Merge git://git.kernel.org/pub/scm/linux/kernel/git/brodo/cpupowerutils

* git://git.kernel.org/pub/scm/linux/kernel/git/brodo/cpupowerutils:
  cpupower: use man(1) when calling "cpupower help subcommand"
  cpupower: make NLS truly optional
  cpupower: fix Makefile typo
  cpupower: Make monitor command -c/--cpu aware
  cpupower: Better detect offlined CPUs
  cpupower: Do not show an empty Idle_Stats monitor if no idle driver is available
  cpupower: mperf monitor - Use TSC to calculate max frequency if possible
  cpupower: avoid using symlinks

21 files changed, 308 insertions, 289 deletions

diff --git a/tools/power/cpupower/Makefile b/tools/power/cpupower/Makefile
index 94c2cf0a98b8..e8a03aceceb1 100644
--- a/tools/power/cpupower/Makefile
+++ b/tools/power/cpupower/Makefile
@@ -24,7 +24,7 @@
 
 # Set the following to `true' to make a unstripped, unoptimized
 # binary. Leave this set to `false' for production use.
-DEBUG ?=	false
+DEBUG ?=	true
 
 # make the build silent. Set this to something else to make it noisy again.
 V ?=		false
@@ -35,7 +35,7 @@ NLS ?=		true
 
 # Set the following to 'true' to build/install the
 # cpufreq-bench benchmarking tool
-CPUFRQ_BENCH ?= true
+CPUFREQ_BENCH ?= true
 
 # Prefix to the directories we're installing to
 DESTDIR ?=
@@ -137,9 +137,10 @@ CFLAGS +=	-pipe
 ifeq ($(strip $(NLS)),true)
 	INSTALL_NLS += install-gmo
 	COMPILE_NLS += create-gmo
+	CFLAGS += -DNLS
 endif
 
-ifeq ($(strip $(CPUFRQ_BENCH)),true)
+ifeq ($(strip $(CPUFREQ_BENCH)),true)
 	INSTALL_BENCH += install-bench
 	COMPILE_BENCH += compile-bench
 endif
diff --git a/tools/power/cpupower/debug/x86_64/Makefile b/tools/power/cpupower/debug/x86_64/Makefile
index dbf13998462a..3326217dd311 100644
--- a/tools/power/cpupower/debug/x86_64/Makefile
+++ b/tools/power/cpupower/debug/x86_64/Makefile
@@ -1,10 +1,10 @@
 default: all
 
-centrino-decode: centrino-decode.c
-	$(CC) $(CFLAGS) -o centrino-decode centrino-decode.c
+centrino-decode: ../i386/centrino-decode.c
+	$(CC) $(CFLAGS) -o $@ $<
 
-powernow-k8-decode: powernow-k8-decode.c
-	$(CC) $(CFLAGS) -o powernow-k8-decode powernow-k8-decode.c
+powernow-k8-decode: ../i386/powernow-k8-decode.c
+	$(CC) $(CFLAGS) -o $@ $<
 
 all: centrino-decode powernow-k8-decode
 
diff --git a/tools/power/cpupower/debug/x86_64/centrino-decode.c b/tools/power/cpupower/debug/x86_64/centrino-decode.c
deleted file mode 120000
index 26fb3f1d8fc7..000000000000
--- a/tools/power/cpupower/debug/x86_64/centrino-decode.c
+++ /dev/null
@@ -1 +0,0 @@
-../i386/centrino-decode.c
\ No newline at end of file
diff --git a/tools/power/cpupower/debug/x86_64/powernow-k8-decode.c b/tools/power/cpupower/debug/x86_64/powernow-k8-decode.c
deleted file mode 120000
index eb30c79cf9df..000000000000
--- a/tools/power/cpupower/debug/x86_64/powernow-k8-decode.c
+++ /dev/null
@@ -1 +0,0 @@
-../i386/powernow-k8-decode.c
\ No newline at end of file
diff --git a/tools/power/cpupower/man/cpupower-frequency-info.1 b/tools/power/cpupower/man/cpupower-frequency-info.1
index 3194811d58f5..bb60a8d1e45a 100644
--- a/tools/power/cpupower/man/cpupower-frequency-info.1
+++ b/tools/power/cpupower/man/cpupower-frequency-info.1
@@ -1,10 +1,10 @@
-.TH "cpufreq-info" "1" "0.1" "Mattia Dongili" ""
+.TH "cpupower-frequency-info" "1" "0.1" "Mattia Dongili" ""
 .SH "NAME"
 .LP 
-cpufreq\-info \- Utility to retrieve cpufreq kernel information
+cpupower frequency\-info \- Utility to retrieve cpufreq kernel information
 .SH "SYNTAX"
 .LP 
-cpufreq\-info [\fIoptions\fP]
+cpupower [ \-c cpulist ] frequency\-info [\fIoptions\fP]
 .SH "DESCRIPTION"
 .LP 
 A small tool which prints out cpufreq information helpful to developers and interested users.
diff --git a/tools/power/cpupower/man/cpupower-frequency-set.1 b/tools/power/cpupower/man/cpupower-frequency-set.1
index 26e3e13eee3b..685f469093ad 100644
--- a/tools/power/cpupower/man/cpupower-frequency-set.1
+++ b/tools/power/cpupower/man/cpupower-frequency-set.1
@@ -1,13 +1,13 @@
-.TH "cpufreq-set" "1" "0.1" "Mattia Dongili" ""
+.TH "cpupower-freqency-set" "1" "0.1" "Mattia Dongili" ""
 .SH "NAME"
 .LP 
-cpufreq\-set \- A small tool which allows to modify cpufreq settings.
+cpupower frequency\-set \- A small tool which allows to modify cpufreq settings.
 .SH "SYNTAX"
 .LP 
-cpufreq\-set [\fIoptions\fP]
+cpupower [ \-c cpu ] frequency\-set [\fIoptions\fP]
 .SH "DESCRIPTION"
 .LP 
-cpufreq\-set allows you to modify cpufreq settings without having to type e.g. "/sys/devices/system/cpu/cpu0/cpufreq/scaling_set_speed" all the time.
+cpupower frequency\-set allows you to modify cpufreq settings without having to type e.g. "/sys/devices/system/cpu/cpu0/cpufreq/scaling_set_speed" all the time.
 .SH "OPTIONS"
 .LP 
 .TP 
diff --git a/tools/power/cpupower/man/cpupower.1 b/tools/power/cpupower/man/cpupower.1
index 78c20feab85c..baf741d06e82 100644
--- a/tools/power/cpupower/man/cpupower.1
+++ b/tools/power/cpupower/man/cpupower.1
@@ -3,7 +3,7 @@
 cpupower \- Shows and sets processor power related values
 .SH SYNOPSIS
 .ft B
-.B cpupower [ \-c cpulist ] subcommand [ARGS]
+.B cpupower [ \-c cpulist ] <command> [ARGS]
 
 .B cpupower \-v|\-\-version
 
@@ -13,24 +13,24 @@ cpupower \- Shows and sets processor power related values
 \fBcpupower \fP is a collection of tools to examine and tune power saving
 related features of your processor.
 
