drivers/thermal/armada_thermal.c

   1 /*
   2  * Marvell Armada 370/XP thermal sensor driver
   3  *
   4  * Copyright (C) 2013 Marvell
   5  *
   6  * This software is licensed under the terms of the GNU General Public
   7  * License version 2, as published by the Free Software Foundation, and
   8  * may be copied, distributed, and modified under those terms.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  */
  16 #include <linux/device.h>
  17 #include <linux/err.h>
  18 #include <linux/io.h>
  19 #include <linux/kernel.h>
  20 #include <linux/of.h>
  21 #include <linux/module.h>
  22 #include <linux/delay.h>
  23 #include <linux/platform_device.h>
  24 #include <linux/of_device.h>
  25 #include <linux/thermal.h>
  26
  27 #define THERMAL_VALID_MASK              0x1
  28
  29 /* Thermal Manager Control and Status Register */
  30 #define PMU_TDC0_SW_RST_MASK            (0x1 << 1)
  31 #define PMU_TM_DISABLE_OFFS             0
  32 #define PMU_TM_DISABLE_MASK             (0x1 << PMU_TM_DISABLE_OFFS)
  33 #define PMU_TDC0_REF_CAL_CNT_OFFS       11
  34 #define PMU_TDC0_REF_CAL_CNT_MASK       (0x1ff << PMU_TDC0_REF_CAL_CNT_OFFS)
  35 #define PMU_TDC0_OTF_CAL_MASK           (0x1 << 30)
  36 #define PMU_TDC0_START_CAL_MASK         (0x1 << 25)
  37
  38 #define A375_UNIT_CONTROL_SHIFT         27
  39 #define A375_UNIT_CONTROL_MASK          0x7
  40 #define A375_READOUT_INVERT             BIT(15)
  41 #define A375_HW_RESETn                  BIT(8)
  42 #define A380_HW_RESET                   BIT(8)
  43
  44 struct armada_thermal_data;
  45
  46 /* Marvell EBU Thermal Sensor Dev Structure */
  47 struct armada_thermal_priv {
  48         void __iomem *sensor;
  49         void __iomem *control;
  50         struct armada_thermal_data *data;
  51 };
  52
  53 struct armada_thermal_data {
  54         /* Initialize the sensor */
  55         void (*init_sensor)(struct platform_device *pdev,
  56                             struct armada_thermal_priv *);
  57
  58         /* Test for a valid sensor value (optional) */
  59         bool (*is_valid)(struct armada_thermal_priv *);
  60
  61         /* Formula coeficients: temp = (b + m * reg) / div */
  62         unsigned long coef_b;
  63         unsigned long coef_m;
  64         unsigned long coef_div;
  65         bool inverted;
  66
  67         /* Register shift and mask to access the sensor temperature */
  68         unsigned int temp_shift;
  69         unsigned int temp_mask;
  70         unsigned int is_valid_shift;
  71 };
  72
  73 static void armadaxp_init_sensor(struct platform_device *pdev,
  74                                  struct armada_thermal_priv *priv)
  75 {
  76         unsigned long reg;
  77
  78         reg = readl_relaxed(priv->control);
  79         reg |= PMU_TDC0_OTF_CAL_MASK;
  80         writel(reg, priv->control);
  81
  82         /* Reference calibration value */
  83         reg &= ~PMU_TDC0_REF_CAL_CNT_MASK;
  84         reg |= (0xf1 << PMU_TDC0_REF_CAL_CNT_OFFS);
  85         writel(reg, priv->control);
  86
  87         /* Reset the sensor */
  88         reg = readl_relaxed(priv->control);
  89         writel((reg | PMU_TDC0_SW_RST_MASK), priv->control);
  90
  91         writel(reg, priv->control);
  92
  93         /* Enable the sensor */
  94         reg = readl_relaxed(priv->sensor);
  95         reg &= ~PMU_TM_DISABLE_MASK;
  96         writel(reg, priv->sensor);
  97 }
  98
  99 static void armada370_init_sensor(struct platform_device *pdev,
 100                                   struct armada_thermal_priv *priv)
 101 {
 102         unsigned long reg;
 103
 104         reg = readl_relaxed(priv->control);
 105         reg |= PMU_TDC0_OTF_CAL_MASK;
