Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 849 insertions, 0 deletions

diff --git a/drivers/thermal/intel/intel_powerclamp.c b/drivers/thermal/intel/intel_powerclamp.c
new file mode 100644
index 0000000000..5ac5cb60ba
--- /dev/null
+++ b/drivers/thermal/intel/intel_powerclamp.c
@@ -0,0 +1,849 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * intel_powerclamp.c - package c-state idle injection
+ *
+ * Copyright (c) 2012-2023, Intel Corporation.
+ *
+ * Authors:
+ *     Arjan van de Ven <arjan@linux.intel.com>
+ *     Jacob Pan <jacob.jun.pan@linux.intel.com>
+ *
+ *	TODO:
+ *           1. better handle wakeup from external interrupts, currently a fixed
+ *              compensation is added to clamping duration when excessive amount
+ *              of wakeups are observed during idle time. the reason is that in
+ *              case of external interrupts without need for ack, clamping down
+ *              cpu in non-irq context does not reduce irq. for majority of the
+ *              cases, clamping down cpu does help reduce irq as well, we should
+ *              be able to differentiate the two cases and give a quantitative
+ *              solution for the irqs that we can control. perhaps based on
+ *              get_cpu_iowait_time_us()
+ *
+ *	     2. synchronization with other hw blocks
+ */
+
+#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/cpu.h>
+#include <linux/thermal.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+#include <linux/idle_inject.h>
+
+#include <asm/msr.h>
+#include <asm/mwait.h>
+#include <asm/cpu_device_id.h>
+
+#define MAX_TARGET_RATIO (100U)
+/* For each undisturbed clamping period (no extra wake ups during idle time),
+ * we increment the confidence counter for the given target ratio.
+ * CONFIDENCE_OK defines the level where runtime calibration results are
+ * valid.
+ */
+#define CONFIDENCE_OK (3)
+/* Default idle injection duration, driver adjust sleep time to meet target
+ * idle ratio. Similar to frequency modulation.
+ */
+#define DEFAULT_DURATION_JIFFIES (6)
+
+static unsigned int target_mwait;
+static struct dentry *debug_dir;
+static bool poll_pkg_cstate_enable;
+
+/* Idle ratio observed using package C-state counters */
+static unsigned int current_ratio;
+
+/* Skip the idle injection till set to true */
+static bool should_skip;
+
+struct powerclamp_data {
+	unsigned int cpu;
+	unsigned int count;
+	unsigned int guard;
+	unsigned int window_size_now;
+	unsigned int target_ratio;
+	bool clamping;
+};
+
+static struct powerclamp_data powerclamp_data;
+
+static struct thermal_cooling_device *cooling_dev;
+
+static DEFINE_MUTEX(powerclamp_lock);
+
+/* This duration is in microseconds */
+static unsigned int duration;
+static unsigned int pkg_cstate_ratio_cur;
+static unsigned int window_size;
+
+static int duration_set(const char *arg, const struct kernel_param *kp)
+{
+	int ret = 0;
+	unsigned long new_duration;
+
+	ret = kstrtoul(arg, 10, &new_duration);
+	if (ret)
+		goto exit;
+	if (new_duration > 25 || new_duration < 6) {
+		pr_err("Out of recommended range %lu, between 6-25ms\n",
+			new_duration);
+		ret = -EINVAL;
+		goto exit;
+	}
+
+	mutex_lock(&powerclamp_lock);
+	duration = clamp(new_duration, 6ul, 25ul) * 1000;
+	mutex_unlock(&powerclamp_lock);
+exit:
+
+	return ret;
+}
+
+static int duration_get(char *buf, const struct kernel_param *kp)
+{
+	int ret;
+
+	mutex_lock(&powerclamp_lock);
+	ret = sysfs_emit(buf, "%d\n", duration / 1000);
+	mutex_unlock(&powerclamp_lock);
+
+	return ret;
+}
+
+static const struct kernel_param_ops duration_ops = {
+	.set = duration_set,
+	.get = duration_get,
+};
+
+module_param_cb(duration, &duration_ops, NULL, 0644);
+MODULE_PARM_DESC(duration, "forced idle time for each attempt in msec.");
+
