blob: 2d30da38c2c3e44b833a9af53dd0cfd1b770d57a [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/* Copyright 2019 Collabora ltd. */
#include <linux/clk.h>
#include <linux/devfreq.h>
#include <linux/devfreq_cooling.h>
#include <linux/nvmem-consumer.h>
#include <linux/platform_device.h>
#include <linux/pm_opp.h>
#include "panfrost_device.h"
#include "panfrost_devfreq.h"
static void panfrost_devfreq_update_utilization(struct panfrost_devfreq *pfdevfreq)
{
ktime_t now, last;
now = ktime_get();
last = pfdevfreq->time_last_update;
if (pfdevfreq->busy_count > 0)
pfdevfreq->busy_time += ktime_sub(now, last);
else
pfdevfreq->idle_time += ktime_sub(now, last);
pfdevfreq->time_last_update = now;
}
static int panfrost_devfreq_target(struct device *dev, unsigned long *freq,
u32 flags)
{
struct panfrost_device *ptdev = dev_get_drvdata(dev);
struct dev_pm_opp *opp;
int err;
opp = devfreq_recommended_opp(dev, freq, flags);
if (IS_ERR(opp))
return PTR_ERR(opp);
dev_pm_opp_put(opp);
err = dev_pm_opp_set_rate(dev, *freq);
if (!err)
ptdev->pfdevfreq.current_frequency = *freq;
return err;
}
static void panfrost_devfreq_reset(struct panfrost_devfreq *pfdevfreq)
{
pfdevfreq->busy_time = 0;
pfdevfreq->idle_time = 0;
pfdevfreq->time_last_update = ktime_get();
}
static int panfrost_devfreq_get_dev_status(struct device *dev,
struct devfreq_dev_status *status)
{
struct panfrost_device *pfdev = dev_get_drvdata(dev);
struct panfrost_devfreq *pfdevfreq = &pfdev->pfdevfreq;
unsigned long irqflags;
status->current_frequency = clk_get_rate(pfdev->clock);
spin_lock_irqsave(&pfdevfreq->lock, irqflags);
panfrost_devfreq_update_utilization(pfdevfreq);
status->total_time = ktime_to_ns(ktime_add(pfdevfreq->busy_time,
pfdevfreq->idle_time));
status->busy_time = ktime_to_ns(pfdevfreq->busy_time);
panfrost_devfreq_reset(pfdevfreq);
spin_unlock_irqrestore(&pfdevfreq->lock, irqflags);
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 struct devfreq_dev_profile panfrost_devfreq_profile = {
.timer = DEVFREQ_TIMER_DELAYED,
.polling_ms = 50, /* ~3 frames */
.target = panfrost_devfreq_target,
.get_dev_status = panfrost_devfreq_get_dev_status,
};
static int panfrost_read_speedbin(struct device *dev)
{
u32 val;
int ret;
ret = nvmem_cell_read_variable_le_u32(dev, "speed-bin", &val);
if (ret) {
/*
* -ENOENT means that this platform doesn't support speedbins
* as it didn't declare any speed-bin nvmem: in this case, we
* keep going without it; any other error means that we are
* supposed to read the bin value, but we failed doing so.
*/
if (ret != -ENOENT && ret != -EOPNOTSUPP) {
DRM_DEV_ERROR(dev, "Cannot read speed-bin (%d).", ret);
return ret;
}
return 0;
}
DRM_DEV_DEBUG(dev, "Using speed-bin = 0x%x\n", val);
return devm_pm_opp_set_supported_hw(dev, &val, 1);
}
int panfrost_devfreq_init(struct panfrost_device *pfdev)
{
int ret;
struct dev_pm_opp *opp;
unsigned long cur_freq;
struct device *dev = &pfdev->pdev->dev;
struct devfreq *devfreq;
struct thermal_cooling_device *cooling;
struct panfrost_devfreq *pfdevfreq = &pfdev->pfdevfreq;
unsigned long freq = ULONG_MAX;
if (pfdev->comp->num_supplies > 1) {
/*
* GPUs with more than 1 supply require platform-specific handling:
* continue without devfreq
*/
DRM_DEV_INFO(dev, "More than 1 supply is not supported yet\n");
return 0;
}
ret = panfrost_read_speedbin(dev);
if (ret)
return ret;
ret = devm_pm_opp_set_regulators(dev, pfdev->comp->supply_names);
if (ret) {
/* Continue if the optional regulator is missing */
if (ret != -ENODEV) {
if (ret != -EPROBE_DEFER)
DRM_DEV_ERROR(dev, "Couldn't set OPP regulators\n");
return ret;
}
}
ret = devm_pm_opp_of_add_table(dev);
if (ret) {
/* Optional, continue without devfreq */
if (ret == -ENODEV)
ret = 0;
return ret;
}
pfdevfreq->opp_of_table_added = true;
spin_lock_init(&pfdevfreq->lock);
panfrost_devfreq_reset(pfdevfreq);
cur_freq = clk_get_rate(pfdev->clock);
opp = devfreq_recommended_opp(dev, &cur_freq, 0);
if (IS_ERR(opp))
return PTR_ERR(opp);
panfrost_devfreq_profile.initial_freq = cur_freq;
/*
* We could wait until panfrost_devfreq_target() to set this value, but
* since the simple_ondemand governor works asynchronously, there's a
* chance by the time someone opens the device's fdinfo file, current
* frequency hasn't been updated yet, so let's just do an early set.