-The manpages of the subcommands (cpupower\-<subcommand>(1)) provide detailed
+The manpages of the commands (cpupower\-<command>(1)) provide detailed
 descriptions of supported features. Run \fBcpupower help\fP to get an overview
-of supported subcommands.
+of supported commands.
 
 .SH Options
 .PP
 \-\-help, \-h
 .RS 4
-Shows supported subcommands and general usage.
+Shows supported commands and general usage.
 .RE
 .PP
 \-\-cpu cpulist,  \-c cpulist
 .RS 4
 Only show or set values for specific cores.
-This option is not supported by all subcommands, details can be found in the
-manpages of the subcommands.
+This option is not supported by all commands, details can be found in the
+manpages of the commands.
 
-Some subcommands access all cores (typically the *\-set commands), some only
+Some commands access all cores (typically the *\-set commands), some only
 the first core (typically the *\-info commands) by default.
 
 The syntax for <cpulist> is based on how the kernel exports CPU bitmasks via
diff --git a/tools/power/cpupower/utils/builtin.h b/tools/power/cpupower/utils/builtin.h
index c870ffba5219..c10496fbe3c6 100644
--- a/tools/power/cpupower/utils/builtin.h
+++ b/tools/power/cpupower/utils/builtin.h
@@ -8,11 +8,4 @@ extern int cmd_freq_info(int argc, const char **argv);
 extern int cmd_idle_info(int argc, const char **argv);
 extern int cmd_monitor(int argc, const char **argv);
 
-extern void set_help(void);
-extern void info_help(void);
-extern void freq_set_help(void);
-extern void freq_info_help(void);
-extern void idle_info_help(void);
-extern void monitor_help(void);
-
 #endif
diff --git a/tools/power/cpupower/utils/cpufreq-info.c b/tools/power/cpupower/utils/cpufreq-info.c
index 5a1d25f056b3..28953c9a7bd5 100644
--- a/tools/power/cpupower/utils/cpufreq-info.c
+++ b/tools/power/cpupower/utils/cpufreq-info.c
@@ -510,37 +510,6 @@ static int get_latency(unsigned int cpu, unsigned int human)
 	return 0;
 }
 
-void freq_info_help(void)
-{
-	printf(_("Usage: cpupower freqinfo [options]\n"));
-	printf(_("Options:\n"));
-	printf(_("  -e, --debug          Prints out debug information [default]\n"));
-	printf(_("  -f, --freq           Get frequency the CPU currently runs at, according\n"
-	       "                       to the cpufreq core *\n"));
-	printf(_("  -w, --hwfreq         Get frequency the CPU currently runs at, by reading\n"
-	       "                       it from hardware (only available to root) *\n"));
-	printf(_("  -l, --hwlimits       Determine the minimum and maximum CPU frequency allowed *\n"));
-	printf(_("  -d, --driver         Determines the used cpufreq kernel driver *\n"));
-	printf(_("  -p, --policy         Gets the currently used cpufreq policy *\n"));
-	printf(_("  -g, --governors      Determines available cpufreq governors *\n"));
-	printf(_("  -r, --related-cpus   Determines which CPUs run at the same hardware frequency *\n"));
-	printf(_("  -a, --affected-cpus  Determines which CPUs need to have their frequency\n"
-			"                       coordinated by software *\n"));
-	printf(_("  -s, --stats          Shows cpufreq statistics if available\n"));
-	printf(_("  -y, --latency        Determines the maximum latency on CPU frequency changes *\n"));
-	printf(_("  -b, --boost          Checks for turbo or boost modes  *\n"));
-	printf(_("  -o, --proc           Prints out information like provided by the /proc/cpufreq\n"
-	       "                       interface in 2.4. and early 2.6. kernels\n"));
-	printf(_("  -m, --human          human-readable output for the -f, -w, -s and -y parameters\n"));
-	printf(_("  -h, --help           Prints out this screen\n"));
-
-	printf("\n");
-	printf(_("If no argument is given, full output about\n"
-	       "cpufreq is printed which is useful e.g. for reporting bugs.\n\n"));
-	printf(_("By default info of CPU 0 is shown which can be overridden\n"
-		 "with the cpupower --cpu main command option.\n"));
-}
-
 static struct option info_opts[] = {
 	{ .name = "debug",	.has_arg = no_argument,		.flag = NULL,	.val = 'e'},
 	{ .name = "boost",	.has_arg = no_argument,		.flag = NULL,	.val = 'b'},
@@ -556,7 +525,6 @@ static struct option info_opts[] = {
 	{ .name = "latency",	.has_arg = no_argument,		.flag = NULL,	.val = 'y'},
 	{ .name = "proc",	.has_arg = no_argument,		.flag = NULL,	.val = 'o'},
 	{ .name = "human",	.has_arg = no_argument,		.flag = NULL,	.val = 'm'},
-	{ .name = "help",	.has_arg = no_argument,		.flag = NULL,	.val = 'h'},
 	{ },
 };
 
@@ -570,16 +538,12 @@ int cmd_freq_info(int argc, char **argv)
 	int output_param = 0;
 
 	do {
-		ret = getopt_long(argc, argv, "hoefwldpgrasmyb", info_opts, NULL);
+		ret = getopt_long(argc, argv, "oefwldpgrasmyb", info_opts, NULL);
 		switch (ret) {
 		case '?':
 			output_param = '?';
 			cont = 0;
 			break;
-		case 'h':
-			output_param = 'h';
-			cont = 0;
-			break;
 		case -1:
 			cont = 0;
 			break;
@@ -642,11 +606,7 @@ int cmd_freq_info(int argc, char **argv)
 		return -EINVAL;
 	case '?':
 		printf(_("invalid or unknown argument\n"));
-		freq_info_help();
 		return -EINVAL;
-	case 'h':
-		freq_info_help();
-		return EXIT_SUCCESS;
 	case 'o':
 		proc_cpufreq_output();
 		return EXIT_SUCCESS;
diff --git a/tools/power/cpupower/utils/cpufreq-set.c b/tools/power/cpupower/utils/cpufreq-set.c
index 5f783622bf31..dd1539eb8c63 100644
--- a/tools/power/cpupower/utils/cpufreq-set.c
+++ b/tools/power/cpupower/utils/cpufreq-set.c
@@ -20,34 +20,11 @@
 
