blob: 10661eb2aed8700e9f9375de9e998431b3e86719 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0-only
/*
* A devfreq driver for NVIDIA Tegra SoCs
*
* Copyright (c) 2014 NVIDIA CORPORATION. All rights reserved.
* Copyright (C) 2014 Google, Inc
*/
#include <linux/clk.h>
#include <linux/cpufreq.h>
#include <linux/devfreq.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/pm_opp.h>
#include <linux/reset.h>
#include <linux/workqueue.h>
#include <soc/tegra/fuse.h>
#include "governor.h"
#define ACTMON_GLB_STATUS 0x0
#define ACTMON_GLB_PERIOD_CTRL 0x4
#define ACTMON_DEV_CTRL 0x0
#define ACTMON_DEV_CTRL_K_VAL_SHIFT 10
#define ACTMON_DEV_CTRL_ENB_PERIODIC BIT(18)
#define ACTMON_DEV_CTRL_AVG_BELOW_WMARK_EN BIT(20)
#define ACTMON_DEV_CTRL_AVG_ABOVE_WMARK_EN BIT(21)
#define ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_NUM_SHIFT 23
#define ACTMON_DEV_CTRL_CONSECUTIVE_ABOVE_WMARK_NUM_SHIFT 26
#define ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN BIT(29)
#define ACTMON_DEV_CTRL_CONSECUTIVE_ABOVE_WMARK_EN BIT(30)
#define ACTMON_DEV_CTRL_ENB BIT(31)
#define ACTMON_DEV_CTRL_STOP 0x00000000
#define ACTMON_DEV_UPPER_WMARK 0x4
#define ACTMON_DEV_LOWER_WMARK 0x8
#define ACTMON_DEV_INIT_AVG 0xc
#define ACTMON_DEV_AVG_UPPER_WMARK 0x10
#define ACTMON_DEV_AVG_LOWER_WMARK 0x14
#define ACTMON_DEV_COUNT_WEIGHT 0x18
#define ACTMON_DEV_AVG_COUNT 0x20
#define ACTMON_DEV_INTR_STATUS 0x24
#define ACTMON_INTR_STATUS_CLEAR 0xffffffff
#define ACTMON_DEV_INTR_CONSECUTIVE_UPPER BIT(31)
#define ACTMON_DEV_INTR_CONSECUTIVE_LOWER BIT(30)
#define ACTMON_ABOVE_WMARK_WINDOW 1
#define ACTMON_BELOW_WMARK_WINDOW 3
#define ACTMON_BOOST_FREQ_STEP 16000
/*
* ACTMON_AVERAGE_WINDOW_LOG2: default value for @DEV_CTRL_K_VAL, which
* translates to 2 ^ (K_VAL + 1). ex: 2 ^ (6 + 1) = 128
*/
#define ACTMON_AVERAGE_WINDOW_LOG2 6
#define ACTMON_SAMPLING_PERIOD 12 /* ms */
#define ACTMON_DEFAULT_AVG_BAND 6 /* 1/10 of % */
#define KHZ 1000
#define KHZ_MAX (ULONG_MAX / KHZ)
/* Assume that the bus is saturated if the utilization is 25% */
#define BUS_SATURATION_RATIO 25
/**
* struct tegra_devfreq_device_config - configuration specific to an ACTMON
* device
*
* Coefficients and thresholds are percentages unless otherwise noted
*/
struct tegra_devfreq_device_config {
u32 offset;
u32 irq_mask;
/* Factors applied to boost_freq every consecutive watermark breach */
unsigned int boost_up_coeff;
unsigned int boost_down_coeff;
/* Define the watermark bounds when applied to the current avg */
unsigned int boost_up_threshold;
unsigned int boost_down_threshold;
/*
* Threshold of activity (cycles translated to kHz) below which the
* CPU frequency isn't to be taken into account. This is to avoid
* increasing the EMC frequency when the CPU is very busy but not
* accessing the bus often.
