[PATCH 4/4] PM / OPP: Add ti-opp-supply driver
Viresh Kumar
viresh.kumar at linaro.org
Wed Dec 13 20:34:32 PST 2017
On 13-12-17, 14:33, Dave Gerlach wrote:
> Introduce a ti-opp-supply driver that will use new multiple regulator
> support that is part of the OPP core This is needed on TI platforms like
> DRA7/AM57 in order to control both CPU regulator and Adaptive Body Bias
> (ABB) regulator. These regulators must be scaled in sequence during an
> OPP transition depending on whether or not the frequency is being scaled
> up or down.
>
> This driver also implements AVS Class0 for these parts by looking up the
> required values from registers in the SoC and programming adjusted
> optimal voltage values for each OPP.
>
> Signed-off-by: Dave Gerlach <d-gerlach at ti.com>
> ---
> drivers/opp/Makefile | 1 +
> drivers/opp/ti-opp-supply.c | 428 ++++++++++++++++++++++++++++++++++++++++++++
Why is this added as a separate driver and not part of the same ti-cpufreq.c
file?
> 2 files changed, 429 insertions(+)
> create mode 100644 drivers/opp/ti-opp-supply.c
>
> diff --git a/drivers/opp/Makefile b/drivers/opp/Makefile
> index e70ceb406fe9..6ce6aefacc81 100644
> --- a/drivers/opp/Makefile
> +++ b/drivers/opp/Makefile
> @@ -2,3 +2,4 @@ ccflags-$(CONFIG_DEBUG_DRIVER) := -DDEBUG
> obj-y += core.o cpu.o
> obj-$(CONFIG_OF) += of.o
> obj-$(CONFIG_DEBUG_FS) += debugfs.o
> +obj-$(CONFIG_ARM_TI_CPUFREQ) += ti-opp-supply.o
> diff --git a/drivers/opp/ti-opp-supply.c b/drivers/opp/ti-opp-supply.c
> new file mode 100644
> index 000000000000..73d795c90b79
> --- /dev/null
> +++ b/drivers/opp/ti-opp-supply.c
> @@ -0,0 +1,428 @@
> +/*
> + * Copyright (C) 2016-2017 Texas Instruments Incorporated - http://www.ti.com/
> + * Nishanth Menon <nm at ti.com>
> + * Dave Gerlach <d-gerlach at ti.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
Please use the new SPDX format for licenses.
> + * TI OPP supply driver that provides override into the regulator control
> + * for generic opp core to handle devices with ABB regulator and/or
> + * SmartReflex Class0.
> + */
> +#include <linux/clk.h>
> +#include <linux/cpufreq.h>
> +#include <linux/device.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/notifier.h>
> +#include <linux/of_device.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_opp.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/slab.h>
> +
> +/**
> + * struct ti_opp_supply_optimum_voltage_table - optimized voltage table
> + * @reference_uv: reference voltage (usually Nominal voltage)
> + * @optimized_uv: Optimized voltage from efuse
> + */
> +struct ti_opp_supply_optimum_voltage_table {
> + unsigned int reference_uv;
> + unsigned int optimized_uv;
> +};
> +
> +/**
> + * struct ti_opp_supply_data - OMAP specific opp supply data
> + * @vdd_table: Optimized voltage mapping table
> + * @num_vdd_table: number of entries in vdd_table
> + * @vdd_absolute_max_voltage_uv: absolute maximum voltage in UV for the supply
> + */
> +struct ti_opp_supply_data {
> + struct ti_opp_supply_optimum_voltage_table *vdd_table;
> + u32 num_vdd_table;
> + u32 vdd_absolute_max_voltage_uv;
> +};
> +
> +static struct ti_opp_supply_data opp_data;
> +
> +/**
> + * struct ti_opp_supply_of_data - device tree match data
> + * @flags: specific type of opp supply
> + * @efuse_voltage_mask: mask required for efuse register representing voltage
> + * @efuse_voltage_uv: Are the efuse entries in micro-volts? if not, assume
> + * milli-volts.
> + */
> +struct ti_opp_supply_of_data {
> +#define OPPDM_EFUSE_CLASS0_OPTIMIZED_VOLTAGE BIT(1)
> +#define OPPDM_HAS_NO_ABB BIT(2)
> + const u8 flags;
> + const u32 efuse_voltage_mask;
> + const bool efuse_voltage_uv;
> +};
> +
> +/**
> + * _store_optimized_voltages() - store optimized voltages
> + * @dev: ti opp supply device for which we need to store info
> + * @data: data specific to the device
> + *
> + * Picks up efuse based optimized voltages for VDD unique per device and
> + * stores it in internal data structure for use during transition requests.