 #define NORM_FREQ_LEN 32
 
-void freq_set_help(void)
-{
-	printf(_("Usage: cpupower frequency-set [options]\n"));
-	printf(_("Options:\n"));
-	printf(_("  -d FREQ, --min FREQ      new minimum CPU frequency the governor may select\n"));
-	printf(_("  -u FREQ, --max FREQ      new maximum CPU frequency the governor may select\n"));
-	printf(_("  -g GOV, --governor GOV   new cpufreq governor\n"));
-	printf(_("  -f FREQ, --freq FREQ     specific frequency to be set. Requires userspace\n"
-	       "                           governor to be available and loaded\n"));
-	printf(_("  -r, --related            Switches all hardware-related CPUs\n"));
-	printf(_("  -h, --help               Prints out this screen\n"));
-	printf("\n");
-	printf(_("Notes:\n"
-	       "1. Omitting the -c or --cpu argument is equivalent to setting it to \"all\"\n"));
-	printf(_("2. The -f FREQ, --freq FREQ parameter cannot be combined with any other parameter\n"
-	       "   except the -c CPU, --cpu CPU parameter\n"
-	       "3. FREQuencies can be passed in Hz, kHz (default), MHz, GHz, or THz\n"
-	       "   by postfixing the value with the wanted unit name, without any space\n"
-	       "   (FREQuency in kHz =^ Hz * 0.001 =^ MHz * 1000 =^ GHz * 1000000).\n"));
-
-}
-
 static struct option set_opts[] = {
 	{ .name = "min",	.has_arg = required_argument,	.flag = NULL,	.val = 'd'},
 	{ .name = "max",	.has_arg = required_argument,	.flag = NULL,	.val = 'u'},
 	{ .name = "governor",	.has_arg = required_argument,	.flag = NULL,	.val = 'g'},
 	{ .name = "freq",	.has_arg = required_argument,	.flag = NULL,	.val = 'f'},
-	{ .name = "help",	.has_arg = no_argument,		.flag = NULL,	.val = 'h'},
 	{ .name = "related",	.has_arg = no_argument,		.flag = NULL,	.val='r'},
 	{ },
 };
@@ -80,7 +57,6 @@ const struct freq_units def_units[] = {
 static void print_unknown_arg(void)
 {
 	printf(_("invalid or unknown argument\n"));
-	freq_set_help();
 }
 
 static unsigned long string_to_frequency(const char *str)
@@ -231,14 +207,11 @@ int cmd_freq_set(int argc, char **argv)
 
 	/* parameter parsing */
 	do {
-		ret = getopt_long(argc, argv, "d:u:g:f:hr", set_opts, NULL);
+		ret = getopt_long(argc, argv, "d:u:g:f:r", set_opts, NULL);
 		switch (ret) {
 		case '?':
 			print_unknown_arg();
 			return -EINVAL;
-		case 'h':
-			freq_set_help();
-			return 0;
 		case -1:
 			cont = 0;
 			break;
diff --git a/tools/power/cpupower/utils/cpuidle-info.c b/tools/power/cpupower/utils/cpuidle-info.c
index 70da3574f1e9..b028267c1376 100644
--- a/tools/power/cpupower/utils/cpuidle-info.c
+++ b/tools/power/cpupower/utils/cpuidle-info.c
@@ -139,30 +139,14 @@ static void proc_cpuidle_cpu_output(unsigned int cpu)
 	}
 }
 
-/* --freq / -f */
-
-void idle_info_help(void)
-{
-	printf(_ ("Usage: cpupower idleinfo [options]\n"));
-	printf(_ ("Options:\n"));
-	printf(_ ("  -s, --silent         Only show general C-state information\n"));
-	printf(_ ("  -o, --proc           Prints out information like provided by the /proc/acpi/processor/*/power\n"
-	       "                       interface in older kernels\n"));
-	printf(_ ("  -h, --help           Prints out this screen\n"));
-
-	printf("\n");
-}
-
 static struct option info_opts[] = {
 	{ .name = "silent",	.has_arg = no_argument,	.flag = NULL,	.val = 's'},
 	{ .name = "proc",	.has_arg = no_argument,	.flag = NULL,	.val = 'o'},
-	{ .name = "help",	.has_arg = no_argument,	.flag = NULL,	.val = 'h'},
 	{ },
 };
 
 static inline void cpuidle_exit(int fail)
 {
-	idle_info_help();
 	exit(EXIT_FAILURE);
 }
 
@@ -174,7 +158,7 @@ int cmd_idle_info(int argc, char **argv)
 	unsigned int cpu = 0;
 
 	do {
-		ret = getopt_long(argc, argv, "hos", info_opts, NULL);
+		ret = getopt_long(argc, argv, "os", info_opts, NULL);
 		if (ret == -1)
 			break;
 		switch (ret) {
@@ -182,10 +166,6 @@ int cmd_idle_info(int argc, char **argv)
 			output_param = '?';
 			cont = 0;
 			break;
-		case 'h':
-			output_param = 'h';
-			cont = 0;
-			break;
 		case 's':
 			verbose = 0;
 			break;
@@ -211,8 +191,6 @@ int cmd_idle_info(int argc, char **argv)
 	case '?':
 		printf(_("invalid or unknown argument\n"));
 		cpuidle_exit(EXIT_FAILURE);
-	case 'h':
-		cpuidle_exit(EXIT_SUCCESS);
 	}
 
 	/* Default is: show output of CPU 0 only */
diff --git a/tools/power/cpupower/utils/cpupower-info.c b/tools/power/cpupower/utils/cpupower-info.c
index 85253cb7600e..3f68632c28c7 100644
--- a/tools/power/cpupower/utils/cpupower-info.c
+++ b/tools/power/cpupower/utils/cpupower-info.c
@@ -16,31 +16,16 @@
 #include "helpers/helpers.h"
 #include "helpers/sysfs.h"
 
