xref: /rk3399_ARM-atf/docs/design/cpu-specific-build-macros.rst (revision fd2fb5b7612810ee53ab6bce74dffe955e1f252a)
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-  ``WORKAROUND_CVE_2024_5660``: Enables mitigation for `CVE-2024-5660`.
37   The fix is to disable hardware page aggregation by setting CPUECTLR_EL1[46]
38   in EL3 FW. This build option should be set to 1 if the target platform contains
39   at least 1 CPU that requires this mitigation. Defaults to 1.
40
41-  ``WORKAROUND_CVE_2024_7881``: Enables mitigation for `CVE-2024-7881`.
42   This build option should be set to 1 if the target platform contains at
43   least 1 CPU that requires this mitigation. Defaults to 1.
44
45.. _arm_cpu_macros_errata_workarounds:
46
47CPU Errata Workarounds
48----------------------
49
50TF-A exports a series of build flags which control the errata workarounds that
51are applied to each CPU by the reset handler. The errata details can be found
52in the CPU specific errata documents published by Arm:
53For example: `Cortex-A72 MPCore Software Developers Errata Notice`_
54
55The errata workarounds are implemented for a particular revision or a set of
56processor revisions. This is checked by the reset handler at runtime. Each
57errata workaround is identified by its ``ID`` as specified in the processor's
58errata notice document. The format of the define used to enable/disable the
59errata workaround is ``ERRATA_<Processor name>_<ID>``, where the ``Processor name``
60is for example ``A57`` for the ``Cortex_A57`` CPU.
61
62Refer to :ref:`firmware_design_cpu_errata_implementation` for information on how to
63write errata workaround functions.
64
65All workarounds are disabled by default. The platform is responsible for
66enabling these workarounds according to its requirement by defining the
67errata workaround build flags in the platform specific makefile. In case
68these workarounds are enabled for the wrong CPU revision then the errata
69workaround is not applied. In the DEBUG build, this is indicated by
70printing a warning to the crash console.
71
72In the current implementation, a platform which has more than 1 variant
73with different revisions of a processor has no runtime mechanism available
74for it to specify which errata workarounds should be enabled or not.
75
76The value of the build flags is 0 by default, that is, disabled. A value of 1
77will enable it.
78
79For Cortex-A9, the following errata build flags are defined :
80
81-  ``ERRATA_A9_794073``: This applies errata 794073 workaround to Cortex-A9
82   CPU. This needs to be enabled for all revisions of the CPU.
83
84For Cortex-A15, the following errata build flags are defined :
85
86-  ``ERRATA_A15_816470``: This applies errata 816470 workaround to Cortex-A15
87   CPU. This needs to be enabled only for revision >= r3p0 of the CPU.
88
89-  ``ERRATA_A15_827671``: This applies errata 827671 workaround to Cortex-A15
90   CPU. This needs to be enabled only for revision >= r3p0 of the CPU.
91
92For Cortex-A17, the following errata build flags are defined :
93
94-  ``ERRATA_A17_852421``: This applies errata 852421 workaround to Cortex-A17
95   CPU. This needs to be enabled only for revision <= r1p2 of the CPU.
96
97-  ``ERRATA_A17_852423``: This applies errata 852423 workaround to Cortex-A17
98   CPU. This needs to be enabled only for revision <= r1p2 of the CPU.
99
100For Cortex-A35, the following errata build flags are defined :
101
102-  ``ERRATA_A35_855472``: This applies errata 855472 workaround to Cortex-A35
103   CPUs. This needs to be enabled only for revision r0p0 of Cortex-A35.
104
105For Cortex-A53, the following errata build flags are defined :
106
107-  ``ERRATA_A53_819472``: This applies errata 819472 workaround to all
108   CPUs. This needs to be enabled only for revision <= r0p1 of Cortex-A53.
109
110-  ``ERRATA_A53_824069``: This applies errata 824069 workaround to all
111   CPUs. This needs to be enabled only for revision <= r0p2 of Cortex-A53.
112
113-  ``ERRATA_A53_826319``: This applies errata 826319 workaround to Cortex-A53
114   CPU. This needs to be enabled only for revision <= r0p2 of the CPU.
115
116-  ``ERRATA_A53_827319``: This applies errata 827319 workaround to all
117   CPUs. This needs to be enabled only for revision <= r0p2 of Cortex-A53.
118
119-  ``ERRATA_A53_835769``: This applies erratum 835769 workaround at compile and
120   link time to Cortex-A53 CPU. This needs to be enabled for some variants of
121   revision <= r0p4. This workaround can lead the linker to create ``*.stub``
122   sections.
123
124-  ``ERRATA_A53_836870``: This applies errata 836870 workaround to Cortex-A53
125   CPU. This needs to be enabled only for revision <= r0p3 of the CPU. From
126   r0p4 and onwards, this errata is enabled by default in hardware. Identical to
127   ``A53_DISABLE_NON_TEMPORAL_HINT``.
128
129-  ``ERRATA_A53_843419``: This applies erratum 843419 workaround at link time
130   to Cortex-A53 CPU.  This needs to be enabled for some variants of revision
131   <= r0p4. This workaround can lead the linker to emit ``*.stub`` sections
132   which are 4kB aligned.
133
134-  ``ERRATA_A53_855873``: This applies errata 855873 workaround to Cortex-A53
135   CPUs. Though the erratum is present in every revision of the CPU,
136   this workaround is only applied to CPUs from r0p3 onwards, which feature
137   a chicken bit in CPUACTLR_EL1 to enable a hardware workaround.
138   Earlier revisions of the CPU have other errata which require the same
139   workaround in software, so they should be covered anyway.
140
141-  ``ERRATA_A53_1530924``: This applies errata 1530924 workaround to all
142   revisions of Cortex-A53 CPU.
143
144For Cortex-A55, the following errata build flags are defined :
145
146-  ``ERRATA_A55_768277``: This applies errata 768277 workaround to Cortex-A55
147   CPU. This needs to be enabled only for revision r0p0 of the CPU.
148
149-  ``ERRATA_A55_778703``: This applies errata 778703 workaround to Cortex-A55
150   CPU. This needs to be enabled only for revision r0p0 of the CPU.
151
152-  ``ERRATA_A55_798797``: This applies errata 798797 workaround to Cortex-A55
153   CPU. This needs to be enabled only for revision r0p0 of the CPU.
154
155-  ``ERRATA_A55_846532``: This applies errata 846532 workaround to Cortex-A55
156   CPU. This needs to be enabled only for revision <= r0p1 of the CPU.
157
158-  ``ERRATA_A55_903758``: This applies errata 903758 workaround to Cortex-A55
159   CPU. This needs to be enabled only for revision <= r0p1 of the CPU.
160
161-  ``ERRATA_A55_1221012``: This applies errata 1221012 workaround to Cortex-A55
162   CPU. This needs to be enabled only for revision <= r1p0 of the CPU.
163
164-  ``ERRATA_A55_1530923``: This applies errata 1530923 workaround to all
165   revisions of Cortex-A55 CPU.
166
167For Cortex-A57, the following errata build flags are defined :
168
169-  ``ERRATA_A57_806969``: This applies errata 806969 workaround to Cortex-A57
170   CPU. This needs to be enabled only for revision r0p0 of the CPU.
171
172-  ``ERRATA_A57_813419``: This applies errata 813419 workaround to Cortex-A57
173   CPU. This needs to be enabled only for revision r0p0 of the CPU.
174
175-  ``ERRATA_A57_813420``: This applies errata 813420 workaround to Cortex-A57
176   CPU. This needs to be enabled only for revision r0p0 of the CPU.
177
178-  ``ERRATA_A57_814670``: This applies errata 814670 workaround to Cortex-A57
179   CPU. This needs to be enabled only for revision r0p0 of the CPU.
180
181-  ``ERRATA_A57_817169``: This applies errata 817169 workaround to Cortex-A57
182   CPU. This needs to be enabled only for revision <= r0p1 of the CPU.
183
184-  ``ERRATA_A57_826974``: This applies errata 826974 workaround to Cortex-A57
185   CPU. This needs to be enabled only for revision <= r1p1 of the CPU.
186
187-  ``ERRATA_A57_826977``: This applies errata 826977 workaround to Cortex-A57
188   CPU. This needs to be enabled only for revision <= r1p1 of the CPU.
189
190-  ``ERRATA_A57_828024``: This applies errata 828024 workaround to Cortex-A57
191   CPU. This needs to be enabled only for revision <= r1p1 of the CPU.
192
193-  ``ERRATA_A57_829520``: This applies errata 829520 workaround to Cortex-A57
194   CPU. This needs to be enabled only for revision <= r1p2 of the CPU.
195
196-  ``ERRATA_A57_833471``: This applies errata 833471 workaround to Cortex-A57
197   CPU. This needs to be enabled only for revision <= r1p2 of the CPU.
198
199-  ``ERRATA_A57_859972``: This applies errata 859972 workaround to Cortex-A57
200   CPU. This needs to be enabled only for revision <= r1p3 of the CPU.
201
202-  ``ERRATA_A57_1319537``: This applies errata 1319537 workaround to all
203   revisions of Cortex-A57 CPU.
