xref: /linux/drivers/thermal/imx91_thermal.c (revision c4dde411bc366f568dbe33366253bbfea049e8ea)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright 2025 NXP.
4  */
5 
6 #include <linux/bitfield.h>
7 #include <linux/clk.h>
8 #include <linux/err.h>
9 #include <linux/interrupt.h>
10 #include <linux/iopoll.h>
11 #include <linux/nvmem-consumer.h>
12 #include <linux/module.h>
13 #include <linux/of.h>
14 #include <linux/of_device.h>
15 #include <linux/platform_device.h>
16 #include <linux/pm_runtime.h>
17 #include <linux/thermal.h>
18 #include <linux/units.h>
19 
20 #include "thermal_hwmon.h"
21 
22 #define REG_SET					0x4
23 #define REG_CLR					0x8
24 #define REG_TOG					0xc
25 
26 #define IMX91_TMU_CTRL0				0x0
27 #define   IMX91_TMU_CTRL0_THR1_IE		BIT(9)
28 #define   IMX91_TMU_CTRL0_THR1_MASK		GENMASK(3, 2)
29 #define   IMX91_TMU_CTRL0_CLR_FLT1		BIT(21)
30 
31 #define IMX91_TMU_THR_MODE_LE			0
32 #define IMX91_TMU_THR_MODE_GE			1
33 
34 #define IMX91_TMU_STAT0				0x10
35 #define   IMX91_TMU_STAT0_THR1_IF		BIT(9)
36 #define   IMX91_TMU_STAT0_THR1_STAT		BIT(13)
37 #define   IMX91_TMU_STAT0_DRDY0_IF_MASK		BIT(16)
38 
39 #define IMX91_TMU_DATA0				0x20
40 
41 #define IMX91_TMU_CTRL1				0x200
42 #define IMX91_TMU_CTRL1_EN			BIT(31)
43 #define IMX91_TMU_CTRL1_START			BIT(30)
44 #define IMX91_TMU_CTRL1_STOP			BIT(29)
45 #define IMX91_TMU_CTRL1_RES_MASK		GENMASK(19, 18)
46 #define IMX91_TMU_CTRL1_MEAS_MODE_MASK		GENMASK(25, 24)
47 #define   IMX91_TMU_CTRL1_MEAS_MODE_SINGLE	0
48 #define   IMX91_TMU_CTRL1_MEAS_MODE_CONTINUES	1
49 #define   IMX91_TMU_CTRL1_MEAS_MODE_PERIODIC	2
50 
51 #define IMX91_TMU_THR_CTRL01			0x30
52 #define   IMX91_TMU_THR_CTRL01_THR1_MASK	GENMASK(31, 16)
53 
54 #define IMX91_TMU_REF_DIV			0x280
55 #define IMX91_TMU_DIV_EN			BIT(31)
56 #define IMX91_TMU_DIV_MASK			GENMASK(23, 16)
57 #define IMX91_TMU_DIV_MAX			255
58 
59 #define IMX91_TMU_PUD_ST_CTRL			0x2b0
60 #define IMX91_TMU_PUDL_MASK			GENMASK(23, 16)
61 
62 #define IMX91_TMU_TRIM1				0x2e0
63 #define IMX91_TMU_TRIM2				0x2f0
64 
65 #define IMX91_TMU_TEMP_LOW_LIMIT		-40000
66 #define IMX91_TMU_TEMP_HIGH_LIMIT		125000
67 
68 #define IMX91_TMU_DEFAULT_TRIM1_CONFIG		0xb561bc2d
69 #define IMX91_TMU_DEFAULT_TRIM2_CONFIG		0x65d4
70 
71 #define IMX91_TMU_PERIOD_CTRL			0x270
72 #define   IMX91_TMU_PERIOD_CTRL_MEAS_MASK	GENMASK(23, 0)
73 
74 #define IMX91_TMP_FRAC				64
75 
76 struct imx91_tmu {
77 	void __iomem *base;
78 	struct clk *clk;
79 	struct device *dev;
80 	struct thermal_zone_device *tzd;
81 };
82 
83 static void imx91_tmu_start(struct imx91_tmu *tmu, bool start)
84 {
85 	u32 val = start ? IMX91_TMU_CTRL1_START : IMX91_TMU_CTRL1_STOP;
86 
87 	writel_relaxed(val, tmu->base + IMX91_TMU_CTRL1 + REG_SET);
88 }
89 
90 static void imx91_tmu_enable(struct imx91_tmu *tmu, bool enable)
91 {
92 	u32 reg = IMX91_TMU_CTRL1;
93 
94 	reg += enable ? REG_SET : REG_CLR;
95 
96 	writel_relaxed(IMX91_TMU_CTRL1_EN, tmu->base + reg);
97 }
98 
99 static int imx91_tmu_to_mcelsius(int x)
