/* * Copyright (c) 2022-2023, Arm Limited and Contributors. All rights reserved. * * SPDX-License-Identifier: BSD-3-Clause */ #include #include #include static bool tainted; /******************************************************************************* * This section lists the wrapper modules for each feature to evaluate the * feature states (FEAT_STATE_ALWAYS and FEAT_STATE_CHECK) and perform * necessary action as below: * * It verifies whether the FEAT_XXX (eg: FEAT_SB) is supported by the PE or not. * Without this check an exception would occur during context save/restore * routines, if the feature is enabled but not supported by PE. ******************************************************************************/ #define feat_detect_panic(a, b) ((a) ? (void)0 : feature_panic(b)) /******************************************************************************* * Function : feature_panic * Customised panic function with error logging mechanism to list the feature * not supported by the PE. ******************************************************************************/ static inline void feature_panic(char *feat_name) { ERROR("FEAT_%s not supported by the PE\n", feat_name); panic(); } /******************************************************************************* * Function : check_feature * Check for a valid combination of build time flags (ENABLE_FEAT_xxx) and * feature availability on the hardware. is the smallest feature * ID field value that is required for that feature. * Triggers a panic later if a feature is forcefully enabled, but not * available on the PE. Also will panic if the hardware feature ID field * is larger than the maximum known and supported number, specified by . * * We force inlining here to let the compiler optimise away the whole check * if the feature is disabled at build time (FEAT_STATE_DISABLED). ******************************************************************************/ static inline void __attribute((__always_inline__)) check_feature(int state, unsigned long field, const char *feat_name, unsigned int min, unsigned int max) { if (state == FEAT_STATE_ALWAYS && field < min) { ERROR("FEAT_%s not supported by the PE\n", feat_name); tainted = true; } if (state >= FEAT_STATE_ALWAYS && field > max) { ERROR("FEAT_%s is version %ld, but is only known up to version %d\n", feat_name, field, max); tainted = true; } } /************************************************ * Feature : FEAT_PAUTH (Pointer Authentication) ***********************************************/ static void read_feat_pauth(void) { #if (ENABLE_PAUTH == FEAT_STATE_ALWAYS) || (CTX_INCLUDE_PAUTH_REGS == FEAT_STATE_ALWAYS) feat_detect_panic(is_armv8_3_pauth_present(), "PAUTH"); #endif } /************************************************ * Feature : FEAT_MTE (Memory Tagging Extension) ***********************************************/ static void read_feat_mte(void) { #if (CTX_INCLUDE_MTE_REGS == FEAT_STATE_ALWAYS) unsigned int mte = get_armv8_5_mte_support(); feat_detect_panic((mte != MTE_UNIMPLEMENTED), "MTE"); #endif } /**************************************************** * Feature : FEAT_BTI (Branch Target Identification) ***************************************************/ static void read_feat_bti(void) { #if (ENABLE_BTI == FEAT_STATE_ALWAYS) feat_detect_panic(is_armv8_5_bti_present(), "BTI"); #endif } /************************************************** * Feature : FEAT_RME (Realm Management Extension) *************************************************/ static void read_feat_rme(void) { #if (ENABLE_RME == FEAT_STATE_ALWAYS) feat_detect_panic((get_armv9_2_feat_rme_support() != ID_AA64PFR0_FEAT_RME_NOT_SUPPORTED), "RME"); #endif } /****************************************************************** * Feature : FEAT_RNG_TRAP (Trapping support for RNDR/RNDRRS) *****************************************************************/ static void read_feat_rng_trap(void) { #if (ENABLE_FEAT_RNG_TRAP == FEAT_STATE_ALWAYS) feat_detect_panic(is_feat_rng_trap_present(), "RNG_TRAP"); #endif } /*********************************************************************************** * TF-A supports many Arm architectural features starting from arch version * (8.0 till 8.7+). These features are mostly enabled through build flags. This * mechanism helps in validating these build flags in the