*/
u32 avg_dependency_threshold;
};
enum tegra_actmon_device {
MCALL = 0,
MCCPU,
};
static const struct tegra_devfreq_device_config tegra124_device_configs[] = {
{
/* MCALL: All memory accesses (including from the CPUs) */
.offset = 0x1c0,
.irq_mask = 1 << 26,
.boost_up_coeff = 200,
.boost_down_coeff = 50,
.boost_up_threshold = 60,
.boost_down_threshold = 40,
},
{
/* MCCPU: memory accesses from the CPUs */
.offset = 0x200,
.irq_mask = 1 << 25,
.boost_up_coeff = 800,
.boost_down_coeff = 40,
.boost_up_threshold = 27,
.boost_down_threshold = 10,
.avg_dependency_threshold = 16000, /* 16MHz in kHz units */
},
};
static const struct tegra_devfreq_device_config tegra30_device_configs[] = {
{
/* MCALL: All memory accesses (including from the CPUs) */
.offset = 0x1c0,
.irq_mask = 1 << 26,
.boost_up_coeff = 200,
.boost_down_coeff = 50,
.boost_up_threshold = 20,
.boost_down_threshold = 10,
},
{
/* MCCPU: memory accesses from the CPUs */
.offset = 0x200,
.irq_mask = 1 << 25,
.boost_up_coeff = 800,
.boost_down_coeff = 40,
.boost_up_threshold = 27,
.boost_down_threshold = 10,
.avg_dependency_threshold = 16000, /* 16MHz in kHz units */
},
};
/**
* struct tegra_devfreq_device - state specific to an ACTMON device
*
* Frequencies are in kHz.
*/
struct tegra_devfreq_device {
const struct tegra_devfreq_device_config *config;
void __iomem *regs;
/* Average event count sampled in the last interrupt */
u32 avg_count;
/*
* Extra frequency to increase the target by due to consecutive
* watermark breaches.
*/
unsigned long boost_freq;
/* Optimal frequency calculated from the stats for this device */
unsigned long target_freq;
};
struct tegra_devfreq_soc_data {
const struct tegra_devfreq_device_config *configs;
/* Weight value for count measurements */
unsigned int count_weight;
};
struct tegra_devfreq {
struct devfreq *devfreq;
struct opp_table *opp_table;
struct reset_control *reset;
struct clk *clock;
void __iomem *regs;
struct clk *emc_clock;
unsigned long max_freq;
unsigned long cur_freq;
struct notifier_block clk_rate_change_nb;
struct delayed_work cpufreq_update_work;
struct notifier_block cpu_rate_change_nb;
struct tegra_devfreq_device devices[2];
unsigned int irq;
bool started;
const struct tegra_devfreq_soc_data *soc;
};
struct tegra_actmon_emc_ratio {
unsigned long cpu_freq;
unsigned long emc_freq;
};
static const struct tegra_actmon_emc_ratio actmon_emc_ratios[] = {
{ 1400000, KHZ_MAX },
{ 1200000, 750000 },
{ 1100000, 600000 },
{ 1000000, 500000 },
{ 800000, 375000 },
{ 500000, 200000 },
{ 250000, 100000 },
};
static u32 actmon_readl(struct tegra_devfreq *tegra, u32 offset)
{
return readl_relaxed(tegra->regs + offset);
}
static void actmon_writel(struct tegra_devfreq *tegra, u32 val, u32 offset)
{
writel_relaxed(val, tegra->regs + offset);
}
static u32 device_readl(struct tegra_devfreq_device *dev, u32 offset)
{
return readl_relaxed(dev->regs + offset);
}
static void device_writel(struct tegra_devfreq_device *dev, u32 val,
u32 offset)
{
writel_relaxed(val, dev->regs + offset);
}
static unsigned long do_percent(unsigned long long val, unsigned int pct)
{
val = val * pct;
do_div(val, 100);
/*
* High freq + high boosting percent + large polling interval are
* resulting in integer overflow when watermarks are calculated.
