1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * R-Car Gen3 THS thermal sensor driver 4 * Based on rcar_thermal.c and work from Hien Dang and Khiem Nguyen. 5 * 6 * Copyright (C) 2016 Renesas Electronics Corporation. 7 * Copyright (C) 2016 Sang Engineering 8 */ 9 #include <linux/delay.h> 10 #include <linux/err.h> 11 #include <linux/interrupt.h> 12 #include <linux/io.h> 13 #include <linux/module.h> 14 #include <linux/of_device.h> 15 #include <linux/platform_device.h> 16 #include <linux/pm_runtime.h> 17 #include <linux/thermal.h> 18 19 #include "thermal_hwmon.h" 20 21 /* Register offsets */ 22 #define REG_GEN3_IRQSTR 0x04 23 #define REG_GEN3_IRQMSK 0x08 24 #define REG_GEN3_IRQCTL 0x0C 25 #define REG_GEN3_IRQEN 0x10 26 #define REG_GEN3_IRQTEMP1 0x14 27 #define REG_GEN3_IRQTEMP2 0x18 28 #define REG_GEN3_IRQTEMP3 0x1C 29 #define REG_GEN3_THCTR 0x20 30 #define REG_GEN3_TEMP 0x28 31 #define REG_GEN3_THCODE1 0x50 32 #define REG_GEN3_THCODE2 0x54 33 #define REG_GEN3_THCODE3 0x58 34 #define REG_GEN3_PTAT1 0x5c 35 #define REG_GEN3_PTAT2 0x60 36 #define REG_GEN3_PTAT3 0x64 37 #define REG_GEN3_THSCP 0x68 38 39 /* IRQ{STR,MSK,EN} bits */ 40 #define IRQ_TEMP1 BIT(0) 41 #define IRQ_TEMP2 BIT(1) 42 #define IRQ_TEMP3 BIT(2) 43 #define IRQ_TEMPD1 BIT(3) 44 #define IRQ_TEMPD2 BIT(4) 45 #define IRQ_TEMPD3 BIT(5) 46 47 /* THCTR bits */ 48 #define THCTR_PONM BIT(6) 49 #define THCTR_THSST BIT(0) 50 51 /* THSCP bits */ 52 #define THSCP_COR_PARA_VLD (BIT(15) | BIT(14)) 53 54 #define CTEMP_MASK 0xFFF 55 56 #define MCELSIUS(temp) ((temp) * 1000) 57 #define GEN3_FUSE_MASK 0xFFF 58 59 #define TSC_MAX_NUM 5 60 61 /* Structure for thermal temperature calculation */ 62 struct equation_coefs { 63 int a1; 64 int b1; 65 int a2; 66 int b2; 67 }; 68 69 struct rcar_gen3_thermal_tsc { 70 void __iomem *base; 71 struct thermal_zone_device *zone; 72 struct equation_coefs coef; 73 int tj_t; 74 int thcode[3]; 75 }; 76 77 struct rcar_gen3_thermal_priv { 78 struct rcar_gen3_thermal_tsc *tscs[TSC_MAX_NUM]; 79 struct thermal_zone_device_ops ops; 80 unsigned int num_tscs; 81 int ptat[3]; 82 }; 83 84 static inline u32 rcar_gen3_thermal_read(struct rcar_gen3_thermal_tsc *tsc, 85 u32 reg) 86 { 87 return ioread32(tsc->base + reg); 88 } 89 90 static inline void rcar_gen3_thermal_write(struct rcar_gen3_thermal_tsc *tsc, 91 u32 reg, u32 data) 92 { 93 iowrite32(data, tsc->base + reg); 94 } 95 96 /* 97 * Linear approximation for temperature 98 * 99 * [reg] = [temp] * a + b => [temp] = ([reg] - b) / a 100 * 101 * The constants a and b are calculated using two triplets of int values PTAT 102 * and THCODE. PTAT and THCODE can either be read from hardware or use hard 103 * coded values from driver. The formula to calculate a and b are taken from 104 * BSP and sparsely documented and understood. 105 * 106 * Examining the linear formula and the formula used to calculate constants a 107 * and b while knowing that the span for PTAT and THCODE values are between 108 * 0x000 and 0xfff the largest integer possible is 0xfff * 0xfff == 0xffe001. 