1Arm CPU Specific Build Macros 2============================= 3 4This document describes the various build options present in the CPU specific 5operations framework to enable errata workarounds and to enable optimizations 6for a specific CPU on a platform. 7 8Security Vulnerability Workarounds 9---------------------------------- 10 11TF-A exports a series of build flags which control which security 12vulnerability workarounds should be applied at runtime. 13 14- ``WORKAROUND_CVE_2017_5715``: Enables the security workaround for 15 `CVE-2017-5715`_. This flag can be set to 0 by the platform if none 16 of the PEs in the system need the workaround. Setting this flag to 0 provides 17 no performance benefit for non-affected platforms, it just helps to comply 18 with the recommendation in the spec regarding workaround discovery. 19 Defaults to 1. 20 21- ``WORKAROUND_CVE_2018_3639``: Enables the security workaround for 22 `CVE-2018-3639`_. Defaults to 1. The TF-A project recommends to keep 23 the default value of 1 even on platforms that are unaffected by 24 CVE-2018-3639, in order to comply with the recommendation in the spec 25 regarding workaround discovery. 26 27- ``DYNAMIC_WORKAROUND_CVE_2018_3639``: Enables dynamic mitigation for 28 `CVE-2018-3639`_. This build option should be set to 1 if the target 29 platform contains at least 1 CPU that requires dynamic mitigation. 30 Defaults to 0. 31 32- ``WORKAROUND_CVE_2022_23960``: Enables mitigation for `CVE-2022-23960`_. 33 This build option should be set to 1 if the target platform contains at 34 least 1 CPU that requires this mitigation. Defaults to 1. 35 36.. _arm_cpu_macros_errata_workarounds: 37 38CPU Errata Workarounds 39---------------------- 40 41TF-A exports a series of build flags which control the errata workarounds that 42are applied to each CPU by the reset handler. The errata details can be found 43in the CPU specific errata documents published by Arm: 44 45- `Cortex-A53 MPCore Software Developers Errata Notice`_ 46- `Cortex-A57 MPCore Software Developers Errata Notice`_ 47- `Cortex-A72 MPCore Software Developers Errata Notice`_ 48 49The errata workarounds are implemented for a particular revision or a set of 50processor revisions. This is checked by the reset handler at runtime. Each 51errata workaround is identified by its ``ID`` as specified in the processor's 52errata notice document. The format of the define used to enable/disable the 53errata workaround is ``ERRATA_<Processor name>_<ID>``, where the ``Processor name`` 54is for example ``A57`` for the ``Cortex_A57`` CPU. 55 56Refer to :ref:`firmware_design_cpu_errata_reporting` for information on how to 57write errata workaround functions. 58 59All workarounds are disabled by default. The platform is responsible for 60enabling these workarounds according to its requirement by defining the 61errata workaround build flags in the platform specific makefile. In case 62these workarounds are enabled for the wrong CPU revision then the errata 63workaround is not applied. In the DEBUG build, this is indicated by 64printing a warning to the crash console. 65 66In the current implementation, a platform which has more than 1 variant 67with different revisions of a processor has no runtime mechanism available 68for it to specify which errata workarounds should be enabled or not. 69 70The value of the build flags is 0 by default, that is, disabled. A value of 1 71will enable it. 72 73For Cortex-A9, the following errata build flags are defined : 74 75- ``ERRATA_A9_794073``: This applies errata 794073 workaround to Cortex-A9 76 CPU. This needs to be enabled for all revisions of the CPU. 77 78For Cortex-A15, the following errata build flags are defined : 79 80- ``ERRATA_A15_816470``: This applies errata 816470 workaround to Cortex-A15 81 CPU. This needs to be enabled only for revision >= r3p0 of the CPU. 