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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright (C) 2020 Arm Limited4 */5 6#define pr_fmt(fmt) "smccc: " fmt7 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 15static u32 smccc_version = ARM_SMCCC_VERSION_1_0;16static enum arm_smccc_conduit smccc_conduit = SMCCC_CONDUIT_NONE;17 18bool __ro_after_init smccc_trng_available = false;19s32 __ro_after_init smccc_soc_id_version = SMCCC_RET_NOT_SUPPORTED;20s32 __ro_after_init smccc_soc_id_revision = SMCCC_RET_NOT_SUPPORTED;21 22void __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 44enum 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}51EXPORT_SYMBOL_GPL(arm_smccc_1_1_get_conduit);52 53u32 arm_smccc_get_version(void)54{55 return smccc_version;56}57EXPORT_SYMBOL_GPL(arm_smccc_get_version);58 59s32 arm_smccc_get_soc_id_version(void)60{61 return smccc_soc_id_version;62}63 64s32 arm_smccc_get_soc_id_revision(void)65{66 return smccc_soc_id_revision;67}68EXPORT_SYMBOL_GPL(arm_smccc_get_soc_id_revision);69 70static 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}84device_initcall(smccc_devices_init);85