-void info_help(void)
-{
-	printf(_("Usage: cpupower info [ -b ] [ -m ] [ -s ]\n"));
-	printf(_("Options:\n"));
-	printf(_("  -b, --perf-bias    Gets CPU's power vs performance policy on some\n"
-	       "                           Intel models [0-15], see manpage for details\n"));
-	printf(_("  -m, --sched-mc     Gets the kernel's multi core scheduler policy.\n"));
-	printf(_("  -s, --sched-smt    Gets the kernel's thread sibling scheduler policy.\n"));
-	printf(_("  -h, --help               Prints out this screen\n"));
-	printf(_("\nPassing no option will show all info, by default only on core 0\n"));
-	printf("\n");
-}
-
 static struct option set_opts[] = {
 	{ .name = "perf-bias",	.has_arg = optional_argument,	.flag = NULL,	.val = 'b'},
 	{ .name = "sched-mc",	.has_arg = optional_argument,	.flag = NULL,	.val = 'm'},
 	{ .name = "sched-smt",	.has_arg = optional_argument,	.flag = NULL,	.val = 's'},
-	{ .name = "help",	.has_arg = no_argument,		.flag = NULL,	.val = 'h'},
 	{ },
 };
 
 static void print_wrong_arg_exit(void)
 {
 	printf(_("invalid or unknown argument\n"));
-	info_help();
 	exit(EXIT_FAILURE);
 }
 
@@ -64,11 +49,8 @@ int cmd_info(int argc, char **argv)
 	textdomain(PACKAGE);
 
 	/* parameter parsing */
-	while ((ret = getopt_long(argc, argv, "msbh", set_opts, NULL)) != -1) {
+	while ((ret = getopt_long(argc, argv, "msb", set_opts, NULL)) != -1) {
 		switch (ret) {
-		case 'h':
-			info_help();
-			return 0;
 		case 'b':
 			if (params.perf_bias)
 				print_wrong_arg_exit();
diff --git a/tools/power/cpupower/utils/cpupower-set.c b/tools/power/cpupower/utils/cpupower-set.c
index bc1b391e46f0..dc4de3762111 100644
--- a/tools/power/cpupower/utils/cpupower-set.c
+++ b/tools/power/cpupower/utils/cpupower-set.c
@@ -17,30 +17,16 @@
 #include "helpers/sysfs.h"
 #include "helpers/bitmask.h"
 
-void set_help(void)
-{
-	printf(_("Usage: cpupower set [ -b val ] [ -m val ] [ -s val ]\n"));
-	printf(_("Options:\n"));
-	printf(_("  -b, --perf-bias [VAL]    Sets CPU's power vs performance policy on some\n"
-	       "                           Intel models [0-15], see manpage for details\n"));
-	printf(_("  -m, --sched-mc  [VAL]    Sets the kernel's multi core scheduler policy.\n"));
-	printf(_("  -s, --sched-smt [VAL]    Sets the kernel's thread sibling scheduler policy.\n"));
-	printf(_("  -h, --help               Prints out this screen\n"));
-	printf("\n");
-}
-
 static struct option set_opts[] = {
 	{ .name = "perf-bias",	.has_arg = optional_argument,	.flag = NULL,	.val = 'b'},
 	{ .name = "sched-mc",	.has_arg = optional_argument,	.flag = NULL,	.val = 'm'},
 	{ .name = "sched-smt",	.has_arg = optional_argument,	.flag = NULL,	.val = 's'},
-	{ .name = "help",	.has_arg = no_argument,		.flag = NULL,	.val = 'h'},
 	{ },
 };
 
 static void print_wrong_arg_exit(void)
 {
 	printf(_("invalid or unknown argument\n"));
-	set_help();
 	exit(EXIT_FAILURE);
 }
 
@@ -66,12 +52,9 @@ int cmd_set(int argc, char **argv)
 
 	params.params = 0;
 	/* parameter parsing */
-	while ((ret = getopt_long(argc, argv, "m:s:b:h",
+	while ((ret = getopt_long(argc, argv, "m:s:b:",
 						set_opts, NULL)) != -1) {
 		switch (ret) {
-		case 'h':
-			set_help();
-			return 0;
 		case 'b':
 			if (params.perf_bias)
 				print_wrong_arg_exit();
@@ -110,10 +93,8 @@ int cmd_set(int argc, char **argv)
 		}
 	};
 
-	if (!params.params) {
-		set_help();
-		return -EINVAL;
-	}
+	if (!params.params)
+		print_wrong_arg_exit();
 
 	if (params.sched_mc) {
 		ret = sysfs_set_sched("mc", sched_mc);
diff --git a/tools/power/cpupower/utils/cpupower.c b/tools/power/cpupower/utils/cpupower.c
index 5844ae0f786f..52bee591c1c5 100644
--- a/tools/power/cpupower/utils/cpupower.c
+++ b/tools/power/cpupower/utils/cpupower.c
@@ -11,6 +11,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#include <errno.h>
 
 #include "builtin.h"
 #include "helpers/helpers.h"
@@ -19,13 +20,12 @@
 struct cmd_struct {
 	const char *cmd;
 	int (*main)(int, const char **);
-	void (*usage)(void);
 	int needs_root;
 };
 
 #define ARRAY_SIZE(x) (sizeof(x)/sizeof(x[0]))
 
-int cmd_help(int argc, const char **argv);
+static int cmd_help(int argc, const char **argv);
 
 /* Global cpu_info object available for all binaries
  * Info only retrieved from CPU 0
@@ -44,55 +44,66 @@ int be_verbose;
 static void print_help(void);
 
 static struct cmd_struct commands[] = {
-	{ "frequency-info",	cmd_freq_info,	freq_info_help,	0	},
-	{ "frequency-set",	cmd_freq_set,	freq_set_help,	1	},
-	{ "idle-info",		cmd_idle_info,	idle_info_help,	0	},
-	{ "set",		cmd_set,	set_help,	1	},
-	{ "info",		cmd_info,	info_help,	0	},
-	{ "monitor",		cmd_monitor,	monitor_help,	0	},
-	{ "help",		cmd_help,	print_help,	0	},
-	/*	{ "bench",	cmd_bench,	NULL,		1	}, */
+	{ "frequency-info",	cmd_freq_info,	0	},
+	{ "frequency-set",	cmd_freq_set,	1	},
+	{ "idle-info",		cmd_idle_info,	0	},
+	{ "set",		cmd_set,	1	},
+	{ "info",		cmd_info,	0	},
+	{ "monitor",		cmd_monitor,	0	},
+	{ "help",		cmd_help,	0	},
+	/*	{ "bench",	cmd_bench,	1	}, */
 };
 