82 83- ``ERRATA_A15_827671``: This applies errata 827671 workaround to Cortex-A15 84 CPU. This needs to be enabled only for revision >= r3p0 of the CPU. 85 86For Cortex-A17, the following errata build flags are defined : 87 88- ``ERRATA_A17_852421``: This applies errata 852421 workaround to Cortex-A17 89 CPU. This needs to be enabled only for revision <= r1p2 of the CPU. 90 91- ``ERRATA_A17_852423``: This applies errata 852423 workaround to Cortex-A17 92 CPU. This needs to be enabled only for revision <= r1p2 of the CPU. 93 94For Cortex-A35, the following errata build flags are defined : 95 96- ``ERRATA_A35_855472``: This applies errata 855472 workaround to Cortex-A35 97 CPUs. This needs to be enabled only for revision r0p0 of Cortex-A35. 98 99For Cortex-A53, the following errata build flags are defined : 100 101- ``ERRATA_A53_819472``: This applies errata 819472 workaround to all 102 CPUs. This needs to be enabled only for revision <= r0p1 of Cortex-A53. 103 104- ``ERRATA_A53_824069``: This applies errata 824069 workaround to all 105 CPUs. This needs to be enabled only for revision <= r0p2 of Cortex-A53. 106 107- ``ERRATA_A53_826319``: This applies errata 826319 workaround to Cortex-A53 108 CPU. This needs to be enabled only for revision <= r0p2 of the CPU. 109 110- ``ERRATA_A53_827319``: This applies errata 827319 workaround to all 111 CPUs. This needs to be enabled only for revision <= r0p2 of Cortex-A53. 112 113- ``ERRATA_A53_835769``: This applies erratum 835769 workaround at compile and 114 link time to Cortex-A53 CPU. This needs to be enabled for some variants of 115 revision <= r0p4. This workaround can lead the linker to create ``*.stub`` 116 sections. 117 118- ``ERRATA_A53_836870``: This applies errata 836870 workaround to Cortex-A53 119 CPU. This needs to be enabled only for revision <= r0p3 of the CPU. From 120 r0p4 and onwards, this errata is enabled by default in hardware. 121 122- ``ERRATA_A53_843419``: This applies erratum 843419 workaround at link time 123 to Cortex-A53 CPU. This needs to be enabled for some variants of revision 124 <= r0p4. This workaround can lead the linker to emit ``*.stub`` sections 125 which are 4kB aligned. 126 127- ``ERRATA_A53_855873``: This applies errata 855873 workaround to Cortex-A53 128 CPUs. Though the erratum is present in every revision of the CPU, 129 this workaround is only applied to CPUs from r0p3 onwards, which feature 130 a chicken bit in CPUACTLR_EL1 to enable a hardware workaround. 131 Earlier revisions of the CPU have other errata which require the same 132 workaround in software, so they should be covered anyway. 133 134- ``ERRATA_A53_1530924``: This applies errata 1530924 workaround to all 135 revisions of Cortex-A53 CPU. 136 137For Cortex-A55, the following errata build flags are defined : 138 139- ``ERRATA_A55_768277``: This applies errata 768277 workaround to Cortex-A55 140 CPU. This needs to be enabled only for revision r0p0 of the CPU. 141 142- ``ERRATA_A55_778703``: This applies errata 778703 workaround to Cortex-A55 143 CPU. This needs to be enabled only for revision r0p0 of the CPU. 144 145- ``ERRATA_A55_798797``: This applies errata 798797 workaround to Cortex-A55 146 CPU. This needs to be enabled only for revision r0p0 of the CPU. 147 148- ``ERRATA_A55_846532``: This applies errata 846532 workaround to Cortex-A55 149 CPU. This needs to be enabled only for revision <= r0p1 of the CPU. 150 151- ``ERRATA_A55_903758``: This applies errata 903758 workaround to Cortex-A55 152 CPU. This needs to be enabled only for revision <= r0p1 of the CPU. 153 154- ``ERRATA_A55_1221012``: This applies errata 1221012 workaround to Cortex-A55 155 CPU. This needs to be enabled only for revision <= r1p0 of the CPU. 156 157- ``ERRATA_A55_1530923``: This applies errata 1530923 workaround to all 158 revisions of Cortex-A55 CPU. 159 160For Cortex-A57, the