--- /dev/null
+/*
+ * A devfreq driver for NVIDIA Tegra SoCs
+ *
+ * Copyright (c) 2014 NVIDIA CORPORATION. All rights reserved.
+ * Copyright (C) 2014 Google, Inc
+ *
+ * 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, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/cpufreq.h>
+#include <linux/devfreq.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_opp.h>
+#include <linux/reset.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_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
+
+/*
+ * Activity counter is incremented every 256 memory transactions, and each
+ * transaction takes 4 EMC clocks for Tegra124; So the COUNT_WEIGHT is
+ * 4 * 256 = 1024.
+ */
+#define ACTMON_COUNT_WEIGHT 0x400
+
+/*
+ * 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
+
+/* 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) 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 struct tegra_devfreq_device_config actmon_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 = 90,
+ .boost_up_threshold = 27,
+ .boost_down_threshold = 10,
+ .avg_dependency_threshold = 50000,
+ },
+};
+
+/**
+ * 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;
+ spinlock_t lock;
+
+ /* 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 {
+ struct devfreq *devfreq;
+
+ 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 rate_change_nb;
+
+ struct tegra_devfreq_device devices[ARRAY_SIZE(actmon_device_configs)];
+};
+
+struct tegra_actmon_emc_ratio {
+ unsigned long cpu_freq;
+ unsigned long emc_freq;
+};
+
+static struct tegra_actmon_emc_ratio actmon_emc_ratios[] = {
+ { 1400000, ULONG_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(tegra->regs + offset);
+}
+
+static void actmon_writel(struct tegra_devfreq *tegra, u32 val, u32 offset)
+{
+ writel(val, tegra->regs + offset);
+}
+
+static u32 device_readl(struct tegra_devfreq_device *dev, u32 offset)
+{
+ return readl(dev->regs + offset);
+}
+
+static void device_writel(struct tegra_devfreq_device *dev, u32 val,
+ u32 offset)
+{
+ writel(val, dev->regs + offset);
+}
+
+static unsigned long do_percent(unsigned long val, unsigned int pct)
+{
+ return val * pct / 100;
+}
+
+static void tegra_devfreq_update_avg_wmark(struct tegra_devfreq *tegra,
+ struct tegra_devfreq_device *dev)
+{
+ u32 avg = dev->avg_count;
+ u32 avg_band_freq = tegra->max_freq * ACTMON_DEFAULT_AVG_BAND / KHZ;
+ u32 band = avg_band_freq * ACTMON_SAMPLING_PERIOD;
+
+ 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 * ACTMON_SAMPLING_PERIOD;
+
+ 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_write_barrier(struct tegra_devfreq *tegra)
+{
+ /* ensure the update has reached the ACTMON */
+ wmb();
+ actmon_readl(tegra, ACTMON_GLB_STATUS);
+}
+
+static void actmon_isr_device(struct tegra_devfreq *tegra,
+ struct tegra_devfreq_device *dev)
+{
+ unsigned long flags;
+ u32 intr_status, dev_ctrl;
+
+ spin_lock_irqsave(&dev->lock, flags);
+
+ 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->boost_freq = tegra->max_freq;
+ else
+ dev_ctrl |= ACTMON_DEV_CTRL_CONSECUTIVE_ABOVE_WMARK_EN;
+ } 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->boost_freq = 0;
+ else
+ dev_ctrl |= ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN;
+ }
+
+ if (dev->config->avg_dependency_threshold) {
+ if (dev->avg_count >= dev->config->avg_dependency_threshold)
