tools/power x86_energy_perf_policy: support HWP.EPP

x86_energy_perf_policy(8) was created as an example
of how the user, or upper-level OS, can manage
MSR_IA32_ENERGY_PERF_BIAS (EPB).

Hardware consults EPB when it makes internal decisions
balancing energy-saving vs performance.
For example, should HW quickly or slowly
transition into and out of power-saving idles states?
Should HW quickly or slowly ramp frequency up or down
in response to demand in the turbo-frequency range?

Depending on the processor, EPB may have package, core,
or CPU thread scope.  As such, the only general policy
is to write the same value to EPB on every CPU in the system.

Recent platforms add support for Hardware Performance States (HWP).
HWP effectively extends hardware frequency control from
the opportunistic turbo-frequency range to control the entire
range of available processor frequencies.

Just as turbo-mode used EPB, HWP can use EPB to help decicde
how quickly to ramp frequency and voltage up and down
in response to changing demand.  Indeed, BDX and BDX-DE,
the first processors to support HWP, use EPB for this purpose.

Starting in SKL, HWP no longer looks to EPB for influence.
Instead, it looks in a new MSR specifically for this purpose:
IA32_HWP_REQUEST.Energy_Performance_Preference (HWP.EPP).
HWP.EPP is like EPB, except that it is specific to HWP-mode
frequency selection.  Also, HWP.EPP is defined to have
per CPU-thread scope.

Starting in SKX, IA32_HWP_REQUEST is augmented by
IA32_HWP_REQUEST_PKG -- which has the same function, but is
defined to have package-wide scope.  A new bit in IA32_HWP_REQUEST
determines if it over-rides the IA32_HWP_REQUEST_PKG or not.

Note that HWP-mode can be enabled in several ways.
The "in-band" method is for HWP to be exposed in CPUID,
and for the Linux intel_pstate driver to recognized that,
and thus enable HWP.  In this case, starting in Linux 4.10, intel_pstate
exports cpufreq sysfs attribute "energy_performance_preference"
which can be used to manage HWP.EPP.  This interface can be
used to set HWP.EPP to these values:

0 performance
128 balance_performance (default)
192 balance_power
255 power

Here, x86_energy_performance_policy is updated to use
idential strings and values as intel_pstate.

But HWP-mode may also be enabled by firmware before the OS boots,
and the OS may not be aware of HWP.  In this case, intel_pstate
is not available to provide sysfs attributes, and x86_energy_perf_policy
or a similar utility is invaluable for managing HWP.EPP, for
this utility works the same, no matter if cpufreq is enabled or not.

Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 1303 insertions, 201 deletions

diff --git a/tools/power/x86/x86_energy_perf_policy/x86_energy_perf_policy.c b/tools/power/x86/x86_energy_perf_policy/x86_energy_perf_policy.c
index 40b3e5482f8a..65bbe627a425 100644
--- a/tools/power/x86/x86_energy_perf_policy/x86_energy_perf_policy.c
+++ b/tools/power/x86/x86_energy_perf_policy/x86_energy_perf_policy.c
@@ -3,322 +3,1424 @@
  * policy preference bias on recent X86 processors.
  */
 /*
- * Copyright (c) 2010, Intel Corporation.
+ * Copyright (c) 2010 - 2017 Intel Corporation.
  * Len Brown <len.brown@intel.com>
  *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms and conditions of the GNU General Public License,
- * version 2, as published by the Free Software Foundation.
- *
- * This program is distributed in the hope it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
- * more details.
- *
- * You should have received a copy of the GNU General Public License along with
- * this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ * This program is released under GPL v2
  */
 
+#define _GNU_SOURCE
+#include MSRHEADER
 #include <stdio.h>
 #include <unistd.h>
 #include <sys/types.h>
+#include <sched.h>
 #include <sys/stat.h>
 #include <sys/resource.h>
+#include <getopt.h>
+#include <err.h>
 #include <fcntl.h>
 #include <signal.h>
 #include <sys/time.h>
+#include <limits.h>
 #include <stdlib.h>
 #include <string.h>
+#include <cpuid.h>
+#include <errno.h>
+
+#define	OPTARG_NORMAL			(INT_MAX - 1)
+#define	OPTARG_POWER			(INT_MAX - 2)
+#define	OPTARG_BALANCE_POWER		(INT_MAX - 3)
+#define	OPTARG_BALANCE_PERFORMANCE	(INT_MAX - 4)
+#define	OPTARG_PERFORMANCE		(INT_MAX - 5)
+
+struct msr_hwp_cap {
+	unsigned char highest;
+	unsigned char guaranteed;
+	unsigned char efficient;
+	unsigned char lowest;
+};
 
-unsigned int verbose;		/* set with -v */
-unsigned int read_only;		/* set with -r */
+struct msr_hwp_request {
+	unsigned char hwp_min;
+	unsigned char hwp_max;
+	unsigned char hwp_desired;
+	unsigned char hwp_epp;
+	unsigned int hwp_window;
+	unsigned char hwp_use_pkg;
+} req_update;
+
+unsigned int debug;
+unsigned int verbose;
+unsigned int force;
 char *progname;
-unsigned long long new_bias;
-int cpu = -1;
+int base_cpu;
+unsigned char update_epb;
+unsigned long long new_epb;
+unsigned char turbo_is_enabled;
+unsigned char update_turbo;
+unsigned char turbo_update_value;
+unsigned char update_hwp_epp;
+unsigned char update_hwp_min;
+unsigned char update_hwp_max;
+unsigned char update_hwp_desired;
+unsigned char update_hwp_window;
+unsigned char update_hwp_use_pkg;
+unsigned char update_hwp_enable;
+#define hwp_update_enabled() (update_hwp_enable | update_hwp_epp | update_hwp_max | update_hwp_min | update_hwp_desired | update_hwp_window | update_hwp_use_pkg)
+int max_cpu_num;
+int max_pkg_num;
+#define MAX_PACKAGES 64
+unsigned int first_cpu_in_pkg[MAX_PACKAGES];
+unsigned long long pkg_present_set;
+unsigned long long pkg_selected_set;
+cpu_set_t *cpu_present_set;
+cpu_set_t *cpu_selected_set;
+int genuine_intel;
+
+size_t cpu_setsize;
+
+char *proc_stat = "/proc/stat";
+
+unsigned int has_epb;	/* MSR_IA32_ENERGY_PERF_BIAS */
+unsigned int has_hwp;	/* IA32_PM_ENABLE, IA32_HWP_CAPABILITIES */
+			/* IA32_HWP_REQUEST, IA32_HWP_STATUS */
+unsigned int has_hwp_notify;		/* IA32_HWP_INTERRUPT */
+unsigned int has_hwp_activity_window;	/* IA32_HWP_REQUEST[bits 41:32] */
+unsigned int has_hwp_epp;	/* IA32_HWP_REQUEST[bits 31:24] */
+unsigned int has_hwp_request_pkg;	/* IA32_HWP_REQUEST_PKG */
+
+unsigned int bdx_highest_ratio;
 
