struct work_struct *work)
 	struct cpu_dbs_info *cdbs = container_of(work, struct cpu_dbs_info,
 						 dwork.work);
 	struct cpu_common_dbs_info *shared = cdbs->shared;
-	struct cpufreq_policy *policy = shared->policy;
-	struct dbs_data *dbs_data = policy->governor_data;
+	struct cpufreq_policy *policy;
+	struct dbs_data *dbs_data;
 	unsigned int sampling_rate, delay;
 	bool modify_all = true;
 
 	mutex_lock(&shared->timer_mutex);
 
+	policy = shared->policy;
+
+	/*
+	 * Governor might already be disabled and there is no point continuing
+	 * with the work-handler.
+	 */
+	if (!policy)
+		goto unlock;
+
+	dbs_data = policy->governor_data;
+
 	if (dbs_data->cdata->governor == GOV_CONSERVATIVE) {
 		struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
 
@@ -252,6 +256,7 @@ static void dbs_timer(struct work_struct *work)
 	delay = dbs_data->cdata->gov_dbs_timer(cdbs, dbs_data, modify_all);
 	gov_queue_work(dbs_data, policy, delay, modify_all);
 
+unlock:
 	mutex_unlock(&shared->timer_mutex);
 }
 
@@ -478,9 +483,17 @@ static int cpufreq_governor_stop(struct cpufreq_policy *policy,
 	if (!shared || !shared->policy)
 		return -EBUSY;
 
+	/*
+	 * Work-handler must see this updated, as it should not proceed any
+	 * further after governor is disabled. And so timer_mutex is taken while
+	 * updating this value.
+	 */
+	mutex_lock(&shared->timer_mutex);
+	shared->policy = NULL;
+	mutex_unlock(&shared->timer_mutex);
+
 	gov_cancel_work(dbs_data, policy);
 
-	shared->policy = NULL;
 	mutex_destroy(&shared->timer_mutex);
 	return 0;
 }
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index 93a3c635ea27..2e31d097def6 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -684,8 +684,6 @@ static void __init intel_pstate_sysfs_expose_params(void)
 
 static void intel_pstate_hwp_enable(struct cpudata *cpudata)
 {
-	pr_info("intel_pstate: HWP enabled\n");
-
 	wrmsrl_on_cpu(cpudata->cpu, MSR_PM_ENABLE, 0x1);
 }
 
@@ -1557,8 +1555,10 @@ static int __init intel_pstate_init(void)
 	if (!all_cpu_data)
 		return -ENOMEM;
 
-	if (static_cpu_has_safe(X86_FEATURE_HWP) && !no_hwp)
+	if (static_cpu_has_safe(X86_FEATURE_HWP) && !no_hwp) {
+		pr_info("intel_pstate: HWP enabled\n");
 		hwp_active++;
+	}
 
 	if (!hwp_active && hwp_only)
 		goto out;
@@ -1593,8 +1593,10 @@ static int __init intel_pstate_setup(char *str)
 
 	if (!strcmp(str, "disable"))
 		no_load = 1;
-	if (!strcmp(str, "no_hwp"))
+	if (!strcmp(str, "no_hwp")) {
+		pr_info("intel_pstate: HWP disabled\n");
 		no_hwp = 1;
+	}
 	if (!strcmp(str, "force"))
 		force_load = 1;
 	if (!strcmp(str, "hwp_only"))
diff --git a/drivers/cpufreq/s5pv210-cpufreq.c b/drivers/cpufreq/s5pv210-cpufreq.c
index 9e231f52150c..051a8a8224cd 100644
--- a/drivers/cpufreq/s5pv210-cpufreq.c
+++ b/drivers/cpufreq/s5pv210-cpufreq.c
@@ -212,11 +212,11 @@ static void s5pv210_set_refresh(enum s5pv210_dmc_port ch, unsigned long freq)
 	/* Find current DRAM frequency */
 	tmp = s5pv210_dram_conf[ch].freq;
 
-	do_div(tmp, freq);
+	tmp /= freq;
 
 	tmp1 = s5pv210_dram_conf[ch].refresh;
 
-	do_div(tmp1, tmp);
+	tmp1 /= tmp;
 
 	__raw_writel(tmp1, reg);
 }