path: root/drivers/misc/tegra-profiler/power_clk.c

/*
 * drivers/misc/tegra-profiler/power_clk.c
 *
 * Copyright (c) 2015, NVIDIA CORPORATION.  All rights reserved.
 *
 * 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.
 *
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/cpufreq.h>
#include <linux/clk.h>
#include <linux/notifier.h>
#include <linux/cpu.h>
#include <linux/timer.h>

#include <linux/tegra_profiler.h>

#include "power_clk.h"
#include "quadd.h"
#include "hrt.h"
#include "comm.h"
#include "debug.h"

#define POWER_CLK_MAX_VALUES	32

typedef int (*notifier_call_ft)(struct notifier_block *, unsigned long, void *);

struct power_clk_data {
	unsigned long value;
	unsigned long prev;
};

struct power_clk_source {
	int type;

	struct clk *clkp;
	struct notifier_block nb;

	int nr;
	struct power_clk_data data[POWER_CLK_MAX_VALUES];

	unsigned long long counter;
	atomic_t active;

	struct mutex lock;
};

struct power_clk_context_s {
	struct power_clk_source cpu;
	struct power_clk_source gpu;
	struct power_clk_source emc;

	struct timer_list timer;
	unsigned int period;

	struct quadd_ctx *quadd_ctx;
};

enum {
	QUADD_POWER_CLK_CPU = 1,
	QUADD_POWER_CLK_GPU,
	QUADD_POWER_CLK_EMC,
};

static struct power_clk_context_s power_ctx;

static void check_clks(void);

static void read_source(struct power_clk_source *s)
{
	int i;

	mutex_lock(&s->lock);

	switch (s->type) {
	case QUADD_POWER_CLK_CPU:
		/* update cpu frequency */
		for (i = 0; i < nr_cpu_ids; i++)
			s->data[i].value = cpufreq_get(i);
		break;

	case QUADD_POWER_CLK_GPU:
		/* update gpu frequency */
		s->clkp = clk_get_sys("3d", NULL);
		if (s->clkp) {
			s->data[0].value =
				clk_get_rate(s->clkp) / 1000;
			clk_put(s->clkp);
		}
		break;

	case QUADD_POWER_CLK_EMC:
		/* update emc frequency */
		s->clkp = clk_get_sys("cpu", "emc");
		if (s->clkp) {
			s->data[0].value =
				clk_get_rate(s->clkp) / 1000;
			clk_put(s->clkp);
		}
		break;

	default:
		pr_err_once("%s: error: invalid power_clk type\n", __func__);
		return;
	}

	mutex_unlock(&s->lock);
	s->counter++;
}

static int
gpu_notifier_call(struct notifier_block *nb, unsigned long val, void *ptr)
{
	read_source(&power_ctx.gpu);
	check_clks();

	return 0;
}

static int
emc_notifier_call(struct notifier_block *nb, unsigned long val, void *ptr)
{
	read_source(&power_ctx.emc);
	check_clks();

	return 0;
}

static int
cpu_notifier_call(struct notifier_block *nb, unsigned long val, void *ptr)
{
	read_source(&power_ctx.cpu);

#ifndef CONFIG_COMMON_CLK
	read_source(&power_ctx.gpu);
	read_source(&power_ctx.emc);
#endif

	check_clks();

	return 0;
}

static void make_sample(void)
{
	int i;
	u32 extra_cpus[NR_CPUS];
	struct power_clk_source *s;
	struct quadd_iovec vec;

	struct quadd_record_data record;
	struct quadd_power_rate_data *power_rate = &record.power_rate;

	record.record_type = QUADD_RECORD_TYPE_POWER_RATE;

	power_rate->time = quadd_get_time();

	s = &power_ctx.cpu;
	mutex_lock(&s->lock);
	if (atomic_read(&s->active)) {
		power_rate->nr_cpus = s->nr;
		for (i = 0; i < s->nr; i++)
			extra_cpus[i] = s->data[i].value;
	} else {
		power_rate->nr_cpus = 0;
	}
	mutex_unlock(&s->lock);

