1 /* 2 * Copyright (c) 2022, Arm Limited and Contributors. All rights reserved. 3 * 4 * SPDX-License-Identifier: BSD-3-Clause 5 */ 6 7 #include <arch_features.h> 8 #include <common/debug.h> 9 #include <common/feat_detect.h> 10 11 static bool tainted; 12 13 /******************************************************************************* 14 * This section lists the wrapper modules for each feature to evaluate the 15 * feature states (FEAT_STATE_ALWAYS and FEAT_STATE_CHECK) and perform 16 * necessary action as below: 17 * 18 * It verifies whether the FEAT_XXX (eg: FEAT_SB) is supported by the PE or not. 19 * Without this check an exception would occur during context save/restore 20 * routines, if the feature is enabled but not supported by PE. 21 ******************************************************************************/ 22 23 #define feat_detect_panic(a, b) ((a) ? (void)0 : feature_panic(b)) 24 25 /******************************************************************************* 26 * Function : feature_panic 27 * Customised panic function with error logging mechanism to list the feature 28 * not supported by the PE. 29 ******************************************************************************/ 30 static inline void feature_panic(char *feat_name) 31 { 32 ERROR("FEAT_%s not supported by the PE\n", feat_name); 33 panic(); 34 } 35 36 /******************************************************************************* 37 * Function : check_feature 38 * Check for a valid combination of build time flags (ENABLE_FEAT_xxx) and 39 * feature availability on the hardware. <min> is the smallest feature 40 * ID field value that is required for that feature. 41 * Triggers a panic later if a feature is forcefully enabled, but not 42 * available on the PE. Also will panic if the hardware feature ID field 43 * is larger than the maximum known and supported number, specified by <max>. 44 * 45 * We force inlining here to let the compiler optimise away the whole check 46 * if the feature is disabled at build time (FEAT_STATE_DISABLED). 47 ******************************************************************************/ 48 static inline void __attribute((__always_inline__)) 49 check_feature(int state, unsigned long field, const char *feat_name, 50 unsigned int min, unsigned int max) 51 { 52 if (state == FEAT_STATE_ALWAYS && field < min) { 53 ERROR("FEAT_%s not supported by the PE\n", feat_name); 54 tainted = true; 55 } 56 if (state >= FEAT_STATE_ALWAYS && field > max) { 57 ERROR("FEAT_%s is version %ld, but is only known up to version %d\n", 58 feat_name, field, max); 59 tainted = true; 60 } 61 } 62 63 /****************************************** 64 * Feature : FEAT_SB (Speculation Barrier) 65 *****************************************/ 66 static void read_feat_sb(void) 67 { 68 #if (ENABLE_FEAT_SB == FEAT_STATE_ALWAYS) 69 feat_detect_panic(is_armv8_0_feat_sb_present(), "SB"); 70 #endif 71 } 72 73 /****************************************************** 74 * Feature : FEAT_CSV2_2 (Cache Speculation Variant 2) 75 *****************************************************/ 76 static void read_feat_csv2_2(void) 77 { 78 #if (ENABLE_FEAT_CSV2_2 == FEAT_STATE_ALWAYS) 79 feat_detect_panic(is_armv8_0_feat_csv2_2_present(), "CSV2_2"); 80 #endif 81 } 82 83 /*********************************************** 84 * Feature : FEAT_PAN (Privileged Access Never) 85 **********************************************/ 86 static void read_feat_pan(void) 87 { 88 #if (ENABLE_FEAT_PAN == FEAT_STATE_ALWAYS) 89 feat_detect_panic(is_armv8_1_pan_present(), "PAN"); 90 #endif 91 } 92 93 /****************************************************** 94 * Feature : FEAT_VHE (Virtualization Host Extensions) 95 *****************************************************/ 96 static void read_feat_vhe(void) 97 { 98 #if (ENABLE_FEAT_VHE == FEAT_STATE_ALWAYS) 99 feat_detect_panic(is_armv8_1_vhe_present(), "VHE"); 100 #endif 101 } 102 103 /******************************************************************************* 104 * Feature : FEAT_RAS (Reliability, Availability, and Serviceability Extension) 105 ******************************************************************************/ 106 static void read_feat_ras(void) 107 { 108 #if (RAS_EXTENSION == FEAT_STATE_ALWAYS) 109 feat_detect_panic(is_armv8_2_feat_ras_present(), "RAS"); 110 #endif 111 } 112 113 /************************************************ 114 * Feature : FEAT_PAUTH (Pointer Authentication) 115 ***********************************************/ 116 static void read_feat_pauth(void) 117 { 118 #if (ENABLE_PAUTH == FEAT_STATE_ALWAYS) || (CTX_INCLUDE_PAUTH_REGS == FEAT_STATE_ALWAYS) 119 feat_detect_panic(is_armv8_3_pauth_present(), "PAUTH"); 120 #endif 121 } 122 123 /************************************************************ 124 * Feature : FEAT_DIT (Data Independent Timing Instructions) 125 ***********************************************************/ 126 static void read_feat_dit(void) 127 { 128 #if (ENABLE_FEAT_DIT == FEAT_STATE_ALWAYS) 129 feat_detect_panic(is_armv8_4_feat_dit_present(), "DIT"); 130 #endif 131 } 132 133 /**************************************************************************** 134 * Feature : FEAT_MPAM (Memory Partitioning and Monitoring (MPAM) Extension) 135 ***************************************************************************/ 136 static void read_feat_mpam(void) 137 { 138 #if (ENABLE_MPAM_FOR_LOWER_ELS == FEAT_STATE_ALWAYS) 139 feat_detect_panic(get_mpam_version() != 0U, "MPAM"); 140 #endif 141 } 142 143 /************************************************************** 144 * Feature : FEAT_NV2 (Enhanced Nested Virtualization Support) 145 *************************************************************/ 146 static void read_feat_nv2(void) 147 { 148 #if (CTX_INCLUDE_NEVE_REGS == FEAT_STATE_ALWAYS) 149 unsigned int nv = get_armv8_4_feat_nv_support(); 150 151 feat_detect_panic((nv == ID_AA64MMFR2_EL1_NV2_SUPPORTED), "NV2"); 152 #endif 153 } 154 155 /*********************************** 156 * Feature : FEAT_SEL2 (Secure EL2) 157 **********************************/ 158 static void read_feat_sel2(void) 159 { 160 #if (ENABLE_FEAT_SEL2 == FEAT_STATE_ALWAYS) 161 feat_detect_panic(is_armv8_4_sel2_present(), "SEL2"); 162 #endif 163 } 164 165 /**************************************************** 166 * Feature : FEAT_TRF (Self-hosted Trace Extensions) 167 ***************************************************/ 168 static void read_feat_trf(void) 169 { 170 #if (ENABLE_TRF_FOR_NS == FEAT_STATE_ALWAYS) 171 feat_detect_panic(is_arm8_4_feat_trf_present(), "TRF"); 172 #endif 173 } 174 175 /************************************************ 176 * Feature : FEAT_MTE (Memory Tagging Extension) 177 ***********************************************/ 178 static void read_feat_mte(void) 179 { 180 #if (CTX_INCLUDE_MTE_REGS == FEAT_STATE_ALWAYS) 181 unsigned int mte = get_armv8_5_mte_support(); 182 183 feat_detect_panic((mte != MTE_UNIMPLEMENTED), "MTE"); 184 #endif 185 } 186 187 /*********************************************** 188 * Feature : FEAT_RNG (Random Number Generator) 189 **********************************************/ 190 static void read_feat_rng(void) 191 { 192 #if (ENABLE_FEAT_RNG == FEAT_STATE_ALWAYS) 193 feat_detect_panic(is_armv8_5_rng_present(), "RNG"); 194 #endif 195 } 196 197 /**************************************************** 198 * Feature : FEAT_BTI (Branch Target Identification) 199 ***************************************************/ 200 static void read_feat_bti(void) 201 { 202 #if (ENABLE_BTI == FEAT_STATE_ALWAYS) 203 feat_detect_panic(is_armv8_5_bti_present(), "BTI"); 204 #endif 205 } 206 207 /*********************************************** 208 * Feature : FEAT_AMUv1p1 (AMU Extensions v1.1) 209 **********************************************/ 210 static void read_feat_amuv1p1(void) 211 { 212 #if (ENABLE_FEAT_AMUv1p1 == FEAT_STATE_ALWAYS) 213 feat_detect_panic(is_armv8_6_feat_amuv1p1_present(), "AMUv1p1"); 214 #endif 215 } 216 217 /******************************************************* 218 * Feature : FEAT_ECV (Enhanced Counter Virtualization) 219 ******************************************************/ 220 static void read_feat_ecv(void) 221 { 222 #if (ENABLE_FEAT_ECV == FEAT_STATE_ALWAYS) 223 unsigned int ecv = get_armv8_6_ecv_support(); 224 225 feat_detect_panic(((ecv == ID_AA64MMFR0_EL1_ECV_SUPPORTED) || 226 (ecv == ID_AA64MMFR0_EL1_ECV_SELF_SYNCH)), "ECV"); 227 #endif 228 } 229 230 /*********************************************************** 231 * Feature : FEAT_TWED (Delayed Trapping of WFE Instruction) 232 **********************************************************/ 233 static void read_feat_twed(void) 234 { 235 #if (ENABLE_FEAT_TWED == FEAT_STATE_ALWAYS) 236 feat_detect_panic(is_armv8_6_twed_present(), "TWED"); 237 #endif 238 } 239 240 /************************************************** 241 * Feature : FEAT_RME (Realm Management Extension) 242 *************************************************/ 243 static void read_feat_rme(void) 244 { 245 #if (ENABLE_RME == FEAT_STATE_ALWAYS) 246 feat_detect_panic((get_armv9_2_feat_rme_support() != 247 ID_AA64PFR0_FEAT_RME_NOT_SUPPORTED), "RME"); 248 #endif 249 } 250 251 /****************************************************************** 252 * Feature : FEAT_RNG_TRAP (Trapping support for RNDR/RNDRRS) 253 *****************************************************************/ 254 static void read_feat_rng_trap(void) 255 { 256 #if (ENABLE_FEAT_RNG_TRAP == FEAT_STATE_ALWAYS) 257 feat_detect_panic(is_feat_rng_trap_present(), "RNG_TRAP"); 258 #endif 259 } 260 261 /*********************************************************************************** 262 * TF-A supports many Arm architectural features starting from arch version 263 * (8.0 till 8.7+). These features are mostly enabled through build flags. This 264 * mechanism helps in validating these build flags in the early boot phase 265 * either in BL1 or BL31 depending on the platform and assists in identifying 266 * and notifying the features which are enabled but not supported by the PE. 267 * 268 * It reads all the enabled features ID-registers and ensures the features 269 * are supported by the PE. 270 * In case if they aren't it stops booting at an early phase and logs the error 271 * messages, notifying the platforms about the features that are not supported. 272 * 273 * Further the procedure is implemented with a tri-state approach for each feature: 274 * ENABLE_FEAT_xxx = 0 : The feature is disabled statically at compile time 275 * ENABLE_FEAT_xxx = 1 : The feature is enabled and must be present in hardware. 276 * There will be panic if feature is not present at cold boot. 277 * ENABLE_FEAT_xxx = 2 : The feature is enabled but dynamically enabled at runtime 278 * depending on hardware capability. 279 * 280 * For better readability, state values are defined with macros, namely: 281 * { FEAT_STATE_DISABLED, FEAT_STATE_ALWAYS, FEAT_STATE_CHECK }, taking values 282 * { 0, 1, 2 }, respectively, as their naming. 283 **********************************************************************************/ 284 void detect_arch_features(void) 285 { 286 tainted = false; 287 288 /* v8.0 features */ 289 read_feat_sb(); 290 read_feat_csv2_2(); 291 292 /* v8.1 features */ 293 read_feat_pan(); 294 read_feat_vhe(); 295 296 /* v8.2 features */ 297 read_feat_ras(); 298 299 /* v8.3 features */ 300 read_feat_pauth(); 301 302 /* v8.4 features */ 303 read_feat_dit(); 304 check_feature(ENABLE_FEAT_AMUv1, read_feat_amu_id_field(), 305 "AMUv1", 1, 2); 306 read_feat_mpam(); 307 read_feat_nv2(); 308 read_feat_sel2(); 309 read_feat_trf(); 310 311 /* v8.5 features */ 312 read_feat_mte(); 313 read_feat_rng(); 314 read_feat_bti(); 315 read_feat_rng_trap(); 316 317 /* v8.6 features */ 318 read_feat_amuv1p1(); 319 check_feature(ENABLE_FEAT_FGT, read_feat_fgt_id_field(), "FGT", 1, 1); 320 read_feat_ecv(); 321 read_feat_twed(); 322 323 /* v8.7 features */ 324 check_feature(ENABLE_FEAT_HCX, read_feat_hcx_id_field(), "HCX", 1, 1); 325 326 /* v9.0 features */ 327 check_feature(ENABLE_BRBE_FOR_NS, read_feat_brbe_id_field(), 328 "BRBE", 1, 2); 329 check_feature(ENABLE_TRBE_FOR_NS, read_feat_trbe_id_field(), 330 "TRBE", 1, 1); 331 332 /* v9.2 features */ 333 read_feat_rme(); 334 335 if (tainted) { 336 panic(); 337 } 338 } 339