 106         writel(reg, priv->control);
 107
 108         /* Reference calibration value */
 109         reg &= ~PMU_TDC0_REF_CAL_CNT_MASK;
 110         reg |= (0xf1 << PMU_TDC0_REF_CAL_CNT_OFFS);
 111         writel(reg, priv->control);
 112
 113         reg &= ~PMU_TDC0_START_CAL_MASK;
 114         writel(reg, priv->control);
 115
 116         mdelay(10);
 117 }
 118
 119 static void armada375_init_sensor(struct platform_device *pdev,
 120                                   struct armada_thermal_priv *priv)
 121 {
 122         unsigned long reg;
 123
 124         reg = readl(priv->control + 4);
 125         reg &= ~(A375_UNIT_CONTROL_MASK << A375_UNIT_CONTROL_SHIFT);
 126         reg &= ~A375_READOUT_INVERT;
 127         reg &= ~A375_HW_RESETn;
 128
 129         writel(reg, priv->control + 4);
 130         mdelay(20);
 131
 132         reg |= A375_HW_RESETn;
 133         writel(reg, priv->control + 4);
 134         mdelay(50);
 135 }
 136
 137 static void armada380_init_sensor(struct platform_device *pdev,
 138                                   struct armada_thermal_priv *priv)
 139 {
 140         unsigned long reg = readl_relaxed(priv->control);
 141
 142         /* Reset hardware once */
 143         if (!(reg & A380_HW_RESET)) {
 144                 reg |= A380_HW_RESET;
 145                 writel(reg, priv->control);
 146                 mdelay(10);
 147         }
 148 }
 149
 150 static bool armada_is_valid(struct armada_thermal_priv *priv)
 151 {
 152         unsigned long reg = readl_relaxed(priv->sensor);
 153
 154         return (reg >> priv->data->is_valid_shift) & THERMAL_VALID_MASK;
 155 }
 156
 157 static int armada_get_temp(struct thermal_zone_device *thermal,
 158                           int *temp)
 159 {
 160         struct armada_thermal_priv *priv = thermal->devdata;
 161         unsigned long reg;
 162         unsigned long m, b, div;
 163
 164         /* Valid check */
 165         if (priv->data->is_valid && !priv->data->is_valid(priv)) {
 166                 dev_err(&thermal->device,
 167                         "Temperature sensor reading not valid\n");
 168                 return -EIO;
 169         }
 170
 171         reg = readl_relaxed(priv->sensor);
 172         reg = (reg >> priv->data->temp_shift) & priv->data->temp_mask;
 173
 174         /* Get formula coeficients */
 175         b = priv->data->coef_b;
 176         m = priv->data->coef_m;
 177         div = priv->data->coef_div;
 178
 179         if (priv->data->inverted)
 180                 *temp = ((m * reg) - b) / div;
 181         else
 182                 *temp = (b - (m * reg)) / div;
 183         return 0;
 184 }
 185
 186 static struct thermal_zone_device_ops ops = {
 187         .get_temp = armada_get_temp,
 188 };
 189
 190 static const struct armada_thermal_data armadaxp_data = {
 191         .init_sensor = armadaxp_init_sensor,
 192         .temp_shift = 10,
 193         .temp_mask = 0x1ff,
 194         .coef_b = 3153000000UL,
 195         .coef_m = 10000000UL,
 196         .coef_div = 13825,
 197 };
 198
 199 static const struct armada_thermal_data armada370_data = {
 200         .is_valid = armada_is_valid,
 201         .init_sensor = armada370_init_sensor,
 202         .is_valid_shift = 9,
 203         .temp_shift = 10,
 204         .temp_mask = 0x1ff,
 205         .coef_b = 3153000000UL,
 206         .coef_m = 10000000UL,
 207         .coef_div = 13825,
 208 };
 209
 210 static const struct armada_thermal_data armada375_data = {
 211         .is_valid = armada_is_valid,
 212         .init_sensor = armada375_init_sensor,
 213         .is_valid_shift = 10,
 214         .temp_shift = 0,
 215         .temp_mask = 0x1ff,