 /*
- * Usage:
- *
- * -c cpu: limit action to a single CPU (default is all CPUs)
- * -v: verbose output (can invoke more than once)
- * -r: read-only, don't change any settings
- *
- *  performance
- *	Performance is paramount.
- *	Unwilling to sacrifice any performance
- *	for the sake of energy saving. (hardware default)
- *
- *  normal
- *	Can tolerate minor performance compromise
- *	for potentially significant energy savings.
- *	(reasonable default for most desktops and servers)
- *
- *  powersave
- *	Can tolerate significant performance hit
- *	to maximize energy savings.
- *
- * n
- *	a numerical value to write to the underlying MSR.
+ * maintain compatibility with original implementation, but don't document it:
  */
 void usage(void)
 {
-	printf("%s: [-c cpu] [-v] "
-		"(-r | 'performance' | 'normal' | 'powersave' | n)\n",
-		progname);
+	fprintf(stderr, "%s [options] [scope][field value]\n", progname);
+	fprintf(stderr, "scope: --cpu cpu-list [--hwp-use-pkg #] | --pkg pkg-list\n");
+	fprintf(stderr, "field: --all | --epb | --hwp-epp | --hwp-min | --hwp-max | --hwp-desired\n");
+	fprintf(stderr, "other: --hwp-enable | --turbo-enable (0 | 1) | --help | --force\n");
+	fprintf(stderr,
+		"value: ( # | \"normal\" | \"performance\" | \"balance-performance\" | \"balance-power\"| \"power\")\n");
+	fprintf(stderr, "--hwp-window usec\n");
+
+	fprintf(stderr, "Specify only Energy Performance BIAS (legacy usage):\n");
+	fprintf(stderr, "%s: [-c cpu] [-v] (-r | policy-value )\n", progname);
+
 	exit(1);
 }
 
-#define MSR_IA32_ENERGY_PERF_BIAS	0x000001b0
+/*
+ * If bdx_highest_ratio is set,
+ * then we must translate between MSR format and simple ratio
+ * used on the cmdline.
+ */
+int ratio_2_msr_perf(int ratio)
+{
+	int msr_perf;
+
+	if (!bdx_highest_ratio)
+		return ratio;
+
+	msr_perf = ratio * 255 / bdx_highest_ratio;
+
+	if (debug)
+		fprintf(stderr, "%d = ratio_to_msr_perf(%d)\n", msr_perf, ratio);
+
+	return msr_perf;
+}
+int msr_perf_2_ratio(int msr_perf)
+{
+	int ratio;
+	double d;
+
+	if (!bdx_highest_ratio)
+		return msr_perf;
+
+	d = (double)msr_perf * (double) bdx_highest_ratio / 255.0;
+	d = d + 0.5;	/* round */
+	ratio = (int)d;
+
+	if (debug)
+		fprintf(stderr, "%d = msr_perf_ratio(%d) {%f}\n", ratio, msr_perf, d);
+
+	return ratio;
+}
+int parse_cmdline_epb(int i)
+{
+	if (!has_epb)
+		errx(1, "EPB not enabled on this platform");
+
+	update_epb = 1;
+
+	switch (i) {
+	case OPTARG_POWER:
+		return ENERGY_PERF_BIAS_POWERSAVE;
+	case OPTARG_BALANCE_POWER:
+		return ENERGY_PERF_BIAS_BALANCE_POWERSAVE;
+	case OPTARG_NORMAL:
+		return ENERGY_PERF_BIAS_NORMAL;
+	case OPTARG_BALANCE_PERFORMANCE:
+		return ENERGY_PERF_BIAS_BALANCE_PERFORMANCE;
+	case OPTARG_PERFORMANCE:
+		return ENERGY_PERF_BIAS_PERFORMANCE;
+	}
+	if (i < 0 || i > ENERGY_PERF_BIAS_POWERSAVE)
+		errx(1, "--epb must be from 0 to 15");
+	return i;
+}
+
+#define HWP_CAP_LOWEST 0
+#define HWP_CAP_HIGHEST 255
+
+/*
+ * "performance" changes hwp_min to cap.highest
+ * All others leave it at cap.lowest
+ */
+int parse_cmdline_hwp_min(int i)
+{
+	update_hwp_min = 1;
+
+	switch (i) {
+	case OPTARG_POWER:
+	case OPTARG_BALANCE_POWER:
+	case OPTARG_NORMAL:
+	case OPTARG_BALANCE_PERFORMANCE:
+		return HWP_CAP_LOWEST;
+	case OPTARG_PERFORMANCE:
+		return HWP_CAP_HIGHEST;
+	}
+	return i;
+}
+/*
+ * "power" changes hwp_max to cap.lowest
+ * All others leave it at cap.highest
+ */
+int parse_cmdline_hwp_max(int i)
+{
+	update_hwp_max = 1;
+
+	switch (i) {
+	case OPTARG_POWER:
+		return HWP_CAP_LOWEST;
+	case OPTARG_NORMAL:
+	case OPTARG_BALANCE_POWER:
+	case OPTARG_BALANCE_PERFORMANCE:
+	case OPTARG_PERFORMANCE:
+		return HWP_CAP_HIGHEST;
+	}
+	return i;
+}
+/*
+ * for --hwp-des, all strings leave it in autonomous mode
+ * If you want to change it, you need to explicitly pick a value
+ */
+int parse_cmdline_hwp_desired(int i)
+{
+	update_hwp_desired = 1;
+
+	switch (i) {
+	case OPTARG_POWER:
+	case OPTARG_BALANCE_POWER:
+	case OPTARG_BALANCE_PERFORMANCE:
+	case OPTARG_NORMAL:
+	case OPTARG_PERFORMANCE:
+		return 0;	/* autonomous */
+	}
+	return i;
+}
+
+int parse_cmdline_hwp_window(int i)
+{
+	unsigned int exponent;
+
+	update_hwp_window = 1;
+
+	switch (i) {
+	case OPTARG_POWER:
+	case OPTARG_BALANCE_POWER:
+	case OPTARG_NORMAL:
+	case OPTARG_BALANCE_PERFORMANCE:
+	case OPTARG_PERFORMANCE:
+		return 0;
+	}
+	if (i < 0 || i > 1270000000) {
+		fprintf(stderr, "--hwp-window: 0 for auto; 1 - 1270000000 usec for window duration\n");
+		usage();
+	}
+	for (exponent = 0; ; ++exponent) {
+		if (debug)
+			printf("%d 10^%d\n", i, exponent);
+
+		if (i <= 127)
+			break;
+
+		i = i / 10;
+	}
+	if (debug)
+		fprintf(stderr, "%d*10^%d: 0x%x\n", i, exponent, (exponent << 7) | i);
+
+	return (exponent << 7) | i;
+}
+int parse_cmdline_hwp_epp(int i)
+{
+	update_hwp_epp = 1;
+
+	switch (i) {
+	case OPTARG_POWER:
+		return HWP_EPP_POWERSAVE;
+	case OPTARG_BALANCE_POWER:
+		return HWP_EPP_BALANCE_POWERSAVE;
+	case OPTARG_NORMAL:
+	case OPTARG_BALANCE_PERFORMANCE:
+		return HWP_EPP_BALANCE_PERFORMANCE;
+	case OPTARG_PERFORMANCE:
+		return HWP_EPP_PERFORMANCE;
+	}
+	if (i < 0 || i > 0xff) {
+		fprintf(stderr, "--hwp-epp must be from 0 to 0xff\n");
+		usage();
+	}
+	return i;
+}
+int parse_cmdline_turbo(int i)
+{
+	update_turbo = 1;
+
+	switch (i) {
+	case OPTARG_POWER:
+		return 0;
+	case OPTARG_NORMAL:
+	case OPTARG_BALANCE_POWER:
+	case OPTARG_BALANCE_PERFORMANCE:
+	case OPTARG_PERFORMANCE:
+		return 1;
+	}
+	if (i < 0 || i > 1) {
+		fprintf(stderr, "--turbo-enable: 1 to enable, 0 to disable\n");
+		usage();
+	}
+	return i;
+}
+
+int parse_optarg_string(char *s)
+{
+	int i;
+	char *endptr;
+
+	if (!strncmp(s, "default", 7))
+		return OPTARG_NORMAL;
+
+	if (!strncmp(s, "normal", 6))
+		return OPTARG_NORMAL;
+
+	if (!strncmp(s, "power", 9))
+		return OPTARG_POWER;
+
+	if (!strncmp(s, "balance-power", 17))
+		return OPTARG_BALANCE_POWER;
+
+	if (!strncmp(s, "balance-performance", 19))
+		return OPTARG_BALANCE_PERFORMANCE;
+
+	if (!strncmp(s, "performance", 11))
+		return OPTARG_PERFORMANCE;
+
+	i = strtol(s, &endptr, 0);
+	if (s == endptr) {
+		fprintf(stderr, "no digits in \"%s\"\n", s);
+		usage();
+	}
+	if (i == LONG_MIN || i == LONG_MAX)
+		errx(-1, "%s", s);
+
+	if (i > 0xFF)
+		errx(-1, "%d (0x%x) must be < 256", i, i);
+
+	if (i < 0)
+		errx(-1, "%d (0x%x) must be >= 0", i, i);
+	return i;
+}
+
+void parse_cmdline_all(char *s)
+{
+	force++;
+	update_hwp_enable = 1;
+	req_update.hwp_min = parse_cmdline_hwp_min(parse_optarg_string(s));
+	req_update.hwp_max = parse_cmdline_hwp_max(parse_optarg_string(s));
+	req_update.hwp_epp = parse_cmdline_hwp_epp(parse_optarg_string(s));
+	if (has_epb)
+		new_epb = parse_cmdline_epb(parse_optarg_string(s));
+	turbo_update_value = parse_cmdline_turbo(parse_optarg_string(s));
+	req_update.hwp_desired = parse_cmdline_hwp_desired(parse_optarg_string(s));
+	req_update.hwp_window = parse_cmdline_hwp_window(parse_optarg_string(s));
+}
+
+void validate_cpu_selected_set(void)
+{
+	int cpu;
+
+	if (CPU_COUNT_S(cpu_setsize, cpu_selected_set) == 0)
+		errx(0, "no CPUs requested");
+
+	for (cpu = 0; cpu <= max_cpu_num; ++cpu) {
+		if (CPU_ISSET_S(cpu, cpu_setsize, cpu_selected_set))
+			if (!CPU_ISSET_S(cpu, cpu_setsize, cpu_present_set))
+				errx(1, "Requested cpu% is not present", cpu);
+	}
+}
+
+void parse_cmdline_cpu(char *s)
+{
+	char *startp, *endp;
+	int cpu = 0;
+
+	if (pkg_selected_set) {
+		usage();
+		errx(1, "--cpu | --pkg");
+	}
+	cpu_selected_set = CPU_ALLOC((max_cpu_num + 1));
+	if (cpu_selected_set == NULL)
+		err(1, "cpu_selected_set");
+	CPU_ZERO_S(cpu_setsize, cpu_selected_set);
+
+	for (startp = s; startp && *startp;) {
+
+		if (*startp == ',') {
+			startp++;
+			continue;
+		}
+
+		if (*startp == '-') {
+			int end_cpu;
 
