drivers/thermal/imx_thermal.c

   1 /*
   2  * (C) Copyright 2014 Freescale Semiconductor, Inc.
   3  * Author: Nitin Garg <nitin.garg@freescale.com>
   4  *             Ye Li <Ye.Li@freescale.com>
   5  *
   6  * SPDX-License-Identifier:     GPL-2.0+
   7  */
   8
   9 #include <config.h>
  10 #include <common.h>
  11 #include <div64.h>
  12 #include <fuse.h>
  13 #include <asm/io.h>
  14 #include <asm/arch/clock.h>
  15 #include <asm/arch/sys_proto.h>
  16 #include <dm.h>
  17 #include <errno.h>
  18 #include <malloc.h>
  19 #include <thermal.h>
  20 #include <imx_thermal.h>
  21
  22 /* board will busyloop until this many degrees C below CPU max temperature */
  23 #define TEMPERATURE_HOT_DELTA   5 /* CPU maxT - 5C */
  24 #define FACTOR0                 10000000
  25 #define FACTOR1                 15976
  26 #define FACTOR2                 4297157
  27 #define MEASURE_FREQ            327
  28 #define TEMPERATURE_MIN         -40
  29 #define TEMPERATURE_HOT         85
  30 #define TEMPERATURE_MAX         125
  31
  32 #define TEMPSENSE0_TEMP_CNT_SHIFT       8
  33 #define TEMPSENSE0_TEMP_CNT_MASK        (0xfff << TEMPSENSE0_TEMP_CNT_SHIFT)
  34 #define TEMPSENSE0_FINISHED             (1 << 2)
  35 #define TEMPSENSE0_MEASURE_TEMP         (1 << 1)
  36 #define TEMPSENSE0_POWER_DOWN           (1 << 0)
  37 #define MISC0_REFTOP_SELBIASOFF         (1 << 3)
  38 #define TEMPSENSE1_MEASURE_FREQ         0xffff
  39
  40 struct thermal_data {
  41         unsigned int fuse;
  42         int critical;
  43         int minc;
  44         int maxc;
  45 };
  46
  47 #if defined(CONFIG_MX6)
  48 static int read_cpu_temperature(struct udevice *dev)
  49 {
  50         int temperature;
  51         unsigned int reg, n_meas;
  52         const struct imx_thermal_plat *pdata = dev_get_platdata(dev);
  53         struct anatop_regs *anatop = (struct anatop_regs *)pdata->regs;
  54         struct thermal_data *priv = dev_get_priv(dev);
  55         u32 fuse = priv->fuse;
  56         int t1, n1;
  57         u32 c1, c2;
  58         u64 temp64;
  59
  60         /*
  61          * Sensor data layout:
  62          *   [31:20] - sensor value @ 25C
  63          * We use universal formula now and only need sensor value @ 25C
  64          * slope = 0.4297157 - (0.0015976 * 25C fuse)
  65          */
  66         n1 = fuse >> 20;
  67         t1 = 25; /* t1 always 25C */
  68
  69         /*
  70          * Derived from linear interpolation:
  71          * slope = 0.4297157 - (0.0015976 * 25C fuse)
  72          * slope = (FACTOR2 - FACTOR1 * n1) / FACTOR0
  73          * (Nmeas - n1) / (Tmeas - t1) = slope
  74          * We want to reduce this down to the minimum computation necessary
  75          * for each temperature read.  Also, we want Tmeas in millicelsius
  76          * and we don't want to lose precision from integer division. So...
