|  | // SPDX-License-Identifier: GPL-2.0 | 
|  | /* | 
|  | * Copyright (C) 2016-2017 Texas Instruments Incorporated - https://www.ti.com/ | 
|  | *	Nishanth Menon <nm@ti.com> | 
|  | *	Dave Gerlach <d-gerlach@ti.com> | 
|  | * | 
|  | * 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(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 = kcalloc(data->num_vdd_table, sizeof(*data->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. | 
|  | */ | 
|  | static 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_vdd->u_volt); | 
|  |  | 
|  | if (new_supply_vdd->u_volt_min < vdd_uv) | 
|  | new_supply_vdd->u_volt_min = vdd_uv; | 
|  |  | 
|  | /* 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", | 
|  | .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"); |