1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2020 Arm Limited
4 */
5
6 #define pr_fmt(fmt) "smccc: " fmt
7
8 #include <linux/cache.h>
9 #include <linux/init.h>
10 #include <linux/arm-smccc.h>
11 #include <linux/kernel.h>
12 #include <linux/platform_device.h>
13 #include <asm/archrandom.h>
14
15 static u32 smccc_version = ARM_SMCCC_VERSION_1_0;
16 static enum arm_smccc_conduit smccc_conduit = SMCCC_CONDUIT_NONE;
17
18 bool __ro_after_init smccc_trng_available = false;
19 s32 __ro_after_init smccc_soc_id_version = SMCCC_RET_NOT_SUPPORTED;
20 s32 __ro_after_init smccc_soc_id_revision = SMCCC_RET_NOT_SUPPORTED;
21
arm_smccc_version_init(u32 version,enum arm_smccc_conduit conduit)22 void __init arm_smccc_version_init(u32 version, enum arm_smccc_conduit conduit)
23 {
24 struct arm_smccc_res res;
25
26 smccc_version = version;
27 smccc_conduit = conduit;
28
29 smccc_trng_available = smccc_probe_trng();
30
31 if ((smccc_version >= ARM_SMCCC_VERSION_1_2) &&
32 (smccc_conduit != SMCCC_CONDUIT_NONE)) {
33 arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_FEATURES_FUNC_ID,
34 ARM_SMCCC_ARCH_SOC_ID, &res);
35 if ((s32)res.a0 >= 0) {
36 arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_SOC_ID, 0, &res);
37 smccc_soc_id_version = (s32)res.a0;
38 arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_SOC_ID, 1, &res);
39 smccc_soc_id_revision = (s32)res.a0;
40 }
41 }
42 }
43
arm_smccc_1_1_get_conduit(void)44 enum arm_smccc_conduit arm_smccc_1_1_get_conduit(void)
45 {
46 if (smccc_version < ARM_SMCCC_VERSION_1_1)
47 return SMCCC_CONDUIT_NONE;
48
49 return smccc_conduit;
50 }
51 EXPORT_SYMBOL_GPL(arm_smccc_1_1_get_conduit);
52
arm_smccc_get_version(void)53 u32 arm_smccc_get_version(void)
54 {
55 return smccc_version;
56 }
57 EXPORT_SYMBOL_GPL(arm_smccc_get_version);
58
arm_smccc_get_soc_id_version(void)59 s32 arm_smccc_get_soc_id_version(void)
60 {
61 return smccc_soc_id_version;
62 }
63
arm_smccc_get_soc_id_revision(void)64 s32 arm_smccc_get_soc_id_revision(void)
65 {
66 return smccc_soc_id_revision;
67 }
68 EXPORT_SYMBOL_GPL(arm_smccc_get_soc_id_revision);
69
smccc_devices_init(void)70 static int __init smccc_devices_init(void)
71 {
72 struct platform_device *pdev;
73
74 if (smccc_trng_available) {
75 pdev = platform_device_register_simple("smccc_trng", -1,
76 NULL, 0);
77 if (IS_ERR(pdev))
78 pr_err("smccc_trng: could not register device: %ld\n",
79 PTR_ERR(pdev));
80 }
81
82 return 0;
83 }
84 device_initcall(smccc_devices_init);
85