drivers/power/exynos-tmu.c

   1 /*
   2  * Copyright (c) 2012 Samsung Electronics Co., Ltd.
   3  *      http://www.samsung.com
   4  * Akshay Saraswat <akshay.s@samsung.com>
   5  *
   6  * EXYNOS - Thermal Management Unit
   7  *
   8  * See file CREDITS for list of people who contributed to this
   9  * project.
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License version 2 as
  13  * published by the Free Software Foundation.
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  17  * MA 02111-1307 USA
  18  */
  19
  20 #include <common.h>
  21 #include <errno.h>
  22 #include <fdtdec.h>
  23 #include <tmu.h>
  24 #include <asm/arch/tmu.h>
  25
  26 #define TRIMINFO_RELOAD         1
  27 #define CORE_EN                 1
  28
  29 #define INTEN_RISE0             1
  30 #define INTEN_RISE1             (1 << 4)
  31 #define INTEN_RISE2             (1 << 8)
  32 #define INTEN_FALL0             (1 << 16)
  33 #define INTEN_FALL1             (1 << 20)
  34 #define INTEN_FALL2             (1 << 24)
  35
  36 #define TRIM_INFO_MASK          0xff
  37
  38 #define INTCLEAR_RISE0          1
  39 #define INTCLEAR_RISE1          (1 << 4)
  40 #define INTCLEAR_RISE2          (1 << 8)
  41 #define INTCLEAR_FALL0          (1 << 16)
  42 #define INTCLEAR_FALL1          (1 << 20)
  43 #define INTCLEAR_FALL2          (1 << 24)
  44 #define INTCLEARALL             (INTCLEAR_RISE0 | INTCLEAR_RISE1 | \
  45                                  INTCLEAR_RISE2 | INTCLEAR_FALL0 | \
  46                                  INTCLEAR_FALL1 | INTCLEAR_FALL2)
  47
  48 /* Tmeperature threshold values for various thermal events */
  49 struct temperature_params {
  50         /* minimum value in temperature code range */
  51         unsigned int min_val;
  52         /* maximum value in temperature code range */
  53         unsigned int max_val;
  54         /* temperature threshold to start warning */
  55         unsigned int start_warning;
  56         /* temperature threshold CPU tripping */
  57         unsigned int start_tripping;
  58 };
  59
  60 /* Pre-defined values and thresholds for calibration of current temperature */
  61 struct tmu_data {
  62         /* pre-defined temperature thresholds */
  63         struct temperature_params ts;
  64         /* pre-defined efuse range minimum value */
  65         unsigned int efuse_min_value;
  66         /* pre-defined efuse value for temperature calibration */
  67         unsigned int efuse_value;
  68         /* pre-defined efuse range maximum value */
  69         unsigned int efuse_max_value;
  70         /* current temperature sensing slope */
  71         unsigned int slope;
  72 };
  73
  74 /* TMU device specific details and status */
  75 struct tmu_info {
  76         /* base Address for the TMU */
  77         unsigned tmu_base;
  78         /* pre-defined values for calibration and thresholds */
  79         struct tmu_data data;
  80         /* value required for triminfo_25 calibration */
  81         unsigned int te1;
  82         /* value required for triminfo_85 calibration */
  83         unsigned int te2;
  84         /* Value for measured data calibration */
  85         int dc_value;
  86         /* enum value indicating status of the TMU */
  87         int tmu_state;
  88 };
  89
  90 /* Global struct tmu_info variable to store init values */
  91 static struct tmu_info gbl_info;
  92
  93 /*
  94  * Get current temperature code from register,
  95  * then calculate and calibrate it's value
  96  * in degree celsius.
  97  *
  98  * @return      current temperature of the chip as sensed by TMU
  99  */
 100 static int get_cur_temp(struct tmu_info *info)
 101 {
 102         int cur_temp;
 103         struct exynos5_tmu_reg *reg = (struct exynos5_tmu_reg *)info->tmu_base;
 104
 105         /*
 106          * Temperature code range between min 25 and max 125.
 107          * May run more than once for first call as initial sensing
 108          * has not yet happened.