-int cmd_help(int argc, const char **argv)
-{
-	unsigned int i;
-
-	if (argc > 1) {
-		for (i = 0; i < ARRAY_SIZE(commands); i++) {
-			struct cmd_struct *p = commands + i;
-			if (strcmp(p->cmd, argv[1]))
-				continue;
-			if (p->usage) {
-				p->usage();
-				return EXIT_SUCCESS;
-			}
-		}
-	}
-	print_help();
-	if (argc == 1)
-		return EXIT_SUCCESS; /* cpupower help */
-	return EXIT_FAILURE;
-}
-
 static void print_help(void)
 {
 	unsigned int i;
 
 #ifdef DEBUG
-	printf(_("cpupower [ -d ][ -c cpulist ] subcommand [ARGS]\n"));
-	printf(_("  -d, --debug      May increase output (stderr) on some subcommands\n"));
+	printf(_("Usage:\tcpupower [-d|--debug] [-c|--cpu cpulist ] <command> [<args>]\n"));
 #else
-	printf(_("cpupower [ -c cpulist ] subcommand [ARGS]\n"));
+	printf(_("Usage:\tcpupower [-c|--cpu cpulist ] <command> [<args>]\n"));
 #endif
-	printf(_("cpupower --version\n"));
-	printf(_("Supported subcommands are:\n"));
+	printf(_("Supported commands are:\n"));
 	for (i = 0; i < ARRAY_SIZE(commands); i++)
 		printf("\t%s\n", commands[i].cmd);
-	printf(_("\nSome subcommands can make use of the -c cpulist option.\n"));
-	printf(_("Look at the general cpupower manpage how to use it\n"));
-	printf(_("and read up the subcommand's manpage whether it is supported.\n"));
-	printf(_("\nUse cpupower help subcommand for getting help for above subcommands.\n"));
+	printf(_("\nNot all commands can make use of the -c cpulist option.\n"));
+	printf(_("\nUse 'cpupower help <command>' for getting help for above commands.\n"));
+}
+
+static int print_man_page(const char *subpage)
+{
+	int len;
+	char *page;
+
+	len = 10; /* enough for "cpupower-" */
+	if (subpage != NULL)
+		len += strlen(subpage);
+
+	page = malloc(len);
+	if (!page)
+		return -ENOMEM;
+
+	sprintf(page, "cpupower");
+	if ((subpage != NULL) && strcmp(subpage, "help")) {
+		strcat(page, "-");
+		strcat(page, subpage);
+	}
+
+	execlp("man", "man", page, NULL);
+
+	/* should not be reached */
+	return -EINVAL;
+}
+
+static int cmd_help(int argc, const char **argv)
+{
+	if (argc > 1) {
+		print_man_page(argv[1]); /* exits within execlp() */
+		return EXIT_FAILURE;
+	}
+
+	print_help();
+	return EXIT_SUCCESS;
 }
 
 static void print_version(void)
diff --git a/tools/power/cpupower/utils/helpers/helpers.h b/tools/power/cpupower/utils/helpers/helpers.h
index 592ee362b877..2747e738efb0 100644
--- a/tools/power/cpupower/utils/helpers/helpers.h
+++ b/tools/power/cpupower/utils/helpers/helpers.h
@@ -16,11 +16,20 @@
 #include "helpers/bitmask.h"
 
 /* Internationalization ****************************/
+#ifdef NLS
+
 #define _(String) gettext(String)
 #ifndef gettext_noop
 #define gettext_noop(String) String
 #endif
 #define N_(String) gettext_noop(String)
+
+#else /* !NLS */
+
+#define _(String) String
+#define N_(String) String
+
+#endif
 /* Internationalization ****************************/
 
 extern int run_as_root;
@@ -96,6 +105,9 @@ struct cpupower_topology {
 		int pkg;
 		int core;
 		int cpu;
+
+		/* flags */
+		unsigned int is_online:1;
 	} *core_info;
 };
 
diff --git a/tools/power/cpupower/utils/helpers/sysfs.c b/tools/power/cpupower/utils/helpers/sysfs.c
index 55e2466674c6..c6343024a611 100644
--- a/tools/power/cpupower/utils/helpers/sysfs.c
+++ b/tools/power/cpupower/utils/helpers/sysfs.c
@@ -56,6 +56,56 @@ static unsigned int sysfs_write_file(const char *path,
 	return (unsigned int) numwrite;
 }
 
+/*
+ * Detect whether a CPU is online
+ *
+ * Returns:
+ *     1 -> if CPU is online
+ *     0 -> if CPU is offline
+ *     negative errno values in error case
+ */
+int sysfs_is_cpu_online(unsigned int cpu)
+{
+	char path[SYSFS_PATH_MAX];
+	int fd;
+	ssize_t numread;
+	unsigned long long value;
+	char linebuf[MAX_LINE_LEN];
+	char *endp;
+	struct stat statbuf;
+
+	snprintf(path, sizeof(path), PATH_TO_CPU "cpu%u", cpu);
+
+	if (stat(path, &statbuf) != 0)
+		return 0;
+
+	/*
+	 * kernel without CONFIG_HOTPLUG_CPU
+	 * -> cpuX directory exists, but not cpuX/online file
+	 */
+	snprintf(path, sizeof(path), PATH_TO_CPU "cpu%u/online", cpu);
+	if (stat(path, &statbuf) != 0)
+		return 1;
+
+	fd = open(path, O_RDONLY);
+	if (fd == -1)
+		return -errno;
+
+	numread = read(fd, linebuf, MAX_LINE_LEN - 1);
+	if (numread < 1) {
+		close(fd);
+		return -EIO;
+	}
+	linebuf[numread] = '\0';
+	close(fd);
+
+	value = strtoull(linebuf, &endp, 0);
+	if (value > 1 || value < 0)
+		return -EINVAL;
+
+	return value;
+}
+
 /* CPUidle idlestate specific /sys/devices/system/cpu/cpuX/cpuidle/ access */
 
 /*
diff --git a/tools/power/cpupower/utils/helpers/sysfs.h b/tools/power/cpupower/utils/helpers/sysfs.h
index f9373e090637..8cb797bbceb0 100644
--- a/tools/power/cpupower/utils/helpers/sysfs.h
+++ b/tools/power/cpupower/utils/helpers/sysfs.h
@@ -7,6 +7,8 @@
 
 extern unsigned int sysfs_read_file(const char *path, char *buf, size_t buflen);
 