*/
return min_t(u64, val, U32_MAX);
}
static void tegra_devfreq_update_avg_wmark(struct tegra_devfreq *tegra,
struct tegra_devfreq_device *dev)
{
u32 avg_band_freq = tegra->max_freq * ACTMON_DEFAULT_AVG_BAND / KHZ;
u32 band = avg_band_freq * tegra->devfreq->profile->polling_ms;
u32 avg;
avg = min(dev->avg_count, U32_MAX - band);
device_writel(dev, avg + band, ACTMON_DEV_AVG_UPPER_WMARK);
avg = max(dev->avg_count, band);
device_writel(dev, avg - band, ACTMON_DEV_AVG_LOWER_WMARK);
}
static void tegra_devfreq_update_wmark(struct tegra_devfreq *tegra,
struct tegra_devfreq_device *dev)
{
u32 val = tegra->cur_freq * tegra->devfreq->profile->polling_ms;
device_writel(dev, do_percent(val, dev->config->boost_up_threshold),
ACTMON_DEV_UPPER_WMARK);
device_writel(dev, do_percent(val, dev->config->boost_down_threshold),
ACTMON_DEV_LOWER_WMARK);
}
static void actmon_isr_device(struct tegra_devfreq *tegra,
struct tegra_devfreq_device *dev)
{
u32 intr_status, dev_ctrl;
dev->avg_count = device_readl(dev, ACTMON_DEV_AVG_COUNT);
tegra_devfreq_update_avg_wmark(tegra, dev);
intr_status = device_readl(dev, ACTMON_DEV_INTR_STATUS);
dev_ctrl = device_readl(dev, ACTMON_DEV_CTRL);
if (intr_status & ACTMON_DEV_INTR_CONSECUTIVE_UPPER) {
/*
* new_boost = min(old_boost * up_coef + step, max_freq)
*/
dev->boost_freq = do_percent(dev->boost_freq,
dev->config->boost_up_coeff);
dev->boost_freq += ACTMON_BOOST_FREQ_STEP;
dev_ctrl |= ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN;
if (dev->boost_freq >= tegra->max_freq) {
dev_ctrl &= ~ACTMON_DEV_CTRL_CONSECUTIVE_ABOVE_WMARK_EN;
dev->boost_freq = tegra->max_freq;
}
} else if (intr_status & ACTMON_DEV_INTR_CONSECUTIVE_LOWER) {
/*
* new_boost = old_boost * down_coef
* or 0 if (old_boost * down_coef < step / 2)
*/
dev->boost_freq = do_percent(dev->boost_freq,
dev->config->boost_down_coeff);
dev_ctrl |= ACTMON_DEV_CTRL_CONSECUTIVE_ABOVE_WMARK_EN;
if (dev->boost_freq < (ACTMON_BOOST_FREQ_STEP >> 1)) {
dev_ctrl &= ~ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN;
dev->boost_freq = 0;
}
}
device_writel(dev, dev_ctrl, ACTMON_DEV_CTRL);
device_writel(dev, ACTMON_INTR_STATUS_CLEAR, ACTMON_DEV_INTR_STATUS);
}
static unsigned long actmon_cpu_to_emc_rate(struct tegra_devfreq *tegra,
unsigned long cpu_freq)
{
unsigned int i;
const struct tegra_actmon_emc_ratio *ratio = actmon_emc_ratios;
for (i = 0; i < ARRAY_SIZE(actmon_emc_ratios); i++, ratio++) {
if (cpu_freq >= ratio->cpu_freq) {
if (ratio->emc_freq >= tegra->max_freq)
return tegra->max_freq;
else
return ratio->emc_freq;
}
}
return 0;
}
static unsigned long actmon_device_target_freq(struct tegra_devfreq *tegra,
struct tegra_devfreq_device *dev)
{
unsigned int avg_sustain_coef;
unsigned long target_freq;
target_freq = dev->avg_count / tegra->devfreq->profile->polling_ms;
avg_sustain_coef = 100 * 100 / dev->config->boost_up_threshold;
target_freq = do_percent(target_freq, avg_sustain_coef);
return target_freq;
}
static void actmon_update_target(struct tegra_devfreq *tegra,
struct tegra_devfreq_device *dev)
{
unsigned long cpu_freq = 0;
unsigned long static_cpu_emc_freq = 0;
