drivers/thermal/broadcom/brcmstb_thermal.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Broadcom STB AVS TMON thermal sensor driver
   4  *
   5  * Copyright (c) 2015-2017 Broadcom
   6  */
   7
   8 #define DRV_NAME        "brcmstb_thermal"
   9
  10 #define pr_fmt(fmt)     DRV_NAME ": " fmt
  11
  12 #include <linux/bitops.h>
  13 #include <linux/device.h>
  14 #include <linux/err.h>
  15 #include <linux/io.h>
  16 #include <linux/irqreturn.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/kernel.h>
  19 #include <linux/module.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/of_device.h>
  22 #include <linux/thermal.h>
  23
  24 #define AVS_TMON_STATUS                 0x00
  25  #define AVS_TMON_STATUS_valid_msk      BIT(11)
  26  #define AVS_TMON_STATUS_data_msk       GENMASK(10, 1)
  27  #define AVS_TMON_STATUS_data_shift     1
  28
  29 #define AVS_TMON_EN_OVERTEMP_RESET      0x04
  30  #define AVS_TMON_EN_OVERTEMP_RESET_msk BIT(0)
  31
  32 #define AVS_TMON_RESET_THRESH           0x08
  33  #define AVS_TMON_RESET_THRESH_msk      GENMASK(10, 1)
  34  #define AVS_TMON_RESET_THRESH_shift    1
  35
  36 #define AVS_TMON_INT_IDLE_TIME          0x10
  37
  38 #define AVS_TMON_EN_TEMP_INT_SRCS       0x14
  39  #define AVS_TMON_EN_TEMP_INT_SRCS_high BIT(1)
  40  #define AVS_TMON_EN_TEMP_INT_SRCS_low  BIT(0)
  41
  42 #define AVS_TMON_INT_THRESH             0x18
  43  #define AVS_TMON_INT_THRESH_high_msk   GENMASK(26, 17)
  44  #define AVS_TMON_INT_THRESH_high_shift 17
  45  #define AVS_TMON_INT_THRESH_low_msk    GENMASK(10, 1)
  46  #define AVS_TMON_INT_THRESH_low_shift  1
  47
  48 #define AVS_TMON_TEMP_INT_CODE          0x1c
  49 #define AVS_TMON_TP_TEST_ENABLE         0x20
  50
  51 /* Default coefficients */
  52 #define AVS_TMON_TEMP_SLOPE             487
  53 #define AVS_TMON_TEMP_OFFSET            410040
  54
  55 /* HW related temperature constants */
  56 #define AVS_TMON_TEMP_MAX               0x3ff
  57 #define AVS_TMON_TEMP_MIN               -88161
  58 #define AVS_TMON_TEMP_MASK              AVS_TMON_TEMP_MAX
  59
  60 enum avs_tmon_trip_type {
  61         TMON_TRIP_TYPE_LOW = 0,
  62         TMON_TRIP_TYPE_HIGH,
  63         TMON_TRIP_TYPE_RESET,
  64         TMON_TRIP_TYPE_MAX,
  65 };
  66
  67 struct avs_tmon_trip {
  68         /* HW bit to enable the trip */
  69         u32 enable_offs;
  70         u32 enable_mask;
  71
  72         /* HW field to read the trip temperature */
  73         u32 reg_offs;
  74         u32 reg_msk;
  75         int reg_shift;
  76 };
  77
  78 static struct avs_tmon_trip avs_tmon_trips[] = {
  79         /* Trips when temperature is below threshold */
  80         [TMON_TRIP_TYPE_LOW] = {
  81                 .enable_offs    = AVS_TMON_EN_TEMP_INT_SRCS,
  82                 .enable_mask    = AVS_TMON_EN_TEMP_INT_SRCS_low,
  83                 .reg_offs       = AVS_TMON_INT_THRESH,
  84                 .reg_msk        = AVS_TMON_INT_THRESH_low_msk,
  85                 .reg_shift      = AVS_TMON_INT_THRESH_low_shift,
  86         },
  87         /* Trips when temperature is above threshold */
  88         [TMON_TRIP_TYPE_HIGH] = {
  89                 .enable_offs    = AVS_TMON_EN_TEMP_INT_SRCS,
  90                 .enable_mask    = AVS_TMON_EN_TEMP_INT_SRCS_high,
  91                 .reg_offs       = AVS_TMON_INT_THRESH,
