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 303For Cortex-A78 AE, the following errata build flags are defined : 304 305- ``ERRATA_A78_AE_1941500`` : This applies errata 1941500 workaround to 306 Cortex-A78 AE CPU. This needs to be enabled for revisions r0p0 and r0p1. 307 This erratum is still open. 308 309- ``ERRATA_A78_AE_1951502`` : This applies errata 1951502 workaround to 310 Cortex-A78 AE CPU. This needs to be enabled for revisions r0p0 and r0p1. This 311 erratum is still open. 312 313- ``ERRATA_A78_AE_2376748`` : This applies errata 2376748 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_2395408`` : This applies errata 2395408 workaround to 318 Cortex-A78 AE CPU. This needs to be enabled for revisions r0p0 and r0p1. This 319 erratum is still open. 320 321For Neoverse N1, the following errata build flags are defined : 322 323- ``ERRATA_N1_1073348``: This applies errata 1073348 workaround to Neoverse-N1 324 CPU. This needs to be enabled only for revision r0p0 and r1p0 of the CPU. 325 326- ``ERRATA_N1_1130799``: This applies errata 1130799 workaround to Neoverse-N1 327 CPU. This needs to be enabled only for revision <= r2p0 of the CPU. 328 329- ``ERRATA_N1_1165347``: This applies errata 1165347 workaround to Neoverse-N1 330 CPU. This needs to be enabled only for revision <= r2p0 of the CPU. 331 332- ``ERRATA_N1_1207823``: This applies errata 1207823 workaround to Neoverse-N1 333 CPU. This needs to be enabled only for revision <= r2p0 of the CPU. 334 335- ``ERRATA_N1_1220197``: This applies errata 1220197 workaround to Neoverse-N1 336 CPU. This needs to be enabled only for revision <= r2p0 of the CPU. 337 338- ``ERRATA_N1_1257314``: This applies errata 1257314 workaround to Neoverse-N1 339 CPU. This needs to be enabled only for revision <= r3p0 of the CPU. 340 341- ``ERRATA_N1_1262606``: This applies errata 1262606 workaround to Neoverse-N1 342 CPU. This needs to be enabled only for revision <= r3p0 of the CPU. 343 344- ``ERRATA_N1_1262888``: This applies errata 1262888 workaround to Neoverse-N1 345 CPU. This needs to be enabled only for revision <= r3p0 of the CPU. 346 347- ``ERRATA_N1_1275112``: This applies errata 1275112 workaround to Neoverse-N1 348 CPU. This needs to be enabled only for revision <= r3p0 of the CPU. 349 350- ``ERRATA_N1_1315703``: This applies errata 1315703 workaround to Neoverse-N1 351 CPU. This needs to be enabled only for revision <= r3p0 of the CPU. 352 353- ``ERRATA_N1_1542419``: This applies errata 1542419 workaround to Neoverse-N1 354 CPU. This needs to be enabled only for revisions r3p0 - r4p0 of the CPU. 355 356- ``ERRATA_N1_1868343``: This applies errata 1868343 workaround to Neoverse-N1 357 CPU. This needs to be enabled only for revision <= r4p0 of the CPU. 358 359- ``ERRATA_N1_1946160``: This applies errata 1946160 workaround to Neoverse-N1 360 CPU. This needs to be enabled for revisions r3p0, r3p1, r4p0, and r4p1, for 361 revisions r0p0, r1p0, and r2p0 there is no workaround. 362 363For Neoverse V1, the following errata build flags are defined : 364 365- ``ERRATA_V1_1774420``: This applies errata 1774420 workaround to Neoverse-V1 366 CPU. This needs to be enabled only for revisions r0p0 and r1p0, it is fixed 367 in r1p1. 