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. 40 * Panics if a feature is forcefully enabled, but not available on the PE. 41 * 42 * We force inlining here to let the compiler optimise away the whole check 43 * if the feature is disabled at build time (FEAT_STATE_DISABLED). 44 ******************************************************************************/ 45 static inline void __attribute((__always_inline__)) 46 check_feature(int state, unsigned long field, const char *feat_name) 47 { 48 if (state == FEAT_STATE_ALWAYS && field == 0U) { 49 ERROR("FEAT_%s not supported by the PE\n", feat_name); 50 tainted = true; 51 } 52 } 53 54 /****************************************** 55 * Feature : FEAT_SB (Speculation Barrier) 56 *****************************************/ 57 static void read_feat_sb(void) 58 { 59 #if (ENABLE_FEAT_SB == FEAT_STATE_ALWAYS) 60 feat_detect_panic(is_armv8_0_feat_sb_present(), "SB"); 61 #endif 62 } 63 64 /****************************************************** 65 * Feature : FEAT_CSV2_2 (Cache Speculation Variant 2) 66 *****************************************************/ 67 static void read_feat_csv2_2(void) 68 { 69 #if (ENABLE_FEAT_CSV2_2 == FEAT_STATE_ALWAYS) 70 feat_detect_panic(is_armv8_0_feat_csv2_2_present(), "CSV2_2"); 71 #endif 72 } 73 74 /*********************************************** 75 * Feature : FEAT_PAN (Privileged Access Never) 76 **********************************************/ 77 static void read_feat_pan(void) 78 { 79 #if (ENABLE_FEAT_PAN == FEAT_STATE_ALWAYS) 80 feat_detect_panic(is_armv8_1_pan_present(), "PAN"); 81 #endif 82 } 83 84 /****************************************************** 85 * Feature : FEAT_VHE (Virtualization Host Extensions) 86 *****************************************************/ 87 static void read_feat_vhe(void) 88 { 89 #if (ENABLE_FEAT_VHE == FEAT_STATE_ALWAYS) 90 feat_detect_panic(is_armv8_1_vhe_present(), "VHE"); 91 #endif 92 } 93 94 /******************************************************************************* 95 * Feature : FEAT_RAS (Reliability, Availability, and Serviceability Extension) 96 ******************************************************************************/ 97 static void read_feat_ras(void) 98 { 99 #if (RAS_EXTENSION == FEAT_STATE_ALWAYS) 100 feat_detect_panic(is_armv8_2_feat_ras_present(), "RAS"); 101 #endif 102 } 103 104 /************************************************ 105 * Feature : FEAT_PAUTH (Pointer Authentication) 106 ***********************************************/ 107 static void read_feat_pauth(void) 108 { 109 #if (ENABLE_PAUTH == FEAT_STATE_ALWAYS) || (CTX_INCLUDE_PAUTH_REGS == FEAT_STATE_ALWAYS) 110 feat_detect_panic(is_armv8_3_pauth_present(), "PAUTH"); 111 #endif 112 } 113 114 /************************************************************ 115 * Feature : FEAT_DIT (Data Independent Timing Instructions) 116 ***********************************************************/ 117 static void read_feat_dit(void) 118 { 119 #if (ENABLE_FEAT_DIT == FEAT_STATE_ALWAYS) 120 feat_detect_panic(is_armv8_4_feat_dit_present(), "DIT"); 121 #endif 122 } 123 124 /**************************************************************************** 125 * Feature : FEAT_MPAM (Memory Partitioning and Monitoring (MPAM) Extension) 126 ***************************************************************************/ 127 static void read_feat_mpam(void) 128 { 129 #if (ENABLE_MPAM_FOR_LOWER_ELS == FEAT_STATE_ALWAYS) 130 feat_detect_panic(get_mpam_version() != 0U, "MPAM"); 131 #endif 132 } 133 134 /************************************************************** 135 * Feature : FEAT_NV2 (Enhanced Nested Virtualization Support) 136 *************************************************************/ 137 static