+ dev_ctrl |= ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN;
+ else if (dev->boost_freq == 0)
+ dev_ctrl &= ~ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN;
+ }
+
+ device_writel(dev, dev_ctrl, ACTMON_DEV_CTRL);
+
+ device_writel(dev, ACTMON_INTR_STATUS_CLEAR, ACTMON_DEV_INTR_STATUS);
+
+ actmon_write_barrier(tegra);
+
+ spin_unlock_irqrestore(&dev->lock, flags);
+}
+
+static irqreturn_t actmon_isr(int irq, void *data)
+{
+ struct tegra_devfreq *tegra = data;
+ bool handled = false;
+ unsigned int i;
+ u32 val;
+
+ 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;
+ }
+ }
+
+ return handled ? IRQ_WAKE_THREAD : IRQ_NONE;
+}
+
+static unsigned long actmon_cpu_to_emc_rate(struct tegra_devfreq *tegra,
+ unsigned long cpu_freq)
+{
+ unsigned int i;
+ 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 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;
+ unsigned int avg_sustain_coef;
+ unsigned long flags;
+
+ if (dev->config->avg_dependency_threshold) {
+ cpu_freq = cpufreq_get(0);
+ static_cpu_emc_freq = actmon_cpu_to_emc_rate(tegra, cpu_freq);
+ }
+
+ spin_lock_irqsave(&dev->lock, flags);
+
+ dev->target_freq = dev->avg_count / ACTMON_SAMPLING_PERIOD;
+ avg_sustain_coef = 100 * 100 / dev->config->boost_up_threshold;
+ dev->target_freq = do_percent(dev->target_freq, avg_sustain_coef);
+ dev->target_freq += dev->boost_freq;
+
+ if (dev->avg_count >= dev->config->avg_dependency_threshold)
+ dev->target_freq = max(dev->target_freq, static_cpu_emc_freq);
+
+ spin_unlock_irqrestore(&dev->lock, flags);
+}
+
+static irqreturn_t actmon_thread_isr(int irq, void *data)
+{
+ struct tegra_devfreq *tegra = data;
+
+ mutex_lock(&tegra->devfreq->lock);
+ update_devfreq(tegra->devfreq);
+ mutex_unlock(&tegra->devfreq->lock);
+
+ return IRQ_HANDLED;
+}
+
+static int tegra_actmon_rate_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;
+ unsigned long flags;
+
+ if (action != POST_RATE_CHANGE)
+ return NOTIFY_OK;
+
+ tegra = container_of(nb, struct tegra_devfreq, rate_change_nb);
+
+ tegra->cur_freq = data->new_rate / KHZ;
+
+ for (i = 0; i < ARRAY_SIZE(tegra->devices); i++) {
+ dev = &tegra->devices[i];
+
+ spin_lock_irqsave(&dev->lock, flags);
+ tegra_devfreq_update_wmark(tegra, dev);
+ spin_unlock_irqrestore(&dev->lock, flags);
+ }
+
+ actmon_write_barrier(tegra);
+
+ return NOTIFY_OK;
+}
+
+static void tegra_actmon_enable_interrupts(struct tegra_devfreq *tegra)
+{
+ struct tegra_devfreq_device *dev;
+ u32 val;
+ unsigned int i;
+
+ for (i = 0; i < ARRAY_SIZE(tegra->devices); i++) {
+ dev = &tegra->devices[i];
+
+ val = device_readl(dev, ACTMON_DEV_CTRL);
+ val |= ACTMON_DEV_CTRL_AVG_ABOVE_WMARK_EN;
+ val |= ACTMON_DEV_CTRL_AVG_BELOW_WMARK_EN;
+ val |= ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN;
+ val |= ACTMON_DEV_CTRL_CONSECUTIVE_ABOVE_WMARK_EN;
+
+ device_writel(dev, val, ACTMON_DEV_CTRL);
+ }
+
+ actmon_write_barrier(tegra);
+}
+
+static void tegra_actmon_disable_interrupts(struct tegra_devfreq *tegra)
+{
+ struct tegra_devfreq_device *dev;
+ u32 val;
+ unsigned int i;
+
+ for (i = 0; i < ARRAY_SIZE(tegra->devices); i++) {
+ dev = &tegra->devices[i];
+
+ val = device_readl(dev, ACTMON_DEV_CTRL);
+ val &= ~ACTMON_DEV_CTRL_AVG_ABOVE_WMARK_EN;
+ val &= ~ACTMON_DEV_CTRL_AVG_BELOW_WMARK_EN;
+ val &= ~ACTMON_DEV_CTRL_CONSECUTIVE_BELOW_WMARK_EN;
+ val &= ~ACTMON_DEV_CTRL_CONSECUTIVE_ABOVE_WMARK_EN;
+
