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