xref: /openbmc/u-boot/drivers/power/exynos-tmu.c (revision d6208a3c)
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 #include <asm/arch/power.h>
26 
27 #define TRIMINFO_RELOAD		1
28 #define CORE_EN			1
29 #define THERM_TRIP_EN		(1 << 12)
30 
31 #define INTEN_RISE0		1
32 #define INTEN_RISE1		(1 << 4)
33 #define INTEN_RISE2		(1 << 8)
34 #define INTEN_FALL0		(1 << 16)
35 #define INTEN_FALL1		(1 << 20)
36 #define INTEN_FALL2		(1 << 24)
37 
38 #define TRIM_INFO_MASK		0xff
39 
40 #define INTCLEAR_RISE0		1
41 #define INTCLEAR_RISE1		(1 << 4)
42 #define INTCLEAR_RISE2		(1 << 8)
43 #define INTCLEAR_FALL0		(1 << 16)
44 #define INTCLEAR_FALL1		(1 << 20)
45 #define INTCLEAR_FALL2		(1 << 24)
46 #define INTCLEARALL		(INTCLEAR_RISE0 | INTCLEAR_RISE1 | \
47 				 INTCLEAR_RISE2 | INTCLEAR_FALL0 | \
48 				 INTCLEAR_FALL1 | INTCLEAR_FALL2)
49 
50 /* Tmeperature threshold values for various thermal events */
51 struct temperature_params {
52 	/* minimum value in temperature code range */
53 	unsigned int min_val;
54 	/* maximum value in temperature code range */
55 	unsigned int max_val;
56 	/* temperature threshold to start warning */
57 	unsigned int start_warning;
58 	/* temperature threshold CPU tripping */
59 	unsigned int start_tripping;
60 	/* temperature threshold for HW tripping */
61 	unsigned int hardware_tripping;
62 };
63 
64 /* Pre-defined values and thresholds for calibration of current temperature */
65 struct tmu_data {
66 	/* pre-defined temperature thresholds */
67 	struct temperature_params ts;
68 	/* pre-defined efuse range minimum value */
69 	unsigned int efuse_min_value;
70 	/* pre-defined efuse value for temperature calibration */
71 	unsigned int efuse_value;
72 	/* pre-defined efuse range maximum value */
73 	unsigned int efuse_max_value;
74 	/* current temperature sensing slope */
75 	unsigned int slope;
76 };
77 
78 /* TMU device specific details and status */
79 struct tmu_info {
80 	/* base Address for the TMU */
81 	unsigned tmu_base;
82 	/* pre-defined values for calibration and thresholds */
83 	struct tmu_data data;
84 	/* value required for triminfo_25 calibration */
85 	unsigned int te1;
86 	/* value required for triminfo_85 calibration */
87 	unsigned int te2;
88 	/* Value for measured data calibration */
89 	int dc_value;
90 	/* enum value indicating status of the TMU */
91 	int tmu_state;
92 };
93 
94 /* Global struct tmu_info variable to store init values */
95 static struct tmu_info gbl_info;
96 
97 /*
98  * Get current temperature code from register,
99  * then calculate and calibrate it's value
100  * in degree celsius.
101  *
102  * @return	current temperature of the chip as sensed by TMU
103  */
104 static int get_cur_temp(struct tmu_info *info)
105 {
106 	int cur_temp;
107 	struct exynos5_tmu_reg *reg = (struct exynos5_tmu_reg *)info->tmu_base;
108 
109 	/*
110 	 * Temperature code range between min 25 and max 125.
111 	 * May run more than once for first call as initial sensing
112 	 * has not yet happened.