following errata build flags are defined : 161 162- ``ERRATA_A57_806969``: This applies errata 806969 workaround to Cortex-A57 163 CPU. This needs to be enabled only for revision r0p0 of the CPU. 164 165- ``ERRATA_A57_813419``: This applies errata 813419 workaround to Cortex-A57 166 CPU. This needs to be enabled only for revision r0p0 of the CPU. 167 168- ``ERRATA_A57_813420``: This applies errata 813420 workaround to Cortex-A57 169 CPU. This needs to be enabled only for revision r0p0 of the CPU. 170 171- ``ERRATA_A57_814670``: This applies errata 814670 workaround to Cortex-A57 172 CPU. This needs to be enabled only for revision r0p0 of the CPU. 173 174- ``ERRATA_A57_817169``: This applies errata 817169 workaround to Cortex-A57 175 CPU. This needs to be enabled only for revision <= r0p1 of the CPU. 176 177- ``ERRATA_A57_826974``: This applies errata 826974 workaround to Cortex-A57 178 CPU. This needs to be enabled only for revision <= r1p1 of the CPU. 179 180- ``ERRATA_A57_826977``: This applies errata 826977 workaround to Cortex-A57 181 CPU. This needs to be enabled only for revision <= r1p1 of the CPU. 182 183- ``ERRATA_A57_828024``: This applies errata 828024 workaround to Cortex-A57 184 CPU. This needs to be enabled only for revision <= r1p1 of the CPU. 185 186- ``ERRATA_A57_829520``: This applies errata 829520 workaround to Cortex-A57 187 CPU. This needs to be enabled only for revision <= r1p2 of the CPU. 188 189- ``ERRATA_A57_833471``: This applies errata 833471 workaround to Cortex-A57 190 CPU. This needs to be enabled only for revision <= r1p2 of the CPU. 191 192- ``ERRATA_A57_859972``: This applies errata 859972 workaround to Cortex-A57 193 CPU. This needs to be enabled only for revision <= r1p3 of the CPU. 194 195- ``ERRATA_A57_1319537``: This applies errata 1319537 workaround to all 196 revisions of Cortex-A57 CPU. 197 198For Cortex-A72, the following errata build flags are defined : 199 200- ``ERRATA_A72_859971``: This applies errata 859971 workaround to Cortex-A72 201 CPU. This needs to be enabled only for revision <= r0p3 of the CPU. 202 203- ``ERRATA_A72_1319367``: This applies errata 1319367 workaround to all 204 revisions of Cortex-A72 CPU. 205 206For Cortex-A73, the following errata build flags are defined : 207 208- ``ERRATA_A73_852427``: This applies errata 852427 workaround to Cortex-A73 209 CPU. This needs to be enabled only for revision r0p0 of the CPU. 210 211- ``ERRATA_A73_855423``: This applies errata 855423 workaround to Cortex-A73 212 CPU. This needs to be enabled only for revision <= r0p1 of the CPU. 213 214For Cortex-A75, the following errata build flags are defined : 215 216- ``ERRATA_A75_764081``: This applies errata 764081 workaround to Cortex-A75 217 CPU. This needs to be enabled only for revision r0p0 of the CPU. 218 219- ``ERRATA_A75_790748``: This applies errata 790748 workaround to Cortex-A75 220 CPU. This needs to be enabled only for revision r0p0 of the CPU. 221 222For Cortex-A76, the following errata build flags are defined : 223 224- ``ERRATA_A76_1073348``: This applies errata 1073348 workaround to Cortex-A76 225 CPU. This needs to be enabled only for revision <= r1p0 of the CPU. 226 227- ``ERRATA_A76_1130799``: This applies errata 1130799 workaround to Cortex-A76 228 CPU. This needs to be enabled only for revision <= r2p0 of the CPU. 229 230- ``ERRATA_A76_1220197``: This applies errata 1220197 workaround to Cortex-A76 231 CPU. This needs to be enabled only for revision <= r2p0 of the CPU. 232 233- ``ERRATA_A76_1257314``: This applies errata 1257314 workaround to Cortex-A76 234 CPU. This needs to be enabled only for revision <= r3p0 of the CPU. 235 236- ``ERRATA_A76_1262606``: This applies errata 1262606 workaround to Cortex-A76 237 CPU. This needs to be enabled only for revision <= r3p0 of the CPU. 238 239- ``ERRATA_A76_1262888``: This applies errata 1262888 