1 // SPDX-License-Identifier: GPL-2.0 2 /* 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 control 8 * for generic opp core to handle devices with ABB regulator and/or 9 * 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 table 27 * @reference_uv: reference voltage (usually Nominal voltage) 28 * @optimized_uv: Optimized voltage from efuse 29 */ 30 struct 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 data 37 * @vdd_table: Optimized voltage mapping table 38 * @num_vdd_table: number of entries in vdd_table 39 * @vdd_absolute_max_voltage_uv: absolute maximum voltage in UV for the supply 40 * @old_supplies: Placeholder for supplies information for old OPP. 41 * @new_supplies: Placeholder for supplies information for new OPP. 42 */ 43 struct 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 51 static struct ti_opp_supply_data opp_data; 52 53 /** 54 * struct ti_opp_supply_of_data - device tree match data 55 * @flags: specific type of opp supply 56 * @efuse_voltage_mask: mask required for efuse register representing voltage 57 * @efuse_voltage_uv: Are the efuse entries in micro-volts? if not, assume 58 * milli-volts. 59 */ 60 struct 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 voltages 70 * @dev: ti opp supply device for which we need to store info 71 * @data: data specific to the device 72 * 73 * Picks up efuse based optimized voltages for VDD unique per device and 74 * stores it in internal data structure for use during transition requests. 75 * 76 * Return: If successful, 0, else appropriate error value. 77 */ 78 static 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 efuse 159 * Use reference voltage for those - just add debug message 160 * 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 } 168 out: 169 iounmap(base); 170 out_map: 171 return ret; 172 } 173 174 /** 175 * _free_optimized_voltages() - free resources for optvoltages 176 * @dev: device for which we need to free info 177 * @data: data specific to the device 178 */ 179 static 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 supply 189 * @dev: device for which we need to find info 190 * @data: data specific to the device 191 * @reference_uv: reference voltage (OPP voltage) for which we need value 192 * 193 * Return: if a match is found, return optimized voltage, else return 194 * reference_uv, also return reference_uv if no optimization is needed. 195 */ 196 static 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 } 220 221 static 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 else 232 vdd_uv = supply->u_volt; 233 234 /* 235 * If we do have an absolute max voltage specified, then we should 236 * use that voltage instead to allow for cases where the voltage rails 237 * are ganged (example if we set the max for an opp as 1.12v, and 238 * the absolute max is 1.5v, for another rail to get 1.25v, it cannot 239 * be achieved if the regulator is constrainted to max of 1.12v, even 240 * if it can function at 1.25v 241 */ 242 if (opp_data.vdd_absolute_max_voltage_uv) 243 uv_max = opp_data.vdd_absolute_max_voltage_uv; 244 else 245 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 */ 275 static 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; 328 329 restore_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 } 348 349 static const struct ti_opp_supply_of_data omap_generic_of_data = { 350 }; 351 352 static 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 }; 357 358 static 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 }; 363 364 static 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 }; 371 MODULE_DEVICE_TABLE(of, ti_opp_supply_of_match); 372 373 static 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 } 403 404 static 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 }; 411 module_platform_driver(ti_opp_supply_driver); 412 413 MODULE_DESCRIPTION("Texas Instruments OMAP OPP Supply driver"); 414 MODULE_AUTHOR("Texas Instruments Inc."); 415 MODULE_LICENSE("GPL v2"); 416