-#define	BIAS_PERFORMANCE		0
-#define BIAS_BALANCE			6
-#define	BIAS_POWERSAVE			15
+			startp++;
+			end_cpu = strtol(startp, &endp, 10);
+			if (startp == endp)
+				continue;
+
+			while (cpu <= end_cpu) {
+				if (cpu > max_cpu_num)
+					errx(1, "Requested cpu%d exceeds max cpu%d", cpu, max_cpu_num);
+				CPU_SET_S(cpu, cpu_setsize, cpu_selected_set);
+				cpu++;
+			}
+			startp = endp;
+			continue;
+		}
+
+		if (strncmp(startp, "all", 3) == 0) {
+			for (cpu = 0; cpu <= max_cpu_num; cpu += 1) {
+				if (CPU_ISSET_S(cpu, cpu_setsize, cpu_present_set))
+					CPU_SET_S(cpu, cpu_setsize, cpu_selected_set);
+			}
+			startp += 3;
+			if (*startp == 0)
+				break;
+		}
+		/* "--cpu even" is not documented */
+		if (strncmp(startp, "even", 4) == 0) {
+			for (cpu = 0; cpu <= max_cpu_num; cpu += 2) {
+				if (CPU_ISSET_S(cpu, cpu_setsize, cpu_present_set))
+					CPU_SET_S(cpu, cpu_setsize, cpu_selected_set);
+			}
+			startp += 4;
+			if (*startp == 0)
+				break;
+		}
+
+		/* "--cpu odd" is not documented */
+		if (strncmp(startp, "odd", 3) == 0) {
+			for (cpu = 1; cpu <= max_cpu_num; cpu += 2) {
+				if (CPU_ISSET_S(cpu, cpu_setsize, cpu_present_set))
+					CPU_SET_S(cpu, cpu_setsize, cpu_selected_set);
+			}
+			startp += 3;
+			if (*startp == 0)
+				break;
+		}
+
+		cpu = strtol(startp, &endp, 10);
+		if (startp == endp)
+			errx(1, "--cpu cpu-set: confused by '%s'", startp);
+		if (cpu > max_cpu_num)
+			errx(1, "Requested cpu%d exceeds max cpu%d", cpu, max_cpu_num);
+		CPU_SET_S(cpu, cpu_setsize, cpu_selected_set);
+		startp = endp;
+	}
+
+	validate_cpu_selected_set();
+
+}
+
+void parse_cmdline_pkg(char *s)
+{
+	char *startp, *endp;
+	int pkg = 0;
+
+	if (cpu_selected_set) {
+		usage();
+		errx(1, "--pkg | --cpu");
+	}
+	pkg_selected_set = 0;
+
+	for (startp = s; startp && *startp;) {
+
+		if (*startp == ',') {
+			startp++;
+			continue;
+		}
+
+		if (*startp == '-') {
+			int end_pkg;
+
+			startp++;
+			end_pkg = strtol(startp, &endp, 10);
+			if (startp == endp)
+				continue;
+
+			while (pkg <= end_pkg) {
+				if (pkg > max_pkg_num)
+					errx(1, "Requested pkg%d exceeds max pkg%d", pkg, max_pkg_num);
+				pkg_selected_set |= 1 << pkg;
+				pkg++;
+			}
+			startp = endp;
+			continue;
+		}
+
+		if (strncmp(startp, "all", 3) == 0) {
+			pkg_selected_set = pkg_present_set;
+			return;
+		}
+
+		pkg = strtol(startp, &endp, 10);
+		if (pkg > max_pkg_num)
+			errx(1, "Requested pkg%d Exceeds max pkg%d", pkg, max_pkg_num);
+		pkg_selected_set |= 1 << pkg;
+		startp = endp;
+	}
+}
+
+void for_packages(unsigned long long pkg_set, int (func)(int))
+{
+	int pkg_num;
+
+	for (pkg_num = 0; pkg_num <= max_pkg_num; ++pkg_num) {
+		if (pkg_set & (1UL << pkg_num))
+			func(pkg_num);
+	}
+}
+
+void print_version(void)
+{
+	printf("x86_energy_perf_policy 17.05.11 (C) Len Brown <len.brown@intel.com>\n");
+}
 
 void cmdline(int argc, char **argv)
 {
 	int opt;
+	int option_index = 0;
+
+	static struct option long_options[] = {
+		{"all",		required_argument,	0, 'a'},
+		{"cpu",		required_argument,	0, 'c'},
+		{"pkg",		required_argument,	0, 'p'},
+		{"debug",	no_argument,		0, 'd'},
+		{"hwp-desired",	required_argument,	0, 'D'},
+		{"epb",	required_argument,	0, 'B'},
+		{"force",	no_argument,	0, 'f'},
+		{"hwp-enable",	no_argument,	0, 'e'},
+		{"help",	no_argument,	0, 'h'},
+		{"hwp-epp",	required_argument,	0, 'P'},
+		{"hwp-min",	required_argument,	0, 'm'},
+		{"hwp-max",	required_argument,	0, 'M'},
+		{"read",	no_argument,		0, 'r'},
+		{"turbo-enable",	required_argument,	0, 't'},
+		{"hwp-use-pkg",	required_argument,	0, 'u'},
+		{"version",	no_argument,		0, 'v'},
+		{"hwp-window",	required_argument,	0, 'w'},
+		{0,		0,			0, 0 }
+	};
 
 	progname = argv[0];
 
