/*
* drivers/video/tegra/host/gr3d/pod_scaling.c
*
* Tegra Graphics Host 3D clock scaling
*
* Copyright (c) 2012-2013, 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 .
*/
/*
* Power-on-demand clock scaling for nvhost devices
*
* devfreq calls nvhost_pod_estimate_freq() for estimating the new
* frequency for the device. The clocking is done using two properties:
*
* (1) Usually the governor receives actively throughput hints that indicate
* whether scaling up or down is required.
* (2) The load of the device is estimated using the busy times from the
* device profile. This information indicates if the device frequency
* should be altered.
*
*/
#include
#include
#include
#include
#include
#include
#include
#include
#include
#ifdef CONFIG_TEGRA_THROUGHPUT
#include
#endif
#define CREATE_TRACE_POINTS
#include
#include
#include "nvhost_acm.h"
#include "scale3d.h"
#include "pod_scaling.h"
#include "dev.h"
/* time frame for load and hint tracking - when events come in at a larger
* interval, this probably indicates the current estimates are stale
*/
#define GR3D_TIMEFRAME 1000000 /* 1 sec */
/* the number of frames to use in the running average of load estimates and
* throughput hints. Choosing 6 frames targets a window of about 100 msec.
* Large flucutuations in frame times require a window that's large enough to
* prevent spiky scaling behavior, which in turn exacerbates frame rate
* instability.
*/
static int podgov_is_enabled(struct device *dev);
static void podgov_enable(struct device *dev, int enable);
static int podgov_user_ctl(struct device *dev);
static void podgov_set_user_ctl(struct device *dev, int enable);
static struct devfreq_governor nvhost_podgov;
/*******************************************************************************
* podgov_info_rec - gr3d scaling governor specific parameters
******************************************************************************/
struct podgov_info_rec {
int enable;
int init;
ktime_t last_throughput_hint;
ktime_t last_scale;
ktime_t last_freq_estimate;
struct delayed_work idle_timer;
unsigned int p_slowdown_delay;
unsigned int p_block_window;
unsigned int p_use_throughput_hint;
unsigned int p_hint_lo_limit;
unsigned int p_hint_hi_limit;
unsigned int p_scaleup_limit;
unsigned int p_scaledown_limit;
unsigned int p_smooth;
unsigned int p_smooth_long;
int p_damp;
int p_load_max;
int p_load_target;
int p_bias;
unsigned int p_user;
unsigned int p_freq_request;
long idle;
int adjustment_type;
unsigned long adjustment_frequency;
int last_event_type;
struct devfreq *power_manager;
struct dentry *debugdir;
int *freqlist;
int freq_count;
unsigned int idle_avg_short;
unsigned int idle_avg_long;
int freq_avg;
unsigned int hint_avg;
int block;
struct notifier_block throughput_hint_notifier;
};
/*******************************************************************************
* Adjustment type is used to tell the source that requested frequency re-
* estimation. Type ADJUSTMENT_LOCAL indicates that the re-estimation was
* initiated by the governor itself. This happens when one of the worker
* threads want to adjust the frequency.
*
* ADJUSTMENT_DEVICE_REQ (default value) indicates that the adjustment was
* initiated by a device event.
