1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright 2020 NXP.
4  *
5  * Author: Anson Huang <Anson.Huang@nxp.com>
6  */
7 
8 #include <linux/bitfield.h>
9 #include <linux/clk.h>
10 #include <linux/err.h>
11 #include <linux/io.h>
12 #include <linux/module.h>
13 #include <linux/nvmem-consumer.h>
14 #include <linux/of.h>
15 #include <linux/of_device.h>
16 #include <linux/platform_device.h>
17 #include <linux/slab.h>
18 #include <linux/thermal.h>
19 
20 #include "thermal_core.h"
21 #include "thermal_hwmon.h"
22 
23 #define TER			0x0	/* TMU enable */
24 #define TPS			0x4
25 #define TRITSR			0x20	/* TMU immediate temp */
26 /* TMU calibration data registers */
27 #define TASR			0x28
28 #define TASR_BUF_SLOPE_MASK	GENMASK(19, 16)
29 #define TASR_BUF_VREF_MASK	GENMASK(4, 0)	/* TMU_V1 */
30 #define TASR_BUF_VERF_SEL_MASK	GENMASK(1, 0)	/* TMU_V2 */
31 #define TCALIV(n)		(0x30 + ((n) * 4))
32 #define TCALIV_EN		BIT(31)
33 #define TCALIV_HR_MASK		GENMASK(23, 16)	/* TMU_V1 */
34 #define TCALIV_RT_MASK		GENMASK(7, 0)	/* TMU_V1 */
35 #define TCALIV_SNSR105C_MASK	GENMASK(27, 16)	/* TMU_V2 */
36 #define TCALIV_SNSR25C_MASK	GENMASK(11, 0)	/* TMU_V2 */
37 #define TRIM			0x3c
38 #define TRIM_BJT_CUR_MASK	GENMASK(23, 20)
39 #define TRIM_BGR_MASK		GENMASK(31, 28)
40 #define TRIM_VLSB_MASK		GENMASK(15, 12)
41 #define TRIM_EN_CH		BIT(7)
42 
43 #define TER_ADC_PD		BIT(30)
44 #define TER_EN			BIT(31)
45 #define TRITSR_TEMP0_VAL_MASK	GENMASK(7, 0)
46 #define TRITSR_TEMP1_VAL_MASK	GENMASK(23, 16)
47 
48 #define PROBE_SEL_ALL		GENMASK(31, 30)
49 
50 #define probe_status_offset(x)	(30 + x)
51 #define SIGN_BIT		BIT(7)
52 #define TEMP_VAL_MASK		GENMASK(6, 0)
53 
54 /* TMU OCOTP calibration data bitfields */
55 #define ANA0_EN			BIT(25)
56 #define ANA0_BUF_VREF_MASK	GENMASK(24, 20)
57 #define ANA0_BUF_SLOPE_MASK	GENMASK(19, 16)
58 #define ANA0_HR_MASK		GENMASK(15, 8)
59 #define ANA0_RT_MASK		GENMASK(7, 0)
60 #define TRIM2_VLSB_MASK		GENMASK(23, 20)
61 #define TRIM2_BGR_MASK		GENMASK(19, 16)
62 #define TRIM2_BJT_CUR_MASK	GENMASK(15, 12)
63 #define TRIM2_BUF_SLOP_SEL_MASK	GENMASK(11, 8)
64 #define TRIM2_BUF_VERF_SEL_MASK	GENMASK(7, 6)
65 #define TRIM3_TCA25_0_LSB_MASK	GENMASK(31, 28)
66 #define TRIM3_TCA40_0_MASK	GENMASK(27, 16)
67 #define TRIM4_TCA40_1_MASK	GENMASK(31, 20)
68 #define TRIM4_TCA105_0_MASK	GENMASK(19, 8)
69 #define TRIM4_TCA25_0_MSB_MASK	GENMASK(7, 0)
70 #define TRIM5_TCA105_1_MASK	GENMASK(23, 12)
71 #define TRIM5_TCA25_1_MASK	GENMASK(11, 0)
72 
73 #define VER1_TEMP_LOW_LIMIT	10000
74 #define VER2_TEMP_LOW_LIMIT	-40000
75 #define VER2_TEMP_HIGH_LIMIT	125000
76 
77 #define TMU_VER1		0x1
78 #define TMU_VER2		0x2
79 
80 struct thermal_soc_data {
81 	u32 num_sensors;
82 	u32 version;
83 	int (*get_temp)(void *, int *);
84 };
85 
86 struct tmu_sensor {
87 	struct imx8mm_tmu *priv;
88 	u32 hw_id;
89 	struct thermal_zone_device *tzd;
90 };
91 
92 struct imx8mm_tmu {
93 	void __iomem *base;
94 	struct clk *clk;
