1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Copyright 2020 Arm Limited
4*4882a593Smuzhiyun */
5*4882a593Smuzhiyun
6*4882a593Smuzhiyun #define pr_fmt(fmt) "SMCCC: SOC_ID: " fmt
7*4882a593Smuzhiyun
8*4882a593Smuzhiyun #include <linux/arm-smccc.h>
9*4882a593Smuzhiyun #include <linux/bitfield.h>
10*4882a593Smuzhiyun #include <linux/device.h>
11*4882a593Smuzhiyun #include <linux/module.h>
12*4882a593Smuzhiyun #include <linux/kernel.h>
13*4882a593Smuzhiyun #include <linux/slab.h>
14*4882a593Smuzhiyun #include <linux/sys_soc.h>
15*4882a593Smuzhiyun
16*4882a593Smuzhiyun #define SMCCC_SOC_ID_JEP106_BANK_IDX_MASK GENMASK(30, 24)
17*4882a593Smuzhiyun /*
18*4882a593Smuzhiyun * As per the SMC Calling Convention specification v1.2 (ARM DEN 0028C)
19*4882a593Smuzhiyun * Section 7.4 SMCCC_ARCH_SOC_ID bits[23:16] are JEP-106 identification
20*4882a593Smuzhiyun * code with parity bit for the SiP. We can drop the parity bit.
21*4882a593Smuzhiyun */
22*4882a593Smuzhiyun #define SMCCC_SOC_ID_JEP106_ID_CODE_MASK GENMASK(22, 16)
23*4882a593Smuzhiyun #define SMCCC_SOC_ID_IMP_DEF_SOC_ID_MASK GENMASK(15, 0)
24*4882a593Smuzhiyun
25*4882a593Smuzhiyun #define JEP106_BANK_CONT_CODE(x) \
26*4882a593Smuzhiyun (u8)(FIELD_GET(SMCCC_SOC_ID_JEP106_BANK_IDX_MASK, (x)))
27*4882a593Smuzhiyun #define JEP106_ID_CODE(x) \
28*4882a593Smuzhiyun (u8)(FIELD_GET(SMCCC_SOC_ID_JEP106_ID_CODE_MASK, (x)))
29*4882a593Smuzhiyun #define IMP_DEF_SOC_ID(x) \
30*4882a593Smuzhiyun (u16)(FIELD_GET(SMCCC_SOC_ID_IMP_DEF_SOC_ID_MASK, (x)))
31*4882a593Smuzhiyun
32*4882a593Smuzhiyun static struct soc_device *soc_dev;
33*4882a593Smuzhiyun static struct soc_device_attribute *soc_dev_attr;
34*4882a593Smuzhiyun
smccc_soc_init(void)35*4882a593Smuzhiyun static int __init smccc_soc_init(void)
36*4882a593Smuzhiyun {
37*4882a593Smuzhiyun struct arm_smccc_res res;
38*4882a593Smuzhiyun int soc_id_rev, soc_id_version;
39*4882a593Smuzhiyun static char soc_id_str[20], soc_id_rev_str[12];
40*4882a593Smuzhiyun static char soc_id_jep106_id_str[12];
41*4882a593Smuzhiyun
42*4882a593Smuzhiyun if (arm_smccc_get_version() < ARM_SMCCC_VERSION_1_2)
43*4882a593Smuzhiyun return 0;
44*4882a593Smuzhiyun
45*4882a593Smuzhiyun if (arm_smccc_1_1_get_conduit() == SMCCC_CONDUIT_NONE) {
46*4882a593Smuzhiyun pr_err("%s: invalid SMCCC conduit\n", __func__);
47*4882a593Smuzhiyun return -EOPNOTSUPP;
48*4882a593Smuzhiyun }
49*4882a593Smuzhiyun
50*4882a593Smuzhiyun arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_FEATURES_FUNC_ID,
51*4882a593Smuzhiyun ARM_SMCCC_ARCH_SOC_ID, &res);
52*4882a593Smuzhiyun
53*4882a593Smuzhiyun if ((int)res.a0 == SMCCC_RET_NOT_SUPPORTED) {
54*4882a593Smuzhiyun pr_info("ARCH_SOC_ID not implemented, skipping ....\n");