dev->target_freq = actmon_device_target_freq(tegra, dev);
if (dev->config->avg_dependency_threshold &&
dev->config->avg_dependency_threshold <= dev->target_freq) {
cpu_freq = cpufreq_quick_get(0);
static_cpu_emc_freq = actmon_cpu_to_emc_rate(tegra, cpu_freq);
dev->target_freq += dev->boost_freq;
dev->target_freq = max(dev->target_freq, static_cpu_emc_freq);
} else {
dev->target_freq += dev->boost_freq;
}
}
static irqreturn_t actmon_thread_isr(int irq, void *data)
{
struct tegra_devfreq *tegra = data;
bool handled = false;
unsigned int i;
u32 val;
mutex_lock(&tegra->devfreq->lock);
val = actmon_readl(tegra, ACTMON_GLB_STATUS);
for (i = 0; i < ARRAY_SIZE(tegra->devices); i++) {
if (val & tegra->devices[i].config->irq_mask) {
actmon_isr_device(tegra, tegra->devices + i);
handled = true;
}
}
if (handled)
update_devfreq(tegra->devfreq);
mutex_unlock(&tegra->devfreq->lock);
return handled ? IRQ_HANDLED : IRQ_NONE;
}
static int tegra_actmon_clk_notify_cb(struct notifier_block *nb,
unsigned long action, void *ptr)
{
struct clk_notifier_data *data = ptr;
struct tegra_devfreq *tegra;
struct tegra_devfreq_device *dev;
unsigned int i;
if (action != POST_RATE_CHANGE)
return NOTIFY_OK;
tegra = container_of(nb, struct tegra_devfreq, clk_rate_change_nb);
tegra->cur_freq = data->new_rate / KHZ;
for (i = 0; i < ARRAY_SIZE(tegra->devices); i++) {
dev = &tegra->devices[i];
tegra_devfreq_update_wmark(tegra, dev);
}
return NOTIFY_OK;
}
static void tegra_actmon_delayed_update(struct work_struct *work)
{
struct tegra_devfreq *tegra = container_of(work, struct tegra_devfreq,
cpufreq_update_work.work);
mutex_lock(&tegra->devfreq->lock);
update_devfreq(tegra->devfreq);
mutex_unlock(&tegra->devfreq->lock);
}
static unsigned long
tegra_actmon_cpufreq_contribution(struct tegra_devfreq *tegra,
unsigned int cpu_freq)
{
struct tegra_devfreq_device *actmon_dev = &tegra->devices[MCCPU];
unsigned long static_cpu_emc_freq, dev_freq;
dev_freq = actmon_device_target_freq(tegra, actmon_dev);
/* check whether CPU's freq is taken into account at all */
if (dev_freq < actmon_dev->config->avg_dependency_threshold)
return 0;
static_cpu_emc_freq = actmon_cpu_to_emc_rate(tegra, cpu_freq);
if (dev_freq + actmon_dev->boost_freq >= static_cpu_emc_freq)
return 0;
return static_cpu_emc_freq;
}
static int tegra_actmon_cpu_notify_cb(struct notifier_block *nb,
unsigned long action, void *ptr)
{
struct cpufreq_freqs *freqs = ptr;
struct tegra_devfreq *tegra;
unsigned long old, new, delay;
if (action != CPUFREQ_POSTCHANGE)
return NOTIFY_OK;
tegra = container_of(nb, struct tegra_devfreq, cpu_rate_change_nb);
/*
* Quickly check whether CPU frequency should be taken into account
* at all, without blocking CPUFreq's core.
*/
if (mutex_trylock(&tegra->devfreq->lock)) {
old = tegra_actmon_cpufreq_contribution(tegra, freqs->old);
new = tegra_actmon_cpufreq_contribution(tegra, freqs->new);
mutex_unlock(&tegra->devfreq->lock);
/*
* If CPU's frequency shouldn't be taken into account at
* the moment, then there is no need to update the devfreq's
* state because ISR will re-check CPU's frequency on the
* next interrupt.