+extern int sysfs_is_cpu_online(unsigned int cpu);
+
 extern unsigned long sysfs_get_idlestate_latency(unsigned int cpu,
 						unsigned int idlestate);
 extern unsigned long sysfs_get_idlestate_usage(unsigned int cpu,
diff --git a/tools/power/cpupower/utils/helpers/topology.c b/tools/power/cpupower/utils/helpers/topology.c
index 385ee5c7570c..4eae2c47ba48 100644
--- a/tools/power/cpupower/utils/helpers/topology.c
+++ b/tools/power/cpupower/utils/helpers/topology.c
@@ -41,6 +41,8 @@ struct cpuid_core_info {
 	unsigned int pkg;
 	unsigned int thread;
 	unsigned int cpu;
+	/* flags */
+	unsigned int is_online:1;
 };
 
 static int __compare(const void *t1, const void *t2)
@@ -78,6 +80,8 @@ int get_cpu_topology(struct cpupower_topology *cpu_top)
 		return -ENOMEM;
 	cpu_top->pkgs = cpu_top->cores = 0;
 	for (cpu = 0; cpu < cpus; cpu++) {
+		cpu_top->core_info[cpu].cpu = cpu;
+		cpu_top->core_info[cpu].is_online = sysfs_is_cpu_online(cpu);
 		cpu_top->core_info[cpu].pkg =
 			sysfs_topology_read_file(cpu, "physical_package_id");
 		if ((int)cpu_top->core_info[cpu].pkg != -1 &&
@@ -85,7 +89,6 @@ int get_cpu_topology(struct cpupower_topology *cpu_top)
 			cpu_top->pkgs = cpu_top->core_info[cpu].pkg;
 		cpu_top->core_info[cpu].core =
 			sysfs_topology_read_file(cpu, "core_id");
-		cpu_top->core_info[cpu].cpu = cpu;
 	}
 	cpu_top->pkgs++;
 
diff --git a/tools/power/cpupower/utils/idle_monitor/cpuidle_sysfs.c b/tools/power/cpupower/utils/idle_monitor/cpuidle_sysfs.c
index d048b96a6155..bcd22a1a3970 100644
--- a/tools/power/cpupower/utils/idle_monitor/cpuidle_sysfs.c
+++ b/tools/power/cpupower/utils/idle_monitor/cpuidle_sysfs.c
@@ -134,7 +134,7 @@ static struct cpuidle_monitor *cpuidle_register(void)
 	/* Assume idle state count is the same for all CPUs */
 	cpuidle_sysfs_monitor.hw_states_num = sysfs_get_idlestate_count(0);
 
-	if (cpuidle_sysfs_monitor.hw_states_num == 0)
+	if (cpuidle_sysfs_monitor.hw_states_num <= 0)
 		return NULL;
 
 	for (num = 0; num < cpuidle_sysfs_monitor.hw_states_num; num++) {
diff --git a/tools/power/cpupower/utils/idle_monitor/cpupower-monitor.c b/tools/power/cpupower/utils/idle_monitor/cpupower-monitor.c
index ba4bf068380d..0d6571e418db 100644
--- a/tools/power/cpupower/utils/idle_monitor/cpupower-monitor.c
+++ b/tools/power/cpupower/utils/idle_monitor/cpupower-monitor.c
@@ -43,6 +43,12 @@ static struct cpupower_topology cpu_top;
 /* ToDo: Document this in the manpage */
 static char range_abbr[RANGE_MAX] = { 'T', 'C', 'P', 'M', };
 
+static void print_wrong_arg_exit(void)
+{
+	printf(_("invalid or unknown argument\n"));
+	exit(EXIT_FAILURE);
+}
+
 long long timespec_diff_us(struct timespec start, struct timespec end)
 {
 	struct timespec temp;
@@ -56,21 +62,6 @@ long long timespec_diff_us(struct timespec start, struct timespec end)
 	return (temp.tv_sec * 1000000) + (temp.tv_nsec / 1000);
 }
 
-void monitor_help(void)
-{
-	printf(_("cpupower monitor: [-m <mon1>,[<mon2>],.. ] command\n"));
-	printf(_("cpupower monitor: [-m <mon1>,[<mon2>],.. ] [ -i interval_sec ]\n"));
-	printf(_("cpupower monitor: -l\n"));
-	printf(_("\t command: pass an arbitrary command to measure specific workload\n"));
-	printf(_("\t -i: time intervall to measure for in seconds (default 1)\n"));
-	printf(_("\t -l: list available CPU sleep monitors (for use with -m)\n"));
-	printf(_("\t -m: show specific CPU sleep monitors only (in same order)\n"));
-	printf(_("\t -h: print this help\n"));
-	printf("\n");
-	printf(_("only one of: -l, -m are allowed\nIf none of them is passed,"));
-	printf(_(" all supported monitors are shown\n"));
-}
-
 void print_n_spaces(int n)
 {
 	int x;
@@ -149,6 +140,10 @@ void print_results(int topology_depth, int cpu)
 	unsigned long long result;
 	cstate_t s;
 
+	/* Be careful CPUs may got resorted for pkg value do not just use cpu */
+	if (!bitmask_isbitset(cpus_chosen, cpu_top.core_info[cpu].cpu))
+		return;
+
 	if (topology_depth > 2)
 		printf("%4d|", cpu_top.core_info[cpu].pkg);
 	if (topology_depth > 1)
@@ -190,9 +185,13 @@ void print_results(int topology_depth, int cpu)
 			}
 		}
 	}
-	/* cpu offline */
-	if (cpu_top.core_info[cpu].pkg == -1 ||
-	    cpu_top.core_info[cpu].core == -1) {
+	/*
+	 * The monitor could still provide useful data, for example
+	 * AMD HW counters partly sit in PCI config space.
+	 * It's up to the monitor plug-in to check .is_online, this one
+	 * is just for additional info.
+	 */
+	if (!cpu_top.core_info[cpu].is_online) {
 		printf(_(" *is offline\n"));
 		return;
 	} else
@@ -238,7 +237,6 @@ static void parse_monitor_param(char *param)
 	if (hits == 0) {
 		printf(_("No matching monitor found in %s, "
 			 "try -l option\n"), param);
-		monitor_help();
 		exit(EXIT_FAILURE);
 	}
 	/* Override detected/registerd monitors array with requested one */
@@ -335,37 +333,27 @@ static void cmdline(int argc, char *argv[])
 	int opt;
 	progname = basename(argv[0]);
 