204
205For Cortex-A65, the following errata build flags are defined :
206
207-  ``ERRATA_A65_1179935``: This applies errata 1179935 workaround to Cortex-A65
208   CPU. This needs to be enabled only for revision r0p0 of the CPU, and is fixed
209   in r1p0.
210
211-  ``ERRATA_A65_1227419``: This applies errata 1227419 workaround to Cortex-A65
212   CPU. This needs to be enabled only for revision r0p0 and r1p0 of the CPU and
213   is fixed in r1p1.
214
215-  ``ERRATA_A65_1541130``: This applies errata 1541130 workaround to r0p0, r1p0,
216   r1p1, r1p2 revisions of the CPU and is still open.
217
218For Cortex-A72, the following errata build flags are defined :
219
220-  ``ERRATA_A72_859971``: This applies errata 859971 workaround to Cortex-A72
221   CPU. This needs to be enabled only for revision <= r0p3 of the CPU.
222
223-  ``ERRATA_A72_1319367``: This applies errata 1319367 workaround to all
224   revisions of Cortex-A72 CPU.
225
226For Cortex-A73, the following errata build flags are defined :
227
228-  ``ERRATA_A73_852427``: This applies errata 852427 workaround to Cortex-A73
229   CPU. This needs to be enabled only for revision r0p0 of the CPU.
230
231-  ``ERRATA_A73_855423``: This applies errata 855423 workaround to Cortex-A73
232   CPU. This needs to be enabled only for revision <= r0p1 of the CPU.
233
234For Cortex-A75, the following errata build flags are defined :
235
236-  ``ERRATA_A75_764081``: This applies errata 764081 workaround to Cortex-A75
237   CPU. This needs to be enabled only for revision r0p0 of the CPU.
238
239-  ``ERRATA_A75_790748``: This applies errata 790748 workaround to Cortex-A75
240    CPU. This needs to be enabled only for revision r0p0 of the CPU.
241
242For Cortex-A76, the following errata build flags are defined :
243
244-  ``ERRATA_A76_1073348``: This applies errata 1073348 workaround to Cortex-A76
245   CPU. This needs to be enabled only for revision <= r1p0 of the CPU.
246
247-  ``ERRATA_A76_1130799``: This applies errata 1130799 workaround to Cortex-A76
248   CPU. This needs to be enabled only for revision <= r2p0 of the CPU.
249
250-  ``ERRATA_A76_1220197``: This applies errata 1220197 workaround to Cortex-A76
251   CPU. This needs to be enabled only for revision <= r2p0 of the CPU.
252
253-  ``ERRATA_A76_1257314``: This applies errata 1257314 workaround to Cortex-A76
254   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
255
256-  ``ERRATA_A76_1262606``: This applies errata 1262606 workaround to Cortex-A76
257   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
258
259-  ``ERRATA_A76_1262888``: This applies errata 1262888 workaround to Cortex-A76
260   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
261
262-  ``ERRATA_A76_1275112``: This applies errata 1275112 workaround to Cortex-A76
263   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
264
265-  ``ERRATA_A76_1791580``: This applies errata 1791580 workaround to Cortex-A76
266   CPU. This needs to be enabled only for revision <= r4p0 of the CPU.
267
268-  ``ERRATA_A76_1165522``: This applies errata 1165522 workaround to all
269   revisions of Cortex-A76 CPU. This errata is fixed in r3p0 but due to
270   limitation of errata framework this errata is applied to all revisions
271   of Cortex-A76 CPU.
272
273-  ``ERRATA_A76_1868343``: This applies errata 1868343 workaround to Cortex-A76
274   CPU. This needs to be enabled only for revision <= r4p0 of the CPU.
275
276-  ``ERRATA_A76_1946160``: This applies errata 1946160 workaround to Cortex-A76
277   CPU. This needs to be enabled only for revisions r3p0 - r4p1 of the CPU.
278
279-  ``ERRATA_A76_2743102``: This applies errata 2743102 workaround to Cortex-A76
280   CPU. This needs to be enabled for all revisions <= r4p1 of the CPU and is
281   still open.
282
283For Cortex-A76AE, the following errata build flags are defined :
284
285-  ``ERRATA_A76AE_1931427``: This applies errata 1931427 workaround to Cortex-A76AE
286   CPU. This needs to be enabled for revision r0p0 and r1p0 of the CPU and it is
287   fixed in r1p1.
288
289-  ``ERRATA_A76AE_1931435``: This applies errata 1931435 workaround to Cortex-A76AE
290   CPU. This needs to be enabled for revision r0p0 and r1p0 of the CPU and it is
291   fixed in r1p1.
292
293-  ``ERRATA_A76AE_1969401``: This applies errata 1969401 workaround to Cortex-A76AE
294   CPU. This needs to be enabled for revision r0p0 and r1p0 of the CPU and it is
295   fixed in r1p1.
296
297-  ``ERRATA_A76AE_2371140``: This applies errata 2371140 workaround to Cortex-A76AE
298   CPU. This needs to be enabled for all revisions <= r1p1 of the CPU and is
299   still open.
300
301For Cortex-A77, the following errata build flags are defined :
302
303-  ``ERRATA_A77_1508412``: This applies errata 1508412 workaround to Cortex-A77
304   CPU. This needs to be enabled only for revision <= r1p0 of the CPU.
305
306-  ``ERRATA_A77_1925769``: This applies errata 1925769 workaround to Cortex-A77
307   CPU. This needs to be enabled only for revision <= r1p1 of the CPU.
308
309-  ``ERRATA_A77_1946167``: This applies errata 1946167 workaround to Cortex-A77
310   CPU. This needs to be enabled only for revision <= r1p1 of the CPU.
311
312-  ``ERRATA_A77_1791578``: This applies errata 1791578 workaround to Cortex-A77
313   CPU. This needs to be enabled for r0p0, r1p0, and r1p1, it is still open.
314
315-  ``ERRATA_A77_2356587``: This applies errata 2356587 workaround to Cortex-A77
316   CPU. This needs to be enabled for r0p0, r1p0, and r1p1, it is still open.
317
318 -  ``ERRATA_A77_1800714``: This applies errata 1800714 workaround to Cortex-A77
319    CPU. This needs to be enabled for revisions <= r1p1 of the CPU.
320
321 -  ``ERRATA_A77_2743100``: This applies errata 2743100 workaround to Cortex-A77
322    CPU. This needs to be enabled for r0p0, r1p0, and r1p1, it is still open.
323
324For Cortex-A78, the following errata build flags are defined :
325
326-  ``ERRATA_A78_1688305``: This applies errata 1688305 workaround to Cortex-A78
327   CPU. This needs to be enabled only for revision r0p0 - r1p0 of the CPU.
328
329-  ``ERRATA_A78_1941498``: This applies errata 1941498 workaround to Cortex-A78
330   CPU. This needs to be enabled for revisions r0p0, r1p0, and r1p1 of the CPU.
331
332-  ``ERRATA_A78_1951500``: This applies errata 1951500 workaround to Cortex-A78
333   CPU. This needs to be enabled for revisions r1p0 and r1p1, r0p0 has the same
334   issue but there is no workaround for that revision.
