xref: /rk3399_ARM-atf/docs/design/cpu-specific-build-macros.rst (revision 16de9fae932cd7b86e1aaaf73b34ff7a379e19fe)
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-A72, the following errata build flags are defined :
206
207-  ``ERRATA_A72_859971``: This applies errata 859971 workaround to Cortex-A72
208   CPU. This needs to be enabled only for revision <= r0p3 of the CPU.
209
210-  ``ERRATA_A72_1319367``: This applies errata 1319367 workaround to all
211   revisions of Cortex-A72 CPU.
212
213For Cortex-A73, the following errata build flags are defined :
214
215-  ``ERRATA_A73_852427``: This applies errata 852427 workaround to Cortex-A73
216   CPU. This needs to be enabled only for revision r0p0 of the CPU.
217
218-  ``ERRATA_A73_855423``: This applies errata 855423 workaround to Cortex-A73
219   CPU. This needs to be enabled only for revision <= r0p1 of the CPU.
220
221For Cortex-A75, the following errata build flags are defined :
222
223-  ``ERRATA_A75_764081``: This applies errata 764081 workaround to Cortex-A75
224   CPU. This needs to be enabled only for revision r0p0 of the CPU.
225
226-  ``ERRATA_A75_790748``: This applies errata 790748 workaround to Cortex-A75
227    CPU. This needs to be enabled only for revision r0p0 of the CPU.
228
229For Cortex-A76, the following errata build flags are defined :
230
231-  ``ERRATA_A76_1073348``: This applies errata 1073348 workaround to Cortex-A76
232   CPU. This needs to be enabled only for revision <= r1p0 of the CPU.
233
234-  ``ERRATA_A76_1130799``: This applies errata 1130799 workaround to Cortex-A76
235   CPU. This needs to be enabled only for revision <= r2p0 of the CPU.
236
237-  ``ERRATA_A76_1220197``: This applies errata 1220197 workaround to Cortex-A76
238   CPU. This needs to be enabled only for revision <= r2p0 of the CPU.
239
240-  ``ERRATA_A76_1257314``: This applies errata 1257314 workaround to Cortex-A76
241   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
242
243-  ``ERRATA_A76_1262606``: This applies errata 1262606 workaround to Cortex-A76
244   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
245
246-  ``ERRATA_A76_1262888``: This applies errata 1262888 workaround to Cortex-A76
247   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
248
249-  ``ERRATA_A76_1275112``: This applies errata 1275112 workaround to Cortex-A76
250   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
251
252-  ``ERRATA_A76_1791580``: This applies errata 1791580 workaround to Cortex-A76
253   CPU. This needs to be enabled only for revision <= r4p0 of the CPU.
254
255-  ``ERRATA_A76_1165522``: This applies errata 1165522 workaround to all
256   revisions of Cortex-A76 CPU. This errata is fixed in r3p0 but due to
257   limitation of errata framework this errata is applied to all revisions
258   of Cortex-A76 CPU.
259
260-  ``ERRATA_A76_1868343``: This applies errata 1868343 workaround to Cortex-A76
261   CPU. This needs to be enabled only for revision <= r4p0 of the CPU.
262
263-  ``ERRATA_A76_1946160``: This applies errata 1946160 workaround to Cortex-A76
264   CPU. This needs to be enabled only for revisions r3p0 - r4p1 of the CPU.
265
266-  ``ERRATA_A76_2743102``: This applies errata 2743102 workaround to Cortex-A76
267   CPU. This needs to be enabled for all revisions <= r4p1 of the CPU and is
268   still open.
269
270For Cortex-A76AE, the following errata build flags are defined :
271
272-  ``ERRATA_A76AE_1931427``: This applies errata 1931427 workaround to Cortex-A76AE
273   CPU. This needs to be enabled for revision r0p0 and r1p0 of the CPU and it is
274   fixed in r1p1.
275
276-  ``ERRATA_A76AE_1931435``: This applies errata 1931435 workaround to Cortex-A76AE
277   CPU. This needs to be enabled for revision r0p0 and r1p0 of the CPU and it is
278   fixed in r1p1.
279
280For Cortex-A77, the following errata build flags are defined :
281
282-  ``ERRATA_A77_1508412``: This applies errata 1508412 workaround to Cortex-A77
283   CPU. This needs to be enabled only for revision <= r1p0 of the CPU.
284
285-  ``ERRATA_A77_1925769``: This applies errata 1925769 workaround to Cortex-A77
286   CPU. This needs to be enabled only for revision <= r1p1 of the CPU.
287
288-  ``ERRATA_A77_1946167``: This applies errata 1946167 workaround to Cortex-A77
289   CPU. This needs to be enabled only for revision <= r1p1 of the CPU.
290
291-  ``ERRATA_A77_1791578``: This applies errata 1791578 workaround to Cortex-A77
292   CPU. This needs to be enabled for r0p0, r1p0, and r1p1, it is still open.
293
294-  ``ERRATA_A77_2356587``: This applies errata 2356587 workaround to Cortex-A77
295   CPU. This needs to be enabled for r0p0, r1p0, and r1p1, it is still open.
296
297 -  ``ERRATA_A77_1800714``: This applies errata 1800714 workaround to Cortex-A77
298    CPU. This needs to be enabled for revisions <= r1p1 of the CPU.
299
300 -  ``ERRATA_A77_2743100``: This applies errata 2743100 workaround to Cortex-A77
301    CPU. This needs to be enabled for r0p0, r1p0, and r1p1, it is still open.
302
303For Cortex-A78, the following errata build flags are defined :
304
305-  ``ERRATA_A78_1688305``: This applies errata 1688305 workaround to Cortex-A78
306   CPU. This needs to be enabled only for revision r0p0 - r1p0 of the CPU.
307
308-  ``ERRATA_A78_1941498``: This applies errata 1941498 workaround to Cortex-A78
309   CPU. This needs to be enabled for revisions r0p0, r1p0, and r1p1 of the CPU.
310
311-  ``ERRATA_A78_1951500``: This applies errata 1951500 workaround to Cortex-A78
312   CPU. This needs to be enabled for revisions r1p0 and r1p1, r0p0 has the same
313   issue but there is no workaround for that revision.
314
315-  ``ERRATA_A78_1821534``: This applies errata 1821534 workaround to Cortex-A78
316   CPU. This needs to be enabled for revisions r0p0 and r1p0.
317
318-  ``ERRATA_A78_1952683``: This applies errata 1952683 workaround to Cortex-A78
319   CPU. This needs to be enabled for revision r0p0, it is fixed in r1p0.
320
321-  ``ERRATA_A78_2242635``: This applies errata 2242635 workaround to Cortex-A78
322   CPU. This needs to be enabled for revisions r1p0, r1p1, and r1p2. The issue
323   is present in r0p0 but there is no workaround. It is still open.