*/
pfdevfreq->current_frequency = cur_freq;
/*
* Set the recommend OPP this will enable and configure the regulator
* if any and will avoid a switch off by regulator_late_cleanup()
*/
ret = dev_pm_opp_set_opp(dev, opp);
if (ret) {
DRM_DEV_ERROR(dev, "Couldn't set recommended OPP\n");
return ret;
}
/* Find the fastest defined rate */
opp = dev_pm_opp_find_freq_floor(dev, &freq);
if (IS_ERR(opp))
return PTR_ERR(opp);
pfdevfreq->fast_rate = freq;
dev_pm_opp_put(opp);
/*
* Setup default thresholds for the simple_ondemand governor.
* The values are chosen based on experiments.
*/
pfdevfreq->gov_data.upthreshold = 45;
pfdevfreq->gov_data.downdifferential = 5;
devfreq = devm_devfreq_add_device(dev, &panfrost_devfreq_profile,
DEVFREQ_GOV_SIMPLE_ONDEMAND,
&pfdevfreq->gov_data);
if (IS_ERR(devfreq)) {
DRM_DEV_ERROR(dev, "Couldn't initialize GPU devfreq\n");
return PTR_ERR(devfreq);
}
pfdevfreq->devfreq = devfreq;
cooling = devfreq_cooling_em_register(devfreq, NULL);
if (IS_ERR(cooling))
DRM_DEV_INFO(dev, "Failed to register cooling device\n");
else
pfdevfreq->cooling = cooling;
return 0;
}
void panfrost_devfreq_fini(struct panfrost_device *pfdev)
{
struct panfrost_devfreq *pfdevfreq = &pfdev->pfdevfreq;
if (pfdevfreq->cooling) {
devfreq_cooling_unregister(pfdevfreq->cooling);
pfdevfreq->cooling = NULL;
}
}
void panfrost_devfreq_resume(struct panfrost_device *pfdev)
{
struct panfrost_devfreq *pfdevfreq = &pfdev->pfdevfreq;
if (!pfdevfreq->devfreq)
return;
panfrost_devfreq_reset(pfdevfreq);
devfreq_resume_device(pfdevfreq->devfreq);
}
void panfrost_devfreq_suspend(struct panfrost_device *pfdev)
{
struct panfrost_devfreq *pfdevfreq = &pfdev->pfdevfreq;
if (!pfdevfreq->devfreq)
return;
devfreq_suspend_device(pfdevfreq->devfreq);
}
void panfrost_devfreq_record_busy(struct panfrost_devfreq *pfdevfreq)
{
unsigned long irqflags;
if (!pfdevfreq->devfreq)
return;
spin_lock_irqsave(&pfdevfreq->lock, irqflags);
panfrost_devfreq_update_utilization(pfdevfreq);
pfdevfreq->busy_count++;
spin_unlock_irqrestore(&pfdevfreq->lock, irqflags);
}
void panfrost_devfreq_record_idle(struct panfrost_devfreq *pfdevfreq)
{
unsigned long irqflags;
if (!pfdevfreq->devfreq)
return;
spin_lock_irqsave(&pfdevfreq->lock, irqflags);
panfrost_devfreq_update_utilization(pfdevfreq);
WARN_ON(--pfdevfreq->busy_count < 0);
spin_unlock_irqrestore(&pfdevfreq->lock, irqflags);
}