335
336-  ``ERRATA_A78_1821534``: This applies errata 1821534 workaround to Cortex-A78
337   CPU. This needs to be enabled for revisions r0p0 and r1p0.
338
339-  ``ERRATA_A78_1952683``: This applies errata 1952683 workaround to Cortex-A78
340   CPU. This needs to be enabled for revision r0p0, it is fixed in r1p0.
341
342-  ``ERRATA_A78_2242635``: This applies errata 2242635 workaround to Cortex-A78
343   CPU. This needs to be enabled for revisions r1p0, r1p1, and r1p2. The issue
344   is present in r0p0 but there is no workaround. It is still open.
345
346-  ``ERRATA_A78_2376745``: This applies errata 2376745 workaround to Cortex-A78
347   CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1, and r1p2, and
348   it is still open.
349
350-  ``ERRATA_A78_2395406``: This applies errata 2395406 workaround to Cortex-A78
351   CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1, and r1p2, and
352   it is still open.
353
354- ``ERRATA_A78_2712571``: This applies erratum 2712571 workaround to Cortex-A78
355   CPU, this erratum affects system configurations that do not use an ARM
356   interconnect IP. This needs to be enabled for revisions r0p0, r1p0, r1p1
357   and r1p2 and it is still open.
358
359-  ``ERRATA_A78_2742426``: This applies erratum 2742426 workaround to Cortex-A78
360   CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1 and r1p2 and
361   it is still open.
362
363-  ``ERRATA_A78_2772019``: This applies errata 2772019 workaround to Cortex-A78
364   CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1, and r1p2, and
365   it is still open.
366
367-  ``ERRATA_A78_2779479``: This applies erratum 2779479 workaround to Cortex-A78
368   CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1 and r1p2 and
369   it is still open.
370
371For Cortex-A78AE, the following errata build flags are defined :
372
373- ``ERRATA_A78_AE_1941500`` : This applies errata 1941500 workaround to
374   Cortex-A78AE CPU. This needs to be enabled for revisions r0p0 and r0p1.
375   This erratum is still open.
376
377- ``ERRATA_A78_AE_1951502`` : This applies errata 1951502 workaround to
378  Cortex-A78AE CPU. This needs to be enabled for revisions r0p0 and r0p1. This
379  erratum is still open.
380
381- ``ERRATA_A78_AE_2376748`` : This applies errata 2376748 workaround to
382  Cortex-A78AE CPU. This needs to be enabled for revisions r0p0, r0p1 and r0p2.
383  This erratum is still open.
384
385- ``ERRATA_A78_AE_2395408`` : This applies errata 2395408 workaround to
386  Cortex-A78AE CPU. This needs to be enabled for revisions r0p0 and r0p1. This
387  erratum is still open.
388
389- ``ERRATA_A78_AE_2712574`` : This applies erratum 2712574 workaround to
390  Cortex-A78AE CPU. This erratum affects system configurations that do not use
391  an ARM interconnect IP. This needs to be enabled for revisions r0p0, r0p1 and
392  r0p2. This erratum is still open.
393
394For Cortex-A78C, the following errata build flags are defined :
395
396- ``ERRATA_A78C_1827430`` : This applies errata 1827430 workaround to
397  Cortex-A78C CPU. This needs to be enabled for revision r0p0. The erratum is
398  fixed in r0p1.
399
400- ``ERRATA_A78C_1827440`` : This applies errata 1827440 workaround to
401  Cortex-A78C CPU. This needs to be enabled for revision r0p0. The erratum is
402  fixed in r0p1.
403
404- ``ERRATA_A78C_2242638`` : This applies errata 2242638 workaround to
405  Cortex-A78C CPU. This needs to be enabled for revisions r0p1, r0p2 and
406  it is still open.
407
408- ``ERRATA_A78C_2376749`` : This applies errata 2376749 workaround to
409  Cortex-A78C CPU. This needs to be enabled for revisions r0p1 and r0p2. This
410  erratum is still open.
411
412- ``ERRATA_A78C_2395411`` : This applies errata 2395411 workaround to
413  Cortex-A78C CPU. This needs to be enabled for revisions r0p1 and r0p2. This
414  erratum is still open.
415
416- ``ERRATA_A78C_2683027`` : This applies errata 2683027 workaround to
417  Cortex-A78C CPU. This needs to be enabled for revisions r0p1 and r0p2. This
418  erratum is still open.
419
420- ``ERRATA_A78C_2712575`` : This applies erratum 2712575 workaround to
421  Cortex-A78C CPU, this erratum affects system configurations that do not use
422  an ARM interconnect IP. This needs to be enabled for revisions r0p1 and r0p2
423  and is still open.
424
425- ``ERRATA_A78C_2743232`` : This applies erratum 2743232 workaround to
426  Cortex-A78C CPU. This needs to be enabled for revisions r0p1 and r0p2.
427  This erratum is still open.
428
429- ``ERRATA_A78C_2772121`` : This applies errata 2772121 workaround to
430  Cortex-A78C CPU. This needs to be enabled for revisions r0p0, r0p1 and r0p2.
431  This erratum is still open.
432
433- ``ERRATA_A78C_2779484`` : This applies errata 2779484 workaround to
434  Cortex-A78C CPU. This needs to be enabled for revisions r0p1 and r0p2.
435  This erratum is still open.
436
437For Cortex-X1 CPU, the following errata build flags are defined:
438
439- ``ERRATA_X1_1821534`` : This applies errata 1821534 workaround to Cortex-X1
440   CPU. This needs to be enabled only for revision <= r1p0 of the CPU.
441
442- ``ERRATA_X1_1688305`` : This applies errata 1688305 workaround to Cortex-X1
443   CPU. This needs to be enabled only for revision <= r1p0 of the CPU.
444
445- ``ERRATA_X1_1827429`` : This applies errata 1827429 workaround to Cortex-X1
446   CPU. This needs to be enabled only for revision <= r1p0 of the CPU.
447
448For Neoverse N1, the following errata build flags are defined :
449
450-  ``ERRATA_N1_1073348``: This applies errata 1073348 workaround to Neoverse-N1
451   CPU. This needs to be enabled only for revision r0p0 and r1p0 of the CPU.
452
453-  ``ERRATA_N1_1130799``: This applies errata 1130799 workaround to Neoverse-N1
454   CPU. This needs to be enabled only for revision <= r2p0 of the CPU.
455
456-  ``ERRATA_N1_1165347``: This applies errata 1165347 workaround to Neoverse-N1
457   CPU. This needs to be enabled only for revision <= r2p0 of the CPU.
458
459-  ``ERRATA_N1_1207823``: This applies errata 1207823 workaround to Neoverse-N1
460   CPU. This needs to be enabled only for revision <= r2p0 of the CPU.
461
462-  ``ERRATA_N1_1220197``: This applies errata 1220197 workaround to Neoverse-N1
463   CPU. This needs to be enabled only for revision <= r2p0 of the CPU.
464
465-  ``ERRATA_N1_1257314``: This applies errata 1257314 workaround to Neoverse-N1
466   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
467
468-  ``ERRATA_N1_1262606``: This applies errata 1262606 workaround to Neoverse-N1
469   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
470
471-  ``ERRATA_N1_1262888``: This applies errata 1262888 workaround to Neoverse-N1
472   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
473
474-  ``ERRATA_N1_1275112``: This applies errata 1275112 workaround to Neoverse-N1
475   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
476
477-  ``ERRATA_N1_1315703``: This applies errata 1315703 workaround to Neoverse-N1
478   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
479
480-  ``ERRATA_N1_1542419``: This applies errata 1542419 workaround to Neoverse-N1
481   CPU. This needs to be enabled only for revisions r3p0 - r4p0 of the CPU.
482
483-  ``ERRATA_N1_1868343``: This applies errata 1868343 workaround to Neoverse-N1
484   CPU. This needs to be enabled only for revision <= r4p0 of the CPU.
485
486-  ``ERRATA_N1_1946160``: This applies errata 1946160 workaround to Neoverse-N1
487   CPU. This needs to be enabled for revisions r3p0, r3p1, r4p0, and r4p1, for
488   revisions r0p0, r1p0, and r2p0 there is no workaround.
489
490-  ``ERRATA_N1_2743102``: This applies errata 2743102 workaround to Neoverse-N1
491   CPU. This needs to be enabled for all revisions <= r4p1 of the CPU and is
492   still open.