  77          * Tmeas = (Nmeas - n1) / slope + t1
  78          * milli_Tmeas = 1000 * (Nmeas - n1) / slope + 1000 * t1
  79          * milli_Tmeas = -1000 * (n1 - Nmeas) / slope + 1000 * t1
  80          * Let constant c1 = (-1000 / slope)
  81          * milli_Tmeas = (n1 - Nmeas) * c1 + 1000 * t1
  82          * Let constant c2 = n1 *c1 + 1000 * t1
  83          * milli_Tmeas = c2 - Nmeas * c1
  84          */
  85         temp64 = FACTOR0;
  86         temp64 *= 1000;
  87         do_div(temp64, FACTOR1 * n1 - FACTOR2);
  88         c1 = temp64;
  89         c2 = n1 * c1 + 1000 * t1;
  90
  91         /*
  92          * now we only use single measure, every time we read
  93          * the temperature, we will power on/down anadig thermal
  94          * module
  95          */
  96         writel(TEMPSENSE0_POWER_DOWN, &anatop->tempsense0_clr);
  97         writel(MISC0_REFTOP_SELBIASOFF, &anatop->ana_misc0_set);
  98
  99         /* setup measure freq */
 100         reg = readl(&anatop->tempsense1);
 101         reg &= ~TEMPSENSE1_MEASURE_FREQ;
 102         reg |= MEASURE_FREQ;
 103         writel(reg, &anatop->tempsense1);
 104
 105         /* start the measurement process */
 106         writel(TEMPSENSE0_MEASURE_TEMP, &anatop->tempsense0_clr);
 107         writel(TEMPSENSE0_FINISHED, &anatop->tempsense0_clr);
 108         writel(TEMPSENSE0_MEASURE_TEMP, &anatop->tempsense0_set);
 109
 110         /* make sure that the latest temp is valid */
 111         while ((readl(&anatop->tempsense0) &
 112                 TEMPSENSE0_FINISHED) == 0)
 113                 udelay(10000);
 114
 115         /* read temperature count */
 116         reg = readl(&anatop->tempsense0);
 117         n_meas = (reg & TEMPSENSE0_TEMP_CNT_MASK)
 118                 >> TEMPSENSE0_TEMP_CNT_SHIFT;
 119         writel(TEMPSENSE0_FINISHED, &anatop->tempsense0_clr);
 120
 121         /* milli_Tmeas = c2 - Nmeas * c1 */
 122         temperature = (long)(c2 - n_meas * c1)/1000;
 123
 124         /* power down anatop thermal sensor */
 125         writel(TEMPSENSE0_POWER_DOWN, &anatop->tempsense0_set);
 126         writel(MISC0_REFTOP_SELBIASOFF, &anatop->ana_misc0_clr);
 127
 128         return temperature;
 129 }
 130 #elif defined(CONFIG_MX7)
 131 static int read_cpu_temperature(struct udevice *dev)
 132 {
 133         unsigned int reg, tmp, start;
 134         unsigned int raw_25c, te1;
 135         int temperature;
 136         unsigned int *priv = dev_get_priv(dev);
 137         u32 fuse = *priv;
 138         struct mxc_ccm_anatop_reg *ccm_anatop = (struct mxc_ccm_anatop_reg *)
 139                                                  ANATOP_BASE_ADDR;
 140         /*
 141          * fuse data layout:
 142          * [31:21] sensor value @ 25C
 143          * [20:18] hot temperature value
 144          * [17:9] sensor value of room
 145          * [8:0] sensor value of hot
 146          */
 147
 148         raw_25c = fuse >> 21;
 149         if (raw_25c == 0)
 150                 raw_25c = 25;
 151
 152         te1 = (fuse >> 9) & 0x1ff;
 153
 154         /*
 155          * now we only use single measure, every time we read
 156          * the temperature, we will power on/down anadig thermal
 157          * module
 158          */
 159         writel(TEMPMON_HW_ANADIG_TEMPSENSE1_POWER_DOWN_MASK, &ccm_anatop->tempsense1_clr);
 160         writel(PMU_REF_REFTOP_SELFBIASOFF_MASK, &ccm_anatop->ref_set);
 161
 162         /* write measure freq */
 163         reg = readl(&ccm_anatop->tempsense1);
 164         reg &= ~TEMPMON_HW_ANADIG_TEMPSENSE1_MEASURE_FREQ_MASK;
 165         reg |= TEMPMON_HW_ANADIG_TEMPSENSE1_MEASURE_FREQ(MEASURE_FREQ);
 166         writel(reg, &ccm_anatop->tempsense1);
 167
 168         writel(TEMPMON_HW_ANADIG_TEMPSENSE1_MEASURE_TEMP_MASK, &ccm_anatop->tempsense1_clr);
 169         writel(TEMPMON_HW_ANADIG_TEMPSENSE1_FINISHED_MASK, &ccm_anatop->tempsense1_clr);
 170         writel(TEMPMON_HW_ANADIG_TEMPSENSE1_MEASURE_TEMP_MASK, &ccm_anatop->tempsense1_set);
 171
 172         start = get_timer(0);
 173         /* Wait max 100ms */
 174         do {
 175                 /*
 176                  * Since we can not rely on finish bit, use 1ms delay to get
 177                  * temperature. From RM, 17us is enough to get data, but
 178                  * to gurantee to get the data, delay 100ms here.