95 	const struct thermal_soc_data *socdata;
96 	struct tmu_sensor sensors[];
97 };
98 
99 static int imx8mm_tmu_get_temp(void *data, int *temp)
100 {
101 	struct tmu_sensor *sensor = data;
102 	struct imx8mm_tmu *tmu = sensor->priv;
103 	u32 val;
104 
105 	val = readl_relaxed(tmu->base + TRITSR) & TRITSR_TEMP0_VAL_MASK;
106 
107 	/*
108 	 * Do not validate against the V bit (bit 31) due to errata
109 	 * ERR051272: TMU: Bit 31 of registers TMU_TSCR/TMU_TRITSR/TMU_TRATSR invalid
110 	 */
111 
112 	*temp = val * 1000;
113 	if (*temp < VER1_TEMP_LOW_LIMIT || *temp > VER2_TEMP_HIGH_LIMIT)
114 		return -EAGAIN;
115 
116 	return 0;
117 }
118 
119 static int imx8mp_tmu_get_temp(void *data, int *temp)
120 {
121 	struct tmu_sensor *sensor = data;
122 	struct imx8mm_tmu *tmu = sensor->priv;
123 	unsigned long val;
124 	bool ready;
125 
126 	val = readl_relaxed(tmu->base + TRITSR);
127 	ready = test_bit(probe_status_offset(sensor->hw_id), &val);
128 	if (!ready)
129 		return -EAGAIN;
130 
131 	val = sensor->hw_id ? FIELD_GET(TRITSR_TEMP1_VAL_MASK, val) :
132 	      FIELD_GET(TRITSR_TEMP0_VAL_MASK, val);
133 	if (val & SIGN_BIT) /* negative */
134 		val = (~(val & TEMP_VAL_MASK) + 1);
135 
136 	*temp = val * 1000;
137 	if (*temp < VER2_TEMP_LOW_LIMIT || *temp > VER2_TEMP_HIGH_LIMIT)
138 		return -EAGAIN;
139 
140 	return 0;
141 }
142 
143 static int tmu_get_temp(struct thermal_zone_device *tz, int *temp)
144 {
145 	struct tmu_sensor *sensor = tz->devdata;
146 	struct imx8mm_tmu *tmu = sensor->priv;
147 
148 	return tmu->socdata->get_temp(sensor, temp);
149 }
150 
151 static const struct thermal_zone_device_ops tmu_tz_ops = {
152 	.get_temp = tmu_get_temp,
153 };
154 
155 static void imx8mm_tmu_enable(struct imx8mm_tmu *tmu, bool enable)
156 {
157 	u32 val;
158 
159 	val = readl_relaxed(tmu->base + TER);
160 	val = enable ? (val | TER_EN) : (val & ~TER_EN);
161 	if (tmu->socdata->version == TMU_VER2)
162 		val = enable ? (val & ~TER_ADC_PD) : (val | TER_ADC_PD);
163 	writel_relaxed(val, tmu->base + TER);
164 }
165 
166 static void imx8mm_tmu_probe_sel_all(struct imx8mm_tmu *tmu)
167 {
168 	u32 val;
169 
170 	val = readl_relaxed(tmu->base + TPS);
171 	val |= PROBE_SEL_ALL;
172 	writel_relaxed(val, tmu->base + TPS);
173 }
174 
175 static int imx8mm_tmu_probe_set_calib_v1(struct platform_device *pdev,
176 					 struct imx8mm_tmu *tmu)
177 {
178 	struct device *dev = &pdev->dev;
179 	u32 ana0;
180 	int ret;
181 
182 	ret = nvmem_cell_read_u32(&pdev->dev, "calib", &ana0);
183 	if (ret) {
184 		dev_warn(dev, "Failed to read OCOTP nvmem cell (%d).\n", ret);
185 		return ret;
186 	}
187 
188 	writel(FIELD_PREP(TASR_BUF_VREF_MASK,
189 			  FIELD_GET(ANA0_BUF_VREF_MASK, ana0)) |
190 	       FIELD_PREP(TASR_BUF_SLOPE_MASK,
191 			  FIELD_GET(ANA0_BUF_SLOPE_MASK, ana0)),
192 	       tmu->base + TASR);
193 
194 	writel(FIELD_PREP(TCALIV_RT_MASK, FIELD_GET(ANA0_RT_MASK, ana0)) |