324
325-  ``ERRATA_A78_2376745``: This applies errata 2376745 workaround to Cortex-A78
326   CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1, and r1p2, and
327   it is still open.
328
329-  ``ERRATA_A78_2395406``: This applies errata 2395406 workaround to Cortex-A78
330   CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1, and r1p2, and
331   it is still open.
332
333- ``ERRATA_A78_2712571``: This applies erratum 2712571 workaround to Cortex-A78
334   CPU, this erratum affects system configurations that do not use an ARM
335   interconnect IP. This needs to be enabled for revisions r0p0, r1p0, r1p1
336   and r1p2 and it is still open.
337
338-  ``ERRATA_A78_2742426``: This applies erratum 2742426 workaround to Cortex-A78
339   CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1 and r1p2 and
340   it is still open.
341
342-  ``ERRATA_A78_2772019``: This applies errata 2772019 workaround to Cortex-A78
343   CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1, and r1p2, and
344   it is still open.
345
346-  ``ERRATA_A78_2779479``: This applies erratum 2779479 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
350For Cortex-A78AE, the following errata build flags are defined :
351
352- ``ERRATA_A78_AE_1941500`` : This applies errata 1941500 workaround to
353   Cortex-A78AE CPU. This needs to be enabled for revisions r0p0 and r0p1.
354   This erratum is still open.
355
356- ``ERRATA_A78_AE_1951502`` : This applies errata 1951502 workaround to
357  Cortex-A78AE CPU. This needs to be enabled for revisions r0p0 and r0p1. This
358  erratum is still open.
359
360- ``ERRATA_A78_AE_2376748`` : This applies errata 2376748 workaround to
361  Cortex-A78AE CPU. This needs to be enabled for revisions r0p0, r0p1 and r0p2.
362  This erratum is still open.
363
364- ``ERRATA_A78_AE_2395408`` : This applies errata 2395408 workaround to
365  Cortex-A78AE CPU. This needs to be enabled for revisions r0p0 and r0p1. This
366  erratum is still open.
367
368- ``ERRATA_A78_AE_2712574`` : This applies erratum 2712574 workaround to
369  Cortex-A78AE CPU. This erratum affects system configurations that do not use
370  an ARM interconnect IP. This needs to be enabled for revisions r0p0, r0p1 and
371  r0p2. This erratum is still open.
372
373For Cortex-A78C, the following errata build flags are defined :
374
375- ``ERRATA_A78C_1827430`` : This applies errata 1827430 workaround to
376  Cortex-A78C CPU. This needs to be enabled for revision r0p0. The erratum is
377  fixed in r0p1.
378
379- ``ERRATA_A78C_1827440`` : This applies errata 1827440 workaround to
380  Cortex-A78C CPU. This needs to be enabled for revision r0p0. The erratum is
381  fixed in r0p1.
382
383- ``ERRATA_A78C_2242638`` : This applies errata 2242638 workaround to
384  Cortex-A78C CPU. This needs to be enabled for revisions r0p1, r0p2 and
385  it is still open.
386
387- ``ERRATA_A78C_2376749`` : This applies errata 2376749 workaround to
388  Cortex-A78C CPU. This needs to be enabled for revisions r0p1 and r0p2. This
389  erratum is still open.
390
391- ``ERRATA_A78C_2395411`` : This applies errata 2395411 workaround to
392  Cortex-A78C CPU. This needs to be enabled for revisions r0p1 and r0p2. This
393  erratum is still open.
394
395- ``ERRATA_A78C_2683027`` : This applies errata 2683027 workaround to
396  Cortex-A78C CPU. This needs to be enabled for revisions r0p1 and r0p2. This
397  erratum is still open.
398
399- ``ERRATA_A78C_2712575`` : This applies erratum 2712575 workaround to
400  Cortex-A78C CPU, this erratum affects system configurations that do not use
401  an ARM interconnect IP. This needs to be enabled for revisions r0p1 and r0p2
402  and is still open.
403
404- ``ERRATA_A78C_2743232`` : This applies erratum 2743232 workaround to
405  Cortex-A78C CPU. This needs to be enabled for revisions r0p1 and r0p2.
406  This erratum is still open.
407
408- ``ERRATA_A78C_2772121`` : This applies errata 2772121 workaround to
409  Cortex-A78C CPU. This needs to be enabled for revisions r0p0, r0p1 and r0p2.
410  This erratum is still open.
411
412- ``ERRATA_A78C_2779484`` : This applies errata 2779484 workaround to
413  Cortex-A78C CPU. This needs to be enabled for revisions r0p1 and r0p2.
414  This erratum is still open.
415
416For Cortex-X1 CPU, the following errata build flags are defined:
417
418- ``ERRATA_X1_1821534`` : This applies errata 1821534 workaround to Cortex-X1
419   CPU. This needs to be enabled only for revision <= r1p0 of the CPU.
420
421- ``ERRATA_X1_1688305`` : This applies errata 1688305 workaround to Cortex-X1
422   CPU. This needs to be enabled only for revision <= r1p0 of the CPU.
423
424- ``ERRATA_X1_1827429`` : This applies errata 1827429 workaround to Cortex-X1
425   CPU. This needs to be enabled only for revision <= r1p0 of the CPU.
426
427For Neoverse N1, the following errata build flags are defined :
428
429-  ``ERRATA_N1_1073348``: This applies errata 1073348 workaround to Neoverse-N1
430   CPU. This needs to be enabled only for revision r0p0 and r1p0 of the CPU.
431
432-  ``ERRATA_N1_1130799``: This applies errata 1130799 workaround to Neoverse-N1
433   CPU. This needs to be enabled only for revision <= r2p0 of the CPU.
434
435-  ``ERRATA_N1_1165347``: This applies errata 1165347 workaround to Neoverse-N1
436   CPU. This needs to be enabled only for revision <= r2p0 of the CPU.
437
438-  ``ERRATA_N1_1207823``: This applies errata 1207823 workaround to Neoverse-N1
439   CPU. This needs to be enabled only for revision <= r2p0 of the CPU.
440
441-  ``ERRATA_N1_1220197``: This applies errata 1220197 workaround to Neoverse-N1
442   CPU. This needs to be enabled only for revision <= r2p0 of the CPU.
443
444-  ``ERRATA_N1_1257314``: This applies errata 1257314 workaround to Neoverse-N1
445   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
446
447-  ``ERRATA_N1_1262606``: This applies errata 1262606 workaround to Neoverse-N1
448   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
449
450-  ``ERRATA_N1_1262888``: This applies errata 1262888 workaround to Neoverse-N1
451   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
452
453-  ``ERRATA_N1_1275112``: This applies errata 1275112 workaround to Neoverse-N1
454   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
455
456-  ``ERRATA_N1_1315703``: This applies errata 1315703 workaround to Neoverse-N1
457   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
458
459-  ``ERRATA_N1_1542419``: This applies errata 1542419 workaround to Neoverse-N1
460   CPU. This needs to be enabled only for revisions r3p0 - r4p0 of the CPU.
461
462-  ``ERRATA_N1_1868343``: This applies errata 1868343 workaround to Neoverse-N1
463   CPU. This needs to be enabled only for revision <= r4p0 of the CPU.
464
465-  ``ERRATA_N1_1946160``: This applies errata 1946160 workaround to Neoverse-N1
466   CPU. This needs to be enabled for revisions r3p0, r3p1, r4p0, and r4p1, for
467   revisions r0p0, r1p0, and r2p0 there is no workaround.