> + *
> + * Return: If successful, 0, else appropriate error value.
> + */
> +static int _store_optimized_voltages(struct device *dev,
> + struct ti_opp_supply_data *data)
> +{
> + void __iomem *base;
> + struct property *prop;
> + struct resource *res;
> + const __be32 *val;
> + int proplen, i;
> + int ret = 0;
> + struct ti_opp_supply_optimum_voltage_table *table;
> + const struct ti_opp_supply_of_data *of_data = dev_get_drvdata(dev);
> +
> + /* pick up Efuse based voltages */
> + res = platform_get_resource(to_platform_device(dev), IORESOURCE_MEM, 0);
> + if (!res) {
> + dev_err(dev, "Unable to get IO resource\n");
> + ret = -ENODEV;
> + goto out_map;
> + }
> +
> + base = ioremap_nocache(res->start, resource_size(res));
> + if (!base) {
> + dev_err(dev, "Unable to map Efuse registers\n");
> + ret = -ENOMEM;
> + goto out_map;
> + }
> +
> + /* Fetch efuse-settings. */
> + prop = of_find_property(dev->of_node, "ti,efuse-settings", NULL);
> + if (!prop) {
> + dev_err(dev, "No 'ti,efuse-settings' property found\n");
> + ret = -EINVAL;
> + goto out;
> + }
> +
> + proplen = prop->length / sizeof(int);
> + data->num_vdd_table = proplen / 2;
> + /* Verify for corrupted OPP entries in dt */
> + if (data->num_vdd_table * 2 * sizeof(int) != prop->length) {
> + dev_err(dev, "Invalid 'ti,efuse-settings'\n");
> + ret = -EINVAL;
> + goto out;
> + }
> +
> + ret = of_property_read_u32(dev->of_node, "ti,absolute-max-voltage-uv",
> + &data->vdd_absolute_max_voltage_uv);
> + if (ret) {
> + dev_err(dev, "ti,absolute-max-voltage-uv is missing\n");
> + ret = -EINVAL;
> + goto out;
> + }
> +
> + table = kzalloc(sizeof(*data->vdd_table) *
> + data->num_vdd_table, GFP_KERNEL);
> + if (!table) {
> + ret = -ENOMEM;
> + goto out;
> + }
> + data->vdd_table = table;
> +
> + val = prop->value;
> + for (i = 0; i < data->num_vdd_table; i++, table++) {
> + u32 efuse_offset;
> + u32 tmp;
> +
> + table->reference_uv = be32_to_cpup(val++);
> + efuse_offset = be32_to_cpup(val++);
> +
> + tmp = readl(base + efuse_offset);
> + tmp &= of_data->efuse_voltage_mask;
> + tmp >>= __ffs(of_data->efuse_voltage_mask);
> +
> + table->optimized_uv = of_data->efuse_voltage_uv ? tmp :
> + tmp * 1000;
> +
> + dev_dbg(dev, "[%d] efuse=0x%08x volt_table=%d vset=%d\n",
> + i, efuse_offset, table->reference_uv,
> + table->optimized_uv);
> +
> + /*
> + * Some older samples might not have optimized efuse
> + * Use reference voltage for those - just add debug message
> + * for them.
> + */
> + if (!table->optimized_uv) {
> + dev_dbg(dev, "[%d] efuse=0x%08x volt_table=%d:vset0\n",
> + i, efuse_offset, table->reference_uv);
> + table->optimized_uv = table->reference_uv;
> + }
> + }
> +out:
> + iounmap(base);
> +out_map:
> + return ret;
> +}
> +
> +/**
> + * _free_optimized_voltages() - free resources for optvoltages
> + * @dev: device for which we need to free info
> + * @data: data specific to the device
> + */
> +static void _free_optimized_voltages(struct device *dev,
> + struct ti_opp_supply_data *data)
> +{
> + kfree(data->vdd_table);
> + data->vdd_table = NULL;
> + data->num_vdd_table = 0;
> +}
> +
> +/**
> + * _get_optimal_vdd_voltage() - Finds optimal voltage for the supply
> + * @dev: device for which we need to find info
> + * @data: data specific to the device
> + * @reference_uv: reference voltage (OPP voltage) for which we need value
> + *
> + * Return: if a match is found, return optimized voltage, else return
> + * reference_uv, also return reference_uv if no optimization is needed.