100 {
101 	return x * MILLIDEGREE_PER_DEGREE / IMX91_TMP_FRAC;
102 }
103 
104 static int imx91_tmu_from_mcelsius(int x)
105 {
106 	return x * IMX91_TMP_FRAC / MILLIDEGREE_PER_DEGREE;
107 }
108 
109 static int imx91_tmu_get_temp(struct thermal_zone_device *tz, int *temp)
110 {
111 	struct imx91_tmu *tmu = thermal_zone_device_priv(tz);
112 	s16 data;
113 
114 	/* DATA0 is 16bit signed number */
115 	data = readw_relaxed(tmu->base + IMX91_TMU_DATA0);
116 	*temp = imx91_tmu_to_mcelsius(data);
117 
118 	return 0;
119 }
120 
121 static int imx91_tmu_set_trips(struct thermal_zone_device *tz, int low, int high)
122 {
123 	struct imx91_tmu *tmu = thermal_zone_device_priv(tz);
124 	int val;
125 
126 	if (high >= IMX91_TMU_TEMP_HIGH_LIMIT)
127 		return -EINVAL;
128 
129 	writel_relaxed(IMX91_TMU_CTRL0_THR1_IE, tmu->base + IMX91_TMU_CTRL0 + REG_CLR);
130 
131 	/* Comparator1 for temperature threshold */
132 	writel_relaxed(IMX91_TMU_THR_CTRL01_THR1_MASK, tmu->base + IMX91_TMU_THR_CTRL01 + REG_CLR);
133 	val = FIELD_PREP(IMX91_TMU_THR_CTRL01_THR1_MASK, imx91_tmu_from_mcelsius(high));
134 
135 	writel_relaxed(val, tmu->base + IMX91_TMU_THR_CTRL01 + REG_SET);
136 
137 	writel_relaxed(IMX91_TMU_STAT0_THR1_IF, tmu->base + IMX91_TMU_STAT0 + REG_CLR);
138 
139 	writel_relaxed(IMX91_TMU_CTRL0_THR1_IE, tmu->base + IMX91_TMU_CTRL0 + REG_SET);
140 
141 	return 0;
142 }
143 
144 static int imx91_init_from_nvmem_cells(struct imx91_tmu *tmu)
145 {
146 	struct device *dev = tmu->dev;
147 	u32 trim1, trim2;
148 	int ret;
149 
150 	ret = nvmem_cell_read_u32(dev, "trim1", &trim1);
151 	if (ret)
152 		return ret;
153 
154 	ret = nvmem_cell_read_u32(dev, "trim2", &trim2);
155 	if (ret)
156 		return ret;
157 
158 	if (trim1 == 0 || trim2 == 0)
159 		return -EINVAL;
160 
161 	writel_relaxed(trim1, tmu->base + IMX91_TMU_TRIM1);
162 	writel_relaxed(trim2, tmu->base + IMX91_TMU_TRIM2);
163 
164 	return 0;
165 }
166 
167 static void imx91_tmu_action_remove(void *data)
168 {
169 	struct imx91_tmu *tmu = data;
170 
171 	/* disable tmu */
172 	imx91_tmu_enable(tmu, false);
173 }
174 
175 static irqreturn_t imx91_tmu_alarm_irq(int irq, void *data)
176 {
177 	struct imx91_tmu *tmu = data;
178 	u32 val;
179 
180 	val = readl_relaxed(tmu->base + IMX91_TMU_STAT0);
181 
182 	/* Check if comparison interrupt occurred */
183 	if (val & IMX91_TMU_STAT0_THR1_IF) {
184 		/* Clear irq flag and disable interrupt until reconfigured */
185 		writel(IMX91_TMU_STAT0_THR1_IF, tmu->base + IMX91_TMU_STAT0 + REG_CLR);
186 		writel_relaxed(IMX91_TMU_CTRL0_THR1_IE, tmu->base + IMX91_TMU_CTRL0 + REG_CLR);
187 
188 		return IRQ_WAKE_THREAD;
189 	}
190 
191 	return IRQ_NONE;
192 }
193 
194 static irqreturn_t imx91_tmu_alarm_irq_thread(int irq, void *data)
195 {
196 	struct imx91_tmu *tmu = data;
197 
198 	thermal_zone_device_update(tmu->tzd, THERMAL_EVENT_UNSPECIFIED);
199 
200 	return IRQ_HANDLED;
201 }
202 
203 static int imx91_tmu_change_mode(struct thermal_zone_device *tz, enum thermal_device_mode mode)