workaround to Cortex-A76 240 CPU. This needs to be enabled only for revision <= r3p0 of the CPU. 241 242- ``ERRATA_A76_1275112``: This applies errata 1275112 workaround to Cortex-A76 243 CPU. This needs to be enabled only for revision <= r3p0 of the CPU. 244 245- ``ERRATA_A76_1791580``: This applies errata 1791580 workaround to Cortex-A76 246 CPU. This needs to be enabled only for revision <= r4p0 of the CPU. 247 248- ``ERRATA_A76_1165522``: This applies errata 1165522 workaround to all 249 revisions of Cortex-A76 CPU. This errata is fixed in r3p0 but due to 250 limitation of errata framework this errata is applied to all revisions 251 of Cortex-A76 CPU. 252 253- ``ERRATA_A76_1868343``: This applies errata 1868343 workaround to Cortex-A76 254 CPU. This needs to be enabled only for revision <= r4p0 of the CPU. 255 256- ``ERRATA_A76_1946160``: This applies errata 1946160 workaround to Cortex-A76 257 CPU. This needs to be enabled only for revisions r3p0 - r4p1 of the CPU. 258 259For Cortex-A77, the following errata build flags are defined : 260 261- ``ERRATA_A77_1508412``: This applies errata 1508412 workaround to Cortex-A77 262 CPU. This needs to be enabled only for revision <= r1p0 of the CPU. 263 264- ``ERRATA_A77_1925769``: This applies errata 1925769 workaround to Cortex-A77 265 CPU. This needs to be enabled only for revision <= r1p1 of the CPU. 266 267- ``ERRATA_A77_1946167``: This applies errata 1946167 workaround to Cortex-A77 268 CPU. This needs to be enabled only for revision <= r1p1 of the CPU. 269 270- ``ERRATA_A77_1791578``: This applies errata 1791578 workaround to Cortex-A77 271 CPU. This needs to be enabled for r0p0, r1p0, and r1p1, it is still open. 272 273For Cortex-A78, the following errata build flags are defined : 274 275- ``ERRATA_A78_1688305``: This applies errata 1688305 workaround to Cortex-A78 276 CPU. This needs to be enabled only for revision r0p0 - r1p0 of the CPU. 277 278- ``ERRATA_A78_1941498``: This applies errata 1941498 workaround to Cortex-A78 279 CPU. This needs to be enabled for revisions r0p0, r1p0, and r1p1 of the CPU. 280 281- ``ERRATA_A78_1951500``: This applies errata 1951500 workaround to Cortex-A78 282 CPU. This needs to be enabled for revisions r1p0 and r1p1, r0p0 has the same 283 issue but there is no workaround for that revision. 284 285- ``ERRATA_A78_1821534``: This applies errata 1821534 workaround to Cortex-A78 286 CPU. This needs to be enabled for revisions r0p0 and r1p0. 287 288- ``ERRATA_A78_1952683``: This applies errata 1952683 workaround to Cortex-A78 289 CPU. This needs to be enabled for revision r0p0, it is fixed in r1p0. 290 291- ``ERRATA_A78_2132060``: This applies errata 2132060 workaround to Cortex-A78 292 CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1, and r1p2. It 293 is still open. 294 295- ``ERRATA_A78_2242635``: This applies errata 2242635 workaround to Cortex-A78 296 CPU. This needs to be enabled for revisions r1p0, r1p1, and r1p2. The issue 297 is present in r0p0 but there is no workaround. It is still open. 298 299- ``ERRATA_A78_2376745``: This applies errata 2376745 workaround to Cortex-A78 300 CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1, and r1p2, and 301 it is still open. 302 303- ``ERRATA_A78_2395406``: This applies errata 2395406 workaround to Cortex-A78 304 CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1, and r1p2, and 305 it is still open. 306 307For Cortex-A78 AE, the following errata build flags are defined : 308 309- ``ERRATA_A78_AE_1941500`` : This applies errata 1941500 workaround to 310 Cortex-A78 AE CPU. This needs to be enabled for revisions r0p0 and r0p1. 