1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright 2024 NXP
4 */
5
6 #include <linux/arm-smccc.h>
7 #include <linux/init.h>
8 #include <linux/module.h>
9 #include <linux/of.h>
10 #include <linux/platform_device.h>
11 #include <linux/slab.h>
12 #include <linux/sys_soc.h>
13
14 #define IMX_SIP_GET_SOC_INFO 0xc2000006
15 #define SOC_ID(x) (((x) & 0xFFFF) >> 8)
16 #define SOC_REV_MAJOR(x) ((((x) >> 28) & 0xF) - 0x9)
17 #define SOC_REV_MINOR(x) (((x) >> 24) & 0xF)
18
imx9_soc_probe(struct platform_device * pdev)19 static int imx9_soc_probe(struct platform_device *pdev)
20 {
21 struct soc_device_attribute *attr;
22 struct arm_smccc_res res;
23 struct soc_device *sdev;
24 u32 soc_id, rev_major, rev_minor;
25 u64 uid127_64, uid63_0;
26 int err;
27
28 attr = kzalloc(sizeof(*attr), GFP_KERNEL);
29 if (!attr)
30 return -ENOMEM;
31
32 err = of_property_read_string(of_root, "model", &attr->machine);
33 if (err) {
34 pr_err("%s: missing model property: %d\n", __func__, err);
35 goto attr;
36 }
37
38 attr->family = kasprintf(GFP_KERNEL, "Freescale i.MX");
39
40 /*
41 * Retrieve the soc id, rev & uid info:
42 * res.a1[31:16]: soc revision;
43 * res.a1[15:0]: soc id;
44 * res.a2: uid[127:64];
45 * res.a3: uid[63:0];
46 */
47 arm_smccc_smc(IMX_SIP_GET_SOC_INFO, 0, 0, 0, 0, 0, 0, 0, &res);
48 if (res.a0 != SMCCC_RET_SUCCESS) {
49 pr_err("%s: SMC failed: 0x%lx\n", __func__, res.a0);
50 err = -EINVAL;
51 goto family;
52 }
53
54 soc_id = SOC_ID(res.a1);
55 rev_major = SOC_REV_MAJOR(res.a1);
56 rev_minor = SOC_REV_MINOR(res.a1);
57
58 attr->soc_id = kasprintf(GFP_KERNEL, "i.MX%2x", soc_id);
59 attr->revision = kasprintf(GFP_KERNEL, "%d.%d", rev_major, rev_minor);
60
61 uid127_64 = res.a2;
62 uid63_0 = res.a3;
63 attr->serial_number = kasprintf(GFP_KERNEL, "%016llx%016llx", uid127_64, uid63_0);
64
65 sdev = soc_device_register(attr);
66 if (IS_ERR(sdev)) {
67 err = PTR_ERR(sdev);
68 pr_err("%s failed to register SoC as a device: %d\n", __func__, err);
69 goto serial_number;
70 }
71
72 return 0;
73
74 serial_number:
75 kfree(attr->serial_number);
76 kfree(attr->revision);
77 kfree(attr->soc_id);
78 family:
79 kfree(attr->family);
80 attr:
81 kfree(attr);
82 return err;
83 }
84
85 static __maybe_unused const struct of_device_id imx9_soc_match[] = {
86 { .compatible = "fsl,imx93", },
87 { .compatible = "fsl,imx95", },
88 { }
89 };
90
91 #define IMX_SOC_DRIVER "imx9-soc"
92
93 static struct platform_driver imx9_soc_driver = {
94 .probe = imx9_soc_probe,
95 .driver = {
96 .name = IMX_SOC_DRIVER,
97 },
98 };
99
imx9_soc_init(void)100 static int __init imx9_soc_init(void)
101 {
102 int ret;
103 struct platform_device *pdev;
104
105 /* No match means it is not an i.MX 9 series SoC, do nothing. */
106 if (!of_match_node(imx9_soc_match, of_root))
107 return 0;
108
109 ret = platform_driver_register(&imx9_soc_driver);
110 if (ret) {
111 pr_err("failed to register imx9_soc platform driver: %d\n", ret);
112 return ret;
113 }
114
115 pdev = platform_device_register_simple(IMX_SOC_DRIVER, -1, NULL, 0);
116 if (IS_ERR(pdev)) {
117 pr_err("failed to register imx9_soc platform device: %ld\n", PTR_ERR(pdev));
118 platform_driver_unregister(&imx9_soc_driver);
119 return PTR_ERR(pdev);
120 }
121
122 return 0;
123 }
124 device_initcall(imx9_soc_init);
125
126 MODULE_AUTHOR("NXP");
127 MODULE_DESCRIPTION("NXP i.MX9 SoC");
128 MODULE_LICENSE("GPL");
129