1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Author: zhanghongchen <zhanghongchen@loongson.cn>
4  *         Yinbo Zhu <zhuyinbo@loongson.cn>
5  * Copyright (C) 2022-2023 Loongson Technology Corporation Limited
6  */
7 
8 #include <linux/interrupt.h>
9 #include <linux/io.h>
10 #include <linux/minmax.h>
11 #include <linux/module.h>
12 #include <linux/of_device.h>
13 #include <linux/platform_device.h>
14 #include <linux/thermal.h>
15 #include <linux/units.h>
16 #include "thermal_hwmon.h"
17 
18 #define LOONGSON2_MAX_SENSOR_SEL_NUM			3
19 
20 #define LOONGSON2_THSENS_CTRL_HI_REG			0x0
21 #define LOONGSON2_THSENS_CTRL_LOW_REG			0x8
22 #define LOONGSON2_THSENS_STATUS_REG			0x10
23 #define LOONGSON2_THSENS_OUT_REG			0x14
24 
25 #define LOONGSON2_THSENS_INT_LO				BIT(0)
26 #define LOONGSON2_THSENS_INT_HIGH			BIT(1)
27 #define LOONGSON2_THSENS_OUT_MASK			0xFF
28 
29 struct loongson2_thermal_chip_data {
30 	unsigned int	thermal_sensor_sel;
31 };
32 
33 struct loongson2_thermal_data {
34 	void __iomem	*regs;
35 	const struct loongson2_thermal_chip_data *chip_data;
36 };
37 
38 static int loongson2_thermal_set(struct loongson2_thermal_data *data,
39 					int low, int high, bool enable)
40 {
41 	u64 reg_ctrl = 0;
42 	int reg_off = data->chip_data->thermal_sensor_sel * 2;
43 
44 	low = clamp(-40, low, high);
45 	high = clamp(125, low, high);
46 
47 	low += HECTO;
48 	high += HECTO;
49 
50 	reg_ctrl = low;
51 	reg_ctrl |= enable ? 0x100 : 0;
52 	writew(reg_ctrl, data->regs + LOONGSON2_THSENS_CTRL_LOW_REG + reg_off);
53 
54 	reg_ctrl = high;
55 	reg_ctrl |= enable ? 0x100 : 0;
56 	writew(reg_ctrl, data->regs + LOONGSON2_THSENS_CTRL_HI_REG + reg_off);
57 
58 	return 0;
59 }
60 
61 static int loongson2_thermal_get_temp(struct thermal_zone_device *tz, int *temp)
62 {
63 	u32 reg_val;
64 	struct loongson2_thermal_data *data = thermal_zone_device_priv(tz);
65 
66 	reg_val = readl(data->regs + LOONGSON2_THSENS_OUT_REG);
67 	*temp = ((reg_val & LOONGSON2_THSENS_OUT_MASK) - HECTO) * KILO;
68 
69 	return 0;
70 }
71 
72 static irqreturn_t loongson2_thermal_irq_thread(int irq, void *dev)
73 {
74 	struct thermal_zone_device *tzd = dev;
75 	struct loongson2_thermal_data *data = thermal_zone_device_priv(tzd);
76 
77 	writeb(LOONGSON2_THSENS_INT_LO | LOONGSON2_THSENS_INT_HIGH, data->regs +
78 		LOONGSON2_THSENS_STATUS_REG);
79 
80 	thermal_zone_device_update(tzd, THERMAL_EVENT_UNSPECIFIED);
81 
82 	return IRQ_HANDLED;
83 }
84 
85 static int loongson2_thermal_set_trips(struct thermal_zone_device *tz, int low, int high)
86 {
87 	struct loongson2_thermal_data *data = thermal_zone_device_priv(tz);
88 
89 	return loongson2_thermal_set(data, low/MILLI, high/MILLI, true);
90 }
91 
92 static const struct thermal_zone_device_ops loongson2_of_thermal_ops = {
93 	.get_temp = loongson2_thermal_get_temp,
94 	.set_trips = loongson2_thermal_set_trips,
95 };
96 
97 static int loongson2_thermal_probe(struct platform_device *pdev)
98 {
99 	struct device *dev = &pdev->dev;
100 	struct loongson2_thermal_data *data;
101 	struct thermal_zone_device *tzd;
102 	int ret, irq, i;
103 
104 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
105 	if (!data)
106 		return -ENOMEM;
107 
108 	data->chip_data = device_get_match_data(dev);
109 
110 	data->regs = devm_platform_ioremap_resource(pdev, 0);
111 	if (IS_ERR(data->regs))
112 		return PTR_ERR(data->regs);
113 
114 	irq = platform_get_irq(pdev, 0);
115 	if (irq < 0)
116 		return irq;
117 
118 	writeb(LOONGSON2_THSENS_INT_LO | LOONGSON2_THSENS_INT_HIGH, data->regs +
119 		LOONGSON2_THSENS_STATUS_REG);
120 
121 	loongson2_thermal_set(data, 0, 0, false);
122 
123 	for (i = 0; i <= LOONGSON2_MAX_SENSOR_SEL_NUM; i++) {
124 		tzd = devm_thermal_of_zone_register(dev, i, data,
125 			&loongson2_of_thermal_ops);
126 
127 		if (!IS_ERR(tzd))
128 			break;
129 
130 		if (PTR_ERR(tzd) != ENODEV)
131 			continue;
132 
133 		return dev_err_probe(dev, PTR_ERR(tzd), "failed to register");
134 	}
135 
136 	ret = devm_request_threaded_irq(dev, irq, NULL, loongson2_thermal_irq_thread,
137 			IRQF_ONESHOT, "loongson2_thermal", tzd);
138 	if (ret < 0)
139 		return dev_err_probe(dev, ret, "failed to request alarm irq\n");
140 
141 	devm_thermal_add_hwmon_sysfs(dev, tzd);
142 
143 	return 0;
144 }
145 
146 static const struct loongson2_thermal_chip_data loongson2_thermal_ls2k1000_data = {
147 	.thermal_sensor_sel = 0,
148 };
149 
150 static const struct of_device_id of_loongson2_thermal_match[] = {
151 	{
152 		.compatible = "loongson,ls2k1000-thermal",
153 		.data = &loongson2_thermal_ls2k1000_data,
154 	},
155 	{ /* end */ }
156 };
157 MODULE_DEVICE_TABLE(of, of_loongson2_thermal_match);
158 
159 static struct platform_driver loongson2_thermal_driver = {
160 	.driver = {
161 		.name		= "loongson2_thermal",
162 		.of_match_table = of_loongson2_thermal_match,
163 	},
164 	.probe	= loongson2_thermal_probe,
165 };
166 module_platform_driver(loongson2_thermal_driver);
167 
168 MODULE_DESCRIPTION("Loongson2 thermal driver");
169 MODULE_LICENSE("GPL");
170