Merge back cpufreq material for 3.19-rc1.

Documentation/cpu-freq/intel-pstate.txt

@@ -1,17 +1,28 @@
 Intel P-state driver
 --------------------
 
-This driver implements a scaling driver with an internal governor for
-Intel Core processors.  The driver follows the same model as the
-Transmeta scaling driver (longrun.c) and implements the setpolicy()
-instead of target().  Scaling drivers that implement setpolicy() are
-assumed to implement internal governors by the cpufreq core. All the
-logic for selecting the current P state is contained within the
-driver; no external governor is used by the cpufreq core.
-
-Intel SandyBridge+ processors are supported.
-
-New sysfs files for controlling P state selection have been added to
+This driver provides an interface to control the P state selection for
+SandyBridge+ Intel processors.  The driver can operate two different
+modes based on the processor model legacy and Hardware P state (HWP)
+mode.
+
+In legacy mode the driver implements a scaling driver with an internal
+governor for Intel Core processors.  The driver follows the same model
+as the Transmeta scaling driver (longrun.c) and implements the
+setpolicy() instead of target().  Scaling drivers that implement
+setpolicy() are assumed to implement internal governors by the cpufreq
+core. All the logic for selecting the current P state is contained
+within the driver; no external governor is used by the cpufreq core.
+
+In HWP mode P state selection is implemented in the processor
+itself. The driver provides the interfaces between the cpufreq core and
+the processor to control P state selection based on user preferences
+and reporting frequency to the cpufreq core.  In this mode the
+internal governor code is disabled.
+
+In addtion to the interfaces provided by the cpufreq core for
+controlling frequency the driver provides sysfs files for
+controlling P state selection. These files have been added to
 /sys/devices/system/cpu/intel_pstate/
 
       max_perf_pct: limits the maximum P state that will be requested by
@@ -33,7 +44,9 @@ frequency is fiction for Intel Core processors. Even if the scaling
 driver selects a single P state the actual frequency the processor
 will run at is selected by the processor itself.
 
-New debugfs files have also been added to /sys/kernel/debug/pstate_snb/
+For legacy mode debugfs files have also been added to allow tuning of
+the internal governor algorythm. These files are located at
+/sys/kernel/debug/pstate_snb/ These files are NOT present in HWP mode.
 
       deadband
       d_gain_pct

Documentation/kernel-parameters.txt

@@ -1446,6 +1446,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 		       disable
 		         Do not enable intel_pstate as the default
 		         scaling driver for the supported processors
+		       no_hwp
+		         Do not enable hardware P state control (HWP)
+			 if available.
 
 	intremap=	[X86-64, Intel-IOMMU]
 			on	enable Interrupt Remapping (default)

arch/x86/include/asm/cpufeature.h

@@ -189,6 +189,11 @@
 #define X86_FEATURE_DTHERM	( 7*32+ 7) /* Digital Thermal Sensor */
 #define X86_FEATURE_HW_PSTATE	( 7*32+ 8) /* AMD HW-PState */
 #define X86_FEATURE_PROC_FEEDBACK ( 7*32+ 9) /* AMD ProcFeedbackInterface */
+#define X86_FEATURE_HWP		( 7*32+ 10) /* "hwp" Intel HWP */
+#define X86_FEATURE_HWP_NOITFY	( 7*32+ 11) /* Intel HWP_NOTIFY */
+#define X86_FEATURE_HWP_ACT_WINDOW ( 7*32+ 12) /* Intel HWP_ACT_WINDOW */
+#define X86_FEATURE_HWP_EPP	( 7*32+13) /* Intel HWP_EPP */
+#define X86_FEATURE_HWP_PKG_REQ ( 7*32+14) /* Intel HWP_PKG_REQ */
 
 /* Virtualization flags: Linux defined, word 8 */
 #define X86_FEATURE_TPR_SHADOW  ( 8*32+ 0) /* Intel TPR Shadow */

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

@@ -152,6 +152,45 @@
 #define MSR_CC6_DEMOTION_POLICY_CONFIG	0x00000668
 #define MSR_MC6_DEMOTION_POLICY_CONFIG	0x00000669
 