+#define DEFAULT_MAX_IDLE	50
+#define MAX_ALL_CPU_IDLE	75
+
+static u8 max_idle = DEFAULT_MAX_IDLE;
+
+static cpumask_var_t idle_injection_cpu_mask;
+
+static int allocate_copy_idle_injection_mask(const struct cpumask *copy_mask)
+{
+	if (cpumask_available(idle_injection_cpu_mask))
+		goto copy_mask;
+
+	/* This mask is allocated only one time and freed during module exit */
+	if (!alloc_cpumask_var(&idle_injection_cpu_mask, GFP_KERNEL))
+		return -ENOMEM;
+
+copy_mask:
+	cpumask_copy(idle_injection_cpu_mask, copy_mask);
+
+	return 0;
+}
+
+/* Return true if the cpumask and idle percent combination is invalid */
+static bool check_invalid(cpumask_var_t mask, u8 idle)
+{
+	if (cpumask_equal(cpu_present_mask, mask) && idle > MAX_ALL_CPU_IDLE)
+		return true;
+
+	return false;
+}
+
+static int cpumask_set(const char *arg, const struct kernel_param *kp)
+{
+	cpumask_var_t new_mask;
+	int ret;
+
+	mutex_lock(&powerclamp_lock);
+
+	/* Can't set mask when cooling device is in use */
+	if (powerclamp_data.clamping) {
+		ret = -EAGAIN;
+		goto skip_cpumask_set;
+	}
+
+	ret = alloc_cpumask_var(&new_mask, GFP_KERNEL);
+	if (!ret)
+		goto skip_cpumask_set;
+
+	ret = bitmap_parse(arg, strlen(arg), cpumask_bits(new_mask),
+			   nr_cpumask_bits);
+	if (ret)
+		goto free_cpumask_set;
+
+	if (cpumask_empty(new_mask) || check_invalid(new_mask, max_idle)) {
+		ret = -EINVAL;
+		goto free_cpumask_set;
+	}
+
+	/*
+	 * When module parameters are passed from kernel command line
+	 * during insmod, the module parameter callback is called
+	 * before powerclamp_init(), so we can't assume that some
+	 * cpumask can be allocated and copied before here. Also
+	 * in this case this cpumask is used as the default mask.
+	 */
+	ret = allocate_copy_idle_injection_mask(new_mask);
+
+free_cpumask_set:
+	free_cpumask_var(new_mask);
+skip_cpumask_set:
+	mutex_unlock(&powerclamp_lock);
+
+	return ret;
+}
+
+static int cpumask_get(char *buf, const struct kernel_param *kp)
+{
+	if (!cpumask_available(idle_injection_cpu_mask))
+		return -ENODEV;
+
+	return bitmap_print_to_pagebuf(false, buf, cpumask_bits(idle_injection_cpu_mask),
+				       nr_cpumask_bits);
+}
+
+static const struct kernel_param_ops cpumask_ops = {
+	.set = cpumask_set,
+	.get = cpumask_get,
+};
+
+module_param_cb(cpumask, &cpumask_ops, NULL, 0644);
+MODULE_PARM_DESC(cpumask, "Mask of CPUs to use for idle injection.");
+
+static int max_idle_set(const char *arg, const struct kernel_param *kp)
+{
+	u8 new_max_idle;
+	int ret = 0;
+
+	mutex_lock(&powerclamp_lock);
+
+	/* Can't set mask when cooling device is in use */
+	if (powerclamp_data.clamping) {
+		ret = -EAGAIN;
+		goto skip_limit_set;
+	}
+
+	ret = kstrtou8(arg, 10, &new_max_idle);
+	if (ret)
+		goto skip_limit_set;
+
+	if (new_max_idle > MAX_TARGET_RATIO) {
+		ret = -EINVAL;
+		goto skip_limit_set;
+	}
+
+	if (!cpumask_available(idle_injection_cpu_mask)) {
+		ret = allocate_copy_idle_injection_mask(cpu_present_mask);
+		if (ret)
+			goto skip_limit_set;
+	}
+
+	if (check_invalid(idle_injection_cpu_mask, new_max_idle)) {
+		ret = -EINVAL;
+		goto skip_limit_set;
+	}
+
+	max_idle = new_max_idle;
+
+skip_limit_set:
+	mutex_unlock(&powerclamp_lock);
+
+	return ret;
+}
+
+static const struct kernel_param_ops max_idle_ops = {
+	.set = max_idle_set,
+	.get = param_get_byte,
+};
+
+module_param_cb(max_idle, &max_idle_ops, &max_idle, 0644);
+MODULE_PARM_DESC(max_idle, "maximum injected idle time to the total CPU time ratio in percent range:1-100");
+
+struct powerclamp_calibration_data {
+	unsigned long confidence;  /* used for calibration, basically a counter
+				    * gets incremented each time a clamping
+				    * period is completed without extra wakeups
+				    * once that counter is reached given level,
+				    * compensation is deemed usable.
