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 <log.h>
24 #include <tmu.h>
25 #include <asm/arch/tmu.h>
26 #include <asm/arch/power.h>
27 
28 #define TRIMINFO_RELOAD		1
29 #define CORE_EN			1
30 #define THERM_TRIP_EN		(1 << 12)
31 
32 #define INTEN_RISE0		1
33 #define INTEN_RISE1		(1 << 4)
34 #define INTEN_RISE2		(1 << 8)
35 #define INTEN_FALL0		(1 << 16)
36 #define INTEN_FALL1		(1 << 20)
37 #define INTEN_FALL2		(1 << 24)
38 
39 #define TRIM_INFO_MASK		0xff
40 
41 #define INTCLEAR_RISE0		1
42 #define INTCLEAR_RISE1		(1 << 4)
43 #define INTCLEAR_RISE2		(1 << 8)
44 #define INTCLEAR_FALL0		(1 << 16)
45 #define INTCLEAR_FALL1		(1 << 20)
46 #define INTCLEAR_FALL2		(1 << 24)
47 #define INTCLEARALL		(INTCLEAR_RISE0 | INTCLEAR_RISE1 | \
48 				 INTCLEAR_RISE2 | INTCLEAR_FALL0 | \
49 				 INTCLEAR_FALL1 | INTCLEAR_FALL2)
50 
51 /* Tmeperature threshold values for various thermal events */
52 struct temperature_params {
53 	/* minimum value in temperature code range */
54 	unsigned min_val;
55 	/* maximum value in temperature code range */
56 	unsigned max_val;
57 	/* temperature threshold to start warning */
58 	unsigned start_warning;
59 	/* temperature threshold CPU tripping */
60 	unsigned start_tripping;
61 	/* temperature threshold for HW tripping */
62 	unsigned hardware_tripping;
63 };
64 
65 /* Pre-defined values and thresholds for calibration of current temperature */
66 struct tmu_data {
67 	/* pre-defined temperature thresholds */
68 	struct temperature_params ts;
69 	/* pre-defined efuse range minimum value */
70 	unsigned efuse_min_value;
71 	/* pre-defined efuse value for temperature calibration */
72 	unsigned efuse_value;
73 	/* pre-defined efuse range maximum value */
74 	unsigned efuse_max_value;
75 	/* current temperature sensing slope */
76 	unsigned slope;
77 };
78 
79 /* TMU device specific details and status */
80 struct tmu_info {
81 	/* base Address for the TMU */
82 	struct exynos5_tmu_reg *tmu_base;
83 	/* mux Address for the TMU */
84 	int tmu_mux;
85 	/* pre-defined values for calibration and thresholds */
86 	struct tmu_data data;
87 	/* value required for triminfo_25 calibration */
88 	unsigned te1;
89 	/* value required for triminfo_85 calibration */
90 	unsigned te2;
91 	/* Value for measured data calibration */
92 	int dc_value;
93 	/* enum value indicating status of the TMU */
94 	int tmu_state;
95 };
96 
97 /* Global struct tmu_info variable to store init values */
98 static struct tmu_info gbl_info;
99 
100 /*
101  * Get current temperature code from register,
102  * then calculate and calibrate it's value
103  * in degree celsius.
104  *
105  * @return	current temperature of the chip as sensed by TMU
106  */
get_cur_temp(struct tmu_info * info)107 static int get_cur_temp(struct tmu_info *info)
108 {
109 	struct exynos5_tmu_reg *reg = info->tmu_base;
110 	ulong start;
111 	int cur_temp = 0;
112 
113 	/*
114 	 * Temperature code range between min 25 and max 125.
115 	 * May run more than once for first call as initial sensing
116 	 * has not yet happened.