  92                 .reg_msk        = AVS_TMON_INT_THRESH_high_msk,
  93                 .reg_shift      = AVS_TMON_INT_THRESH_high_shift,
  94         },
  95         /* Automatically resets chip when above threshold */
  96         [TMON_TRIP_TYPE_RESET] = {
  97                 .enable_offs    = AVS_TMON_EN_OVERTEMP_RESET,
  98                 .enable_mask    = AVS_TMON_EN_OVERTEMP_RESET_msk,
  99                 .reg_offs       = AVS_TMON_RESET_THRESH,
 100                 .reg_msk        = AVS_TMON_RESET_THRESH_msk,
 101                 .reg_shift      = AVS_TMON_RESET_THRESH_shift,
 102         },
 103 };
 104
 105 struct brcmstb_thermal_params {
 106         unsigned int offset;
 107         unsigned int mult;
 108         const struct thermal_zone_of_device_ops *of_ops;
 109 };
 110
 111 struct brcmstb_thermal_priv {
 112         void __iomem *tmon_base;
 113         struct device *dev;
 114         struct thermal_zone_device *thermal;
 115         /* Process specific thermal parameters used for calculations */
 116         const struct brcmstb_thermal_params *temp_params;
 117 };
 118
 119 /* Convert a HW code to a temperature reading (millidegree celsius) */
 120 static inline int avs_tmon_code_to_temp(struct brcmstb_thermal_priv *priv,
 121                                         u32 code)
 122 {
 123         int offset = priv->temp_params->offset;
 124         int mult = priv->temp_params->mult;
 125
 126         return (offset - (int)((code & AVS_TMON_TEMP_MASK) * mult));
 127 }
 128
 129 /*
 130  * Convert a temperature value (millidegree celsius) to a HW code
 131  *
 132  * @temp: temperature to convert
 133  * @low: if true, round toward the low side
 134  */
 135 static inline u32 avs_tmon_temp_to_code(struct brcmstb_thermal_priv *priv,
 136                                         int temp, bool low)
 137 {
 138         int offset = priv->temp_params->offset;
 139         int mult = priv->temp_params->mult;
 140
 141         if (temp < AVS_TMON_TEMP_MIN)
 142                 return AVS_TMON_TEMP_MAX;       /* Maximum code value */
 143
 144         if (temp >= offset)
 145                 return 0;       /* Minimum code value */
 146
 147         if (low)
 148                 return (u32)(DIV_ROUND_UP(offset - temp, mult));
 149         else
 150                 return (u32)((offset - temp) / mult);
 151 }
 152
 153 static int brcmstb_get_temp(void *data, int *temp)
 154 {
 155         struct brcmstb_thermal_priv *priv = data;
 156         u32 val;
 157         long t;
 158
 159         val = __raw_readl(priv->tmon_base + AVS_TMON_STATUS);
 160
 161         if (!(val & AVS_TMON_STATUS_valid_msk)) {
 162                 dev_err(priv->dev, "reading not valid\n");
 163                 return -EIO;
 164         }
 165
 166         val = (val & AVS_TMON_STATUS_data_msk) >> AVS_TMON_STATUS_data_shift;
 167
 168         t = avs_tmon_code_to_temp(priv, val);
 169         if (t < 0)
 170                 *temp = 0;
 171         else
 172                 *temp = t;
 173
 174         return 0;
 175 }
 176
 177 static void avs_tmon_trip_enable(struct brcmstb_thermal_priv *priv,
 178                                  enum avs_tmon_trip_type type, int en)
 179 {
 180         struct avs_tmon_trip *trip = &avs_tmon_trips[type];
 181         u32 val = __raw_readl(priv->tmon_base + trip->enable_offs);