468
469-  ``ERRATA_N1_2743102``: This applies errata 2743102 workaround to Neoverse-N1
470   CPU. This needs to be enabled for all revisions <= r4p1 of the CPU and is
471   still open.
472
473For Neoverse V1, the following errata build flags are defined :
474
475-  ``ERRATA_V1_1618635``: This applies errata 1618635 workaround to Neoverse-V1
476   CPU. This needs to be enabled for revision r0p0 of the CPU, it is fixed in
477   r1p0.
478
479-  ``ERRATA_V1_1774420``: This applies errata 1774420 workaround to Neoverse-V1
480   CPU. This needs to be enabled only for revisions r0p0 and r1p0, it is fixed
481   in r1p1.
482
483-  ``ERRATA_V1_1791573``: This applies errata 1791573 workaround to Neoverse-V1
484   CPU. This needs to be enabled only for revisions r0p0 and r1p0, it is fixed
485   in r1p1.
486
487-  ``ERRATA_V1_1852267``: This applies errata 1852267 workaround to Neoverse-V1
488   CPU. This needs to be enabled only for revisions r0p0 and r1p0, it is fixed
489   in r1p1.
490
491-  ``ERRATA_V1_1925756``: This applies errata 1925756 workaround to Neoverse-V1
492   CPU. This needs to be enabled for r0p0, r1p0, and r1p1, it is still open.
493
494-  ``ERRATA_V1_1940577``: This applies errata 1940577 workaround to Neoverse-V1
495   CPU. This needs to be enabled only for revision r1p0 and r1p1 of the
496   CPU.
497
498-  ``ERRATA_V1_1966096``: This applies errata 1966096 workaround to Neoverse-V1
499   CPU. This needs to be enabled for revisions r1p0 and r1p1 of the CPU, the
500   issue is present in r0p0 as well but there is no workaround for that
501   revision.  It is still open.
502
503-  ``ERRATA_V1_2139242``: This applies errata 2139242 workaround to Neoverse-V1
504   CPU. This needs to be enabled for revisions r0p0, r1p0, and r1p1 of the
505   CPU.  It is still open.
506
507-  ``ERRATA_V1_2216392``: This applies errata 2216392 workaround to Neoverse-V1
508   CPU. This needs to be enabled for revisions r1p0 and r1p1 of the CPU, the
509   issue is present in r0p0 as well but there is no workaround for that
510   revision.  It is still open.
511
512-  ``ERRATA_V1_2294912``: This applies errata 2294912 workaround to Neoverse-V1
513   CPU. This needs to be enabled for revisions r0p0, r1p0, and r1p1 and r1p2 of
514   the CPU.
515
516-  ``ERRATA_V1_2348377``: This applies errata 2348377 workaroud to Neoverse-V1
517   CPU. This needs to be enabled for revisions r0p0, r1p0 and r1p1 of the CPU.
518   It has been fixed in r1p2.
519
520-  ``ERRATA_V1_2372203``: This applies errata 2372203 workaround to Neoverse-V1
521   CPU. This needs to be enabled for revisions r0p0, r1p0 and r1p1 of the CPU.
522   It is still open.
523
524- ``ERRATA_V1_2701953``: This applies erratum 2701953 workaround to Neoverse-V1
525   CPU, this erratum affects system configurations that do not use an ARM
526   interconnect IP. This needs to be enabled for revisions r0p0, r1p0 and r1p1.
527   It has been fixed in r1p2.
528
529-  ``ERRATA_V1_2743093``: This applies errata 2743093 workaround to Neoverse-V1
530   CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1 and r1p2 of the
531   CPU. It is still open.
532
533-  ``ERRATA_V1_2743233``: This applies erratum 2743233 workaround to Neoverse-V1
534   CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1, and r1p2 of the
535   CPU. It is still open.
536
537-  ``ERRATA_V1_2779461``: This applies erratum 2779461 workaround to Neoverse-V1
538   CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1, r1p2 of the
539   CPU. It is still open.
540
541For Neoverse V2, the following errata build flags are defined :
542
543-  ``ERRATA_V2_2618597``: This applies errata 2618597 workaround to Neoverse-V2
544   CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in
545   r0p2.
546
547-  ``ERRATA_V2_2662553``: This applies errata 2662553 workaround to Neoverse-V2
548   CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in
549   r0p2.
550
551-  ``ERRATA_V2_2719103``: This applies errata 2719103 workaround to Neoverse-V2
552   CPU, this affects system configurations that do not use and ARM interconnect
553   IP. This needs to be enabled for revisions r0p0 and r0p1. It has been fixed
554   in r0p2.
555
556-  ``ERRATA_V2_2719105``: This applies errata 2719105 workaround to Neoverse-V2
557   CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in
558   r0p2.
559
560-  ``ERRATA_V2_2743011``: This applies errata 2743011 workaround to Neoverse-V2
561   CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in
562   r0p2.
563
564-  ``ERRATA_V2_2779510``: This applies errata 2779510 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_2801372``: This applies errata 2801372 workaround to Neoverse-V2
569   CPU, this affects all configurations. This needs to be enabled for revisions
570   r0p0 and r0p1. It has been fixed in r0p2.
571
572-  ``ERRATA_V2_3701771``: This applies errata 3701771 workaround to Neoverse-V2
573   CPU. This needs to be enabled for revisions r0p0, r0p1 and r0p2 and is
574   still open.
575
576-  ``ERRATA_V2_3841324``: This applies errata 3841324 workaround to Neoverse-V2
577   CPU. This needs to be enabled only for revisions r0p0 and r0p1 of
578   the CPU. It is fixed in r0p2.
579
580For Neoverse V3, the following errata build flags are defined :
581
582- ``ERRATA_V3_2970647``: This applies errata 2970647 workaround to Neoverse-V3
583  CPU. This needs to be enabled for revision r0p0. It is fixed in r0p1.
584
585- ``ERRATA_V3_3701767``: This applies errata 3701767 workaround to Neoverse-V3
586  CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2 of the CPU and
587  is still open.
588
589For Cortex-A710, the following errata build flags are defined :
590
591-  ``ERRATA_A710_1901946``: This applies errata 1901946 workaround to
592   Cortex-A710 CPU. This needs to be enabled only for revision r1p0. It has
593   been fixed in r2p0.