195 	       FIELD_PREP(TCALIV_HR_MASK, FIELD_GET(ANA0_HR_MASK, ana0)) |
196 	       ((ana0 & ANA0_EN) ? TCALIV_EN : 0),
197 	       tmu->base + TCALIV(0));
198 
199 	return 0;
200 }
201 
202 static int imx8mm_tmu_probe_set_calib_v2(struct platform_device *pdev,
203 					 struct imx8mm_tmu *tmu)
204 {
205 	struct device *dev = &pdev->dev;
206 	struct nvmem_cell *cell;
207 	u32 trim[4] = { 0 };
208 	size_t len;
209 	void *buf;
210 
211 	cell = nvmem_cell_get(dev, "calib");
212 	if (IS_ERR(cell))
213 		return PTR_ERR(cell);
214 
215 	buf = nvmem_cell_read(cell, &len);
216 	nvmem_cell_put(cell);
217 
218 	if (IS_ERR(buf))
219 		return PTR_ERR(buf);
220 
221 	memcpy(trim, buf, min(len, sizeof(trim)));
222 	kfree(buf);
223 
224 	if (len != 16) {
225 		dev_err(dev,
226 			"OCOTP nvmem cell length is %zu, must be 16.\n", len);
227 		return -EINVAL;
228 	}
229 
230 	/* Blank sample hardware */
231 	if (!trim[0] && !trim[1] && !trim[2] && !trim[3]) {
232 		/* Use a default 25C binary codes */
233 		writel(FIELD_PREP(TCALIV_SNSR25C_MASK, 0x63c),
234 		       tmu->base + TCALIV(0));
235 		writel(FIELD_PREP(TCALIV_SNSR25C_MASK, 0x63c),
236 		       tmu->base + TCALIV(1));
237 		return 0;
238 	}
239 
240 	writel(FIELD_PREP(TASR_BUF_VERF_SEL_MASK,
241 			  FIELD_GET(TRIM2_BUF_VERF_SEL_MASK, trim[0])) |
242 	       FIELD_PREP(TASR_BUF_SLOPE_MASK,
243 			  FIELD_GET(TRIM2_BUF_SLOP_SEL_MASK, trim[0])),
244 	       tmu->base + TASR);
245 
246 	writel(FIELD_PREP(TRIM_BJT_CUR_MASK,
247 			  FIELD_GET(TRIM2_BJT_CUR_MASK, trim[0])) |
248 	       FIELD_PREP(TRIM_BGR_MASK, FIELD_GET(TRIM2_BGR_MASK, trim[0])) |
249 	       FIELD_PREP(TRIM_VLSB_MASK, FIELD_GET(TRIM2_VLSB_MASK, trim[0])) |
250 	       TRIM_EN_CH,
251 	       tmu->base + TRIM);
252 
253 	writel(FIELD_PREP(TCALIV_SNSR25C_MASK,
254 			  FIELD_GET(TRIM3_TCA25_0_LSB_MASK, trim[1]) |
255 			  (FIELD_GET(TRIM4_TCA25_0_MSB_MASK, trim[2]) << 4)) |
256 	       FIELD_PREP(TCALIV_SNSR105C_MASK,
257 			  FIELD_GET(TRIM4_TCA105_0_MASK, trim[2])),
258 	       tmu->base + TCALIV(0));
259 
260 	writel(FIELD_PREP(TCALIV_SNSR25C_MASK,
261 			  FIELD_GET(TRIM5_TCA25_1_MASK, trim[3])) |
262 	       FIELD_PREP(TCALIV_SNSR105C_MASK,
263 			  FIELD_GET(TRIM5_TCA105_1_MASK, trim[3])),
264 	       tmu->base + TCALIV(1));
265 
266 	writel(FIELD_PREP(TCALIV_SNSR25C_MASK,
267 			  FIELD_GET(TRIM3_TCA40_0_MASK, trim[1])) |
268 	       FIELD_PREP(TCALIV_SNSR105C_MASK,
269 			  FIELD_GET(TRIM4_TCA40_1_MASK, trim[2])),
270 	       tmu->base + TCALIV(2));
271 
272 	return 0;
273 }
274 
275 static int imx8mm_tmu_probe_set_calib(struct platform_device *pdev,
276 				      struct imx8mm_tmu *tmu)
277 {
278 	struct device *dev = &pdev->dev;
279 
280 	/*
281 	 * Lack of calibration data OCOTP reference is not considered
282 	 * fatal to retain compatibility with old DTs. It is however
283 	 * strongly recommended to update such old DTs to get correct
284 	 * temperature compensation values for each SoC.