204 {
205 	struct imx91_tmu *tmu = thermal_zone_device_priv(tz);
206 	int ret;
207 
208 	if (mode == THERMAL_DEVICE_ENABLED) {
209 		ret = pm_runtime_get(tmu->dev);
210 		if (ret < 0)
211 			return ret;
212 
213 		writel_relaxed(IMX91_TMU_CTRL0_THR1_IE | IMX91_TMU_CTRL0_THR1_MASK,
214 			       tmu->base + IMX91_TMU_CTRL0 + REG_CLR);
215 
216 		writel_relaxed(FIELD_PREP(IMX91_TMU_CTRL0_THR1_MASK, IMX91_TMU_THR_MODE_GE),
217 			       tmu->base + IMX91_TMU_CTRL0 + REG_SET);
218 		imx91_tmu_start(tmu, true);
219 	} else {
220 		writel_relaxed(IMX91_TMU_CTRL0_THR1_IE, tmu->base + IMX91_TMU_CTRL0 + REG_CLR);
221 		imx91_tmu_start(tmu, false);
222 		pm_runtime_put(tmu->dev);
223 	}
224 
225 	return 0;
226 }
227 
228 static struct thermal_zone_device_ops tmu_tz_ops = {
229 	.get_temp = imx91_tmu_get_temp,
230 	.change_mode = imx91_tmu_change_mode,
231 	.set_trips = imx91_tmu_set_trips,
232 };
233 
234 static int imx91_tmu_probe(struct platform_device *pdev)
235 {
236 	struct device *dev = &pdev->dev;
237 	struct imx91_tmu *tmu;
238 	unsigned long rate;
239 	int irq, ret;
240 	u32 div;
241 
242 	tmu = devm_kzalloc(dev, sizeof(struct imx91_tmu), GFP_KERNEL);
243 	if (!tmu)
244 		return -ENOMEM;
245 
246 	tmu->dev = dev;
247 
248 	tmu->base = devm_platform_ioremap_resource(pdev, 0);
249 	if (IS_ERR(tmu->base))
250 		return dev_err_probe(dev, PTR_ERR(tmu->base), "failed to get io resource");
251 
252 	tmu->clk = devm_clk_get_enabled(dev, NULL);
253 	if (IS_ERR(tmu->clk))
254 		return dev_err_probe(dev, PTR_ERR(tmu->clk), "failed to get tmu clock\n");
255 
256 	platform_set_drvdata(pdev, tmu);
257 
258 	/* disable the monitor during initialization */
259 	imx91_tmu_enable(tmu, false);
260 	imx91_tmu_start(tmu, false);
261 
262 	ret = imx91_init_from_nvmem_cells(tmu);
263 	if (ret) {
264 		dev_warn(dev, "can't get trim value, use default settings\n");
265 
266 		writel_relaxed(IMX91_TMU_DEFAULT_TRIM1_CONFIG, tmu->base + IMX91_TMU_TRIM1);
267 		writel_relaxed(IMX91_TMU_DEFAULT_TRIM2_CONFIG, tmu->base + IMX91_TMU_TRIM2);
268 	}
269 
270 	/* The typical conv clk is 4MHz, the output freq is 'rate / (div + 1)' */
271 	rate = clk_get_rate(tmu->clk);
272 	div = (rate / (4 * HZ_PER_MHZ)) - 1;
273 	if (div > IMX91_TMU_DIV_MAX)
274 		return dev_err_probe(dev, -EINVAL, "clock divider exceed hardware limitation");
275 
276 	/* Set divider value and enable divider */
277 	writel_relaxed(IMX91_TMU_DIV_EN | FIELD_PREP(IMX91_TMU_DIV_MASK, div),
278 		       tmu->base + IMX91_TMU_REF_DIV);
279 
280 	/* Set max power up delay: 'Tpud(ms) = 0xFF * 1000 / 4000000' */
281 	writel_relaxed(FIELD_PREP(IMX91_TMU_PUDL_MASK, 100U), tmu->base + IMX91_TMU_PUD_ST_CTRL);
282 
283 	/*
284 	 * Set resolution mode
285 	 * 00b - Conversion time = 0.59325 ms
286 	 * 01b - Conversion time = 1.10525 ms
287 	 * 10b - Conversion time = 2.12925 ms
288 	 * 11b - Conversion time = 4.17725 ms
289 	 */
290 	writel_relaxed(FIELD_PREP(IMX91_TMU_CTRL1_RES_MASK, 0x3),