109 * Integer also needs to be signed so that leaves 7 bits for binary 110 * fixed point scaling. 111 */ 112 113 #define FIXPT_SHIFT 7 114 #define FIXPT_INT(_x) ((_x) << FIXPT_SHIFT) 115 #define INT_FIXPT(_x) ((_x) >> FIXPT_SHIFT) 116 #define FIXPT_DIV(_a, _b) DIV_ROUND_CLOSEST(((_a) << FIXPT_SHIFT), (_b)) 117 #define FIXPT_TO_MCELSIUS(_x) ((_x) * 1000 >> FIXPT_SHIFT) 118 119 #define RCAR3_THERMAL_GRAN 500 /* mili Celsius */ 120 121 /* no idea where these constants come from */ 122 #define TJ_3 -41 123 124 static void rcar_gen3_thermal_calc_coefs(struct rcar_gen3_thermal_priv *priv, 125 struct rcar_gen3_thermal_tsc *tsc, 126 int ths_tj_1) 127 { 128 /* TODO: Find documentation and document constant calculation formula */ 129 130 /* 131 * Division is not scaled in BSP and if scaled it might overflow 132 * the dividend (4095 * 4095 << 14 > INT_MAX) so keep it unscaled 133 */ 134 tsc->tj_t = (FIXPT_INT((priv->ptat[1] - priv->ptat[2]) * (ths_tj_1 - TJ_3)) 135 / (priv->ptat[0] - priv->ptat[2])) + FIXPT_INT(TJ_3); 136 137 tsc->coef.a1 = FIXPT_DIV(FIXPT_INT(tsc->thcode[1] - tsc->thcode[2]), 138 tsc->tj_t - FIXPT_INT(TJ_3)); 139 tsc->coef.b1 = FIXPT_INT(tsc->thcode[2]) - tsc->coef.a1 * TJ_3; 140 141 tsc->coef.a2 = FIXPT_DIV(FIXPT_INT(tsc->thcode[1] - tsc->thcode[0]), 142 tsc->tj_t - FIXPT_INT(ths_tj_1)); 143 tsc->coef.b2 = FIXPT_INT(tsc->thcode[0]) - tsc->coef.a2 * ths_tj_1; 144 } 145 146 static int rcar_gen3_thermal_round(int temp) 147 { 148 int result, round_offs; 149 150 round_offs = temp >= 0 ? RCAR3_THERMAL_GRAN / 2 : 151 -RCAR3_THERMAL_GRAN / 2; 152 result = (temp + round_offs) / RCAR3_THERMAL_GRAN; 153 return result * RCAR3_THERMAL_GRAN; 154 } 155 156 static int rcar_gen3_thermal_get_temp(struct thermal_zone_device *tz, int *temp) 157 { 158 struct rcar_gen3_thermal_tsc *tsc = thermal_zone_device_priv(tz); 159 int mcelsius, val; 160 int reg; 161 162 /* Read register and convert to mili Celsius */ 163 reg = rcar_gen3_thermal_read(tsc, REG_GEN3_TEMP) & CTEMP_MASK; 164 165 if (reg <= tsc->thcode[1]) 166 val = FIXPT_DIV(FIXPT_INT(reg) - tsc->coef.b1, 167 tsc->coef.a1); 168 else 169 val = FIXPT_DIV(FIXPT_INT(reg) - tsc->coef.b2, 170 tsc->coef.a2); 171 mcelsius = FIXPT_TO_MCELSIUS(val); 172 173 /* Guaranteed operating range is -40C to 125C. */ 174 175 /* Round value to device granularity setting */ 176 *temp = rcar_gen3_thermal_round(mcelsius); 177 178 return 0; 179 } 180 181 static int rcar_gen3_thermal_mcelsius_to_temp(struct rcar_gen3_thermal_tsc *tsc, 182 int mcelsius) 183 { 184 int celsius, val; 185 186 celsius = DIV_ROUND_CLOSEST(mcelsius, 1000); 187 if (celsius <= INT_FIXPT(tsc->tj_t)) 188 val = celsius * tsc->coef.a1 + tsc->coef.b1; 189 else 190 val = celsius * tsc->coef.a2 + tsc->coef.b2; 191 192 return INT_FIXPT(val); 193 } 194 195 static int rcar_gen3_thermal_set_trips(struct thermal_zone_device *tz, int low, int high) 196 { 197 struct rcar_gen3_thermal_tsc *tsc = thermal_zone_device_priv(tz); 198 u32 irqmsk = 0; 199 200 if (low != -INT_MAX) { 201 