1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Amlogic Thermal Sensor Driver
4  *
5  * Copyright (C) 2017 Huan Biao <huan.biao@amlogic.com>
6  * Copyright (C) 2019 Guillaume La Roque <glaroque@baylibre.com>
7  *
8  * Register value to celsius temperature formulas:
9  *	Read_Val	    m * U
10  * U = ---------, Uptat = ---------
11  *	2^16		  1 + n * U
12  *
13  * Temperature = A * ( Uptat + u_efuse / 2^16 )- B
14  *
15  *  A B m n : calibration parameters
16  *  u_efuse : fused calibration value, it's a signed 16 bits value
17  */
18 
19 #include <linux/bitfield.h>
20 #include <linux/clk.h>
21 #include <linux/io.h>
22 #include <linux/mfd/syscon.h>
23 #include <linux/module.h>
24 #include <linux/of.h>
25 #include <linux/of_address.h>
26 #include <linux/of_device.h>
27 #include <linux/platform_device.h>
28 #include <linux/regmap.h>
29 #include <linux/thermal.h>
30 
31 #include "thermal_core.h"
32 #include "thermal_hwmon.h"
33 
34 #define TSENSOR_CFG_REG1			0x4
35 	#define TSENSOR_CFG_REG1_RSET_VBG	BIT(12)
36 	#define TSENSOR_CFG_REG1_RSET_ADC	BIT(11)
37 	#define TSENSOR_CFG_REG1_VCM_EN		BIT(10)
38 	#define TSENSOR_CFG_REG1_VBG_EN		BIT(9)
39 	#define TSENSOR_CFG_REG1_OUT_CTL	BIT(6)
40 	#define TSENSOR_CFG_REG1_FILTER_EN	BIT(5)
41 	#define TSENSOR_CFG_REG1_DEM_EN		BIT(3)
42 	#define TSENSOR_CFG_REG1_CH_SEL		GENMASK(1, 0)
43 	#define TSENSOR_CFG_REG1_ENABLE		\
44 		(TSENSOR_CFG_REG1_FILTER_EN |	\
45 		 TSENSOR_CFG_REG1_VCM_EN |	\
46 		 TSENSOR_CFG_REG1_VBG_EN |	\
47 		 TSENSOR_CFG_REG1_DEM_EN |	\
48 		 TSENSOR_CFG_REG1_CH_SEL)
49 
50 #define TSENSOR_STAT0			0x40
51 
52 #define TSENSOR_STAT9			0x64
53 
54 #define TSENSOR_READ_TEMP_MASK		GENMASK(15, 0)
55 #define TSENSOR_TEMP_MASK		GENMASK(11, 0)
56 
57 #define TSENSOR_TRIM_SIGN_MASK		BIT(15)
58 #define TSENSOR_TRIM_TEMP_MASK		GENMASK(14, 0)
59 #define TSENSOR_TRIM_VERSION_MASK	GENMASK(31, 24)
60 
61 #define TSENSOR_TRIM_VERSION(_version)	\
62 	FIELD_GET(TSENSOR_TRIM_VERSION_MASK, _version)
63 
64 #define TSENSOR_TRIM_CALIB_VALID_MASK	(GENMASK(3, 2) | BIT(7))
65 
66 #define TSENSOR_CALIB_OFFSET	1
67 #define TSENSOR_CALIB_SHIFT	4
68 
69 /**
70  * struct amlogic_thermal_soc_calib_data
71  * @A: calibration parameters
72  * @B: calibration parameters
73  * @m: calibration parameters
74  * @n: calibration parameters
75  *
76  * This structure is required for configuration of amlogic thermal driver.
77  */
78 struct amlogic_thermal_soc_calib_data {
79 	int A;
80 	int B;
81 	int m;
82 	int n;
83 };
84 
85 /**
86  * struct amlogic_thermal_data
87  * @u_efuse_off: register offset to read fused calibration value
88  * @calibration_parameters: calibration parameters structure pointer
89  * @regmap_config: regmap config for the device
90  * This structure is required for configuration of amlogic thermal driver.
91  */
92 struct amlogic_thermal_data {
93 	int u_efuse_off;
94 	const struct amlogic_thermal_soc_calib_data *calibration_parameters;
95 	const struct regmap_config *regmap_config;
96 };
97 
98 struct amlogic_thermal {
99 	struct platform_device *pdev;
100 	const struct amlogic_thermal_data *data;
101 	struct regmap *regmap;
102 	struct regmap *sec_ao_map;
103 	struct clk *clk;
104 	struct thermal_zone_device *tzd;
105 	u32 trim_info;
106 };
107 
108 /*
109  * Calculate a temperature value from a temperature code.
110  * The unit of the temperature is degree milliCelsius.