55*4882a593Smuzhiyun return 0;
56*4882a593Smuzhiyun }
57*4882a593Smuzhiyun
58*4882a593Smuzhiyun if ((int)res.a0 < 0) {
59*4882a593Smuzhiyun pr_info("ARCH_FEATURES(ARCH_SOC_ID) returned error: %lx\n",
60*4882a593Smuzhiyun res.a0);
61*4882a593Smuzhiyun return -EINVAL;
62*4882a593Smuzhiyun }
63*4882a593Smuzhiyun
64*4882a593Smuzhiyun arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_SOC_ID, 0, &res);
65*4882a593Smuzhiyun if ((int)res.a0 < 0) {
66*4882a593Smuzhiyun pr_err("ARCH_SOC_ID(0) returned error: %lx\n", res.a0);
67*4882a593Smuzhiyun return -EINVAL;
68*4882a593Smuzhiyun }
69*4882a593Smuzhiyun
70*4882a593Smuzhiyun soc_id_version = res.a0;
71*4882a593Smuzhiyun
72*4882a593Smuzhiyun arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_SOC_ID, 1, &res);
73*4882a593Smuzhiyun if ((int)res.a0 < 0) {
74*4882a593Smuzhiyun pr_err("ARCH_SOC_ID(1) returned error: %lx\n", res.a0);
75*4882a593Smuzhiyun return -EINVAL;
76*4882a593Smuzhiyun }
77*4882a593Smuzhiyun
78*4882a593Smuzhiyun soc_id_rev = res.a0;
79*4882a593Smuzhiyun
80*4882a593Smuzhiyun soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
81*4882a593Smuzhiyun if (!soc_dev_attr)
82*4882a593Smuzhiyun return -ENOMEM;
83*4882a593Smuzhiyun
84*4882a593Smuzhiyun sprintf(soc_id_rev_str, "0x%08x", soc_id_rev);
85*4882a593Smuzhiyun sprintf(soc_id_jep106_id_str, "jep106:%02x%02x",
86*4882a593Smuzhiyun JEP106_BANK_CONT_CODE(soc_id_version),
87*4882a593Smuzhiyun JEP106_ID_CODE(soc_id_version));
88*4882a593Smuzhiyun sprintf(soc_id_str, "%s:%04x", soc_id_jep106_id_str,
89*4882a593Smuzhiyun IMP_DEF_SOC_ID(soc_id_version));
90*4882a593Smuzhiyun
91*4882a593Smuzhiyun soc_dev_attr->soc_id = soc_id_str;
92*4882a593Smuzhiyun soc_dev_attr->revision = soc_id_rev_str;
93*4882a593Smuzhiyun soc_dev_attr->family = soc_id_jep106_id_str;
94*4882a593Smuzhiyun
95*4882a593Smuzhiyun soc_dev = soc_device_register(soc_dev_attr);
96*4882a593Smuzhiyun if (IS_ERR(soc_dev)) {
97*4882a593Smuzhiyun kfree(soc_dev_attr);
98*4882a593Smuzhiyun return PTR_ERR(soc_dev);
99*4882a593Smuzhiyun }
100*4882a593Smuzhiyun
101*4882a593Smuzhiyun pr_info("ID = %s Revision = %s\n", soc_dev_attr->soc_id,
102*4882a593Smuzhiyun soc_dev_attr->revision);
103*4882a593Smuzhiyun
104*4882a593Smuzhiyun return 0;
105*4882a593Smuzhiyun }
106*4882a593Smuzhiyun module_init(smccc_soc_init);
107*4882a593Smuzhiyun
smccc_soc_exit(void)108*4882a593Smuzhiyun static void __exit smccc_soc_exit(void)
109*4882a593Smuzhiyun {
110*4882a593Smuzhiyun if (soc_dev)
111*4882a593Smuzhiyun soc_device_unregister(soc_dev);
112*4882a593Smuzhiyun kfree(soc_dev_attr);
113*4882a593Smuzhiyun }
114*4882a593Smuzhiyun module_exit(smccc_soc_exit);
115