+				    */
+	unsigned long steady_comp; /* steady state compensation used when
+				    * no extra wakeups occurred.
+				    */
+	unsigned long dynamic_comp; /* compensate excessive wakeup from idle
+				     * mostly from external interrupts.
+				     */
+};
+
+static struct powerclamp_calibration_data cal_data[MAX_TARGET_RATIO];
+
+static int window_size_set(const char *arg, const struct kernel_param *kp)
+{
+	int ret = 0;
+	unsigned long new_window_size;
+
+	ret = kstrtoul(arg, 10, &new_window_size);
+	if (ret)
+		goto exit_win;
+	if (new_window_size > 10 || new_window_size < 2) {
+		pr_err("Out of recommended window size %lu, between 2-10\n",
+			new_window_size);
+		ret = -EINVAL;
+	}
+
+	window_size = clamp(new_window_size, 2ul, 10ul);
+	smp_mb();
+
+exit_win:
+
+	return ret;
+}
+
+static const struct kernel_param_ops window_size_ops = {
+	.set = window_size_set,
+	.get = param_get_int,
+};
+
+module_param_cb(window_size, &window_size_ops, &window_size, 0644);
+MODULE_PARM_DESC(window_size, "sliding window in number of clamping cycles\n"
+	"\tpowerclamp controls idle ratio within this window. larger\n"
+	"\twindow size results in slower response time but more smooth\n"
+	"\tclamping results. default to 2.");
+
+static void find_target_mwait(void)
+{
+	unsigned int eax, ebx, ecx, edx;
+	unsigned int highest_cstate = 0;
+	unsigned int highest_subcstate = 0;
+	int i;
+
+	if (boot_cpu_data.cpuid_level < CPUID_MWAIT_LEAF)
+		return;
+
+	cpuid(CPUID_MWAIT_LEAF, &eax, &ebx, &ecx, &edx);
+
+	if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED) ||
+	    !(ecx & CPUID5_ECX_INTERRUPT_BREAK))
+		return;
+
+	edx >>= MWAIT_SUBSTATE_SIZE;
+	for (i = 0; i < 7 && edx; i++, edx >>= MWAIT_SUBSTATE_SIZE) {
+		if (edx & MWAIT_SUBSTATE_MASK) {
+			highest_cstate = i;
+			highest_subcstate = edx & MWAIT_SUBSTATE_MASK;
+		}
+	}
+	target_mwait = (highest_cstate << MWAIT_SUBSTATE_SIZE) |
+		(highest_subcstate - 1);
+
+}
+
+struct pkg_cstate_info {
+	bool skip;
+	int msr_index;
+	int cstate_id;
+};
+
+#define PKG_CSTATE_INIT(id) {				\
+		.msr_index = MSR_PKG_C##id##_RESIDENCY, \
+		.cstate_id = id				\
+			}
+
+static struct pkg_cstate_info pkg_cstates[] = {
+	PKG_CSTATE_INIT(2),
+	PKG_CSTATE_INIT(3),
+	PKG_CSTATE_INIT(6),
+	PKG_CSTATE_INIT(7),
+	PKG_CSTATE_INIT(8),
+	PKG_CSTATE_INIT(9),
+	PKG_CSTATE_INIT(10),
+	{NULL},
+};
+
+static bool has_pkg_state_counter(void)
+{
+	u64 val;
+	struct pkg_cstate_info *info = pkg_cstates;
+
+	/* check if any one of the counter msrs exists */
+	while (info->msr_index) {
+		if (!rdmsrl_safe(info->msr_index, &val))
+			return true;
+		info++;
+	}
+
+	return false;
+}
+
+static u64 pkg_state_counter(void)
+{
+	u64 val;
+	u64 count = 0;
+	struct pkg_cstate_info *info = pkg_cstates;
+
+	while (info->msr_index) {