111  */
amlogic_thermal_code_to_millicelsius(struct amlogic_thermal * pdata,int temp_code)112 static int amlogic_thermal_code_to_millicelsius(struct amlogic_thermal *pdata,
113 						int temp_code)
114 {
115 	const struct amlogic_thermal_soc_calib_data *param =
116 					pdata->data->calibration_parameters;
117 	int temp;
118 	s64 factor, Uptat, uefuse;
119 
120 	uefuse = pdata->trim_info & TSENSOR_TRIM_SIGN_MASK ?
121 			     ~(pdata->trim_info & TSENSOR_TRIM_TEMP_MASK) + 1 :
122 			     (pdata->trim_info & TSENSOR_TRIM_TEMP_MASK);
123 
124 	factor = param->n * temp_code;
125 	factor = div_s64(factor, 100);
126 
127 	Uptat = temp_code * param->m;
128 	Uptat = div_s64(Uptat, 100);
129 	Uptat = Uptat * BIT(16);
130 	Uptat = div_s64(Uptat, BIT(16) + factor);
131 
132 	temp = (Uptat + uefuse) * param->A;
133 	temp = div_s64(temp, BIT(16));
134 	temp = (temp - param->B) * 100;
135 
136 	return temp;
137 }
138 
amlogic_thermal_initialize(struct amlogic_thermal * pdata)139 static int amlogic_thermal_initialize(struct amlogic_thermal *pdata)
140 {
141 	int ret = 0;
142 	int ver;
143 
144 	regmap_read(pdata->sec_ao_map, pdata->data->u_efuse_off,
145 		    &pdata->trim_info);
146 
147 	ver = TSENSOR_TRIM_VERSION(pdata->trim_info);
148 
149 	if ((ver & TSENSOR_TRIM_CALIB_VALID_MASK) == 0) {
150 		ret = -EINVAL;
151 		dev_err(&pdata->pdev->dev,
152 			"tsensor thermal calibration not supported: 0x%x!\n",
153 			ver);
154 	}
155 
156 	return ret;
157 }
158 
amlogic_thermal_enable(struct amlogic_thermal * data)159 static int amlogic_thermal_enable(struct amlogic_thermal *data)
160 {
161 	int ret;
162 
163 	ret = clk_prepare_enable(data->clk);
164 	if (ret)
165 		return ret;
166 
167 	regmap_update_bits(data->regmap, TSENSOR_CFG_REG1,
168 			   TSENSOR_CFG_REG1_ENABLE, TSENSOR_CFG_REG1_ENABLE);
169 
170 	return 0;
171 }
172 
amlogic_thermal_disable(struct amlogic_thermal * data)173 static int amlogic_thermal_disable(struct amlogic_thermal *data)
174 {
175 	regmap_update_bits(data->regmap, TSENSOR_CFG_REG1,
176 			   TSENSOR_CFG_REG1_ENABLE, 0);
177 	clk_disable_unprepare(data->clk);
178 
179 	return 0;
180 }
181 
amlogic_thermal_get_temp(struct thermal_zone_device * tz,int * temp)182 static int amlogic_thermal_get_temp(struct thermal_zone_device *tz, int *temp)
183 {
184 	unsigned int tval;
185 	struct amlogic_thermal *pdata = tz->devdata;
186 
187 	if (!pdata)
188 		return -EINVAL;
189 
190 	regmap_read(pdata->regmap, TSENSOR_STAT0, &tval);
191 	*temp =
192 	   amlogic_thermal_code_to_millicelsius(pdata,
193 						tval & TSENSOR_READ_TEMP_MASK);
194 
195 	return 0;
196 }
197 
198 static const struct thermal_zone_device_ops amlogic_thermal_ops = {
199 	.get_temp	= amlogic_thermal_get_temp,
200 };
201 
202 static const struct regmap_config amlogic_thermal_regmap_config_g12a = {
203 	.reg_bits = 8,
204 	.val_bits = 32,
205 	.reg_stride = 4,
206 	.max_register = TSENSOR_STAT9,
207 };
208 
209 static const struct amlogic_thermal_soc_calib_data amlogic_thermal_g12a = {
210 	.A = 9411,
211 	.B = 3159,
212 	.m = 424,
213 	.n = 324,
214 };
215 
216 static const struct amlogic_thermal_data amlogic_thermal_g12a_cpu_param = {
217 	.u_efuse_off = 0x128,
218 	.calibration_parameters = &amlogic_thermal_g12a,
219 	.regmap_config = &amlogic_thermal_regmap_config_g12a,
220 };
221 
222 static const struct amlogic_thermal_data amlogic_thermal_g12a_ddr_param = {
223 	.u_efuse_off = 0xf0,
224 	.calibration_parameters = &amlogic_thermal_g12a,
225 	.regmap_config = &amlogic_thermal_regmap_config_g12a,