-	while ((opt = getopt(argc, argv, "+rvc:")) != -1) {
+	while ((opt = getopt_long_only(argc, argv, "+a:c:dD:E:e:f:m:M:rt:u:vw",
+				long_options, &option_index)) != -1) {
 		switch (opt) {
+		case 'a':
+			parse_cmdline_all(optarg);
+			break;
+		case 'B':
+			new_epb = parse_cmdline_epb(parse_optarg_string(optarg));
+			break;
 		case 'c':
-			cpu = atoi(optarg);
+			parse_cmdline_cpu(optarg);
+			break;
+		case 'e':
+			update_hwp_enable = 1;
+			break;
+		case 'h':
+			usage();
+			break;
+		case 'd':
+			debug++;
+			verbose++;
+			break;
+		case 'f':
+			force++;
+			break;
+		case 'D':
+			req_update.hwp_desired = parse_cmdline_hwp_desired(parse_optarg_string(optarg));
+			break;
+		case 'm':
+			req_update.hwp_min = parse_cmdline_hwp_min(parse_optarg_string(optarg));
+			break;
+		case 'M':
+			req_update.hwp_max = parse_cmdline_hwp_max(parse_optarg_string(optarg));
+			break;
+		case 'p':
+			parse_cmdline_pkg(optarg);
+			break;
+		case 'P':
+			req_update.hwp_epp = parse_cmdline_hwp_epp(parse_optarg_string(optarg));
 			break;
 		case 'r':
-			read_only = 1;
+			/* v1 used -r to specify read-only mode, now the default */
+			break;
+		case 't':
+			turbo_update_value = parse_cmdline_turbo(parse_optarg_string(optarg));
+			break;
+		case 'u':
+			update_hwp_use_pkg++;
+			if (atoi(optarg) == 0)
+				req_update.hwp_use_pkg = 0;
+			else
+				req_update.hwp_use_pkg = 1;
 			break;
 		case 'v':
-			verbose++;
+			print_version();
+			exit(0);
+			break;
+		case 'w':
+			req_update.hwp_window = parse_cmdline_hwp_window(parse_optarg_string(optarg));
 			break;
 		default:
 			usage();
 		}
 	}
-	/* if -r, then should be no additional optind */
-	if (read_only && (argc > optind))
-		usage();
-
 	/*
-	 * if no -r , then must be one additional optind
+	 * v1 allowed "performance"|"normal"|"power" with no policy specifier
+	 * to update BIAS.  Continue to support that, even though no longer documented.
 	 */
-	if (!read_only) {
+	if (argc == optind + 1)
+		new_epb = parse_cmdline_epb(parse_optarg_string(argv[optind]));
 
-		if (argc != optind + 1) {
-			printf("must supply -r or policy param\n");
-			usage();
-			}
+	if (argc > optind + 1) {
+		fprintf(stderr, "stray parameter '%s'\n", argv[optind + 1]);
+		usage();
+	}
+}
 
-		if (!strcmp("performance", argv[optind])) {
-			new_bias = BIAS_PERFORMANCE;
-		} else if (!strcmp("normal", argv[optind])) {
-			new_bias = BIAS_BALANCE;
-		} else if (!strcmp("powersave", argv[optind])) {
-			new_bias = BIAS_POWERSAVE;
-		} else {
-			char *endptr;
-
-			new_bias = strtoull(argv[optind], &endptr, 0);
-			if (endptr == argv[optind] ||
-				new_bias > BIAS_POWERSAVE) {
-					fprintf(stderr, "invalid value: %s\n",
-						argv[optind]);
-				usage();
-			}
-		}
+
+int get_msr(int cpu, int offset, unsigned long long *msr)
+{
+	int retval;
+	char pathname[32];
+	int fd;
+
+	sprintf(pathname, "/dev/cpu/%d/msr", cpu);
+	fd = open(pathname, O_RDONLY);
+	if (fd < 0)
+		err(-1, "%s open failed, try chown or chmod +r /dev/cpu/*/msr, or run as root", pathname);
+
+	retval = pread(fd, msr, sizeof(*msr), offset);
+	if (retval != sizeof(*msr))
+		err(-1, "%s offset 0x%llx read failed", pathname, (unsigned long long)offset);
+
+	if (debug > 1)
+		fprintf(stderr, "get_msr(cpu%d, 0x%X, 0x%llX)\n", cpu, offset, *msr);
+
+	close(fd);
+	return 0;
+}
+
+int put_msr(int cpu, int offset, unsigned long long new_msr)
+{
+	char pathname[32];
+	int retval;
+	int fd;
+
+	sprintf(pathname, "/dev/cpu/%d/msr", cpu);
+	fd = open(pathname, O_RDWR);
+	if (fd < 0)
+		err(-1, "%s open failed, try chown or chmod +r /dev/cpu/*/msr, or run as root", pathname);
+
+	retval = pwrite(fd, &new_msr, sizeof(new_msr), offset);
+	if (retval != sizeof(new_msr))
+		err(-2, "pwrite(cpu%d, offset 0x%x, 0x%llx) = %d", cpu, offset, new_msr, retval);
+
+	close(fd);
+
+	if (debug > 1)
+		fprintf(stderr, "put_msr(cpu%d, 0x%X, 0x%llX)\n", cpu, offset, new_msr);
+
+	return 0;
+}
+
+void print_hwp_cap(int cpu, struct msr_hwp_cap *cap, char *str)
+{
+	if (cpu != -1)
+		printf("cpu%d: ", cpu);
+
+	printf("HWP_CAP: low %d eff %d guar %d high %d\n",
+		cap->lowest, cap->efficient, cap->guaranteed, cap->highest);
+}
+void read_hwp_cap(int cpu, struct msr_hwp_cap *cap, unsigned int msr_offset)
+{
+	unsigned long long msr;
+
+	get_msr(cpu, msr_offset, &msr);
+
+	cap->highest = msr_perf_2_ratio(HWP_HIGHEST_PERF(msr));
+	cap->guaranteed = msr_perf_2_ratio(HWP_GUARANTEED_PERF(msr));
+	cap->efficient = msr_perf_2_ratio(HWP_MOSTEFFICIENT_PERF(msr));
+	cap->lowest = msr_perf_2_ratio(HWP_LOWEST_PERF(msr));
+}
+
+void print_hwp_request(int cpu, struct msr_hwp_request *h, char *str)
+{
+	if (cpu != -1)
+		printf("cpu%d: ", cpu);
+
+	if (str)
+		printf("%s", str);
+
+	printf("HWP_REQ: min %d max %d des %d epp %d window 0x%x (%d*10^%dus) use_pkg %d\n",
+		h->hwp_min, h->hwp_max, h->hwp_desired, h->hwp_epp,
+		h->hwp_window, h->hwp_window & 0x7F, (h->hwp_window >> 7) & 0x7, h->hwp_use_pkg);
+}
+void print_hwp_request_pkg(int pkg, struct msr_hwp_request *h, char *str)
+{
+	printf("pkg%d: ", pkg);
+
+	if (str)
+		printf("%s", str);
+
+	printf("HWP_REQ_PKG: min %d max %d des %d epp %d window 0x%x (%d*10^%dus)\n",
+		h->hwp_min, h->hwp_max, h->hwp_desired, h->hwp_epp,
+		h->hwp_window, h->hwp_window & 0x7F, (h->hwp_window >> 7) & 0x7);
+}
+void read_hwp_request(int cpu, struct msr_hwp_request *hwp_req, unsigned int msr_offset)
+{
+	unsigned long long msr;
+
+	get_msr(cpu, msr_offset, &msr);
+
+	hwp_req->hwp_min = msr_perf_2_ratio((((msr) >> 0) & 0xff));
+	hwp_req->hwp_max = msr_perf_2_ratio((((msr) >> 8) & 0xff));
+	hwp_req->hwp_desired = msr_perf_2_ratio((((msr) >> 16) & 0xff));
+	hwp_req->hwp_epp = (((msr) >> 24) & 0xff);
+	hwp_req->hwp_window = (((msr) >> 32) & 0x3ff);
+	hwp_req->hwp_use_pkg = (((msr) >> 42) & 0x1);
+}
+
+void write_hwp_request(int cpu, struct msr_hwp_request *hwp_req, unsigned int msr_offset)
+{
+	unsigned long long msr = 0;
+
+	if (debug > 1)
+		printf("cpu%d: requesting min %d max %d des %d epp %d window 0x%0x use_pkg %d\n",
+			cpu, hwp_req->hwp_min, hwp_req->hwp_max,
+			hwp_req->hwp_desired, hwp_req->hwp_epp,
+			hwp_req->hwp_window, hwp_req->hwp_use_pkg);
+
+	msr |= HWP_MIN_PERF(ratio_2_msr_perf(hwp_req->hwp_min));
+	msr |= HWP_MAX_PERF(ratio_2_msr_perf(hwp_req->hwp_max));
+	msr |= HWP_DESIRED_PERF(ratio_2_msr_perf(hwp_req->hwp_desired));
+	msr |= HWP_ENERGY_PERF_PREFERENCE(hwp_req->hwp_epp);
+	msr |= HWP_ACTIVITY_WINDOW(hwp_req->hwp_window);
+	msr |= HWP_PACKAGE_CONTROL(hwp_req->hwp_use_pkg);
+
+	put_msr(cpu, msr_offset, msr);
+}
+
+int print_cpu_msrs(int cpu)
+{
+	unsigned long long msr;
+	struct msr_hwp_request req;
+	struct msr_hwp_cap cap;
+
+	if (has_epb) {
+		get_msr(cpu, MSR_IA32_ENERGY_PERF_BIAS, &msr);
+
+		printf("cpu%d: EPB %u\n", cpu, (unsigned int) msr);
 	}
+
+	if (!has_hwp)
+		return 0;
+
+	read_hwp_request(cpu, &req, MSR_HWP_REQUEST);
+	print_hwp_request(cpu, &req, "");
+
+	read_hwp_cap(cpu, &cap, MSR_HWP_CAPABILITIES);
+	print_hwp_cap(cpu, &cap, "");
+
+	return 0;
+}
+
+int print_pkg_msrs(int pkg)
+{
+	struct msr_hwp_request req;
+	unsigned long long msr;
+
+	if (!has_hwp)
+		return 0;
+
+	read_hwp_request(first_cpu_in_pkg[pkg], &req, MSR_HWP_REQUEST_PKG);
+	print_hwp_request_pkg(pkg, &req, "");
+
+	if (has_hwp_notify) {
+		get_msr(first_cpu_in_pkg[pkg], MSR_HWP_INTERRUPT, &msr);
+		fprintf(stderr,
+		"pkg%d: MSR_HWP_INTERRUPT: 0x%08llx (Excursion_Min-%sabled, Guaranteed_Perf_Change-%sabled)\n",
+		pkg, msr,
+		((msr) & 0x2) ? "EN" : "Dis",
+		((msr) & 0x1) ? "EN" : "Dis");
+	}
+	get_msr(first_cpu_in_pkg[pkg], MSR_HWP_STATUS, &msr);
+	fprintf(stderr,
+		"pkg%d: MSR_HWP_STATUS: 0x%08llx (%sExcursion_Min, %sGuaranteed_Perf_Change)\n",
+		pkg, msr,
+		((msr) & 0x4) ? "" : "No-",
+		((msr) & 0x1) ? "" : "No-");
+
+	return 0;
 }
 
