linux-zen-server/drivers/soc/samsung/exynos-asv.c

161 lines
3.5 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2019 Samsung Electronics Co., Ltd.
* http://www.samsung.com/
* Copyright (c) 2020 Krzysztof Kozlowski <krzk@kernel.org>
* Author: Sylwester Nawrocki <s.nawrocki@samsung.com>
* Author: Krzysztof Kozlowski <krzk@kernel.org>
*
* Samsung Exynos SoC Adaptive Supply Voltage support
*/
#include <linux/cpu.h>
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/of.h>
#include <linux/pm_opp.h>
#include <linux/regmap.h>
#include <linux/soc/samsung/exynos-chipid.h>
#include "exynos-asv.h"
#include "exynos5422-asv.h"
#define MHZ 1000000U
static int exynos_asv_update_cpu_opps(struct exynos_asv *asv,
struct device *cpu)
{
struct exynos_asv_subsys *subsys = NULL;
struct dev_pm_opp *opp;
unsigned int opp_freq;
int i;
for (i = 0; i < ARRAY_SIZE(asv->subsys); i++) {
if (of_device_is_compatible(cpu->of_node,
asv->subsys[i].cpu_dt_compat)) {
subsys = &asv->subsys[i];
break;
}
}
if (!subsys)
return -EINVAL;
for (i = 0; i < subsys->table.num_rows; i++) {
unsigned int new_volt, volt;
int ret;
opp_freq = exynos_asv_opp_get_frequency(subsys, i);
opp = dev_pm_opp_find_freq_exact(cpu, opp_freq * MHZ, true);
if (IS_ERR(opp)) {
dev_info(asv->dev, "cpu%d opp%d, freq: %u missing\n",
cpu->id, i, opp_freq);
continue;
}
volt = dev_pm_opp_get_voltage(opp);
new_volt = asv->opp_get_voltage(subsys, i, volt);
dev_pm_opp_put(opp);
if (new_volt == volt)
continue;
ret = dev_pm_opp_adjust_voltage(cpu, opp_freq * MHZ,
new_volt, new_volt, new_volt);
if (ret < 0)
dev_err(asv->dev,
"Failed to adjust OPP %u Hz/%u uV for cpu%d\n",
opp_freq, new_volt, cpu->id);
else
dev_dbg(asv->dev,
"Adjusted OPP %u Hz/%u -> %u uV, cpu%d\n",
opp_freq, volt, new_volt, cpu->id);
}
return 0;
}
static int exynos_asv_update_opps(struct exynos_asv *asv)
{
struct opp_table *last_opp_table = NULL;
struct device *cpu;
int ret, cpuid;
for_each_possible_cpu(cpuid) {
struct opp_table *opp_table;
cpu = get_cpu_device(cpuid);
if (!cpu)
continue;
opp_table = dev_pm_opp_get_opp_table(cpu);
if (IS_ERR(opp_table))
continue;
if (!last_opp_table || opp_table != last_opp_table) {
last_opp_table = opp_table;
ret = exynos_asv_update_cpu_opps(asv, cpu);
if (ret < 0)
dev_err(asv->dev, "Couldn't udate OPPs for cpu%d\n",
cpuid);
}
dev_pm_opp_put_opp_table(opp_table);
}
return 0;
}
int exynos_asv_init(struct device *dev, struct regmap *regmap)
{
int (*probe_func)(struct exynos_asv *asv);
struct exynos_asv *asv;
struct device *cpu_dev;
u32 product_id = 0;
int ret, i;
asv = devm_kzalloc(dev, sizeof(*asv), GFP_KERNEL);
if (!asv)
return -ENOMEM;
asv->chipid_regmap = regmap;
asv->dev = dev;
ret = regmap_read(asv->chipid_regmap, EXYNOS_CHIPID_REG_PRO_ID,
&product_id);
if (ret < 0) {
dev_err(dev, "Cannot read revision from ChipID: %d\n", ret);
return -ENODEV;
}
switch (product_id & EXYNOS_MASK) {
case 0xE5422000:
probe_func = exynos5422_asv_init;
break;
default:
dev_dbg(dev, "No ASV support for this SoC\n");
devm_kfree(dev, asv);
return 0;
}
cpu_dev = get_cpu_device(0);
ret = dev_pm_opp_get_opp_count(cpu_dev);
if (ret < 0)
return -EPROBE_DEFER;
ret = of_property_read_u32(dev->of_node, "samsung,asv-bin",
&asv->of_bin);
if (ret < 0)
asv->of_bin = -EINVAL;
for (i = 0; i < ARRAY_SIZE(asv->subsys); i++)
asv->subsys[i].asv = asv;
ret = probe_func(asv);
if (ret < 0)
return ret;
return exynos_asv_update_opps(asv);
}