-	while ((opt = getopt(argc, argv, "+hli:m:")) != -1) {
+	while ((opt = getopt(argc, argv, "+li:m:")) != -1) {
 		switch (opt) {
-		case 'h':
-			monitor_help();
-			exit(EXIT_SUCCESS);
 		case 'l':
-			if (mode) {
-				monitor_help();
-				exit(EXIT_FAILURE);
-			}
+			if (mode)
+				print_wrong_arg_exit();
 			mode = list;
 			break;
 		case 'i':
 			/* only allow -i with -m or no option */
-			if (mode && mode != show) {
-				monitor_help();
-				exit(EXIT_FAILURE);
-			}
+			if (mode && mode != show)
+				print_wrong_arg_exit();
 			interval = atoi(optarg);
 			break;
 		case 'm':
-			if (mode) {
-				monitor_help();
-				exit(EXIT_FAILURE);
-			}
+			if (mode)
+				print_wrong_arg_exit();
 			mode = show;
 			show_monitors_param = optarg;
 			break;
 		default:
-			monitor_help();
-			exit(EXIT_FAILURE);
+			print_wrong_arg_exit();
 		}
 	}
 	if (!mode)
@@ -385,6 +373,10 @@ int cmd_monitor(int argc, char **argv)
 		return EXIT_FAILURE;
 	}
 
+	/* Default is: monitor all CPUs */
+	if (bitmask_isallclear(cpus_chosen))
+		bitmask_setall(cpus_chosen);
+
 	dprint("System has up to %d CPU cores\n", cpu_count);
 
 	for (num = 0; all_monitors[num]; num++) {
diff --git a/tools/power/cpupower/utils/idle_monitor/mperf_monitor.c b/tools/power/cpupower/utils/idle_monitor/mperf_monitor.c
index 63ca87a05e5f..5650ab5a2c20 100644
--- a/tools/power/cpupower/utils/idle_monitor/mperf_monitor.c
+++ b/tools/power/cpupower/utils/idle_monitor/mperf_monitor.c
@@ -22,12 +22,15 @@
 
 #define MSR_TSC	0x10
 
+#define MSR_AMD_HWCR 0xc0010015
+
 enum mperf_id { C0 = 0, Cx, AVG_FREQ, MPERF_CSTATE_COUNT };
 
 static int mperf_get_count_percent(unsigned int self_id, double *percent,
 				   unsigned int cpu);
 static int mperf_get_count_freq(unsigned int id, unsigned long long *count,
 				unsigned int cpu);
+static struct timespec time_start, time_end;
 
 static cstate_t mperf_cstates[MPERF_CSTATE_COUNT] = {
 	{
@@ -54,19 +57,33 @@ static cstate_t mperf_cstates[MPERF_CSTATE_COUNT] = {
 	},
 };
 
+enum MAX_FREQ_MODE { MAX_FREQ_SYSFS, MAX_FREQ_TSC_REF };
+static int max_freq_mode;
+/*
+ * The max frequency mperf is ticking at (in C0), either retrieved via:
+ *   1) calculated after measurements if we know TSC ticks at mperf/P0 frequency
+ *   2) cpufreq /sys/devices/.../cpu0/cpufreq/cpuinfo_max_freq at init time
+ * 1. Is preferred as it also works without cpufreq subsystem (e.g. on Xen)
+ */
+static unsigned long max_frequency;
+
 static unsigned long long tsc_at_measure_start;
 static unsigned long long tsc_at_measure_end;
-static unsigned long max_frequency;
 static unsigned long long *mperf_previous_count;
 static unsigned long long *aperf_previous_count;
 static unsigned long long *mperf_current_count;
 static unsigned long long *aperf_current_count;
+
 /* valid flag for all CPUs. If a MSR read failed it will be zero */
 static int *is_valid;
 
 static int mperf_get_tsc(unsigned long long *tsc)
 {
-	return read_msr(0, MSR_TSC, tsc);
+	int ret;
+	ret = read_msr(0, MSR_TSC, tsc);
+	if (ret)
+		dprint("Reading TSC MSR failed, returning %llu\n", *tsc);
+	return ret;
 }
 
 static int mperf_init_stats(unsigned int cpu)
@@ -97,36 +114,11 @@ static int mperf_measure_stats(unsigned int cpu)
 	return 0;
 }
 
-/*
- * get_average_perf()
- *
- * Returns the average performance (also considers boosted frequencies)
- *
- * Input:
- *   aperf_diff: Difference of the aperf register over a time period
- *   mperf_diff: Difference of the mperf register over the same time period
- *   max_freq:   Maximum frequency (P0)
- *
- * Returns:
- *   Average performance over the time period
- */
-static unsigned long get_average_perf(unsigned long long aperf_diff,
-				      unsigned long long mperf_diff)
-{
-	unsigned int perf_percent = 0;
-	if (((unsigned long)(-1) / 100) < aperf_diff) {
-		int shift_count = 7;
-		aperf_diff >>= shift_count;
-		mperf_diff >>= shift_count;
-	}
-	perf_percent = (aperf_diff * 100) / mperf_diff;
-	return (max_frequency * perf_percent) / 100;
-}
-
 static int mperf_get_count_percent(unsigned int id, double *percent,
 				   unsigned int cpu)
 {
 	unsigned long long aperf_diff, mperf_diff, tsc_diff;
+	unsigned long long timediff;
 
 	if (!is_valid[cpu])
 		return -1;
@@ -136,11 +128,19 @@ static int mperf_get_count_percent(unsigned int id, double *percent,
 
 	mperf_diff = mperf_current_count[cpu] - mperf_previous_count[cpu];
 	aperf_diff = aperf_current_count[cpu] - aperf_previous_count[cpu];
-	tsc_diff = tsc_at_measure_end - tsc_at_measure_start;
 
-	*percent = 100.0 * mperf_diff / tsc_diff;
-	dprint("%s: mperf_diff: %llu, tsc_diff: %llu\n",
-	       mperf_cstates[id].name, mperf_diff, tsc_diff);
+	if (max_freq_mode == MAX_FREQ_TSC_REF) {
+		tsc_diff = tsc_at_measure_end - tsc_at_measure_start;
+		*percent = 100.0 * mperf_diff / tsc_diff;
+		dprint("%s: TSC Ref - mperf_diff: %llu, tsc_diff: %llu\n",
+		       mperf_cstates[id].name, mperf_diff, tsc_diff);
+	} else if (max_freq_mode == MAX_FREQ_SYSFS) {
+		timediff = timespec_diff_us(time_start, time_end);
+		*percent = 100.0 * mperf_diff / timediff;
+		dprint("%s: MAXFREQ - mperf_diff: %llu, time_diff: %llu\n",
+		       mperf_cstates[id].name, mperf_diff, timediff);
+	} else
+		return -1;
 
 	if (id == Cx)
 		*percent = 100.0 - *percent;
@@ -154,7 +154,7 @@ static int mperf_get_count_percent(unsigned int id, double *percent,
 static int mperf_get_count_freq(unsigned int id, unsigned long long *count,
 				unsigned int cpu)
 {
-	unsigned long long aperf_diff, mperf_diff;
+	unsigned long long aperf_diff, mperf_diff, time_diff, tsc_diff;
 
 	if (id != AVG_FREQ)
 		return 1;
@@ -165,11 +165,21 @@ static int mperf_get_count_freq(unsigned int id, unsigned long long *count,
 	mperf_diff = mperf_current_count[cpu] - mperf_previous_count[cpu];
 	aperf_diff = aperf_current_count[cpu] - aperf_previous_count[cpu];
 