113 	 */
114 	do {
115 		cur_temp = readl(&reg->current_temp) & 0xff;
116 	} while (cur_temp == 0 && info->tmu_state == TMU_STATUS_NORMAL);
117 
118 	/* Calibrate current temperature */
119 	cur_temp = cur_temp - info->te1 + info->dc_value;
120 
121 	return cur_temp;
122 }
123 
124 /*
125  * Monitors status of the TMU device and exynos temperature
126  *
127  * @param temp	pointer to the current temperature value
128  * @return	enum tmu_status_t value, code indicating event to execute
129  */
130 enum tmu_status_t tmu_monitor(int *temp)
131 {
132 	int cur_temp;
133 	struct tmu_data *data = &gbl_info.data;
134 
135 	if (gbl_info.tmu_state == TMU_STATUS_INIT)
136 		return TMU_STATUS_INIT;
137 
138 	/* Read current temperature of the SOC */
139 	cur_temp = get_cur_temp(&gbl_info);
140 	*temp = cur_temp;
141 
142 	/* Temperature code lies between min 25 and max 125 */
143 	if (cur_temp >= data->ts.start_tripping &&
144 			cur_temp <= data->ts.max_val) {
145 		return TMU_STATUS_TRIPPED;
146 	} else if (cur_temp >= data->ts.start_warning) {
147 		return TMU_STATUS_WARNING;
148 	} else if (cur_temp < data->ts.start_warning &&
149 			cur_temp >= data->ts.min_val) {
150 		return TMU_STATUS_NORMAL;
151 	} else {
152 		/* Temperature code does not lie between min 25 and max 125 */
153 		gbl_info.tmu_state = TMU_STATUS_INIT;
154 		debug("EXYNOS_TMU: Thermal reading failed\n");
155 		return TMU_STATUS_INIT;
156 	}
157 }
158 
159 /*
160  * Get TMU specific pre-defined values from FDT
161  *
162  * @param info	pointer to the tmu_info struct
163  * @param blob  FDT blob
164  * @return	int value, 0 for success
165  */
166 static int get_tmu_fdt_values(struct tmu_info *info, const void *blob)
167 {
168 #ifdef CONFIG_OF_CONTROL
169 	int node;
170 	int error = 0;
171 
172 	/* Get the node from FDT for TMU */
173 	node = fdtdec_next_compatible(blob, 0,
174 				      COMPAT_SAMSUNG_EXYNOS_TMU);
175 	if (node < 0) {
176 		debug("EXYNOS_TMU: No node for tmu in device tree\n");
177 		return -1;
178 	}
179 
180 	/*
181 	 * Get the pre-defined TMU specific values from FDT.
182 	 * All of these are expected to be correct otherwise
183 	 * miscalculation of register values in tmu_setup_parameters
184 	 * may result in misleading current temperature.
185 	 */
186 	info->tmu_base = fdtdec_get_addr(blob, node, "reg");
187 	if (info->tmu_base == FDT_ADDR_T_NONE) {
188 		debug("%s: Missing tmu-base\n", __func__);
189 		return -1;
190 	}
191 	info->data.ts.min_val = fdtdec_get_int(blob,
192 				node, "samsung,min-temp", -1);
193 	error |= info->data.ts.min_val;
194 	info->data.ts.max_val = fdtdec_get_int(blob,
195 				node, "samsung,max-temp", -1);
196 	error |= info->data.ts.max_val;
197 	info->data.ts.start_warning = fdtdec_get_int(blob,
198 				node, "samsung,start-warning", -1);
199 	error |= info->data.ts.start_warning;
200 	info->data.ts.start_tripping = fdtdec_get_int(blob,
201 				node, "samsung,start-tripping", -1);
202 	error |= info->data.ts.start_tripping;
203 	info->data.ts.hardware_tripping = fdtdec_get_int(blob,
204 				node, "samsung,hw-tripping", -1);
205 	error |= info->data.ts.hardware_tripping;
206 	info->data.efuse_min_value = fdtdec_get_int(blob,
207 				node, "samsung,efuse-min-value", -1);
208 	error |= info->data.efuse_min_value;