+		if (!info->skip) {
+			if (!rdmsrl_safe(info->msr_index, &val))
+				count += val;
+			else
+				info->skip = true;
+		}
+		info++;
+	}
+
+	return count;
+}
+
+static unsigned int get_compensation(int ratio)
+{
+	unsigned int comp = 0;
+
+	if (!poll_pkg_cstate_enable)
+		return 0;
+
+	/* we only use compensation if all adjacent ones are good */
+	if (ratio == 1 &&
+		cal_data[ratio].confidence >= CONFIDENCE_OK &&
+		cal_data[ratio + 1].confidence >= CONFIDENCE_OK &&
+		cal_data[ratio + 2].confidence >= CONFIDENCE_OK) {
+		comp = (cal_data[ratio].steady_comp +
+			cal_data[ratio + 1].steady_comp +
+			cal_data[ratio + 2].steady_comp) / 3;
+	} else if (ratio == MAX_TARGET_RATIO - 1 &&
+		cal_data[ratio].confidence >= CONFIDENCE_OK &&
+		cal_data[ratio - 1].confidence >= CONFIDENCE_OK &&
+		cal_data[ratio - 2].confidence >= CONFIDENCE_OK) {
+		comp = (cal_data[ratio].steady_comp +
+			cal_data[ratio - 1].steady_comp +
+			cal_data[ratio - 2].steady_comp) / 3;
+	} else if (cal_data[ratio].confidence >= CONFIDENCE_OK &&
+		cal_data[ratio - 1].confidence >= CONFIDENCE_OK &&
+		cal_data[ratio + 1].confidence >= CONFIDENCE_OK) {
+		comp = (cal_data[ratio].steady_comp +
+			cal_data[ratio - 1].steady_comp +
+			cal_data[ratio + 1].steady_comp) / 3;
+	}
+
+	/* do not exceed limit */
+	if (comp + ratio >= MAX_TARGET_RATIO)
+		comp = MAX_TARGET_RATIO - ratio - 1;
+
+	return comp;
+}
+
+static void adjust_compensation(int target_ratio, unsigned int win)
+{
+	int delta;
+	struct powerclamp_calibration_data *d = &cal_data[target_ratio];
+
+	/*
+	 * adjust compensations if confidence level has not been reached.
+	 */
+	if (d->confidence >= CONFIDENCE_OK)
+		return;
+
+	delta = powerclamp_data.target_ratio - current_ratio;
+	/* filter out bad data */
+	if (delta >= 0 && delta <= (1+target_ratio/10)) {
+		if (d->steady_comp)
+			d->steady_comp =
+				roundup(delta+d->steady_comp, 2)/2;
+		else
+			d->steady_comp = delta;
+		d->confidence++;
+	}
+}
+
+static bool powerclamp_adjust_controls(unsigned int target_ratio,
+				unsigned int guard, unsigned int win)
+{
+	static u64 msr_last, tsc_last;
+	u64 msr_now, tsc_now;
+	u64 val64;
+
+	/* check result for the last window */
+	msr_now = pkg_state_counter();
+	tsc_now = rdtsc();
+
+	/* calculate pkg cstate vs tsc ratio */
+	if (!msr_last || !tsc_last)
+		current_ratio = 1;
+	else if (tsc_now-tsc_last) {
+		val64 = 100*(msr_now-msr_last);
+		do_div(val64, (tsc_now-tsc_last));
+		current_ratio = val64;
+	}
+
+	/* update record */
+	msr_last = msr_now;
+	tsc_last = tsc_now;
+
+	adjust_compensation(target_ratio, win);
+
+	/* if we are above target+guard, skip */
+	return powerclamp_data.target_ratio + guard <= current_ratio;
+}
+
+/*
+ * This function calculates runtime from the current target ratio.