 /*
- * validate_cpuid()
- * returns on success, quietly exits on failure (make verbose with -v)
+ * Assumption: All HWP systems have 100 MHz bus clock
  */
-void validate_cpuid(void)
+int ratio_2_sysfs_khz(int ratio)
 {
-	unsigned int eax, ebx, ecx, edx, max_level;
-	unsigned int fms, family, model, stepping;
+	int bclk_khz = 100 * 1000;	/* 100,000 KHz = 100 MHz */
 
-	eax = ebx = ecx = edx = 0;
+	return ratio * bclk_khz;
+}
+/*
+ * If HWP is enabled and cpufreq sysfs attribtes are present,
+ * then update sysfs, so that it will not become
+ * stale when we write to MSRs.
+ * (intel_pstate's max_perf_pct and min_perf_pct will follow cpufreq,
+ *  so we don't have to touch that.)
+ */
+void update_cpufreq_scaling_freq(int is_max, int cpu, unsigned int ratio)
+{
+	char pathname[64];
+	FILE *fp;
+	int retval;
+	int khz;
 
-	asm("cpuid" : "=a" (max_level), "=b" (ebx), "=c" (ecx),
-		"=d" (edx) : "a" (0));
+	sprintf(pathname, "/sys/devices/system/cpu/cpu%d/cpufreq/scaling_%s_freq",
+		cpu, is_max ? "max" : "min");
 
-	if (ebx != 0x756e6547 || edx != 0x49656e69 || ecx != 0x6c65746e) {
-		if (verbose)
-			fprintf(stderr, "%.4s%.4s%.4s != GenuineIntel",
-				(char *)&ebx, (char *)&edx, (char *)&ecx);
-		exit(1);
+	fp = fopen(pathname, "w");
+	if (!fp) {
+		if (debug)
+			perror(pathname);
+		return;
 	}
 
-	asm("cpuid" : "=a" (fms), "=c" (ecx), "=d" (edx) : "a" (1) : "ebx");
-	family = (fms >> 8) & 0xf;
-	model = (fms >> 4) & 0xf;
-	stepping = fms & 0xf;
-	if (family == 6 || family == 0xf)
-		model += ((fms >> 16) & 0xf) << 4;
+	khz = ratio_2_sysfs_khz(ratio);
+	retval = fprintf(fp, "%d", khz);
+	if (retval < 0)
+		if (debug)
+			perror("fprintf");
+	if (debug)
+		printf("echo %d > %s\n", khz, pathname);
 
-	if (verbose > 1)
-		printf("CPUID %d levels family:model:stepping "
-			"0x%x:%x:%x (%d:%d:%d)\n", max_level,
-			family, model, stepping, family, model, stepping);
+	fclose(fp);
+}
 
-	if (!(edx & (1 << 5))) {
-		if (verbose)
-			printf("CPUID: no MSR\n");
-		exit(1);
+/*
+ * We update all sysfs before updating any MSRs because of
+ * bugs in cpufreq/intel_pstate where the sysfs writes
+ * for a CPU may change the min/max values on other CPUS.
+ */
+
+int update_sysfs(int cpu)
+{
+	if (!has_hwp)
+		return 0;
+
+	if (!hwp_update_enabled())
+		return 0;
+
+	if (access("/sys/devices/system/cpu/cpu0/cpufreq", F_OK))
+		return 0;
+
+	if (update_hwp_min)
+		update_cpufreq_scaling_freq(0, cpu, req_update.hwp_min);
+
+	if (update_hwp_max)
+		update_cpufreq_scaling_freq(1, cpu, req_update.hwp_max);
+
+	return 0;
+}
+
+int verify_hwp_req_self_consistency(int cpu, struct msr_hwp_request *req)
+{
+	/* fail if min > max requested */
+	if (req->hwp_min > req->hwp_max) {
+		errx(1, "cpu%d: requested hwp-min %d > hwp_max %d",
+			cpu, req->hwp_min, req->hwp_max);
 	}
 
