1 /*
2  * Copyright (C) 2014 Linaro Ltd.
3  *
4  * Author: Linus Walleij <linus.walleij@linaro.org>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2, as
8  * published by the Free Software Foundation.
9  *
10  */
11 #include <linux/init.h>
12 #include <linux/io.h>
13 #include <linux/slab.h>
14 #include <linux/sys_soc.h>
15 #include <linux/platform_device.h>
16 #include <linux/mfd/syscon.h>
17 #include <linux/regmap.h>
18 #include <linux/of.h>
19 
20 #define INTEGRATOR_HDR_ID_OFFSET	0x00
21 
22 static u32 integrator_coreid;
23 
24 static const struct of_device_id integrator_cm_match[] = {
25 	{ .compatible = "arm,core-module-integrator", },
26 	{ }
27 };
28 
29 static const char *integrator_arch_str(u32 id)
30 {
31 	switch ((id >> 16) & 0xff) {
32 	case 0x00:
33 		return "ASB little-endian";
34 	case 0x01:
35 		return "AHB little-endian";
36 	case 0x03:
37 		return "AHB-Lite system bus, bi-endian";
38 	case 0x04:
39 		return "AHB";
40 	case 0x08:
41 		return "AHB system bus, ASB processor bus";
42 	default:
43 		return "Unknown";
44 	}
45 }
46 
47 static const char *integrator_fpga_str(u32 id)
48 {
49 	switch ((id >> 12) & 0xf) {
50 	case 0x01:
51 		return "XC4062";
52 	case 0x02:
53 		return "XC4085";
54 	case 0x03:
55 		return "XVC600";
56 	case 0x04:
57 		return "EPM7256AE (Altera PLD)";
58 	default:
59 		return "Unknown";
60 	}
61 }
62 
63 static ssize_t integrator_get_manf(struct device *dev,
64 			      struct device_attribute *attr,
65 			      char *buf)
66 {
67 	return sprintf(buf, "%02x\n", integrator_coreid >> 24);
68 }
69 
70 static struct device_attribute integrator_manf_attr =
71 	__ATTR(manufacturer,  S_IRUGO, integrator_get_manf,  NULL);
72 
73 static ssize_t integrator_get_arch(struct device *dev,
74 			      struct device_attribute *attr,
75 			      char *buf)
76 {
77 	return sprintf(buf, "%s\n", integrator_arch_str(integrator_coreid));
78 }
79 
80 static struct device_attribute integrator_arch_attr =
81 	__ATTR(arch,  S_IRUGO, integrator_get_arch,  NULL);
82 
83 static ssize_t integrator_get_fpga(struct device *dev,
84 			      struct device_attribute *attr,
85 			      char *buf)
86 {
87 	return sprintf(buf, "%s\n", integrator_fpga_str(integrator_coreid));
88 }
89 
90 static struct device_attribute integrator_fpga_attr =
91 	__ATTR(fpga,  S_IRUGO, integrator_get_fpga,  NULL);
92 
93 static ssize_t integrator_get_build(struct device *dev,
94 			       struct device_attribute *attr,
95 			       char *buf)
96 {
97 	return sprintf(buf, "%02x\n", (integrator_coreid >> 4) & 0xFF);
98 }
99 
100 static struct device_attribute integrator_build_attr =
101 	__ATTR(build,  S_IRUGO, integrator_get_build,  NULL);
102 
103 static int __init integrator_soc_init(void)
104 {
105 	static struct regmap *syscon_regmap;
106 	struct soc_device *soc_dev;
107 	struct soc_device_attribute *soc_dev_attr;
108 	struct device_node *np;
109 	struct device *dev;
110 	u32 val;
111 	int ret;
112 
113 	np = of_find_matching_node(NULL, integrator_cm_match);
114 	if (!np)
115 		return -ENODEV;
116 
117 	syscon_regmap = syscon_node_to_regmap(np);
118 	if (IS_ERR(syscon_regmap))
119 		return PTR_ERR(syscon_regmap);
120 
121 	ret = regmap_read(syscon_regmap, INTEGRATOR_HDR_ID_OFFSET,
122 			  &val);
123 	if (ret)
124 		return -ENODEV;
125 	integrator_coreid = val;
126 
127 	soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
128 	if (!soc_dev_attr)
129 		return -ENOMEM;
130 
131 	soc_dev_attr->soc_id = "Integrator";
132 	soc_dev_attr->machine = "Integrator";
133 	soc_dev_attr->family = "Versatile";
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 	device_create_file(dev, &integrator_manf_attr);
142 	device_create_file(dev, &integrator_arch_attr);
143 	device_create_file(dev, &integrator_fpga_attr);
144 	device_create_file(dev, &integrator_build_attr);
145 
146 	dev_info(dev, "Detected ARM core module:\n");
147 	dev_info(dev, "    Manufacturer: %02x\n", (val >> 24));
148 	dev_info(dev, "    Architecture: %s\n", integrator_arch_str(val));
149 	dev_info(dev, "    FPGA: %s\n", integrator_fpga_str(val));
150 	dev_info(dev, "    Build: %02x\n", (val >> 4) & 0xFF);
151 	dev_info(dev, "    Rev: %c\n", ('A' + (val & 0x03)));
152 
153 	return 0;
154 }
155 device_initcall(integrator_soc_init);
156