+ device_writel(dev, val, ACTMON_DEV_CTRL);
+ }
+
+ actmon_write_barrier(tegra);
+}
+
+static void tegra_actmon_configure_device(struct tegra_devfreq *tegra,
+ struct tegra_devfreq_device *dev)
+{
+ u32 val = 0;
+
+ dev->target_freq = tegra->cur_freq;
+
+ dev->avg_count = tegra->cur_freq * ACTMON_SAMPLING_PERIOD;
+ 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, ACTMON_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_ENB;
+
+ device_writel(dev, val, ACTMON_DEV_CTRL);
+
+ actmon_write_barrier(tegra);
+}
+
+static int tegra_devfreq_target(struct device *dev, unsigned long *freq,
+ u32 flags)
+{
+ struct tegra_devfreq *tegra = dev_get_drvdata(dev);
+ struct dev_pm_opp *opp;
+ unsigned long rate = *freq * KHZ;
+
+ rcu_read_lock();
+ opp = devfreq_recommended_opp(dev, &rate, flags);
+ if (IS_ERR(opp)) {
+ rcu_read_unlock();
+ dev_err(dev, "Failed to find opp for %lu KHz\n", *freq);
+ return PTR_ERR(opp);
+ }
+ rate = dev_pm_opp_get_freq(opp);
+ rcu_read_unlock();
+
+ clk_set_min_rate(tegra->emc_clock, rate);
+ clk_set_rate(tegra->emc_clock, 0);
+
+ return 0;
+}
+
+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;
+
+ stat->current_frequency = tegra->cur_freq;
+
+ /* To be used by the tegra governor */
+ stat->private_data = tegra;
+
+ /* The below are to be used by the other governors */
+
+ 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 = ACTMON_SAMPLING_PERIOD * tegra->cur_freq;
+
+ stat->busy_time = min(stat->busy_time, stat->total_time);
+
+ return 0;
+}
+
+static struct devfreq_dev_profile tegra_devfreq_profile = {
+ .polling_ms = 0,
+ .target = tegra_devfreq_target,
+ .get_dev_status = tegra_devfreq_get_dev_status,
+};
+
+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->profile->get_dev_status(devfreq->dev.parent, &stat);
+ if (err)
+ return err;
+
+ 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);
+ }
+
+ *freq = target_freq;
+
+ return 0;
+}
+
+static int tegra_governor_event_handler(struct devfreq *devfreq,
+ unsigned int event, void *data)
+{
+ struct tegra_devfreq *tegra;
+ int ret = 0;
+
+ tegra = dev_get_drvdata(devfreq->dev.parent);
+
+ switch (event) {
+ case DEVFREQ_GOV_START:
+ devfreq_monitor_start(devfreq);
+ tegra_actmon_enable_interrupts(tegra);
+ break;
+
+ case DEVFREQ_GOV_STOP:
+ tegra_actmon_disable_interrupts(tegra);
+ devfreq_monitor_stop(devfreq);
+ break;
+
+ case DEVFREQ_GOV_SUSPEND:
+ tegra_actmon_disable_interrupts(tegra);
+ devfreq_monitor_suspend(devfreq);
+ break;
+
+ case DEVFREQ_GOV_RESUME:
+ devfreq_monitor_resume(devfreq);
+ tegra_actmon_enable_interrupts(tegra);
+ break;
+ }
+
+ return ret;
+}
+
+static struct devfreq_governor tegra_devfreq_governor = {
+ .name = "tegra_actmon",
+ .get_target_freq = tegra_governor_get_target,
+ .event_handler = tegra_governor_event_handler,
+};
+
+static int tegra_devfreq_probe(struct platform_device *pdev)
+{
+ struct tegra_devfreq *tegra;
+ struct tegra_devfreq_device *dev;
+ struct resource *res;
+ unsigned int i;
+ unsigned long rate;
+ int irq;
+ int err;
+
+ tegra = devm_kzalloc(&pdev->dev, sizeof(*tegra), GFP_KERNEL);
+ if (!tegra)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+ tegra->regs = devm_ioremap_resource(&pdev->dev, res);
+ 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)) {
+ dev_err(&pdev->dev, "Failed to get emc clock\n");
+ return PTR_ERR(tegra->emc_clock);
+ }
+
