Merge back cpufreq material for v5.9.

Author: rafaeljw

Documentation/admin-guide/kernel-parameters.txt

@@ -703,6 +703,11 @@
 	cpufreq.off=1	[CPU_FREQ]
 			disable the cpufreq sub-system
 
+	cpufreq.default_governor=
+			[CPU_FREQ] Name of the default cpufreq governor or
+			policy to use. This governor must be registered in the
+			kernel before the cpufreq driver probes.
+
 	cpu_init_udelay=N
 			[X86] Delay for N microsec between assert and de-assert
 			of APIC INIT to start processors.  This delay occurs

Documentation/admin-guide/pm/cpufreq.rst

@@ -147,9 +147,9 @@ CPUs in it.
 
 The next major initialization step for a new policy object is to attach a
 scaling governor to it (to begin with, that is the default scaling governor
-determined by the kernel configuration, but it may be changed later
-via ``sysfs``).  First, a pointer to the new policy object is passed to the
-governor's ``->init()`` callback which is expected to initialize all of the
+determined by the kernel command line or configuration, but it may be changed
+later via ``sysfs``).  First, a pointer to the new policy object is passed to
+the governor's ``->init()`` callback which is expected to initialize all of the
 data structures necessary to handle the given policy and, possibly, to add
 a governor ``sysfs`` interface to it.  Next, the governor is started by
 invoking its ``->start()`` callback.

Documentation/admin-guide/pm/intel_pstate.rst

@@ -431,6 +431,17 @@ argument is passed to the kernel in the command line.
 	supported in the current configuration, writes to this attribute will
 	fail with an appropriate error.
 
+``energy_efficiency``
+	This attribute is only present on platforms, which have CPUs matching
+	Kaby Lake or Coffee Lake desktop CPU model. By default
+	energy efficiency optimizations are disabled on these CPU models in HWP
+	mode by this driver. Enabling energy efficiency may limit maximum
+	operating frequency in both HWP and non HWP mode. In non HWP mode,
+	optimizations are done only in the turbo frequency range. In HWP mode,
+	optimizations are done in the entire frequency range. Setting this
+	attribute to "1" enables energy efficiency optimizations and setting
+	to "0" disables energy efficiency optimizations.
+
 Interpretation of Policy Attributes
 -----------------------------------
 
@@ -554,7 +565,11 @@ somewhere between the two extremes:
 Strings written to the ``energy_performance_preference`` attribute are
 internally translated to integer values written to the processor's
 Energy-Performance Preference (EPP) knob (if supported) or its
-Energy-Performance Bias (EPB) knob.
+Energy-Performance Bias (EPB) knob. It is also possible to write a positive
+integer value between 0 to 255, if the EPP feature is present. If the EPP
+feature is not present, writing integer value to this attribute is not
+supported. In this case, user can use
+ "/sys/devices/system/cpu/cpu*/power/energy_perf_bias" interface.
 
 [Note that tasks may by migrated from one CPU to another by the scheduler's
 load-balancing algorithm and if different energy vs performance hints are

arch/powerpc/platforms/cell/cpufreq_spudemand.c

@@ -126,30 +126,8 @@ static struct cpufreq_governor spu_governor = {
 	.stop = spu_gov_stop,
 	.owner = THIS_MODULE,
 };
-
-/*
- * module init and destoy
- */
-
-static int __init spu_gov_init(void)
-{
-	int ret;
-
-	ret = cpufreq_register_governor(&spu_governor);
-	if (ret)
-		printk(KERN_ERR "registration of governor failed\n");
-	return ret;
-}
-
-static void __exit spu_gov_exit(void)
-{
-	cpufreq_unregister_governor(&spu_governor);
-}
-
-
-module_init(spu_gov_init);
-module_exit(spu_gov_exit);
+cpufreq_governor_init(spu_governor);
+cpufreq_governor_exit(spu_governor);
 