*/
if (old == new)
return NOTIFY_OK;
}
/*
* CPUFreq driver should support CPUFREQ_ASYNC_NOTIFICATION in order
* to allow asynchronous notifications. This means we can't block
* here for too long, otherwise CPUFreq's core will complain with a
* warning splat.
*/
delay = msecs_to_jiffies(ACTMON_SAMPLING_PERIOD);
schedule_delayed_work(&tegra->cpufreq_update_work, delay);
return NOTIFY_OK;
}
static void tegra_actmon_configure_device(struct tegra_devfreq *tegra,
struct tegra_devfreq_device *dev)
{
u32 val = 0;
/* reset boosting on governor's restart */
dev->boost_freq = 0;
dev->target_freq = tegra->cur_freq;
dev->avg_count = tegra->cur_freq * tegra->devfreq->profile->polling_ms;
device_writel(dev, dev->avg_count, ACTMON_DEV_INIT_AVG);
tegra_devfreq_update_avg_wmark(tegra, dev);
tegra_devfreq_update_wmark(tegra, dev);
device_writel(dev, tegra->soc->count_weight, ACTMON_DEV_COUNT_WEIGHT);
device_writel(dev, ACTMON_INTR_STATUS_CLEAR, ACTMON_DEV_INTR_STATUS);
val |= ACTMON_DEV_CTRL_ENB_PERIODIC;
val |= (ACTMON_AVERAGE_WINDOW_LOG2 - 1)
<< ACTMON_DEV_CTRL_K_VAL_SHIFT;
val |= (ACTMON_BELOW_WMARK_WINDOW - 1)
<< ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_NUM_SHIFT;
val |= (ACTMON_ABOVE_WMARK_WINDOW - 1)
<< ACTMON_DEV_CTRL_CONSECUTIVE_ABOVE_WMARK_NUM_SHIFT;
val |= ACTMON_DEV_CTRL_AVG_ABOVE_WMARK_EN;
val |= ACTMON_DEV_CTRL_AVG_BELOW_WMARK_EN;
val |= ACTMON_DEV_CTRL_CONSECUTIVE_ABOVE_WMARK_EN;
val |= ACTMON_DEV_CTRL_ENB;
device_writel(dev, val, ACTMON_DEV_CTRL);
}
static void tegra_actmon_stop_devices(struct tegra_devfreq *tegra)
{
struct tegra_devfreq_device *dev = tegra->devices;
unsigned int i;
for (i = 0; i < ARRAY_SIZE(tegra->devices); i++, dev++) {
device_writel(dev, ACTMON_DEV_CTRL_STOP, ACTMON_DEV_CTRL);
device_writel(dev, ACTMON_INTR_STATUS_CLEAR,
ACTMON_DEV_INTR_STATUS);
}
}
static int tegra_actmon_resume(struct tegra_devfreq *tegra)
{
unsigned int i;
int err;
if (!tegra->devfreq->profile->polling_ms || !tegra->started)
return 0;
actmon_writel(tegra, tegra->devfreq->profile->polling_ms - 1,
ACTMON_GLB_PERIOD_CTRL);
/*
* CLK notifications are needed in order to reconfigure the upper
* consecutive watermark in accordance to the actual clock rate
* to avoid unnecessary upper interrupts.
*/
err = clk_notifier_register(tegra->emc_clock,
&tegra->clk_rate_change_nb);
if (err) {
dev_err(tegra->devfreq->dev.parent,
"Failed to register rate change notifier\n");
return err;
}
tegra->cur_freq = clk_get_rate(tegra->emc_clock) / KHZ;
for (i = 0; i < ARRAY_SIZE(tegra->devices); i++)
tegra_actmon_configure_device(tegra, &tegra->devices[i]);
/*
* We are estimating CPU's memory bandwidth requirement based on
* amount of memory accesses and system's load, judging by CPU's
* frequency. We also don't want to receive events about CPU's
* frequency transaction when governor is stopped, hence notifier
* is registered dynamically.