 109          */
 110         do {
 111                 cur_temp = readl(&reg->current_temp) & 0xff;
 112         } while (cur_temp == 0 && info->tmu_state == TMU_STATUS_NORMAL);
 113
 114         /* Calibrate current temperature */
 115         cur_temp = cur_temp - info->te1 + info->dc_value;
 116
 117         return cur_temp;
 118 }
 119
 120 /*
 121  * Monitors status of the TMU device and exynos temperature
 122  *
 123  * @param temp  pointer to the current temperature value
 124  * @return      enum tmu_status_t value, code indicating event to execute
 125  */
 126 enum tmu_status_t tmu_monitor(int *temp)
 127 {
 128         int cur_temp;
 129         struct tmu_data *data = &gbl_info.data;
 130
 131         if (gbl_info.tmu_state == TMU_STATUS_INIT)
 132                 return TMU_STATUS_INIT;
 133
 134         /* Read current temperature of the SOC */
 135         cur_temp = get_cur_temp(&gbl_info);
 136         *temp = cur_temp;
 137
 138         /* Temperature code lies between min 25 and max 125 */
 139         if (cur_temp >= data->ts.start_tripping &&
 140                         cur_temp <= data->ts.max_val) {
 141                 return TMU_STATUS_TRIPPED;
 142         } else if (cur_temp >= data->ts.start_warning) {
 143                 return TMU_STATUS_WARNING;
 144         } else if (cur_temp < data->ts.start_warning &&
 145                         cur_temp >= data->ts.min_val) {
 146                 return TMU_STATUS_NORMAL;
 147         } else {
 148                 /* Temperature code does not lie between min 25 and max 125 */
 149                 gbl_info.tmu_state = TMU_STATUS_INIT;
 150                 debug("EXYNOS_TMU: Thermal reading failed\n");
 151                 return TMU_STATUS_INIT;
 152         }
 153 }
 154
 155 /*
 156  * Get TMU specific pre-defined values from FDT
 157  *
 158  * @param info  pointer to the tmu_info struct
 159  * @param blob  FDT blob
 160  * @return      int value, 0 for success
 161  */
 162 static int get_tmu_fdt_values(struct tmu_info *info, const void *blob)
 163 {
 164 #ifdef CONFIG_OF_CONTROL
 165         int node;
 166         int error = 0;
 167
 168         /* Get the node from FDT for TMU */
 169         node = fdtdec_next_compatible(blob, 0,
 170                                       COMPAT_SAMSUNG_EXYNOS_TMU);
 171         if (node < 0) {
 172                 debug("EXYNOS_TMU: No node for tmu in device tree\n");
 173                 return -1;
 174         }
 175
 176         /*
 177          * Get the pre-defined TMU specific values from FDT.
 178          * All of these are expected to be correct otherwise
 179          * miscalculation of register values in tmu_setup_parameters
 180          * may result in misleading current temperature.
