1 /* 2 * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved. 3 * 4 * SPDX-License-Identifier: BSD-3-Clause 5 */ 6 7 #include <arm_arch_svc.h> 8 #include <debug.h> 9 #include <runtime_svc.h> 10 #include <smcc.h> 11 #include <smcc_helpers.h> 12 13 static int32_t smccc_version(void) 14 { 15 return MAKE_SMCCC_VERSION(SMCCC_MAJOR_VERSION, SMCCC_MINOR_VERSION); 16 } 17 18 static int32_t smccc_arch_features(u_register_t arg) 19 { 20 switch (arg) { 21 case SMCCC_VERSION: 22 case SMCCC_ARCH_FEATURES: 23 return SMC_OK; 24 #if WORKAROUND_CVE_2017_5715 25 case SMCCC_ARCH_WORKAROUND_1: 26 return SMC_OK; 27 #endif 28 default: 29 return SMC_UNK; 30 } 31 } 32 33 /* 34 * Top-level Arm Architectural Service SMC handler. 35 */ 36 static uintptr_t arm_arch_svc_smc_handler(uint32_t smc_fid, 37 u_register_t x1, 38 u_register_t x2, 39 u_register_t x3, 40 u_register_t x4, 41 void *cookie, 42 void *handle, 43 u_register_t flags) 44 { 45 switch (smc_fid) { 46 case SMCCC_VERSION: 47 SMC_RET1(handle, smccc_version()); 48 case SMCCC_ARCH_FEATURES: 49 SMC_RET1(handle, smccc_arch_features(x1)); 50 #if WORKAROUND_CVE_2017_5715 51 case SMCCC_ARCH_WORKAROUND_1: 52 /* 53 * The workaround has already been applied on affected PEs 54 * during entry to EL3. On unaffected PEs, this function 55 * has no effect. 56 */ 57 SMC_RET0(handle); 58 #endif 59 default: 60 WARN("Unimplemented Arm Architecture Service Call: 0x%x \n", 61 smc_fid); 62 SMC_RET1(handle, SMC_UNK); 63 } 64 } 65 66 /* Register Standard Service Calls as runtime service */ 67 DECLARE_RT_SVC( 68 arm_arch_svc, 69 OEN_ARM_START, 70 OEN_ARM_END, 71 SMC_TYPE_FAST, 72 NULL, 73 arm_arch_svc_smc_handler 74 ); 75