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/of.h>
14 #include <linux/of_device.h>
15 #include <linux/platform_device.h>
16 #include <linux/thermal.h>
17 
18 #include "thermal_core.h"
19 
20 #define TER			0x0	/* TMU enable */
21 #define TPS			0x4
22 #define TRITSR			0x20	/* TMU immediate temp */
23 
24 #define TER_ADC_PD		BIT(30)
25 #define TER_EN			BIT(31)
26 #define TRITSR_TEMP0_VAL_MASK	0xff
27 #define TRITSR_TEMP1_VAL_MASK	0xff0000
28 
29 #define PROBE_SEL_ALL		GENMASK(31, 30)
30 
31 #define probe_status_offset(x)	(30 + x)
32 #define SIGN_BIT		BIT(7)
33 #define TEMP_VAL_MASK		GENMASK(6, 0)
34 
35 #define VER1_TEMP_LOW_LIMIT	10000
36 #define VER2_TEMP_LOW_LIMIT	-40000
37 #define VER2_TEMP_HIGH_LIMIT	125000
38 
39 #define TMU_VER1		0x1
40 #define TMU_VER2		0x2
41 
42 struct thermal_soc_data {
43 	u32 num_sensors;
44 	u32 version;
45 	int (*get_temp)(void *, int *);
46 };
47 
48 struct tmu_sensor {
49 	struct imx8mm_tmu *priv;
50 	u32 hw_id;
51 	struct thermal_zone_device *tzd;
52 };
53 
54 struct imx8mm_tmu {
55 	void __iomem *base;
56 	struct clk *clk;
57 	const struct thermal_soc_data *socdata;
58 	struct tmu_sensor sensors[];
59 };
60 
61 static int imx8mm_tmu_get_temp(void *data, int *temp)
62 {
63 	struct tmu_sensor *sensor = data;
64 	struct imx8mm_tmu *tmu = sensor->priv;
65 	u32 val;
66 
67 	val = readl_relaxed(tmu->base + TRITSR) & TRITSR_TEMP0_VAL_MASK;
68 	*temp = val * 1000;
69 	if (*temp < VER1_TEMP_LOW_LIMIT)
70 		return -EAGAIN;
71 
72 	return 0;
73 }
74 
75 static int imx8mp_tmu_get_temp(void *data, int *temp)
76 {
77 	struct tmu_sensor *sensor = data;
78 	struct imx8mm_tmu *tmu = sensor->priv;
79 	unsigned long val;
80 	bool ready;
81 
82 	val = readl_relaxed(tmu->base + TRITSR);
83 	ready = test_bit(probe_status_offset(sensor->hw_id), &val);
84 	if (!ready)
85 		return -EAGAIN;
86 
87 	val = sensor->hw_id ? FIELD_GET(TRITSR_TEMP1_VAL_MASK, val) :
88 	      FIELD_GET(TRITSR_TEMP0_VAL_MASK, val);
89 	if (val & SIGN_BIT) /* negative */
90 		val = (~(val & TEMP_VAL_MASK) + 1);
91 
92 	*temp = val * 1000;
93 	if (*temp < VER2_TEMP_LOW_LIMIT || *temp > VER2_TEMP_HIGH_LIMIT)
94 		return -EAGAIN;
95 
96 	return 0;
97 }
98 
99 static int tmu_get_temp(void *data, int *temp)
100 {
101 	struct tmu_sensor *sensor = data;
102 	struct imx8mm_tmu *tmu = sensor->priv;
103 
104 	return tmu->socdata->get_temp(data, temp);
105 }
106 
107 static struct thermal_zone_of_device_ops tmu_tz_ops = {
108 	.get_temp = tmu_get_temp,
109 };
110 
111 static void imx8mm_tmu_enable(struct imx8mm_tmu *tmu, bool enable)
112 {
113 	u32 val;
114 
115 	val = readl_relaxed(tmu->base + TER);
116 	val = enable ? (val | TER_EN) : (val & ~TER_EN);
117 	if (tmu->socdata->version == TMU_VER2)
118 		val = enable ? (val & ~TER_ADC_PD) : (val | TER_ADC_PD);
119 	writel_relaxed(val, tmu->base + TER);
120 }
121 
122 static void imx8mm_tmu_probe_sel_all(struct imx8mm_tmu *tmu)
123 {
124 	u32 val;
125 
126 	val = readl_relaxed(tmu->base + TPS);
127 	val |= PROBE_SEL_ALL;
128 	writel_relaxed(val, tmu->base + TPS);
129 }
130 