226 };
227 
228 static const struct of_device_id of_amlogic_thermal_match[] = {
229 	{
230 		.compatible = "amlogic,g12a-ddr-thermal",
231 		.data = &amlogic_thermal_g12a_ddr_param,
232 	},
233 	{
234 		.compatible = "amlogic,g12a-cpu-thermal",
235 		.data = &amlogic_thermal_g12a_cpu_param,
236 	},
237 	{ /* sentinel */ }
238 };
239 MODULE_DEVICE_TABLE(of, of_amlogic_thermal_match);
240 
amlogic_thermal_probe(struct platform_device * pdev)241 static int amlogic_thermal_probe(struct platform_device *pdev)
242 {
243 	struct amlogic_thermal *pdata;
244 	struct device *dev = &pdev->dev;
245 	void __iomem *base;
246 	int ret;
247 
248 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
249 	if (!pdata)
250 		return -ENOMEM;
251 
252 	pdata->data = of_device_get_match_data(dev);
253 	pdata->pdev = pdev;
254 	platform_set_drvdata(pdev, pdata);
255 
256 	base = devm_platform_ioremap_resource(pdev, 0);
257 	if (IS_ERR(base))
258 		return PTR_ERR(base);
259 
260 	pdata->regmap = devm_regmap_init_mmio(dev, base,
261 					      pdata->data->regmap_config);
262 	if (IS_ERR(pdata->regmap))
263 		return PTR_ERR(pdata->regmap);
264 
265 	pdata->clk = devm_clk_get(dev, NULL);
266 	if (IS_ERR(pdata->clk)) {
267 		if (PTR_ERR(pdata->clk) != -EPROBE_DEFER)
268 			dev_err(dev, "failed to get clock\n");
269 		return PTR_ERR(pdata->clk);
270 	}
271 
272 	pdata->sec_ao_map = syscon_regmap_lookup_by_phandle
273 		(pdev->dev.of_node, "amlogic,ao-secure");
274 	if (IS_ERR(pdata->sec_ao_map)) {
275 		dev_err(dev, "syscon regmap lookup failed.\n");
276 		return PTR_ERR(pdata->sec_ao_map);
277 	}
278 
279 	pdata->tzd = devm_thermal_of_zone_register(&pdev->dev,
280 						   0,
281 						   pdata,
282 						   &amlogic_thermal_ops);
283 	if (IS_ERR(pdata->tzd)) {
284 		ret = PTR_ERR(pdata->tzd);
285 		dev_err(dev, "Failed to register tsensor: %d\n", ret);
286 		return ret;
287 	}
288 
289 	if (devm_thermal_add_hwmon_sysfs(pdata->tzd))
290 		dev_warn(&pdev->dev, "Failed to add hwmon sysfs attributes\n");
291 
292 	ret = amlogic_thermal_initialize(pdata);
293 	if (ret)
294 		return ret;
295 
296 	ret = amlogic_thermal_enable(pdata);
297 
298 	return ret;
299 }
300 
amlogic_thermal_remove(struct platform_device * pdev)301 static int amlogic_thermal_remove(struct platform_device *pdev)
302 {
303 	struct amlogic_thermal *data = platform_get_drvdata(pdev);
304 
305 	return amlogic_thermal_disable(data);
306 }
307 
amlogic_thermal_suspend(struct device * dev)308 static int __maybe_unused amlogic_thermal_suspend(struct device *dev)
309 {
310 	struct amlogic_thermal *data = dev_get_drvdata(dev);
311 
312 	return amlogic_thermal_disable(data);
313 }
314 
amlogic_thermal_resume(struct device * dev)315 static int __maybe_unused amlogic_thermal_resume(struct device *dev)
316 {
317 	struct amlogic_thermal *data = dev_get_drvdata(dev);
318 
319 	return amlogic_thermal_enable(data);
320 }
321 
322 static SIMPLE_DEV_PM_OPS(amlogic_thermal_pm_ops,
323 			 amlogic_thermal_suspend, amlogic_thermal_resume);
324 
325 static struct platform_driver amlogic_thermal_driver = {
326 	.driver = {
327 		.name		= "amlogic_thermal",
328 		.pm		= &amlogic_thermal_pm_ops,
329 		.of_match_table = of_amlogic_thermal_match,
330 	},
331 	.probe	= amlogic_thermal_probe,
332 	.remove	= amlogic_thermal_remove,
333 };
334 
335 module_platform_driver(amlogic_thermal_driver);
336 
337 MODULE_AUTHOR("Guillaume La Roque <glaroque@baylibre.com>");
338 MODULE_DESCRIPTION("Amlogic thermal driver");
339 MODULE_LICENSE("GPL v2");
340