291 		       tmu->base + IMX91_TMU_CTRL1 + REG_CLR);
292 	writel_relaxed(FIELD_PREP(IMX91_TMU_CTRL1_RES_MASK, 0x1),
293 		       tmu->base + IMX91_TMU_CTRL1 + REG_SET);
294 
295 	writel_relaxed(IMX91_TMU_CTRL1_MEAS_MODE_MASK, tmu->base + IMX91_TMU_CTRL1 + REG_CLR);
296 	writel_relaxed(FIELD_PREP(IMX91_TMU_CTRL1_MEAS_MODE_MASK,
297 				  IMX91_TMU_CTRL1_MEAS_MODE_PERIODIC),
298 		       tmu->base + IMX91_TMU_CTRL1 + REG_SET);
299 
300 	/*
301 	 * Set Periodic Measurement Frequency to 25Hz:
302 	 * tMEAS_FREQ = tCONV_CLK * PERIOD_CTRL[MEAS_FREQ]
303 	 */
304 	writel_relaxed(FIELD_PREP(IMX91_TMU_PERIOD_CTRL_MEAS_MASK, 4 * HZ_PER_MHZ / 25),
305 		       tmu->base + IMX91_TMU_PERIOD_CTRL);
306 
307 	imx91_tmu_enable(tmu, true);
308 	ret = devm_add_action(dev, imx91_tmu_action_remove, tmu);
309 	if (ret)
310 		return dev_err_probe(dev, ret, "Failure to add action imx91_tmu_action_remove()\n");
311 
312 	pm_runtime_set_active(dev);
313 	pm_runtime_get_noresume(dev);
314 	ret = devm_pm_runtime_enable(dev);
315 	if (ret)
316 		return ret;
317 
318 	tmu->tzd = devm_thermal_of_zone_register(dev, 0, tmu, &tmu_tz_ops);
319 	if (IS_ERR(tmu->tzd))
320 		return dev_err_probe(dev, PTR_ERR(tmu->tzd),
321 				     "failed to register thermal zone sensor\n");
322 
323 	devm_thermal_add_hwmon_sysfs(dev, tmu->tzd);
324 
325 	irq = platform_get_irq(pdev, 0);
326 	if (irq < 0)
327 		return irq;
328 
329 	ret = devm_request_threaded_irq(dev, irq, imx91_tmu_alarm_irq,
330 					imx91_tmu_alarm_irq_thread,
331 					IRQF_ONESHOT, "imx91_thermal", tmu);
332 
333 	if (ret < 0)
334 		return dev_err_probe(dev, ret, "failed to request alarm irq\n");
335 
336 	pm_runtime_put(dev);
337 
338 	return 0;
339 }
340 
341 static int imx91_tmu_runtime_suspend(struct device *dev)
342 {
343 	struct imx91_tmu *tmu = dev_get_drvdata(dev);
344 
345 	/* disable tmu */
346 	imx91_tmu_enable(tmu, false);
347 
348 	clk_disable_unprepare(tmu->clk);
349 
350 	return 0;
351 }
352 
353 static int imx91_tmu_runtime_resume(struct device *dev)
354 {
355 	struct imx91_tmu *tmu = dev_get_drvdata(dev);
356 	int ret;
357 
358 	ret = clk_prepare_enable(tmu->clk);
359 	if (ret)
360 		return ret;
361 
362 	imx91_tmu_enable(tmu, true);
363 
364 	return 0;
365 }
366 
367 static DEFINE_RUNTIME_DEV_PM_OPS(imx91_tmu_pm_ops, imx91_tmu_runtime_suspend,
368 				 imx91_tmu_runtime_resume, NULL);
369 
370 static const struct of_device_id imx91_tmu_table[] = {
371 	{ .compatible = "fsl,imx91-tmu", },
372 	{ },
373 };
374 MODULE_DEVICE_TABLE(of, imx91_tmu_table);
375 
376 static struct platform_driver imx91_tmu = {
377 	.driver = {
378 		.name	= "imx91_thermal",
379 		.pm	= pm_ptr(&imx91_tmu_pm_ops),
380 		.of_match_table = imx91_tmu_table,
381 	},
382 	.probe = imx91_tmu_probe,
383 };
384 module_platform_driver(imx91_tmu);
385 
386 MODULE_AUTHOR("Peng Fan <peng.fan@nxp.com>");
387 MODULE_DESCRIPTION("i.MX91 Thermal Monitor Unit driver");
388 MODULE_LICENSE("GPL");
389