1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Broadcom STB AVS TMON thermal sensor driver
4 *
5 * Copyright (c) 2015-2017 Broadcom
6 */
7
8 #define DRV_NAME "brcmstb_thermal"
9
10 #define pr_fmt(fmt) DRV_NAME ": " fmt
11
12 #include <linux/bitops.h>
13 #include <linux/device.h>
14 #include <linux/err.h>
15 #include <linux/io.h>
16 #include <linux/irqreturn.h>
17 #include <linux/interrupt.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/of.h>
21 #include <linux/platform_device.h>
22 #include <linux/thermal.h>
23
24 #define AVS_TMON_STATUS 0x00
25 #define AVS_TMON_STATUS_valid_msk BIT(11)
26 #define AVS_TMON_STATUS_data_msk GENMASK(10, 1)
27 #define AVS_TMON_STATUS_data_shift 1
28
29 #define AVS_TMON_EN_OVERTEMP_RESET 0x04
30 #define AVS_TMON_EN_OVERTEMP_RESET_msk BIT(0)
31
32 #define AVS_TMON_RESET_THRESH 0x08
33 #define AVS_TMON_RESET_THRESH_msk GENMASK(10, 1)
34 #define AVS_TMON_RESET_THRESH_shift 1
35
36 #define AVS_TMON_INT_IDLE_TIME 0x10
37
38 #define AVS_TMON_EN_TEMP_INT_SRCS 0x14
39 #define AVS_TMON_EN_TEMP_INT_SRCS_high BIT(1)
40 #define AVS_TMON_EN_TEMP_INT_SRCS_low BIT(0)
41
42 #define AVS_TMON_INT_THRESH 0x18
43 #define AVS_TMON_INT_THRESH_high_msk GENMASK(26, 17)
44 #define AVS_TMON_INT_THRESH_high_shift 17
45 #define AVS_TMON_INT_THRESH_low_msk GENMASK(10, 1)
46 #define AVS_TMON_INT_THRESH_low_shift 1
47
48 #define AVS_TMON_TEMP_INT_CODE 0x1c
49 #define AVS_TMON_TP_TEST_ENABLE 0x20
50
51 /* Default coefficients */
52 #define AVS_TMON_TEMP_SLOPE 487
53 #define AVS_TMON_TEMP_OFFSET 410040
54
55 /* HW related temperature constants */
56 #define AVS_TMON_TEMP_MAX 0x3ff
57 #define AVS_TMON_TEMP_MIN -88161
58 #define AVS_TMON_TEMP_MASK AVS_TMON_TEMP_MAX
59
60 enum avs_tmon_trip_type {
61 TMON_TRIP_TYPE_LOW = 0,
62 TMON_TRIP_TYPE_HIGH,
63 TMON_TRIP_TYPE_RESET,
64 TMON_TRIP_TYPE_MAX,
65 };
66
67 struct avs_tmon_trip {
68 /* HW bit to enable the trip */
69 u32 enable_offs;
70 u32 enable_mask;
71
72 /* HW field to read the trip temperature */
73 u32 reg_offs;
74 u32 reg_msk;
75 int reg_shift;
76 };
77
78 static struct avs_tmon_trip avs_tmon_trips[] = {
79 /* Trips when temperature is below threshold */
80 [TMON_TRIP_TYPE_LOW] = {
81 .enable_offs = AVS_TMON_EN_TEMP_INT_SRCS,
82 .enable_mask = AVS_TMON_EN_TEMP_INT_SRCS_low,
83 .reg_offs = AVS_TMON_INT_THRESH,
84 .reg_msk = AVS_TMON_INT_THRESH_low_msk,
85 .reg_shift = AVS_TMON_INT_THRESH_low_shift,
86 },
87 /* Trips when temperature is above threshold */
88 [TMON_TRIP_TYPE_HIGH] = {
89 .enable_offs = AVS_TMON_EN_TEMP_INT_SRCS,
90 .enable_mask = AVS_TMON_EN_TEMP_INT_SRCS_high,
91 .reg_offs = AVS_TMON_INT_THRESH,
92 .reg_msk = AVS_TMON_INT_THRESH_high_msk,
93 .reg_shift = AVS_TMON_INT_THRESH_high_shift,
94 },
95 /* Automatically resets chip when above threshold */
96 [TMON_TRIP_TYPE_RESET] = {
97 .enable_offs = AVS_TMON_EN_OVERTEMP_RESET,
