2 * (C) Copyright 2014 Freescale Semiconductor, Inc.
3 * Author: Nitin Garg <nitin.garg@freescale.com>
4 * Ye Li <Ye.Li@freescale.com>
6 * SPDX-License-Identifier: GPL-2.0+
14 #include <asm/arch/clock.h>
15 #include <asm/arch/sys_proto.h>
20 #include <imx_thermal.h>
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
26 #define FACTOR2 4297157
27 #define MEASURE_FREQ 327
28 #define TEMPERATURE_MIN -40
29 #define TEMPERATURE_HOT 85
30 #define TEMPERATURE_MAX 125
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
47 #if defined(CONFIG_MX6)
48 static int read_cpu_temperature(struct udevice *dev)
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;
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)
67 t1 = 25; /* t1 always 25C */
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
87 do_div(temp64, FACTOR1 * n1 - FACTOR2);
89 c2 = n1 * c1 + 1000 * t1;
92 * now we only use single measure, every time we read
93 * the temperature, we will power on/down anadig thermal
96 writel(TEMPSENSE0_POWER_DOWN, &anatop->tempsense0_clr);
97 writel(MISC0_REFTOP_SELBIASOFF, &anatop->ana_misc0_set);
99 /* setup measure freq */
100 reg = readl(&anatop->tempsense1);
101 reg &= ~TEMPSENSE1_MEASURE_FREQ;
103 writel(reg, &anatop->tempsense1);
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);
110 /* make sure that the latest temp is valid */
111 while ((readl(&anatop->tempsense0) &
112 TEMPSENSE0_FINISHED) == 0)
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);
121 /* milli_Tmeas = c2 - Nmeas * c1 */
122 temperature = (long)(c2 - n_meas * c1)/1000;
124 /* power down anatop thermal sensor */
125 writel(TEMPSENSE0_POWER_DOWN, &anatop->tempsense0_set);
126 writel(MISC0_REFTOP_SELBIASOFF, &anatop->ana_misc0_clr);
130 #elif defined(CONFIG_MX7)
131 static int read_cpu_temperature(struct udevice *dev)
133 unsigned int reg, tmp, start;
134 unsigned int raw_25c, te1;
136 unsigned int *priv = dev_get_priv(dev);
138 struct mxc_ccm_anatop_reg *ccm_anatop = (struct mxc_ccm_anatop_reg *)
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
148 raw_25c = fuse >> 21;
152 te1 = (fuse >> 9) & 0x1ff;
155 * now we only use single measure, every time we read
156 * the temperature, we will power on/down anadig thermal
159 writel(TEMPMON_HW_ANADIG_TEMPSENSE1_POWER_DOWN_MASK, &ccm_anatop->tempsense1_clr);
160 writel(PMU_REF_REFTOP_SELFBIASOFF_MASK, &ccm_anatop->ref_set);
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);
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);
172 start = get_timer(0);
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.
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));
185 writel(TEMPMON_HW_ANADIG_TEMPSENSE1_FINISHED_MASK, &ccm_anatop->tempsense1_clr);
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);
192 temperature = tmp - (te1 - raw_25c);
198 int imx_thermal_get_temp(struct udevice *dev, int *temp)
200 struct thermal_data *priv = dev_get_priv(dev);
203 cpu_tmp = read_cpu_temperature(dev);
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");
210 cpu_tmp = read_cpu_temperature(dev);
218 static const struct dm_thermal_ops imx_thermal_ops = {
219 .get_temp = imx_thermal_get_temp,
222 static int imx_thermal_probe(struct udevice *dev)
224 unsigned int fuse = ~0;
226 const struct imx_thermal_plat *pdata = dev_get_platdata(dev);
227 struct thermal_data *priv = dev_get_priv(dev);
229 /* Read Temperature calibration data fuse */
230 fuse_read(pdata->fuse_bank, pdata->fuse_word, &fuse);
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",
239 } else if (is_soc_type(MXC_SOC_MX7)) {
240 /* No Calibration data in FUSE? */
241 if ((fuse & 0x3ffff) == 0)
243 /* We do not support 105C TE2 */
244 if (((fuse & 0x1c0000) >> 18) == 0x6)
248 /* set critical cooling temp */
249 get_cpu_temp_grade(&priv->minc, &priv->maxc);
250 priv->critical = priv->maxc - TEMPERATURE_HOT_DELTA;
253 enable_thermal_clk();
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,