+ clk_set_rate(tegra->emc_clock, ULONG_MAX);
+
+ tegra->rate_change_nb.notifier_call = tegra_actmon_rate_notify_cb;
+ err = clk_notifier_register(tegra->emc_clock, &tegra->rate_change_nb);
+ if (err) {
+ dev_err(&pdev->dev,
+ "Failed to register rate change notifier\n");
+ return err;
+ }
+
+ reset_control_assert(tegra->reset);
+
+ err = clk_prepare_enable(tegra->clock);
+ if (err) {
+ dev_err(&pdev->dev,
+ "Failed to prepare and enable ACTMON clock\n");
+ return err;
+ }
+
+ reset_control_deassert(tegra->reset);
+
+ tegra->max_freq = clk_round_rate(tegra->emc_clock, ULONG_MAX) / KHZ;
+ tegra->cur_freq = clk_get_rate(tegra->emc_clock) / KHZ;
+
+ actmon_writel(tegra, ACTMON_SAMPLING_PERIOD - 1,
+ ACTMON_GLB_PERIOD_CTRL);
+
+ for (i = 0; i < ARRAY_SIZE(actmon_device_configs); i++) {
+ dev = tegra->devices + i;
+ dev->config = actmon_device_configs + i;
+ dev->regs = tegra->regs + dev->config->offset;
+ spin_lock_init(&dev->lock);
+
+ tegra_actmon_configure_device(tegra, dev);
+ }
+
+ for (rate = 0; rate <= tegra->max_freq * KHZ; rate++) {
+ rate = clk_round_rate(tegra->emc_clock, rate);
+ dev_pm_opp_add(&pdev->dev, rate, 0);
+ }
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq <= 0) {
+ dev_err(&pdev->dev, "Failed to get IRQ\n");
+ return -ENODEV;
+ }
+
+ platform_set_drvdata(pdev, tegra);
+
+ err = devm_request_threaded_irq(&pdev->dev, irq, actmon_isr,
+ actmon_thread_isr, IRQF_SHARED,
+ "tegra-devfreq", tegra);
+ if (err) {
+ dev_err(&pdev->dev, "Interrupt request failed\n");
+ return err;
+ }
+
+ tegra_devfreq_profile.initial_freq = clk_get_rate(tegra->emc_clock);
+ tegra->devfreq = devm_devfreq_add_device(&pdev->dev,
+ &tegra_devfreq_profile,
+ "tegra_actmon",
+ NULL);
+
+ return 0;
+}
+
+static int tegra_devfreq_remove(struct platform_device *pdev)
+{
+ struct tegra_devfreq *tegra = platform_get_drvdata(pdev);
+ int irq = platform_get_irq(pdev, 0);
+ u32 val;
+ unsigned int i;
+
+ for (i = 0; i < ARRAY_SIZE(actmon_device_configs); i++) {
+ val = device_readl(&tegra->devices[i], ACTMON_DEV_CTRL);
+ val &= ~ACTMON_DEV_CTRL_ENB;
+ device_writel(&tegra->devices[i], val, ACTMON_DEV_CTRL);
+ }
+
+ actmon_write_barrier(tegra);
+
+ devm_free_irq(&pdev->dev, irq, tegra);
+
+ clk_notifier_unregister(tegra->emc_clock, &tegra->rate_change_nb);
+
+ clk_disable_unprepare(tegra->clock);
+
+ return 0;
+}
+
+static const struct of_device_id tegra_devfreq_of_match[] = {
+ { .compatible = "nvidia,tegra124-actmon" },
+ { },
+};
+
+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,
+ },
+};
+
+static int __init tegra_devfreq_init(void)
+{
+ int ret = 0;
+
+ ret = devfreq_add_governor(&tegra_devfreq_governor);
+ if (ret) {
+ pr_err("%s: failed to add governor: %d\n", __func__, ret);
+ return ret;
+ }
+
+ ret = platform_driver_register(&tegra_devfreq_driver);
+ if (ret)
+ devfreq_remove_governor(&tegra_devfreq_governor);
+
+ return ret;
+}
+module_init(tegra_devfreq_init)
+
+static void __exit tegra_devfreq_exit(void)
+{
+ int ret = 0;
+
+ platform_driver_unregister(&tegra_devfreq_driver);
+
+ ret = devfreq_remove_governor(&tegra_devfreq_governor);
+ if (ret)
+ pr_err("%s: failed to remove governor: %d\n", __func__, ret);
+}
+module_exit(tegra_devfreq_exit)
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Tegra devfreq driver");
+MODULE_AUTHOR("Tomeu Vizoso <tomeu.vizoso@collabora.com>");
Code Review / kvmfornfv.git / blobdiff