+ * This function gets called under powerclamp_lock.
+ */
+static unsigned int get_run_time(void)
+{
+	unsigned int compensated_ratio;
+	unsigned int runtime;
+
+	/*
+	 * make sure user selected ratio does not take effect until
+	 * the next round. adjust target_ratio if user has changed
+	 * target such that we can converge quickly.
+	 */
+	powerclamp_data.guard = 1 + powerclamp_data.target_ratio / 20;
+	powerclamp_data.window_size_now = window_size;
+
+	/*
+	 * systems may have different ability to enter package level
+	 * c-states, thus we need to compensate the injected idle ratio
+	 * to achieve the actual target reported by the HW.
+	 */
+	compensated_ratio = powerclamp_data.target_ratio +
+		get_compensation(powerclamp_data.target_ratio);
+	if (compensated_ratio <= 0)
+		compensated_ratio = 1;
+
+	runtime = duration * 100 / compensated_ratio - duration;
+
+	return runtime;
+}
+
+/*
+ * 1 HZ polling while clamping is active, useful for userspace
+ * to monitor actual idle ratio.
+ */
+static void poll_pkg_cstate(struct work_struct *dummy);
+static DECLARE_DELAYED_WORK(poll_pkg_cstate_work, poll_pkg_cstate);
+static void poll_pkg_cstate(struct work_struct *dummy)
+{
+	static u64 msr_last;
+	static u64 tsc_last;
+
+	u64 msr_now;
+	u64 tsc_now;
+	u64 val64;
+
+	msr_now = pkg_state_counter();
+	tsc_now = rdtsc();
+
+	/* calculate pkg cstate vs tsc ratio */
+	if (!msr_last || !tsc_last)
+		pkg_cstate_ratio_cur = 1;
+	else {
+		if (tsc_now - tsc_last) {
+			val64 = 100 * (msr_now - msr_last);
+			do_div(val64, (tsc_now - tsc_last));
+			pkg_cstate_ratio_cur = val64;
+		}
+	}
+
+	/* update record */
+	msr_last = msr_now;
+	tsc_last = tsc_now;
+
+	mutex_lock(&powerclamp_lock);
+	if (powerclamp_data.clamping)
+		schedule_delayed_work(&poll_pkg_cstate_work, HZ);
+	mutex_unlock(&powerclamp_lock);
+}
+
+static struct idle_inject_device *ii_dev;
+
+/*
+ * This function is called from idle injection core on timer expiry
+ * for the run duration. This allows powerclamp to readjust or skip
+ * injecting idle for this cycle.
+ */
+static bool idle_inject_update(void)
+{
+	bool update = false;
+
+	/* We can't sleep in this callback */
+	if (!mutex_trylock(&powerclamp_lock))
+		return true;
+
+	if (!(powerclamp_data.count % powerclamp_data.window_size_now)) {
+
+		should_skip = powerclamp_adjust_controls(powerclamp_data.target_ratio,
+							 powerclamp_data.guard,
+							 powerclamp_data.window_size_now);
+		update = true;
+	}
+
+	if (update) {
+		unsigned int runtime = get_run_time();
+
+		idle_inject_set_duration(ii_dev, runtime, duration);
+	}
+
+	powerclamp_data.count++;
+
+	mutex_unlock(&powerclamp_lock);
+
+	if (should_skip)
+		return false;
+
+	return true;
+}
+
+/* This function starts idle injection by calling idle_inject_start() */
+static void trigger_idle_injection(void)
+{
+	unsigned int runtime = get_run_time();
+
+	idle_inject_set_duration(ii_dev, runtime, duration);
+	idle_inject_start(ii_dev);
+	powerclamp_data.clamping = true;
+}
+
+/*
+ * This function is called from start_power_clamp() to register
+ * CPUS with powercap idle injection register and set default
+ * idle duration and latency.
