1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2019 Samsung Electronics Co., Ltd.
4  *	      http://www.samsung.com/
5  * Copyright (c) 2020 Krzysztof Kozlowski <krzk@kernel.org>
6  *
7  * Exynos - CHIP ID support
8  * Author: Pankaj Dubey <pankaj.dubey@samsung.com>
9  * Author: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
10  * Author: Krzysztof Kozlowski <krzk@kernel.org>
11  *
12  * Samsung Exynos SoC Adaptive Supply Voltage and Chip ID support
13  */
14 
15 #include <linux/device.h>
16 #include <linux/errno.h>
17 #include <linux/mfd/syscon.h>
18 #include <linux/module.h>
19 #include <linux/of.h>
20 #include <linux/of_device.h>
21 #include <linux/platform_device.h>
22 #include <linux/regmap.h>
23 #include <linux/slab.h>
24 #include <linux/soc/samsung/exynos-chipid.h>
25 #include <linux/sys_soc.h>
26 
27 #include "exynos-asv.h"
28 
29 struct exynos_chipid_variant {
30 	unsigned int rev_reg;		/* revision register offset */
31 	unsigned int main_rev_shift;	/* main revision offset in rev_reg */
32 	unsigned int sub_rev_shift;	/* sub revision offset in rev_reg */
33 };
34 
35 struct exynos_chipid_info {
36 	u32 product_id;
37 	u32 revision;
38 };
39 
40 static const struct exynos_soc_id {
41 	const char *name;
42 	unsigned int id;
43 } soc_ids[] = {
44 	/* List ordered by SoC name */
45 	{ "EXYNOS3250", 0xE3472000 },
46 	{ "EXYNOS4210", 0x43200000 },	/* EVT0 revision */
47 	{ "EXYNOS4210", 0x43210000 },
48 	{ "EXYNOS4212", 0x43220000 },
49 	{ "EXYNOS4412", 0xE4412000 },
50 	{ "EXYNOS5250", 0x43520000 },
51 	{ "EXYNOS5260", 0xE5260000 },
52 	{ "EXYNOS5410", 0xE5410000 },
53 	{ "EXYNOS5420", 0xE5420000 },
54 	{ "EXYNOS5433", 0xE5433000 },
55 	{ "EXYNOS5440", 0xE5440000 },
56 	{ "EXYNOS5800", 0xE5422000 },
57 	{ "EXYNOS7420", 0xE7420000 },
58 	{ "EXYNOS850", 0xE3830000 },
59 	{ "EXYNOSAUTOV9", 0xAAA80000 },
60 };
61 
product_id_to_soc_id(unsigned int product_id)62 static const char *product_id_to_soc_id(unsigned int product_id)
63 {
64 	int i;
65 
66 	for (i = 0; i < ARRAY_SIZE(soc_ids); i++)
67 		if (product_id == soc_ids[i].id)
68 			return soc_ids[i].name;
69 	return NULL;
70 }
71 
exynos_chipid_get_chipid_info(struct regmap * regmap,const struct exynos_chipid_variant * data,struct exynos_chipid_info * soc_info)72 static int exynos_chipid_get_chipid_info(struct regmap *regmap,
73 		const struct exynos_chipid_variant *data,
74 		struct exynos_chipid_info *soc_info)
75 {
76 	int ret;
77 	unsigned int val, main_rev, sub_rev;
78 
79 	ret = regmap_read(regmap, EXYNOS_CHIPID_REG_PRO_ID, &val);
80 	if (ret < 0)
81 		return ret;
82 	soc_info->product_id = val & EXYNOS_MASK;
83 
84 	if (data->rev_reg != EXYNOS_CHIPID_REG_PRO_ID) {
85 		ret = regmap_read(regmap, data->rev_reg, &val);
86 		if (ret < 0)
87 			return ret;
88 	}
89 	main_rev = (val >> data->main_rev_shift) & EXYNOS_REV_PART_MASK;
90 	sub_rev = (val >> data->sub_rev_shift) & EXYNOS_REV_PART_MASK;
91 	soc_info->revision = (main_rev << EXYNOS_REV_PART_SHIFT) | sub_rev;
92 
93 	return 0;
94 }
95 
exynos_chipid_probe(struct platform_device * pdev)96 static int exynos_chipid_probe(struct platform_device *pdev)
97 {
98 	const struct exynos_chipid_variant *drv_data;
99 	struct exynos_chipid_info soc_info;
100 	struct soc_device_attribute *soc_dev_attr;
