363 lines
9.0 KiB
C

/*
* gk20a clock scaling profile
*
* Copyright (c) 2013, 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.
*
* 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/devfreq.h>
#include <linux/debugfs.h>
#include <linux/types.h>
#include <linux/clk.h>
#include <linux/export.h>
#include <linux/slab.h>
#include <linux/clk/tegra.h>
#include <linux/tegra-soc.h>
#include <governor.h>
#include "dev.h"
#include "chip_support.h"
#include "nvhost_acm.h"
#include "gk20a.h"
#include "pmu_gk20a.h"
#include "clk_gk20a.h"
#include "nvhost_scale.h"
#include "gk20a_scale.h"
#include "gk20a_dvfs.h"
#include "gr3d/scale3d.h"
static ssize_t nvhost_gk20a_scale_load_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct platform_device *pdev = to_platform_device(dev);
struct gk20a *g = get_gk20a(pdev);
u32 busy_time;
ssize_t res;
if (!g->power_on) {
busy_time = 0;
} else {
gk20a_busy(g->dev);
gk20a_pmu_load_norm(g, &busy_time);
gk20a_idle(g->dev);
}
res = snprintf(buf, PAGE_SIZE, "%u\n", busy_time);
return res;
}
static DEVICE_ATTR(load, S_IRUGO, nvhost_gk20a_scale_load_show, NULL);
/*
* nvhost_gk20a_scale_callback(profile, freq)
*
* This function sets emc frequency based on current gpu frequency
*/
void nvhost_gk20a_scale_callback(struct nvhost_device_profile *profile,
unsigned long freq)
{
struct gk20a *g = get_gk20a(profile->pdev);
struct nvhost_emc_params *emc_params = profile->private_data;
long after = gk20a_clk_get_rate(g);
long emc_target = nvhost_scale3d_get_emc_rate(emc_params, after);
nvhost_module_set_devfreq_rate(profile->pdev, 2, emc_target);
}
/*
* nvhost_scale_make_freq_table(profile)
*
* This function initialises the frequency table for the given device profile
*/
static int nvhost_scale_make_freq_table(struct nvhost_device_profile *profile)
{
struct gk20a *g = get_gk20a(profile->pdev);
unsigned long *freqs;
int num_freqs, err;
/* make sure the clock is available */
if (!gk20a_clk_get(g))
return -ENOSYS;
/* get gpu dvfs table */
err = gk20a_dvfs_get_freqs(g, &freqs, &num_freqs);
if (err)
return -ENOSYS;
profile->devfreq_profile.freq_table = (unsigned int *)freqs;
profile->devfreq_profile.max_state = num_freqs;
return 0;
}
/*
* gk20a_scale_target(dev, *freq, flags)
*
* This function scales the clock
*/
static int gk20a_scale_target(struct device *dev, unsigned long *freq,
u32 flags)
{
struct gk20a *g = get_gk20a(to_platform_device(dev));
struct nvhost_device_data *pdata = dev_get_drvdata(dev);
struct nvhost_device_profile *profile = pdata->power_profile;
unsigned long rounded_rate = gk20a_clk_round_rate(g, *freq);
unsigned long old_rate = gk20a_clk_get_rate(g);
if (rounded_rate == old_rate) {
*freq = rounded_rate;
return 0;
}
if (rounded_rate > old_rate)
gk20a_dvfs_adjust_voltage(g, rounded_rate);
gk20a_clk_set_rate(g, rounded_rate);
if (pdata->scaling_post_cb)
pdata->scaling_post_cb(profile, rounded_rate);
if (rounded_rate < old_rate)
gk20a_dvfs_adjust_voltage(g, rounded_rate);
*freq = gk20a_clk_get_rate(g);
return 0;
}
/*
* update_load_estimate_gpmu(profile)
*
* Update load estimate using gpmu. The gpmu value is normalised
* based on the time it was asked last time.
*/
static void update_load_estimate_gpmu(struct platform_device *pdev)
{
struct nvhost_device_data *pdata = platform_get_drvdata(pdev);
struct nvhost_device_profile *profile = pdata->power_profile;
struct gk20a *g = get_gk20a(pdev);
unsigned long dt;
u32 busy_time;
ktime_t t;
t = ktime_get();
dt = ktime_us_delta(t, profile->last_event_time);
profile->dev_stat.total_time = dt;
profile->last_event_time = t;
gk20a_pmu_load_norm(g, &busy_time);
profile->dev_stat.busy_time = (busy_time * dt) / 1000;
}
/*
* gk20a_scale_notify(pdev, busy)
*
* Calling this function informs that the device is idling (..or busy). This
* data is used to estimate the current load
*/
static void gk20a_scale_notify(struct platform_device *pdev, bool busy)
{
struct nvhost_device_data *pdata = platform_get_drvdata(pdev);
struct nvhost_device_profile *profile = pdata->power_profile;
struct devfreq *devfreq = pdata->power_manager;
/* Is the device profile initialised? */
if (!(profile && devfreq))
return;
mutex_lock(&devfreq->lock);
profile->last_event_type = busy ? DEVICE_BUSY : DEVICE_IDLE;
update_devfreq(devfreq);
mutex_unlock(&devfreq->lock);
}
void nvhost_gk20a_scale_notify_idle(struct platform_device *pdev)
{
gk20a_scale_notify(pdev, false);
}
void nvhost_gk20a_scale_notify_busy(struct platform_device *pdev)
{
gk20a_scale_notify(pdev, true);
}
/*
* gk20a_scale_get_dev_status(dev, *stat)
*
* This function queries the current device status.