 182
 183         dev_dbg(priv->dev, "%sable trip, type %d\n", en ? "en" : "dis", type);
 184
 185         if (en)
 186                 val |= trip->enable_mask;
 187         else
 188                 val &= ~trip->enable_mask;
 189
 190         __raw_writel(val, priv->tmon_base + trip->enable_offs);
 191 }
 192
 193 static int avs_tmon_get_trip_temp(struct brcmstb_thermal_priv *priv,
 194                                   enum avs_tmon_trip_type type)
 195 {
 196         struct avs_tmon_trip *trip = &avs_tmon_trips[type];
 197         u32 val = __raw_readl(priv->tmon_base + trip->reg_offs);
 198
 199         val &= trip->reg_msk;
 200         val >>= trip->reg_shift;
 201
 202         return avs_tmon_code_to_temp(priv, val);
 203 }
 204
 205 static void avs_tmon_set_trip_temp(struct brcmstb_thermal_priv *priv,
 206                                    enum avs_tmon_trip_type type,
 207                                    int temp)
 208 {
 209         struct avs_tmon_trip *trip = &avs_tmon_trips[type];
 210         u32 val, orig;
 211
 212         dev_dbg(priv->dev, "set temp %d to %d\n", type, temp);
 213
 214         /* round toward low temp for the low interrupt */
 215         val = avs_tmon_temp_to_code(priv, temp,
 216                                     type == TMON_TRIP_TYPE_LOW);
 217
 218         val <<= trip->reg_shift;
 219         val &= trip->reg_msk;
 220
 221         orig = __raw_readl(priv->tmon_base + trip->reg_offs);
 222         orig &= ~trip->reg_msk;
 223         orig |= val;
 224         __raw_writel(orig, priv->tmon_base + trip->reg_offs);
 225 }
 226
 227 static int avs_tmon_get_intr_temp(struct brcmstb_thermal_priv *priv)
 228 {
 229         u32 val;
 230
 231         val = __raw_readl(priv->tmon_base + AVS_TMON_TEMP_INT_CODE);
 232         return avs_tmon_code_to_temp(priv, val);
 233 }
 234
 235 static irqreturn_t brcmstb_tmon_irq_thread(int irq, void *data)
 236 {
 237         struct brcmstb_thermal_priv *priv = data;
 238         int low, high, intr;
 239
 240         low = avs_tmon_get_trip_temp(priv, TMON_TRIP_TYPE_LOW);
 241         high = avs_tmon_get_trip_temp(priv, TMON_TRIP_TYPE_HIGH);
 242         intr = avs_tmon_get_intr_temp(priv);
 243
 244         dev_dbg(priv->dev, "low/intr/high: %d/%d/%d\n",
 245                         low, intr, high);
 246
 247         /* Disable high-temp until next threshold shift */
 248         if (intr >= high)
 249                 avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_HIGH, 0);
 250         /* Disable low-temp until next threshold shift */
 251         if (intr <= low)
 252                 avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_LOW, 0);
 253
 254         /*
 255          * Notify using the interrupt temperature, in case the temperature
 256          * changes before it can next be read out
 257          */
 258         thermal_zone_device_update(priv->thermal, intr);
 259
 260         return IRQ_HANDLED;
 261 }
 262
 263 static int brcmstb_set_trips(void *data, int low, int high)
 264 {
 265         struct brcmstb_thermal_priv *priv = data;
 266
 267         dev_dbg(priv->dev, "set trips %d <--> %d\n", low, high);
 268
 269         /*
 270          * Disable low-temp if "low" is too small. As per thermal framework
 271          * API, we use -INT_MAX rather than INT_MIN.