493
494For Neoverse V1, the following errata build flags are defined :
495
496-  ``ERRATA_V1_1618635``: This applies errata 1618635 workaround to Neoverse-V1
497   CPU. This needs to be enabled for revision r0p0 of the CPU, it is fixed in
498   r1p0.
499
500-  ``ERRATA_V1_1774420``: This applies errata 1774420 workaround to Neoverse-V1
501   CPU. This needs to be enabled only for revisions r0p0 and r1p0, it is fixed
502   in r1p1.
503
504-  ``ERRATA_V1_1791573``: This applies errata 1791573 workaround to Neoverse-V1
505   CPU. This needs to be enabled only for revisions r0p0 and r1p0, it is fixed
506   in r1p1.
507
508-  ``ERRATA_V1_1852267``: This applies errata 1852267 workaround to Neoverse-V1
509   CPU. This needs to be enabled only for revisions r0p0 and r1p0, it is fixed
510   in r1p1.
511
512-  ``ERRATA_V1_1925756``: This applies errata 1925756 workaround to Neoverse-V1
513   CPU. This needs to be enabled for r0p0, r1p0, and r1p1, it is still open.
514
515-  ``ERRATA_V1_1940577``: This applies errata 1940577 workaround to Neoverse-V1
516   CPU. This needs to be enabled only for revision r1p0 and r1p1 of the
517   CPU.
518
519-  ``ERRATA_V1_1966096``: This applies errata 1966096 workaround to Neoverse-V1
520   CPU. This needs to be enabled for revisions r1p0 and r1p1 of the CPU, the
521   issue is present in r0p0 as well but there is no workaround for that
522   revision.  It is still open.
523
524-  ``ERRATA_V1_2139242``: This applies errata 2139242 workaround to Neoverse-V1
525   CPU. This needs to be enabled for revisions r0p0, r1p0, and r1p1 of the
526   CPU.  It is still open.
527
528-  ``ERRATA_V1_2216392``: This applies errata 2216392 workaround to Neoverse-V1
529   CPU. This needs to be enabled for revisions r1p0 and r1p1 of the CPU, the
530   issue is present in r0p0 as well but there is no workaround for that
531   revision.  It is still open.
532
533-  ``ERRATA_V1_2294912``: This applies errata 2294912 workaround to Neoverse-V1
534   CPU. This needs to be enabled for revisions r0p0, r1p0, and r1p1 and r1p2 of
535   the CPU.
536
537-  ``ERRATA_V1_2348377``: This applies errata 2348377 workaroud to Neoverse-V1
538   CPU. This needs to be enabled for revisions r0p0, r1p0 and r1p1 of the CPU.
539   It has been fixed in r1p2.
540
541-  ``ERRATA_V1_2372203``: This applies errata 2372203 workaround to Neoverse-V1
542   CPU. This needs to be enabled for revisions r0p0, r1p0 and r1p1 of the CPU.
543   It is still open.
544
545- ``ERRATA_V1_2701953``: This applies erratum 2701953 workaround to Neoverse-V1
546   CPU, this erratum affects system configurations that do not use an ARM
547   interconnect IP. This needs to be enabled for revisions r0p0, r1p0 and r1p1.
548   It has been fixed in r1p2.
549
550-  ``ERRATA_V1_2743093``: This applies errata 2743093 workaround to Neoverse-V1
551   CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1 and r1p2 of the
552   CPU. It is still open.
553
554-  ``ERRATA_V1_2743233``: This applies erratum 2743233 workaround to Neoverse-V1
555   CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1, and r1p2 of the
556   CPU. It is still open.
557
558-  ``ERRATA_V1_2779461``: This applies erratum 2779461 workaround to Neoverse-V1
559   CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1, r1p2 of the
560   CPU. It is still open.
561
562For Neoverse V2, the following errata build flags are defined :
563
564-  ``ERRATA_V2_2618597``: This applies errata 2618597 workaround to Neoverse-V2
565   CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in
566   r0p2.
567
568-  ``ERRATA_V2_2662553``: This applies errata 2662553 workaround to Neoverse-V2
569   CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in
570   r0p2.
571
572-  ``ERRATA_V2_2719103``: This applies errata 2719103 workaround to Neoverse-V2
573   CPU, this affects system configurations that do not use and ARM interconnect
574   IP. This needs to be enabled for revisions r0p0 and r0p1. It has been fixed
575   in r0p2.
576
577-  ``ERRATA_V2_2719105``: This applies errata 2719105 workaround to Neoverse-V2
578   CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in
579   r0p2.
580
581-  ``ERRATA_V2_2743011``: This applies errata 2743011 workaround to Neoverse-V2
582   CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in
583   r0p2.
584
585-  ``ERRATA_V2_2779510``: This applies errata 2779510 workaround to Neoverse-V2
586   CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in
587   r0p2.
588
589-  ``ERRATA_V2_2801372``: This applies errata 2801372 workaround to Neoverse-V2
590   CPU, this affects all configurations. This needs to be enabled for revisions
591   r0p0 and r0p1. It has been fixed in r0p2.
592
593-  ``ERRATA_V2_3701771``: This applies errata 3701771 workaround to Neoverse-V2
594   CPU. This needs to be enabled for revisions r0p0, r0p1 and r0p2 and is
595   still open.
596
597-  ``ERRATA_V2_3841324``: This applies errata 3841324 workaround to Neoverse-V2
598   CPU. This needs to be enabled only for revisions r0p0 and r0p1 of
599   the CPU. It is fixed in r0p2.
600
601For Neoverse V3, the following errata build flags are defined :
602
603- ``ERRATA_V3_2970647``: This applies errata 2970647 workaround to Neoverse-V3
604  CPU. This needs to be enabled for revision r0p0. It is fixed in r0p1.
605
606- ``ERRATA_V3_3701767``: This applies errata 3701767 workaround to Neoverse-V3
607  CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2 of the CPU and
608  is still open.
609
610For Cortex-A710, the following errata build flags are defined :
611
612-  ``ERRATA_A710_1901946``: This applies errata 1901946 workaround to
613   Cortex-A710 CPU. This needs to be enabled only for revision r1p0. It has
614   been fixed in r2p0.
615
616-  ``ERRATA_A710_1916945``: This applies errata 1916945 workaround to
617   Cortex-A710 CPU. This needs to be enabled only for revisions r0p0 and r1p0.
618   It has been fixed in r2p0.
619
620-  ``ERRATA_A710_1917258``: This applies errata 1917258 workaround to
621   Cortex-A710 CPU. This needs to be enabled only for revisions r0p0 and r1p0.
622   It has been fixed in r2p0.
623
624-  ``ERRATA_A710_1927200``: This applies errata 1927200 workaround to
625   Cortex-A710 CPU. This needs to be enabled only for revisions r0p0 and r1p0.
626   It has been fixed in r2p0.
627
628-  ``ERRATA_A710_1987031``: This applies errata 1987031 workaround to
629   Cortex-A710 CPU. This needs to be enabled only for revisions r0p0, r1p0 and
630   r2p0 of the CPU. It is still open.
631
632-  ``ERRATA_A710_2081180``: This applies errata 2081180 workaround to
633   Cortex-A710 CPU. This needs to be enabled only for revisions r0p0, r1p0 and
634   r2p0 of the CPU. It is still open.
635
636-  ``ERRATA_A710_2055002``: This applies errata 2055002 workaround to
637   Cortex-A710 CPU. This needs to be enabled for revisions r1p0, r2p0 of the CPU
638   and is still open.
639
640-  ``ERRATA_A710_2017096``: This applies errata 2017096 workaround to
641   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
642   of the CPU and is still open.
643
644-  ``ERRATA_A710_2083908``: This applies errata 2083908 workaround to
645   Cortex-A710 CPU. This needs to be enabled for revision r2p0 of the CPU and
646   is still open.
647
648-  ``ERRATA_A710_2267065``: This applies errata 2267065 workaround to
649   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
650   of the CPU and is fixed in r2p1.
651
652-  ``ERRATA_A710_2136059``: This applies errata 2136059 workaround to
653   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
654   of the CPU and is fixed in r2p1.