irqmsk |= IRQ_TEMPD1; 202 rcar_gen3_thermal_write(tsc, REG_GEN3_IRQTEMP1, 203 rcar_gen3_thermal_mcelsius_to_temp(tsc, low)); 204 } 205 206 if (high != INT_MAX) { 207 irqmsk |= IRQ_TEMP2; 208 rcar_gen3_thermal_write(tsc, REG_GEN3_IRQTEMP2, 209 rcar_gen3_thermal_mcelsius_to_temp(tsc, high)); 210 } 211 212 rcar_gen3_thermal_write(tsc, REG_GEN3_IRQMSK, irqmsk); 213 214 return 0; 215 } 216 217 static const struct thermal_zone_device_ops rcar_gen3_tz_of_ops = { 218 .get_temp = rcar_gen3_thermal_get_temp, 219 .set_trips = rcar_gen3_thermal_set_trips, 220 }; 221 222 static irqreturn_t rcar_gen3_thermal_irq(int irq, void *data) 223 { 224 struct rcar_gen3_thermal_priv *priv = data; 225 unsigned int i; 226 u32 status; 227 228 for (i = 0; i < priv->num_tscs; i++) { 229 status = rcar_gen3_thermal_read(priv->tscs[i], REG_GEN3_IRQSTR); 230 rcar_gen3_thermal_write(priv->tscs[i], REG_GEN3_IRQSTR, 0); 231 if (status && priv->tscs[i]->zone) 232 thermal_zone_device_update(priv->tscs[i]->zone, 233 THERMAL_EVENT_UNSPECIFIED); 234 } 235 236 return IRQ_HANDLED; 237 } 238 239 static bool rcar_gen3_thermal_read_fuses(struct rcar_gen3_thermal_priv *priv) 240 { 241 unsigned int i; 242 u32 thscp; 243 244 /* If fuses are not set, fallback to pseudo values. */ 245 thscp = rcar_gen3_thermal_read(priv->tscs[0], REG_GEN3_THSCP); 246 if ((thscp & THSCP_COR_PARA_VLD) != THSCP_COR_PARA_VLD) { 247 /* Default THCODE values in case FUSEs are not set. */ 248 static const int thcodes[TSC_MAX_NUM][3] = { 249 { 3397, 2800, 2221 }, 250 { 3393, 2795, 2216 }, 251 { 3389, 2805, 2237 }, 252 { 3415, 2694, 2195 }, 253 { 3356, 2724, 2244 }, 254 }; 255 256 priv->ptat[0] = 2631; 257 priv->ptat[1] = 1509; 258 priv->ptat[2] = 435; 259 260 for (i = 0; i < priv->num_tscs; i++) { 261 struct rcar_gen3_thermal_tsc *tsc = priv->tscs[i]; 262 263 tsc->thcode[0] = thcodes[i][0]; 264 tsc->thcode[1] = thcodes[i][1]; 265 tsc->thcode[2] = thcodes[i][2]; 266 } 267 268 return false; 269 } 270 271 /* 272 * Set the pseudo calibration points with fused values. 273 * PTAT is shared between all TSCs but only fused for the first 274 * TSC while THCODEs are fused for each TSC. 275 */ 276 priv->ptat[0] = rcar_gen3_thermal_read(priv->tscs[0], REG_GEN3_PTAT1) & 277 GEN3_FUSE_MASK; 278 priv->ptat[1] = rcar_gen3_thermal_read(priv->tscs[0], REG_GEN3_PTAT2) & 279 GEN3_FUSE_MASK; 280 priv->ptat[2] = rcar_gen3_thermal_read(priv->tscs[0], REG_GEN3_PTAT3) & 281 GEN3_FUSE_MASK; 282 283 for (i = 0; i < priv->num_tscs; i++) { 284 struct rcar_gen3_thermal_tsc *tsc = priv->tscs[i]; 285 286 tsc->thcode[0] = rcar_gen3_thermal_read(tsc, REG_GEN3_THCODE1) & 287 GEN3_FUSE_MASK; 288 tsc->thcode[1] = rcar_gen3_thermal_read(tsc, REG_GEN3_THCODE2) & 289 GEN3_FUSE_MASK; 290 tsc->thcode[2] = rcar_gen3_thermal_read(tsc, REG_GEN3_THCODE3) & 291 GEN3_FUSE_MASK; 292 } 293 294 return true; 295 } 296 297 static void rcar_gen3_thermal_init(struct rcar_gen3_thermal_priv *priv, 298 struct rcar_gen3_thermal_tsc *tsc) 299 { 300 u32 reg_val; 301 302 reg_val = rcar_gen3_thermal_read(tsc, REG_GEN3_THCTR); 