kernel-fxtec-pro1x/drivers/devfreq/governor_bw_vbif.c
Harshdeep Dhatt 1f6bfc5a45 devfreq: Restrict gpu governors to gpu devfreq devices
These governors should fail if being set for any device
other than the gpu device. Do this by checking that the
devfreq device for which this governor is being set for
has the gpu device as it's parent device.

The vbif_bw governor immutable attribute is used
to restrict it being set for only gpu devfreq devices.
Because we don't intend to change the governor for
the devfreq devices which have this governor set as
default.

Change-Id: I391557c0d52a1f4ffba70e010401a0769587dea0
Signed-off-by: Harshdeep Dhatt <hdhatt@codeaurora.org>
2019-11-26 14:12:54 -07:00

144 lines
3 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2014-2019, The Linux Foundation. All rights reserved.
*/
#include <linux/devfreq.h>
#include <linux/module.h>
#include <linux/msm_adreno_devfreq.h>
#include "governor.h"
static getbw_func extern_get_bw;
static void *extern_get_bw_data;
unsigned long *dev_ab;
static unsigned long dev_ib;
DEFINE_MUTEX(df_lock);
static struct devfreq *df;
/*
* This function is 'get_target_freq' API for the governor.
* It just calls an external function that should be registered
* by KGSL driver to get and return a value for frequency.
*/
static int devfreq_vbif_get_freq(struct devfreq *df,
unsigned long *freq)
{
unsigned long ab, ib;
if (!extern_get_bw) {
*freq = 0;
return 0;
}
extern_get_bw(&ib, &ab, extern_get_bw_data);
dev_ib = ib;
*dev_ab = ab;
*freq = dev_ib;
return 0;
}
/*
* Registers a function to be used to request a frequency
* value from legacy vbif based bus bandwidth governor.
* This function is called by KGSL driver.
*/
void devfreq_vbif_register_callback(getbw_func func, void *data)
{
extern_get_bw = func;
extern_get_bw_data = data;
}
int devfreq_vbif_update_bw(void)
{
int ret = 0;
mutex_lock(&df_lock);
if (df) {
mutex_lock(&df->lock);
ret = update_devfreq(df);
mutex_unlock(&df->lock);
}
mutex_unlock(&df_lock);
return ret;
}
static int devfreq_vbif_ev_handler(struct devfreq *devfreq,
unsigned int event, void *data)
{
int ret;
struct devfreq_dev_status stat;
switch (event) {
case DEVFREQ_GOV_START:
mutex_lock(&df_lock);
df = devfreq;
if (df->profile->get_dev_status &&
!df->profile->get_dev_status(df->dev.parent, &stat) &&
stat.private_data)
dev_ab = stat.private_data;
else
pr_warn("Device doesn't take AB votes!\n");
mutex_unlock(&df_lock);
dev_ib = 0;
*dev_ab = 0;
ret = devfreq_vbif_update_bw();
if (ret) {
pr_err("Unable to update BW! Gov start failed!\n");
return ret;
}
/*
* Normally at this point governors start the polling with
* devfreq_monitor_start(df);
* This governor doesn't poll, but expect external calls
* of its devfreq_vbif_update_bw() function
*/
pr_debug("Enabled MSM VBIF governor\n");
break;
case DEVFREQ_GOV_STOP:
mutex_lock(&df_lock);
df = NULL;
mutex_unlock(&df_lock);
pr_debug("Disabled MSM VBIF governor\n");
break;
}
return 0;
}
static struct devfreq_governor devfreq_vbif = {
.name = "bw_vbif",
/* Restrict this governor to only gpu devfreq devices */
.immutable = 1,
.get_target_freq = devfreq_vbif_get_freq,
.event_handler = devfreq_vbif_ev_handler,
};
static int __init devfreq_vbif_init(void)
{
return devfreq_add_governor(&devfreq_vbif);
}
subsys_initcall(devfreq_vbif_init);
static void __exit devfreq_vbif_exit(void)
{
int ret;
ret = devfreq_remove_governor(&devfreq_vbif);
if (ret)
pr_err("%s: failed remove governor %d\n", __func__, ret);
}
module_exit(devfreq_vbif_exit);
MODULE_DESCRIPTION("VBIF based GPU bus BW voting governor");
MODULE_LICENSE("GPL v2");