blob: d8a50bfc6c742a7461e18045a17170033085daf2 [file] [log] [blame]
/* Copyright (c) 2014, The Linux Foundation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
* only version 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that 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.
*
*/
#include <linux/devfreq.h>
#include <linux/module.h>
#include <linux/msm_adreno_devfreq.h>
#include "devfreq_trace.h"
#include "governor.h"
#define MIN_BUSY 1000
#define LONG_FLOOR 50000
#define HIST 5
#define TARGET 80
#define CAP 75
static void _update_cutoff(struct devfreq_msm_adreno_tz_data *priv,
unsigned int norm_max)
{
int i;
priv->bus.max = norm_max;
for (i = 0; i < priv->bus.num; i++) {
priv->bus.up[i] = priv->bus.p_up[i] * norm_max / 100;
priv->bus.down[i] = priv->bus.p_down[i] * norm_max / 100;
}
}
static int devfreq_gpubw_get_target(struct devfreq *df,
unsigned long *freq,
u32 *flag)
{
struct devfreq_msm_adreno_tz_data *priv = df->data;
struct msm_busmon_extended_profile *bus_profile = container_of(
(df->profile),
struct msm_busmon_extended_profile,
profile);
struct devfreq_dev_status stats;
struct xstats b;
int result;
int level = 0;
int act_level;
int norm_cycles;
int gpu_percent;
/*
* Normalized AB should at max usage be the gpu_bimc frequency in MHz.
* Start with a reasonable value and let the system push it up to max.
*/
static int norm_ab_max = 300;
int norm_ab;
stats.private_data = &b;
result = df->profile->get_dev_status(df->dev.parent, &stats);
*freq = stats.current_frequency;
priv->bus.total_time += stats.total_time;
priv->bus.gpu_time += stats.busy_time;
priv->bus.ram_time += b.ram_time;
priv->bus.ram_wait += b.ram_wait;
level = devfreq_get_freq_level(df, stats.current_frequency);
if (priv->bus.total_time < LONG_FLOOR)
return result;
norm_cycles = (unsigned int)(priv->bus.ram_time + priv->bus.ram_wait) /
(unsigned int) priv->bus.total_time;
gpu_percent = (100 * (unsigned int)priv->bus.gpu_time) /
(unsigned int) priv->bus.total_time;
/*
* If there's a new high watermark, update the cutoffs and send the
* FAST hint. Otherwise check the current value against the current
* cutoffs.
*/
if (norm_cycles > priv->bus.max) {
_update_cutoff(priv, norm_cycles);
bus_profile->flag = DEVFREQ_FLAG_FAST_HINT;
} else {
/* GPU votes for IB not AB so don't under vote the system */
norm_cycles = (100 * norm_cycles) / TARGET;
act_level = priv->bus.index[level] + b.mod;
act_level = (act_level < 0) ? 0 : act_level;
act_level = (act_level >= priv->bus.num) ?
(priv->bus.num - 1) : act_level;
if (norm_cycles > priv->bus.up[act_level] &&
gpu_percent > CAP)
bus_profile->flag = DEVFREQ_FLAG_FAST_HINT;
else if (norm_cycles < priv->bus.down[act_level] && level)
bus_profile->flag = DEVFREQ_FLAG_SLOW_HINT;
}
/* Re-calculate the AB percentage for a new IB vote */
if (bus_profile->flag) {
norm_ab = (unsigned int)priv->bus.ram_time /
(unsigned int) priv->bus.total_time;
if (norm_ab > norm_ab_max)
norm_ab_max = norm_ab;
bus_profile->percent_ab = (100 * norm_ab) / norm_ab_max;
}
priv->bus.total_time = 0;
priv->bus.gpu_time = 0;
priv->bus.ram_time = 0;
priv->bus.ram_wait = 0;
return result;
}
static int gpubw_start(struct devfreq *devfreq)
{
struct devfreq_msm_adreno_tz_data *priv;
struct msm_busmon_extended_profile *bus_profile = container_of(
(devfreq->profile),
struct msm_busmon_extended_profile,
profile);
unsigned int t1, t2 = 2 * HIST;
int i;
devfreq->data = bus_profile->private_data;
priv = devfreq->data;
/* Set up the cut-over percentages for the bus calculation. */
for (i = 0; i < priv->bus.num; i++) {
t1 = (u32)(100 * priv->bus.ib[i]) /
(u32)priv->bus.ib[priv->bus.num - 1];
priv->bus.p_up[i] = t1 - HIST;
priv->bus.p_down[i] = t2 - 2 * HIST;
t2 = t1;
}
/* Set the upper-most and lower-most bounds correctly. */
priv->bus.p_down[0] = 0;
priv->bus.p_down[1] = (priv->bus.p_down[1] > (2 * HIST)) ?
priv->bus.p_down[1] : (2 * HIST);
if (priv->bus.num >= 1)
priv->bus.p_up[priv->bus.num - 1] = 100;
_update_cutoff(priv, priv->bus.max);
return 0;
}
static int gpubw_stop(struct devfreq *devfreq)
{
devfreq->data = NULL;
return 0;
}
static int devfreq_gpubw_event_handler(struct devfreq *devfreq,
unsigned int event, void *data)
{
int result = 0;
unsigned long freq;
mutex_lock(&devfreq->lock);
freq = devfreq->previous_freq;
switch (event) {
case DEVFREQ_GOV_START:
result = gpubw_start(devfreq);
break;
case DEVFREQ_GOV_STOP:
result = gpubw_stop(devfreq);
break;
case DEVFREQ_GOV_RESUME:
/* TODO ..... */
/* ret = update_devfreq(devfreq); */
break;
case DEVFREQ_GOV_SUSPEND:
{
struct devfreq_msm_adreno_tz_data *priv = devfreq->data;
priv->bus.total_time = 0;
priv->bus.gpu_time = 0;
priv->bus.ram_time = 0;
}
break;
default:
result = 0;
break;
}
mutex_unlock(&devfreq->lock);
return result;
}
static struct devfreq_governor devfreq_gpubw = {
.name = "gpubw_mon",
.get_target_freq = devfreq_gpubw_get_target,
.event_handler = devfreq_gpubw_event_handler,
};
static int __init devfreq_gpubw_init(void)
{
return devfreq_add_governor(&devfreq_gpubw);
}
subsys_initcall(devfreq_gpubw_init);
static void __exit devfreq_gpubw_exit(void)
{
int ret;
ret = devfreq_remove_governor(&devfreq_gpubw);
if (ret)
pr_err("%s: failed remove governor %d\n", __func__, ret);
return;
}
module_exit(devfreq_gpubw_exit);
MODULE_DESCRIPTION("GPU bus bandwidth voting driver. Uses VBIF counters");
MODULE_LICENSE("GPL v2");