 216         .coef_b = 3171900000UL,
 217         .coef_m = 10000000UL,
 218         .coef_div = 13616,
 219 };
 220
 221 static const struct armada_thermal_data armada380_data = {
 222         .is_valid = armada_is_valid,
 223         .init_sensor = armada380_init_sensor,
 224         .is_valid_shift = 10,
 225         .temp_shift = 0,
 226         .temp_mask = 0x3ff,
 227         .coef_b = 2931108200UL,
 228         .coef_m = 5000000UL,
 229         .coef_div = 10502,
 230         .inverted = true,
 231 };
 232
 233 static const struct of_device_id armada_thermal_id_table[] = {
 234         {
 235                 .compatible = "marvell,armadaxp-thermal",
 236                 .data       = &armadaxp_data,
 237         },
 238         {
 239                 .compatible = "marvell,armada370-thermal",
 240                 .data       = &armada370_data,
 241         },
 242         {
 243                 .compatible = "marvell,armada375-thermal",
 244                 .data       = &armada375_data,
 245         },
 246         {
 247                 .compatible = "marvell,armada380-thermal",
 248                 .data       = &armada380_data,
 249         },
 250         {
 251                 /* sentinel */
 252         },
 253 };
 254 MODULE_DEVICE_TABLE(of, armada_thermal_id_table);
 255
 256 static int armada_thermal_probe(struct platform_device *pdev)
 257 {
 258         struct thermal_zone_device *thermal;
 259         const struct of_device_id *match;
 260         struct armada_thermal_priv *priv;
 261         struct resource *res;
 262
 263         match = of_match_device(armada_thermal_id_table, &pdev->dev);
 264         if (!match)
 265                 return -ENODEV;
 266
 267         priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
 268         if (!priv)
 269                 return -ENOMEM;
 270
 271         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 272         priv->sensor = devm_ioremap_resource(&pdev->dev, res);
 273         if (IS_ERR(priv->sensor))
 274                 return PTR_ERR(priv->sensor);
 275
 276         res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 277         priv->control = devm_ioremap_resource(&pdev->dev, res);
 278         if (IS_ERR(priv->control))
 279                 return PTR_ERR(priv->control);
 280
 281         priv->data = (struct armada_thermal_data *)match->data;
 282         priv->data->init_sensor(pdev, priv);
 283
 284         thermal = thermal_zone_device_register("armada_thermal", 0, 0,
 285                                                priv, &ops, NULL, 0, 0);
 286         if (IS_ERR(thermal)) {
 287                 dev_err(&pdev->dev,
 288                         "Failed to register thermal zone device\n");
 289                 return PTR_ERR(thermal);
 290         }
 291
 292         platform_set_drvdata(pdev, thermal);
 293
 294         return 0;
 295 }
 296
 297 static int armada_thermal_exit(struct platform_device *pdev)
 298 {
 299         struct thermal_zone_device *armada_thermal =
 300                 platform_get_drvdata(pdev);
 301
 302         thermal_zone_device_unregister(armada_thermal);
 303
 304         return 0;
 305 }
 306
 307 static struct platform_driver armada_thermal_driver = {
 308         .probe = armada_thermal_probe,
 309         .remove = armada_thermal_exit,
 310         .driver = {
 311                 .name = "armada_thermal",
 312                 .of_match_table = armada_thermal_id_table,
 313         },
 314 };
 315
 316 module_platform_driver(armada_thermal_driver);
 317
 318 MODULE_AUTHOR("Ezequiel Garcia <ezequiel.garcia@free-electrons.com>");
 319 MODULE_DESCRIPTION("Armada 370/XP thermal driver");
 320 MODULE_LICENSE("GPL v2");