blob: db798532b0b6b0bc4d20011a9ab403bb0a333176 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/* Copyright 2019 Collabora ltd. */
#include <linux/devfreq.h>
#include <linux/platform_device.h>
#include <linux/pm_opp.h>
#include <linux/clk.h>
#include <linux/regulator/consumer.h>
#include "panfrost_device.h"
#include "panfrost_devfreq.h"
#include "panfrost_features.h"
#include "panfrost_issues.h"
#include "panfrost_gpu.h"
#include "panfrost_regs.h"
static void panfrost_devfreq_update_utilization(struct panfrost_device *pfdev, int slot);
static int panfrost_devfreq_target(struct device *dev, unsigned long *freq,
u32 flags)
{
struct panfrost_device *pfdev = platform_get_drvdata(to_platform_device(dev));
struct dev_pm_opp *opp;
unsigned long old_clk_rate = pfdev->devfreq.cur_freq;
unsigned long target_volt, target_rate;
int err;
opp = devfreq_recommended_opp(dev, freq, flags);
if (IS_ERR(opp))
return PTR_ERR(opp);
target_rate = dev_pm_opp_get_freq(opp);
target_volt = dev_pm_opp_get_voltage(opp);
dev_pm_opp_put(opp);
if (old_clk_rate == target_rate)
return 0;
/*
* If frequency scaling from low to high, adjust voltage first.
* If frequency scaling from high to low, adjust frequency first.
*/
if (old_clk_rate < target_rate) {
err = regulator_set_voltage(pfdev->regulator, target_volt,
target_volt);
if (err) {
dev_err(dev, "Cannot set voltage %lu uV\n",
target_volt);
return err;
}
}
err = clk_set_rate(pfdev->clock, target_rate);
if (err) {
dev_err(dev, "Cannot set frequency %lu (%d)\n", target_rate,
err);
regulator_set_voltage(pfdev->regulator, pfdev->devfreq.cur_volt,
pfdev->devfreq.cur_volt);
return err;
}
if (old_clk_rate > target_rate) {
err = regulator_set_voltage(pfdev->regulator, target_volt,
target_volt);
if (err)
dev_err(dev, "Cannot set voltage %lu uV\n", target_volt);
}
pfdev->devfreq.cur_freq = target_rate;
pfdev->devfreq.cur_volt = target_volt;
return 0;
}
static void panfrost_devfreq_reset(struct panfrost_device *pfdev)
{
ktime_t now = ktime_get();
int i;
for (i = 0; i < NUM_JOB_SLOTS; i++) {
pfdev->devfreq.slot[i].busy_time = 0;
pfdev->devfreq.slot[i].idle_time = 0;
pfdev->devfreq.slot[i].time_last_update = now;
}
}
static int panfrost_devfreq_get_dev_status(struct device *dev,
struct devfreq_dev_status *status)
{
struct panfrost_device *pfdev = platform_get_drvdata(to_platform_device(dev));
int i;
for (i = 0; i < NUM_JOB_SLOTS; i++) {
panfrost_devfreq_update_utilization(pfdev, i);
}
status->current_frequency = clk_get_rate(pfdev->clock);
status->total_time = ktime_to_ns(ktime_add(pfdev->devfreq.slot[0].busy_time,
pfdev->devfreq.slot[0].idle_time));
status->busy_time = 0;
for (i = 0; i < NUM_JOB_SLOTS; i++) {
status->busy_time += ktime_to_ns(pfdev->devfreq.slot[i].busy_time);
}
/* We're scheduling only to one core atm, so don't divide for now */
/* status->busy_time /= NUM_JOB_SLOTS; */
panfrost_devfreq_reset(pfdev);
dev_dbg(pfdev->dev, "busy %lu total %lu %lu %% freq %lu MHz\n", status->busy_time,
status->total_time,
status->busy_time / (status->total_time / 100),
status->current_frequency / 1000 / 1000);
return 0;
}
static int panfrost_devfreq_get_cur_freq(struct device *dev, unsigned long *freq)
{
struct panfrost_device *pfdev = platform_get_drvdata(to_platform_device(dev));
*freq = pfdev->devfreq.cur_freq;
return 0;
}
static struct devfreq_dev_profile panfrost_devfreq_profile = {
.polling_ms = 50, /* ~3 frames */
.target = panfrost_devfreq_target,
.get_dev_status = panfrost_devfreq_get_dev_status,
.get_cur_freq = panfrost_devfreq_get_cur_freq,
};
int panfrost_devfreq_init(struct panfrost_device *pfdev)
{
int ret;
struct dev_pm_opp *opp;
if (!pfdev->regulator)
return 0;
ret = dev_pm_opp_of_add_table(&pfdev->pdev->dev);
if (ret == -ENODEV) /* Optional, continue without devfreq */
return 0;
else if (ret)
return ret;
panfrost_devfreq_reset(pfdev);
pfdev->devfreq.cur_freq = clk_get_rate(pfdev->clock);
opp = devfreq_recommended_opp(&pfdev->pdev->dev, &pfdev->devfreq.cur_freq, 0);
if (IS_ERR(opp))
return PTR_ERR(opp);
panfrost_devfreq_profile.initial_freq = pfdev->devfreq.cur_freq;
dev_pm_opp_put(opp);
pfdev->devfreq.devfreq = devm_devfreq_add_device(&pfdev->pdev->dev,
&panfrost_devfreq_profile, "simple_ondemand", NULL);
if (IS_ERR(pfdev->devfreq.devfreq)) {
DRM_DEV_ERROR(&pfdev->pdev->dev, "Couldn't initialize GPU devfreq\n");
ret = PTR_ERR(pfdev->devfreq.devfreq);
pfdev->devfreq.devfreq = NULL;
return ret;
}
return 0;
}
void panfrost_devfreq_resume(struct panfrost_device *pfdev)
{
int i;
if (!pfdev->devfreq.devfreq)
return;
panfrost_devfreq_reset(pfdev);
for (i = 0; i < NUM_JOB_SLOTS; i++)
pfdev->devfreq.slot[i].busy = false;
devfreq_resume_device(pfdev->devfreq.devfreq);
}
void panfrost_devfreq_suspend(struct panfrost_device *pfdev)
{
if (!pfdev->devfreq.devfreq)
return;
devfreq_suspend_device(pfdev->devfreq.devfreq);
}
static void panfrost_devfreq_update_utilization(struct panfrost_device *pfdev, int slot)
{
struct panfrost_devfreq_slot *devfreq_slot = &pfdev->devfreq.slot[slot];
ktime_t now;
ktime_t last;
if (!pfdev->devfreq.devfreq)
return;
now = ktime_get();
last = pfdev->devfreq.slot[slot].time_last_update;
/* If we last recorded a transition to busy, we have been idle since */
if (devfreq_slot->busy)
pfdev->devfreq.slot[slot].busy_time += ktime_sub(now, last);
else
pfdev->devfreq.slot[slot].idle_time += ktime_sub(now, last);
pfdev->devfreq.slot[slot].time_last_update = now;
}
/* The job scheduler is expected to call this at every transition busy <-> idle */
void panfrost_devfreq_record_transition(struct panfrost_device *pfdev, int slot)
{
struct panfrost_devfreq_slot *devfreq_slot = &pfdev->devfreq.slot[slot];
panfrost_devfreq_update_utilization(pfdev, slot);
devfreq_slot->busy = !devfreq_slot->busy;
}