summaryrefslogtreecommitdiff
path: root/drivers/soc/loongson/loongson2_guts.c
blob: bace4bc8e03b01a372fffd80a37a95a7244205db (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
// SPDX-License-Identifier: GPL-2.0+
/*
 * Author: Yinbo Zhu <zhuyinbo@loongson.cn>
 * Copyright (C) 2022-2023 Loongson Technology Corporation Limited
 */

#include <linux/io.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/of_fdt.h>
#include <linux/sys_soc.h>
#include <linux/of_address.h>
#include <linux/platform_device.h>

static struct soc_device_attribute soc_dev_attr;
static struct soc_device *soc_dev;

/*
 * Global Utility Registers.
 *
 * Not all registers defined in this structure are available on all chips, so
 * you are expected to know whether a given register actually exists on your
 * chip before you access it.
 *
 * Also, some registers are similar on different chips but have slightly
 * different names.  In these cases, one name is chosen to avoid extraneous
 * #ifdefs.
 */
struct scfg_guts {
	u32     svr;            /* Version Register */
	u8      res0[4];
	u16     feature;        /* Feature Register */
	u32     vendor;         /* Vendor Register */
	u8      res1[6];
	u32     id;
	u8      res2[0x3ff8 - 0x18];
	u32     chip;
};

static struct guts {
	struct scfg_guts __iomem *regs;
	bool little_endian;
} *guts;

struct loongson2_soc_die_attr {
	char	*die;
	u32	svr;
	u32	mask;
};

/* SoC die attribute definition for Loongson-2 platform */
static const struct loongson2_soc_die_attr loongson2_soc_die[] = {

	/*
	 * LoongArch-based SoCs Loongson-2 Series
	 */

	/* Die: 2k1000, SoC: 2k1000 */
	{ .die		= "2K1000",
	  .svr		= 0x00000013,
	  .mask		= 0x000000ff,
	},
	{ },
};

static const struct loongson2_soc_die_attr *loongson2_soc_die_match(
	u32 svr, const struct loongson2_soc_die_attr *matches)
{
	while (matches->svr) {
		if (matches->svr == (svr & matches->mask))
			return matches;
		matches++;
	};

	return NULL;
}

static u32 loongson2_guts_get_svr(void)
{
	u32 svr = 0;

	if (!guts || !guts->regs)
		return svr;

	if (guts->little_endian)
		svr = ioread32(&guts->regs->svr);
	else
		svr = ioread32be(&guts->regs->svr);

	return svr;
}

static int loongson2_guts_probe(struct platform_device *pdev)
{
	struct device_node *root, *np = pdev->dev.of_node;
	struct device *dev = &pdev->dev;
	struct resource *res;
	const struct loongson2_soc_die_attr *soc_die;
	const char *machine;
	u32 svr;

	/* Initialize guts */
	guts = devm_kzalloc(dev, sizeof(*guts), GFP_KERNEL);
	if (!guts)
		return -ENOMEM;

	guts->little_endian = of_property_read_bool(np, "little-endian");

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	guts->regs = ioremap(res->start, res->end - res->start + 1);
	if (IS_ERR(guts->regs))
		return PTR_ERR(guts->regs);

	/* Register soc device */
	root = of_find_node_by_path("/");
	if (of_property_read_string(root, "model", &machine))
		of_property_read_string_index(root, "compatible", 0, &machine);
	of_node_put(root);
	if (machine)
		soc_dev_attr.machine = devm_kstrdup(dev, machine, GFP_KERNEL);

	svr = loongson2_guts_get_svr();
	soc_die = loongson2_soc_die_match(svr, loongson2_soc_die);
	if (soc_die) {
		soc_dev_attr.family = devm_kasprintf(dev, GFP_KERNEL,
						     "Loongson %s", soc_die->die);
	} else {
		soc_dev_attr.family = devm_kasprintf(dev, GFP_KERNEL, "Loongson");
	}
	if (!soc_dev_attr.family)
		return -ENOMEM;
	soc_dev_attr.soc_id = devm_kasprintf(dev, GFP_KERNEL,
					     "svr:0x%08x", svr);
	if (!soc_dev_attr.soc_id)
		return -ENOMEM;
	soc_dev_attr.revision = devm_kasprintf(dev, GFP_KERNEL, "%d.%d",
					       (svr >>  4) & 0xf, svr & 0xf);
	if (!soc_dev_attr.revision)
		return -ENOMEM;

	soc_dev = soc_device_register(&soc_dev_attr);
	if (IS_ERR(soc_dev))
		return PTR_ERR(soc_dev);

	pr_info("Machine: %s\n", soc_dev_attr.machine);
	pr_info("SoC family: %s\n", soc_dev_attr.family);
	pr_info("SoC ID: %s, Revision: %s\n",
		soc_dev_attr.soc_id, soc_dev_attr.revision);

	return 0;
}

static int loongson2_guts_remove(struct platform_device *dev)
{
	soc_device_unregister(soc_dev);

	return 0;
}

/*
 * Table for matching compatible strings, for device tree
 * guts node, for Loongson-2 SoCs.
 */
static const struct of_device_id loongson2_guts_of_match[] = {
	{ .compatible = "loongson,ls2k-chipid", },
	{}
};
MODULE_DEVICE_TABLE(of, loongson2_guts_of_match);

static struct platform_driver loongson2_guts_driver = {
	.driver = {
		.name = "loongson2-guts",
		.of_match_table = loongson2_guts_of_match,
	},
	.probe = loongson2_guts_probe,
	.remove = loongson2_guts_remove,
};

static int __init loongson2_guts_init(void)
{
	return platform_driver_register(&loongson2_guts_driver);
}
core_initcall(loongson2_guts_init);

static void __exit loongson2_guts_exit(void)
{
	platform_driver_unregister(&loongson2_guts_driver);
}
module_exit(loongson2_guts_exit);

MODULE_DESCRIPTION("Loongson2 GUTS driver");
MODULE_LICENSE("GPL");