1 // SPDX-License-Identifier: GPL-2.0+
3 * (C) Copyright 2014 Freescale Semiconductor, Inc.
4 * Author: Nitin Garg <nitin.garg@freescale.com>
5 * Ye Li <Ye.Li@freescale.com>
13 #include <asm/arch/clock.h>
14 #include <asm/arch/sys_proto.h>
18 #include <linux/delay.h>
19 #include <linux/math64.h>
21 #include <imx_thermal.h>
23 /* board will busyloop until this many degrees C below CPU max temperature */
24 #define TEMPERATURE_HOT_DELTA 5 /* CPU maxT - 5C */
25 #define FACTOR0 10000000
27 #define FACTOR2 4148468
28 #define OFFSET 3580661
29 #define MEASURE_FREQ 327
30 #define TEMPERATURE_MIN -40
31 #define TEMPERATURE_HOT 85
32 #define TEMPERATURE_MAX 125
34 #define TEMPSENSE0_TEMP_CNT_SHIFT 8
35 #define TEMPSENSE0_TEMP_CNT_MASK (0xfff << TEMPSENSE0_TEMP_CNT_SHIFT)
36 #define TEMPSENSE0_FINISHED (1 << 2)
37 #define TEMPSENSE0_MEASURE_TEMP (1 << 1)
38 #define TEMPSENSE0_POWER_DOWN (1 << 0)
39 #define MISC0_REFTOP_SELBIASOFF (1 << 3)
40 #define TEMPSENSE1_MEASURE_FREQ 0xffff
49 #if defined(CONFIG_MX6)
50 static int read_cpu_temperature(struct udevice *dev)
53 unsigned int reg, n_meas;
54 const struct imx_thermal_plat *pdata = dev_get_plat(dev);
55 struct anatop_regs *anatop = (struct anatop_regs *)pdata->regs;
56 struct thermal_data *priv = dev_get_priv(dev);
57 u32 fuse = priv->fuse;
65 * [31:20] - sensor value @ 25C
66 * We use universal formula now and only need sensor value @ 25C
67 * slope = 0.4445388 - (0.0016549 * 25C fuse)
70 t1 = 25; /* t1 always 25C */
73 * Derived from linear interpolation:
74 * slope = 0.4445388 - (0.0016549 * 25C fuse)
75 * slope = (FACTOR2 - FACTOR1 * n1) / FACTOR0
77 * offset = OFFSET / 1000000
78 * (Nmeas - n1) / (Tmeas - t1 - offset) = slope
79 * We want to reduce this down to the minimum computation necessary
80 * for each temperature read. Also, we want Tmeas in millicelsius
81 * and we don't want to lose precision from integer division. So...
82 * Tmeas = (Nmeas - n1) / slope + t1 + offset
83 * milli_Tmeas = 1000000 * (Nmeas - n1) / slope + 1000000 * t1 + OFFSET
84 * milli_Tmeas = -1000000 * (n1 - Nmeas) / slope + 1000000 * t1 + OFFSET
85 * Let constant c1 = (-1000000 / slope)
86 * milli_Tmeas = (n1 - Nmeas) * c1 + 1000000 * t1 + OFFSET
87 * Let constant c2 = n1 *c1 + 1000000 * t1
88 * milli_Tmeas = (c2 - Nmeas * c1) + OFFSET
89 * Tmeas = ((c2 - Nmeas * c1) + OFFSET) / 1000000
93 temp64 = div_s64_rem(temp64, FACTOR1 * n1 - FACTOR2, &rem);
95 c2 = n1 * c1 + 1000000 * t1;
98 * now we only use single measure, every time we read
99 * the temperature, we will power on/down anadig thermal
102 writel(TEMPSENSE0_POWER_DOWN, &anatop->tempsense0_clr);
103 writel(MISC0_REFTOP_SELBIASOFF, &anatop->ana_misc0_set);
105 /* setup measure freq */
106 reg = readl(&anatop->tempsense1);
107 reg &= ~TEMPSENSE1_MEASURE_FREQ;
109 writel(reg, &anatop->tempsense1);
111 /* start the measurement process */
112 writel(TEMPSENSE0_MEASURE_TEMP, &anatop->tempsense0_clr);
113 writel(TEMPSENSE0_FINISHED, &anatop->tempsense0_clr);
114 writel(TEMPSENSE0_MEASURE_TEMP, &anatop->tempsense0_set);
116 /* make sure that the latest temp is valid */
117 while ((readl(&anatop->tempsense0) &
118 TEMPSENSE0_FINISHED) == 0)
121 /* read temperature count */
122 reg = readl(&anatop->tempsense0);
123 n_meas = (reg & TEMPSENSE0_TEMP_CNT_MASK)
124 >> TEMPSENSE0_TEMP_CNT_SHIFT;
125 writel(TEMPSENSE0_FINISHED, &anatop->tempsense0_clr);
127 /* Tmeas = (c2 - Nmeas * c1 + OFFSET) / 1000000 */
128 temperature = div_s64_rem(c2 - n_meas * c1 + OFFSET, 1000000, &rem);
130 /* power down anatop thermal sensor */
131 writel(TEMPSENSE0_POWER_DOWN, &anatop->tempsense0_set);
132 writel(MISC0_REFTOP_SELBIASOFF, &anatop->ana_misc0_clr);