*/
err = cpufreq_register_notifier(&tegra->cpu_rate_change_nb,
CPUFREQ_TRANSITION_NOTIFIER);
if (err) {
dev_err(tegra->devfreq->dev.parent,
"Failed to register rate change notifier: %d\n", err);
goto err_stop;
}
enable_irq(tegra->irq);
return 0;
err_stop:
tegra_actmon_stop_devices(tegra);
clk_notifier_unregister(tegra->emc_clock, &tegra->clk_rate_change_nb);
return err;
}
static int tegra_actmon_start(struct tegra_devfreq *tegra)
{
int ret = 0;
if (!tegra->started) {
tegra->started = true;
ret = tegra_actmon_resume(tegra);
if (ret)
tegra->started = false;
}
return ret;
}
static void tegra_actmon_pause(struct tegra_devfreq *tegra)
{
if (!tegra->devfreq->profile->polling_ms || !tegra->started)
return;
disable_irq(tegra->irq);
cpufreq_unregister_notifier(&tegra->cpu_rate_change_nb,
CPUFREQ_TRANSITION_NOTIFIER);
cancel_delayed_work_sync(&tegra->cpufreq_update_work);
tegra_actmon_stop_devices(tegra);
clk_notifier_unregister(tegra->emc_clock, &tegra->clk_rate_change_nb);
}
static void tegra_actmon_stop(struct tegra_devfreq *tegra)
{
tegra_actmon_pause(tegra);
tegra->started = false;
}
static int tegra_devfreq_target(struct device *dev, unsigned long *freq,
u32 flags)
{
struct dev_pm_opp *opp;
int ret;
opp = devfreq_recommended_opp(dev, freq, flags);
if (IS_ERR(opp)) {
dev_err(dev, "Failed to find opp for %lu Hz\n", *freq);
return PTR_ERR(opp);
}
ret = dev_pm_opp_set_opp(dev, opp);
dev_pm_opp_put(opp);
return ret;
}
static int tegra_devfreq_get_dev_status(struct device *dev,
struct devfreq_dev_status *stat)
{
struct tegra_devfreq *tegra = dev_get_drvdata(dev);
struct tegra_devfreq_device *actmon_dev;
unsigned long cur_freq;
cur_freq = READ_ONCE(tegra->cur_freq);
/* To be used by the tegra governor */
stat->private_data = tegra;
/* The below are to be used by the other governors */
stat->current_frequency = cur_freq * KHZ;
actmon_dev = &tegra->devices[MCALL];
/* Number of cycles spent on memory access */
stat->busy_time = device_readl(actmon_dev, ACTMON_DEV_AVG_COUNT);
/* The bus can be considered to be saturated way before 100% */
stat->busy_time *= 100 / BUS_SATURATION_RATIO;
/* Number of cycles in a sampling period */
stat->total_time = tegra->devfreq->profile->polling_ms * cur_freq;
stat->busy_time = min(stat->busy_time, stat->total_time);
return 0;
}
static struct devfreq_dev_profile tegra_devfreq_profile = {
.polling_ms = ACTMON_SAMPLING_PERIOD,
.target = tegra_devfreq_target,
.get_dev_status = tegra_devfreq_get_dev_status,
.is_cooling_device = true,
};
static int tegra_governor_get_target(struct devfreq *devfreq,
unsigned long *freq)
{
struct devfreq_dev_status *stat;
struct tegra_devfreq *tegra;
struct tegra_devfreq_device *dev;
unsigned long target_freq = 0;
unsigned int i;
int err;
err = devfreq_update_stats(devfreq);
if (err)
return err;
stat = &devfreq->last_status;
tegra = stat->private_data;
for (i = 0; i < ARRAY_SIZE(tegra->devices); i++) {
dev = &tegra->devices[i];
actmon_update_target(tegra, dev);
target_freq = max(target_freq, dev->target_freq);
}
/*
* tegra-devfreq driver operates with KHz units, while OPP table
* entries use Hz units. Hence we need to convert the units for the
* devfreq core.