311 This erratum is still open. 312 313- ``ERRATA_A78_AE_1951502`` : This applies errata 1951502 workaround to 314 Cortex-A78 AE CPU. This needs to be enabled for revisions r0p0 and r0p1. This 315 erratum is still open. 316 317- ``ERRATA_A78_AE_2376748`` : This applies errata 2376748 workaround to 318 Cortex-A78 AE CPU. This needs to be enabled for revisions r0p0 and r0p1. This 319 erratum is still open. 320 321- ``ERRATA_A78_AE_2395408`` : This applies errata 2395408 workaround to 322 Cortex-A78 AE CPU. This needs to be enabled for revisions r0p0 and r0p1. This 323 erratum is still open. 324 325For Neoverse N1, the following errata build flags are defined : 326 327- ``ERRATA_N1_1073348``: This applies errata 1073348 workaround to Neoverse-N1 328 CPU. This needs to be enabled only for revision r0p0 and r1p0 of the CPU. 329 330- ``ERRATA_N1_1130799``: This applies errata 1130799 workaround to Neoverse-N1 331 CPU. This needs to be enabled only for revision <= r2p0 of the CPU. 332 333- ``ERRATA_N1_1165347``: This applies errata 1165347 workaround to Neoverse-N1 334 CPU. This needs to be enabled only for revision <= r2p0 of the CPU. 335 336- ``ERRATA_N1_1207823``: This applies errata 1207823 workaround to Neoverse-N1 337 CPU. This needs to be enabled only for revision <= r2p0 of the CPU. 338 339- ``ERRATA_N1_1220197``: This applies errata 1220197 workaround to Neoverse-N1 340 CPU. This needs to be enabled only for revision <= r2p0 of the CPU. 341 342- ``ERRATA_N1_1257314``: This applies errata 1257314 workaround to Neoverse-N1 343 CPU. This needs to be enabled only for revision <= r3p0 of the CPU. 344 345- ``ERRATA_N1_1262606``: This applies errata 1262606 workaround to Neoverse-N1 346 CPU. This needs to be enabled only for revision <= r3p0 of the CPU. 347 348- ``ERRATA_N1_1262888``: This applies errata 1262888 workaround to Neoverse-N1 349 CPU. This needs to be enabled only for revision <= r3p0 of the CPU. 350 351- ``ERRATA_N1_1275112``: This applies errata 1275112 workaround to Neoverse-N1 352 CPU. This needs to be enabled only for revision <= r3p0 of the CPU. 353 354- ``ERRATA_N1_1315703``: This applies errata 1315703 workaround to Neoverse-N1 355 CPU. This needs to be enabled only for revision <= r3p0 of the CPU. 356 357- ``ERRATA_N1_1542419``: This applies errata 1542419 workaround to Neoverse-N1 358 CPU. This needs to be enabled only for revisions r3p0 - r4p0 of the CPU. 359 360- ``ERRATA_N1_1868343``: This applies errata 1868343 workaround to Neoverse-N1 361 CPU. This needs to be enabled only for revision <= r4p0 of the CPU. 362 363- ``ERRATA_N1_1946160``: This applies errata 1946160 workaround to Neoverse-N1 364 CPU. This needs to be enabled for revisions r3p0, r3p1, r4p0, and r4p1, for 365 revisions r0p0, r1p0, and r2p0 there is no workaround. 366 367For Neoverse V1, the following errata build flags are defined : 368 369- ``ERRATA_V1_1774420``: This applies errata 1774420 workaround to Neoverse-V1 370 CPU. This needs to be enabled only for revisions r0p0 and r1p0, it is fixed 371 in r1p1. 372 373- ``ERRATA_V1_1791573``: This applies errata 1791573 workaround to Neoverse-V1 374 CPU. This needs to be enabled only for revisions r0p0 and r1p0, it is fixed 375 in r1p1. 376 377- ``ERRATA_V1_1852267``: This applies errata 1852267 workaround to Neoverse-V1 378 CPU. This needs to be enabled only for revisions r0p0 and r1p0, it is fixed 379 in r1p1. 380 381- ``ERRATA_V1_1925756``: This applies errata 1925756 workaround to Neoverse-V1 382 CPU. This needs to be enabled for r0p0, r1p0, and r1p1, it is still open. 383 384- ``ERRATA_V1_1940577``: This applies errata 1940577 workaround to Neoverse-V1 385 CPU. This needs to be enabled only for revision r1p0 and r1p1 of the 386 CPU. 387 388- ``ERRATA_V1_1966096``: This applies errata 1966096 workaround to Neoverse-V1 389 CPU. This needs to be enabled for revisions r1p0 and r1p1 of the CPU, the 390 issue is present in r0p0 as well but there is no workaround for that 391 revision. It is still open. 392 393- ``ERRATA_V1_2139242``: This applies errata 2139242 workaround to Neoverse-V1 394 CPU. This