655
656-  ``ERRATA_A710_2147715``: This applies errata 2147715 workaround to
657   Cortex-A710 CPU. This needs to be enabled for revision r2p0 of the CPU
658   and is fixed in r2p1.
659
660-  ``ERRATA_A710_2216384``: This applies errata 2216384 workaround to
661   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
662   of the CPU and is fixed in r2p1.
663
664-  ``ERRATA_A710_2282622``: This applies errata 2282622 workaround to
665   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and
666   r2p1 of the CPU and is still open.
667
668- ``ERRATA_A710_2291219``: This applies errata 2291219 workaround to
669   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
670   of the CPU and is fixed in r2p1.
671
672-  ``ERRATA_A710_2008768``: This applies errata 2008768 workaround to
673   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
674   of the CPU and is fixed in r2p1.
675
676-  ``ERRATA_A710_2371105``: This applies errata 2371105 workaround to
677   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
678   of the CPU and is fixed in r2p1.
679
680-  ``ERRATA_A710_2701952``: This applies erratum 2701952 workaround to Cortex-A710
681   CPU, and applies to system configurations that do not use and ARM
682   interconnect IP. This needs to be enabled for r0p0, r1p0, r2p0 and r2p1 and
683   is still open.
684
685-  ``ERRATA_A710_2742423``: This applies errata 2742423 workaround to
686   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and
687   r2p1 of the CPU and is still open.
688
689-  ``ERRATA_A710_2768515``: This applies errata 2768515 workaround to
690   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and
691   r2p1 of the CPU and is still open.
692
693-  ``ERRATA_A710_2778471``: This applies errata 2778471 workaround to Cortex-A710
694   CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and r2p1 of the
695   CPU and is still open.
696
697- ``ERRATA_A710_3701772``: This applies errata 3701772 workaround to Cortex-A710
698  CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0, r2p1 of the
699  CPU and is still open.
700
701For Neoverse N2, the following errata build flags are defined :
702
703-  ``ERRATA_N2_2002655``: This applies errata 2002655 workaround to Neoverse-N2
704   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
705
706-  ``ERRATA_N2_2009478``: This applies errata 2009478 workaround to Neoverse-N2
707   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
708
709-  ``ERRATA_N2_2067956``: This applies errata 2067956 workaround to Neoverse-N2
710   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
711
712-  ``ERRATA_N2_2025414``: This applies errata 2025414 workaround to Neoverse-N2
713   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
714
715-  ``ERRATA_N2_2189731``: This applies errata 2189731 workaround to Neoverse-N2
716   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
717
718-  ``ERRATA_N2_2138956``: This applies errata 2138956 workaround to Neoverse-N2
719   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
720
721-  ``ERRATA_N2_2242415``: This applies errata 2242415 workaround to Neoverse-N2
722   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
723
724-  ``ERRATA_N2_2138958``: This applies errata 2138958 workaround to Neoverse-N2
725   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
726
727-  ``ERRATA_N2_2242400``: This applies errata 2242400 workaround to Neoverse-N2
728   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
729
730-  ``ERRATA_N2_2280757``: This applies errata 2280757 workaround to Neoverse-N2
731   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
732
733-  ``ERRATA_N2_2326639``: This applies errata 2326639 workaround to Neoverse-N2
734   CPU. This needs to be enabled for revision r0p0 of the CPU, it is fixed in
735   r0p1.
736
737-  ``ERRATA_N2_2340933``: This applies errata 2340933 workaround to Neoverse-N2
738   CPU. This needs to be enabled for revision r0p0 of the CPU, it is fixed in
739   r0p1.
740
741-  ``ERRATA_N2_2346952``: This applies errata 2346952 workaround to Neoverse-N2
742   CPU. This needs to be enabled for revisions r0p0, r0p1 and r0p2 of the CPU,
743   it is fixed in r0p3.
744
745-  ``ERRATA_N2_2376738``: This applies errata 2376738 workaround to Neoverse-N2
746   CPU. This needs to be enabled for revision r0p0, r0p1, r0p2, r0p3 and is still open.
747
748-  ``ERRATA_N2_2388450``: This applies errata 2388450 workaround to Neoverse-N2
749   CPU. This needs to be enabled for revision r0p0 of the CPU, it is fixed in
750   r0p1.
751
752-  ``ERRATA_N2_2743014``: This applies errata 2743014 workaround to Neoverse-N2
753   CPU. This needs to be enabled for revisions r0p0, r0p1 and r0p2. It is fixed
754   in r0p3.
755
756-  ``ERRATA_N2_2743089``: This applies errata 2743089 workaround to Neoverse-N2
757   CPU. This needs to be enabled for revisions r0p0, r0p1 and r0p2. It is fixed
758   in r0p3.
759
760- ``ERRATA_N2_2728475``: This applies erratum 2728475 workaround to Neoverse-N2
761   CPU, this erratum affects system configurations that do not use and ARM
762   interconnect IP. This needs to be enabled for revisions r0p0, r0p1 and r0p2.
763   It is fixed in r0p3.
764
765-  ``ERRATA_N2_2779511``: This applies errata 2779511 workaround to Neoverse-N2
766   CPU. This needs to be enabled for revisions r0p0, r0p1 and r0p2. It is fixed
767   in r0p3.
768
769-  ``ERRATA_N2_3701773``: This applies errata 3701773 workaround to Neoverse-N2
770   CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2, r0p3 and is
771   still open.
772
773For Neoverse N3, the following errata build flags are defined :
774
775-  ``ERRATA_N3_3699563``: This applies errata 3699563 workaround to Neoverse-N3
776   CPU. This needs to be enabled for revisions r0p0 and is still open.
777
778For Cortex-X2, the following errata build flags are defined :
779
780-  ``ERRATA_X2_1901946``: This applies errata 1901946 workaround to Cortex-X2
781   CPU. This needs to be enabled only for r1p0, it is fixed in r2p0.
782
783-  ``ERRATA_X2_1916945``: This applies errata 1916945 workaround to Cortex-X2
784   CPU. This needs to be enabled only for revisions r0p0 and r1p0 of the CPU, it
785   is fixed in r2p0.
786
787-  ``ERRATA_X2_1917258``: This applies errata 1917258 workaround to Cortex-X2
788   CPU. This needs to be enabled only for revisions r0p0 and r1p0 of the CPU, it
789   is fixed in r2p0.
790
791-  ``ERRATA_X2_1927200``: This applies errata 1927200 workaround to Cortex-X2
792   CPU. This needs to be enabled only for revisions r0p0 and r1p0 of the CPU, it
793   is fixed in r2p0.
794
795-  ``ERRATA_X2_1934260``: This applies errata 1934260 workaround to Cortex-X2
796   CPU. This needs to be enabled only for revision r1p0 of the CPU, it is fixed
797   in r2p0.
798
799-  ``ERRATA_X2_2002765``: This applies errata 2002765 workaround to Cortex-X2
800   CPU. This needs to be enabled only for revisions r0p0, r1p0 and r2p0 of the
801   CPU, it is fixed in r2p1.
802
803-  ``ERRATA_X2_2017096``: This applies errata 2017096 workaround to Cortex-X2
804   CPU. This needs to be enabled only for revisions r0p0, r1p0 and r2p0 of the
805   CPU, it is fixed in r2p1.
806
807-  ``ERRATA_X2_2081180``: This applies errata 2081180 workaround to Cortex-X2
808   CPU. This needs to be enabled only for revisions r0p0, r1p0 and r2p0 of the
809   CPU, it is fixed in r2p1.
810
811-  ``ERRATA_X2_2083908``: This applies errata 2083908 workaround to Cortex-X2
812   CPU. This needs to be enabled only for revision r2p0 of the CPU, it is fixed
813   in r2p1.
814
815-  ``ERRATA_X2_2136059``: This applies errata 2136059 workaround to Cortex-X2
816   CPU. This needs to be enabled only for revisions r0p0, r1p0 and r2p0 of the
817   CPU, it is fixed in r2p1.
818
819-  ``ERRATA_X2_2147715``: This applies errata 2147715 workaround to Cortex-X2
820   CPU. This needs to be enabled only for revision r2p0 of the CPU, it is fixed
821   in r2p1.