-	/* Return MHz for now, might want to return KHz if column width is more
-	   generic */
-	*count = get_average_perf(aperf_diff, mperf_diff) / 1000;
-	dprint("%s: %llu\n", mperf_cstates[id].name, *count);
+	if (max_freq_mode == MAX_FREQ_TSC_REF) {
+		/* Calculate max_freq from TSC count */
+		tsc_diff = tsc_at_measure_end - tsc_at_measure_start;
+		time_diff = timespec_diff_us(time_start, time_end);
+		max_frequency = tsc_diff / time_diff;
+	}
 
+	*count = max_frequency * ((double)aperf_diff / mperf_diff);
+	dprint("%s: Average freq based on %s maximum frequency:\n",
+	       mperf_cstates[id].name,
+	       (max_freq_mode == MAX_FREQ_TSC_REF) ? "TSC calculated" : "sysfs read");
+	dprint("%max_frequency: %lu", max_frequency);
+	dprint("aperf_diff: %llu\n", aperf_diff);
+	dprint("mperf_diff: %llu\n", mperf_diff);
+	dprint("avg freq:   %llu\n", *count);
 	return 0;
 }
 
@@ -178,6 +188,7 @@ static int mperf_start(void)
 	int cpu;
 	unsigned long long dbg;
 
+	clock_gettime(CLOCK_REALTIME, &time_start);
 	mperf_get_tsc(&tsc_at_measure_start);
 
 	for (cpu = 0; cpu < cpu_count; cpu++)
@@ -193,32 +204,104 @@ static int mperf_stop(void)
 	unsigned long long dbg;
 	int cpu;
 
-	mperf_get_tsc(&tsc_at_measure_end);
-
 	for (cpu = 0; cpu < cpu_count; cpu++)
 		mperf_measure_stats(cpu);
 
+	mperf_get_tsc(&tsc_at_measure_end);
+	clock_gettime(CLOCK_REALTIME, &time_end);
+
 	mperf_get_tsc(&dbg);
 	dprint("TSC diff: %llu\n", dbg - tsc_at_measure_end);
 
 	return 0;
 }
 
-struct cpuidle_monitor mperf_monitor;
-
-struct cpuidle_monitor *mperf_register(void)
+/*
+ * Mperf register is defined to tick at P0 (maximum) frequency
+ *
+ * Instead of reading out P0 which can be tricky to read out from HW,
+ * we use TSC counter if it reliably ticks at P0/mperf frequency.
+ *
+ * Still try to fall back to:
+ * /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq
+ * on older Intel HW without invariant TSC feature.
+ * Or on AMD machines where TSC does not tick at P0 (do not exist yet, but
+ * it's still double checked (MSR_AMD_HWCR)).
+ *
+ * On these machines the user would still get useful mperf
+ * stats when acpi-cpufreq driver is loaded.
+ */
+static int init_maxfreq_mode(void)
 {
+	int ret;
+	unsigned long long hwcr;
 	unsigned long min;
 
-	if (!(cpupower_cpu_info.caps & CPUPOWER_CAP_APERF))
-		return NULL;
-
-	/* Assume min/max all the same on all cores */
+	if (!cpupower_cpu_info.caps & CPUPOWER_CAP_INV_TSC)
+		goto use_sysfs;
+
+	if (cpupower_cpu_info.vendor == X86_VENDOR_AMD) {
+		/* MSR_AMD_HWCR tells us whether TSC runs at P0/mperf
+		 * freq.
+		 * A test whether hwcr is accessable/available would be:
+		 * (cpupower_cpu_info.family > 0x10 ||
+		 *   cpupower_cpu_info.family == 0x10 &&
+		 *   cpupower_cpu_info.model >= 0x2))
+		 * This should be the case for all aperf/mperf
+		 * capable AMD machines and is therefore safe to test here.
+		 * Compare with Linus kernel git commit: acf01734b1747b1ec4
+		 */
+		ret = read_msr(0, MSR_AMD_HWCR, &hwcr);
+		/*
+		 * If the MSR read failed, assume a Xen system that did
+		 * not explicitly provide access to it and assume TSC works
+		*/
+		if (ret != 0) {
+			dprint("TSC read 0x%x failed - assume TSC working\n",
+			       MSR_AMD_HWCR);
+			return 0;
+		} else if (1 & (hwcr >> 24)) {
+			max_freq_mode = MAX_FREQ_TSC_REF;
+			return 0;
+		} else { /* Use sysfs max frequency if available */ }
+	} else if (cpupower_cpu_info.vendor == X86_VENDOR_INTEL) {
+		/*
+		 * On Intel we assume mperf (in C0) is ticking at same
+		 * rate than TSC
+		 */
+		max_freq_mode = MAX_FREQ_TSC_REF;
+		return 0;
+	}
+use_sysfs:
 	if (cpufreq_get_hardware_limits(0, &min, &max_frequency)) {
 		dprint("Cannot retrieve max freq from cpufreq kernel "
 		       "subsystem\n");
-		return NULL;
+		return -1;
 	}
+	max_freq_mode = MAX_FREQ_SYSFS;
+	return 0;
+}
+
+/*
+ * This monitor provides:
+ *
+ * 1) Average frequency a CPU resided in
+ *    This always works if the CPU has aperf/mperf capabilities
+ *
+ * 2) C0 and Cx (any sleep state) time a CPU resided in
+ *    Works if mperf timer stops ticking in sleep states which
+ *    seem to be the case on all current HW.
+ * Both is directly retrieved from HW registers and is independent
+ * from kernel statistics.
+ */
+struct cpuidle_monitor mperf_monitor;
+struct cpuidle_monitor *mperf_register(void)
+{
+	if (!(cpupower_cpu_info.caps & CPUPOWER_CAP_APERF))
+		return NULL;
+
+	if (init_maxfreq_mode())
+		return NULL;
 
 	/* Free this at program termination */
 	is_valid = calloc(cpu_count, sizeof(int));