******************************************************************************/
enum podgov_adjustment_type {
ADJUSTMENT_LOCAL = 0,
ADJUSTMENT_DEVICE_REQ = 1
};
static void stop_podgov_workers(struct podgov_info_rec *podgov)
{
/* idle_timer can rearm itself */
do {
cancel_delayed_work_sync(&podgov->idle_timer);
} while (delayed_work_pending(&podgov->idle_timer));
}
/*******************************************************************************
* scaling_limit(df, freq)
*
* Limit the given frequency
******************************************************************************/
static void scaling_limit(struct devfreq *df, unsigned long *freq)
{
if (*freq < df->min_freq)
*freq = df->min_freq;
else if (*freq > df->max_freq)
*freq = df->max_freq;
}
/*******************************************************************************
* nvhost_scale3d_suspend(dev)
*
* Prepare the device for suspend
******************************************************************************/
void nvhost_scale3d_suspend(struct device *dev)
{
struct nvhost_device_data *pdata = dev_get_drvdata(dev);
struct devfreq *df = pdata->power_manager;
struct podgov_info_rec *podgov;
if (!df)
return;
mutex_lock(&df->lock);
podgov = df->data;
if (!(df->governor == &nvhost_podgov &&
podgov && podgov->enable)) {
mutex_unlock(&df->lock);
return;
}
mutex_unlock(&df->lock);
stop_podgov_workers(podgov);
}
/*******************************************************************************
* podgov_is_enabled(dev)
*
* Check whether the device is enabled or not.
******************************************************************************/
static int podgov_is_enabled(struct device *dev)
{
struct platform_device *d = to_platform_device(dev);
struct nvhost_device_data *pdata = platform_get_drvdata(d);
struct devfreq *df = pdata->power_manager;
struct podgov_info_rec *podgov;
int enable;
if (!df)
return 0;
mutex_lock(&df->lock);
podgov = df->data;
enable = podgov->enable;
mutex_unlock(&df->lock);
return enable;
}
/*******************************************************************************
* podgov_enable(dev, enable)
*
* This function enables (enable=1) or disables (enable=0) the automatic scaling
* of the device. If the device is disabled, the device's clock is set to its
* maximum.
******************************************************************************/
static void podgov_enable(struct device *dev, int enable)
{
struct platform_device *d = to_platform_device(dev);
struct nvhost_device_data *pdata = platform_get_drvdata(d);
struct devfreq *df = pdata->power_manager;
struct podgov_info_rec *podgov;
if (!df)
return;
/* make sure the device is alive before doing any scaling */
nvhost_module_busy_noresume(d);
mutex_lock(&df->lock);
podgov = df->data;
trace_podgov_enabled(enable);
/* bad configuration. quit. */
if (df->min_freq == df->max_freq)
goto exit_unlock;
/* store the enable information */
podgov->enable = enable;
/* skip local adjustment if we are enabling or the device is
* suspended */
if (enable || !pm_runtime_active(&d->dev))
goto exit_unlock;
/* full speed */
podgov->adjustment_frequency = df->max_freq;
podgov->adjustment_type = ADJUSTMENT_LOCAL;
update_devfreq(df);
mutex_unlock(&df->lock);
nvhost_module_idle(d);
stop_podgov_workers(podgov);
return;
exit_unlock:
mutex_unlock(&df->lock);
nvhost_module_idle(d);
}
/*******************************************************************************
* podgov_user_ctl(dev)
*
* Check whether the gpu scaling is set to user space control.
******************************************************************************/
static int podgov_user_ctl(struct device *dev)
{
struct platform_device *d = to_platform_device(dev);
struct nvhost_device_data *pdata = platform_get_drvdata(d);
struct devfreq *df = pdata->power_manager;
struct podgov_info_rec *podgov;
int user;
if (!df)
return 0;
mutex_lock(&df->lock);
podgov = df->data;
user = podgov->p_user;
mutex_unlock(&df->lock);
return user;
}
/*****************************************************************************
* podgov_set_user_ctl(dev, user)
*
* This function enables or disables user control of the gpu. If user control
* is enabled, setting the freq_request controls the gpu frequency, and other
* gpu scaling mechanisms are disabled.