822
823-  ``ERRATA_X2_2216384``: This applies errata 2216384 workaround to Cortex-X2
824   CPU. This needs to be enabled only for revisions r0p0, r1p0 and r2p0 of the
825   CPU, it is fixed in r2p1.
826
827-  ``ERRATA_X2_2267065``: This applies errata 2267065 workaround to Cortex-X2
828   CPU. This needs to be enabled only for revisions r0p0, r1p0 and r2p0 of the
829   CPU, it is fixed in r2p1.
830
831-  ``ERRATA_X2_2282622``: This applies errata 2282622 workaround to Cortex-X2
832   CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and r2p1 of the
833   CPU and is still open.
834
835-  ``ERRATA_X2_2291219``: This applies errata 2291219 workaround to Cortex-X2
836   CPU. This needs to be enabled only for revisions r0p0, r1p0 and r2p0 of the
837   CPU, it is fixed in r2p1.
838
839-  ``ERRATA_X2_2371105``: This applies errata 2371105 workaround to Cortex-X2
840   CPU. This needs to be enabled only for revisions r0p0, r1p0 and r2p0 of the
841   CPU, it is fixed in r2p1.
842
843- ``ERRATA_X2_2701952``: This applies errata 2701952 workaround to Cortex-X2
844   CPU and affects system configurations that do not use an Arm interconnect IP.
845   This needs to be enabled for revisions r0p0, r1p0, r2p0 and r2p1 and is
846   still open.
847
848-  ``ERRATA_X2_2742423``: This applies errata 2742423 workaround to Cortex-X2
849   CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and r2p1 of the
850   CPU and is still open.
851
852-  ``ERRATA_X2_2768515``: This applies errata 2768515 workaround to Cortex-X2
853   CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and r2p1 of the
854   CPU and is still open.
855
856-  ``ERRATA_X2_2778471``: This applies errata 2778471 workaround to Cortex-X2
857   CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and r2p1 of the
858   CPU and is still open.
859
860-  ``ERRATA_X2_3701772``: This applies errata 3701772 workaround to Cortex-X2
861   CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and r2p1 of the
862   CPU and is still open.
863
864For Cortex-X3, the following errata build flags are defined :
865
866- ``ERRATA_X3_2266875``: This applies errata 2266875 workaround to the Cortex-X3
867  CPU. This needs to be enabled only for revisions r0p0 and r1p0 of the CPU, it
868  is fixed in r1p1.
869
870- ``ERRATA_X3_2302506``: This applies errata 2302506 workaround to the Cortex-X3
871  CPU. This needs to be enabled only for revisions r0p0, r1p0 and r1p1, it is
872  fixed in r1p2.
873
874- ``ERRATA_X3_2313909``: This applies errata 2313909 workaround to
875  Cortex-X3 CPU. This needs to be enabled only for revisions r0p0 and r1p0
876  of the CPU, it is fixed in r1p1.
877
878- ``ERRATA_X3_2372204``: This applies errata 2372204 workaround to
879  Cortex-X3 CPU. This needs to be enabled only for revisions r0p0 and r1p0
880  of the CPU, it is fixed in r1p1.
881
882- ``ERRATA_X3_2615812``: This applies errata 2615812 workaround to Cortex-X3
883  CPU. This needs to be enabled only for revisions r0p0, r1p0 and r1p1 of the
884  CPU, it is fixed in r1p2.
885
886- ``ERRATA_X3_2641945``: This applies errata 2641945 workaround to Cortex-X3
887  CPU. This needs to be enabled only for revisions r0p0 and r1p0 of the CPU.
888  It is fixed in r1p1.
889
890- ``ERRATA_X3_2701951``: This applies erratum 2701951 workaround to Cortex-X3
891  CPU and affects system configurations that do not use an ARM interconnect
892  IP. This needs to be applied to revisions r0p0, r1p0 and r1p1. It is fixed
893  in r1p2.
894
895- ``ERRATA_X3_2742421``: This applies errata 2742421 workaround to
896  Cortex-X3 CPU. This needs to be enabled only for revisions r0p0, r1p0 and
897  r1p1. It is fixed in r1p2.
898
899- ``ERRATA_X3_2743088``: This applies errata 2743088 workaround to Cortex-X3
900  CPU. This needs to be enabled only for revisions r0p0, r1p0 and r1p1. It is
901  fixed in r1p2.
902
903- ``ERRATA_X3_2779509``: This applies errata 2779509 workaround to Cortex-X3
904  CPU. This needs to be enabled only for revisions r0p0, r1p0 and r1p1 of the
905  CPU. It is fixed in r1p2.
906
907- ``ERRATA_X3_3213672``: This applies errata 3213672 workaround to Cortex-X3
908  CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1 and r1p2
909  of the CPU. It is still open.
910
911- ``ERRATA_X3_3692984``: This applies errata 3692984 workaround to Cortex-X3
912  CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1 and r1p2
913  of the CPU. It is still open.
914
915- ``ERRATA_X3_3701769``: This applies errata 3701769 workaround to Cortex-X3
916  CPU. This needs to be enabled only for revisions r0p0, r1p0, r1p1 and r1p2
917  of the CPU and it is still open.
918
919- ``ERRATA_X3_3827463``: This applies errata 3827463 workaround to Cortex-X3
920  CPU. This needs to be enabled only for revisions r0p0, r1p0 and r1p1 of
921  the CPU. It is fixed in r1p2.
922
923For Cortex-X4, the following errata build flags are defined :
924
925- ``ERRATA_X4_2701112``: This applies erratum 2701112 workaround to Cortex-X4
926  CPU and affects system configurations that do not use an Arm interconnect IP.
927  This needs to be enabled for revisions r0p0 and is fixed in r0p1.
928  The workaround for this erratum is not implemented in EL3, but the flag can
929  be enabled/disabled at the platform level. The flag is used when the errata ABI
930  feature is enabled and can assist the Kernel in the process of
931  mitigation of the erratum.
932
933- ``ERRATA_X4_2726228``: This applies erratum 2726228 workaround to Cortex-X4
934  CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in
935  r0p2.
936
937-  ``ERRATA_X4_2740089``: This applies errata 2740089 workaround to Cortex-X4
938   CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed
939   in r0p2.
940
941- ``ERRATA_X4_2763018``: This applies errata 2763018 workaround to Cortex-X4
942  CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in r0p2.
943
944- ``ERRATA_X4_2816013``: This applies errata 2816013 workaround to Cortex-X4
945  CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in r0p2.
946
947- ``ERRATA_X4_2897503``: This applies errata 2897503 workaround to Cortex-X4
948  CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in r0p2.
949
950- ``ERRATA_X4_2923985``: This applies errata 2923985 workaround to Cortex-X4
951  CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in r0p2.
952
953- ``ERRATA_X4_2957258``: This applies errata 2957258 workaround to Cortex-X4
954  CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in r0p2.
955
956- ``ERRATA_X4_3076789``: This applies errata 3076789 workaround to Cortex-X4
957  CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in r0p2.
958
959- ``ERRATA_X4_3133195``: This applies errata 3133195 workaround to Cortex-X4
960  CPU. This needs to be enabled for revision r0p2. It is fixed in r0p3.
961
962- ``ERRATA_X4_3701758``: This applies errata 3701758 workaround to Cortex-X4
963  CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2 and r0p3.
964  It is still open.
965
966- ``ERRATA_X4_3887999``: This applies errata 3887999 workaround to Cortex-X4
967  CPU. This needs to be enabled for revision r0p0, r0p1, r0p2 and r0p3.
968  It is still open.
969
970For Cortex-X925, the following errata build flags are defined :
971
972- ``ERRATA_X925_2963999``: This applies errata 2963999 workaround to Cortex-X925
973  CPU. This needs to be enabled for revision r0p0. It is fixed in r0p1.
974
975- ``ERRATA_X925_3701747``: This applies errata 3701747 workaround to Cortex-X925
976  CPU. This needs to be enabled for revisions r0p0 and r0p1. It is still open.
977
978For Cortex-A510, the following errata build flags are defined :
979
980-  ``ERRATA_A510_2008766``: This applies errata 2008766 workaround to
981   Cortex-A510 CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2,
982   r0p3, r1p0, r1p1, r1p2 and r1p3. It is still open.