*/
static int gk20a_scale_get_dev_status(struct device *dev,
struct devfreq_dev_status *stat)
{
struct nvhost_device_data *pdata = dev_get_drvdata(dev);
struct nvhost_device_profile *profile = pdata->power_profile;
struct gk20a *g = get_gk20a(to_platform_device(dev));
/* Make sure there are correct values for the current frequency */
profile->dev_stat.current_frequency = gk20a_clk_get_rate(g);
/* Update load estimate */
update_load_estimate_gpmu(to_platform_device(dev));
/* Copy the contents of the current device status */
profile->ext_stat.busy = profile->last_event_type;
*stat = profile->dev_stat;
/* Finally, clear out the local values */
profile->dev_stat.total_time = 0;
profile->dev_stat.busy_time = 0;
return 0;
}
/*
* gk20a_scale_init(pdev)
*/
void nvhost_gk20a_scale_init(struct platform_device *pdev)
{
struct gk20a *g = get_gk20a(pdev);
struct nvhost_device_data *pdata = platform_get_drvdata(pdev);
struct nvhost_device_profile *profile;
struct nvhost_emc_params *emc_params;
if (pdata->power_profile)
return;
profile = kzalloc(sizeof(struct nvhost_device_profile), GFP_KERNEL);
emc_params = kzalloc(sizeof(*emc_params), GFP_KERNEL);
if (!(profile && emc_params)) {
kfree(profile);
kfree(emc_params);
return;
}
profile->pdev = pdev;
profile->last_event_type = DEVICE_IDLE;
profile->private_data = emc_params;
if (gk20a_dvfs_init(pdev, g)) {
dev_warn(&pdev->dev, "failed to initialize gk20a dvfs\n");
goto err_init_dvfs;
}
/* Initialize devfreq related structures */
profile->dev_stat.private_data = &profile->ext_stat;
profile->ext_stat.min_freq = gk20a_dvfs_get_min_freq(g);
profile->ext_stat.max_freq = gk20a_dvfs_get_max_freq(g);
profile->ext_stat.busy = DEVICE_IDLE;
if (profile->ext_stat.min_freq == profile->ext_stat.max_freq) {
dev_warn(&pdev->dev, "max rate = min rate (%lu), disabling scaling\n",
profile->ext_stat.min_freq);
goto err_fetch_clocks;
}
nvhost_scale3d_calibrate_emc(emc_params,
gk20a_clk_get(g), pdata->clk[2],
pdata->linear_emc);
if (device_create_file(&pdev->dev, &dev_attr_load))
goto err_create_sysfs_entry;
/* Store device profile so we can access it if devfreq governor
* init needs that */
pdata->power_profile = profile;
if (pdata->devfreq_governor) {
struct devfreq *devfreq;
int err;
profile->devfreq_profile.initial_freq =
profile->ext_stat.min_freq;
profile->devfreq_profile.target = gk20a_scale_target;
profile->devfreq_profile.get_dev_status =
gk20a_scale_get_dev_status;
err = nvhost_scale_make_freq_table(profile);
if (err)
goto err_get_freqs;
devfreq = devfreq_add_device(&pdev->dev,
&profile->devfreq_profile,
pdata->devfreq_governor, NULL);
if (IS_ERR(devfreq))
devfreq = NULL;
pdata->power_manager = devfreq;
}
return;
err_init_dvfs:
err_get_freqs:
device_remove_file(&pdev->dev, &dev_attr_load);
err_create_sysfs_entry:
err_fetch_clocks:
kfree(pdata->power_profile);
pdata->power_profile = NULL;
}
/*
* gk20a_scale_deinit(dev)
*
* Stop scaling for the given device.
*/
void nvhost_gk20a_scale_deinit(struct platform_device *pdev)
{
struct nvhost_device_data *pdata = platform_get_drvdata(pdev);
struct nvhost_device_profile *profile = pdata->power_profile;
if (!profile)
return;
if (pdata->power_manager)
devfreq_remove_device(pdata->power_manager);
device_remove_file(&pdev->dev, &dev_attr_load);
kfree(profile);
pdata->power_profile = NULL;
}
/*
* gk20a_scale_hw_init(dev)
*
* Initialize hardware portion of the device
*/
void nvhost_gk20a_scale_hw_init(struct platform_device *pdev)
{
struct nvhost_device_data *pdata = platform_get_drvdata(pdev);
struct nvhost_device_profile *profile = pdata->power_profile;
/* make sure that scaling has bee initialised */
if (!profile)
return;
profile->dev_stat.total_time = 0;
profile->last_event_time = ktime_get();
}