+ */
+static int powerclamp_idle_injection_register(void)
+{
+	poll_pkg_cstate_enable = false;
+	if (cpumask_equal(cpu_present_mask, idle_injection_cpu_mask)) {
+		ii_dev = idle_inject_register_full(idle_injection_cpu_mask, idle_inject_update);
+		if (topology_max_packages() == 1 && topology_max_die_per_package() == 1)
+			poll_pkg_cstate_enable = true;
+	} else {
+		ii_dev = idle_inject_register(idle_injection_cpu_mask);
+	}
+
+	if (!ii_dev) {
+		pr_err("powerclamp: idle_inject_register failed\n");
+		return -EAGAIN;
+	}
+
+	idle_inject_set_duration(ii_dev, TICK_USEC, duration);
+	idle_inject_set_latency(ii_dev, UINT_MAX);
+
+	return 0;
+}
+
+/*
+ * This function is called from end_power_clamp() to stop idle injection
+ * and unregister CPUS from powercap idle injection core.
+ */
+static void remove_idle_injection(void)
+{
+	if (!powerclamp_data.clamping)
+		return;
+
+	powerclamp_data.clamping = false;
+	idle_inject_stop(ii_dev);
+}
+
+/*
+ * This function is called when user change the cooling device
+ * state from zero to some other value.
+ */
+static int start_power_clamp(void)
+{
+	int ret;
+
+	ret = powerclamp_idle_injection_register();
+	if (!ret) {
+		trigger_idle_injection();
+		if (poll_pkg_cstate_enable)
+			schedule_delayed_work(&poll_pkg_cstate_work, 0);
+	}
+
+	return ret;
+}
+
+/*
+ * This function is called when user change the cooling device
+ * state from non zero value zero.
+ */
+static void end_power_clamp(void)
+{
+	if (powerclamp_data.clamping) {
+		remove_idle_injection();
+		idle_inject_unregister(ii_dev);
+	}
+}
+
+static int powerclamp_get_max_state(struct thermal_cooling_device *cdev,
+				 unsigned long *state)
+{
+	*state = MAX_TARGET_RATIO;
+
+	return 0;
+}
+
+static int powerclamp_get_cur_state(struct thermal_cooling_device *cdev,
+				 unsigned long *state)
+{
+	mutex_lock(&powerclamp_lock);
+	*state = powerclamp_data.target_ratio;
+	mutex_unlock(&powerclamp_lock);
+
+	return 0;
+}
+
+static int powerclamp_set_cur_state(struct thermal_cooling_device *cdev,
+				 unsigned long new_target_ratio)
+{
+	int ret = 0;
+
+	mutex_lock(&powerclamp_lock);
+
+	new_target_ratio = clamp(new_target_ratio, 0UL,
+				(unsigned long) (max_idle - 1));
+
+	if (powerclamp_data.target_ratio == new_target_ratio)
+		goto exit_set;
+
+	if (!powerclamp_data.target_ratio && new_target_ratio > 0) {
+		pr_info("Start idle injection to reduce power\n");
+		powerclamp_data.target_ratio = new_target_ratio;
+		ret = start_power_clamp();
+		if (ret)
+			powerclamp_data.target_ratio = 0;
+		goto exit_set;
+	} else	if (powerclamp_data.target_ratio > 0 && new_target_ratio == 0) {
+		pr_info("Stop forced idle injection\n");
+		end_power_clamp();
+		powerclamp_data.target_ratio = 0;
+	} else	/* adjust currently running */ {
+		unsigned int runtime;
+
+		powerclamp_data.target_ratio = new_target_ratio;
+		runtime = get_run_time();
+		idle_inject_set_duration(ii_dev, runtime, duration);
+	}
+
+exit_set:
+	mutex_unlock(&powerclamp_lock);
+
+	return ret;