-	/*
-	 * Support for MSR_IA32_ENERGY_PERF_BIAS
-	 * is indicated by CPUID.06H.ECX.bit3
-	 */
-	asm("cpuid" : "=a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx) : "a" (6));
-	if (verbose)
-		printf("CPUID.06H.ECX: 0x%x\n", ecx);
-	if (!(ecx & (1 << 3))) {
-		if (verbose)
-			printf("CPUID: No MSR_IA32_ENERGY_PERF_BIAS\n");
-		exit(1);
+	/* fail if desired > max requestd */
+	if (req->hwp_desired && (req->hwp_desired > req->hwp_max)) {
+		errx(1, "cpu%d: requested hwp-desired %d > hwp_max %d",
+			cpu, req->hwp_desired, req->hwp_max);
 	}
-	return;	/* success */
+	/* fail if desired < min requestd */
+	if (req->hwp_desired && (req->hwp_desired < req->hwp_min)) {
+		errx(1, "cpu%d: requested hwp-desired %d < requested hwp_min %d",
+			cpu, req->hwp_desired, req->hwp_min);
+	}
+
+	return 0;
 }
 
-unsigned long long get_msr(int cpu, int offset)
+int check_hwp_request_v_hwp_capabilities(int cpu, struct msr_hwp_request *req, struct msr_hwp_cap *cap)
 {
-	unsigned long long msr;
-	char msr_path[32];
-	int retval;
-	int fd;
+	if (update_hwp_max) {
+		if (req->hwp_max > cap->highest)
+			errx(1, "cpu%d: requested max %d > capabilities highest %d, use --force?",
+				cpu, req->hwp_max, cap->highest);
+		if (req->hwp_max < cap->lowest)
+			errx(1, "cpu%d: requested max %d < capabilities lowest %d, use --force?",
+				cpu, req->hwp_max, cap->lowest);
+	}
 
-	sprintf(msr_path, "/dev/cpu/%d/msr", cpu);
-	fd = open(msr_path, O_RDONLY);
-	if (fd < 0) {
-		printf("Try \"# modprobe msr\"\n");
-		perror(msr_path);
-		exit(1);
+	if (update_hwp_min) {
+		if (req->hwp_min > cap->highest)
+			errx(1, "cpu%d: requested min %d > capabilities highest %d, use --force?",
+				cpu, req->hwp_min, cap->highest);
+		if (req->hwp_min < cap->lowest)
+			errx(1, "cpu%d: requested min %d < capabilities lowest %d, use --force?",
+				cpu, req->hwp_min, cap->lowest);
 	}
 
-	retval = pread(fd, &msr, sizeof msr, offset);
+	if (update_hwp_min && update_hwp_max && (req->hwp_min > req->hwp_max))
+		errx(1, "cpu%d: requested min %d > requested max %d",
+			cpu, req->hwp_min, req->hwp_max);
 
-	if (retval != sizeof msr) {
-		printf("pread cpu%d 0x%x = %d\n", cpu, offset, retval);
-		exit(-2);
+	if (update_hwp_desired && req->hwp_desired) {
+		if (req->hwp_desired > req->hwp_max)
+			errx(1, "cpu%d: requested desired %d > requested max %d, use --force?",
+				cpu, req->hwp_desired, req->hwp_max);
+		if (req->hwp_desired < req->hwp_min)
+			errx(1, "cpu%d: requested desired %d < requested min %d, use --force?",
+				cpu, req->hwp_desired, req->hwp_min);
+		if (req->hwp_desired < cap->lowest)
+			errx(1, "cpu%d: requested desired %d < capabilities lowest %d, use --force?",
+				cpu, req->hwp_desired, cap->lowest);
+		if (req->hwp_desired > cap->highest)
+			errx(1, "cpu%d: requested desired %d > capabilities highest %d, use --force?",
+				cpu, req->hwp_desired, cap->highest);
 	}
-	close(fd);
-	return msr;
+
+	return 0;
 }
 
-unsigned long long  put_msr(int cpu, unsigned long long new_msr, int offset)
+int update_hwp_request(int cpu)
 {
-	unsigned long long old_msr;
-	char msr_path[32];
-	int retval;
-	int fd;
+	struct msr_hwp_request req;
+	struct msr_hwp_cap cap;
+
+	int msr_offset = MSR_HWP_REQUEST;
+
+	read_hwp_request(cpu, &req, msr_offset);
+	if (debug)
+		print_hwp_request(cpu, &req, "old: ");
+
+	if (update_hwp_min)
+		req.hwp_min = req_update.hwp_min;
+
+	if (update_hwp_max)
+		req.hwp_max = req_update.hwp_max;
+
+	if (update_hwp_desired)
+		req.hwp_desired = req_update.hwp_desired;
+
+	if (update_hwp_window)
+		req.hwp_window = req_update.hwp_window;
+
+	if (update_hwp_epp)
+		req.hwp_epp = req_update.hwp_epp;
+
+	req.hwp_use_pkg = req_update.hwp_use_pkg;
+
+	read_hwp_cap(cpu, &cap, MSR_HWP_CAPABILITIES);
+	if (debug)
+		print_hwp_cap(cpu, &cap, "");
+
+	if (!force)
+		check_hwp_request_v_hwp_capabilities(cpu, &req, &cap);
+
+	verify_hwp_req_self_consistency(cpu, &req);
 
-	sprintf(msr_path, "/dev/cpu/%d/msr", cpu);
-	fd = open(msr_path, O_RDWR);
-	if (fd < 0) {
-		perror(msr_path);
-		exit(1);
+	write_hwp_request(cpu, &req, msr_offset);
+
+	if (debug) {
+		read_hwp_request(cpu, &req, msr_offset);
+		print_hwp_request(cpu, &req, "new: ");
 	}
+	return 0;
+}
+int update_hwp_request_pkg(int pkg)
+{
+	struct msr_hwp_request req;
+	struct msr_hwp_cap cap;
+	int cpu = first_cpu_in_pkg[pkg];
+
+	int msr_offset = MSR_HWP_REQUEST_PKG;
+
+	read_hwp_request(cpu, &req, msr_offset);
+	if (debug)
+		print_hwp_request_pkg(pkg, &req, "old: ");
+
+	if (update_hwp_min)
+		req.hwp_min = req_update.hwp_min;
+
+	if (update_hwp_max)
+		req.hwp_max = req_update.hwp_max;
+
+	if (update_hwp_desired)
+		req.hwp_desired = req_update.hwp_desired;
+
+	if (update_hwp_window)
+		req.hwp_window = req_update.hwp_window;
+
+	if (update_hwp_epp)
+		req.hwp_epp = req_update.hwp_epp;
+
+	read_hwp_cap(cpu, &cap, MSR_HWP_CAPABILITIES);
+	if (debug)
+		print_hwp_cap(cpu, &cap, "");
+
+	if (!force)
+		check_hwp_request_v_hwp_capabilities(cpu, &req, &cap);
+
+	verify_hwp_req_self_consistency(cpu, &req);
+
+	write_hwp_request(cpu, &req, msr_offset);
 
-	retval = pread(fd, &old_msr, sizeof old_msr, offset);
-	if (retval != sizeof old_msr) {
-		perror("pwrite");
-		printf("pread cpu%d 0x%x = %d\n", cpu, offset, retval);
-		exit(-2);
+	if (debug) {
+		read_hwp_request(cpu, &req, msr_offset);
+		print_hwp_request_pkg(pkg, &req, "new: ");
 	}
+	return 0;
+}
+
+int enable_hwp_on_cpu(int cpu)
+{
+	unsigned long long msr;
+
+	get_msr(cpu, MSR_PM_ENABLE, &msr);
+	put_msr(cpu, MSR_PM_ENABLE, 1);
+
+	if (verbose)
+		printf("cpu%d: MSR_PM_ENABLE old: %d new: %d\n", cpu, (unsigned int) msr, 1);
+
+	return 0;
+}
+
+int update_cpu_msrs(int cpu)
+{
+	unsigned long long msr;
+
 