303 reg_val &= ~THCTR_PONM; 304 rcar_gen3_thermal_write(tsc, REG_GEN3_THCTR, reg_val); 305 306 usleep_range(1000, 2000); 307 308 rcar_gen3_thermal_write(tsc, REG_GEN3_IRQCTL, 0); 309 rcar_gen3_thermal_write(tsc, REG_GEN3_IRQMSK, 0); 310 if (priv->ops.set_trips) 311 rcar_gen3_thermal_write(tsc, REG_GEN3_IRQEN, 312 IRQ_TEMPD1 | IRQ_TEMP2); 313 314 reg_val = rcar_gen3_thermal_read(tsc, REG_GEN3_THCTR); 315 reg_val |= THCTR_THSST; 316 rcar_gen3_thermal_write(tsc, REG_GEN3_THCTR, reg_val); 317 318 usleep_range(1000, 2000); 319 } 320 321 static const int rcar_gen3_ths_tj_1 = 126; 322 static const int rcar_gen3_ths_tj_1_m3_w = 116; 323 static const struct of_device_id rcar_gen3_thermal_dt_ids[] = { 324 { 325 .compatible = "renesas,r8a774a1-thermal", 326 .data = &rcar_gen3_ths_tj_1_m3_w, 327 }, 328 { 329 .compatible = "renesas,r8a774b1-thermal", 330 .data = &rcar_gen3_ths_tj_1, 331 }, 332 { 333 .compatible = "renesas,r8a774e1-thermal", 334 .data = &rcar_gen3_ths_tj_1, 335 }, 336 { 337 .compatible = "renesas,r8a7795-thermal", 338 .data = &rcar_gen3_ths_tj_1, 339 }, 340 { 341 .compatible = "renesas,r8a7796-thermal", 342 .data = &rcar_gen3_ths_tj_1_m3_w, 343 }, 344 { 345 .compatible = "renesas,r8a77961-thermal", 346 .data = &rcar_gen3_ths_tj_1_m3_w, 347 }, 348 { 349 .compatible = "renesas,r8a77965-thermal", 350 .data = &rcar_gen3_ths_tj_1, 351 }, 352 { 353 .compatible = "renesas,r8a77980-thermal", 354 .data = &rcar_gen3_ths_tj_1, 355 }, 356 { 357 .compatible = "renesas,r8a779a0-thermal", 358 .data = &rcar_gen3_ths_tj_1, 359 }, 360 { 361 .compatible = "renesas,r8a779f0-thermal", 362 .data = &rcar_gen3_ths_tj_1, 363 }, 364 { 365 .compatible = "renesas,r8a779g0-thermal", 366 .data = &rcar_gen3_ths_tj_1, 367 }, 368 {}, 369 }; 370 MODULE_DEVICE_TABLE(of, rcar_gen3_thermal_dt_ids); 371 372 static int rcar_gen3_thermal_remove(struct platform_device *pdev) 373 { 374 struct device *dev = &pdev->dev; 375 376 pm_runtime_put(dev); 377 pm_runtime_disable(dev); 378 379 return 0; 380 } 381 382 static void rcar_gen3_hwmon_action(void *data) 383 { 384 struct thermal_zone_device *zone = data; 385 386 thermal_remove_hwmon_sysfs(zone); 387 } 388 389 static int rcar_gen3_thermal_request_irqs(struct rcar_gen3_thermal_priv *priv, 390 struct platform_device *pdev) 391 { 392 struct device *dev = &pdev->dev; 393 unsigned int i; 394 char *irqname; 395 int ret, irq; 396 397 for (i = 0; i < 2; i++) { 398 irq = platform_get_irq_optional(pdev, i); 399 if (irq < 0) 400 return irq; 401 402 irqname = devm_kasprintf(dev, GFP_KERNEL, "%s:ch%d", 403 dev_name(dev), i); 404 if (!irqname) 405 return -ENOMEM; 406 407 ret = devm_request_threaded_irq(dev, irq, NULL, 408 rcar_gen3_thermal_irq, 409 IRQF_ONESHOT, irqname, priv); 410 if (ret) 411 return ret; 412 } 413 414 return 0; 415 } 416 417 static int rcar_gen3_thermal_probe(struct platform_device *pdev) 418 { 419 struct rcar_gen3_thermal_priv *priv; 420 struct device *dev = &pdev->dev; 421 const int *ths_tj_1 = of_device_get_match_data(dev); 422 