******************************************************************************/
static void podgov_set_user_ctl(struct device *dev, int user)
{
struct platform_device *d = to_platform_device(dev);
struct nvhost_device_data *pdata = platform_get_drvdata(d);
struct devfreq *df = pdata->power_manager;
struct podgov_info_rec *podgov;
int old_user;
if (!df)
return;
/* make sure the device is alive before doing any scaling */
nvhost_module_busy_noresume(d);
mutex_lock(&df->lock);
podgov = df->data;
trace_podgov_set_user_ctl(user);
/* store the new user value */
old_user = podgov->p_user;
podgov->p_user = user;
/* skip scaling, if scaling (or the whole device) is turned off
* - or the scaling already was in user mode */
if (!pm_runtime_active(&d->dev) || !podgov->enable ||
!(user && !old_user))
goto exit_unlock;
/* write request */
podgov->adjustment_frequency = podgov->p_freq_request;
podgov->adjustment_type = ADJUSTMENT_LOCAL;
update_devfreq(df);
mutex_unlock(&df->lock);
nvhost_module_idle(d);
stop_podgov_workers(podgov);
return;
exit_unlock:
mutex_unlock(&df->lock);
nvhost_module_idle(d);
}
/*******************************************************************************
* podgov_get_freq_request(dev)
*
* return the latest freq request if anybody asks
******************************************************************************/
static int podgov_get_freq_request(struct device *dev)
{
struct platform_device *d = to_platform_device(dev);
struct nvhost_device_data *pdata = platform_get_drvdata(d);
struct devfreq *df = pdata->power_manager;
struct podgov_info_rec *podgov;
int freq_request;
if (!df)
return 0;
mutex_lock(&df->lock);
podgov = df->data;
freq_request = podgov->p_freq_request;
mutex_unlock(&df->lock);
return freq_request;
}
/*****************************************************************************
* podgov_set_freq_request(dev, user)
*
* Set the current freq request. If scaling is enabled, and podgov user space
* control is enabled, this will set the gpu frequency.
******************************************************************************/
static void podgov_set_freq_request(struct device *dev, int freq_request)
{
struct platform_device *d = to_platform_device(dev);
struct nvhost_device_data *pdata = platform_get_drvdata(d);
struct devfreq *df = pdata->power_manager;
struct podgov_info_rec *podgov;
if (!df)
return;
/* make sure the device is alive before doing any scaling */
nvhost_module_busy_noresume(d);
mutex_lock(&df->lock);
podgov = df->data;
trace_podgov_set_freq_request(freq_request);
podgov->p_freq_request = freq_request;
/* update the request only if podgov is enabled, device is turned on
* and the scaling is in user mode */
if (podgov->enable && podgov->p_user &&
pm_runtime_active(&d->dev)) {
podgov->adjustment_frequency = freq_request;
podgov->adjustment_type = ADJUSTMENT_LOCAL;
update_devfreq(df);
}
mutex_unlock(&df->lock);
nvhost_module_idle(d);
}
/*******************************************************************************
* freq = scaling_state_check(df, time)
*
* This handler is called to adjust the frequency of the device. The function
* returns the desired frequency for the clock. If there is no need to tune the
* clock immediately, 0 is returned.
******************************************************************************/
static unsigned long scaling_state_check(struct devfreq *df, ktime_t time)
{
struct podgov_info_rec *podgov = df->data;
unsigned long dt;
long max_boost, load, damp, freq, boost, res;
dt = (unsigned long) ktime_us_delta(time, podgov->last_scale);
if (dt < podgov->p_block_window || df->previous_freq == 0)
return 0;
freq = df->previous_freq;
max_boost = df->max_freq / 3;
/* calculate and trace load */
load = 1000 - podgov->idle_avg_long;
trace_podgov_busy(load);
damp = podgov->p_damp;
if ((1000 - podgov->idle_avg_short) > podgov->p_load_max) {
/* if too busy, scale up max/3, do not damp */
boost = max_boost;
damp = 10;
} else {
/* boost = bias * freq * (load - target)/target */
boost = (load - podgov->p_load_target);
boost *= (podgov->p_bias * freq);
boost /= (100 * podgov->p_load_target);
/* clamp to max boost */
boost = (boost < max_boost) ? boost : max_boost;
}
/* calculate new request */
res = freq + boost;
/* Maintain average request */
podgov->freq_avg = (podgov->freq_avg * podgov->p_smooth) + res;
podgov->freq_avg /= (podgov->p_smooth+1);
/* Applying damping to frequencies */
res = ((damp * res) + ((10 - damp)*podgov->freq_avg)) / 10;
/* Check limit, and apply */
scaling_limit(df, &res);
trace_podgov_scaling_state_check(df->previous_freq, res);
return res;
}
/*******************************************************************************
* freqlist_up(podgov, target, steps)
*
* This function determines the frequency that is "steps" frequency steps
* higher compared to the target frequency.
