1 | // SPDX-License-Identifier: GPL-2.0+ |
2 | /* |
3 | * Author: Yinbo Zhu <zhuyinbo@loongson.cn> |
4 | * Copyright (C) 2022-2023 Loongson Technology Corporation Limited |
5 | */ |
6 | |
7 | #include <linux/io.h> |
8 | #include <linux/slab.h> |
9 | #include <linux/module.h> |
10 | #include <linux/of_fdt.h> |
11 | #include <linux/sys_soc.h> |
12 | #include <linux/of_address.h> |
13 | #include <linux/platform_device.h> |
14 | |
15 | static struct soc_device_attribute soc_dev_attr; |
16 | static struct soc_device *soc_dev; |
17 | |
18 | /* |
19 | * Global Utility Registers. |
20 | * |
21 | * Not all registers defined in this structure are available on all chips, so |
22 | * you are expected to know whether a given register actually exists on your |
23 | * chip before you access it. |
24 | * |
25 | * Also, some registers are similar on different chips but have slightly |
26 | * different names. In these cases, one name is chosen to avoid extraneous |
27 | * #ifdefs. |
28 | */ |
29 | struct scfg_guts { |
30 | u32 svr; /* Version Register */ |
31 | u8 res0[4]; |
32 | u16 feature; /* Feature Register */ |
33 | u32 vendor; /* Vendor Register */ |
34 | u8 res1[6]; |
35 | u32 id; |
36 | u8 res2[0x3ff8 - 0x18]; |
37 | u32 chip; |
38 | }; |
39 | |
40 | static struct guts { |
41 | struct scfg_guts __iomem *regs; |
42 | bool little_endian; |
43 | } *guts; |
44 | |
45 | struct loongson2_soc_die_attr { |
46 | char *die; |
47 | u32 svr; |
48 | u32 mask; |
49 | }; |
50 | |
51 | /* SoC die attribute definition for Loongson-2 platform */ |
52 | static const struct loongson2_soc_die_attr loongson2_soc_die[] = { |
53 | |
54 | /* |
55 | * LoongArch-based SoCs Loongson-2 Series |
56 | */ |
57 | |
58 | /* Die: 2k1000, SoC: 2k1000 */ |
59 | { .die = "2K1000" , |
60 | .svr = 0x00000013, |
61 | .mask = 0x000000ff, |
62 | }, |
63 | { }, |
64 | }; |
65 | |
66 | static const struct loongson2_soc_die_attr *loongson2_soc_die_match( |
67 | u32 svr, const struct loongson2_soc_die_attr *matches) |
68 | { |
69 | while (matches->svr) { |
70 | if (matches->svr == (svr & matches->mask)) |
71 | return matches; |
72 | matches++; |
73 | } |
74 | |
75 | return NULL; |
76 | } |
77 | |
78 | static u32 loongson2_guts_get_svr(void) |
79 | { |
80 | u32 svr = 0; |
81 | |
82 | if (!guts || !guts->regs) |
83 | return svr; |
84 | |
85 | if (guts->little_endian) |
86 | svr = ioread32(&guts->regs->svr); |
87 | else |
88 | svr = ioread32be(&guts->regs->svr); |
89 | |
90 | return svr; |
91 | } |
92 | |
93 | static int loongson2_guts_probe(struct platform_device *pdev) |
94 | { |
95 | struct device_node *root, *np = pdev->dev.of_node; |
96 | struct device *dev = &pdev->dev; |
97 | const struct loongson2_soc_die_attr *soc_die; |
98 | const char *machine; |
99 | u32 svr; |
100 | |
101 | /* Initialize guts */ |
102 | guts = devm_kzalloc(dev, size: sizeof(*guts), GFP_KERNEL); |
103 | if (!guts) |
104 | return -ENOMEM; |
105 | |
106 | guts->little_endian = of_property_read_bool(np, propname: "little-endian" ); |