136 #elif defined(CONFIG_MX7)
137 static int read_cpu_temperature(struct udevice *dev)
139 unsigned int reg, tmp;
140 unsigned int raw_25c, te1;
142 unsigned int *priv = dev_get_priv(dev);
144 struct mxc_ccm_anatop_reg *ccm_anatop = (struct mxc_ccm_anatop_reg *)
148 * [31:21] sensor value @ 25C
149 * [20:18] hot temperature value
150 * [17:9] sensor value of room
151 * [8:0] sensor value of hot
154 raw_25c = fuse >> 21;
158 te1 = (fuse >> 9) & 0x1ff;
161 * now we only use single measure, every time we read
162 * the temperature, we will power on/down anadig thermal
165 writel(TEMPMON_HW_ANADIG_TEMPSENSE1_POWER_DOWN_MASK, &ccm_anatop->tempsense1_clr);
166 writel(PMU_REF_REFTOP_SELFBIASOFF_MASK, &ccm_anatop->ref_set);
168 /* write measure freq */
169 reg = readl(&ccm_anatop->tempsense1);
170 reg &= ~TEMPMON_HW_ANADIG_TEMPSENSE1_MEASURE_FREQ_MASK;
171 reg |= TEMPMON_HW_ANADIG_TEMPSENSE1_MEASURE_FREQ(MEASURE_FREQ);
172 writel(reg, &ccm_anatop->tempsense1);
174 writel(TEMPMON_HW_ANADIG_TEMPSENSE1_MEASURE_TEMP_MASK, &ccm_anatop->tempsense1_clr);
175 writel(TEMPMON_HW_ANADIG_TEMPSENSE1_FINISHED_MASK, &ccm_anatop->tempsense1_clr);
176 writel(TEMPMON_HW_ANADIG_TEMPSENSE1_MEASURE_TEMP_MASK, &ccm_anatop->tempsense1_set);
178 if (soc_rev() >= CHIP_REV_1_1) {
179 while ((readl(&ccm_anatop->tempsense1) &
180 TEMPMON_HW_ANADIG_TEMPSENSE1_FINISHED_MASK) == 0)
182 reg = readl(&ccm_anatop->tempsense1);
183 tmp = (reg & TEMPMON_HW_ANADIG_TEMPSENSE1_TEMP_VALUE_MASK)
184 >> TEMPMON_HW_ANADIG_TEMPSENSE1_TEMP_VALUE_SHIFT;
187 * Since we can not rely on finish bit, use 10ms
188 * delay to get temperature. From RM, 17us is
189 * enough to get data, but to gurantee to get
190 * the data, delay 10ms here.
193 reg = readl(&ccm_anatop->tempsense1);
194 tmp = (reg & TEMPMON_HW_ANADIG_TEMPSENSE1_TEMP_VALUE_MASK)
195 >> TEMPMON_HW_ANADIG_TEMPSENSE1_TEMP_VALUE_SHIFT;
198 writel(TEMPMON_HW_ANADIG_TEMPSENSE1_FINISHED_MASK, &ccm_anatop->tempsense1_clr);
200 /* power down anatop thermal sensor */
201 writel(TEMPMON_HW_ANADIG_TEMPSENSE1_POWER_DOWN_MASK, &ccm_anatop->tempsense1_set);
202 writel(PMU_REF_REFTOP_SELFBIASOFF_MASK, &ccm_anatop->ref_clr);
205 temperature = tmp - (te1 - raw_25c);
211 int imx_thermal_get_temp(struct udevice *dev, int *temp)
213 struct thermal_data *priv = dev_get_priv(dev);
216 cpu_tmp = read_cpu_temperature(dev);
218 while (cpu_tmp >= priv->critical) {
219 printf("CPU Temperature (%dC) too close to max (%dC)",
220 cpu_tmp, priv->maxc);
221 puts(" waiting...\n");
223 cpu_tmp = read_cpu_temperature(dev);
231 static const struct dm_thermal_ops imx_thermal_ops = {
232 .get_temp = imx_thermal_get_temp,
235 static int imx_thermal_probe(struct udevice *dev)
237 unsigned int fuse = ~0;
239 const struct imx_thermal_plat *pdata = dev_get_plat(dev);
240 struct thermal_data *priv = dev_get_priv(dev);
242 /* Read Temperature calibration data fuse */
243 fuse_read(pdata->fuse_bank, pdata->fuse_word, &fuse);
245 if (is_soc_type(MXC_SOC_MX6)) {
246 /* Check for valid fuse */
247 if (fuse == 0 || fuse == ~0) {
248 debug("CPU: Thermal invalid data, fuse: 0x%x\n",
252 } else if (is_soc_type(MXC_SOC_MX7)) {
253 /* No Calibration data in FUSE? */
254 if ((fuse & 0x3ffff) == 0)
256 /* We do not support 105C TE2 */
257 if (((fuse & 0x1c0000) >> 18) == 0x6)
261 /* set critical cooling temp */
262 get_cpu_temp_grade(&priv->minc, &priv->maxc);
263 priv->critical = priv->maxc - TEMPERATURE_HOT_DELTA;
266 enable_thermal_clk();
271 U_BOOT_DRIVER(imx_thermal) = {
272 .name = "imx_thermal",
273 .id = UCLASS_THERMAL,
274 .ops = &imx_thermal_ops,
275 .probe = imx_thermal_probe,
276 .priv_auto = sizeof(struct thermal_data),
277 .flags = DM_FLAG_PRE_RELOC,