******************************************************************************/
int freqlist_up(struct podgov_info_rec *podgov, long target, int steps)
{
int i, pos;
for (i = 0; i < podgov->freq_count; i++)
if (podgov->freqlist[i] >= target)
break;
pos = min(podgov->freq_count - 1, i + steps);
return podgov->freqlist[pos];
}
/*******************************************************************************
* freqlist_down(podgov, target, steps)
*
* This function determines the frequency that is "steps" frequency steps
* lower compared to the target frequency.
******************************************************************************/
int freqlist_down(struct podgov_info_rec *podgov, long target, int steps)
{
int i, pos;
for (i = podgov->freq_count - 1; i >= 0; i--)
if (podgov->freqlist[i] <= target)
break;
pos = max(0, i - steps);
return podgov->freqlist[pos];
}
/*******************************************************************************
* podgov_idle_handler(work)
*
* This handler is called after the device has been idle long enough. This
* handler forms a (positive) feedback loop by notifying idle to the device.
******************************************************************************/
static void podgov_idle_handler(struct work_struct *work)
{
struct delayed_work *idle_timer =
container_of(work, struct delayed_work, work);
struct podgov_info_rec *podgov =
container_of(idle_timer, struct podgov_info_rec, idle_timer);
struct devfreq *df = podgov->power_manager;
/* Retrieve device driver ops and the device struct */
struct device *d = df->dev.parent;
struct platform_device *dev = to_platform_device(d);
struct nvhost_device_data *pdata = platform_get_drvdata(dev);
int notify_idle = 0;
mutex_lock(&df->lock);
if (!podgov->enable) {
mutex_unlock(&df->lock);
return;
}
if (podgov->last_event_type == DEVICE_IDLE &&
df->previous_freq > df->min_freq &&
podgov->p_user == false)
notify_idle = 1;
mutex_unlock(&df->lock);
if (pdata->idle && notify_idle)
pdata->idle(dev);
}
/*******************************************************************************
* nvhost_scale3d_set_throughput_hint(hint)
*
* This function can be used to request scaling up or down based on the
* required throughput
******************************************************************************/
#ifdef CONFIG_TEGRA_THROUGHPUT
static int nvhost_scale3d_set_throughput_hint(struct notifier_block *nb,
unsigned long action, void *data)
{
struct podgov_info_rec *podgov =
container_of(nb, struct podgov_info_rec,
throughput_hint_notifier);
struct devfreq *df;
struct platform_device *pdev;
int hint = tegra_throughput_get_hint();
long idle;
long curr, target;
int avg_idle, avg_hint, scale_score;
unsigned int smooth;
if (!podgov)
return NOTIFY_DONE;
df = podgov->power_manager;
if (!df)
return NOTIFY_DONE;
pdev = to_platform_device(df->dev.parent);
/* make sure the device is alive before doing any scaling */
nvhost_module_busy_noresume(pdev);
if (!pm_runtime_active(&pdev->dev)) {
nvhost_module_idle(pdev);
return 0;
}
mutex_lock(&podgov->power_manager->lock);
podgov->block--;
if (!podgov->enable ||
!podgov->p_use_throughput_hint ||
podgov->block > 0)
goto exit_unlock;
trace_podgov_hint(podgov->idle, hint);
podgov->last_throughput_hint = ktime_get();
curr = podgov->power_manager->previous_freq;
idle = podgov->idle;