 272          */
 273         if (low <= -INT_MAX) {
 274                 avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_LOW, 0);
 275         } else {
 276                 avs_tmon_set_trip_temp(priv, TMON_TRIP_TYPE_LOW, low);
 277                 avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_LOW, 1);
 278         }
 279
 280         /* Disable high-temp if "high" is too big. */
 281         if (high == INT_MAX) {
 282                 avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_HIGH, 0);
 283         } else {
 284                 avs_tmon_set_trip_temp(priv, TMON_TRIP_TYPE_HIGH, high);
 285                 avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_HIGH, 1);
 286         }
 287
 288         return 0;
 289 }
 290
 291 static const struct thermal_zone_of_device_ops brcmstb_16nm_of_ops = {
 292         .get_temp       = brcmstb_get_temp,
 293 };
 294
 295 static const struct brcmstb_thermal_params brcmstb_16nm_params = {
 296         .offset = 457829,
 297         .mult   = 557,
 298         .of_ops = &brcmstb_16nm_of_ops,
 299 };
 300
 301 static const struct thermal_zone_of_device_ops brcmstb_28nm_of_ops = {
 302         .get_temp       = brcmstb_get_temp,
 303         .set_trips      = brcmstb_set_trips,
 304 };
 305
 306 static const struct brcmstb_thermal_params brcmstb_28nm_params = {
 307         .offset = 410040,
 308         .mult   = 487,
 309         .of_ops = &brcmstb_28nm_of_ops,
 310 };
 311
 312 static const struct of_device_id brcmstb_thermal_id_table[] = {
 313         { .compatible = "brcm,avs-tmon-bcm7216", .data = &brcmstb_16nm_params },
 314         { .compatible = "brcm,avs-tmon", .data = &brcmstb_28nm_params },
 315         {},
 316 };
 317 MODULE_DEVICE_TABLE(of, brcmstb_thermal_id_table);
 318
 319 static int brcmstb_thermal_probe(struct platform_device *pdev)
 320 {
 321         const struct thermal_zone_of_device_ops *of_ops;
 322         struct thermal_zone_device *thermal;
 323         struct brcmstb_thermal_priv *priv;
 324         struct resource *res;
 325         int irq, ret;
 326
 327         priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
 328         if (!priv)
 329                 return -ENOMEM;
 330
 331         priv->temp_params = of_device_get_match_data(&pdev->dev);
 332         if (!priv->temp_params)
 333                 return -EINVAL;
 334
 335         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 336         priv->tmon_base = devm_ioremap_resource(&pdev->dev, res);
 337         if (IS_ERR(priv->tmon_base))
 338                 return PTR_ERR(priv->tmon_base);
 339
 340         priv->dev = &pdev->dev;
 341         platform_set_drvdata(pdev, priv);
 342         of_ops = priv->temp_params->of_ops;
 343
 344         thermal = devm_thermal_zone_of_sensor_register(&pdev->dev, 0, priv,
 345                                                        of_ops);
 346         if (IS_ERR(thermal)) {
 347                 ret = PTR_ERR(thermal);
 348                 dev_err(&pdev->dev, "could not register sensor: %d\n", ret);
 349                 return ret;
 350         }
 351
 352         priv->thermal = thermal;
 353
 354         irq = platform_get_irq(pdev, 0);
 355         if (irq >= 0) {
 356                 ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
 357                                                 brcmstb_tmon_irq_thread,
 358                                                 IRQF_ONESHOT,
 359                                                 DRV_NAME, priv);
 360                 if (ret < 0) {
 361                         dev_err(&pdev->dev, "could not request IRQ: %d\n", ret);
 362                         return ret;
 363                 }
 364         }
 365
 366         dev_info(&pdev->dev, "registered AVS TMON of-sensor driver\n");
 367
 368         return 0;
 369 }
 370
 371 static struct platform_driver brcmstb_thermal_driver = {
 372         .probe = brcmstb_thermal_probe,
 373         .driver = {
 374                 .name = DRV_NAME,
 375                 .of_match_table = brcmstb_thermal_id_table,
 376         },
 377 };
 378 module_platform_driver(brcmstb_thermal_driver);
 379
 380 MODULE_LICENSE("GPL v2");
 381 MODULE_AUTHOR("Brian Norris");
 382 MODULE_DESCRIPTION("Broadcom STB AVS TMON thermal driver");