368 369- ``ERRATA_V1_1791573``: This applies errata 1791573 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_1852267``: This applies errata 1852267 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_1925756``: This applies errata 1925756 workaround to Neoverse-V1 378 CPU. This needs to be enabled for r0p0, r1p0, and r1p1, it is still open. 379 380- ``ERRATA_V1_1940577``: This applies errata 1940577 workaround to Neoverse-V1 381 CPU. This needs to be enabled only for revision r1p0 and r1p1 of the 382 CPU. 383 384- ``ERRATA_V1_1966096``: This applies errata 1966096 workaround to Neoverse-V1 385 CPU. This needs to be enabled for revisions r1p0 and r1p1 of the CPU, the 386 issue is present in r0p0 as well but there is no workaround for that 387 revision. It is still open. 388 389- ``ERRATA_V1_2139242``: This applies errata 2139242 workaround to Neoverse-V1 390 CPU. This needs to be enabled for revisions r0p0, r1p0, and r1p1 of the 391 CPU. It is still open. 392 393- ``ERRATA_V1_2108267``: This applies errata 2108267 workaround to Neoverse-V1 394 CPU. This needs to be enabled for revisions r0p0, r1p0, and r1p1 of the CPU. 395 It is still open. 396 397- ``ERRATA_V1_2216392``: This applies errata 2216392 workaround to Neoverse-V1 398 CPU. This needs to be enabled for revisions r1p0 and r1p1 of the CPU, the 399 issue is present in r0p0 as well but there is no workaround for that 400 revision. It is still open. 401 402For Cortex-A710, the following errata build flags are defined : 403 404- ``ERRATA_A710_1987031``: This applies errata 1987031 workaround to 405 Cortex-A710 CPU. This needs to be enabled only for revisions r0p0, r1p0 and 406 r2p0 of the CPU. It is still open. 407 408- ``ERRATA_A710_2081180``: This applies errata 2081180 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_2055002``: This applies errata 2055002 workaround to 413 Cortex-A710 CPU. This needs to be enabled for revisions r1p0, r2p0 of the CPU 414 and is still open. 415 416- ``ERRATA_A710_2017096``: This applies errata 2017096 workaround to 417 Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0 418 of the CPU and is still open. 419 420- ``ERRATA_A710_2083908``: This applies errata 2083908 workaround to 421 Cortex-A710 CPU. This needs to be enabled for revision r2p0 of the CPU and 422 is still open. 423 424- ``ERRATA_A710_2058056``: This applies errata 2058056 workaround to 425 Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0 426 of the CPU and is still open. 427 428- ``ERRATA_A710_2267065``: This applies errata 2267065 workaround to 429 Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0 430 of the CPU and is fixed in r2p1. 431 432- ``ERRATA_A710_2136059``: This applies errata 2136059 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_2282622``: This applies errata 2282622 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 440For Neoverse N2, the following errata build flags are defined : 441 442- ``ERRATA_N2_2002655``: This applies errata 2002655 workaround to Neoverse-N2 443 CPU. This needs to be enabled for revision r0p0 of the CPU, it is still open. 444 445- ``ERRATA_N2_2067956``: This applies errata 2067956 workaround to Neoverse-N2 446 CPU. This needs to be enabled for revision r0p0 of the CPU and is still open. 447 448- ``ERRATA_N2_2025414``: This applies errata 2025414 workaround to Neoverse-N2 449 CPU. This needs to be enabled for revision r0p0 of the CPU and is still open. 450 451- ``ERRATA_N2_2189731``: This applies errata 2189731 workaround to Neoverse-N2 452 CPU. This needs to be enabled for revision r0p0 of the CPU and is still open. 453 454- ``ERRATA_N2_2138956``: This applies errata 2138956 workaround to Neoverse-N2 455 CPU. This needs to be enabled for revision r0p0 of the CPU and is still open. 456 457- ``ERRATA_N2_2138953``: This applies errata 2138953 workaround to Neoverse-N2 458 CPU. This needs to be enabled for revision r0p0 of the CPU and is still open. 459 460- ``ERRATA_N2_2242415``: This applies errata 2242415 workaround to Neoverse-N2 461 CPU. This needs to be enabled for revision r0p0 of the CPU and is still open. 462 463- ``ERRATA_N2_2138958``: This applies errata 2138958 workaround to Neoverse-N2 464 CPU. This needs to be enabled for revision r0p0 of the CPU and is still open. 465 466- ``ERRATA_N2_2242400``: This applies errata 