ACPI: cpufreq: Switch to QoS requests instead of cpufreq notifier

The cpufreq core now takes the min/max frequency constraints via QoS
requests and the CPUFREQ_ADJUST notifier shall get removed later on.

Switch over to using the QoS request for maximum frequency constraint
for acpi driver.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 38 insertions, 62 deletions

diff --git a/drivers/acpi/processor_perflib.c b/drivers/acpi/processor_perflib.c
index ee87cb6f6e59..2261713d1aec 100644
--- a/drivers/acpi/processor_perflib.c
+++ b/drivers/acpi/processor_perflib.c
@@ -50,57 +50,13 @@ module_param(ignore_ppc, int, 0644);
 MODULE_PARM_DESC(ignore_ppc, "If the frequency of your machine gets wrongly" \
 		 "limited by BIOS, this should help");
 
-#define PPC_REGISTERED   1
-#define PPC_IN_USE       2
-
-static int acpi_processor_ppc_status;
-
-static int acpi_processor_ppc_notifier(struct notifier_block *nb,
-				       unsigned long event, void *data)
-{
-	struct cpufreq_policy *policy = data;
-	struct acpi_processor *pr;
-	unsigned int ppc = 0;
-
-	if (ignore_ppc < 0)
-		ignore_ppc = 0;
-
-	if (ignore_ppc)
-		return 0;
-
-	if (event != CPUFREQ_ADJUST)
-		return 0;
-
-	mutex_lock(&performance_mutex);
-
-	pr = per_cpu(processors, policy->cpu);
-	if (!pr || !pr->performance)
-		goto out;
-
-	ppc = (unsigned int)pr->performance_platform_limit;
-
-	if (ppc >= pr->performance->state_count)
-		goto out;
-
-	cpufreq_verify_within_limits(policy, 0,
-				     pr->performance->states[ppc].
-				     core_frequency * 1000);
-
-      out:
-	mutex_unlock(&performance_mutex);
-
-	return 0;
-}
-
-static struct notifier_block acpi_ppc_notifier_block = {
-	.notifier_call = acpi_processor_ppc_notifier,
-};
+static bool acpi_processor_ppc_in_use;
 
 static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
 {
 	acpi_status status = 0;
 	unsigned long long ppc = 0;
-
+	int ret;
 
 	if (!pr)
 		return -EINVAL;
@@ -112,7 +68,7 @@ static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
 	status = acpi_evaluate_integer(pr->handle, "_PPC", NULL, &ppc);
 
 	if (status != AE_NOT_FOUND)
-		acpi_processor_ppc_status |= PPC_IN_USE;
+		acpi_processor_ppc_in_use = true;
 
 	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
 		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PPC"));
@@ -124,6 +80,17 @@ static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
 
 	pr->performance_platform_limit = (int)ppc;
 
+	if (ppc >= pr->performance->state_count ||
+	    unlikely(!dev_pm_qos_request_active(&pr->perflib_req)))
+		return 0;
+
+	ret = dev_pm_qos_update_request(&pr->perflib_req,
+			pr->performance->states[ppc].core_frequency * 1000);
+	if (ret < 0) {
+		pr_warn("Failed to update perflib freq constraint: CPU%d (%d)\n",
+			pr->id, ret);
+	}
+
 	return 0;
 }
 
@@ -184,23 +151,32 @@ int acpi_processor_get_bios_limit(int cpu, unsigned int *limit)
 }
 EXPORT_SYMBOL(acpi_processor_get_bios_limit);
 
-void acpi_processor_ppc_init(void)
+void acpi_processor_ignore_ppc_init(void)
 {
-	if (!cpufreq_register_notifier
-	    (&acpi_ppc_notifier_block, CPUFREQ_POLICY_NOTIFIER))
-		acpi_processor_ppc_status |= PPC_REGISTERED;
-	else
-		printk(KERN_DEBUG
-		       "Warning: Processor Platform Limit not supported.\n");
+	if (ignore_ppc < 0)
+		ignore_ppc = 0;
+}
+
+void acpi_processor_ppc_init(int cpu)
+{
+	struct acpi_processor *pr = per_cpu(processors, cpu);
+	int ret;
+
+	ret = dev_pm_qos_add_request(get_cpu_device(cpu),
+				     &pr->perflib_req, DEV_PM_QOS_MAX_FREQUENCY,
+				     INT_MAX);
+	if (ret < 0) {
+		pr_err("Failed to add freq constraint for CPU%d (%d)\n", cpu,
+		       ret);
+		return;
+	}
 }
 
-void acpi_processor_ppc_exit(void)
+void acpi_processor_ppc_exit(int cpu)
 {
-	if (acpi_processor_ppc_status & PPC_REGISTERED)
-		cpufreq_unregister_notifier(&acpi_ppc_notifier_block,
-					    CPUFREQ_POLICY_NOTIFIER);
+	struct acpi_processor *pr = per_cpu(processors, cpu);
 
-	acpi_processor_ppc_status &= ~PPC_REGISTERED;
+	dev_pm_qos_remove_request(&pr->perflib_req);
 }
 
 static int acpi_processor_get_performance_control(struct acpi_processor *pr)
@@ -477,7 +453,7 @@ int acpi_processor_notify_smm(struct module *calling_module)
 	static int is_done = 0;
 	int result;
 
-	if (!(acpi_processor_ppc_status & PPC_REGISTERED))
+	if (!acpi_processor_cpufreq_init)
 		return -EBUSY;
 
 	if (!try_module_get(calling_module))
@@ -513,7 +489,7 @@ int acpi_processor_notify_smm(struct module *calling_module)
 	 * we can allow the cpufreq driver to be rmmod'ed. */
 	is_done = 1;
 
-	if (!(acpi_processor_ppc_status & PPC_IN_USE))
+	if (!acpi_processor_ppc_in_use)
 		module_put(calling_module);
 
 	return 0;
@@ -742,7 +718,7 @@ acpi_processor_register_performance(struct acpi_processor_performance
 {
 	struct acpi_processor *pr;
 
-	if (!(acpi_processor_ppc_status & PPC_REGISTERED))
+	if (!acpi_processor_cpufreq_init)
 		return -EINVAL;
 
 	mutex_lock(&performance_mutex);