needs to be enabled for revisions r0p0, r1p0, and r1p1 of the 395 CPU. It is still open. 396 397- ``ERRATA_V1_2108267``: This applies errata 2108267 workaround to Neoverse-V1 398 CPU. This needs to be enabled for revisions r0p0, r1p0, and r1p1 of the CPU. 399 It is still open. 400 401- ``ERRATA_V1_2216392``: This applies errata 2216392 workaround to Neoverse-V1 402 CPU. This needs to be enabled for revisions r1p0 and r1p1 of the CPU, the 403 issue is present in r0p0 as well but there is no workaround for that 404 revision. It is still open. 405 406For Cortex-A710, the following errata build flags are defined : 407 408- ``ERRATA_A710_1987031``: This applies errata 1987031 workaround to 409 Cortex-A710 CPU. This needs to be enabled only for revisions r0p0, r1p0 and 410 r2p0 of the CPU. It is still open. 411 412- ``ERRATA_A710_2081180``: This applies errata 2081180 workaround to 413 Cortex-A710 CPU. This needs to be enabled only for revisions r0p0, r1p0 and 414 r2p0 of the CPU. It is still open. 415 416- ``ERRATA_A710_2055002``: This applies errata 2055002 workaround to 417 Cortex-A710 CPU. This needs to be enabled for revisions r1p0, r2p0 of the CPU 418 and is still open. 419 420- ``ERRATA_A710_2017096``: This applies errata 2017096 workaround to 421 Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0 422 of the CPU and is still open. 423 424- ``ERRATA_A710_2083908``: This applies errata 2083908 workaround to 425 Cortex-A710 CPU. This needs to be enabled for revision r2p0 of the CPU and 426 is still open. 427 428- ``ERRATA_A710_2058056``: This applies errata 2058056 workaround to 429 Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0 430 of the CPU and is still open. 431 432- ``ERRATA_A710_2267065``: This applies errata 2267065 workaround to 433 Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0 434 of the CPU and is fixed in r2p1. 435 436- ``ERRATA_A710_2136059``: This applies errata 2136059 workaround to 437 Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0 438 of the CPU and is fixed in r2p1. 439 440- ``ERRATA_A710_2282622``: This applies errata 2282622 workaround to 441 Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0 442 of the CPU and is fixed in r2p1. 443 444For Neoverse N2, the following errata build flags are defined : 445 446- ``ERRATA_N2_2002655``: This applies errata 2002655 workaround to Neoverse-N2 447 CPU. This needs to be enabled for revision r0p0 of the CPU, it is still open. 448 449- ``ERRATA_N2_2067956``: This applies errata 2067956 workaround to Neoverse-N2 450 CPU. This needs to be enabled for revision r0p0 of the CPU and is still open. 451 452- ``ERRATA_N2_2025414``: This applies errata 2025414 workaround to Neoverse-N2 453 CPU. This needs to be enabled for revision r0p0 of the CPU and is still open. 454 455- ``ERRATA_N2_2189731``: This applies errata 2189731 workaround to Neoverse-N2 456 CPU. This needs to be enabled for revision r0p0 of the CPU and is still open. 457 458- ``ERRATA_N2_2138956``: This applies errata 2138956 workaround to Neoverse-N2 459 CPU. This needs to be enabled for revision r0p0 of the CPU and is still open. 460 461- ``ERRATA_N2_2138953``: This applies errata 2138953 workaround to Neoverse-N2 462 CPU. This needs to be enabled for revision r0p0 of the CPU and is still open. 463 464- ``ERRATA_N2_2242415``: This applies errata 2242415 workaround to Neoverse-N2 465 CPU. This needs to be enabled for revision r0p0 of the CPU and is still open. 466 467- ``ERRATA_N2_2138958``: This applies errata 2138958 workaround to Neoverse-N2 468 CPU. This needs to be enabled for revision r0p0 of the CPU and is still open. 469 470- ``ERRATA_N2_2242400``: This applies errata 2242400 workaround to Neoverse-N2 471 CPU. This needs to be enabled for revision r0p0 of the CPU and is still open. 472 473- ``ERRATA_N2_2280757``: This applies errata 2280757 workaround to