2242400 workaround to Neoverse-N2 467 CPU. This needs to be enabled for revision r0p0 of the CPU and is still open. 468 469- ``ERRATA_N2_2280757``: This applies errata 2280757 workaround to Neoverse-N2 470 CPU. This needs to be enabled for revision r0p0 of the CPU and is still open. 471 472For Cortex-X2, the following errata build flags are defined : 473 474- ``ERRATA_X2_2002765``: This applies errata 2002765 workaround to Cortex-X2 475 CPU. This needs to be enabled for revisions r0p0, r1p0, and r2p0 of the CPU, 476 it is still open. 477 478- ``ERRATA_X2_2058056``: This applies errata 2058056 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_2083908``: This applies errata 2083908 workaround to Cortex-X2 483 CPU. This needs to be enabled for revision r2p0 of the CPU, it is still open. 484 485- ``ERRATA_X2_2017096``: This applies errata 2017096 workaround to 486 Cortex-X2 CPU. This needs to be enabled only for revisions r0p0, r1p0 and 487 r2p0 of the CPU, it is fixed in r2p1. 488 489- ``ERRATA_X2_2081180``: This applies errata 2081180 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_2216384``: This applies errata 2216384 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_2147715``: This applies errata 2147715 workaround to 498 Cortex-X2 CPU. This needs to be enabled only for revision r2p0 of the CPU, 499 it is fixed in r2p1. 500 501For Cortex-A510, the following errata build flags are defined : 502 503- ``ERRATA_A510_1922240``: This applies errata 1922240 workaround to 504 Cortex-A510 CPU. This needs to be enabled only for revision r0p0, it is 505 fixed in r0p1. 506 507- ``ERRATA_A510_2288014``: This applies errata 2288014 workaround to 508 Cortex-A510 CPU. This needs to be enabled only for revisions r0p0, r0p1, 509 r0p2, r0p3 and r1p0, it is fixed in r1p1. 510 511- ``ERRATA_A510_2042739``: This applies errata 2042739 workaround to 512 Cortex-A510 CPU. This needs to be enabled only for revisions r0p0, r0p1 and 513 r0p2, it is fixed in r0p3. 514 515- ``ERRATA_A510_2041909``: This applies errata 2041909 workaround to 516 Cortex-A510 CPU. This needs to be enabled only for revision r0p2 and is fixed 517 in r0p3. The issue is also present in r0p0 and r0p1 but there is no 518 workaround for those revisions. 519 520- ``ERRATA_A510_2250311``: This applies errata 2250311 workaround to 521 Cortex-A510 CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2, 522 r0p3 and r1p0, it is fixed in r1p1. This workaround disables MPMM even if 523 ENABLE_MPMM=1. 524 525- ``ERRATA_A510_2218950``: This applies errata 2218950 workaround to 526 Cortex-A510 CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2, 527 r0p3 and r1p0, it is fixed in r1p1. 528 529- ``ERRATA_A510_2172148``: This applies errata 2172148 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 533DSU Errata Workarounds 534---------------------- 535 536Similar to CPU errata, TF-A also implements workarounds for DSU (DynamIQ 537Shared Unit) errata. The DSU errata details can be found in the respective Arm 538documentation: 539 540- `Arm DSU Software Developers Errata Notice`_. 541 542Each erratum is identified by an ``ID``, as defined in the DSU errata notice 543document. Thus, the build flags which enable/disable the errata workarounds 544have the format ``ERRATA_DSU_<ID>``. The implementation and application logic 545of DSU errata workarounds are similar to `CPU errata workarounds`_. 