> + */
> +static int _get_optimal_vdd_voltage(struct device *dev,
> + struct ti_opp_supply_data *data,
> + int reference_uv)
> +{
> + int i;
> + struct ti_opp_supply_optimum_voltage_table *table;
> +
> + if (!data->num_vdd_table)
> + return reference_uv;
> +
> + table = data->vdd_table;
> + if (!table)
> + return -EINVAL;
> +
> + /* Find a exact match - this list is usually very small */
> + for (i = 0; i < data->num_vdd_table; i++, table++)
> + if (table->reference_uv == reference_uv)
> + return table->optimized_uv;
> +
> + /* IF things are screwed up, we'd make a mess on console.. ratelimit */
> + dev_err_ratelimited(dev, "%s: Failed optimized voltage match for %d\n",
> + __func__, reference_uv);
> + return reference_uv;
> +}
> +
> +static int _opp_set_voltage(struct device *dev,
> + struct dev_pm_opp_supply *supply,
> + int new_target_uv, struct regulator *reg,
> + char *reg_name)
> +{
> + int ret;
> + unsigned long vdd_uv, uv_max;
> +
> + if (new_target_uv)
> + vdd_uv = new_target_uv;
> + else
> + vdd_uv = supply->u_volt;
> +
> + /*
> + * If we do have an absolute max voltage specified, then we should
> + * use that voltage instead to allow for cases where the voltage rails
> + * are ganged (example if we set the max for an opp as 1.12v, and
> + * the absolute max is 1.5v, for another rail to get 1.25v, it cannot
> + * be achieved if the regulator is constrainted to max of 1.12v, even
> + * if it can function at 1.25v
> + */
> + if (opp_data.vdd_absolute_max_voltage_uv)
> + uv_max = opp_data.vdd_absolute_max_voltage_uv;
> + else
> + uv_max = supply->u_volt_max;
> +
> + if (vdd_uv > uv_max ||
> + vdd_uv < supply->u_volt_min ||
> + supply->u_volt_min > uv_max) {
> + dev_warn(dev,
> + "Invalid range voltages [Min:%lu target:%lu Max:%lu]\n",
> + supply->u_volt_min, vdd_uv, uv_max);
> + return -EINVAL;
> + }
> +
> + dev_dbg(dev, "%s scaling to %luuV[min %luuV max %luuV]\n", reg_name,
> + vdd_uv, supply->u_volt_min,
> + uv_max);
> +
> + ret = regulator_set_voltage_triplet(reg,
> + supply->u_volt_min,
> + vdd_uv,
> + uv_max);
> + if (ret) {
> + dev_err(dev, "%s failed for %luuV[min %luuV max %luuV]\n",
> + reg_name, vdd_uv, supply->u_volt_min,
> + uv_max);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +/**
> + * ti_opp_supply_set_opp() - do the opp supply transition
> + * @data: information on regulators and new and old opps provided by
> + * opp core to use in transition
> + *
> + * Return: If successful, 0, else appropriate error value.
> + */
> +int ti_opp_supply_set_opp(struct dev_pm_set_opp_data *data)
> +{
> + struct dev_pm_opp_supply *old_supply_vdd = &data->old_opp.supplies[0];
> + struct dev_pm_opp_supply *old_supply_vbb = &data->old_opp.supplies[1];
> + struct dev_pm_opp_supply *new_supply_vdd = &data->new_opp.supplies[0];
> + struct dev_pm_opp_supply *new_supply_vbb = &data->new_opp.supplies[1];
> + struct device *dev = data->dev;
> + unsigned long old_freq = data->old_opp.rate, freq = data->new_opp.rate;
> + struct clk *clk = data->clk;
> + struct regulator *vdd_reg = data->regulators[0];
> + struct regulator *vbb_reg = data->regulators[1];
> + int vdd_uv;
> + int ret;
> +
> + vdd_uv = _get_optimal_vdd_voltage(dev, &opp_data,
> + new_supply_vbb->u_volt);
> +
> + /* Scaling up? Scale voltage before frequency */
> + if (freq > old_freq) {
> + ret = _opp_set_voltage(dev, new_supply_vdd, vdd_uv, vdd_reg,
> + "vdd");
> + if (ret)
> + goto restore_voltage;
> +
> + ret = _opp_set_voltage(dev, new_supply_vbb, 0, vbb_reg, "vbb");
> + if (ret)
> + goto restore_voltage;
> + }
> +