avg_idle = podgov->idle_avg_short;
smooth = podgov->p_smooth;
/* compute averages usings exponential-moving-average */
avg_hint = ((smooth*podgov->hint_avg + hint)/(smooth+1));
podgov->hint_avg = avg_hint;
/* set the target using avg_hint and avg_idle */
target = curr;
if (avg_hint < podgov->p_hint_lo_limit) {
target = freqlist_up(podgov, curr, 1);
} else {
scale_score = avg_idle + avg_hint;
if (scale_score > podgov->p_scaledown_limit)
target = freqlist_down(podgov, curr, 1);
else if (scale_score < podgov->p_scaleup_limit
&& hint < podgov->p_hint_hi_limit)
target = freqlist_up(podgov, curr, 1);
}
/* clamp and apply target */
scaling_limit(df, &target);
if (target != curr) {
podgov->block = podgov->p_smooth;
trace_podgov_do_scale(df->previous_freq, target);
podgov->adjustment_frequency = target;
podgov->adjustment_type = ADJUSTMENT_LOCAL;
update_devfreq(df);
}
trace_podgov_print_target(idle, avg_idle, curr, target, hint,
avg_hint);
exit_unlock:
mutex_unlock(&podgov->power_manager->lock);
nvhost_module_idle(pdev);
return NOTIFY_OK;
}
#endif
/*******************************************************************************
* debugfs interface for controlling 3d clock scaling on the fly
******************************************************************************/
#ifdef CONFIG_DEBUG_FS
static void nvhost_scale3d_debug_init(struct devfreq *df)
{
struct podgov_info_rec *podgov = df->data;
struct platform_device *dev = to_platform_device(df->dev.parent);
struct nvhost_device_data *pdata = platform_get_drvdata(dev);
struct dentry *f;
if (!podgov)
return;
podgov->debugdir = debugfs_create_dir("scaling", pdata->debugfs);
if (!podgov->debugdir) {
pr_err("podgov: can\'t create debugfs directory\n");
return;
}
#define CREATE_PODGOV_FILE(fname) \
do {\
f = debugfs_create_u32(#fname, S_IRUGO | S_IWUSR, \
podgov->debugdir, &podgov->p_##fname); \
if (NULL == f) { \
pr_err("podgov: can\'t create file " #fname "\n"); \
return; \
} \
} while (0)
CREATE_PODGOV_FILE(block_window);
CREATE_PODGOV_FILE(load_max);
CREATE_PODGOV_FILE(load_target);
CREATE_PODGOV_FILE(bias);
CREATE_PODGOV_FILE(damp);
CREATE_PODGOV_FILE(use_throughput_hint);
CREATE_PODGOV_FILE(hint_hi_limit);
CREATE_PODGOV_FILE(hint_lo_limit);
CREATE_PODGOV_FILE(scaleup_limit);
CREATE_PODGOV_FILE(scaledown_limit);
CREATE_PODGOV_FILE(smooth);
CREATE_PODGOV_FILE(smooth_long);
CREATE_PODGOV_FILE(slowdown_delay);
#undef CREATE_PODGOV_FILE
}
static void nvhost_scale3d_debug_deinit(struct devfreq *df)
{
struct podgov_info_rec *podgov = df->data;
debugfs_remove_recursive(podgov->debugdir);
}
#else
static void nvhost_scale3d_debug_init(struct devfreq *df)
{
(void)df;
}
static void nvhost_scale3d_debug_deinit(struct devfreq *df)
{
(void)df;
}
#endif
/*******************************************************************************
* sysfs interface for enabling/disabling 3d scaling
******************************************************************************/
static ssize_t enable_3d_scaling_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
ssize_t res;
res = snprintf(buf, PAGE_SIZE, "%d\n", podgov_is_enabled(dev));
return res;
}
static ssize_t enable_3d_scaling_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
unsigned long val = 0;
if (kstrtoul(buf, 10, &val) < 0)
return -EINVAL;
podgov_enable(dev, val);
return count;
}