struct resource *res; 423 struct thermal_zone_device *zone; 424 unsigned int i; 425 int ret; 426 427 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); 428 if (!priv) 429 return -ENOMEM; 430 431 priv->ops = rcar_gen3_tz_of_ops; 432 433 platform_set_drvdata(pdev, priv); 434 435 if (rcar_gen3_thermal_request_irqs(priv, pdev)) 436 priv->ops.set_trips = NULL; 437 438 pm_runtime_enable(dev); 439 pm_runtime_get_sync(dev); 440 441 for (i = 0; i < TSC_MAX_NUM; i++) { 442 struct rcar_gen3_thermal_tsc *tsc; 443 444 res = platform_get_resource(pdev, IORESOURCE_MEM, i); 445 if (!res) 446 break; 447 448 tsc = devm_kzalloc(dev, sizeof(*tsc), GFP_KERNEL); 449 if (!tsc) { 450 ret = -ENOMEM; 451 goto error_unregister; 452 } 453 454 tsc->base = devm_ioremap_resource(dev, res); 455 if (IS_ERR(tsc->base)) { 456 ret = PTR_ERR(tsc->base); 457 goto error_unregister; 458 } 459 460 priv->tscs[i] = tsc; 461 } 462 463 priv->num_tscs = i; 464 465 if (!rcar_gen3_thermal_read_fuses(priv)) 466 dev_info(dev, "No calibration values fused, fallback to driver values\n"); 467 468 for (i = 0; i < priv->num_tscs; i++) { 469 struct rcar_gen3_thermal_tsc *tsc = priv->tscs[i]; 470 471 rcar_gen3_thermal_init(priv, tsc); 472 rcar_gen3_thermal_calc_coefs(priv, tsc, *ths_tj_1); 473 474 zone = devm_thermal_of_zone_register(dev, i, tsc, &priv->ops); 475 if (IS_ERR(zone)) { 476 dev_err(dev, "Sensor %u: Can't register thermal zone\n", i); 477 ret = PTR_ERR(zone); 478 goto error_unregister; 479 } 480 tsc->zone = zone; 481 482 ret = thermal_add_hwmon_sysfs(tsc->zone); 483 if (ret) 484 goto error_unregister; 485 486 ret = devm_add_action_or_reset(dev, rcar_gen3_hwmon_action, zone); 487 if (ret) 488 goto error_unregister; 489 490 ret = thermal_zone_get_num_trips(tsc->zone); 491 if (ret < 0) 492 goto error_unregister; 493 494 dev_info(dev, "Sensor %u: Loaded %d trip points\n", i, ret); 495 } 496 497 if (!priv->num_tscs) { 498 ret = -ENODEV; 499 goto error_unregister; 500 } 501 502 return 0; 503 504 error_unregister: 505 rcar_gen3_thermal_remove(pdev); 506 507 return ret; 508 } 509 510 static int __maybe_unused rcar_gen3_thermal_resume(struct device *dev) 511 { 512 struct rcar_gen3_thermal_priv *priv = dev_get_drvdata(dev); 513 unsigned int i; 514 515 for (i = 0; i < priv->num_tscs; i++) { 516 struct rcar_gen3_thermal_tsc *tsc = priv->tscs[i]; 517 518 rcar_gen3_thermal_init(priv, tsc); 519 } 520 521 return 0; 522 } 523 524 static SIMPLE_DEV_PM_OPS(rcar_gen3_thermal_pm_ops, NULL, 525 rcar_gen3_thermal_resume); 526 527 static struct platform_driver rcar_gen3_thermal_driver = { 528 .driver = { 529 .name = "rcar_gen3_thermal", 530 .pm = &rcar_gen3_thermal_pm_ops, 531 .of_match_table = rcar_gen3_thermal_dt_ids, 532 }, 533 .probe = rcar_gen3_thermal_probe, 534 .remove = rcar_gen3_thermal_remove, 535 }; 536 module_platform_driver(rcar_gen3_thermal_driver); 537 538 MODULE_LICENSE("GPL v2"); 539 MODULE_DESCRIPTION("R-Car Gen3 THS thermal sensor driver"); 540 MODULE_AUTHOR("Wolfram Sang <wsa+renesas@sang-engineering.com>"); 541