void read_feat_nv2(void) 138 { 139 #if (CTX_INCLUDE_NEVE_REGS == FEAT_STATE_ALWAYS) 140 unsigned int nv = get_armv8_4_feat_nv_support(); 141 142 feat_detect_panic((nv == ID_AA64MMFR2_EL1_NV2_SUPPORTED), "NV2"); 143 #endif 144 } 145 146 /*********************************** 147 * Feature : FEAT_SEL2 (Secure EL2) 148 **********************************/ 149 static void read_feat_sel2(void) 150 { 151 #if (ENABLE_FEAT_SEL2 == FEAT_STATE_ALWAYS) 152 feat_detect_panic(is_armv8_4_sel2_present(), "SEL2"); 153 #endif 154 } 155 156 /**************************************************** 157 * Feature : FEAT_TRF (Self-hosted Trace Extensions) 158 ***************************************************/ 159 static void read_feat_trf(void) 160 { 161 #if (ENABLE_TRF_FOR_NS == FEAT_STATE_ALWAYS) 162 feat_detect_panic(is_arm8_4_feat_trf_present(), "TRF"); 163 #endif 164 } 165 166 /************************************************ 167 * Feature : FEAT_MTE (Memory Tagging Extension) 168 ***********************************************/ 169 static void read_feat_mte(void) 170 { 171 #if (CTX_INCLUDE_MTE_REGS == FEAT_STATE_ALWAYS) 172 unsigned int mte = get_armv8_5_mte_support(); 173 174 feat_detect_panic((mte != MTE_UNIMPLEMENTED), "MTE"); 175 #endif 176 } 177 178 /*********************************************** 179 * Feature : FEAT_RNG (Random Number Generator) 180 **********************************************/ 181 static void read_feat_rng(void) 182 { 183 #if (ENABLE_FEAT_RNG == FEAT_STATE_ALWAYS) 184 feat_detect_panic(is_armv8_5_rng_present(), "RNG"); 185 #endif 186 } 187 188 /**************************************************** 189 * Feature : FEAT_BTI (Branch Target Identification) 190 ***************************************************/ 191 static void read_feat_bti(void) 192 { 193 #if (ENABLE_BTI == FEAT_STATE_ALWAYS) 194 feat_detect_panic(is_armv8_5_bti_present(), "BTI"); 195 #endif 196 } 197 198 /*********************************************** 199 * Feature : FEAT_AMUv1p1 (AMU Extensions v1.1) 200 **********************************************/ 201 static void read_feat_amuv1p1(void) 202 { 203 #if (ENABLE_FEAT_AMUv1p1 == FEAT_STATE_ALWAYS) 204 feat_detect_panic(is_armv8_6_feat_amuv1p1_present(), "AMUv1p1"); 205 #endif 206 } 207 208 /******************************************************* 209 * Feature : FEAT_ECV (Enhanced Counter Virtualization) 210 ******************************************************/ 211 static void read_feat_ecv(void) 212 { 213 #if (ENABLE_FEAT_ECV == FEAT_STATE_ALWAYS) 214 unsigned int ecv = get_armv8_6_ecv_support(); 215 216 feat_detect_panic(((ecv == ID_AA64MMFR0_EL1_ECV_SUPPORTED) || 217 (ecv == ID_AA64MMFR0_EL1_ECV_SELF_SYNCH)), "ECV"); 218 #endif 219 } 220 221 /*********************************************************** 222 * Feature : FEAT_TWED (Delayed Trapping of WFE Instruction) 223 **********************************************************/ 224 static void read_feat_twed(void) 225 { 226 #if (ENABLE_FEAT_TWED == FEAT_STATE_ALWAYS) 227 feat_detect_panic(is_armv8_6_twed_present(), "TWED"); 228 #endif 229 } 230 231 /****************************************************************** 232 * Feature : FEAT_HCX (Extended Hypervisor Configuration Register) 233 *****************************************************************/ 234 static void read_feat_hcx(void) 235 { 236 #if (ENABLE_FEAT_HCX == FEAT_STATE_ALWAYS) 237 feat_detect_panic(is_feat_hcx_present(), "HCX"); 238 #endif 239 } 240 241 /************************************************** 242 * Feature : FEAT_RME (Realm Management Extension) 243 *************************************************/ 244 static void read_feat_rme(void) 245 { 246 #if (ENABLE_RME == FEAT_STATE_ALWAYS) 247 