101 	struct soc_device *soc_dev;
102 	struct device_node *root;
103 	struct regmap *regmap;
104 	int ret;
105 
106 	drv_data = of_device_get_match_data(&pdev->dev);
107 	if (!drv_data)
108 		return -EINVAL;
109 
110 	regmap = device_node_to_regmap(pdev->dev.of_node);
111 	if (IS_ERR(regmap))
112 		return PTR_ERR(regmap);
113 
114 	ret = exynos_chipid_get_chipid_info(regmap, drv_data, &soc_info);
115 	if (ret < 0)
116 		return ret;
117 
118 	soc_dev_attr = devm_kzalloc(&pdev->dev, sizeof(*soc_dev_attr),
119 				    GFP_KERNEL);
120 	if (!soc_dev_attr)
121 		return -ENOMEM;
122 
123 	soc_dev_attr->family = "Samsung Exynos";
124 
125 	root = of_find_node_by_path("/");
126 	of_property_read_string(root, "model", &soc_dev_attr->machine);
127 	of_node_put(root);
128 
129 	soc_dev_attr->revision = devm_kasprintf(&pdev->dev, GFP_KERNEL,
130 						"%x", soc_info.revision);
131 	soc_dev_attr->soc_id = product_id_to_soc_id(soc_info.product_id);
132 	if (!soc_dev_attr->soc_id) {
133 		pr_err("Unknown SoC\n");
134 		return -ENODEV;
135 	}
136 
137 	/* please note that the actual registration will be deferred */
138 	soc_dev = soc_device_register(soc_dev_attr);
139 	if (IS_ERR(soc_dev))
140 		return PTR_ERR(soc_dev);
141 
142 	ret = exynos_asv_init(&pdev->dev, regmap);
143 	if (ret)
144 		goto err;
145 
146 	platform_set_drvdata(pdev, soc_dev);
147 
148 	dev_info(&pdev->dev, "Exynos: CPU[%s] PRO_ID[0x%x] REV[0x%x] Detected\n",
149 		 soc_dev_attr->soc_id, soc_info.product_id, soc_info.revision);
150 
151 	return 0;
152 
153 err:
154 	soc_device_unregister(soc_dev);
155 
156 	return ret;
157 }
158 
exynos_chipid_remove(struct platform_device * pdev)159 static int exynos_chipid_remove(struct platform_device *pdev)
160 {
161 	struct soc_device *soc_dev = platform_get_drvdata(pdev);
162 
163 	soc_device_unregister(soc_dev);
164 
165 	return 0;
166 }
167 
168 static const struct exynos_chipid_variant exynos4210_chipid_drv_data = {
169 	.rev_reg	= 0x0,
170 	.main_rev_shift	= 4,
171 	.sub_rev_shift	= 0,
172 };
173 
174 static const struct exynos_chipid_variant exynos850_chipid_drv_data = {
175 	.rev_reg	= 0x10,
176 	.main_rev_shift	= 20,
177 	.sub_rev_shift	= 16,
178 };
179 
180 static const struct of_device_id exynos_chipid_of_device_ids[] = {
181 	{
182 		.compatible	= "samsung,exynos4210-chipid",
183 		.data		= &exynos4210_chipid_drv_data,
184 	}, {
185 		.compatible	= "samsung,exynos850-chipid",
186 		.data		= &exynos850_chipid_drv_data,
187 	},
188 	{ }
189 };
190 MODULE_DEVICE_TABLE(of, exynos_chipid_of_device_ids);
191 
192 static struct platform_driver exynos_chipid_driver = {
193 	.driver = {
194 		.name = "exynos-chipid",
195 		.of_match_table = exynos_chipid_of_device_ids,
196 	},
197 	.probe	= exynos_chipid_probe,
198 	.remove	= exynos_chipid_remove,
199 };
200 module_platform_driver(exynos_chipid_driver);
201 
202 MODULE_DESCRIPTION("Samsung Exynos ChipID controller and ASV driver");
203 MODULE_AUTHOR("Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>");
204 MODULE_AUTHOR("Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>");
205 MODULE_AUTHOR("Pankaj Dubey <pankaj.dubey@samsung.com>");
206 MODULE_AUTHOR("Sylwester Nawrocki <s.nawrocki@samsung.com>");
207 MODULE_LICENSE("GPL");
208