linux/drivers/devfreq/mtk-cci-devfreq.c
Rob Herring 9027f2e797 PM / devfreq: Explicitly include correct DT includes
The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it as merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.

Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
2023-07-24 05:19:26 +09:00

445 lines
11 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2022 MediaTek Inc.
*/
#include <linux/clk.h>
#include <linux/devfreq.h>
#include <linux/minmax.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pm_opp.h>
#include <linux/regulator/consumer.h>
struct mtk_ccifreq_platform_data {
int min_volt_shift;
int max_volt_shift;
int proc_max_volt;
int sram_min_volt;
int sram_max_volt;
};
struct mtk_ccifreq_drv {
struct device *dev;
struct devfreq *devfreq;
struct regulator *proc_reg;
struct regulator *sram_reg;
struct clk *cci_clk;
struct clk *inter_clk;
int inter_voltage;
unsigned long pre_freq;
/* Avoid race condition for regulators between notify and policy */
struct mutex reg_lock;
struct notifier_block opp_nb;
const struct mtk_ccifreq_platform_data *soc_data;
int vtrack_max;
};
static int mtk_ccifreq_set_voltage(struct mtk_ccifreq_drv *drv, int new_voltage)
{
const struct mtk_ccifreq_platform_data *soc_data = drv->soc_data;
struct device *dev = drv->dev;
int pre_voltage, pre_vsram, new_vsram, vsram, voltage, ret;
int retry_max = drv->vtrack_max;
if (!drv->sram_reg) {
ret = regulator_set_voltage(drv->proc_reg, new_voltage,
drv->soc_data->proc_max_volt);
return ret;
}
pre_voltage = regulator_get_voltage(drv->proc_reg);
if (pre_voltage < 0) {
dev_err(dev, "invalid vproc value: %d\n", pre_voltage);
return pre_voltage;
}
pre_vsram = regulator_get_voltage(drv->sram_reg);
if (pre_vsram < 0) {
dev_err(dev, "invalid vsram value: %d\n", pre_vsram);
return pre_vsram;
}
new_vsram = clamp(new_voltage + soc_data->min_volt_shift,
soc_data->sram_min_volt, soc_data->sram_max_volt);
do {
if (pre_voltage <= new_voltage) {
vsram = clamp(pre_voltage + soc_data->max_volt_shift,
soc_data->sram_min_volt, new_vsram);
ret = regulator_set_voltage(drv->sram_reg, vsram,
soc_data->sram_max_volt);
if (ret)
return ret;
if (vsram == soc_data->sram_max_volt ||
new_vsram == soc_data->sram_min_volt)
voltage = new_voltage;
else
voltage = vsram - soc_data->min_volt_shift;
ret = regulator_set_voltage(drv->proc_reg, voltage,
soc_data->proc_max_volt);
if (ret) {
regulator_set_voltage(drv->sram_reg, pre_vsram,
soc_data->sram_max_volt);
return ret;
}
} else if (pre_voltage > new_voltage) {
voltage = max(new_voltage,
pre_vsram - soc_data->max_volt_shift);
ret = regulator_set_voltage(drv->proc_reg, voltage,
soc_data->proc_max_volt);
if (ret)
return ret;
if (voltage == new_voltage)
vsram = new_vsram;
else
vsram = max(new_vsram,
voltage + soc_data->min_volt_shift);
ret = regulator_set_voltage(drv->sram_reg, vsram,
soc_data->sram_max_volt);
if (ret) {
regulator_set_voltage(drv->proc_reg, pre_voltage,
soc_data->proc_max_volt);
return ret;
}
}
pre_voltage = voltage;
pre_vsram = vsram;
if (--retry_max < 0) {
dev_err(dev,
"over loop count, failed to set voltage\n");
return -EINVAL;
}
} while (voltage != new_voltage || vsram != new_vsram);
return 0;
}
static int mtk_ccifreq_target(struct device *dev, unsigned long *freq,
u32 flags)
{
struct mtk_ccifreq_drv *drv = dev_get_drvdata(dev);
struct clk *cci_pll;
struct dev_pm_opp *opp;
unsigned long opp_rate;
int voltage, pre_voltage, inter_voltage, target_voltage, ret;
if (!drv)
return -EINVAL;
if (drv->pre_freq == *freq)
return 0;
inter_voltage = drv->inter_voltage;
cci_pll = clk_get_parent(drv->cci_clk);
opp_rate = *freq;
opp = devfreq_recommended_opp(dev, &opp_rate, 1);
if (IS_ERR(opp)) {
dev_err(dev, "failed to find opp for freq: %ld\n", opp_rate);
return PTR_ERR(opp);
}
mutex_lock(&drv->reg_lock);