	s = &power_ctx.gpu;
	mutex_lock(&s->lock);
	if (atomic_read(&s->active))
		power_rate->gpu = s->data[0].value;
	else
		power_rate->gpu = 0;

	mutex_unlock(&s->lock);

	s = &power_ctx.emc;
	mutex_lock(&s->lock);
	if (atomic_read(&s->active))
		power_rate->emc = s->data[0].value;
	else
		power_rate->emc = 0;

	mutex_unlock(&s->lock);
/*
	pr_debug("make_sample: cpu: %u/%u/%u/%u, gpu: %u, emc: %u\n",
		 extra_cpus[0], extra_cpus[1], extra_cpus[2], extra_cpus[3],
		 power_rate->gpu, power_rate->emc);
*/
	vec.base = extra_cpus;
	vec.len = power_rate->nr_cpus * sizeof(extra_cpus[0]);

	quadd_put_sample(&record, &vec, 1);
}

static inline int is_data_changed(struct power_clk_source *s)
{
	int i;

	mutex_lock(&s->lock);
	for (i = 0; i < s->nr; i++) {
		if (s->data[i].value != s->data[i].prev) {
			mutex_unlock(&s->lock);
			return 1;
		}
	}
	mutex_unlock(&s->lock);

	return 0;
}

static inline void update_data(struct power_clk_source *s)
{
	int i;

	mutex_lock(&s->lock);

	for (i = 0; i < s->nr; i++)
		s->data[i].prev = s->data[i].value;

	mutex_unlock(&s->lock);
}

static void check_clks(void)
{
	int changed = 0;

	if (is_data_changed(&power_ctx.cpu)) {
		update_data(&power_ctx.cpu);
		changed = 1;
	}

	if (is_data_changed(&power_ctx.gpu)) {
		update_data(&power_ctx.gpu);
		changed = 1;
	}

	if (is_data_changed(&power_ctx.emc)) {
		update_data(&power_ctx.emc);
		changed = 1;
	}
/*
	pr_debug("cpu: %lu/%lu/%lu/%lu, gpu: %lu, emc: %lu, changed: %s\n",
		 power_ctx.cpu.data[0].value, power_ctx.cpu.data[1].value,
		 power_ctx.cpu.data[2].value, power_ctx.cpu.data[3].value,
		 power_ctx.gpu.data[0].value, power_ctx.emc.data[0].value,
		 changed ? "yes" : "no");
*/
	if (changed)
		make_sample();
}

static void reset_data(struct power_clk_source *s)
{
	int i;

	mutex_lock(&s->lock);
	for (i = 0; i < s->nr; i++) {
		s->data[i].value = 0;
		s->data[i].prev = 0;
	}
	atomic_set(s, 0);
	mutex_unlock(&s->lock);
}

static void init_source(struct power_clk_source *s,
			notifier_call_ft notifier,
			int nr_values,
			int type)
{
	s->type = type;
	s->nb.notifier_call = notifier;
	s->nr = nr_values;

	mutex_init(&s->lock);
	reset_data(s);
}

static void
power_clk_work_func(struct work_struct *dummy)
{
#ifndef CONFIG_COMMON_CLK
	read_source(&power_ctx.gpu);
	read_source(&power_ctx.emc);

	check_clks();
#endif
}

static DECLARE_WORK(power_clk_work, power_clk_work_func);

static void power_clk_timer(unsigned long data)
{
	struct timer_list *timer = &power_ctx.timer;

	schedule_work(&power_clk_work);
	timer->expires = jiffies + msecs_to_jiffies(power_ctx.period);
	add_timer(timer);
}

int quadd_power_clk_start(void)
{
	struct power_clk_source *s;
	int status;
	struct timer_list *timer = &power_ctx.timer;
	struct quadd_parameters *param = &power_ctx.quadd_ctx->param;

	if (param->power_rate_freq == 0) {
		pr_info("power_clk is not started\n");
		return 0;
	}