209 	info->data.efuse_value = fdtdec_get_int(blob,
210 				node, "samsung,efuse-value", -1);
211 	error |= info->data.efuse_value;
212 	info->data.efuse_max_value = fdtdec_get_int(blob,
213 				node, "samsung,efuse-max-value", -1);
214 	error |= info->data.efuse_max_value;
215 	info->data.slope = fdtdec_get_int(blob,
216 				node, "samsung,slope", -1);
217 	error |= info->data.slope;
218 	info->dc_value = fdtdec_get_int(blob,
219 				node, "samsung,dc-value", -1);
220 	error |= info->dc_value;
221 
222 	if (error == -1) {
223 		debug("fail to get tmu node properties\n");
224 		return -1;
225 	}
226 #endif
227 
228 	return 0;
229 }
230 
231 /*
232  * Calibrate and calculate threshold values and
233  * enable interrupt levels
234  *
235  * @param	info pointer to the tmu_info struct
236  */
237 static void tmu_setup_parameters(struct tmu_info *info)
238 {
239 	unsigned int te_code, con;
240 	unsigned int warning_code, trip_code, hwtrip_code;
241 	unsigned int cooling_temp;
242 	unsigned int rising_value;
243 	struct tmu_data *data = &info->data;
244 	struct exynos5_tmu_reg *reg = (struct exynos5_tmu_reg *)info->tmu_base;
245 
246 	/* Must reload for reading efuse value from triminfo register */
247 	writel(TRIMINFO_RELOAD, &reg->triminfo_control);
248 
249 	/* Get the compensation parameter */
250 	te_code = readl(&reg->triminfo);
251 	info->te1 = te_code & TRIM_INFO_MASK;
252 	info->te2 = ((te_code >> 8) & TRIM_INFO_MASK);
253 
254 	if ((data->efuse_min_value > info->te1) ||
255 			(info->te1 > data->efuse_max_value)
256 			||  (info->te2 != 0))
257 		info->te1 = data->efuse_value;
258 
259 	/* Get RISING & FALLING Threshold value */
260 	warning_code = data->ts.start_warning
261 			+ info->te1 - info->dc_value;
262 	trip_code = data->ts.start_tripping
263 			+ info->te1 - info->dc_value;
264 	hwtrip_code = data->ts.hardware_tripping
265 			+ info->te1 - info->dc_value;
266 
267 	cooling_temp = 0;
268 
269 	rising_value = ((warning_code << 8) |
270 			(trip_code << 16) |
271 			(hwtrip_code << 24));
272 
273 	/* Set interrupt level */
274 	writel(rising_value, &reg->threshold_temp_rise);
275 	writel(cooling_temp, &reg->threshold_temp_fall);
276 
277 	/*
278 	 * Init TMU control tuning parameters
279 	 * [28:24] VREF - Voltage reference
280 	 * [15:13] THERM_TRIP_MODE - Tripping mode
281 	 * [12] THERM_TRIP_EN - Thermal tripping enable
282 	 * [11:8] BUF_SLOPE_SEL - Gain of amplifier
283 	 * [6] THERM_TRIP_BY_TQ_EN - Tripping by TQ pin
284 	 */
285 	writel(data->slope, &reg->tmu_control);
286 
287 	writel(INTCLEARALL, &reg->intclear);
288 
289 	/* TMU core enable */
290 	con = readl(&reg->tmu_control);
291 	con |= THERM_TRIP_EN | CORE_EN;
292 
293 	writel(con, &reg->tmu_control);
294 
295 	/* Enable HW thermal trip */
296 	set_hw_thermal_trip();
297 
298 	/* LEV1 LEV2 interrupt enable */
299 	writel(INTEN_RISE1 | INTEN_RISE2, &reg->inten);
300 }
301 
302 /*
303  * Initialize TMU device
304  *
305  * @param blob  FDT blob
306  * @return	int value, 0 for success
307  */
308 int tmu_init(const void *blob)
309 {
310 	gbl_info.tmu_state = TMU_STATUS_INIT;
311 	if (get_tmu_fdt_values(&gbl_info, blob) < 0)
312 		goto ret;
313 
314 	tmu_setup_parameters(&gbl_info);
315 	gbl_info.tmu_state = TMU_STATUS_NORMAL;
316 ret:
317 
318 	return gbl_info.tmu_state;
319 }
320