1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * Copyright 2020 Arm Limited |
4 | */ |
5 | |
6 | #define pr_fmt(fmt) "SMCCC: SOC_ID: " fmt |
7 | |
8 | #include <linux/arm-smccc.h> |
9 | #include <linux/bitfield.h> |
10 | #include <linux/device.h> |
11 | #include <linux/module.h> |
12 | #include <linux/kernel.h> |
13 | #include <linux/slab.h> |
14 | #include <linux/sys_soc.h> |
15 | |
16 | #define SMCCC_SOC_ID_JEP106_BANK_IDX_MASK GENMASK(30, 24) |
17 | /* |
18 | * As per the SMC Calling Convention specification v1.2 (ARM DEN 0028C) |
19 | * Section 7.4 SMCCC_ARCH_SOC_ID bits[23:16] are JEP-106 identification |
20 | * code with parity bit for the SiP. We can drop the parity bit. |
21 | */ |
22 | #define SMCCC_SOC_ID_JEP106_ID_CODE_MASK GENMASK(22, 16) |
23 | #define SMCCC_SOC_ID_IMP_DEF_SOC_ID_MASK GENMASK(15, 0) |
24 | |
25 | #define JEP106_BANK_CONT_CODE(x) \ |
26 | (u8)(FIELD_GET(SMCCC_SOC_ID_JEP106_BANK_IDX_MASK, (x))) |
27 | #define JEP106_ID_CODE(x) \ |
28 | (u8)(FIELD_GET(SMCCC_SOC_ID_JEP106_ID_CODE_MASK, (x))) |
29 | #define IMP_DEF_SOC_ID(x) \ |
30 | (u16)(FIELD_GET(SMCCC_SOC_ID_IMP_DEF_SOC_ID_MASK, (x))) |
31 | |
32 | static struct soc_device *soc_dev; |
33 | static struct soc_device_attribute *soc_dev_attr; |
34 | |
35 | static int __init smccc_soc_init(void) |
36 | { |
37 | int soc_id_rev, soc_id_version; |
38 | static char soc_id_str[20], soc_id_rev_str[12]; |
39 | static char soc_id_jep106_id_str[12]; |
40 | |
41 | if (arm_smccc_get_version() < ARM_SMCCC_VERSION_1_2) |
42 | return 0; |
43 | |
44 | soc_id_version = arm_smccc_get_soc_id_version(); |
45 | if (soc_id_version == SMCCC_RET_NOT_SUPPORTED) { |
46 | pr_info("ARCH_SOC_ID not implemented, skipping ....\n" ); |
47 | return 0; |
48 | } |
49 | |
50 | if (soc_id_version < 0) { |
51 | pr_err("Invalid SoC Version: %x\n" , soc_id_version); |
52 | return -EINVAL; |
53 | } |
54 | |
55 | soc_id_rev = arm_smccc_get_soc_id_revision(); |
56 | if (soc_id_rev < 0) { |
57 | pr_err("Invalid SoC Revision: %x\n" , soc_id_rev); |
58 | return -EINVAL; |
59 | } |
60 | |
61 | soc_dev_attr = kzalloc(size: sizeof(*soc_dev_attr), GFP_KERNEL); |
62 | if (!soc_dev_attr) |
63 | return -ENOMEM; |
64 | |
65 | sprintf(buf: soc_id_rev_str, fmt: "0x%08x" , soc_id_rev); |
66 | sprintf(buf: soc_id_jep106_id_str, fmt: "jep106:%02x%02x" , |
67 | JEP106_BANK_CONT_CODE(soc_id_version), |
68 | JEP106_ID_CODE(soc_id_version)); |
69 | sprintf(buf: soc_id_str, fmt: "%s:%04x" , soc_id_jep106_id_str, |
70 | IMP_DEF_SOC_ID(soc_id_version)); |
71 | |
72 | soc_dev_attr->soc_id = soc_id_str; |
73 | soc_dev_attr->revision = soc_id_rev_str; |
74 | soc_dev_attr->family = soc_id_jep106_id_str; |
75 | |
76 | soc_dev = soc_device_register(soc_plat_dev_attr: soc_dev_attr); |
77 | if (IS_ERR(ptr: soc_dev)) { |
78 | kfree(objp: soc_dev_attr); |
79 | return PTR_ERR(ptr: soc_dev); |
80 | } |
81 | |
82 | pr_info("ID = %s Revision = %s\n" , soc_dev_attr->soc_id, |
83 | soc_dev_attr->revision); |
84 | |
85 | return 0; |
86 | } |
87 | module_init(smccc_soc_init); |
88 | |
89 | static void __exit smccc_soc_exit(void) |
90 | { |
91 | if (soc_dev) |
92 | soc_device_unregister(soc_dev); |
93 | kfree(objp: soc_dev_attr); |
94 | } |
95 | module_exit(smccc_soc_exit); |
96 | |