117 	 */
118 	if (info->tmu_state == TMU_STATUS_NORMAL) {
119 		start = get_timer(0);
120 		do {
121 			cur_temp = readl(&reg->current_temp) & 0xff;
122 		} while ((cur_temp == 0) || (get_timer(start) > 100));
123 	}
124 
125 	if (cur_temp == 0)
126 		return cur_temp;
127 
128 	/* Calibrate current temperature */
129 	cur_temp = cur_temp - info->te1 + info->dc_value;
130 
131 	return cur_temp;
132 }
133 
134 /*
135  * Monitors status of the TMU device and exynos temperature
136  *
137  * @param temp	pointer to the current temperature value
138  * @return	enum tmu_status_t value, code indicating event to execute
139  */
tmu_monitor(int * temp)140 enum tmu_status_t tmu_monitor(int *temp)
141 {
142 	int cur_temp;
143 	struct tmu_data *data = &gbl_info.data;
144 
145 	if (gbl_info.tmu_state == TMU_STATUS_INIT)
146 		return TMU_STATUS_INIT;
147 
148 	/* Read current temperature of the SOC */
149 	cur_temp = get_cur_temp(&gbl_info);
150 
151 	if (!cur_temp)
152 		goto out;
153 
154 	*temp = cur_temp;
155 
156 	/* Temperature code lies between min 25 and max 125 */
157 	if ((cur_temp >= data->ts.start_tripping) &&
158 	    (cur_temp <= data->ts.max_val))
159 		return TMU_STATUS_TRIPPED;
160 
161 	if (cur_temp >= data->ts.start_warning)
162 		return TMU_STATUS_WARNING;
163 
164 	if ((cur_temp < data->ts.start_warning) &&
165 	    (cur_temp >= data->ts.min_val))
166 		return TMU_STATUS_NORMAL;
167 
168  out:
169 	/* Temperature code does not lie between min 25 and max 125 */
170 	gbl_info.tmu_state = TMU_STATUS_INIT;
171 	debug("EXYNOS_TMU: Thermal reading failed\n");
172 	return TMU_STATUS_INIT;
173 }
174 
175 /*
176  * Get TMU specific pre-defined values from FDT
177  *
178  * @param info	pointer to the tmu_info struct
179  * @param blob  FDT blob
180  * @return	int value, 0 for success
181  */
get_tmu_fdt_values(struct tmu_info * info,const void * blob)182 static int get_tmu_fdt_values(struct tmu_info *info, const void *blob)
183 {
184 #if CONFIG_IS_ENABLED(OF_CONTROL)
185 	fdt_addr_t addr;
186 	int node;
187 	int error = 0;
188 
189 	/* Get the node from FDT for TMU */
190 	node = fdtdec_next_compatible(blob, 0,
191 				      COMPAT_SAMSUNG_EXYNOS_TMU);
192 	if (node < 0) {
193 		debug("EXYNOS_TMU: No node for tmu in device tree\n");
194 		return -ENODEV;
195 	}
196 
197 	/*
198 	 * Get the pre-defined TMU specific values from FDT.
199 	 * All of these are expected to be correct otherwise
200 	 * miscalculation of register values in tmu_setup_parameters
201 	 * may result in misleading current temperature.
202 	 */
203 	addr = fdtdec_get_addr(blob, node, "reg");
204 	if (addr == FDT_ADDR_T_NONE) {
205 		debug("%s: Missing tmu-base\n", __func__);
206 		return -ENODEV;
207 	}
208 	info->tmu_base = (struct exynos5_tmu_reg *)addr;
209 
210 	/* Optional field. */
211 	info->tmu_mux = fdtdec_get_int(blob,
212 				node, "samsung,mux", -1);
213 	/* Take default value as per the user manual b(110) */
214 	if (info->tmu_mux == -1)
215 		info->tmu_mux = 0x6;
216 
217 	info->data.ts.min_val = fdtdec_get_int(blob,
218 				node, "samsung,min-temp", -1);
219 	error |= (info->data.ts.min_val == -1);
220 	info->data.ts.max_val = fdtdec_get_int(blob,
221 				node, "samsung,max-temp", -1);
222 	error |= (info->data.ts.max_val == -1);
223 	info->data.ts.start_warning = fdtdec_get_int(blob,
224 				node, "samsung,start-warning", -1);
225 	error |= (info->data.ts.start_warning == -1);
226 	info->data.ts.start_tripping = fdtdec_get_int(blob,
227 				node, "samsung,start-tripping", -1);
228 	error |= (info->data.ts.start_tripping == -1);
229 	info->data.ts.hardware_tripping = fdtdec_get_int(blob,
230 				node, "samsung,hw-tripping", -1);
