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