blob: 8a836d92e54246bbd944c31a6a930fc9191a12bb [file] [log] [blame]
/*
* Copyright (c) 2013-2014, 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.
*/
#define pr_fmt(fmt) "devbw: " fmt
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/delay.h>
#include <linux/ktime.h>
#include <linux/time.h>
#include <linux/err.h>
#include <linux/errno.h>
#include <linux/mutex.h>
#include <linux/interrupt.h>
#include <linux/devfreq.h>
#include <linux/of.h>
#include <trace/events/power.h>
#include <linux/msm-bus.h>
#include <linux/msm-bus-board.h>
/* Has to be ULL to prevent overflow where this macro is used. */
#define MBYTE (1ULL << 20)
#define MAX_PATHS 2
#define DBL_BUF 2
struct dev_data {
struct msm_bus_vectors vectors[MAX_PATHS * DBL_BUF];
struct msm_bus_paths bw_levels[DBL_BUF];
struct msm_bus_scale_pdata bw_data;
int num_paths;
u32 bus_client;
int cur_idx;
int cur_ab;
int cur_ib;
long gov_ab;
unsigned int ab_percent;
struct devfreq *df;
struct devfreq_dev_profile dp;
};
static int set_bw(struct device *dev, int new_ib, int new_ab)
{
struct dev_data *d = dev_get_drvdata(dev);
int i, ret;
if (d->cur_ib == new_ib && d->cur_ab == new_ab)
return 0;
i = (d->cur_idx + 1) % DBL_BUF;
d->bw_levels[i].vectors[0].ib = new_ib * MBYTE;
d->bw_levels[i].vectors[0].ab = new_ab / d->num_paths * MBYTE;
d->bw_levels[i].vectors[1].ib = new_ib * MBYTE;
d->bw_levels[i].vectors[1].ab = new_ab / d->num_paths * MBYTE;
dev_dbg(dev, "BW MBps: AB: %d IB: %d\n", new_ab, new_ib);
ret = msm_bus_scale_client_update_request(d->bus_client, i);
if (ret) {
dev_err(dev, "bandwidth request failed (%d)\n", ret);
} else {
d->cur_idx = i;
d->cur_ib = new_ib;
d->cur_ab = new_ab;
}
return ret;
}
static unsigned int find_ab(struct dev_data *d, unsigned long *freq)
{
return (d->ab_percent * (*freq)) / 100;
}
static void find_freq(struct devfreq_dev_profile *p, unsigned long *freq,
u32 flags)
{
int i;
unsigned long atmost, atleast, f;
atmost = p->freq_table[0];
atleast = p->freq_table[p->max_state-1];
for (i = 0; i < p->max_state; i++) {
f = p->freq_table[i];
if (f <= *freq)
atmost = max(f, atmost);
if (f >= *freq)
atleast = min(f, atleast);
}
if (flags & DEVFREQ_FLAG_LEAST_UPPER_BOUND)
*freq = atmost;
else
*freq = atleast;
}
static int devbw_target(struct device *dev, unsigned long *freq, u32 flags)
{
struct dev_data *d = dev_get_drvdata(dev);
find_freq(&d->dp, freq, flags);
if (!d->gov_ab)
return set_bw(dev, *freq, find_ab(d, freq));
else
return set_bw(dev, *freq, d->gov_ab);
}
static int devbw_get_dev_status(struct device *dev,
struct devfreq_dev_status *stat)
{
struct dev_data *d = dev_get_drvdata(dev);
stat->private_data = &d->gov_ab;
return 0;
}
#define PROP_PORTS "qcom,src-dst-ports"
#define PROP_TBL "qcom,bw-tbl"
#define PROP_AB_PER "qcom,ab-percent"
#define PROP_ACTIVE "qcom,active-only"
int devfreq_add_devbw(struct device *dev)
{
struct dev_data *d;
struct devfreq_dev_profile *p;
u32 *data, ports[MAX_PATHS * 2];
const char *gov_name;
int ret, len, i, num_paths;
d = devm_kzalloc(dev, sizeof(*d), GFP_KERNEL);
if (!d)
return -ENOMEM;
dev_set_drvdata(dev, d);
if (of_find_property(dev->of_node, PROP_PORTS, &len)) {
len /= sizeof(ports[0]);
