xref: /openbmc/linux/drivers/soc/ux500/ux500-soc-id.c (revision 55fd7e02)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) ST-Ericsson SA 2010
4  *
5  * Author: Rabin Vincent <rabin.vincent@stericsson.com> for ST-Ericsson
6  */
7 
8 #include <linux/kernel.h>
9 #include <linux/init.h>
10 #include <linux/io.h>
11 #include <linux/module.h>
12 #include <linux/random.h>
13 #include <linux/slab.h>
14 #include <linux/of.h>
15 #include <linux/of_address.h>
16 #include <linux/sys_soc.h>
17 
18 #include <asm/cputype.h>
19 #include <asm/tlbflush.h>
20 #include <asm/cacheflush.h>
21 #include <asm/mach/map.h>
22 
23 /**
24  * struct dbx500_asic_id - fields of the ASIC ID
25  * @process: the manufacturing process, 0x40 is 40 nm 0x00 is "standard"
26  * @partnumber: hithereto 0x8500 for DB8500
27  * @revision: version code in the series
28  */
29 struct dbx500_asic_id {
30 	u16	partnumber;
31 	u8	revision;
32 	u8	process;
33 };
34 
35 static struct dbx500_asic_id dbx500_id;
36 
37 static unsigned int __init ux500_read_asicid(phys_addr_t addr)
38 {
39 	void __iomem *virt = ioremap(addr, 4);
40 	unsigned int asicid;
41 
42 	if (!virt)
43 		return 0;
44 
45 	asicid = readl(virt);
46 	iounmap(virt);
47 
48 	return asicid;
49 }
50 
51 static void ux500_print_soc_info(unsigned int asicid)
52 {
53 	unsigned int rev = dbx500_id.revision;
54 
55 	pr_info("DB%4x ", dbx500_id.partnumber);
56 
57 	if (rev == 0x01)
58 		pr_cont("Early Drop");
59 	else if (rev >= 0xA0)
60 		pr_cont("v%d.%d" , (rev >> 4) - 0xA + 1, rev & 0xf);
61 	else
62 		pr_cont("Unknown");
63 
64 	pr_cont(" [%#010x]\n", asicid);
65 }
66 
67 static unsigned int partnumber(unsigned int asicid)
68 {
69 	return (asicid >> 8) & 0xffff;
70 }
71 
72 /*
73  * SOC		MIDR		ASICID ADDRESS		ASICID VALUE
74  * DB8500ed	0x410fc090	0x9001FFF4		0x00850001
75  * DB8500v1	0x411fc091	0x9001FFF4		0x008500A0
76  * DB8500v1.1	0x411fc091	0x9001FFF4		0x008500A1
77  * DB8500v2	0x412fc091	0x9001DBF4		0x008500B0
78  * DB8520v2.2	0x412fc091	0x9001DBF4		0x008500B2
79  * DB5500v1	0x412fc091	0x9001FFF4		0x005500A0
80  * DB9540	0x413fc090	0xFFFFDBF4		0x009540xx
81  */
82 
83 static void __init ux500_setup_id(void)
84 {
85 	unsigned int cpuid = read_cpuid_id();
86 	unsigned int asicid = 0;
87 	phys_addr_t addr = 0;
88 
89 	switch (cpuid) {
90 	case 0x410fc090: /* DB8500ed */
91 	case 0x411fc091: /* DB8500v1 */
92 		addr = 0x9001FFF4;
93 		break;
94 
95 	case 0x412fc091: /* DB8520 / DB8500v2 / DB5500v1 */
96 		asicid = ux500_read_asicid(0x9001DBF4);
97 		if (partnumber(asicid) == 0x8500 ||
98 		    partnumber(asicid) == 0x8520)
99 			/* DB8500v2 */
100 			break;
101 
102 		/* DB5500v1 */
103 		addr = 0x9001FFF4;
104 		break;
105 
106 	case 0x413fc090: /* DB9540 */
107 		addr = 0xFFFFDBF4;
108 		break;
109 	}
110 
111 	if (addr)
112 		asicid = ux500_read_asicid(addr);
113 
114 	if (!asicid) {
115 		pr_err("Unable to identify SoC\n");
116 		BUG();
117 	}
118 
119 	dbx500_id.process = asicid >> 24;
120 	dbx500_id.partnumber = partnumber(asicid);