285 	 */
286 	if (!of_find_property(pdev->dev.of_node, "nvmem-cells", NULL)) {
287 		dev_warn(dev,
288 			 "No OCOTP nvmem reference found, SoC-specific calibration not loaded. Please update your DT.\n");
289 		return 0;
290 	}
291 
292 	if (tmu->socdata->version == TMU_VER1)
293 		return imx8mm_tmu_probe_set_calib_v1(pdev, tmu);
294 
295 	return imx8mm_tmu_probe_set_calib_v2(pdev, tmu);
296 }
297 
298 static int imx8mm_tmu_probe(struct platform_device *pdev)
299 {
300 	const struct thermal_soc_data *data;
301 	struct imx8mm_tmu *tmu;
302 	int ret;
303 	int i;
304 
305 	data = of_device_get_match_data(&pdev->dev);
306 
307 	tmu = devm_kzalloc(&pdev->dev, struct_size(tmu, sensors,
308 			   data->num_sensors), GFP_KERNEL);
309 	if (!tmu)
310 		return -ENOMEM;
311 
312 	tmu->socdata = data;
313 
314 	tmu->base = devm_platform_ioremap_resource(pdev, 0);
315 	if (IS_ERR(tmu->base))
316 		return PTR_ERR(tmu->base);
317 
318 	tmu->clk = devm_clk_get(&pdev->dev, NULL);
319 	if (IS_ERR(tmu->clk))
320 		return dev_err_probe(&pdev->dev, PTR_ERR(tmu->clk),
321 				     "failed to get tmu clock\n");
322 
323 	ret = clk_prepare_enable(tmu->clk);
324 	if (ret) {
325 		dev_err(&pdev->dev, "failed to enable tmu clock: %d\n", ret);
326 		return ret;
327 	}
328 
329 	/* disable the monitor during initialization */
330 	imx8mm_tmu_enable(tmu, false);
331 
332 	for (i = 0; i < data->num_sensors; i++) {
333 		tmu->sensors[i].priv = tmu;
334 		tmu->sensors[i].tzd =
335 			devm_thermal_of_zone_register(&pdev->dev, i,
336 						      &tmu->sensors[i],
337 						      &tmu_tz_ops);
338 		if (IS_ERR(tmu->sensors[i].tzd)) {
339 			ret = PTR_ERR(tmu->sensors[i].tzd);
340 			dev_err(&pdev->dev,
341 				"failed to register thermal zone sensor[%d]: %d\n",
342 				i, ret);
343 			goto disable_clk;
344 		}
345 		tmu->sensors[i].hw_id = i;
346 
347 		if (devm_thermal_add_hwmon_sysfs(tmu->sensors[i].tzd))
348 			dev_warn(&pdev->dev, "failed to add hwmon sysfs attributes\n");
349 	}
350 
351 	platform_set_drvdata(pdev, tmu);
352 
353 	ret = imx8mm_tmu_probe_set_calib(pdev, tmu);
354 	if (ret)
355 		goto disable_clk;
356 
357 	/* enable all the probes for V2 TMU */
358 	if (tmu->socdata->version == TMU_VER2)
359 		imx8mm_tmu_probe_sel_all(tmu);
360 
361 	/* enable the monitor */
362 	imx8mm_tmu_enable(tmu, true);
363 
364 	return 0;
365 
366 disable_clk:
367 	clk_disable_unprepare(tmu->clk);
368 	return ret;
369 }
370 
371 static int imx8mm_tmu_remove(struct platform_device *pdev)
372 {
373 	struct imx8mm_tmu *tmu = platform_get_drvdata(pdev);
374 
375 	/* disable TMU */
376 	imx8mm_tmu_enable(tmu, false);
377 
378 	clk_disable_unprepare(tmu->clk);
379 	platform_set_drvdata(pdev, NULL);
380 
381 	return 0;
382 }
383 
384 static struct thermal_soc_data imx8mm_tmu_data = {
385 	.num_sensors = 1,
386 	.version = TMU_VER1,
387 	.get_temp = imx8mm_tmu_get_temp,
388 };
389 
390 static struct thermal_soc_data imx8mp_tmu_data = {
391 	.num_sensors = 2,
392 	.version = TMU_VER2,
393 	.get_temp = imx8mp_tmu_get_temp,
394 };
395 
396 static const struct of_device_id imx8mm_tmu_table[] = {
397 	{ .compatible = "fsl,imx8mm-tmu", .data = &imx8mm_tmu_data, },
398 	{ .compatible = "fsl,imx8mp-tmu", .data = &imx8mp_tmu_data, },
399 	{ },
400 };
401 MODULE_DEVICE_TABLE(of, imx8mm_tmu_table);
402 
403 static struct platform_driver imx8mm_tmu = {
404 	.driver = {
405 		.name	= "i.mx8mm_thermal",
406 		.of_match_table = imx8mm_tmu_table,
407 	},
408 	.probe = imx8mm_tmu_probe,
409 	.remove = imx8mm_tmu_remove,
410 };
411 module_platform_driver(imx8mm_tmu);
412 
413 MODULE_AUTHOR("Anson Huang <Anson.Huang@nxp.com>");
414 MODULE_DESCRIPTION("i.MX8MM Thermal Monitor Unit driver");
415 MODULE_LICENSE("GPL v2");
416