98 .enable_mask = AVS_TMON_EN_OVERTEMP_RESET_msk,
99 .reg_offs = AVS_TMON_RESET_THRESH,
100 .reg_msk = AVS_TMON_RESET_THRESH_msk,
101 .reg_shift = AVS_TMON_RESET_THRESH_shift,
102 },
103 };
104
105 struct brcmstb_thermal_params {
106 unsigned int offset;
107 unsigned int mult;
108 const struct thermal_zone_device_ops *of_ops;
109 };
110
111 struct brcmstb_thermal_priv {
112 void __iomem *tmon_base;
113 struct device *dev;
114 struct thermal_zone_device *thermal;
115 /* Process specific thermal parameters used for calculations */
116 const struct brcmstb_thermal_params *temp_params;
117 };
118
119 /* Convert a HW code to a temperature reading (millidegree celsius) */
avs_tmon_code_to_temp(struct brcmstb_thermal_priv * priv,u32 code)120 static inline int avs_tmon_code_to_temp(struct brcmstb_thermal_priv *priv,
121 u32 code)
122 {
123 int offset = priv->temp_params->offset;
124 int mult = priv->temp_params->mult;
125
126 return (offset - (int)((code & AVS_TMON_TEMP_MASK) * mult));
127 }
128
129 /*
130 * Convert a temperature value (millidegree celsius) to a HW code
131 *
132 * @temp: temperature to convert
133 * @low: if true, round toward the low side
134 */
avs_tmon_temp_to_code(struct brcmstb_thermal_priv * priv,int temp,bool low)135 static inline u32 avs_tmon_temp_to_code(struct brcmstb_thermal_priv *priv,
136 int temp, bool low)
137 {
138 int offset = priv->temp_params->offset;
139 int mult = priv->temp_params->mult;
140
141 if (temp < AVS_TMON_TEMP_MIN)
142 return AVS_TMON_TEMP_MAX; /* Maximum code value */
143
144 if (temp >= offset)
145 return 0; /* Minimum code value */
146
147 if (low)
148 return (u32)(DIV_ROUND_UP(offset - temp, mult));
149 else
150 return (u32)((offset - temp) / mult);
151 }
152
brcmstb_get_temp(struct thermal_zone_device * tz,int * temp)153 static int brcmstb_get_temp(struct thermal_zone_device *tz, int *temp)
154 {
155 struct brcmstb_thermal_priv *priv = thermal_zone_device_priv(tz);
156 u32 val;
157 long t;
158
159 val = __raw_readl(priv->tmon_base + AVS_TMON_STATUS);
160
161 if (!(val & AVS_TMON_STATUS_valid_msk))
162 return -EIO;
163
164 val = (val & AVS_TMON_STATUS_data_msk) >> AVS_TMON_STATUS_data_shift;
165
166 t = avs_tmon_code_to_temp(priv, val);
167 if (t < 0)
168 *temp = 0;
169 else
170 *temp = t;
171
172 return 0;
173 }
174
avs_tmon_trip_enable(struct brcmstb_thermal_priv * priv,enum avs_tmon_trip_type type,int en)175 static void avs_tmon_trip_enable(struct brcmstb_thermal_priv *priv,
176 enum avs_tmon_trip_type type, int en)
177 {
178 struct avs_tmon_trip *trip = &avs_tmon_trips[type];
179 u32 val = __raw_readl(priv->tmon_base + trip->enable_offs);
180
181 dev_dbg(priv->dev, "%sable trip, type %d\n", en ? "en" : "dis", type);
182
183 if (en)
184 val |= trip->enable_mask;
185 else
186 val &= ~trip->enable_mask;
187
188 __raw_writel(val, priv->tmon_base + trip->enable_offs);
