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/* System ID in syscon */
21#define REALVIEW_SYS_ID_OFFSET 0x00
22
23static const struct of_device_id realview_soc_of_match[] = {
24	{ .compatible = "arm,realview-eb-soc",	},
25	{ .compatible = "arm,realview-pb1176-soc", },
26	{ .compatible = "arm,realview-pb11mp-soc", },
27	{ .compatible = "arm,realview-pba8-soc", },
28	{ .compatible = "arm,realview-pbx-soc", },
29	{ }
30};
31
32static u32 realview_coreid;
33
34static const char *realview_board_str(u32 id)
35{
36	switch ((id >> 16) & 0xfff) {
37	case 0x0147:
38		return "HBI-0147";
39	default:
40		return "Unknown";
41	}
42}
43
44static const char *realview_arch_str(u32 id)
45{
46	switch ((id >> 8) & 0xf) {
47	case 0x05:
48		return "Multi-layer AXI";
49	default:
50		return "Unknown";
51	}
52}
53
54static ssize_t realview_get_manf(struct device *dev,
55			      struct device_attribute *attr,
56			      char *buf)
57{
58	return sprintf(buf, "%02x\n", realview_coreid >> 24);
59}
60
61static struct device_attribute realview_manf_attr =
62	__ATTR(manufacturer,  S_IRUGO, realview_get_manf,  NULL);
63
64static ssize_t realview_get_board(struct device *dev,
65			      struct device_attribute *attr,
66			      char *buf)
67{
68	return sprintf(buf, "%s\n", realview_board_str(realview_coreid));
69}
70
71static struct device_attribute realview_board_attr =
72	__ATTR(board,  S_IRUGO, realview_get_board,  NULL);
73
74static ssize_t realview_get_arch(struct device *dev,
75			      struct device_attribute *attr,
76			      char *buf)
77{
78	return sprintf(buf, "%s\n", realview_arch_str(realview_coreid));
79}
80
81static struct device_attribute realview_arch_attr =
82	__ATTR(fpga,  S_IRUGO, realview_get_arch,  NULL);
83
84static ssize_t realview_get_build(struct device *dev,
85			       struct device_attribute *attr,
86			       char *buf)
87{
88	return sprintf(buf, "%02x\n", (realview_coreid & 0xFF));
89}
90
91static struct device_attribute realview_build_attr =
92	__ATTR(build,  S_IRUGO, realview_get_build,  NULL);
93
94static int realview_soc_probe(struct platform_device *pdev)
95{
96	static struct regmap *syscon_regmap;
97	struct soc_device *soc_dev;
98	struct soc_device_attribute *soc_dev_attr;
99	struct device_node *np = pdev->dev.of_node;
100	int ret;
101
102	syscon_regmap = syscon_regmap_lookup_by_phandle(np, "regmap");
103	if (IS_ERR(syscon_regmap))
104		return PTR_ERR(syscon_regmap);
105
106	soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
107	if (!soc_dev_attr)
108		return -ENOMEM;
109
110	ret = of_property_read_string(np, "compatible",
111				      &soc_dev_attr->soc_id);
112	if (ret)
113		return -EINVAL;
114
115	soc_dev_attr->machine = "RealView";
116	soc_dev_attr->family = "Versatile";
117	soc_dev = soc_device_register(soc_dev_attr);
118	if (IS_ERR(soc_dev)) {
119		kfree(soc_dev_attr);
120		return -ENODEV;
121	}
122	ret = regmap_read(syscon_regmap, REALVIEW_SYS_ID_OFFSET,
123			  &realview_coreid);
124	if (ret)
125		return -ENODEV;
126
127	device_create_file(soc_device_to_device(soc_dev), &realview_manf_attr);
128	device_create_file(soc_device_to_device(soc_dev), &realview_board_attr);
129	device_create_file(soc_device_to_device(soc_dev), &realview_arch_attr);
130	device_create_file(soc_device_to_device(soc_dev), &realview_build_attr);
131
132	dev_info(&pdev->dev, "RealView Syscon Core ID: 0x%08x\n",
133		 realview_coreid);
134	/* FIXME: add attributes for SoC to sysfs */
135	return 0;
136}
137
138static struct platform_driver realview_soc_driver = {
139	.probe = realview_soc_probe,
140	.driver = {
141		.name = "realview-soc",
142		.of_match_table = realview_soc_of_match,
143	},
144};
145module_platform_driver(realview_soc_driver);
146