static DEVICE_ATTR(enable_3d_scaling, S_IRUGO | S_IWUSR,
enable_3d_scaling_show, enable_3d_scaling_store);
/*******************************************************************************
* sysfs interface for user space control
* user = [0,1] disables / enabled user space control
* freq_request is the sysfs node user space writes frequency requests to
******************************************************************************/
static ssize_t user_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
ssize_t res;
res = snprintf(buf, PAGE_SIZE, "%d\n", podgov_user_ctl(dev));
return res;
}
static ssize_t user_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
unsigned long val = 0;
if (kstrtoul(buf, 10, &val) < 0)
return -EINVAL;
podgov_set_user_ctl(dev, val);
return count;
}
static DEVICE_ATTR(user, S_IRUGO | S_IWUSR,
user_show, user_store);
static ssize_t freq_request_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
ssize_t res;
res = snprintf(buf, PAGE_SIZE, "%d\n", podgov_get_freq_request(dev));
return res;
}
static ssize_t freq_request_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
unsigned long val = 0;
if (kstrtoul(buf, 10, &val) < 0)
return -EINVAL;
podgov_set_freq_request(dev, val);
return count;
}
static DEVICE_ATTR(freq_request, S_IRUGO | S_IWUSR,
freq_request_show, freq_request_store);
/*******************************************************************************
* nvhost_pod_estimate_freq(df, freq)
*
* This function is called for re-estimating the frequency. The function is
* called in three conditions:
*
* (1) Internal request to change the frequency. In this case a new clock
* target is immediately set for the device.
* (2) Call from the client (something has happened and re-estimation
* is required).
* (3) Some other reason (i.e. periodic call)
*
******************************************************************************/
static int nvhost_pod_estimate_freq(struct devfreq *df,
unsigned long *freq)
{
struct podgov_info_rec *podgov = df->data;
struct devfreq_dev_status dev_stat;
struct nvhost_devfreq_ext_stat *ext_stat;
int current_event;
int stat;
ktime_t now;
unsigned long time_diff;
unsigned int avg_window;
stat = df->profile->get_dev_status(df->dev.parent, &dev_stat);
if (stat < 0)
return stat;
/* Ensure maximal clock when scaling is disabled */
if (!podgov->enable) {
*freq = df->max_freq;
return 0;
}
if (podgov->p_user) {
*freq = podgov->p_freq_request;
return 0;
}
current_event = DEVICE_IDLE;
stat = 0;
now = ktime_get();
/* calculate the time slice since we were last run */
time_diff = (unsigned long) ktime_us_delta(now,
podgov->last_freq_estimate) + 1;
podgov->last_freq_estimate = now;
/* Local adjustments (i.e. requests from kernel threads) are
* handled here */
if (podgov->adjustment_type == ADJUSTMENT_LOCAL) {
podgov->adjustment_type = ADJUSTMENT_DEVICE_REQ;
/* Do not do unnecessary scaling */
scaling_limit(df, &podgov->adjustment_frequency);
/* Round the frequency and check if we're already there */
if (freqlist_up(podgov, podgov->adjustment_frequency, 0) ==
dev_stat.current_frequency)
return GET_TARGET_FREQ_DONTSCALE;
trace_podgov_estimate_freq(df->previous_freq,
podgov->adjustment_frequency);
*freq = podgov->adjustment_frequency;
return 0;
}
/* Retrieve extended data */
ext_stat = dev_stat.private_data;
if (!ext_stat)
return -EINVAL;