546 547For DSU errata, the following build flags are defined: 548 549- ``ERRATA_DSU_798953``: This applies errata 798953 workaround for the 550 affected DSU configurations. This errata applies only for those DSUs that 551 revision is r0p0 (on r0p1 it is fixed). However, please note that this 552 workaround results in increased DSU power consumption on idle. 553 554- ``ERRATA_DSU_936184``: This applies errata 936184 workaround for the 555 affected DSU configurations. This errata applies only for those DSUs that 556 contain the ACP interface **and** the DSU revision is older than r2p0 (on 557 r2p0 it is fixed). However, please note that this workaround results in 558 increased DSU power consumption on idle. 559 560CPU Specific optimizations 561-------------------------- 562 563This section describes some of the optimizations allowed by the CPU micro 564architecture that can be enabled by the platform as desired. 565 566- ``SKIP_A57_L1_FLUSH_PWR_DWN``: This flag enables an optimization in the 567 Cortex-A57 cluster power down sequence by not flushing the Level 1 data 568 cache. The L1 data cache and the L2 unified cache are inclusive. A flush 569 of the L2 by set/way flushes any dirty lines from the L1 as well. This 570 is a known safe deviation from the Cortex-A57 TRM defined power down 571 sequence. Each Cortex-A57 based platform must make its own decision on 572 whether to use the optimization. 573 574- ``A53_DISABLE_NON_TEMPORAL_HINT``: This flag disables the cache non-temporal 575 hint. The LDNP/STNP instructions as implemented on Cortex-A53 do not behave 576 in a way most programmers expect, and will most probably result in a 577 significant speed degradation to any code that employs them. The Armv8-A 578 architecture (see Arm DDI 0487A.h, section D3.4.3) allows cores to ignore 579 the non-temporal hint and treat LDNP/STNP as LDP/STP instead. Enabling this 580 flag enforces this behaviour. This needs to be enabled only for revisions 581 <= r0p3 of the CPU and is enabled by default. 582 583- ``A57_DISABLE_NON_TEMPORAL_HINT``: This flag has the same behaviour as 584 ``A53_DISABLE_NON_TEMPORAL_HINT`` but for Cortex-A57. This needs to be 585 enabled only for revisions <= r1p2 of the CPU and is enabled by default, 586 as recommended in section "4.7 Non-Temporal Loads/Stores" of the 587 `Cortex-A57 Software Optimization Guide`_. 588 589- ''A57_ENABLE_NON_CACHEABLE_LOAD_FWD'': This flag enables non-cacheable 590 streaming enhancement feature for Cortex-A57 CPUs. Platforms can set 591 this bit only if their memory system meets the requirement that cache 592 line fill requests from the Cortex-A57 processor are atomic. Each 593 Cortex-A57 based platform must make its own decision on whether to use 594 the optimization. This flag is disabled by default. 595 596- ``NEOVERSE_Nx_EXTERNAL_LLC``: This flag indicates that an external last 597 level cache(LLC) is present in the system, and that the DataSource field 598 on the master CHI interface indicates when data is returned from the LLC. 599 This is used to control how the LL_CACHE* PMU events count. 600 Default value is 0 (Disabled). 601 602-------------- 603 604*Copyright (c) 2014-2021, Arm Limited and Contributors. All rights reserved.* 605 606.. _CVE-2017-5715: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-5715 607.. _CVE-2018-3639: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-3639 608.. _CVE-2022-23960: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-23960 609.. _Cortex-A53 MPCore Software Developers Errata Notice: http://infocenter.arm.com/help/topic/com.arm.doc.epm048406/index.html 610.. _Cortex-A57 MPCore Software Developers Errata Notice: http://infocenter.arm.com/help/topic/com.arm.doc.epm049219/index.html 611.. _Cortex-A72 MPCore Software Developers Errata Notice: http://infocenter.arm.com/help/topic/com.arm.doc.epm012079/index.html 612.. _Cortex-A57 Software Optimization Guide: http://infocenter.arm.com/help/topic/com.arm.doc.uan0015b/Cortex_A57_Software_Optimization_Guide_external.pdf 613.. _Arm DSU Software Developers Errata Notice: http://infocenter.arm.com/help/topic/com.arm.doc.epm138168/index.html 614