131 static int imx8mm_tmu_probe(struct platform_device *pdev)
132 {
133 	const struct thermal_soc_data *data;
134 	struct imx8mm_tmu *tmu;
135 	int ret;
136 	int i;
137 
138 	data = of_device_get_match_data(&pdev->dev);
139 
140 	tmu = devm_kzalloc(&pdev->dev, struct_size(tmu, sensors,
141 			   data->num_sensors), GFP_KERNEL);
142 	if (!tmu)
143 		return -ENOMEM;
144 
145 	tmu->socdata = data;
146 
147 	tmu->base = devm_platform_ioremap_resource(pdev, 0);
148 	if (IS_ERR(tmu->base))
149 		return PTR_ERR(tmu->base);
150 
151 	tmu->clk = devm_clk_get(&pdev->dev, NULL);
152 	if (IS_ERR(tmu->clk))
153 		return dev_err_probe(&pdev->dev, PTR_ERR(tmu->clk),
154 				     "failed to get tmu clock\n");
155 
156 	ret = clk_prepare_enable(tmu->clk);
157 	if (ret) {
158 		dev_err(&pdev->dev, "failed to enable tmu clock: %d\n", ret);
159 		return ret;
160 	}
161 
162 	/* disable the monitor during initialization */
163 	imx8mm_tmu_enable(tmu, false);
164 
165 	for (i = 0; i < data->num_sensors; i++) {
166 		tmu->sensors[i].priv = tmu;
167 		tmu->sensors[i].tzd =
168 			devm_thermal_zone_of_sensor_register(&pdev->dev, i,
169 							     &tmu->sensors[i],
170 							     &tmu_tz_ops);
171 		if (IS_ERR(tmu->sensors[i].tzd)) {
172 			ret = PTR_ERR(tmu->sensors[i].tzd);
173 			dev_err(&pdev->dev,
174 				"failed to register thermal zone sensor[%d]: %d\n",
175 				i, ret);
176 			goto disable_clk;
177 		}
178 		tmu->sensors[i].hw_id = i;
179 	}
180 
181 	platform_set_drvdata(pdev, tmu);
182 
183 	/* enable all the probes for V2 TMU */
184 	if (tmu->socdata->version == TMU_VER2)
185 		imx8mm_tmu_probe_sel_all(tmu);
186 
187 	/* enable the monitor */
188 	imx8mm_tmu_enable(tmu, true);
189 
190 	return 0;
191 
192 disable_clk:
193 	clk_disable_unprepare(tmu->clk);
194 	return ret;
195 }
196 
197 static int imx8mm_tmu_remove(struct platform_device *pdev)
198 {
199 	struct imx8mm_tmu *tmu = platform_get_drvdata(pdev);
200 
201 	/* disable TMU */
202 	imx8mm_tmu_enable(tmu, false);
203 
204 	clk_disable_unprepare(tmu->clk);
205 	platform_set_drvdata(pdev, NULL);
206 
207 	return 0;
208 }
209 
210 static struct thermal_soc_data imx8mm_tmu_data = {
211 	.num_sensors = 1,
212 	.version = TMU_VER1,
213 	.get_temp = imx8mm_tmu_get_temp,
214 };
215 
216 static struct thermal_soc_data imx8mp_tmu_data = {
217 	.num_sensors = 2,
218 	.version = TMU_VER2,
219 	.get_temp = imx8mp_tmu_get_temp,
220 };
221 
222 static const struct of_device_id imx8mm_tmu_table[] = {
223 	{ .compatible = "fsl,imx8mm-tmu", .data = &imx8mm_tmu_data, },
224 	{ .compatible = "fsl,imx8mp-tmu", .data = &imx8mp_tmu_data, },
225 	{ },
226 };
227 MODULE_DEVICE_TABLE(of, imx8mm_tmu_table);
228 
229 static struct platform_driver imx8mm_tmu = {
230 	.driver = {
231 		.name	= "i.mx8mm_thermal",
232 		.of_match_table = imx8mm_tmu_table,
233 	},
234 	.probe = imx8mm_tmu_probe,
235 	.remove = imx8mm_tmu_remove,
236 };
237 module_platform_driver(imx8mm_tmu);
238 
239 MODULE_AUTHOR("Anson Huang <Anson.Huang@nxp.com>");
240 MODULE_DESCRIPTION("i.MX8MM Thermal Monitor Unit driver");
241 MODULE_LICENSE("GPL v2");
242