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1// SPDX-License-Identifier: GPL-2.02/*3 * Copyright (C) 2016-2017 Texas Instruments Incorporated - https://www.ti.com/4 * Nishanth Menon <nm@ti.com>5 * Dave Gerlach <d-gerlach@ti.com>6 *7 * TI OPP supply driver that provides override into the regulator control8 * for generic opp core to handle devices with ABB regulator and/or9 * SmartReflex Class0.10 */11#include <linux/clk.h>12#include <linux/cpufreq.h>13#include <linux/device.h>14#include <linux/io.h>15#include <linux/module.h>16#include <linux/notifier.h>17#include <linux/of_device.h>18#include <linux/of.h>19#include <linux/platform_device.h>20#include <linux/pm_opp.h>21#include <linux/property.h>22#include <linux/regulator/consumer.h>23#include <linux/slab.h>24 25/**26 * struct ti_opp_supply_optimum_voltage_table - optimized voltage table27 * @reference_uv: reference voltage (usually Nominal voltage)28 * @optimized_uv: Optimized voltage from efuse29 */30struct ti_opp_supply_optimum_voltage_table {31 unsigned int reference_uv;32 unsigned int optimized_uv;33};34 35/**36 * struct ti_opp_supply_data - OMAP specific opp supply data37 * @vdd_table: Optimized voltage mapping table38 * @num_vdd_table: number of entries in vdd_table39 * @vdd_absolute_max_voltage_uv: absolute maximum voltage in UV for the supply40 * @old_supplies: Placeholder for supplies information for old OPP.41 * @new_supplies: Placeholder for supplies information for new OPP.42 */43struct ti_opp_supply_data {44 struct ti_opp_supply_optimum_voltage_table *vdd_table;45 u32 num_vdd_table;46 u32 vdd_absolute_max_voltage_uv;47 struct dev_pm_opp_supply old_supplies[2];48 struct dev_pm_opp_supply new_supplies[2];49};50 51static struct ti_opp_supply_data opp_data;52 53/**54 * struct ti_opp_supply_of_data - device tree match data55 * @flags: specific type of opp supply56 * @efuse_voltage_mask: mask required for efuse register representing voltage57 * @efuse_voltage_uv: Are the efuse entries in micro-volts? if not, assume58 * milli-volts.59 */60struct ti_opp_supply_of_data {61#define OPPDM_EFUSE_CLASS0_OPTIMIZED_VOLTAGE BIT(1)62#define OPPDM_HAS_NO_ABB BIT(2)63 const u8 flags;64 const u32 efuse_voltage_mask;65 const bool efuse_voltage_uv;66};67 68/**69 * _store_optimized_voltages() - store optimized voltages70 * @dev: ti opp supply device for which we need to store info71 * @data: data specific to the device72 *73 * Picks up efuse based optimized voltages for VDD unique per device and74 * stores it in internal data structure for use during transition requests.75 *76 * Return: If successful, 0, else appropriate error value.77 */78static int _store_optimized_voltages(struct device *dev,79 struct ti_opp_supply_data *data)80{81 void __iomem *base;82 struct property *prop;83 struct resource *res;84 const __be32 *val;85 int proplen, i;86 int ret = 0;87 struct ti_opp_supply_optimum_voltage_table *table;88 const struct ti_opp_supply_of_data *of_data = dev_get_drvdata(dev);89 90 /* pick up Efuse based voltages */91 res = platform_get_resource(to_platform_device(dev), IORESOURCE_MEM, 0);92 if (!res) {93 dev_err(dev, "Unable to get IO resource\n");94 ret = -ENODEV;95 goto out_map;96 }97 98 base = ioremap(res->start, resource_size(res));99 if (!base) {100 dev_err(dev, "Unable to map Efuse registers\n");101 ret = -ENOMEM;102 goto out_map;103 }104 105 /* Fetch efuse-settings. */106 prop = of_find_property(dev->of_node, "ti,efuse-settings", NULL);107 if (!prop) {108 dev_err(dev, "No 'ti,efuse-settings' property found\n");109 ret = -EINVAL;110 goto out;111 }112 113 proplen = prop->length / sizeof(int);114 data->num_vdd_table = proplen / 2;115 /* Verify for corrupted OPP entries in dt */116 if (data->num_vdd_table * 2 * sizeof(int) != prop->length) {117 dev_err(dev, "Invalid 'ti,efuse-settings'\n");118 ret = -EINVAL;119 goto out;120 }121 122 ret = of_property_read_u32(dev->of_node, "ti,absolute-max-voltage-uv",123 &data->vdd_absolute_max_voltage_uv);124 if (ret) {125 dev_err(dev, "ti,absolute-max-voltage-uv is missing\n");126 ret = -EINVAL;127 goto out;128 }129 130 table = kcalloc(data->num_vdd_table, sizeof(*data->vdd_table),131 