 179                  */
 180                 reg = readl(&ccm_anatop->tempsense1);
 181                 tmp = (reg & TEMPMON_HW_ANADIG_TEMPSENSE1_TEMP_VALUE_MASK)
 182                        >> TEMPMON_HW_ANADIG_TEMPSENSE1_TEMP_VALUE_SHIFT;
 183         } while (get_timer(0) < (start + 100));
 184
 185         writel(TEMPMON_HW_ANADIG_TEMPSENSE1_FINISHED_MASK, &ccm_anatop->tempsense1_clr);
 186
 187         /* power down anatop thermal sensor */
 188         writel(TEMPMON_HW_ANADIG_TEMPSENSE1_POWER_DOWN_MASK, &ccm_anatop->tempsense1_set);
 189         writel(PMU_REF_REFTOP_SELFBIASOFF_MASK, &ccm_anatop->ref_clr);
 190
 191         /* Single point */
 192         temperature = tmp - (te1 - raw_25c);
 193
 194         return temperature;
 195 }
 196 #endif
 197
 198 int imx_thermal_get_temp(struct udevice *dev, int *temp)
 199 {
 200         struct thermal_data *priv = dev_get_priv(dev);
 201         int cpu_tmp = 0;
 202
 203         cpu_tmp = read_cpu_temperature(dev);
 204
 205         while (cpu_tmp >= priv->critical) {
 206                 printf("CPU Temperature (%dC) too close to max (%dC)",
 207                        cpu_tmp, priv->maxc);
 208                 puts(" waiting...\n");
 209                 udelay(5000000);
 210                 cpu_tmp = read_cpu_temperature(dev);
 211         }
 212
 213         *temp = cpu_tmp;
 214
 215         return 0;
 216 }
 217
 218 static const struct dm_thermal_ops imx_thermal_ops = {
 219         .get_temp       = imx_thermal_get_temp,
 220 };
 221
 222 static int imx_thermal_probe(struct udevice *dev)
 223 {
 224         unsigned int fuse = ~0;
 225
 226         const struct imx_thermal_plat *pdata = dev_get_platdata(dev);
 227         struct thermal_data *priv = dev_get_priv(dev);
 228
 229         /* Read Temperature calibration data fuse */
 230         fuse_read(pdata->fuse_bank, pdata->fuse_word, &fuse);
 231
 232         if (is_soc_type(MXC_SOC_MX6)) {
 233                 /* Check for valid fuse */
 234                 if (fuse == 0 || fuse == ~0) {
 235                         printf("CPU:   Thermal invalid data, fuse: 0x%x\n",
 236                                 fuse);
 237                         return -EPERM;
 238                 }
 239         } else if (is_soc_type(MXC_SOC_MX7)) {
 240                 /* No Calibration data in FUSE? */
 241                 if ((fuse & 0x3ffff) == 0)
 242                         return -EPERM;
 243                 /* We do not support 105C TE2 */
 244                 if (((fuse & 0x1c0000) >> 18) == 0x6)
 245                         return -EPERM;
 246         }
 247
 248         /* set critical cooling temp */
 249         get_cpu_temp_grade(&priv->minc, &priv->maxc);
 250         priv->critical = priv->maxc - TEMPERATURE_HOT_DELTA;
 251         priv->fuse = fuse;
 252
 253         enable_thermal_clk();
 254
 255         return 0;
 256 }
 257
 258 U_BOOT_DRIVER(imx_thermal) = {
 259         .name   = "imx_thermal",
 260         .id     = UCLASS_THERMAL,
 261         .ops    = &imx_thermal_ops,
 262         .probe  = imx_thermal_probe,
 263         .priv_auto_alloc_size = sizeof(struct thermal_data),
 264         .flags  = DM_FLAG_PRE_RELOC,
 265 };