594
595-  ``ERRATA_A710_1916945``: This applies errata 1916945 workaround to
596   Cortex-A710 CPU. This needs to be enabled only for revisions r0p0 and r1p0.
597   It has been fixed in r2p0.
598
599-  ``ERRATA_A710_1917258``: This applies errata 1917258 workaround to
600   Cortex-A710 CPU. This needs to be enabled only for revisions r0p0 and r1p0.
601   It has been fixed in r2p0.
602
603-  ``ERRATA_A710_1927200``: This applies errata 1927200 workaround to
604   Cortex-A710 CPU. This needs to be enabled only for revisions r0p0 and r1p0.
605   It has been fixed in r2p0.
606
607-  ``ERRATA_A710_1987031``: This applies errata 1987031 workaround to
608   Cortex-A710 CPU. This needs to be enabled only for revisions r0p0, r1p0 and
609   r2p0 of the CPU. It is still open.
610
611-  ``ERRATA_A710_2081180``: This applies errata 2081180 workaround to
612   Cortex-A710 CPU. This needs to be enabled only for revisions r0p0, r1p0 and
613   r2p0 of the CPU. It is still open.
614
615-  ``ERRATA_A710_2055002``: This applies errata 2055002 workaround to
616   Cortex-A710 CPU. This needs to be enabled for revisions r1p0, r2p0 of the CPU
617   and is still open.
618
619-  ``ERRATA_A710_2017096``: This applies errata 2017096 workaround to
620   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
621   of the CPU and is still open.
622
623-  ``ERRATA_A710_2083908``: This applies errata 2083908 workaround to
624   Cortex-A710 CPU. This needs to be enabled for revision r2p0 of the CPU and
625   is still open.
626
627-  ``ERRATA_A710_2267065``: This applies errata 2267065 workaround to
628   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
629   of the CPU and is fixed in r2p1.
630
631-  ``ERRATA_A710_2136059``: This applies errata 2136059 workaround to
632   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
633   of the CPU and is fixed in r2p1.
634
635-  ``ERRATA_A710_2147715``: This applies errata 2147715 workaround to
636   Cortex-A710 CPU. This needs to be enabled for revision r2p0 of the CPU
637   and is fixed in r2p1.
638
639-  ``ERRATA_A710_2216384``: This applies errata 2216384 workaround to
640   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
641   of the CPU and is fixed in r2p1.
642
643-  ``ERRATA_A710_2282622``: This applies errata 2282622 workaround to
644   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and
645   r2p1 of the CPU and is still open.
646
647- ``ERRATA_A710_2291219``: This applies errata 2291219 workaround to
648   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
649   of the CPU and is fixed in r2p1.
650
651-  ``ERRATA_A710_2008768``: This applies errata 2008768 workaround to
652   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
653   of the CPU and is fixed in r2p1.
654
655-  ``ERRATA_A710_2371105``: This applies errata 2371105 workaround to
656   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
657   of the CPU and is fixed in r2p1.
658
659-  ``ERRATA_A710_2701952``: This applies erratum 2701952 workaround to Cortex-A710
660   CPU, and applies to system configurations that do not use and ARM
661   interconnect IP. This needs to be enabled for r0p0, r1p0, r2p0 and r2p1 and
662   is still open.
663
664-  ``ERRATA_A710_2742423``: This applies errata 2742423 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_2768515``: This applies errata 2768515 workaround to
669   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and
670   r2p1 of the CPU and is still open.
671
672-  ``ERRATA_A710_2778471``: This applies errata 2778471 workaround to Cortex-A710
673   CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and r2p1 of the
674   CPU and is still open.
675
676- ``ERRATA_A710_3701772``: This applies errata 3701772 workaround to Cortex-A710
677  CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0, r2p1 of the
678  CPU and is still open.
679
680For Neoverse N2, the following errata build flags are defined :
681
682-  ``ERRATA_N2_2002655``: This applies errata 2002655 workaround to Neoverse-N2
683   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
684
685-  ``ERRATA_N2_2009478``: This applies errata 2009478 workaround to Neoverse-N2
686   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
687
688-  ``ERRATA_N2_2067956``: This applies errata 2067956 workaround to Neoverse-N2
689   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
690
691-  ``ERRATA_N2_2025414``: This applies errata 2025414 workaround to Neoverse-N2
692   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
693
694-  ``ERRATA_N2_2189731``: This applies errata 2189731 workaround to Neoverse-N2
695   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
696
697-  ``ERRATA_N2_2138956``: This applies errata 2138956 workaround to Neoverse-N2
698   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
699
700-  ``ERRATA_N2_2242415``: This applies errata 2242415 workaround to Neoverse-N2
701   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
702
703-  ``ERRATA_N2_2138958``: This applies errata 2138958 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_2242400``: This applies errata 2242400 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_2280757``: This applies errata 2280757 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_2326639``: This applies errata 2326639 workaround to Neoverse-N2
713   CPU. This needs to be enabled for revision r0p0 of the CPU, it is fixed in
714   r0p1.
715
716-  ``ERRATA_N2_2340933``: This applies errata 2340933 workaround to Neoverse-N2
717   CPU. This needs to be enabled for revision r0p0 of the CPU, it is fixed in
718   r0p1.
719
720-  ``ERRATA_N2_2346952``: This applies errata 2346952 workaround to Neoverse-N2
721   CPU. This needs to be enabled for revisions r0p0, r0p1 and r0p2 of the CPU,
722   it is fixed in r0p3.
723
724-  ``ERRATA_N2_2376738``: This applies errata 2376738 workaround to Neoverse-N2
725   CPU. This needs to be enabled for revision r0p0, r0p1, r0p2, r0p3 and is still open.
726
727-  ``ERRATA_N2_2388450``: This applies errata 2388450 workaround to Neoverse-N2
728   CPU. This needs to be enabled for revision r0p0 of the CPU, it is fixed in
729   r0p1.
730
731-  ``ERRATA_N2_2743014``: This applies errata 2743014 workaround to Neoverse-N2
732   CPU. This needs to be enabled for revisions r0p0, r0p1 and r0p2. It is fixed
733   in r0p3.
734
735-  ``ERRATA_N2_2743089``: This applies errata 2743089 workaround to Neoverse-N2
736   CPU. This needs to be enabled for revisions r0p0, r0p1 and r0p2. It is fixed
737   in r0p3.
738
739- ``ERRATA_N2_2728475``: This applies erratum 2728475 workaround to Neoverse-N2
740   CPU, this erratum affects system configurations that do not use and ARM
741   interconnect IP. This needs to be enabled for revisions r0p0, r0p1 and r0p2.
742   It is fixed in r0p3.
743
744-  ``ERRATA_N2_2779511``: This applies errata 2779511 workaround to Neoverse-N2
745   CPU. This needs to be enabled for revisions r0p0, r0p1 and r0p2. It is fixed
746   in r0p3.