current_event = ext_stat->busy;
*freq = dev_stat.current_frequency;
df->min_freq = ext_stat->min_freq;
df->max_freq = ext_stat->max_freq;
/* Sustain local variables */
podgov->last_event_type = current_event;
podgov->idle = 1000 * (dev_stat.total_time - dev_stat.busy_time);
podgov->idle = podgov->idle / dev_stat.total_time;
/* avg_window changes based on how long this sample was compared
* to how long we want to smooth over. If the time diff is high
* enough then avg_window will go to 0, which will cause the calculated
* average to be the current idle value. This is desired behavior,
* because if a long time interval has passed the previous averaging
* data is no longer valid. */
avg_window = podgov->p_smooth * 1000 / time_diff;
podgov->idle_avg_short = (avg_window * podgov->idle_avg_short) +
podgov->idle;
podgov->idle_avg_short = podgov->idle_avg_short / (avg_window + 1);
avg_window = podgov->p_smooth_long * 1000 / time_diff;
podgov->idle_avg_long = (avg_window * podgov->idle_avg_long) +
podgov->idle;
podgov->idle_avg_long = podgov->idle_avg_long / (avg_window + 1);
/* if throughput hint enabled, and last hint is recent enough, return */
if (podgov->p_use_throughput_hint &&
ktime_us_delta(now, podgov->last_throughput_hint) < 1000000)
return GET_TARGET_FREQ_DONTSCALE;
switch (current_event) {
case DEVICE_IDLE:
/* Launch a work to slowdown the gpu */
*freq = scaling_state_check(df, now);
schedule_delayed_work(&podgov->idle_timer,
msecs_to_jiffies(podgov->p_slowdown_delay));
break;
case DEVICE_BUSY:
cancel_delayed_work(&podgov->idle_timer);
*freq = scaling_state_check(df, now);
break;
}
if (!(*freq) ||
(freqlist_up(podgov, *freq, 0) == dev_stat.current_frequency))
return GET_TARGET_FREQ_DONTSCALE;
podgov->last_scale = now;
trace_podgov_estimate_freq(df->previous_freq, *freq);
return 0;
}
/*******************************************************************************
* nvhost_pod_init(struct devfreq *df)
*
* Governor initialisation.
******************************************************************************/
static int nvhost_pod_init(struct devfreq *df)
{
struct podgov_info_rec *podgov;
struct platform_device *d = to_platform_device(df->dev.parent);
ktime_t now = ktime_get();
int error = 0;
struct nvhost_devfreq_ext_stat *ext_stat;
struct devfreq_dev_status dev_stat;
int stat = 0;
podgov = kzalloc(sizeof(struct podgov_info_rec), GFP_KERNEL);
if (!podgov)
goto err_alloc_podgov;
df->data = (void *)podgov;
/* Initialise workers */
INIT_DELAYED_WORK(&podgov->idle_timer, podgov_idle_handler);
/* Set scaling parameter defaults */
podgov->enable = 1;
podgov->block = 0;
podgov->p_use_throughput_hint = 1;
if (!strcmp(d->name, "vic03")) {
podgov->p_load_max = 990;
podgov->p_load_target = 800;
podgov->p_bias = 80;
podgov->p_hint_lo_limit = 500;
podgov->p_hint_hi_limit = 997;
podgov->p_scaleup_limit = 1100;
podgov->p_scaledown_limit = 1300;
podgov->p_smooth = 10;
podgov->p_smooth_long = 10;
podgov->p_damp = 7;
} else {
podgov->p_load_max = 900;
podgov->p_load_target = 500;
podgov->p_bias = 80;
podgov->p_hint_lo_limit = 500;
podgov->p_hint_hi_limit = 997;
podgov->p_scaleup_limit = 1100;
podgov->p_scaledown_limit = 1300;
podgov->p_smooth = 10;
podgov->p_smooth_long = 40;
podgov->p_damp = 7;
}
podgov->p_slowdown_delay = 10;
podgov->p_block_window = 50000;
podgov->adjustment_type = ADJUSTMENT_DEVICE_REQ;