voltage = dev_pm_opp_get_voltage(opp);
dev_pm_opp_put(opp);
pre_voltage = regulator_get_voltage(drv->proc_reg);
if (pre_voltage < 0) {
dev_err(dev, "invalid vproc value: %d\n", pre_voltage);
ret = pre_voltage;
goto out_unlock;
}
/* scale up: set voltage first then freq. */
target_voltage = max(inter_voltage, voltage);
if (pre_voltage <= target_voltage) {
ret = mtk_ccifreq_set_voltage(drv, target_voltage);
if (ret) {
dev_err(dev, "failed to scale up voltage\n");
goto out_restore_voltage;
}
}
/* switch the cci clock to intermediate clock source. */
ret = clk_set_parent(drv->cci_clk, drv->inter_clk);
if (ret) {
dev_err(dev, "failed to re-parent cci clock\n");
goto out_restore_voltage;
}
/* set the original clock to target rate. */
ret = clk_set_rate(cci_pll, *freq);
if (ret) {
dev_err(dev, "failed to set cci pll rate: %d\n", ret);
clk_set_parent(drv->cci_clk, cci_pll);
goto out_restore_voltage;
}
/* switch the cci clock back to the original clock source. */
ret = clk_set_parent(drv->cci_clk, cci_pll);
if (ret) {
dev_err(dev, "failed to re-parent cci clock\n");
mtk_ccifreq_set_voltage(drv, inter_voltage);
goto out_unlock;
}
/*
* If the new voltage is lower than the intermediate voltage or the
* original voltage, scale down to the new voltage.
*/
if (voltage < inter_voltage || voltage < pre_voltage) {
ret = mtk_ccifreq_set_voltage(drv, voltage);
if (ret) {
dev_err(dev, "failed to scale down voltage\n");
goto out_unlock;
}
}
drv->pre_freq = *freq;
mutex_unlock(&drv->reg_lock);
return 0;
out_restore_voltage:
mtk_ccifreq_set_voltage(drv, pre_voltage);
out_unlock:
mutex_unlock(&drv->reg_lock);
return ret;
}
static int mtk_ccifreq_opp_notifier(struct notifier_block *nb,
unsigned long event, void *data)
{
struct dev_pm_opp *opp = data;
struct mtk_ccifreq_drv *drv;
unsigned long freq, volt;
drv = container_of(nb, struct mtk_ccifreq_drv, opp_nb);
if (event == OPP_EVENT_ADJUST_VOLTAGE) {
freq = dev_pm_opp_get_freq(opp);
mutex_lock(&drv->reg_lock);
/* current opp item is changed */
if (freq == drv->pre_freq) {
volt = dev_pm_opp_get_voltage(opp);
mtk_ccifreq_set_voltage(drv, volt);
}
mutex_unlock(&drv->reg_lock);
}
return 0;
}
static struct devfreq_dev_profile mtk_ccifreq_profile = {
.target = mtk_ccifreq_target,
};
static int mtk_ccifreq_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct mtk_ccifreq_drv *drv;
struct devfreq_passive_data *passive_data;
struct dev_pm_opp *opp;
unsigned long rate, opp_volt;
int ret;
drv = devm_kzalloc(dev, sizeof(*drv), GFP_KERNEL);
if (!drv)
return -ENOMEM;
drv->dev = dev;
drv->soc_data = (const struct mtk_ccifreq_platform_data *)
of_device_get_match_data(&pdev->dev);
mutex_init(&drv->reg_lock);
platform_set_drvdata(pdev, drv);
drv->cci_clk = devm_clk_get(dev, "cci");
if (IS_ERR(drv->cci_clk)) {
ret = PTR_ERR(drv->cci_clk);
return dev_err_probe(dev, ret, "failed to get cci clk\n");
}
drv->inter_clk = devm_clk_get(dev, "intermediate");
if (IS_ERR(drv->inter_clk)) {
ret = PTR_ERR(drv->inter_clk);
return dev_err_probe(dev, ret,
"failed to get intermediate clk\n");
}
drv->proc_reg = devm_regulator_get_optional(dev, "proc");
if (IS_ERR(drv->proc_reg)) {
ret = PTR_ERR(drv->proc_reg);
return dev_err_probe(dev, ret,
"failed to get proc regulator\n");
}
ret = regulator_enable(drv->proc_reg);
if (ret) {
dev_err(dev, "failed to enable proc regulator\n");
return ret;
}
drv->sram_reg = devm_regulator_get_optional(dev, "sram");
if (IS_ERR(drv->sram_reg)) {
ret = PTR_ERR(drv->sram_reg);
if (ret == -EPROBE_DEFER)
goto out_free_resources;
drv->sram_reg = NULL;
} else {
ret = regulator_enable(drv->sram_reg);
if (ret) {
dev_err(dev, "failed to enable sram regulator\n");
goto out_free_resources;
}
}
/*
* We assume min voltage is 0 and tracking target voltage using
* min_volt_shift for each iteration.