747
748-  ``ERRATA_N2_3701773``: This applies errata 3701773 workaround to Neoverse-N2
749   CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2, r0p3 and is
750   still open.
751
752For Neoverse N3, the following errata build flags are defined :
753
754-  ``ERRATA_N3_3699563``: This applies errata 3699563 workaround to Neoverse-N3
755   CPU. This needs to be enabled for revisions r0p0 and is still open.
756
757For Cortex-X2, the following errata build flags are defined :
758
759-  ``ERRATA_X2_1901946``: This applies errata 1901946 workaround to Cortex-X2
760   CPU. This needs to be enabled only for r1p0, it is fixed in r2p0.
761
762-  ``ERRATA_X2_1916945``: This applies errata 1916945 workaround to Cortex-X2
763   CPU. This needs to be enabled only for revisions r0p0 and r1p0 of the CPU, it
764   is fixed in r2p0.
765
766-  ``ERRATA_X2_1917258``: This applies errata 1917258 workaround to Cortex-X2
767   CPU. This needs to be enabled only for revisions r0p0 and r1p0 of the CPU, it
768   is fixed in r2p0.
769
770-  ``ERRATA_X2_1927200``: This applies errata 1927200 workaround to Cortex-X2
771   CPU. This needs to be enabled only for revisions r0p0 and r1p0 of the CPU, it
772   is fixed in r2p0.
773
774-  ``ERRATA_X2_1934260``: This applies errata 1934260 workaround to Cortex-X2
775   CPU. This needs to be enabled only for revision r1p0 of the CPU, it is fixed
776   in r2p0.
777
778-  ``ERRATA_X2_2002765``: This applies errata 2002765 workaround to Cortex-X2
779   CPU. This needs to be enabled only for revisions r0p0, r1p0 and r2p0 of the
780   CPU, it is fixed in r2p1.
781
782-  ``ERRATA_X2_2017096``: This applies errata 2017096 workaround to Cortex-X2
783   CPU. This needs to be enabled only for revisions r0p0, r1p0 and r2p0 of the
784   CPU, it is fixed in r2p1.
785
786-  ``ERRATA_X2_2081180``: This applies errata 2081180 workaround to Cortex-X2
787   CPU. This needs to be enabled only for revisions r0p0, r1p0 and r2p0 of the
788   CPU, it is fixed in r2p1.
789
790-  ``ERRATA_X2_2083908``: This applies errata 2083908 workaround to Cortex-X2
791   CPU. This needs to be enabled only for revision r2p0 of the CPU, it is fixed
792   in r2p1.
793
794-  ``ERRATA_X2_2136059``: This applies errata 2136059 workaround to Cortex-X2
795   CPU. This needs to be enabled only for revisions r0p0, r1p0 and r2p0 of the
796   CPU, it is fixed in r2p1.
797
798-  ``ERRATA_X2_2147715``: This applies errata 2147715 workaround to Cortex-X2
799   CPU. This needs to be enabled only for revision r2p0 of the CPU, it is fixed
800   in r2p1.
801
802-  ``ERRATA_X2_2216384``: This applies errata 2216384 workaround to Cortex-X2
803   CPU. This needs to be enabled only for revisions r0p0, r1p0 and r2p0 of the
804   CPU, it is fixed in r2p1.
805
806-  ``ERRATA_X2_2267065``: This applies errata 2267065 workaround to Cortex-X2
807   CPU. This needs to be enabled only for revisions r0p0, r1p0 and r2p0 of the
808   CPU, it is fixed in r2p1.
809
810-  ``ERRATA_X2_2282622``: This applies errata 2282622 workaround to Cortex-X2
811   CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and r2p1 of the
812   CPU and is still open.
813
814-  ``ERRATA_X2_2291219``: This applies errata 2291219 workaround to Cortex-X2
815   CPU. This needs to be enabled only for revisions r0p0, r1p0 and r2p0 of the
816   CPU, it is fixed in r2p1.
817
818-  ``ERRATA_X2_2371105``: This applies errata 2371105 workaround to Cortex-X2
819   CPU. This needs to be enabled only for revisions r0p0, r1p0 and r2p0 of the
820   CPU, it is fixed in r2p1.
821
822- ``ERRATA_X2_2701952``: This applies errata 2701952 workaround to Cortex-X2
823   CPU and affects system configurations that do not use an Arm interconnect IP.
824   This needs to be enabled for revisions r0p0, r1p0, r2p0 and r2p1 and is
825   still open.
826
827-  ``ERRATA_X2_2742423``: This applies errata 2742423 workaround to Cortex-X2
828   CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and r2p1 of the
829   CPU and is still open.
830
831-  ``ERRATA_X2_2768515``: This applies errata 2768515 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_2778471``: This applies errata 2778471 workaround to Cortex-X2
836   CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and r2p1 of the
837   CPU and is still open.
838
839-  ``ERRATA_X2_3701772``: This applies errata 3701772 workaround to Cortex-X2
840   CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and r2p1 of the
841   CPU and is still open.
842
843For Cortex-X3, the following errata build flags are defined :
844
845- ``ERRATA_X3_2266875``: This applies errata 2266875 workaround to the Cortex-X3
846  CPU. This needs to be enabled only for revisions r0p0 and r1p0 of the CPU, it
847  is fixed in r1p1.
848
849- ``ERRATA_X3_2302506``: This applies errata 2302506 workaround to the Cortex-X3
850  CPU. This needs to be enabled only for revisions r0p0, r1p0 and r1p1, it is
851  fixed in r1p2.
852
853- ``ERRATA_X3_2313909``: This applies errata 2313909 workaround to
854  Cortex-X3 CPU. This needs to be enabled only for revisions r0p0 and r1p0
855  of the CPU, it is fixed in r1p1.
856
857- ``ERRATA_X3_2372204``: This applies errata 2372204 workaround to
858  Cortex-X3 CPU. This needs to be enabled only for revisions r0p0 and r1p0
859  of the CPU, it is fixed in r1p1.
860
861- ``ERRATA_X3_2615812``: This applies errata 2615812 workaround to Cortex-X3
862  CPU. This needs to be enabled only for revisions r0p0, r1p0 and r1p1 of the
863  CPU, it is fixed in r1p2.
864
865- ``ERRATA_X3_2641945``: This applies errata 2641945 workaround to Cortex-X3
866  CPU. This needs to be enabled only for revisions r0p0 and r1p0 of the CPU.
867  It is fixed in r1p1.
868
869- ``ERRATA_X3_2701951``: This applies erratum 2701951 workaround to Cortex-X3
870  CPU and affects system configurations that do not use an ARM interconnect
871  IP. This needs to be applied to revisions r0p0, r1p0 and r1p1. It is fixed
872  in r1p2.