*/
*freq = target_freq * KHZ;
return 0;
}
static int tegra_governor_event_handler(struct devfreq *devfreq,
unsigned int event, void *data)
{
struct tegra_devfreq *tegra = dev_get_drvdata(devfreq->dev.parent);
unsigned int *new_delay = data;
int ret = 0;
/*
* Couple devfreq-device with the governor early because it is
* needed at the moment of governor's start (used by ISR).
*/
tegra->devfreq = devfreq;
switch (event) {
case DEVFREQ_GOV_START:
devfreq_monitor_start(devfreq);
ret = tegra_actmon_start(tegra);
break;
case DEVFREQ_GOV_STOP:
tegra_actmon_stop(tegra);
devfreq_monitor_stop(devfreq);
break;
case DEVFREQ_GOV_UPDATE_INTERVAL:
/*
* ACTMON hardware supports up to 256 milliseconds for the
* sampling period.
*/
if (*new_delay > 256) {
ret = -EINVAL;
break;
}
tegra_actmon_pause(tegra);
devfreq_update_interval(devfreq, new_delay);
ret = tegra_actmon_resume(tegra);
break;
case DEVFREQ_GOV_SUSPEND:
tegra_actmon_stop(tegra);
devfreq_monitor_suspend(devfreq);
break;
case DEVFREQ_GOV_RESUME:
devfreq_monitor_resume(devfreq);
ret = tegra_actmon_start(tegra);
break;
}
return ret;
}
static struct devfreq_governor tegra_devfreq_governor = {
.name = "tegra_actmon",
.attrs = DEVFREQ_GOV_ATTR_POLLING_INTERVAL,
.flags = DEVFREQ_GOV_FLAG_IMMUTABLE
| DEVFREQ_GOV_FLAG_IRQ_DRIVEN,
.get_target_freq = tegra_governor_get_target,
.event_handler = tegra_governor_event_handler,
};
static int tegra_devfreq_probe(struct platform_device *pdev)
{
u32 hw_version = BIT(tegra_sku_info.soc_speedo_id);
struct tegra_devfreq_device *dev;
struct tegra_devfreq *tegra;
struct devfreq *devfreq;
unsigned int i;
long rate;
int err;
tegra = devm_kzalloc(&pdev->dev, sizeof(*tegra), GFP_KERNEL);
if (!tegra)
return -ENOMEM;
tegra->soc = of_device_get_match_data(&pdev->dev);
tegra->regs = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(tegra->regs))
return PTR_ERR(tegra->regs);
tegra->reset = devm_reset_control_get(&pdev->dev, "actmon");
if (IS_ERR(tegra->reset)) {
dev_err(&pdev->dev, "Failed to get reset\n");
return PTR_ERR(tegra->reset);
}
tegra->clock = devm_clk_get(&pdev->dev, "actmon");
if (IS_ERR(tegra->clock)) {
dev_err(&pdev->dev, "Failed to get actmon clock\n");
return PTR_ERR(tegra->clock);
}
tegra->emc_clock = devm_clk_get(&pdev->dev, "emc");
if (IS_ERR(tegra->emc_clock))
return dev_err_probe(&pdev->dev, PTR_ERR(tegra->emc_clock),
"Failed to get emc clock\n");
err = platform_get_irq(pdev, 0);
if (err < 0)
return err;
tegra->irq = err;
irq_set_status_flags(tegra->irq, IRQ_NOAUTOEN);
err = devm_request_threaded_irq(&pdev->dev, tegra->irq, NULL,
actmon_thread_isr, IRQF_ONESHOT,
"tegra-devfreq", tegra);
if (err) {
dev_err(&pdev->dev, "Interrupt request failed: %d\n", err);
return err;
}
tegra->opp_table = dev_pm_opp_set_supported_hw(&pdev->dev,
&hw_version, 1);
err = PTR_ERR_OR_ZERO(tegra->opp_table);
if (err) {
dev_err(&pdev->dev, "Failed to set supported HW: %d\n", err);
return err;
}
err = dev_pm_opp_of_add_table_noclk(&pdev->dev, 0);
if (err) {
dev_err(&pdev->dev, "Failed to add OPP table: %d\n", err);