983
984-  ``ERRATA_A510_2288014``: This applies errata 2288014 workaround to
985   Cortex-A510 CPU. This needs to be enabled only for revisions r0p0, r0p1,
986   r0p2, r0p3 and r1p0, it is fixed in r1p1.
987
988-  ``ERRATA_A510_2042739``: This applies errata 2042739 workaround to
989   Cortex-A510 CPU. This needs to be enabled only for revisions r0p0, r0p1 and
990   r0p2, it is fixed in r0p3.
991
992-  ``ERRATA_A510_2041909``: This applies errata 2041909 workaround to
993   Cortex-A510 CPU. This needs to be enabled only for revision r0p2 and is fixed
994   in r0p3. The issue is also present in r0p0 and r0p1 but there is no
995   workaround for those revisions.
996
997-  ``ERRATA_A510_2080326``: This applies errata 2080326 workaround to
998   Cortex-A510 CPU. This needs to be enabled only for revision r0p2 and is
999   fixed in r0p3. This issue is also present in r0p0 and r0p1 but there is no
1000   workaround for those revisions.
1001
1002-  ``ERRATA_A510_2169012``: This applies errata 2169012 workaround to
1003   Cortex-A510 CPU. This needs to be enabled only for revisions r0p0, r0p1,
1004   r0p2, r0p3 and r1p0, it is fixed in r1p1.
1005
1006-  ``ERRATA_A510_2218134``: This applies errata 2218134 workaround to
1007   Cortex-A510 CPU. This needs to be enabled only for revision r1p0 and is fixed
1008   in r1p1.
1009
1010-  ``ERRATA_A510_2250311``: This applies errata 2250311 workaround to
1011   Cortex-A510 CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2,
1012   r0p3 and r1p0, it is fixed in r1p1. This workaround disables MPMM even if
1013   ENABLE_MPMM=1.
1014
1015-  ``ERRATA_A510_2218950``: This applies errata 2218950 workaround to
1016   Cortex-A510 CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2,
1017   r0p3 and r1p0, it is fixed in r1p1.
1018
1019-  ``ERRATA_A510_2172148``: This applies errata 2172148 workaround to
1020   Cortex-A510 CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2,
1021   r0p3 and r1p0, it is fixed in r1p1.
1022
1023-  ``ERRATA_A510_2347730``: This applies errata 2347730 workaround to
1024   Cortex-A510 CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2,
1025   r0p3, r1p0 and r1p1. It is fixed in r1p2.
1026
1027-  ``ERRATA_A510_2371937``: This applies errata 2371937 workaround to
1028   Cortex-A510 CPU. This needs to applied for revisions r0p0, r0p1, r0p2,
1029   r0p3, r1p0, r1p1, and is fixed in r1p2.
1030
1031-  ``ERRATA_A510_2420992``: This applies errata 2420992 workaround to
1032   Cortex-A510 CPU. This needs to applied for revisions r1p0 and r1p1, and is
1033   fixed in r1p2.
1034
1035-  ``ERRATA_A510_2666669``: This applies errata 2666669 workaround to
1036   Cortex-A510 CPU. This needs to applied for revisions r0p0, r0p1, r0p2,
1037   r0p3, r1p0, r1p1. It is fixed in r1p2.
1038
1039-  ``ERRATA_A510_2684597``: This applies erratum 2684597 workaround to
1040   Cortex-A510 CPU. This needs to be applied to revision r0p0, r0p1, r0p2,
1041   r0p3, r1p0, r1p1 and r1p2. It is fixed in r1p3.
1042
1043-  ``ERRATA_A510_2971420``: This applies erratum 2971420 workaround to
1044   Cortex-A510 CPU. This needs to be applied to revisions r0p1, r0p2, r0p3,
1045   r1p0, r1p1, r1p2 and r1p3 and is still open.
1046
1047-  ``ERRATA_A510_3672349``: This applies erratum 3672349 workaround to
1048   Cortex-A510 CPU. This needs to be applied to revisions r0p1, r0p2, r0p3,
1049   r1p0, r1p1, r1p2 and r1p3 and is still open.
1050
1051-  ``ERRATA_A510_3704847``: This applies erratum 3704847 workaround to
1052   Cortex-A510 CPU. This needs to be applied to revisions r0p1, r0p2, r0p3,
1053   r1p0, r1p1, r1p2 and r1p3 and is still open.
1054
1055For Cortex-A520, the following errata build flags are defined :
1056
1057-  ``ERRATA_A520_2630792``: This applies errata 2630792 workaround to
1058   Cortex-A520 CPU. This needs to applied for revisions r0p0, r0p1 of the
1059   CPU and is still open.
1060
1061-  ``ERRATA_A520_2858100``: This applies errata 2858100 workaround to
1062   Cortex-A520 CPU. This needs to be enabled for revisions r0p0 and r0p1.
1063   It is still open.
1064
1065-  ``ERRATA_A520_2938996``: This applies errata 2938996 workaround to
1066   Cortex-A520 CPU. This needs to be enabled for revisions r0p0 and r0p1.
1067   It is fixed in r0p2.
1068
1069For Cortex-A715, the following errata build flags are defined :
1070
1071-  ``ERRATA_A715_2331818``: This applies errata 2331818 workaround to
1072   Cortex-A715 CPU. This needs to be enabled for revisions r0p0 and r1p0.
1073   It is fixed in r1p1.
1074
1075- ``ERRATA_A715_2344187``: This applies errata 2344187 workaround to
1076   Cortex-A715 CPU. This needs to be enabled for revisions r0p0 and r1p0. It is
1077   fixed in r1p1.
1078
1079-  ``ERRATA_A715_2376701``: This applies errata 2376701 workaround to
1080   Cortex-A715 CPU. This needs to be enabled for revisions r0p0 and r1p0. It is
1081   fixed in r1p1.
1082
1083-  ``ERRATA_A715_2409570``: This applies errata 2409570 workaround to
1084   Cortex-A715 CPU. This needs to be enabled only for revision r1p0.
1085   It is fixed in r1p1. This errata also applies to r0p0 but that revision has a
1086   different workaround, and since r0p0 is not used in production hardware it is
1087   not implemented.
1088
1089-  ``ERRATA_A715_2413290``: This applies errata 2413290 workaround to
1090   Cortex-A715 CPU. This needs to be enabled only for revision r1p0 and
1091   when SPE(Statistical profiling extension)=True. The errata is fixed
1092   in r1p1.
1093
1094-  ``ERRATA_A715_2420947``: This applies errata 2420947 workaround to
1095   Cortex-A715 CPU. This needs to be enabled only for revision r1p0.
1096   It is fixed in r1p1.
1097
1098-  ``ERRATA_A715_2429384``: This applies errata 2429384 workaround to
1099   Cortex-A715 CPU. This needs to be enabled for revision r1p0. There is no
1100   workaround for revision r0p0. It is fixed in r1p1.
1101
1102-  ``ERRATA_A715_2561034``: This applies errata 2561034 workaround to
1103   Cortex-A715 CPU. This needs to be enabled only for revision r1p0.
1104   It is fixed in r1p1.
1105
1106-  ``ERRATA_A715_2728106``: This applies errata 2728106 workaround to
1107   Cortex-A715 CPU. This needs to be enabled for revisions r0p0, r1p0
1108   and r1p1. It is fixed in r1p2.
1109
1110-  ``ERRATA_A715_2804830``: This applies errata 2804830 workaround to
1111   Cortex-A715 CPU. This needs to be enabled for revisions r0p0, r1p0,
1112   r1p1 and r1p2. It is fixed in r1p3.
1113
1114-  ``ERRATA_A715_3699560``: This applies errata 3699560 workaround to
1115   Cortex-A715 CPU. This needs to be enabled for revisions r0p0, r1p0,
1116   r1p2 and r1p3. It is still open.
1117
1118-  ``ERRATA_A715_3711916``: This applies errata 3711916 workaround to
1119   Cortex-A715 CPU. This needs to be enabled for revisions r0p0, r1p0,
1120   r1p1, r1p2 and r1p3. It is still open.
