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