-	retval = pwrite(fd, &new_msr, sizeof new_msr, offset);
-	if (retval != sizeof new_msr) {
-		perror("pwrite");
-		printf("pwrite cpu%d 0x%x = %d\n", cpu, offset, retval);
-		exit(-2);
+	if (update_epb) {
+		get_msr(cpu, MSR_IA32_ENERGY_PERF_BIAS, &msr);
+		put_msr(cpu, MSR_IA32_ENERGY_PERF_BIAS, new_epb);
+
+		if (verbose)
+			printf("cpu%d: ENERGY_PERF_BIAS old: %d new: %d\n",
+				cpu, (unsigned int) msr, (unsigned int) new_epb);
 	}
 
-	close(fd);
+	if (update_turbo) {
+		int turbo_is_present_and_disabled;
+
+		get_msr(cpu, MSR_IA32_MISC_ENABLE, &msr);
+
+		turbo_is_present_and_disabled = ((msr & MSR_IA32_MISC_ENABLE_TURBO_DISABLE) != 0);
+
+		if (turbo_update_value == 1)	{
+			if (turbo_is_present_and_disabled) {
+				msr &= ~MSR_IA32_MISC_ENABLE_TURBO_DISABLE;
+				put_msr(cpu, MSR_IA32_MISC_ENABLE, msr);
+				if (verbose)
+					printf("cpu%d: turbo ENABLE\n", cpu);
+			}
+		} else {
+			/*
+			 * if "turbo_is_enabled" were known to be describe this cpu
+			 * then we could use it here to skip redundant disable requests.
+			 * but cpu may be in a different package, so we always write.
+			 */
+			msr |= MSR_IA32_MISC_ENABLE_TURBO_DISABLE;
+			put_msr(cpu, MSR_IA32_MISC_ENABLE, msr);
+			if (verbose)
+				printf("cpu%d: turbo DISABLE\n", cpu);
+		}
+	}
+
+	if (!has_hwp)
+		return 0;
+
+	if (!hwp_update_enabled())
+		return 0;
+
+	update_hwp_request(cpu);
+	return 0;
+}
+
+/*
+ * Open a file, and exit on failure
+ */
+FILE *fopen_or_die(const char *path, const char *mode)
+{
+	FILE *filep = fopen(path, "r");
 
-	return old_msr;
+	if (!filep)
+		err(1, "%s: open failed", path);
+	return filep;
 }
 
-void print_msr(int cpu)
+unsigned int get_pkg_num(int cpu)
 {
-	printf("cpu%d: 0x%016llx\n",
-		cpu, get_msr(cpu, MSR_IA32_ENERGY_PERF_BIAS));
+	FILE *fp;
+	char pathname[128];
+	unsigned int pkg;
+	int retval;
+
+	sprintf(pathname, "/sys/devices/system/cpu/cpu%d/topology/physical_package_id", cpu);
+
+	fp = fopen_or_die(pathname, "r");
+	retval = fscanf(fp, "%d\n", &pkg);
+	if (retval != 1)
+		errx(1, "%s: failed to parse", pathname);
+	return pkg;
 }
 
-void update_msr(int cpu)
+int set_max_cpu_pkg_num(int cpu)
 {
-	unsigned long long previous_msr;
+	unsigned int pkg;
 
-	previous_msr = put_msr(cpu, new_bias, MSR_IA32_ENERGY_PERF_BIAS);
+	if (max_cpu_num < cpu)
+		max_cpu_num = cpu;
 
-	if (verbose)
-		printf("cpu%d  msr0x%x 0x%016llx -> 0x%016llx\n",
-			cpu, MSR_IA32_ENERGY_PERF_BIAS, previous_msr, new_bias);
+	pkg = get_pkg_num(cpu);
+
+	if (pkg >= MAX_PACKAGES)
+		errx(1, "cpu%d: %d >= MAX_PACKAGES (%d)", cpu, pkg, MAX_PACKAGES);
+
+	if (pkg > max_pkg_num)
+		max_pkg_num = pkg;
 
-	return;
+	if ((pkg_present_set & (1ULL << pkg)) == 0) {
+		pkg_present_set |= (1ULL << pkg);
+		first_cpu_in_pkg[pkg] = cpu;
+	}
+
+	return 0;
+}
+int mark_cpu_present(int cpu)
+{
+	CPU_SET_S(cpu, cpu_setsize, cpu_present_set);
+	return 0;
 }
 
-char *proc_stat = "/proc/stat";
 /*
- * run func() on every cpu in /dev/cpu
+ * run func(cpu) on every cpu in /proc/stat
+ * return max_cpu number
  */
-void for_every_cpu(void (func)(int))
+int for_all_proc_cpus(int (func)(int))
 {
 	FILE *fp;
+	int cpu_num;
 	int retval;
 
-	fp = fopen(proc_stat, "r");
-	if (fp == NULL) {
-		perror(proc_stat);
-		exit(1);
-	}
+	fp = fopen_or_die(proc_stat, "r");
 
 	retval = fscanf(fp, "cpu %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d\n");
-	if (retval != 0) {
-		perror("/proc/stat format");
-		exit(1);
-	}
+	if (retval != 0)
+		err(1, "%s: failed to parse format", proc_stat);
 
 	while (1) {
-		int cpu;
-
-		retval = fscanf(fp,
-			"cpu%u %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d\n",
-			&cpu);
+		retval = fscanf(fp, "cpu%u %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d\n", &cpu_num);
 		if (retval != 1)
 			break;
 