early boot phase * either in BL1 or BL31 depending on the platform and assists in identifying * and notifying the features which are enabled but not supported by the PE. * * It reads all the enabled features ID-registers and ensures the features * are supported by the PE. * In case if they aren't it stops booting at an early phase and logs the error * messages, notifying the platforms about the features that are not supported. * * Further the procedure is implemented with a tri-state approach for each feature: * ENABLE_FEAT_xxx = 0 : The feature is disabled statically at compile time * ENABLE_FEAT_xxx = 1 : The feature is enabled and must be present in hardware. * There will be panic if feature is not present at cold boot. * ENABLE_FEAT_xxx = 2 : The feature is enabled but dynamically enabled at runtime * depending on hardware capability. * * For better readability, state values are defined with macros, namely: * { FEAT_STATE_DISABLED, FEAT_STATE_ALWAYS, FEAT_STATE_CHECK }, taking values * { 0, 1, 2 }, respectively, as their naming. **********************************************************************************/ void detect_arch_features(void) { tainted = false; /* v8.0 features */ check_feature(ENABLE_FEAT_SB, read_feat_sb_id_field(), "SB", 1, 1); check_feature(ENABLE_FEAT_CSV2_2, read_feat_csv2_id_field(), "CSV2_2", 2, 3); /* * Even though the PMUv3 is an OPTIONAL feature, it is always * implemented and Arm prescribes so. So assume it will be there and do * away with a flag for it. This is used to check minor PMUv3px * revisions so that we catch them as they come along */ check_feature(FEAT_STATE_ALWAYS, read_feat_pmuv3_id_field(), "PMUv3", 1, ID_AA64DFR0_PMUVER_PMUV3P7); /* v8.1 features */ check_feature(ENABLE_FEAT_PAN, read_feat_pan_id_field(), "PAN", 1, 3); check_feature(ENABLE_FEAT_VHE, read_feat_vhe_id_field(), "VHE", 1, 1); /* v8.2 features */ check_feature(ENABLE_SVE_FOR_NS, read_feat_sve_id_field(), "SVE", 1, 1); check_feature(ENABLE_FEAT_RAS, read_feat_ras_id_field(), "RAS", 1, 2); /* v8.3 features */ read_feat_pauth(); /* v8.4 features */ check_feature(ENABLE_FEAT_DIT, read_feat_dit_id_field(), "DIT", 1, 1); check_feature(ENABLE_FEAT_AMU, read_feat_amu_id_field(), "AMUv1", 1, 2); check_feature(ENABLE_FEAT_MPAM, read_feat_mpam_version(), "MPAM", 1, 17); check_feature(CTX_INCLUDE_NEVE_REGS, read_feat_nv_id_field(), "NV2", 2, 2); check_feature(ENABLE_FEAT_SEL2, read_feat_sel2_id_field(), "SEL2", 1, 1); check_feature(ENABLE_TRF_FOR_NS, read_feat_trf_id_field(), "TRF", 1, 1); /* v8.5 features */ read_feat_mte(); check_feature(ENABLE_FEAT_RNG, read_feat_rng_id_field(), "RNG", 1, 1); read_feat_bti(); read_feat_rng_trap(); /* v8.6 features */ check_feature(ENABLE_FEAT_AMUv1p1, read_feat_amu_id_field(), "AMUv1p1", 2, 2); check_feature(ENABLE_FEAT_FGT, read_feat_fgt_id_field(), "FGT", 1, 1); check_feature(ENABLE_FEAT_ECV, read_feat_ecv_id_field(), "ECV", 1, 2); check_feature(ENABLE_FEAT_TWED, read_feat_twed_id_field(), "TWED", 1, 1); /* * even though this is a "DISABLE" it does confusingly perform feature * enablement duties like all other flags here. Check it against the HW * feature when we intend to diverge from the default behaviour */ check_feature(DISABLE_MTPMU, read_feat_mtpmu_id_field(), "MTPMU", 1, 1); /* v8.7 features */ check_feature(ENABLE_FEAT_HCX, read_feat_hcx_id_field(), "HCX", 1, 1); /* v8.9 features */ check_feature(ENABLE_FEAT_TCR2, read_feat_tcr2_id_field(), "TCR2", 1, 1); check_feature(ENABLE_FEAT_S2PIE, read_feat_s2pie_id_field(), "S2PIE", 1, 1); check_feature(ENABLE_FEAT_S1PIE, read_feat_s1pie_id_field(), "S1PIE", 1, 1); check_feature(ENABLE_FEAT_S2POE, read_feat_s2poe_id_field(), "S2POE", 1, 1); check_feature(ENABLE_FEAT_S1POE, read_feat_s1poe_id_field(), "S1POE", 1, 1); check_feature(ENABLE_FEAT_MTE_PERM, read_feat_mte_perm_id_field(), "MTE_PERM", 1, 1); /* v9.0 features */ check_feature(ENABLE_BRBE_FOR_NS, read_feat_brbe_id_field(), "BRBE", 1, 2); check_feature(ENABLE_TRBE_FOR_NS, read_feat_trbe_id_field(), "TRBE", 1, 1); /* v9.2 features */ check_feature(ENABLE_SME_FOR_NS, read_feat_sme_id_field(), "SME", 1, 2); check_feature(ENABLE_SME2_FOR_NS, read_feat_sme_id_field(), "SME2", 2, 2); /* v9.4 features */ check_feature(ENABLE_FEAT_GCS, read_feat_gcs_id_field(), "GCS", 1, 1); read_feat_rme(); if (tainted) { panic(); } }