#ifdef CONFIG_COMMON_CLK
	power_ctx.period = 0;
#else
	power_ctx.period = MSEC_PER_SEC / param->power_rate_freq;
#endif
	pr_info("power_clk: start, freq: %d\n",
		param->power_rate_freq);

	/* setup gpu frequency */
	s = &power_ctx.gpu;
	s->clkp = clk_get_sys("3d", NULL);
	if (s->clkp) {
#ifdef CONFIG_COMMON_CLK
		status = clk_notifier_register(s->clkp, s->nb);
		if (status < 0) {
			pr_err("error: could not setup gpu freq\n");
			return status;
		}
		clk_put(s->clkp);
#endif
		reset_data(s);
		atomic_set(&s->active, 1);
	} else {
		pr_err("error: could not setup gpu freq\n");
		atomic_set(&s->active, 0);
	}

	/* setup emc frequency */
	s = &power_ctx.emc;
	s->clkp = clk_get_sys("cpu", "emc");
	if (s->clkp) {
#ifdef CONFIG_COMMON_CLK
		status = clk_notifier_register(s->clkp, s->nb);
		if (status < 0) {
			pr_err("error: could not setup emc freq\n");
			return status;
		}
		clk_put(s->clkp);
#endif
		reset_data(s);
		atomic_set(&s->active, 1);
	} else {
		pr_err("error: could not setup emc freq\n");
		atomic_set(&s->active, 0);
	}

	/* setup cpu frequency notifier */
	s = &power_ctx.cpu;
	status = register_cpu_notifier(&s->nb);
	if (status < 0) {
		pr_err("error: could not setup cpu freq\n");
		return status;
	}
	reset_data(s);

	if (power_ctx.period > 0) {
		init_timer(timer);
		timer->function = power_clk_timer;
		timer->expires = jiffies + msecs_to_jiffies(power_ctx.period);
		timer->data = 0;
		add_timer(timer);
	}

	atomic_set(&s->active, 1);

	return 0;
}

void quadd_power_clk_stop(void)
{
	struct power_clk_source *s;

	if (power_ctx.quadd_ctx->param.power_rate_freq == 0)
		return;

	if (power_ctx.period > 0)
		del_timer_sync(&power_ctx.timer);

	s = &power_ctx.gpu;
	if (atomic_cmpxchg(&s->active, 1, 0)) {
#ifdef CONFIG_COMMON_CLK
		if (s->clkp)
			clk_notifier_unregister(s->clkp, &s->nb);
#endif
	}

	s = &power_ctx.emc;
	if (atomic_cmpxchg(&s->active, 1, 0)) {
#ifdef CONFIG_COMMON_CLK
		if (s->clkp)
			clk_notifier_unregister(s->clkp, &s->nb);
#endif
	}

	s = &power_ctx.cpu;
	if (atomic_cmpxchg(&s->active, 1, 0)) {
		pr_info("power_clk: stop\n");
		unregister_cpu_notifier(&s->nb);
	}
}

int quadd_power_clk_init(struct quadd_ctx *quadd_ctx)
{
	pr_info("power_clk: init\n");

	init_source(&power_ctx.cpu, cpu_notifier_call, nr_cpu_ids,
		    QUADD_POWER_CLK_CPU);
	init_source(&power_ctx.gpu, gpu_notifier_call, 1, QUADD_POWER_CLK_GPU);
	init_source(&power_ctx.emc, emc_notifier_call, 1, QUADD_POWER_CLK_EMC);

	power_ctx.quadd_ctx = quadd_ctx;

	return 0;
}

void quadd_power_clk_deinit(void)
{
	pr_info("power_clk: deinit\n");
	quadd_power_clk_stop();
}