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Christian Krafft <krafft@de.ibm.com>");
-

arch/x86/include/asm/msr-index.h

@@ -149,6 +149,10 @@
 
 #define MSR_LBR_SELECT			0x000001c8
 #define MSR_LBR_TOS			0x000001c9
+
+#define MSR_IA32_POWER_CTL		0x000001fc
+#define MSR_IA32_POWER_CTL_BIT_EE	19
+
 #define MSR_LBR_NHM_FROM		0x00000680
 #define MSR_LBR_NHM_TO			0x000006c0
 #define MSR_LBR_CORE_FROM		0x00000040
@@ -253,8 +257,6 @@
 
 #define MSR_PEBS_FRONTEND		0x000003f7
 
-#define MSR_IA32_POWER_CTL		0x000001fc
-
 #define MSR_IA32_MC0_CTL		0x00000400
 #define MSR_IA32_MC0_STATUS		0x00000401
 #define MSR_IA32_MC0_ADDR		0x00000402

drivers/cpufreq/acpi-cpufreq.c

@@ -244,7 +244,7 @@ static unsigned extract_freq(struct cpufreq_policy *policy, u32 val)
 
 static u32 cpu_freq_read_intel(struct acpi_pct_register *not_used)
 {
-	u32 val, dummy;
+	u32 val, dummy __always_unused;
 
 	rdmsr(MSR_IA32_PERF_CTL, val, dummy);
 	return val;
@@ -261,7 +261,7 @@ static void cpu_freq_write_intel(struct acpi_pct_register *not_used, u32 val)
 
 static u32 cpu_freq_read_amd(struct acpi_pct_register *not_used)
 {
-	u32 val, dummy;
+	u32 val, dummy __always_unused;
 
 	rdmsr(MSR_AMD_PERF_CTL, val, dummy);
 	return val;
@@ -612,7 +612,7 @@ static const struct dmi_system_id sw_any_bug_dmi_table[] = {
 static int acpi_cpufreq_blacklist(struct cpuinfo_x86 *c)
 {
 	/* Intel Xeon Processor 7100 Series Specification Update
-	 * http://www.intel.com/Assets/PDF/specupdate/314554.pdf
+	 * https://www.intel.com/Assets/PDF/specupdate/314554.pdf
 	 * AL30: A Machine Check Exception (MCE) Occurring during an
 	 * Enhanced Intel SpeedStep Technology Ratio Change May Cause
 	 * Both Processor Cores to Lock Up. */
@@ -993,14 +993,14 @@ MODULE_PARM_DESC(acpi_pstate_strict,
 late_initcall(acpi_cpufreq_init);
 module_exit(acpi_cpufreq_exit);
 
-static const struct x86_cpu_id acpi_cpufreq_ids[] = {
+static const struct x86_cpu_id __maybe_unused acpi_cpufreq_ids[] = {
 	X86_MATCH_FEATURE(X86_FEATURE_ACPI, NULL),
 	X86_MATCH_FEATURE(X86_FEATURE_HW_PSTATE, NULL),
 	{}
 };
 MODULE_DEVICE_TABLE(x86cpu, acpi_cpufreq_ids);
 
-static const struct acpi_device_id processor_device_ids[] = {
+static const struct acpi_device_id __maybe_unused processor_device_ids[] = {
 	{ACPI_PROCESSOR_OBJECT_HID, },
 	{ACPI_PROCESSOR_DEVICE_HID, },
 	{},

drivers/cpufreq/amd_freq_sensitivity.c

@@ -144,7 +144,7 @@ static void __exit amd_freq_sensitivity_exit(void)
 }
 module_exit(amd_freq_sensitivity_exit);
 
-static const struct x86_cpu_id amd_freq_sensitivity_ids[] = {
+static const struct x86_cpu_id __maybe_unused amd_freq_sensitivity_ids[] = {
 	X86_MATCH_FEATURE(X86_FEATURE_PROC_FEEDBACK, NULL),
 	{}
 };