873
874- ``ERRATA_X3_2742421``: This applies errata 2742421 workaround to
875  Cortex-X3 CPU. This needs to be enabled only for revisions r0p0, r1p0 and
876  r1p1. It is fixed in r1p2.
877
878- ``ERRATA_X3_2743088``: This applies errata 2743088 workaround to Cortex-X3
879  CPU. This needs to be enabled only for revisions r0p0, r1p0 and r1p1. It is
880  fixed in r1p2.
881
882- ``ERRATA_X3_2779509``: This applies errata 2779509 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_3213672``: This applies errata 3213672 workaround to Cortex-X3
887  CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1 and r1p2
888  of the CPU. It is still open.
889
890- ``ERRATA_X3_3692984``: This applies errata 3692984 workaround to Cortex-X3
891  CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1 and r1p2
892  of the CPU. It is still open.
893
894- ``ERRATA_X3_3701769``: This applies errata 3701769 workaround to Cortex-X3
895  CPU. This needs to be enabled only for revisions r0p0, r1p0, r1p1 and r1p2
896  of the CPU and it is still open.
897
898- ``ERRATA_X3_3827463``: This applies errata 3827463 workaround to Cortex-X3
899  CPU. This needs to be enabled only for revisions r0p0, r1p0 and r1p1 of
900  the CPU. It is fixed in r1p2.
901
902For Cortex-X4, the following errata build flags are defined :
903
904- ``ERRATA_X4_2701112``: This applies erratum 2701112 workaround to Cortex-X4
905  CPU and affects system configurations that do not use an Arm interconnect IP.
906  This needs to be enabled for revisions r0p0 and is fixed in r0p1.
907  The workaround for this erratum is not implemented in EL3, but the flag can
908  be enabled/disabled at the platform level. The flag is used when the errata ABI
909  feature is enabled and can assist the Kernel in the process of
910  mitigation of the erratum.
911
912- ``ERRATA_X4_2726228``: This applies erratum 2726228 workaround to Cortex-X4
913  CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in
914  r0p2.
915
916-  ``ERRATA_X4_2740089``: This applies errata 2740089 workaround to Cortex-X4
917   CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed
918   in r0p2.
919
920- ``ERRATA_X4_2763018``: This applies errata 2763018 workaround to Cortex-X4
921  CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in r0p2.
922
923- ``ERRATA_X4_2816013``: This applies errata 2816013 workaround to Cortex-X4
924  CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in r0p2.
925
926- ``ERRATA_X4_2897503``: This applies errata 2897503 workaround to Cortex-X4
927  CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in r0p2.
928
929- ``ERRATA_X4_2923985``: This applies errata 2923985 workaround to Cortex-X4
930  CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in r0p2.
931
932- ``ERRATA_X4_2957258``: This applies errata 2957258 workaround to Cortex-X4
933  CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in r0p2.
934
935- ``ERRATA_X4_3076789``: This applies errata 3076789 workaround to Cortex-X4
936  CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in r0p2.
937
938- ``ERRATA_X4_3133195``: This applies errata 3133195 workaround to Cortex-X4
939  CPU. This needs to be enabled for revision r0p2. It is fixed in r0p3.
940
941- ``ERRATA_X4_3701758``: This applies errata 3701758 workaround to Cortex-X4
942  CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2 and r0p3.
943  It is still open.
944
945- ``ERRATA_X4_3887999``: This applies errata 3887999 workaround to Cortex-X4
946  CPU. This needs to be enabled for revision r0p0, r0p1, r0p2 and r0p3.
947  It is still open.
948
949For Cortex-X925, the following errata build flags are defined :
950
951- ``ERRATA_X925_2963999``: This applies errata 2963999 workaround to Cortex-X925
952  CPU. This needs to be enabled for revision r0p0. It is fixed in r0p1.
953
954- ``ERRATA_X925_3701747``: This applies errata 3701747 workaround to Cortex-X925
955  CPU. This needs to be enabled for revisions r0p0 and r0p1. It is still open.
956
957For Cortex-A510, the following errata build flags are defined :
958
959-  ``ERRATA_A510_2008766``: This applies errata 2008766 workaround to
960   Cortex-A510 CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2,
961   r0p3, r1p0, r1p1, r1p2 and r1p3. It is still open.
962
963-  ``ERRATA_A510_2288014``: This applies errata 2288014 workaround to
964   Cortex-A510 CPU. This needs to be enabled only for revisions r0p0, r0p1,
965   r0p2, r0p3 and r1p0, it is fixed in r1p1.
966
967-  ``ERRATA_A510_2042739``: This applies errata 2042739 workaround to
968   Cortex-A510 CPU. This needs to be enabled only for revisions r0p0, r0p1 and
969   r0p2, it is fixed in r0p3.
970
971-  ``ERRATA_A510_2041909``: This applies errata 2041909 workaround to
972   Cortex-A510 CPU. This needs to be enabled only for revision r0p2 and is fixed
973   in r0p3. The issue is also present in r0p0 and r0p1 but there is no
974   workaround for those revisions.
975
976-  ``ERRATA_A510_2080326``: This applies errata 2080326 workaround to
977   Cortex-A510 CPU. This needs to be enabled only for revision r0p2 and is
978   fixed in r0p3. This issue is also present in r0p0 and r0p1 but there is no
979   workaround for those revisions.
980
981-  ``ERRATA_A510_2169012``: This applies errata 2169012 workaround to
982   Cortex-A510 CPU. This needs to be enabled only for revisions r0p0, r0p1,
983   r0p2, r0p3 and r1p0, it is fixed in r1p1.
984
985-  ``ERRATA_A510_2218134``: This applies errata 2218134 workaround to
986   Cortex-A510 CPU. This needs to be enabled only for revision r1p0 and is fixed
987   in r1p1.
988
989-  ``ERRATA_A510_2250311``: This applies errata 2250311 workaround to
990   Cortex-A510 CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2,
991   r0p3 and r1p0, it is fixed in r1p1. This workaround disables MPMM even if
992   ENABLE_MPMM=1.
993
994-  ``ERRATA_A510_2218950``: This applies errata 2218950 workaround to
995   Cortex-A510 CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2,
996   r0p3 and r1p0, it is fixed in r1p1.
997
998-  ``ERRATA_A510_2172148``: This applies errata 2172148 workaround to
999   Cortex-A510 CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2,
1000   r0p3 and r1p0, it is fixed in r1p1.
1001
1002-  ``ERRATA_A510_2347730``: This applies errata 2347730 workaround to
1003   Cortex-A510 CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2,
1004   r0p3, r1p0 and r1p1. It is fixed in r1p2.
1005
1006-  ``ERRATA_A510_2371937``: This applies errata 2371937 workaround to
1007   Cortex-A510 CPU. This needs to applied for revisions r0p0, r0p1, r0p2,
1008   r0p3, r1p0, r1p1, and is fixed in r1p2.
