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 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 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 53 u32 arm_smccc_get_version(void) 54 { 55 return smccc_version; 56 } 57 EXPORT_SYMBOL_GPL(arm_smccc_get_version); 58 59 s32 arm_smccc_get_soc_id_version(void) 60 { 61 return smccc_soc_id_version; 62 } 63 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 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