> + /* Change frequency */
> + dev_dbg(dev, "%s: switching OPP: %lu Hz --> %lu Hz\n",
> + __func__, old_freq, freq);
> +
> + ret = clk_set_rate(clk, freq);
> + if (ret) {
> + dev_err(dev, "%s: failed to set clock rate: %d\n", __func__,
> + ret);
> + goto restore_voltage;
> + }
> +
> + /* Scaling down? Scale voltage after frequency */
> + if (freq < old_freq) {
> + ret = _opp_set_voltage(dev, new_supply_vbb, 0, vbb_reg, "vbb");
> + if (ret)
> + goto restore_freq;
> +
> + ret = _opp_set_voltage(dev, new_supply_vdd, vdd_uv, vdd_reg,
> + "vdd");
> + if (ret)
> + goto restore_freq;
> + }
> +
> + return 0;
> +
> +restore_freq:
> + ret = clk_set_rate(clk, old_freq);
> + if (ret)
> + dev_err(dev, "%s: failed to restore old-freq (%lu Hz)\n",
> + __func__, old_freq);
> +restore_voltage:
> + /* This shouldn't harm even if the voltages weren't updated earlier */
> + if (old_supply_vdd->u_volt) {
> + ret = _opp_set_voltage(dev, old_supply_vbb, 0, vbb_reg, "vbb");
> + if (ret)
> + return ret;
> +
> + ret = _opp_set_voltage(dev, old_supply_vdd, 0, vdd_reg,
> + "vdd");
> + if (ret)
> + return ret;
> + }
> +
> + return ret;
> +}
> +
> +static const struct ti_opp_supply_of_data omap_generic_of_data = {
> +};
> +
> +static const struct ti_opp_supply_of_data omap_omap5_of_data = {
> + .flags = OPPDM_EFUSE_CLASS0_OPTIMIZED_VOLTAGE,
> + .efuse_voltage_mask = 0xFFF,
> + .efuse_voltage_uv = false,
> +};
> +
> +static const struct ti_opp_supply_of_data omap_omap5core_of_data = {
> + .flags = OPPDM_EFUSE_CLASS0_OPTIMIZED_VOLTAGE | OPPDM_HAS_NO_ABB,
> + .efuse_voltage_mask = 0xFFF,
> + .efuse_voltage_uv = false,
> +};
> +
> +static const struct of_device_id ti_opp_supply_of_match[] = {
> + {.compatible = "ti,omap-opp-supply", .data = &omap_generic_of_data},
> + {.compatible = "ti,omap5-opp-supply", .data = &omap_omap5_of_data},
> + {.compatible = "ti,omap5-core-opp-supply",
> + .data = &omap_omap5core_of_data},
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, ti_opp_supply_of_match);
> +
> +static int ti_opp_supply_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct device *cpu_dev = get_cpu_device(0);
> + const struct of_device_id *match;
> + const struct ti_opp_supply_of_data *of_data;
> + int ret = 0;
> +
> + match = of_match_device(ti_opp_supply_of_match, dev);
> + if (!match) {
> + /* We do not expect this to happen */
> + dev_err(dev, "%s: Unable to match device\n", __func__);
> + return -ENODEV;
> + }
> + if (!match->data) {
> + /* Again, unlikely.. but mistakes do happen */
> + dev_err(dev, "%s: Bad data in match\n", __func__);
> + return -EINVAL;
> + }
> + of_data = match->data;
> +
> + dev_set_drvdata(dev, (void *)of_data);
> +
> + /* If we need optimized voltage */
> + if (of_data->flags & OPPDM_EFUSE_CLASS0_OPTIMIZED_VOLTAGE) {
> + ret = _store_optimized_voltages(dev, &opp_data);
> + if (ret)
> + return ret;
> + }
> +
> + ret = PTR_ERR_OR_ZERO(dev_pm_opp_register_set_opp_helper(cpu_dev,
> + ti_opp_supply_set_opp));
> + if (ret)
> + _free_optimized_voltages(dev, &opp_data);
> +
> + return ret;
> +}
> +
> +static struct platform_driver ti_opp_supply_driver = {
> + .probe = ti_opp_supply_probe,
> + .driver = {
> + .name = "ti_opp_supply",
> + .owner = THIS_MODULE,
> + .of_match_table = of_match_ptr(ti_opp_supply_of_match),
> + },
> +};
> +module_platform_driver(ti_opp_supply_driver);
> +
> +MODULE_DESCRIPTION("Texas Instruments OMAP OPP Supply driver");
> +MODULE_AUTHOR("Texas Instruments Inc.");
> +MODULE_LICENSE("GPL v2");
Looks fine otherwise.
--
viresh
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