1009
1010-  ``ERRATA_A510_2420992``: This applies errata 2420992 workaround to
1011   Cortex-A510 CPU. This needs to applied for revisions r1p0 and r1p1, and is
1012   fixed in r1p2.
1013
1014-  ``ERRATA_A510_2666669``: This applies errata 2666669 workaround to
1015   Cortex-A510 CPU. This needs to applied for revisions r0p0, r0p1, r0p2,
1016   r0p3, r1p0, r1p1. It is fixed in r1p2.
1017
1018-  ``ERRATA_A510_2684597``: This applies erratum 2684597 workaround to
1019   Cortex-A510 CPU. This needs to be applied to revision r0p0, r0p1, r0p2,
1020   r0p3, r1p0, r1p1 and r1p2. It is fixed in r1p3.
1021
1022-  ``ERRATA_A510_2971420``: This applies erratum 2971420 workaround to
1023   Cortex-A510 CPU. This needs to be applied to revisions r0p1, r0p2, r0p3,
1024   r1p0, r1p1, r1p2 and r1p3 and is still open.
1025
1026-  ``ERRATA_A510_3672349``: This applies erratum 3672349 workaround to
1027   Cortex-A510 CPU. This needs to be applied to revisions r0p1, r0p2, r0p3,
1028   r1p0, r1p1, r1p2 and r1p3 and is still open.
1029
1030-  ``ERRATA_A510_3704847``: This applies erratum 3704847 workaround to
1031   Cortex-A510 CPU. This needs to be applied to revisions r0p1, r0p2, r0p3,
1032   r1p0, r1p1, r1p2 and r1p3 and is still open.
1033
1034For Cortex-A520, the following errata build flags are defined :
1035
1036-  ``ERRATA_A520_2630792``: This applies errata 2630792 workaround to
1037   Cortex-A520 CPU. This needs to applied for revisions r0p0, r0p1 of the
1038   CPU and is still open.
1039
1040-  ``ERRATA_A520_2858100``: This applies errata 2858100 workaround to
1041   Cortex-A520 CPU. This needs to be enabled for revisions r0p0 and r0p1.
1042   It is still open.
1043
1044-  ``ERRATA_A520_2938996``: This applies errata 2938996 workaround to
1045   Cortex-A520 CPU. This needs to be enabled for revisions r0p0 and r0p1.
1046   It is fixed in r0p2.
1047
1048For Cortex-A715, the following errata build flags are defined :
1049
1050-  ``ERRATA_A715_2331818``: This applies errata 2331818 workaround to
1051   Cortex-A715 CPU. This needs to be enabled for revisions r0p0 and r1p0.
1052   It is fixed in r1p1.
1053
1054- ``ERRATA_A715_2344187``: This applies errata 2344187 workaround to
1055   Cortex-A715 CPU. This needs to be enabled for revisions r0p0 and r1p0. It is
1056   fixed in r1p1.
1057
1058-  ``ERRATA_A715_2376701``: This applies errata 2376701 workaround to
1059   Cortex-A715 CPU. This needs to be enabled for revisions r0p0 and r1p0. It is
1060   fixed in r1p1.
1061
1062-  ``ERRATA_A715_2409570``: This applies errata 2409570 workaround to
1063   Cortex-A715 CPU. This needs to be enabled only for revision r1p0.
1064   It is fixed in r1p1. This errata also applies to r0p0 but that revision has a
1065   different workaround, and since r0p0 is not used in production hardware it is
1066   not implemented.
1067
1068-  ``ERRATA_A715_2413290``: This applies errata 2413290 workaround to
1069   Cortex-A715 CPU. This needs to be enabled only for revision r1p0 and
1070   when SPE(Statistical profiling extension)=True. The errata is fixed
1071   in r1p1.
1072
1073-  ``ERRATA_A715_2420947``: This applies errata 2420947 workaround to
1074   Cortex-A715 CPU. This needs to be enabled only for revision r1p0.
1075   It is fixed in r1p1.
1076
1077-  ``ERRATA_A715_2429384``: This applies errata 2429384 workaround to
1078   Cortex-A715 CPU. This needs to be enabled for revision r1p0. There is no
1079   workaround for revision r0p0. It is fixed in r1p1.
1080
1081-  ``ERRATA_A715_2561034``: This applies errata 2561034 workaround to
1082   Cortex-A715 CPU. This needs to be enabled only for revision r1p0.
1083   It is fixed in r1p1.
1084
1085-  ``ERRATA_A715_2728106``: This applies errata 2728106 workaround to
1086   Cortex-A715 CPU. This needs to be enabled for revisions r0p0, r1p0
1087   and r1p1. It is fixed in r1p2.
1088
1089-  ``ERRATA_A715_2804830``: This applies errata 2804830 workaround to
1090   Cortex-A715 CPU. This needs to be enabled for revisions r0p0, r1p0,
1091   r1p1 and r1p2. It is fixed in r1p3.
1092
1093-  ``ERRATA_A715_3699560``: This applies errata 3699560 workaround to
1094   Cortex-A715 CPU. This needs to be enabled for revisions r0p0, r1p0,
1095   r1p2 and r1p3. It is still open.
1096
1097-  ``ERRATA_A715_3711916``: This applies errata 3711916 workaround to
1098   Cortex-A715 CPU. This needs to be enabled for revisions r0p0, r1p0,
1099   r1p1, r1p2 and r1p3. It is still open.
1100
1101For Cortex-A720, the following errata build flags are defined :
1102
1103-  ``ERRATA_A720_2729604``: This applies errata 2729604 workaround to
1104   Cortex-A720 CPU. This needs to be enabled for revisions r0p0 and r0p1.
1105   It is fixed in r0p2.
1106
1107-  ``ERRATA_A720_2792132``: This applies errata 2792132 workaround to
1108   Cortex-A720 CPU. This needs to be enabled for revisions r0p0 and r0p1.
1109   It is fixed in r0p2.
1110
1111-  ``ERRATA_A720_2844092``: This applies errata 2844092 workaround to
1112   Cortex-A720 CPU. This needs to be enabled for revisions r0p0 and r0p1.
1113   It is fixed in r0p2.
1114
1115-  ``ERRATA_A720_2926083``: This applies errata 2926083 workaround to
1116   Cortex-A720 CPU. This needs to be enabled for revisions r0p0 and r0p1.
1117   It is fixed in r0p2.
1118
1119-  ``ERRATA_A720_2940794``: This applies errata 2940794 workaround to
1120   Cortex-A720 CPU. This needs to be enabled for revisions r0p0 and r0p1.
1121   It is fixed in r0p2.
1122
1123-  ``ERRATA_A720_3699561``: This applies errata 3699561 workaround to
1124   Cortex-A720 CPU. This needs to be enabled for revisions r0p0, r0p1
1125   and r0p2. It is still open.