189 }
190
avs_tmon_get_trip_temp(struct brcmstb_thermal_priv * priv,enum avs_tmon_trip_type type)191 static int avs_tmon_get_trip_temp(struct brcmstb_thermal_priv *priv,
192 enum avs_tmon_trip_type type)
193 {
194 struct avs_tmon_trip *trip = &avs_tmon_trips[type];
195 u32 val = __raw_readl(priv->tmon_base + trip->reg_offs);
196
197 val &= trip->reg_msk;
198 val >>= trip->reg_shift;
199
200 return avs_tmon_code_to_temp(priv, val);
201 }
202
avs_tmon_set_trip_temp(struct brcmstb_thermal_priv * priv,enum avs_tmon_trip_type type,int temp)203 static void avs_tmon_set_trip_temp(struct brcmstb_thermal_priv *priv,
204 enum avs_tmon_trip_type type,
205 int temp)
206 {
207 struct avs_tmon_trip *trip = &avs_tmon_trips[type];
208 u32 val, orig;
209
210 dev_dbg(priv->dev, "set temp %d to %d\n", type, temp);
211
212 /* round toward low temp for the low interrupt */
213 val = avs_tmon_temp_to_code(priv, temp,
214 type == TMON_TRIP_TYPE_LOW);
215
216 val <<= trip->reg_shift;
217 val &= trip->reg_msk;
218
219 orig = __raw_readl(priv->tmon_base + trip->reg_offs);
220 orig &= ~trip->reg_msk;
221 orig |= val;
222 __raw_writel(orig, priv->tmon_base + trip->reg_offs);
223 }
224
avs_tmon_get_intr_temp(struct brcmstb_thermal_priv * priv)225 static int avs_tmon_get_intr_temp(struct brcmstb_thermal_priv *priv)
226 {
227 u32 val;
228
229 val = __raw_readl(priv->tmon_base + AVS_TMON_TEMP_INT_CODE);
230 return avs_tmon_code_to_temp(priv, val);
231 }
232
brcmstb_tmon_irq_thread(int irq,void * data)233 static irqreturn_t brcmstb_tmon_irq_thread(int irq, void *data)
234 {
235 struct brcmstb_thermal_priv *priv = data;
236 int low, high, intr;
237
238 low = avs_tmon_get_trip_temp(priv, TMON_TRIP_TYPE_LOW);
239 high = avs_tmon_get_trip_temp(priv, TMON_TRIP_TYPE_HIGH);
240 intr = avs_tmon_get_intr_temp(priv);
241
242 dev_dbg(priv->dev, "low/intr/high: %d/%d/%d\n",
243 low, intr, high);
244
245 /* Disable high-temp until next threshold shift */
246 if (intr >= high)
247 avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_HIGH, 0);
248 /* Disable low-temp until next threshold shift */
249 if (intr <= low)
250 avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_LOW, 0);
251
252 /*
253 * Notify using the interrupt temperature, in case the temperature
254 * changes before it can next be read out
255 */
256 thermal_zone_device_update(priv->thermal, intr);
257
258 return IRQ_HANDLED;
259 }
260
brcmstb_set_trips(struct thermal_zone_device * tz,int low,int high)261 static int brcmstb_set_trips(struct thermal_zone_device *tz, int low, int high)
262 {
263 struct brcmstb_thermal_priv *priv = thermal_zone_device_priv(tz);
264
265 dev_dbg(priv->dev, "set trips %d <--> %d\n", low, high);
266
267 /*
268 * Disable low-temp if "low" is too small. As per thermal framework
269 * API, we use -INT_MAX rather than INT_MIN.