 181          */
 182         info->tmu_base = fdtdec_get_addr(blob, node, "reg");
 183         if (info->tmu_base == FDT_ADDR_T_NONE) {
 184                 debug("%s: Missing tmu-base\n", __func__);
 185                 return -1;
 186         }
 187         info->data.ts.min_val = fdtdec_get_int(blob,
 188                                 node, "samsung,min-temp", -1);
 189         error |= info->data.ts.min_val;
 190         info->data.ts.max_val = fdtdec_get_int(blob,
 191                                 node, "samsung,max-temp", -1);
 192         error |= info->data.ts.max_val;
 193         info->data.ts.start_warning = fdtdec_get_int(blob,
 194                                 node, "samsung,start-warning", -1);
 195         error |= info->data.ts.start_warning;
 196         info->data.ts.start_tripping = fdtdec_get_int(blob,
 197                                 node, "samsung,start-tripping", -1);
 198         error |= info->data.ts.start_tripping;
 199         info->data.efuse_min_value = fdtdec_get_int(blob,
 200                                 node, "samsung,efuse-min-value", -1);
 201         error |= info->data.efuse_min_value;
 202         info->data.efuse_value = fdtdec_get_int(blob,
 203                                 node, "samsung,efuse-value", -1);
 204         error |= info->data.efuse_value;
 205         info->data.efuse_max_value = fdtdec_get_int(blob,
 206                                 node, "samsung,efuse-max-value", -1);
 207         error |= info->data.efuse_max_value;
 208         info->data.slope = fdtdec_get_int(blob,
 209                                 node, "samsung,slope", -1);
 210         error |= info->data.slope;
 211         info->dc_value = fdtdec_get_int(blob,
 212                                 node, "samsung,dc-value", -1);
 213         error |= info->dc_value;
 214
 215         if (error == -1) {
 216                 debug("fail to get tmu node properties\n");
 217                 return -1;
 218         }
 219 #endif
 220
 221         return 0;
 222 }
 223
 224 /*
 225  * Calibrate and calculate threshold values and
 226  * enable interrupt levels
 227  *
 228  * @param       info pointer to the tmu_info struct
 229  */
 230 static void tmu_setup_parameters(struct tmu_info *info)
 231 {
 232         unsigned int te_code, con;
 233         unsigned int warning_code, trip_code;
 234         unsigned int cooling_temp;
 235         unsigned int rising_value;
 236         struct tmu_data *data = &info->data;
 237         struct exynos5_tmu_reg *reg = (struct exynos5_tmu_reg *)info->tmu_base;
 238
 239         /* Must reload for reading efuse value from triminfo register */
 240         writel(TRIMINFO_RELOAD, &reg->triminfo_control);
 241
 242         /* Get the compensation parameter */
 243         te_code = readl(&reg->triminfo);
 244         info->te1 = te_code & TRIM_INFO_MASK;
 245         info->te2 = ((te_code >> 8) & TRIM_INFO_MASK);
 246
 247         if ((data->efuse_min_value > info->te1) ||
 248                         (info->te1 > data->efuse_max_value)
 249                         ||  (info->te2 != 0))
 250                 info->te1 = data->efuse_value;
 251
 252         /* Get RISING & FALLING Threshold value */
 253         warning_code = data->ts.start_warning
 254                         + info->te1 - info->dc_value;
 255         trip_code = data->ts.start_tripping
 256                         + info->te1 - info->dc_value;
 257         cooling_temp = 0;
 258
 259         rising_value = ((warning_code << 8) | (trip_code << 16));
 260
 261         /* Set interrupt level */
 262         writel(rising_value, &reg->threshold_temp_rise);
 263         writel(cooling_temp, &reg->threshold_temp_fall);
 264
 265         /*
 266          * Init TMU control tuning parameters
 267          * [28:24] VREF - Voltage reference
 268          * [15:13] THERM_TRIP_MODE - Tripping mode
 269          * [12] THERM_TRIP_EN - Thermal tripping enable
 270          * [11:8] BUF_SLOPE_SEL - Gain of amplifier
 271          * [6] THERM_TRIP_BY_TQ_EN - Tripping by TQ pin
 272          */
 273         writel(data->slope, &reg->tmu_control);
 274
 275         writel(INTCLEARALL, &reg->intclear);
 276
 277         /* TMU core enable */
 278         con = readl(&reg->tmu_control);
 279         con |= CORE_EN;
 280
 281         writel(con, &reg->tmu_control);
 282
 283         /* LEV0 LEV1 LEV2 interrupt enable */
 284         writel(INTEN_RISE0 | INTEN_RISE1 | INTEN_RISE2, &reg->inten);
 285 }
 286
 287 /*
 288  * Initialize TMU device
 289  *
 290  * @param blob  FDT blob
 291  * @return      int value, 0 for success
 292  */
 293 int tmu_init(const void *blob)
 294 {
 295         gbl_info.tmu_state = TMU_STATUS_INIT;
 296         if (get_tmu_fdt_values(&gbl_info, blob) < 0)
 297                 goto ret;
 298
 299         tmu_setup_parameters(&gbl_info);
 300         gbl_info.tmu_state = TMU_STATUS_NORMAL;
 301 ret:
 302
 303         return gbl_info.tmu_state;
 304 }