podgov->p_user = 0;
/* Reset clock counters */
podgov->last_throughput_hint = now;
podgov->last_scale = now;
podgov->last_freq_estimate = now;
podgov->power_manager = df;
/* Get the current status of the device */
stat = df->profile->get_dev_status(df->dev.parent, &dev_stat);
if (!dev_stat.private_data) {
pr_err("podgov: device does not support ext_stat.\n");
goto err_get_current_status;
}
ext_stat = dev_stat.private_data;
/* store the limits */
df->min_freq = ext_stat->min_freq;
df->max_freq = ext_stat->max_freq;
podgov->p_freq_request = ext_stat->max_freq;
/* Create sysfs entries for controlling this governor */
error = device_create_file(&d->dev,
&dev_attr_enable_3d_scaling);
if (error)
goto err_create_sysfs_entry;
error = device_create_file(&d->dev,
&dev_attr_user);
if (error)
goto err_create_sysfs_entry;
error = device_create_file(&d->dev,
&dev_attr_freq_request);
if (error)
goto err_create_sysfs_entry;
podgov->freq_count = df->profile->max_state;
podgov->freqlist = df->profile->freq_table;
if (!podgov->freq_count || !podgov->freqlist)
goto err_get_freqs;
podgov->idle_avg_short = 0;
podgov->idle_avg_long = 0;
podgov->freq_avg = 0;
podgov->hint_avg = 0;
nvhost_scale3d_debug_init(df);
#ifdef CONFIG_TEGRA_THROUGHPUT
/* register the governor to throughput hint notifier chain */
podgov->throughput_hint_notifier.notifier_call =
&nvhost_scale3d_set_throughput_hint;
blocking_notifier_chain_register(&throughput_notifier_list,
&podgov->throughput_hint_notifier);
#endif
return 0;
err_get_freqs:
device_remove_file(&d->dev, &dev_attr_enable_3d_scaling);
device_remove_file(&d->dev, &dev_attr_user);
device_remove_file(&d->dev, &dev_attr_freq_request);
err_create_sysfs_entry:
dev_err(&d->dev, "failed to create sysfs attributes");
err_get_current_status:
kfree(podgov);
err_alloc_podgov:
return -ENOMEM;
}
/*******************************************************************************
* nvhost_pod_exit(struct devfreq *df)
*
* Clean up governor data structures
******************************************************************************/
static void nvhost_pod_exit(struct devfreq *df)
{
struct podgov_info_rec *podgov = df->data;
struct platform_device *d = to_platform_device(df->dev.parent);
#ifdef CONFIG_TEGRA_THROUGHPUT
blocking_notifier_chain_unregister(&throughput_notifier_list,
&podgov->throughput_hint_notifier);
#endif
cancel_delayed_work(&podgov->idle_timer);
device_remove_file(&d->dev, &dev_attr_enable_3d_scaling);
device_remove_file(&d->dev, &dev_attr_user);
device_remove_file(&d->dev, &dev_attr_freq_request);
nvhost_scale3d_debug_deinit(df);
kfree(podgov);
}
static int nvhost_pod_event_handler(struct devfreq *df,
unsigned int event, void *data)
{
int ret = 0;
switch (event) {
case DEVFREQ_GOV_START:
ret = nvhost_pod_init(df);
break;
case DEVFREQ_GOV_STOP:
nvhost_pod_exit(df);
break;
default:
break;
}
return ret;
}
static struct devfreq_governor nvhost_podgov = {
.name = "nvhost_podgov",
.get_target_freq = nvhost_pod_estimate_freq,
.event_handler = nvhost_pod_event_handler,
};
static int __init podgov_init(void)
{
return devfreq_add_governor(&nvhost_podgov);
}
static void __exit podgov_exit(void)
{
devfreq_remove_governor(&nvhost_podgov);
}
/* governor must be registered before initialising client devices */
rootfs_initcall(podgov_init);
module_exit(podgov_exit);