231 	error |= (info->data.ts.hardware_tripping == -1);
232 	info->data.efuse_min_value = fdtdec_get_int(blob,
233 				node, "samsung,efuse-min-value", -1);
234 	error |= (info->data.efuse_min_value == -1);
235 	info->data.efuse_value = fdtdec_get_int(blob,
236 				node, "samsung,efuse-value", -1);
237 	error |= (info->data.efuse_value == -1);
238 	info->data.efuse_max_value = fdtdec_get_int(blob,
239 				node, "samsung,efuse-max-value", -1);
240 	error |= (info->data.efuse_max_value == -1);
241 	info->data.slope = fdtdec_get_int(blob,
242 				node, "samsung,slope", -1);
243 	error |= (info->data.slope == -1);
244 	info->dc_value = fdtdec_get_int(blob,
245 				node, "samsung,dc-value", -1);
246 	error |= (info->dc_value == -1);
247 
248 	if (error) {
249 		debug("fail to get tmu node properties\n");
250 		return -EINVAL;
251 	}
252 #else
253 	/* Non DT support may never be added. Just in case  */
254 	return -ENODEV;
255 #endif
256 
257 	return 0;
258 }
259 
260 /*
261  * Calibrate and calculate threshold values and
262  * enable interrupt levels
263  *
264  * @param	info pointer to the tmu_info struct
265  */
tmu_setup_parameters(struct tmu_info * info)266 static void tmu_setup_parameters(struct tmu_info *info)
267 {
268 	unsigned te_code, con;
269 	unsigned warning_code, trip_code, hwtrip_code;
270 	unsigned cooling_temp;
271 	unsigned rising_value;
272 	struct tmu_data *data = &info->data;
273 	struct exynos5_tmu_reg *reg = info->tmu_base;
274 
275 	/* Must reload for reading efuse value from triminfo register */
276 	writel(TRIMINFO_RELOAD, &reg->triminfo_control);
277 
278 	/* Get the compensation parameter */
279 	te_code = readl(&reg->triminfo);
280 	info->te1 = te_code & TRIM_INFO_MASK;
281 	info->te2 = ((te_code >> 8) & TRIM_INFO_MASK);
282 
283 	if ((data->efuse_min_value > info->te1) ||
284 			(info->te1 > data->efuse_max_value)
285 			||  (info->te2 != 0))
286 		info->te1 = data->efuse_value;
287 
288 	/* Get RISING & FALLING Threshold value */
289 	warning_code = data->ts.start_warning
290 			+ info->te1 - info->dc_value;
291 	trip_code = data->ts.start_tripping
292 			+ info->te1 - info->dc_value;
293 	hwtrip_code = data->ts.hardware_tripping
294 			+ info->te1 - info->dc_value;
295 
296 	cooling_temp = 0;
297 
298 	rising_value = ((warning_code << 8) |
299 			(trip_code << 16) |
300 			(hwtrip_code << 24));
301 
302 	/* Set interrupt level */
303 	writel(rising_value, &reg->threshold_temp_rise);
304 	writel(cooling_temp, &reg->threshold_temp_fall);
305 
306 	/*
307 	 * Init TMU control tuning parameters
308 	 * [28:24] VREF - Voltage reference
309 	 * [15:13] THERM_TRIP_MODE - Tripping mode
310 	 * [12] THERM_TRIP_EN - Thermal tripping enable
311 	 * [11:8] BUF_SLOPE_SEL - Gain of amplifier
312 	 * [6] THERM_TRIP_BY_TQ_EN - Tripping by TQ pin
313 	 */
314 	writel(data->slope, &reg->tmu_control);
315 
316 	writel(INTCLEARALL, &reg->intclear);
317 
318 	/* TMU core enable */
319 	con = readl(&reg->tmu_control);
320 	con |= THERM_TRIP_EN | CORE_EN | (info->tmu_mux << 20);
321 
322 	writel(con, &reg->tmu_control);
323 
324 	/* Enable HW thermal trip */
325 	set_hw_thermal_trip();
326 
327 	/* LEV1 LEV2 interrupt enable */
328 	writel(INTEN_RISE1 | INTEN_RISE2, &reg->inten);
329 }
330 
331 /*
332  * Initialize TMU device
333  *
334  * @param blob  FDT blob
335  * @return	int value, 0 for success
336  */
tmu_init(const void * blob)337 int tmu_init(const void *blob)
338 {
339 	gbl_info.tmu_state = TMU_STATUS_INIT;
340 	if (get_tmu_fdt_values(&gbl_info, blob) < 0)
341 		goto ret;
342 
343 	tmu_setup_parameters(&gbl_info);
344 	gbl_info.tmu_state = TMU_STATUS_NORMAL;
345 ret:
346 	return gbl_info.tmu_state;
347 }
348