feat_detect_panic((get_armv9_2_feat_rme_support() != 248 ID_AA64PFR0_FEAT_RME_NOT_SUPPORTED), "RME"); 249 #endif 250 } 251 252 /****************************************************** 253 * Feature : FEAT_BRBE (Branch Record Buffer Extension) 254 *****************************************************/ 255 static void read_feat_brbe(void) 256 { 257 #if (ENABLE_BRBE_FOR_NS == FEAT_STATE_ALWAYS) 258 feat_detect_panic(is_feat_brbe_present(), "BRBE"); 259 #endif 260 } 261 262 /****************************************************** 263 * Feature : FEAT_TRBE (Trace Buffer Extension) 264 *****************************************************/ 265 static void read_feat_trbe(void) 266 { 267 #if (ENABLE_TRBE_FOR_NS == FEAT_STATE_ALWAYS) 268 feat_detect_panic(is_feat_trbe_present(), "TRBE"); 269 #endif 270 } 271 272 /****************************************************************** 273 * Feature : FEAT_RNG_TRAP (Trapping support for RNDR/RNDRRS) 274 *****************************************************************/ 275 static void read_feat_rng_trap(void) 276 { 277 #if (ENABLE_FEAT_RNG_TRAP == FEAT_STATE_ALWAYS) 278 feat_detect_panic(is_feat_rng_trap_present(), "RNG_TRAP"); 279 #endif 280 } 281 282 /*********************************************************************************** 283 * TF-A supports many Arm architectural features starting from arch version 284 * (8.0 till 8.7+). These features are mostly enabled through build flags. This 285 * mechanism helps in validating these build flags in the early boot phase 286 * either in BL1 or BL31 depending on the platform and assists in identifying 287 * and notifying the features which are enabled but not supported by the PE. 288 * 289 * It reads all the enabled features ID-registers and ensures the features 290 * are supported by the PE. 291 * In case if they aren't it stops booting at an early phase and logs the error 292 * messages, notifying the platforms about the features that are not supported. 293 * 294 * Further the procedure is implemented with a tri-state approach for each feature: 295 * ENABLE_FEAT_xxx = 0 : The feature is disabled statically at compile time 296 * ENABLE_FEAT_xxx = 1 : The feature is enabled and must be present in hardware. 297 * There will be panic if feature is not present at cold boot. 298 * ENABLE_FEAT_xxx = 2 : The feature is enabled but dynamically enabled at runtime 299 * depending on hardware capability. 300 * 301 * For better readability, state values are defined with macros, namely: 302 * { FEAT_STATE_DISABLED, FEAT_STATE_ALWAYS, FEAT_STATE_CHECK }, taking values 303 * { 0, 1, 2 }, respectively, as their naming. 304 **********************************************************************************/ 305 void detect_arch_features(void) 306 { 307 tainted = false; 308 309 /* v8.0 features */ 310 read_feat_sb(); 311 read_feat_csv2_2(); 312 313 /* v8.1 features */ 314 read_feat_pan(); 315 read_feat_vhe(); 316 317 /* v8.2 features */ 318 read_feat_ras(); 319 320 /* v8.3 features */ 321 read_feat_pauth(); 322 323 /* v8.4 features */ 324 read_feat_dit(); 325 check_feature(ENABLE_FEAT_AMUv1, read_feat_amu_id_field(), "AMUv1"); 326 read_feat_mpam(); 327 read_feat_nv2(); 328 read_feat_sel2(); 329 read_feat_trf(); 330 331 /* v8.5 features */ 332 read_feat_mte(); 333 read_feat_rng(); 334 read_feat_bti(); 335 read_feat_rng_trap(); 336 337 /* v8.6 features */ 338 read_feat_amuv1p1(); 339 check_feature(ENABLE_FEAT_FGT, read_feat_fgt_id_field(), "FGT"); 340 read_feat_ecv(); 341 read_feat_twed(); 342 343 /* v8.7 features */ 344 read_feat_hcx(); 345 346 /* v9.0 features */ 347 read_feat_brbe(); 348 read_feat_trbe(); 349 350 /* v9.2 features */ 351 read_feat_rme(); 352 353 if (tainted) { 354 panic(); 355 } 356 } 357