270 */
271 if (low <= -INT_MAX) {
272 avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_LOW, 0);
273 } else {
274 avs_tmon_set_trip_temp(priv, TMON_TRIP_TYPE_LOW, low);
275 avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_LOW, 1);
276 }
277
278 /* Disable high-temp if "high" is too big. */
279 if (high == INT_MAX) {
280 avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_HIGH, 0);
281 } else {
282 avs_tmon_set_trip_temp(priv, TMON_TRIP_TYPE_HIGH, high);
283 avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_HIGH, 1);
284 }
285
286 return 0;
287 }
288
289 static const struct thermal_zone_device_ops brcmstb_16nm_of_ops = {
290 .get_temp = brcmstb_get_temp,
291 };
292
293 static const struct brcmstb_thermal_params brcmstb_16nm_params = {
294 .offset = 457829,
295 .mult = 557,
296 .of_ops = &brcmstb_16nm_of_ops,
297 };
298
299 static const struct thermal_zone_device_ops brcmstb_28nm_of_ops = {
300 .get_temp = brcmstb_get_temp,
301 .set_trips = brcmstb_set_trips,
302 };
303
304 static const struct brcmstb_thermal_params brcmstb_28nm_params = {
305 .offset = 410040,
306 .mult = 487,
307 .of_ops = &brcmstb_28nm_of_ops,
308 };
309
310 static const struct of_device_id brcmstb_thermal_id_table[] = {
311 { .compatible = "brcm,avs-tmon-bcm7216", .data = &brcmstb_16nm_params },
312 { .compatible = "brcm,avs-tmon", .data = &brcmstb_28nm_params },
313 {},
314 };
315 MODULE_DEVICE_TABLE(of, brcmstb_thermal_id_table);
316
brcmstb_thermal_probe(struct platform_device * pdev)317 static int brcmstb_thermal_probe(struct platform_device *pdev)
318 {
319 const struct thermal_zone_device_ops *of_ops;
320 struct thermal_zone_device *thermal;
321 struct brcmstb_thermal_priv *priv;
322 int irq, ret;
323
324 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
325 if (!priv)
326 return -ENOMEM;
327
328 priv->temp_params = of_device_get_match_data(&pdev->dev);
329 if (!priv->temp_params)
330 return -EINVAL;
331
332 priv->tmon_base = devm_platform_get_and_ioremap_resource(pdev, 0, NULL);
333 if (IS_ERR(priv->tmon_base))
334 return PTR_ERR(priv->tmon_base);
335
336 priv->dev = &pdev->dev;
337 of_ops = priv->temp_params->of_ops;
338
339 thermal = devm_thermal_of_zone_register(&pdev->dev, 0, priv,
340 of_ops);
341 if (IS_ERR(thermal)) {
342 ret = PTR_ERR(thermal);
343 dev_err(&pdev->dev, "could not register sensor: %d\n", ret);
344 return ret;
345 }
346
347 priv->thermal = thermal;
348
349 irq = platform_get_irq_optional(pdev, 0);
350 if (irq >= 0) {
351 ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
352 brcmstb_tmon_irq_thread,
353 IRQF_ONESHOT,
354 DRV_NAME, priv);
355 if (ret < 0) {
356 dev_err(&pdev->dev, "could not request IRQ: %d\n", ret);
357 return ret;
358 }
359 }
360
361 dev_info(&pdev->dev, "registered AVS TMON of-sensor driver\n");
362
363 return 0;
364 }
365
366 static struct platform_driver brcmstb_thermal_driver = {
367 .probe = brcmstb_thermal_probe,
368 .driver = {
369 .name = DRV_NAME,
370 .of_match_table = brcmstb_thermal_id_table,
371 },
372 };
373 module_platform_driver(brcmstb_thermal_driver);
374
375 MODULE_LICENSE("GPL v2");
376 MODULE_AUTHOR("Brian Norris");
377 MODULE_DESCRIPTION("Broadcom STB AVS TMON thermal driver");
378