1126
1127-  ``ERRATA_A720_3711910``: This applies errata 3711910 workaround to
1128   Cortex-A720 CPU. This needs to be enabled for revisions r0p0, r0p1
1129   and r0p2. It is still open.
1130
1131For Cortex-A720_AE, the following errata build flags are defined :
1132
1133-  ``ERRATA_A720_AE_3699562``: This applies errata 3699562 workaround
1134   to Cortex-A720_AE CPU. This needs to be enabled for revisions r0p0.
1135   It is still open.
1136
1137For Cortex-A725, the following errata build flags are defined :
1138
1139-  ``ERRATA_A725_3699564``: This applies errata 3699564 workaround to
1140   Cortex-A725 CPU. This needs to be enabled for revisions r0p0 and r0p1.
1141   It is fixed in r0p2.
1142
1143DSU Errata Workarounds
1144----------------------
1145
1146Similar to CPU errata, TF-A also implements workarounds for DSU (DynamIQ
1147Shared Unit) errata. The DSU errata details can be found in the respective Arm
1148documentation:
1149
1150- `Arm DSU Software Developers Errata Notice`_.
1151
1152Each erratum is identified by an ``ID``, as defined in the DSU errata notice
1153document. Thus, the build flags which enable/disable the errata workarounds
1154have the format ``ERRATA_DSU_<ID>``. The implementation and application logic
1155of DSU errata workarounds are similar to `CPU errata workarounds`_.
1156
1157For DSU errata, the following build flags are defined:
1158
1159-  ``ERRATA_DSU_798953``: This applies errata 798953 workaround for the
1160   affected DSU configurations. This errata applies only for those DSUs that
1161   revision is r0p0 (on r0p1 it is fixed). However, please note that this
1162   workaround results in increased DSU power consumption on idle.
1163
1164-  ``ERRATA_DSU_936184``: This applies errata 936184 workaround for the
1165   affected DSU configurations. This errata applies only for those DSUs that
1166   contain the ACP interface **and** the DSU revision is older than r2p0 (on
1167   r2p0 it is fixed). However, please note that this workaround results in
1168   increased DSU power consumption on idle.
1169
1170-  ``ERRATA_DSU_2313941``: This applies errata 2313941 workaround for the
1171   affected DSU configurations. This errata applies for those DSUs with
1172   revisions r0p0, r1p0, r2p0, r2p1, r3p0, r3p1 and is still open. However,
1173   please note that this workaround results in increased DSU power consumption
1174   on idle.
1175
1176-  ``ERRATA_DSU_2900952``: This applies errata 2900952 workaround for the
1177   affected DSU-120 configurations. This erratum applies to some r2p0
1178   implementations and is fixed in r2p1. The affected r2p0 implementations
1179   are determined by reading the IMP_CLUSTERREVIDR_EL1[1] register bit
1180   and making sure it's clear.
1181
1182CPU Specific optimizations
1183--------------------------
1184
1185This section describes some of the optimizations allowed by the CPU micro
1186architecture that can be enabled by the platform as desired.
1187
1188-  ``SKIP_A57_L1_FLUSH_PWR_DWN``: This flag enables an optimization in the
1189   Cortex-A57 cluster power down sequence by not flushing the Level 1 data
1190   cache. The L1 data cache and the L2 unified cache are inclusive. A flush
1191   of the L2 by set/way flushes any dirty lines from the L1 as well. This
1192   is a known safe deviation from the Cortex-A57 TRM defined power down
1193   sequence. Each Cortex-A57 based platform must make its own decision on
1194   whether to use the optimization.
1195
1196-  ``A53_DISABLE_NON_TEMPORAL_HINT``: This flag disables the cache non-temporal
1197   hint. The LDNP/STNP instructions as implemented on Cortex-A53 do not behave
1198   in a way most programmers expect, and will most probably result in a
1199   significant speed degradation to any code that employs them. The Armv8-A
1200   architecture (see Arm DDI 0487A.h, section D3.4.3) allows cores to ignore
1201   the non-temporal hint and treat LDNP/STNP as LDP/STP instead. Enabling this
1202   flag enforces this behaviour. This needs to be enabled only for revisions
1203   <= r0p3 of the CPU and is enabled by default.
1204
1205-  ``A57_DISABLE_NON_TEMPORAL_HINT``: This flag has the same behaviour as
1206   ``A53_DISABLE_NON_TEMPORAL_HINT`` but for Cortex-A57. This needs to be
1207   enabled only for revisions <= r1p2 of the CPU and is enabled by default,
1208   as recommended in section "4.7 Non-Temporal Loads/Stores" of the
1209   `Cortex-A57 Software Optimization Guide`_.
1210
1211- ''A57_ENABLE_NON_CACHEABLE_LOAD_FWD'': This flag enables non-cacheable
1212   streaming enhancement feature for Cortex-A57 CPUs. Platforms can set
1213   this bit only if their memory system meets the requirement that cache
1214   line fill requests from the Cortex-A57 processor are atomic. Each
1215   Cortex-A57 based platform must make its own decision on whether to use
1216   the optimization. This flag is disabled by default.
1217
1218-  ``NEOVERSE_Nx_EXTERNAL_LLC``: This flag indicates that an external last
1219   level cache(LLC) is present in the system, and that the DataSource field
1220   on the master CHI interface indicates when data is returned from the LLC.
1221   This is used to control how the LL_CACHE* PMU events count.
1222   Default value is 0 (Disabled).
1223
1224-  ``NEOVERSE_N2_PREFETCHER_DISABLE``: This flag disables the region prefetcher
1225   on the Neoverse N2 core. This is used during performance analysis to get clean
1226   and repeatable measurements of the cache by preventing speculative data fetches
1227   from interfering with benchmark results.
1228   Default value is 0 (Disabled).
1229
1230GIC Errata Workarounds
1231----------------------
1232-  ``GIC600_ERRATA_WA_2384374``: This flag applies part 2 of errata 2384374
1233   workaround for the affected GIC600 and GIC600-AE implementations. It applies
1234   to implementations of GIC600 and GIC600-AE with revisions less than or equal
1235   to r1p6 and r0p2 respectively. If the platform sets GICV3_SUPPORT_GIC600,
1236   then this flag is enabled; otherwise, it is 0 (Disabled).
1237
1238--------------
1239
1240*Copyright (c) 2014-2025, Arm Limited and Contributors. All rights reserved.*
1241
1242.. _CVE-2017-5715: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-5715
1243.. _CVE-2018-3639: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-3639
1244.. _CVE-2022-23960: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-23960
1245.. _Cortex-A72 MPCore Software Developers Errata Notice: https://developer.arm.com/documentation/epm012079/latest
1246.. _Cortex-A57 Software Optimization Guide: https://developer.arm.com/documentation/uan0015
1247.. _Arm DSU Software Developers Errata Notice: https://developer.arm.com/documentation/SDEN854652
1248