1121
1122For Cortex-A720, the following errata build flags are defined :
1123
1124-  ``ERRATA_A720_2729604``: This applies errata 2729604 workaround to
1125   Cortex-A720 CPU. This needs to be enabled for revisions r0p0 and r0p1.
1126   It is fixed in r0p2.
1127
1128-  ``ERRATA_A720_2792132``: This applies errata 2792132 workaround to
1129   Cortex-A720 CPU. This needs to be enabled for revisions r0p0 and r0p1.
1130   It is fixed in r0p2.
1131
1132-  ``ERRATA_A720_2844092``: This applies errata 2844092 workaround to
1133   Cortex-A720 CPU. This needs to be enabled for revisions r0p0 and r0p1.
1134   It is fixed in r0p2.
1135
1136-  ``ERRATA_A720_2926083``: This applies errata 2926083 workaround to
1137   Cortex-A720 CPU. This needs to be enabled for revisions r0p0 and r0p1.
1138   It is fixed in r0p2.
1139
1140-  ``ERRATA_A720_2940794``: This applies errata 2940794 workaround to
1141   Cortex-A720 CPU. This needs to be enabled for revisions r0p0 and r0p1.
1142   It is fixed in r0p2.
1143
1144-  ``ERRATA_A720_3699561``: This applies errata 3699561 workaround to
1145   Cortex-A720 CPU. This needs to be enabled for revisions r0p0, r0p1
1146   and r0p2. It is still open.
1147
1148-  ``ERRATA_A720_3711910``: This applies errata 3711910 workaround to
1149   Cortex-A720 CPU. This needs to be enabled for revisions r0p0, r0p1
1150   and r0p2. It is still open.
1151
1152For Cortex-A720_AE, the following errata build flags are defined :
1153
1154-  ``ERRATA_A720_AE_3699562``: This applies errata 3699562 workaround
1155   to Cortex-A720_AE CPU. This needs to be enabled for revisions r0p0.
1156   It is still open.
1157
1158For Cortex-A725, the following errata build flags are defined :
1159
1160-  ``ERRATA_A725_3699564``: This applies errata 3699564 workaround to
1161   Cortex-A725 CPU. This needs to be enabled for revisions r0p0 and r0p1.
1162   It is fixed in r0p2.
1163
1164DSU Errata Workarounds
1165----------------------
1166
1167Similar to CPU errata, TF-A also implements workarounds for DSU (DynamIQ
1168Shared Unit) errata. The DSU errata details can be found in the respective Arm
1169documentation:
1170
1171- `Arm DSU Software Developers Errata Notice`_.
1172
1173Each erratum is identified by an ``ID``, as defined in the DSU errata notice
1174document. Thus, the build flags which enable/disable the errata workarounds
1175have the format ``ERRATA_DSU_<ID>``. The implementation and application logic
1176of DSU errata workarounds are similar to `CPU errata workarounds`_.
1177
1178For DSU errata, the following build flags are defined:
1179
1180-  ``ERRATA_DSU_798953``: This applies errata 798953 workaround for the
1181   affected DSU configurations. This errata applies only for those DSUs that
1182   revision is r0p0 (on r0p1 it is fixed). However, please note that this
1183   workaround results in increased DSU power consumption on idle.
1184
1185-  ``ERRATA_DSU_936184``: This applies errata 936184 workaround for the
1186   affected DSU configurations. This errata applies only for those DSUs that
1187   contain the ACP interface **and** the DSU revision is older than r2p0 (on
1188   r2p0 it is fixed). However, please note that this workaround results in
1189   increased DSU power consumption on idle.
1190
1191-  ``ERRATA_DSU_2313941``: This applies errata 2313941 workaround for the
1192   affected DSU configurations. This errata applies for those DSUs with
1193   revisions r0p0, r1p0, r2p0, r2p1, r3p0, r3p1 and is still open. However,
1194   please note that this workaround results in increased DSU power consumption
1195   on idle.
1196
1197-  ``ERRATA_DSU_2900952``: This applies errata 2900952 workaround for the
1198   affected DSU-120 configurations. This erratum applies to some r2p0
1199   implementations and is fixed in r2p1. The affected r2p0 implementations
1200   are determined by reading the IMP_CLUSTERREVIDR_EL1[1] register bit
1201   and making sure it's clear.
1202
1203CPU Specific optimizations
1204--------------------------
1205
1206This section describes some of the optimizations allowed by the CPU micro
1207architecture that can be enabled by the platform as desired.
1208
1209-  ``SKIP_A57_L1_FLUSH_PWR_DWN``: This flag enables an optimization in the
1210   Cortex-A57 cluster power down sequence by not flushing the Level 1 data
1211   cache. The L1 data cache and the L2 unified cache are inclusive. A flush
1212   of the L2 by set/way flushes any dirty lines from the L1 as well. This
1213   is a known safe deviation from the Cortex-A57 TRM defined power down
1214   sequence. Each Cortex-A57 based platform must make its own decision on
1215   whether to use the optimization.
1216
1217-  ``A53_DISABLE_NON_TEMPORAL_HINT``: This flag disables the cache non-temporal
1218   hint. The LDNP/STNP instructions as implemented on Cortex-A53 do not behave
1219   in a way most programmers expect, and will most probably result in a
1220   significant speed degradation to any code that employs them. The Armv8-A
1221   architecture (see Arm DDI 0487A.h, section D3.4.3) allows cores to ignore
1222   the non-temporal hint and treat LDNP/STNP as LDP/STP instead. Enabling this
1223   flag enforces this behaviour. This needs to be enabled only for revisions
1224   <= r0p3 of the CPU and is enabled by default.
1225
1226-  ``A57_DISABLE_NON_TEMPORAL_HINT``: This flag has the same behaviour as
1227   ``A53_DISABLE_NON_TEMPORAL_HINT`` but for Cortex-A57. This needs to be
1228   enabled only for revisions <= r1p2 of the CPU and is enabled by default,
1229   as recommended in section "4.7 Non-Temporal Loads/Stores" of the
1230   `Cortex-A57 Software Optimization Guide`_.
1231
1232- ''A57_ENABLE_NON_CACHEABLE_LOAD_FWD'': This flag enables non-cacheable
1233   streaming enhancement feature for Cortex-A57 CPUs. Platforms can set
1234   this bit only if their memory system meets the requirement that cache
1235   line fill requests from the Cortex-A57 processor are atomic. Each
1236   Cortex-A57 based platform must make its own decision on whether to use
1237   the optimization. This flag is disabled by default.
1238
1239-  ``NEOVERSE_Nx_EXTERNAL_LLC``: This flag indicates that an external last
1240   level cache(LLC) is present in the system, and that the DataSource field
1241   on the master CHI interface indicates when data is returned from the LLC.
1242   This is used to control how the LL_CACHE* PMU events count.
1243   Default value is 0 (Disabled).
1244
1245-  ``NEOVERSE_N2_PREFETCHER_DISABLE``: This flag disables the region prefetcher
1246   on the Neoverse N2 core. This is used during performance analysis to get clean
1247   and repeatable measurements of the cache by preventing speculative data fetches
1248   from interfering with benchmark results.
1249   Default value is 0 (Disabled).
1250
1251GIC Errata Workarounds
1252----------------------
1253-  ``GIC600_ERRATA_WA_2384374``: This flag applies part 2 of errata 2384374
1254   workaround for the affected GIC600 and GIC600-AE implementations. It applies
1255   to implementations of GIC600 and GIC600-AE with revisions less than or equal
1256   to r1p6 and r0p2 respectively. If the platform sets GICV3_SUPPORT_GIC600,
1257   then this flag is enabled; otherwise, it is 0 (Disabled).
1258
1259--------------
1260
1261*Copyright (c) 2014-2025, Arm Limited and Contributors. All rights reserved.*
1262
1263.. _CVE-2017-5715: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-5715
1264.. _CVE-2018-3639: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-3639
1265.. _CVE-2022-23960: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-23960
1266.. _Cortex-A72 MPCore Software Developers Errata Notice: https://developer.arm.com/documentation/epm012079/latest
1267.. _Cortex-A57 Software Optimization Guide: https://developer.arm.com/documentation/uan0015
1268.. _Arm DSU Software Developers Errata Notice: https://developer.arm.com/documentation/SDEN854652
1269