Neoverse-N2 474 CPU. This needs to be enabled for revision r0p0 of the CPU and is still open. 475 476For Cortex-X2, the following errata build flags are defined : 477 478- ``ERRATA_X2_2002765``: This applies errata 2002765 workaround to Cortex-X2 479 CPU. This needs to be enabled for revisions r0p0, r1p0, and r2p0 of the CPU, 480 it is still open. 481 482- ``ERRATA_X2_2058056``: This applies errata 2058056 workaround to Cortex-X2 483 CPU. This needs to be enabled for revisions r0p0, r1p0, and r2p0 of the CPU, 484 it is still open. 485 486- ``ERRATA_X2_2083908``: This applies errata 2083908 workaround to Cortex-X2 487 CPU. This needs to be enabled for revision r2p0 of the CPU, it is still open. 488 489- ``ERRATA_X2_2017096``: This applies errata 2017096 workaround to 490 Cortex-X2 CPU. This needs to be enabled only for revisions r0p0, r1p0 and 491 r2p0 of the CPU, it is fixed in r2p1. 492 493- ``ERRATA_X2_2081180``: This applies errata 2081180 workaround to 494 Cortex-X2 CPU. This needs to be enabled only for revisions r0p0, r1p0 and 495 r2p0 of the CPU, it is fixed in r2p1. 496 497- ``ERRATA_X2_2216384``: This applies errata 2216384 workaround to 498 Cortex-X2 CPU. This needs to be enabled only for revisions r0p0, r1p0 and 499 r2p0 of the CPU, it is fixed in r2p1. 500 501- ``ERRATA_X2_2147715``: This applies errata 2147715 workaround to 502 Cortex-X2 CPU. This needs to be enabled only for revision r2p0 of the CPU, 503 it is fixed in r2p1. 504 505For Cortex-A510, the following errata build flags are defined : 506 507- ``ERRATA_A510_1922240``: This applies errata 1922240 workaround to 508 Cortex-A510 CPU. This needs to be enabled only for revision r0p0, it is 509 fixed in r0p1. 510 511- ``ERRATA_A510_2288014``: This applies errata 2288014 workaround to 512 Cortex-A510 CPU. This needs to be enabled only for revisions r0p0, r0p1, 513 r0p2, r0p3 and r1p0, it is fixed in r1p1. 514 515- ``ERRATA_A510_2042739``: This applies errata 2042739 workaround to 516 Cortex-A510 CPU. This needs to be enabled only for revisions r0p0, r0p1 and 517 r0p2, it is fixed in r0p3. 518 519- ``ERRATA_A510_2041909``: This applies errata 2041909 workaround to 520 Cortex-A510 CPU. This needs to be enabled only for revision r0p2 and is fixed 521 in r0p3. The issue is also present in r0p0 and r0p1 but there is no 522 workaround for those revisions. 523 524- ``ERRATA_A510_2250311``: This applies errata 2250311 workaround to 525 Cortex-A510 CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2, 526 r0p3 and r1p0, it is fixed in r1p1. This workaround disables MPMM even if 527 ENABLE_MPMM=1. 528 529- ``ERRATA_A510_2218950``: This applies errata 2218950 workaround to 530 Cortex-A510 CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2, 531 r0p3 and r1p0, it is fixed in r1p1. 532 533- ``ERRATA_A510_2172148``: This applies errata 2172148 workaround to 534 Cortex-A510 CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2, 535 r0p3 and r1p0, it is fixed in r1p1. 536 537DSU Errata Workarounds 538---------------------- 539 540Similar to CPU errata, TF-A also implements workarounds for DSU (DynamIQ 541Shared Unit) errata. The DSU errata details can be found in the respective Arm 542documentation: 543 544- `Arm DSU Software Developers Errata Notice`_. 545 546Each erratum is identified by an ``ID``, as defined in the DSU errata notice 547document. Thus, the build flags which enable/disable the errata workarounds 548have the format ``ERRATA_DSU_<ID>``. The implementation and application logic 549of DSU errata workarounds are similar to `CPU errata workarounds`_. 