+}
+
+/* bind to generic thermal layer as cooling device*/
+static const struct thermal_cooling_device_ops powerclamp_cooling_ops = {
+	.get_max_state = powerclamp_get_max_state,
+	.get_cur_state = powerclamp_get_cur_state,
+	.set_cur_state = powerclamp_set_cur_state,
+};
+
+static const struct x86_cpu_id __initconst intel_powerclamp_ids[] = {
+	X86_MATCH_VENDOR_FEATURE(INTEL, X86_FEATURE_MWAIT, NULL),
+	{}
+};
+MODULE_DEVICE_TABLE(x86cpu, intel_powerclamp_ids);
+
+static int __init powerclamp_probe(void)
+{
+
+	if (!x86_match_cpu(intel_powerclamp_ids)) {
+		pr_err("CPU does not support MWAIT\n");
+		return -ENODEV;
+	}
+
+	/* The goal for idle time alignment is to achieve package cstate. */
+	if (!has_pkg_state_counter()) {
+		pr_info("No package C-state available\n");
+		return -ENODEV;
+	}
+
+	/* find the deepest mwait value */
+	find_target_mwait();
+
+	return 0;
+}
+
+static int powerclamp_debug_show(struct seq_file *m, void *unused)
+{
+	int i = 0;
+
+	seq_printf(m, "pct confidence steady dynamic (compensation)\n");
+	for (i = 0; i < MAX_TARGET_RATIO; i++) {
+		seq_printf(m, "%d\t%lu\t%lu\t%lu\n",
+			i,
+			cal_data[i].confidence,
+			cal_data[i].steady_comp,
+			cal_data[i].dynamic_comp);
+	}
+
+	return 0;
+}
+
+DEFINE_SHOW_ATTRIBUTE(powerclamp_debug);
+
+static inline void powerclamp_create_debug_files(void)
+{
+	debug_dir = debugfs_create_dir("intel_powerclamp", NULL);
+
+	debugfs_create_file("powerclamp_calib", S_IRUGO, debug_dir, cal_data,
+			    &powerclamp_debug_fops);
+}
+
+static int __init powerclamp_init(void)
+{
+	int retval;
+
+	/* probe cpu features and ids here */
+	retval = powerclamp_probe();
+	if (retval)
+		return retval;
+
+	mutex_lock(&powerclamp_lock);
+	if (!cpumask_available(idle_injection_cpu_mask))
+		retval = allocate_copy_idle_injection_mask(cpu_present_mask);
+	mutex_unlock(&powerclamp_lock);
+
+	if (retval)
+		return retval;
+
+	/* set default limit, maybe adjusted during runtime based on feedback */
+	window_size = 2;
+
+	cooling_dev = thermal_cooling_device_register("intel_powerclamp", NULL,
+						      &powerclamp_cooling_ops);
+	if (IS_ERR(cooling_dev))
+		return -ENODEV;
+
+	if (!duration)
+		duration = jiffies_to_usecs(DEFAULT_DURATION_JIFFIES);
+
+	powerclamp_create_debug_files();
+
+	return 0;
+}
+module_init(powerclamp_init);
+
+static void __exit powerclamp_exit(void)
+{
+	mutex_lock(&powerclamp_lock);
+	end_power_clamp();
+	mutex_unlock(&powerclamp_lock);
+
+	thermal_cooling_device_unregister(cooling_dev);
+
+	cancel_delayed_work_sync(&poll_pkg_cstate_work);
+	debugfs_remove_recursive(debug_dir);
+
+	if (cpumask_available(idle_injection_cpu_mask))
+		free_cpumask_var(idle_injection_cpu_mask);
+}
+module_exit(powerclamp_exit);
+
+MODULE_IMPORT_NS(IDLE_INJECT);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Arjan van de Ven <arjan@linux.intel.com>");
+MODULE_AUTHOR("Jacob Pan <jacob.jun.pan@linux.intel.com>");
+MODULE_DESCRIPTION("Package Level C-state Idle Injection for Intel CPUs");