if (len % 2 || len > ARRAY_SIZE(ports)) {
dev_err(dev, "Unexpected number of ports\n");
return -EINVAL;
}
ret = of_property_read_u32_array(dev->of_node, PROP_PORTS,
ports, len);
if (ret)
return ret;
num_paths = len / 2;
} else {
return -EINVAL;
}
d->bw_levels[0].vectors = &d->vectors[0];
d->bw_levels[1].vectors = &d->vectors[MAX_PATHS];
d->bw_data.usecase = d->bw_levels;
d->bw_data.num_usecases = ARRAY_SIZE(d->bw_levels);
d->bw_data.name = dev_name(dev);
d->bw_data.active_only = of_property_read_bool(dev->of_node,
PROP_ACTIVE);
for (i = 0; i < num_paths; i++) {
d->bw_levels[0].vectors[i].src = ports[2 * i];
d->bw_levels[0].vectors[i].dst = ports[2 * i + 1];
d->bw_levels[1].vectors[i].src = ports[2 * i];
d->bw_levels[1].vectors[i].dst = ports[2 * i + 1];
}
d->bw_levels[0].num_paths = num_paths;
d->bw_levels[1].num_paths = num_paths;
d->num_paths = num_paths;
p = &d->dp;
p->polling_ms = 50;
p->target = devbw_target;
p->get_dev_status = devbw_get_dev_status;
if (of_find_property(dev->of_node, PROP_TBL, &len)) {
len /= sizeof(*data);
data = devm_kzalloc(dev, len * sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
p->freq_table = devm_kzalloc(dev,
len * sizeof(*p->freq_table),
GFP_KERNEL);
if (!p->freq_table)
return -ENOMEM;
ret = of_property_read_u32_array(dev->of_node, PROP_TBL,
data, len);
if (ret)
return ret;
for (i = 0; i < len; i++)
p->freq_table[i] = data[i];
p->max_state = len;
}
if (of_find_property(dev->of_node, PROP_AB_PER, &len)) {
ret = of_property_read_u32(dev->of_node, PROP_AB_PER,
&d->ab_percent);
if (ret)
return ret;
dev_dbg(dev, "ab-percent used %u\n", d->ab_percent);
}
d->bus_client = msm_bus_scale_register_client(&d->bw_data);
if (!d->bus_client) {
dev_err(dev, "Unable to register bus client\n");
return -ENODEV;
}
if (of_property_read_string(dev->of_node, "governor", &gov_name))
gov_name = "performance";
d->df = devfreq_add_device(dev, p, gov_name, NULL);
if (IS_ERR(d->df)) {
msm_bus_scale_unregister_client(d->bus_client);
return PTR_ERR(d->df);
}
return 0;
}
int devfreq_remove_devbw(struct device *dev)
{
struct dev_data *d = dev_get_drvdata(dev);
msm_bus_scale_unregister_client(d->bus_client);
devfreq_remove_device(d->df);
return 0;
}
int devfreq_suspend_devbw(struct device *dev)
{
struct dev_data *d = dev_get_drvdata(dev);
return devfreq_suspend_device(d->df);
}
int devfreq_resume_devbw(struct device *dev)
{
struct dev_data *d = dev_get_drvdata(dev);
return devfreq_resume_device(d->df);
}
static int devfreq_devbw_probe(struct platform_device *pdev)
{
return devfreq_add_devbw(&pdev->dev);
}
static int devfreq_devbw_remove(struct platform_device *pdev)
{
return devfreq_remove_devbw(&pdev->dev);
}
static struct of_device_id match_table[] = {
{ .compatible = "qcom,devbw" },
{}
};
static struct platform_driver devbw_driver = {
.probe = devfreq_devbw_probe,
.remove = devfreq_devbw_remove,
.driver = {
.name = "devbw",
.of_match_table = match_table,
.owner = THIS_MODULE,
},
};
static int __init devbw_init(void)
{
platform_driver_register(&devbw_driver);
return 0;
}
device_initcall(devbw_init);
MODULE_DESCRIPTION("Device DDR bandwidth voting driver MSM SoCs");
MODULE_LICENSE("GPL v2");