550 551For DSU errata, the following build flags are defined: 552 553- ``ERRATA_DSU_798953``: This applies errata 798953 workaround for the 554 affected DSU configurations. This errata applies only for those DSUs that 555 revision is r0p0 (on r0p1 it is fixed). However, please note that this 556 workaround results in increased DSU power consumption on idle. 557 558- ``ERRATA_DSU_936184``: This applies errata 936184 workaround for the 559 affected DSU configurations. This errata applies only for those DSUs that 560 contain the ACP interface **and** the DSU revision is older than r2p0 (on 561 r2p0 it is fixed). However, please note that this workaround results in 562 increased DSU power consumption on idle. 563 564CPU Specific optimizations 565-------------------------- 566 567This section describes some of the optimizations allowed by the CPU micro 568architecture that can be enabled by the platform as desired. 569 570- ``SKIP_A57_L1_FLUSH_PWR_DWN``: This flag enables an optimization in the 571 Cortex-A57 cluster power down sequence by not flushing the Level 1 data 572 cache. The L1 data cache and the L2 unified cache are inclusive. A flush 573 of the L2 by set/way flushes any dirty lines from the L1 as well. This 574 is a known safe deviation from the Cortex-A57 TRM defined power down 575 sequence. Each Cortex-A57 based platform must make its own decision on 576 whether to use the optimization. 577 578- ``A53_DISABLE_NON_TEMPORAL_HINT``: This flag disables the cache non-temporal 579 hint. The LDNP/STNP instructions as implemented on Cortex-A53 do not behave 580 in a way most programmers expect, and will most probably result in a 581 significant speed degradation to any code that employs them. The Armv8-A 582 architecture (see Arm DDI 0487A.h, section D3.4.3) allows cores to ignore 583 the non-temporal hint and treat LDNP/STNP as LDP/STP instead. Enabling this 584 flag enforces this behaviour. This needs to be enabled only for revisions 585 <= r0p3 of the CPU and is enabled by default. 586 587- ``A57_DISABLE_NON_TEMPORAL_HINT``: This flag has the same behaviour as 588 ``A53_DISABLE_NON_TEMPORAL_HINT`` but for Cortex-A57. This needs to be 589 enabled only for revisions <= r1p2 of the CPU and is enabled by default, 590 as recommended in section "4.7 Non-Temporal Loads/Stores" of the 591 `Cortex-A57 Software Optimization Guide`_. 592 593- ''A57_ENABLE_NON_CACHEABLE_LOAD_FWD'': This flag enables non-cacheable 594 streaming enhancement feature for Cortex-A57 CPUs. Platforms can set 595 this bit only if their memory system meets the requirement that cache 596 line fill requests from the Cortex-A57 processor are atomic. Each 597 Cortex-A57 based platform must make its own decision on whether to use 598 the optimization. This flag is disabled by default. 599 600- ``NEOVERSE_Nx_EXTERNAL_LLC``: This flag indicates that an external last 601 level cache(LLC) is present in the system, and that the DataSource field 602 on the master CHI interface indicates when data is returned from the LLC. 603 This is used to control how the LL_CACHE* PMU events count. 604 Default value is 0 (Disabled). 605 606-------------- 607 608*Copyright (c) 2014-2021, Arm Limited and Contributors. All rights reserved.* 609 610.. _CVE-2017-5715: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-5715 611.. _CVE-2018-3639: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-3639 612.. _CVE-2022-23960: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-23960 613.. _Cortex-A53 MPCore Software Developers Errata Notice: http://infocenter.arm.com/help/topic/com.arm.doc.epm048406/index.html 614.. _Cortex-A57 MPCore Software Developers Errata Notice: http://infocenter.arm.com/help/topic/com.arm.doc.epm049219/index.html 615.. _Cortex-A72 MPCore Software Developers Errata Notice: http://infocenter.arm.com/help/topic/com.arm.doc.epm012079/index.html 616.. _Cortex-A57 Software Optimization Guide: http://infocenter.arm.com/help/topic/com.arm.doc.uan0015b/Cortex_A57_Software_Optimization_Guide_external.pdf 617.. _Arm DSU Software Developers Errata Notice: http://infocenter.arm.com/help/topic/com.arm.doc.epm138168/index.html 618