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 			debug("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 };
266