* The retry_max is 3 times of expected iteration count.
*/
drv->vtrack_max = 3 * DIV_ROUND_UP(max(drv->soc_data->sram_max_volt,
drv->soc_data->proc_max_volt),
drv->soc_data->min_volt_shift);
ret = clk_prepare_enable(drv->cci_clk);
if (ret)
goto out_free_resources;
ret = dev_pm_opp_of_add_table(dev);
if (ret) {
dev_err(dev, "failed to add opp table: %d\n", ret);
goto out_disable_cci_clk;
}
rate = clk_get_rate(drv->inter_clk);
opp = dev_pm_opp_find_freq_ceil(dev, &rate);
if (IS_ERR(opp)) {
ret = PTR_ERR(opp);
dev_err(dev, "failed to get intermediate opp: %d\n", ret);
goto out_remove_opp_table;
}
drv->inter_voltage = dev_pm_opp_get_voltage(opp);
dev_pm_opp_put(opp);
rate = U32_MAX;
opp = dev_pm_opp_find_freq_floor(drv->dev, &rate);
if (IS_ERR(opp)) {
dev_err(dev, "failed to get opp\n");
ret = PTR_ERR(opp);
goto out_remove_opp_table;
}
opp_volt = dev_pm_opp_get_voltage(opp);
dev_pm_opp_put(opp);
ret = mtk_ccifreq_set_voltage(drv, opp_volt);
if (ret) {
dev_err(dev, "failed to scale to highest voltage %lu in proc_reg\n",
opp_volt);
goto out_remove_opp_table;
}
passive_data = devm_kzalloc(dev, sizeof(*passive_data), GFP_KERNEL);
if (!passive_data) {
ret = -ENOMEM;
goto out_remove_opp_table;
}
passive_data->parent_type = CPUFREQ_PARENT_DEV;
drv->devfreq = devm_devfreq_add_device(dev, &mtk_ccifreq_profile,
DEVFREQ_GOV_PASSIVE,
passive_data);
if (IS_ERR(drv->devfreq)) {
ret = -EPROBE_DEFER;
dev_err(dev, "failed to add devfreq device: %ld\n",
PTR_ERR(drv->devfreq));
goto out_remove_opp_table;
}
drv->opp_nb.notifier_call = mtk_ccifreq_opp_notifier;
ret = dev_pm_opp_register_notifier(dev, &drv->opp_nb);
if (ret) {
dev_err(dev, "failed to register opp notifier: %d\n", ret);
goto out_remove_opp_table;
}
return 0;
out_remove_opp_table:
dev_pm_opp_of_remove_table(dev);
out_disable_cci_clk:
clk_disable_unprepare(drv->cci_clk);
out_free_resources:
if (regulator_is_enabled(drv->proc_reg))
regulator_disable(drv->proc_reg);
if (drv->sram_reg && regulator_is_enabled(drv->sram_reg))
regulator_disable(drv->sram_reg);
return ret;
}
static int mtk_ccifreq_remove(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct mtk_ccifreq_drv *drv;
drv = platform_get_drvdata(pdev);
dev_pm_opp_unregister_notifier(dev, &drv->opp_nb);
dev_pm_opp_of_remove_table(dev);
clk_disable_unprepare(drv->cci_clk);
regulator_disable(drv->proc_reg);
if (drv->sram_reg)
regulator_disable(drv->sram_reg);
return 0;
}
static const struct mtk_ccifreq_platform_data mt8183_platform_data = {
.min_volt_shift = 100000,
.max_volt_shift = 200000,
.proc_max_volt = 1150000,
};
static const struct mtk_ccifreq_platform_data mt8186_platform_data = {
.min_volt_shift = 100000,
.max_volt_shift = 250000,
.proc_max_volt = 1118750,
.sram_min_volt = 850000,
.sram_max_volt = 1118750,
};
static const struct of_device_id mtk_ccifreq_machines[] = {
{ .compatible = "mediatek,mt8183-cci", .data = &mt8183_platform_data },
{ .compatible = "mediatek,mt8186-cci", .data = &mt8186_platform_data },
{ },
};
MODULE_DEVICE_TABLE(of, mtk_ccifreq_machines);
static struct platform_driver mtk_ccifreq_platdrv = {
.probe = mtk_ccifreq_probe,
.remove = mtk_ccifreq_remove,
.driver = {
.name = "mtk-ccifreq",
.of_match_table = mtk_ccifreq_machines,
},
};
module_platform_driver(mtk_ccifreq_platdrv);
MODULE_DESCRIPTION("MediaTek CCI devfreq driver");
MODULE_AUTHOR("Jia-Wei Chang <jia-wei.chang@mediatek.com>");
MODULE_LICENSE("GPL v2");