-		func(cpu);
+		retval = func(cpu_num);
+		if (retval) {
+			fclose(fp);
+			return retval;
+		}
 	}
 	fclose(fp);
+	return 0;
+}
+
+void for_all_cpus_in_set(size_t set_size, cpu_set_t *cpu_set, int (func)(int))
+{
+	int cpu_num;
+
+	for (cpu_num = 0; cpu_num <= max_cpu_num; ++cpu_num)
+		if (CPU_ISSET_S(cpu_num, set_size, cpu_set))
+			func(cpu_num);
+}
+
+void init_data_structures(void)
+{
+	for_all_proc_cpus(set_max_cpu_pkg_num);
+
+	cpu_setsize = CPU_ALLOC_SIZE((max_cpu_num + 1));
+
+	cpu_present_set = CPU_ALLOC((max_cpu_num + 1));
+	if (cpu_present_set == NULL)
+		err(3, "CPU_ALLOC");
+	CPU_ZERO_S(cpu_setsize, cpu_present_set);
+	for_all_proc_cpus(mark_cpu_present);
+}
+
+/* clear has_hwp if it is not enable (or being enabled) */
+
+void verify_hwp_is_enabled(void)
+{
+	unsigned long long msr;
+
+	if (!has_hwp)	/* set in early_cpuid() */
+		return;
+
+	/* MSR_PM_ENABLE[1] == 1 if HWP is enabled and MSRs visible */
+	get_msr(base_cpu, MSR_PM_ENABLE, &msr);
+	if ((msr & 1) == 0) {
+		fprintf(stderr, "HWP can be enabled using '--hwp-enable'\n");
+		has_hwp = 0;
+		return;
+	}
+}
+
+int req_update_bounds_check(void)
+{
+	if (!hwp_update_enabled())
+		return 0;
+
+	/* fail if min > max requested */
+	if ((update_hwp_max && update_hwp_min) &&
+	    (req_update.hwp_min > req_update.hwp_max)) {
+		printf("hwp-min %d > hwp_max %d\n", req_update.hwp_min, req_update.hwp_max);
+		return -EINVAL;
+	}
+
+	/* fail if desired > max requestd */
+	if (req_update.hwp_desired && update_hwp_max &&
+	    (req_update.hwp_desired > req_update.hwp_max)) {
+		printf("hwp-desired cannot be greater than hwp_max\n");
+		return -EINVAL;
+	}
+	/* fail if desired < min requestd */
+	if (req_update.hwp_desired && update_hwp_min &&
+	    (req_update.hwp_desired < req_update.hwp_min)) {
+		printf("hwp-desired cannot be less than hwp_min\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+void set_base_cpu(void)
+{
+	base_cpu = sched_getcpu();
+	if (base_cpu < 0)
+		err(-ENODEV, "No valid cpus found");
+}
+
+
+void probe_dev_msr(void)
+{
+	struct stat sb;
+	char pathname[32];
+
+	sprintf(pathname, "/dev/cpu/%d/msr", base_cpu);
+	if (stat(pathname, &sb))
+		if (system("/sbin/modprobe msr > /dev/null 2>&1"))
+			err(-5, "no /dev/cpu/0/msr, Try \"# modprobe msr\" ");
+}
+/*
+ * early_cpuid()
+ * initialize turbo_is_enabled, has_hwp, has_epb
+ * before cmdline is parsed
+ */
+void early_cpuid(void)
+{
+	unsigned int eax, ebx, ecx, edx, max_level;
+	unsigned int fms, family, model;
+
+	__get_cpuid(0, &max_level, &ebx, &ecx, &edx);
+
+	if (max_level < 6)
+		errx(1, "Processor not supported\n");
+
+	__get_cpuid(1, &fms, &ebx, &ecx, &edx);
+	family = (fms >> 8) & 0xf;
+	model = (fms >> 4) & 0xf;
+	if (family == 6 || family == 0xf)
+		model += ((fms >> 16) & 0xf) << 4;
+
+	if (model == 0x4F) {
+		unsigned long long msr;
+
+		get_msr(base_cpu, MSR_TURBO_RATIO_LIMIT, &msr);
+
+		bdx_highest_ratio = msr & 0xFF;
+	}
+
+	__get_cpuid(0x6, &eax, &ebx, &ecx, &edx);
+	turbo_is_enabled = (eax >> 1) & 1;
+	has_hwp = (eax >> 7) & 1;
+	has_epb = (ecx >> 3) & 1;
+}
+
+/*
+ * parse_cpuid()
+ * set
+ * has_hwp, has_hwp_notify, has_hwp_activity_window, has_hwp_epp, has_hwp_request_pkg, has_epb
+ */
+void parse_cpuid(void)
+{
+	unsigned int eax, ebx, ecx, edx, max_level;
+	unsigned int fms, family, model, stepping;
+
+	eax = ebx = ecx = edx = 0;
+
+	__get_cpuid(0, &max_level, &ebx, &ecx, &edx);
+
+	if (ebx == 0x756e6547 && edx == 0x49656e69 && ecx == 0x6c65746e)
+		genuine_intel = 1;
+
+	if (debug)
+		fprintf(stderr, "CPUID(0): %.4s%.4s%.4s ",
+			(char *)&ebx, (char *)&edx, (char *)&ecx);
+
+	__get_cpuid(1, &fms, &ebx, &ecx, &edx);
+	family = (fms >> 8) & 0xf;
+	model = (fms >> 4) & 0xf;
+	stepping = fms & 0xf;
+	if (family == 6 || family == 0xf)
+		model += ((fms >> 16) & 0xf) << 4;
+
+	if (debug) {
+		fprintf(stderr, "%d CPUID levels; family:model:stepping 0x%x:%x:%x (%d:%d:%d)\n",
+			max_level, family, model, stepping, family, model, stepping);
+		fprintf(stderr, "CPUID(1): %s %s %s %s %s %s %s %s\n",
+			ecx & (1 << 0) ? "SSE3" : "-",
+			ecx & (1 << 3) ? "MONITOR" : "-",
+			ecx & (1 << 7) ? "EIST" : "-",
+			ecx & (1 << 8) ? "TM2" : "-",
+			edx & (1 << 4) ? "TSC" : "-",
+			edx & (1 << 5) ? "MSR" : "-",
+			edx & (1 << 22) ? "ACPI-TM" : "-",
+			edx & (1 << 29) ? "TM" : "-");
+	}
+
+	if (!(edx & (1 << 5)))
+		errx(1, "CPUID: no MSR");
+
+
+	__get_cpuid(0x6, &eax, &ebx, &ecx, &edx);
+	/* turbo_is_enabled already set */
+	/* has_hwp already set */
+	has_hwp_notify = eax & (1 << 8);
+	has_hwp_activity_window = eax & (1 << 9);
+	has_hwp_epp = eax & (1 << 10);
+	has_hwp_request_pkg = eax & (1 << 11);
+
+	if (!has_hwp_request_pkg && update_hwp_use_pkg)
+		errx(1, "--hwp-use-pkg is not available on this hardware");
+
+	/* has_epb already set */
+
+	if (debug)
+		fprintf(stderr,
+			"CPUID(6): %sTURBO, %sHWP, %sHWPnotify, %sHWPwindow, %sHWPepp, %sHWPpkg, %sEPB\n",
+			turbo_is_enabled ? "" : "No-",
+			has_hwp ? "" : "No-",
+			has_hwp_notify ? "" : "No-",
+			has_hwp_activity_window ? "" : "No-",
+			has_hwp_epp ? "" : "No-",
+			has_hwp_request_pkg ? "" : "No-",
+			has_epb ? "" : "No-");
+
+	return;	/* success */
 }
 
 int main(int argc, char **argv)
 {
+	set_base_cpu();
+	probe_dev_msr();
+	init_data_structures();
+
+	early_cpuid();	/* initial cpuid parse before cmdline */
+
 	cmdline(argc, argv);
 
-	if (verbose > 1)
-		printf("x86_energy_perf_policy Nov 24, 2010"
-				" - Len Brown <lenb@kernel.org>\n");
-	if (verbose > 1 && !read_only)
-		printf("new_bias %lld\n", new_bias);
-
-	validate_cpuid();
-
-	if (cpu != -1) {
-		if (read_only)
-			print_msr(cpu);
-		else
-			update_msr(cpu);
-	} else {
-		if (read_only)
-			for_every_cpu(print_msr);
-		else
-			for_every_cpu(update_msr);
+	if (debug)
+		print_version();
+
+	parse_cpuid();
+
+	 /* If CPU-set and PKG-set are not initialized, default to all CPUs */
+	if ((cpu_selected_set == 0) && (pkg_selected_set == 0))
+		cpu_selected_set = cpu_present_set;
+
+	/*
+	 * If HWP is being enabled, do it now, so that subsequent operations
+	 * that access HWP registers can work.
+	 */
+	if (update_hwp_enable)
+		for_all_cpus_in_set(cpu_setsize, cpu_selected_set, enable_hwp_on_cpu);
+
+	/* If HWP present, but disabled, warn and ignore from here forward */
+	verify_hwp_is_enabled();
+
+	if (req_update_bounds_check())
+		return -EINVAL;
+
+	/* display information only, no updates to settings */
+	if (!update_epb && !update_turbo && !hwp_update_enabled()) {
+		if (cpu_selected_set)
+			for_all_cpus_in_set(cpu_setsize, cpu_selected_set, print_cpu_msrs);
+
+		if (has_hwp_request_pkg) {
+			if (pkg_selected_set == 0)
+				pkg_selected_set = pkg_present_set;
+
+			for_packages(pkg_selected_set, print_pkg_msrs);
+		}
+
+		return 0;
 	}
 
+	/* update CPU set */
+	if (cpu_selected_set) {
+		for_all_cpus_in_set(cpu_setsize, cpu_selected_set, update_sysfs);
+		for_all_cpus_in_set(cpu_setsize, cpu_selected_set, update_cpu_msrs);
+	} else if (pkg_selected_set)
+		for_packages(pkg_selected_set, update_hwp_request_pkg);
+
 	return 0;
 }