1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2014 Linaro Ltd.
4  *
5  * Author: Linus Walleij <linus.walleij@linaro.org>
6  */
7 #include <linux/init.h>
8 #include <linux/io.h>
9 #include <linux/slab.h>
10 #include <linux/sys_soc.h>
11 #include <linux/platform_device.h>
12 #include <linux/mfd/syscon.h>
13 #include <linux/regmap.h>
14 #include <linux/of.h>
15 
16 #define INTEGRATOR_HDR_ID_OFFSET	0x00
17 
18 static u32 integrator_coreid;
19 
20 static const struct of_device_id integrator_cm_match[] = {
21 	{ .compatible = "arm,core-module-integrator", },
22 	{ }
23 };
24 
25 static const char *integrator_arch_str(u32 id)
26 {
27 	switch ((id >> 16) & 0xff) {
28 	case 0x00:
29 		return "ASB little-endian";
30 	case 0x01:
31 		return "AHB little-endian";
32 	case 0x03:
33 		return "AHB-Lite system bus, bi-endian";
34 	case 0x04:
35 		return "AHB";
36 	case 0x08:
37 		return "AHB system bus, ASB processor bus";
38 	default:
39 		return "Unknown";
40 	}
41 }
42 
43 static const char *integrator_fpga_str(u32 id)
44 {
45 	switch ((id >> 12) & 0xf) {
46 	case 0x01:
47 		return "XC4062";
48 	case 0x02:
49 		return "XC4085";
50 	case 0x03:
51 		return "XVC600";
52 	case 0x04:
53 		return "EPM7256AE (Altera PLD)";
54 	default:
55 		return "Unknown";
56 	}
57 }
58 
59 static ssize_t
60 manufacturer_show(struct device *dev, struct device_attribute *attr, char *buf)
61 {
62 	return sprintf(buf, "%02x\n", integrator_coreid >> 24);
63 }
64 
65 static DEVICE_ATTR_RO(manufacturer);
66 
67 static ssize_t
68 arch_show(struct device *dev, struct device_attribute *attr, char *buf)
69 {
70 	return sprintf(buf, "%s\n", integrator_arch_str(integrator_coreid));
71 }
72 
73 static DEVICE_ATTR_RO(arch);
74 
75 static ssize_t
76 fpga_show(struct device *dev, struct device_attribute *attr, char *buf)
77 {
78 	return sprintf(buf, "%s\n", integrator_fpga_str(integrator_coreid));
79 }
80 
81 static DEVICE_ATTR_RO(fpga);
82 
83 static ssize_t
84 build_show(struct device *dev, struct device_attribute *attr, char *buf)
85 {
86 	return sprintf(buf, "%02x\n", (integrator_coreid >> 4) & 0xFF);
87 }
88 
89 static DEVICE_ATTR_RO(build);
90 
91 static struct attribute *integrator_attrs[] = {
92 	&dev_attr_manufacturer.attr,
93 	&dev_attr_arch.attr,
94 	&dev_attr_fpga.attr,
95 	&dev_attr_build.attr,
96 	NULL
97 };
98 
99 ATTRIBUTE_GROUPS(integrator);
100 
101 static int __init integrator_soc_init(void)
102 {
103 	struct regmap *syscon_regmap;
104 	struct soc_device *soc_dev;
105 	struct soc_device_attribute *soc_dev_attr;
106 	struct device_node *np;
107 	struct device *dev;
108 	u32 val;
109 	int ret;
110 
111 	np = of_find_matching_node(NULL, integrator_cm_match);
112 	if (!np)
113 		return -ENODEV;
114 
115 	syscon_regmap = syscon_node_to_regmap(np);
116 	of_node_put(np);
117 	if (IS_ERR(syscon_regmap))
118 		return PTR_ERR(syscon_regmap);
119 
120 	ret = regmap_read(syscon_regmap, INTEGRATOR_HDR_ID_OFFSET,
121 			  &val);
122 	if (ret)
123 		return -ENODEV;
124 	integrator_coreid = val;
125 
126 	soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
127 	if (!soc_dev_attr)
128 		return -ENOMEM;
129 
130 	soc_dev_attr->soc_id = "Integrator";
131 	soc_dev_attr->machine = "Integrator";
132 	soc_dev_attr->family = "Versatile";
133 	soc_dev_attr->custom_attr_group = integrator_groups[0];
134 	soc_dev = soc_device_register(soc_dev_attr);
135 	if (IS_ERR(soc_dev)) {
136 		kfree(soc_dev_attr);
137 		return -ENODEV;
138 	}
139 	dev = soc_device_to_device(soc_dev);
140 
141 	dev_info(dev, "Detected ARM core module:\n");
142 	dev_info(dev, "    Manufacturer: %02x\n", (val >> 24));
143 	dev_info(dev, "    Architecture: %s\n", integrator_arch_str(val));
144 	dev_info(dev, "    FPGA: %s\n", integrator_fpga_str(val));
145 	dev_info(dev, "    Build: %02x\n", (val >> 4) & 0xFF);
146 	dev_info(dev, "    Rev: %c\n", ('A' + (val & 0x03)));
147 
148 	return 0;
149 }
150 device_initcall(integrator_soc_init);
151