107 | |
108 | guts->regs = devm_platform_ioremap_resource(pdev, index: 0); |
109 | if (IS_ERR(ptr: guts->regs)) |
110 | return PTR_ERR(ptr: guts->regs); |
111 | |
112 | /* Register soc device */ |
113 | root = of_find_node_by_path(path: "/" ); |
114 | if (of_property_read_string(np: root, propname: "model" , out_string: &machine)) |
115 | of_property_read_string_index(np: root, propname: "compatible" , index: 0, output: &machine); |
116 | of_node_put(node: root); |
117 | if (machine) |
118 | soc_dev_attr.machine = devm_kstrdup(dev, s: machine, GFP_KERNEL); |
119 | |
120 | svr = loongson2_guts_get_svr(); |
121 | soc_die = loongson2_soc_die_match(svr, matches: loongson2_soc_die); |
122 | if (soc_die) { |
123 | soc_dev_attr.family = devm_kasprintf(dev, GFP_KERNEL, |
124 | fmt: "Loongson %s" , soc_die->die); |
125 | } else { |
126 | soc_dev_attr.family = devm_kasprintf(dev, GFP_KERNEL, fmt: "Loongson" ); |
127 | } |
128 | if (!soc_dev_attr.family) |
129 | return -ENOMEM; |
130 | soc_dev_attr.soc_id = devm_kasprintf(dev, GFP_KERNEL, |
131 | fmt: "svr:0x%08x" , svr); |
132 | if (!soc_dev_attr.soc_id) |
133 | return -ENOMEM; |
134 | soc_dev_attr.revision = devm_kasprintf(dev, GFP_KERNEL, fmt: "%d.%d" , |
135 | (svr >> 4) & 0xf, svr & 0xf); |
136 | if (!soc_dev_attr.revision) |
137 | return -ENOMEM; |
138 | |
139 | soc_dev = soc_device_register(soc_plat_dev_attr: &soc_dev_attr); |
140 | if (IS_ERR(ptr: soc_dev)) |
141 | return PTR_ERR(ptr: soc_dev); |
142 | |
143 | pr_info("Machine: %s\n" , soc_dev_attr.machine); |
144 | pr_info("SoC family: %s\n" , soc_dev_attr.family); |
145 | pr_info("SoC ID: %s, Revision: %s\n" , |
146 | soc_dev_attr.soc_id, soc_dev_attr.revision); |
147 | |
148 | return 0; |
149 | } |
150 | |
151 | static void loongson2_guts_remove(struct platform_device *dev) |
152 | { |
153 | soc_device_unregister(soc_dev); |
154 | } |
155 | |
156 | /* |
157 | * Table for matching compatible strings, for device tree |
158 | * guts node, for Loongson-2 SoCs. |
159 | */ |
160 | static const struct of_device_id loongson2_guts_of_match[] = { |
161 | { .compatible = "loongson,ls2k-chipid" , }, |
162 | {} |
163 | }; |
164 | MODULE_DEVICE_TABLE(of, loongson2_guts_of_match); |
165 | |
166 | static struct platform_driver loongson2_guts_driver = { |
167 | .driver = { |
168 | .name = "loongson2-guts" , |
169 | .of_match_table = loongson2_guts_of_match, |
170 | }, |
171 | .probe = loongson2_guts_probe, |
172 | .remove_new = loongson2_guts_remove, |
173 | }; |
174 | |
175 | static int __init loongson2_guts_init(void) |
176 | { |
177 | return platform_driver_register(&loongson2_guts_driver); |
178 | } |
179 | core_initcall(loongson2_guts_init); |
180 | |
181 | static void __exit loongson2_guts_exit(void) |
182 | { |
183 | platform_driver_unregister(&loongson2_guts_driver); |
184 | } |
185 | module_exit(loongson2_guts_exit); |
186 | |
187 | MODULE_DESCRIPTION("Loongson2 GUTS driver" ); |
188 | MODULE_LICENSE("GPL" ); |
189 | |