+/* Hardware P state interface */
+#define MSR_PPERF			0x0000064e
+#define MSR_PERF_LIMIT_REASONS		0x0000064f
+#define MSR_PM_ENABLE			0x00000770
+#define MSR_HWP_CAPABILITIES		0x00000771
+#define MSR_HWP_REQUEST_PKG		0x00000772
+#define MSR_HWP_INTERRUPT		0x00000773
+#define MSR_HWP_REQUEST 		0x00000774
+#define MSR_HWP_STATUS			0x00000777
+
+/* CPUID.6.EAX */
+#define HWP_BASE_BIT			(1<<7)
+#define HWP_NOTIFICATIONS_BIT		(1<<8)
+#define HWP_ACTIVITY_WINDOW_BIT		(1<<9)
+#define HWP_ENERGY_PERF_PREFERENCE_BIT	(1<<10)
+#define HWP_PACKAGE_LEVEL_REQUEST_BIT	(1<<11)
+
+/* IA32_HWP_CAPABILITIES */
+#define HWP_HIGHEST_PERF(x)		(x & 0xff)
+#define HWP_GUARANTEED_PERF(x)		((x & (0xff << 8)) >>8)
+#define HWP_MOSTEFFICIENT_PERF(x)	((x & (0xff << 16)) >>16)
+#define HWP_LOWEST_PERF(x)		((x & (0xff << 24)) >>24)
+
+/* IA32_HWP_REQUEST */
+#define HWP_MIN_PERF(x) 		(x & 0xff)
+#define HWP_MAX_PERF(x) 		((x & 0xff) << 8)
+#define HWP_DESIRED_PERF(x)		((x & 0xff) << 16)
+#define HWP_ENERGY_PERF_PREFERENCE(x)	((x & 0xff) << 24)
+#define HWP_ACTIVITY_WINDOW(x)		((x & 0xff3) << 32)
+#define HWP_PACKAGE_CONTROL(x)		((x & 0x1) << 42)
+
+/* IA32_HWP_STATUS */
+#define HWP_GUARANTEED_CHANGE(x)	(x & 0x1)
+#define HWP_EXCURSION_TO_MINIMUM(x)	(x & 0x4)
+
+/* IA32_HWP_INTERRUPT */
+#define HWP_CHANGE_TO_GUARANTEED_INT(x)	(x & 0x1)
+#define HWP_EXCURSION_TO_MINIMUM_INT(x)	(x & 0x2)
+
 #define MSR_AMD64_MC0_MASK		0xc0010044
 
 #define MSR_IA32_MCx_CTL(x)		(MSR_IA32_MC0_CTL + 4*(x))
@@ -345,6 +384,8 @@
 
 #define MSR_IA32_TEMPERATURE_TARGET	0x000001a2
 
+#define MSR_MISC_PWR_MGMT		0x000001aa
+
 #define MSR_IA32_ENERGY_PERF_BIAS	0x000001b0
 #define ENERGY_PERF_BIAS_PERFORMANCE	0
 #define ENERGY_PERF_BIAS_NORMAL		6

arch/x86/kernel/cpu/scattered.c

@@ -36,6 +36,11 @@ void init_scattered_cpuid_features(struct cpuinfo_x86 *c)
 		{ X86_FEATURE_ARAT,		CR_EAX, 2, 0x00000006, 0 },
 		{ X86_FEATURE_PLN,		CR_EAX, 4, 0x00000006, 0 },
 		{ X86_FEATURE_PTS,		CR_EAX, 6, 0x00000006, 0 },
+		{ X86_FEATURE_HWP,		CR_EAX, 7, 0x00000006, 0 },
+		{ X86_FEATURE_HWP_NOITFY,	CR_EAX, 8, 0x00000006, 0 },
+		{ X86_FEATURE_HWP_ACT_WINDOW,	CR_EAX, 9, 0x00000006, 0 },
+		{ X86_FEATURE_HWP_EPP,		CR_EAX,10, 0x00000006, 0 },
+		{ X86_FEATURE_HWP_PKG_REQ,	CR_EAX,11, 0x00000006, 0 },
 		{ X86_FEATURE_APERFMPERF,	CR_ECX, 0, 0x00000006, 0 },
 		{ X86_FEATURE_EPB,		CR_ECX, 3, 0x00000006, 0 },
 		{ X86_FEATURE_HW_PSTATE,	CR_EDX, 7, 0x80000007, 0 },

drivers/cpufreq/Kconfig

@@ -63,7 +63,6 @@ config CPU_FREQ_DEFAULT_GOV_PERFORMANCE
 
 config CPU_FREQ_DEFAULT_GOV_POWERSAVE
 	bool "powersave"
-	depends on EXPERT
 	select CPU_FREQ_GOV_POWERSAVE
 	help
 	  Use the CPUFreq governor 'powersave' as default. This sets
@@ -250,6 +249,16 @@ config LOONGSON2_CPUFREQ
 
 	  If in doubt, say N.
 