121 	dbx500_id.revision = asicid & 0xff;
122 
123 	ux500_print_soc_info(asicid);
124 }
125 
126 static const char * __init ux500_get_machine(void)
127 {
128 	return kasprintf(GFP_KERNEL, "DB%4x", dbx500_id.partnumber);
129 }
130 
131 static const char * __init ux500_get_family(void)
132 {
133 	return kasprintf(GFP_KERNEL, "ux500");
134 }
135 
136 static const char * __init ux500_get_revision(void)
137 {
138 	unsigned int rev = dbx500_id.revision;
139 
140 	if (rev == 0x01)
141 		return kasprintf(GFP_KERNEL, "%s", "ED");
142 	else if (rev >= 0xA0)
143 		return kasprintf(GFP_KERNEL, "%d.%d",
144 				 (rev >> 4) - 0xA + 1, rev & 0xf);
145 
146 	return kasprintf(GFP_KERNEL, "%s", "Unknown");
147 }
148 
149 static ssize_t ux500_get_process(struct device *dev,
150 					struct device_attribute *attr,
151 					char *buf)
152 {
153 	if (dbx500_id.process == 0x00)
154 		return sprintf(buf, "Standard\n");
155 
156 	return sprintf(buf, "%02xnm\n", dbx500_id.process);
157 }
158 
159 static const char *db8500_read_soc_id(struct device_node *backupram)
160 {
161 	void __iomem *base;
162 	void __iomem *uid;
163 	const char *retstr;
164 
165 	base = of_iomap(backupram, 0);
166 	if (!base)
167 		return NULL;
168 	uid = base + 0x1fc0;
169 
170 	/* Throw these device-specific numbers into the entropy pool */
171 	add_device_randomness(uid, 0x14);
172 	retstr = kasprintf(GFP_KERNEL, "%08x%08x%08x%08x%08x",
173 			 readl((u32 *)uid+0),
174 			 readl((u32 *)uid+1), readl((u32 *)uid+2),
175 			 readl((u32 *)uid+3), readl((u32 *)uid+4));
176 	iounmap(base);
177 	return retstr;
178 }
179 
180 static void __init soc_info_populate(struct soc_device_attribute *soc_dev_attr,
181 				     struct device_node *backupram)
182 {
183 	soc_dev_attr->soc_id   = db8500_read_soc_id(backupram);
184 	soc_dev_attr->machine  = ux500_get_machine();
185 	soc_dev_attr->family   = ux500_get_family();
186 	soc_dev_attr->revision = ux500_get_revision();
187 }
188 
189 static const struct device_attribute ux500_soc_attr =
190 	__ATTR(process,  S_IRUGO, ux500_get_process,  NULL);
191 
192 static int __init ux500_soc_device_init(void)
193 {
194 	struct device *parent;
195 	struct soc_device *soc_dev;
196 	struct soc_device_attribute *soc_dev_attr;
197 	struct device_node *backupram;
198 
199 	backupram = of_find_compatible_node(NULL, NULL, "ste,dbx500-backupram");
200 	if (!backupram)
201 		return 0;
202 
203 	ux500_setup_id();
204 
205 	soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
206 	if (!soc_dev_attr) {
207 		of_node_put(backupram);
208 		return -ENOMEM;
209 	}
210 
211 	soc_info_populate(soc_dev_attr, backupram);
212 	of_node_put(backupram);
213 
214 	soc_dev = soc_device_register(soc_dev_attr);
215 	if (IS_ERR(soc_dev)) {
216 	        kfree(soc_dev_attr);
217 		return PTR_ERR(soc_dev);
218 	}
219 
220 	parent = soc_device_to_device(soc_dev);
221 	device_create_file(parent, &ux500_soc_attr);
222 
223 	return 0;
224 }
225 subsys_initcall(ux500_soc_device_init);
226