GFP_KERNEL);132 if (!table) {133 ret = -ENOMEM;134 goto out;135 }136 data->vdd_table = table;137 138 val = prop->value;139 for (i = 0; i < data->num_vdd_table; i++, table++) {140 u32 efuse_offset;141 u32 tmp;142 143 table->reference_uv = be32_to_cpup(val++);144 efuse_offset = be32_to_cpup(val++);145 146 tmp = readl(base + efuse_offset);147 tmp &= of_data->efuse_voltage_mask;148 tmp >>= __ffs(of_data->efuse_voltage_mask);149 150 table->optimized_uv = of_data->efuse_voltage_uv ? tmp :151 tmp * 1000;152 153 dev_dbg(dev, "[%d] efuse=0x%08x volt_table=%d vset=%d\n",154 i, efuse_offset, table->reference_uv,155 table->optimized_uv);156 157 /*158 * Some older samples might not have optimized efuse159 * Use reference voltage for those - just add debug message160 * for them.161 */162 if (!table->optimized_uv) {163 dev_dbg(dev, "[%d] efuse=0x%08x volt_table=%d:vset0\n",164 i, efuse_offset, table->reference_uv);165 table->optimized_uv = table->reference_uv;166 }167 }168out:169 iounmap(base);170out_map:171 return ret;172}173 174/**175 * _free_optimized_voltages() - free resources for optvoltages176 * @dev: device for which we need to free info177 * @data: data specific to the device178 */179static void _free_optimized_voltages(struct device *dev,180 struct ti_opp_supply_data *data)181{182 kfree(data->vdd_table);183 data->vdd_table = NULL;184 data->num_vdd_table = 0;185}186 187/**188 * _get_optimal_vdd_voltage() - Finds optimal voltage for the supply189 * @dev: device for which we need to find info190 * @data: data specific to the device191 * @reference_uv: reference voltage (OPP voltage) for which we need value192 *193 * Return: if a match is found, return optimized voltage, else return194 * reference_uv, also return reference_uv if no optimization is needed.195 */196static int _get_optimal_vdd_voltage(struct device *dev,197 struct ti_opp_supply_data *data,198 int reference_uv)199{200 int i;201 struct ti_opp_supply_optimum_voltage_table *table;202 203 if (!data->num_vdd_table)204 return reference_uv;205 206 table = data->vdd_table;207 if (!table)208 return -EINVAL;209 210 /* Find a exact match - this list is usually very small */211 for (i = 0; i < data->num_vdd_table; i++, table++)212 if (table->reference_uv == reference_uv)213 return table->optimized_uv;214 215 /* IF things are screwed up, we'd make a mess on console.. ratelimit */216 dev_err_ratelimited(dev, "%s: Failed optimized voltage match for %d\n",217 __func__, reference_uv);218 return reference_uv;219}220 221static int _opp_set_voltage(struct device *dev,222 struct dev_pm_opp_supply *supply,223 int new_target_uv, struct regulator *reg,224 char *reg_name)225{226 int ret;227 unsigned long vdd_uv, uv_max;228 229 if (new_target_uv)230 vdd_uv = new_target_uv;231 else232 vdd_uv = supply->u_volt;233 234 /*235 * If we do have an absolute max voltage specified, then we should236 * use that voltage instead to allow for cases where the voltage rails237 * are ganged (example if we set the max for an opp as 1.12v, and238 * the absolute max is 1.5v, for another rail to get 1.25v, it cannot239 * be achieved if the regulator is constrainted to max of 1.12v, even240 * if it can function at 1.25v241 */242 if (opp_data.vdd_absolute_max_voltage_uv)243 uv_max = opp_data.vdd_absolute_max_voltage_uv;244 else245 uv_max = supply->u_volt_max;246 247 if (vdd_uv > uv_max ||248 vdd_uv < supply->u_volt_min ||249 supply->u_volt_min > uv_max) {250 dev_warn(dev,251 "Invalid range voltages [Min:%lu target:%lu Max:%lu]\n",252 supply->u_volt_min, vdd_uv, uv_max);253 return -EINVAL;254 }255 256 dev_dbg(dev, "%s scaling to %luuV[min %luuV max %luuV]\n", reg_name,257 vdd_uv, supply->u_volt_min,258 uv_max);259 260 ret = regulator_set_voltage_triplet(reg,261 supply->u_volt_min,262 vdd_uv,263 uv_max);264 if (ret) {265 dev_err(dev, "%s failed for %luuV[min %luuV max %luuV]\n",266 reg_name, vdd_uv, supply->u_volt_min,267 uv_max);268 return ret;269 }270 271 return 0;272}273 274/* Do the opp supply transition */275static int ti_opp_config_regulators(struct device *dev,276 struct dev_pm_opp *old_opp, struct dev_pm_opp *new_opp,277 struct regulator **regulators, unsigned int count)278{279 struct dev_pm_opp_supply *old_supply_vdd = &opp_data.old_supplies[0];280 struct dev_pm_opp_supply *old_supply_vbb = &opp_data.old_supplies[1];281 struct dev_pm_opp_supply *new_supply_vdd = &opp_data.new_supplies[0];282 struct dev_pm_opp_supply *new_supply_vbb = &opp_data.new_supplies[1];283 struct regulator *vdd_reg = regulators[0];284 struct regulator *vbb_reg = regulators[1];285 unsigned long old_freq, freq;286 int vdd_uv;287 int ret;288 289 /* We must have two regulators here */290 WARN_ON(count != 2);291 292 /* Fetch supplies and freq information from OPP core */293 ret = dev_pm_opp_get_supplies(new_opp, opp_data.new_supplies);294 WARN_ON(ret);295 296 old_freq = dev_pm_opp_get_freq(old_opp);297 freq = dev_pm_opp_get_freq(new_opp);298 WARN_ON(!old_freq || !freq);299 300 vdd_uv = _get_optimal_vdd_voltage(dev, &opp_data,301 new_supply_vdd->u_volt);302 303 if (new_supply_vdd->u_volt_min < vdd_uv)304 new_supply_vdd->u_volt_min = vdd_uv;305 306 /* Scaling up? Scale voltage before frequency */307 if (freq > old_freq) {308 ret = _opp_set_voltage(dev, new_supply_vdd, vdd_uv, vdd_reg,309 "vdd");310 if (ret)311 goto restore_voltage;312 313 ret = _opp_set_voltage(dev, new_supply_vbb, 0, vbb_reg, "vbb");314 if (ret)315 goto restore_voltage;316 } else {317 ret = _opp_set_voltage(dev, new_supply_vbb, 0, vbb_reg, "vbb");318 if (ret)319 goto restore_voltage;320 321 ret = _opp_set_voltage(dev, new_supply_vdd, vdd_uv, vdd_reg,322 "vdd");323 if (ret)324 goto restore_voltage;325 }326 327 return 0;328 329restore_voltage:330 /* Fetch old supplies information only if required */331 ret = dev_pm_opp_get_supplies(old_opp, opp_data.old_supplies);332 WARN_ON(ret);333 334 /* This shouldn't harm even if the voltages weren't updated earlier */335 if (old_supply_vdd->u_volt) {336 ret = _opp_set_voltage(dev, old_supply_vbb, 0, vbb_reg, "vbb");337 if (ret)338 return ret;339 340 ret = _opp_set_voltage(dev, old_supply_vdd, 0, vdd_reg,341 "vdd");342 if (ret)343 return ret;344 }345 346 return ret;347}348 349static const struct ti_opp_supply_of_data omap_generic_of_data = {350};351 352static const struct ti_opp_supply_of_data omap_omap5_of_data = {353 .flags = OPPDM_EFUSE_CLASS0_OPTIMIZED_VOLTAGE,354 .efuse_voltage_mask = 0xFFF,355 .efuse_voltage_uv = false,356};357 358static const struct ti_opp_supply_of_data omap_omap5core_of_data = {359 .flags = OPPDM_EFUSE_CLASS0_OPTIMIZED_VOLTAGE | OPPDM_HAS_NO_ABB,360 .efuse_voltage_mask = 0xFFF,361 .efuse_voltage_uv = false,362};363 364static const struct of_device_id ti_opp_supply_of_match[] = {365 {.compatible = "ti,omap-opp-supply", .data = &omap_generic_of_data},366 {.compatible = "ti,omap5-opp-supply", .data = &omap_omap5_of_data},367 {.compatible = "ti,omap5-core-opp-supply",368 .data = &omap_omap5core_of_data},369 {},370};371MODULE_DEVICE_TABLE(of, ti_opp_supply_of_match);372 373static int ti_opp_supply_probe(struct platform_device *pdev)374{375 struct device *dev = &pdev->dev;376 struct device *cpu_dev = get_cpu_device(0);377 const struct ti_opp_supply_of_data *of_data;378 int ret = 0;379 380 of_data = device_get_match_data(dev);381 if (!of_data) {382 /* Again, unlikely.. but mistakes do happen */383 dev_err(dev, "%s: Bad data in match\n", __func__);384 return -EINVAL;385 }386 dev_set_drvdata(dev, (void *)of_data);387 388 /* If we need optimized voltage */389 if (of_data->flags & OPPDM_EFUSE_CLASS0_OPTIMIZED_VOLTAGE) {390 ret = _store_optimized_voltages(dev, &opp_data);391 if (ret)392 return ret;393 }394 395 ret = dev_pm_opp_set_config_regulators(cpu_dev, ti_opp_config_regulators);396 if (ret < 0) {397 _free_optimized_voltages(dev, &opp_data);398 return ret;399 }400 401 return 0;402}403 404static struct platform_driver ti_opp_supply_driver = {405 .probe = ti_opp_supply_probe,406 .driver = {407 .name = "ti_opp_supply",408 .of_match_table = ti_opp_supply_of_match,409 },410};411module_platform_driver(ti_opp_supply_driver);412 413MODULE_DESCRIPTION("Texas Instruments OMAP OPP Supply driver");414MODULE_AUTHOR("Texas Instruments Inc.");415MODULE_LICENSE("GPL v2");416