+config LOONGSON1_CPUFREQ
+	tristate "Loongson1 CPUFreq Driver"
+	help
+	  This option adds a CPUFreq driver for loongson1 processors which
+	  support software configurable cpu frequency.
+
+	  For details, take a look at <file:Documentation/cpu-freq/>.
+
+	  If in doubt, say N.
+
 endmenu
 
 menu "PowerPC CPU frequency scaling drivers"

drivers/cpufreq/Makefile

@@ -98,6 +98,7 @@ obj-$(CONFIG_CRIS_MACH_ARTPEC3)		+= cris-artpec3-cpufreq.o
 obj-$(CONFIG_ETRAXFS)			+= cris-etraxfs-cpufreq.o
 obj-$(CONFIG_IA64_ACPI_CPUFREQ)		+= ia64-acpi-cpufreq.o
 obj-$(CONFIG_LOONGSON2_CPUFREQ)		+= loongson2_cpufreq.o
+obj-$(CONFIG_LOONGSON1_CPUFREQ)		+= ls1x-cpufreq.o
 obj-$(CONFIG_SH_CPU_FREQ)		+= sh-cpufreq.o
 obj-$(CONFIG_SPARC_US2E_CPUFREQ)	+= sparc-us2e-cpufreq.o
 obj-$(CONFIG_SPARC_US3_CPUFREQ)		+= sparc-us3-cpufreq.o

drivers/cpufreq/cpufreq-dt.c

@@ -58,6 +58,8 @@ static int set_target(struct cpufreq_policy *policy, unsigned int index)
 	old_freq = clk_get_rate(cpu_clk) / 1000;
 
 	if (!IS_ERR(cpu_reg)) {
+		unsigned long opp_freq;
+
 		rcu_read_lock();
 		opp = dev_pm_opp_find_freq_ceil(cpu_dev, &freq_Hz);
 		if (IS_ERR(opp)) {
@@ -67,13 +69,16 @@ static int set_target(struct cpufreq_policy *policy, unsigned int index)
 			return PTR_ERR(opp);
 		}
 		volt = dev_pm_opp_get_voltage(opp);
+		opp_freq = dev_pm_opp_get_freq(opp);
 		rcu_read_unlock();
 		tol = volt * priv->voltage_tolerance / 100;
 		volt_old = regulator_get_voltage(cpu_reg);
+		dev_dbg(cpu_dev, "Found OPP: %ld kHz, %ld uV\n",
+			opp_freq / 1000, volt);
 	}
 
 	dev_dbg(cpu_dev, "%u MHz, %ld mV --> %u MHz, %ld mV\n",
-		old_freq / 1000, volt_old ? volt_old / 1000 : -1,
+		old_freq / 1000, (volt_old > 0) ? volt_old / 1000 : -1,
 		new_freq / 1000, volt ? volt / 1000 : -1);
 
 	/* scaling up?  scale voltage before frequency */
@@ -89,7 +94,7 @@ static int set_target(struct cpufreq_policy *policy, unsigned int index)
 	ret = clk_set_rate(cpu_clk, freq_exact);
 	if (ret) {
 		dev_err(cpu_dev, "failed to set clock rate: %d\n", ret);
-		if (!IS_ERR(cpu_reg))
+		if (!IS_ERR(cpu_reg) && volt_old > 0)
 			regulator_set_voltage_tol(cpu_reg, volt_old, tol);
 		return ret;
 	}

drivers/cpufreq/cpufreq.c

@@ -535,7 +535,7 @@ static int cpufreq_set_policy(struct cpufreq_policy *policy,
 static ssize_t store_##file_name					\
 (struct cpufreq_policy *policy, const char *buf, size_t count)		\
 {									\
-	int ret;							\
+	int ret, temp;							\
 	struct cpufreq_policy new_policy;				\
 									\
 	ret = cpufreq_get_policy(&new_policy, policy->cpu);		\
@@ -546,8 +546,10 @@ static ssize_t store_##file_name					\
 	if (ret != 1)							\
 		return -EINVAL;						\
 									\
+	temp = new_policy.object;					\
 	ret = cpufreq_set_policy(policy, &new_policy);		\
-	policy->user_policy.object = policy->object;			\
+	if (!ret)							\
+		policy->user_policy.object = temp;			\
 									\
 	return ret ? ret : count;					\
 }