goto put_hw;
}
err = clk_prepare_enable(tegra->clock);
if (err) {
dev_err(&pdev->dev,
"Failed to prepare and enable ACTMON clock\n");
goto remove_table;
}
err = reset_control_reset(tegra->reset);
if (err) {
dev_err(&pdev->dev, "Failed to reset hardware: %d\n", err);
goto disable_clk;
}
rate = clk_round_rate(tegra->emc_clock, ULONG_MAX);
if (rate < 0) {
dev_err(&pdev->dev, "Failed to round clock rate: %ld\n", rate);
err = rate;
goto disable_clk;
}
tegra->max_freq = rate / KHZ;
for (i = 0; i < ARRAY_SIZE(tegra->devices); i++) {
dev = tegra->devices + i;
dev->config = tegra->soc->configs + i;
dev->regs = tegra->regs + dev->config->offset;
}
platform_set_drvdata(pdev, tegra);
tegra->clk_rate_change_nb.notifier_call = tegra_actmon_clk_notify_cb;
tegra->cpu_rate_change_nb.notifier_call = tegra_actmon_cpu_notify_cb;
INIT_DELAYED_WORK(&tegra->cpufreq_update_work,
tegra_actmon_delayed_update);
err = devfreq_add_governor(&tegra_devfreq_governor);
if (err) {
dev_err(&pdev->dev, "Failed to add governor: %d\n", err);
goto remove_opps;
}
tegra_devfreq_profile.initial_freq = clk_get_rate(tegra->emc_clock);
devfreq = devfreq_add_device(&pdev->dev, &tegra_devfreq_profile,
"tegra_actmon", NULL);
if (IS_ERR(devfreq)) {
err = PTR_ERR(devfreq);
goto remove_governor;
}
return 0;
remove_governor:
devfreq_remove_governor(&tegra_devfreq_governor);
remove_opps:
dev_pm_opp_remove_all_dynamic(&pdev->dev);
reset_control_reset(tegra->reset);
disable_clk:
clk_disable_unprepare(tegra->clock);
remove_table:
dev_pm_opp_of_remove_table(&pdev->dev);
put_hw:
dev_pm_opp_put_supported_hw(tegra->opp_table);
return err;
}
static int tegra_devfreq_remove(struct platform_device *pdev)
{
struct tegra_devfreq *tegra = platform_get_drvdata(pdev);
devfreq_remove_device(tegra->devfreq);
devfreq_remove_governor(&tegra_devfreq_governor);
reset_control_reset(tegra->reset);
clk_disable_unprepare(tegra->clock);
dev_pm_opp_of_remove_table(&pdev->dev);
dev_pm_opp_put_supported_hw(tegra->opp_table);
return 0;
}
static const struct tegra_devfreq_soc_data tegra124_soc = {
.configs = tegra124_device_configs,
/*
* Activity counter is incremented every 256 memory transactions,
* and each transaction takes 4 EMC clocks.
*/
.count_weight = 4 * 256,
};
static const struct tegra_devfreq_soc_data tegra30_soc = {
.configs = tegra30_device_configs,
.count_weight = 2 * 256,
};
static const struct of_device_id tegra_devfreq_of_match[] = {
{ .compatible = "nvidia,tegra30-actmon", .data = &tegra30_soc, },
{ .compatible = "nvidia,tegra124-actmon", .data = &tegra124_soc, },
{ },
};
MODULE_DEVICE_TABLE(of, tegra_devfreq_of_match);
static struct platform_driver tegra_devfreq_driver = {
.probe = tegra_devfreq_probe,
.remove = tegra_devfreq_remove,
.driver = {
.name = "tegra-devfreq",
.of_match_table = tegra_devfreq_of_match,
},
};
module_platform_driver(tegra_devfreq_driver);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("Tegra devfreq driver");
MODULE_AUTHOR("Tomeu Vizoso <tomeu.vizoso@collabora.com>");