xref: /rk3399_ARM-atf/docs/design/cpu-specific-build-macros.rst (revision 323f9ee4ebaa1af23daafc4fad0b04498862a0e1)
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_3696307``: This applies errata 3696307 workaround to Neoverse-V3
607  CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in
608  r0p2.
609
610- ``ERRATA_V3_3701767``: This applies errata 3701767 workaround to Neoverse-V3
611  CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2 of the CPU and
612  is still open.
613
614- ``ERRATA_V3_3734562``: This applies errata 3734562 workaround to Neoverse-V3
615  CPU. This needs to be enabled for revisions r0p0 and r0p1 of the CPU and
616  is fixed in r0p2.
617
618- ``ERRATA_V3_3782181``: This applies errata 3782181 workaround to Neoverse-V3
619  CPU. This needs to be enabled for revision r0p1 of the CPU and is fixed in
620  r0p2.
621
622- ``ERRATA_V3_3864536``: This applies errata 3864536 workaround to Neoverse-V3
623  CPU. This needs to be enabled for revisions r0p0, r0p1 and r0p2 of the CPU and
624  is still open.
625
626For Cortex-A710, the following errata build flags are defined :
627
628-  ``ERRATA_A710_1901946``: This applies errata 1901946 workaround to
629   Cortex-A710 CPU. This needs to be enabled only for revision r1p0. It has
630   been fixed in r2p0.
631
632-  ``ERRATA_A710_1916945``: This applies errata 1916945 workaround to
633   Cortex-A710 CPU. This needs to be enabled only for revisions r0p0 and r1p0.
634   It has been fixed in r2p0.
635
636-  ``ERRATA_A710_1917258``: This applies errata 1917258 workaround to
637   Cortex-A710 CPU. This needs to be enabled only for revisions r0p0 and r1p0.
638   It has been fixed in r2p0.
639
640-  ``ERRATA_A710_1927200``: This applies errata 1927200 workaround to
641   Cortex-A710 CPU. This needs to be enabled only for revisions r0p0 and r1p0.
642   It has been fixed in r2p0.
643
644-  ``ERRATA_A710_1987031``: This applies errata 1987031 workaround to
645   Cortex-A710 CPU. This needs to be enabled only for revisions r0p0, r1p0 and
646   r2p0 of the CPU. It is still open.
647
648-  ``ERRATA_A710_2081180``: This applies errata 2081180 workaround to
649   Cortex-A710 CPU. This needs to be enabled only for revisions r0p0, r1p0 and
650   r2p0 of the CPU. It is still open.
651
652-  ``ERRATA_A710_2055002``: This applies errata 2055002 workaround to
653   Cortex-A710 CPU. This needs to be enabled for revisions r1p0, r2p0 of the CPU
654   and is still open.
655
656-  ``ERRATA_A710_2017096``: This applies errata 2017096 workaround to
657   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
658   of the CPU and is still open.
659
660-  ``ERRATA_A710_2083908``: This applies errata 2083908 workaround to
661   Cortex-A710 CPU. This needs to be enabled for revision r2p0 of the CPU and
662   is still open.
663
664-  ``ERRATA_A710_2267065``: This applies errata 2267065 workaround to
665   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
666   of the CPU and is fixed in r2p1.
667
668-  ``ERRATA_A710_2136059``: This applies errata 2136059 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_2147715``: This applies errata 2147715 workaround to
673   Cortex-A710 CPU. This needs to be enabled for revision r2p0 of the CPU
674   and is fixed in r2p1.
675
676-  ``ERRATA_A710_2216384``: This applies errata 2216384 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_2282622``: This applies errata 2282622 workaround to
681   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and
682   r2p1 of the CPU and is still open.
683
684- ``ERRATA_A710_2291219``: This applies errata 2291219 workaround to
685   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
686   of the CPU and is fixed in r2p1.
687
688-  ``ERRATA_A710_2008768``: This applies errata 2008768 workaround to
689   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
690   of the CPU and is fixed in r2p1.
691
692-  ``ERRATA_A710_2371105``: This applies errata 2371105 workaround to
693   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
694   of the CPU and is fixed in r2p1.
695
696-  ``ERRATA_A710_2701952``: This applies erratum 2701952 workaround to Cortex-A710
697   CPU, and applies to system configurations that do not use and ARM
698   interconnect IP. This needs to be enabled for r0p0, r1p0, r2p0 and r2p1 and
699   is still open.
700
701-  ``ERRATA_A710_2742423``: This applies errata 2742423 workaround to
702   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and
703   r2p1 of the CPU and is still open.
704
705-  ``ERRATA_A710_2768515``: This applies errata 2768515 workaround to
706   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and
707   r2p1 of the CPU and is still open.
708
709-  ``ERRATA_A710_2778471``: This applies errata 2778471 workaround to Cortex-A710
710   CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and r2p1 of the
711   CPU and is still open.
712
713-  ``ERRATA_A710_3324338``: This applies errata 3324338 workaround to
714   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and
715   r2p1 of the CPU and is still open.
716
717- ``ERRATA_A710_3701772``: This applies errata 3701772 workaround to Cortex-A710
718  CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0, r2p1 of the
719  CPU and is still open.
720
721For Neoverse N2, the following errata build flags are defined :
722
723-  ``ERRATA_N2_2002655``: This applies errata 2002655 workaround to Neoverse-N2
724   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
725
726-  ``ERRATA_N2_2009478``: This applies errata 2009478 workaround to Neoverse-N2
727   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
728
729-  ``ERRATA_N2_2067956``: This applies errata 2067956 workaround to Neoverse-N2
730   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
731
732-  ``ERRATA_N2_2025414``: This applies errata 2025414 workaround to Neoverse-N2
733   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
734
735-  ``ERRATA_N2_2189731``: This applies errata 2189731 workaround to Neoverse-N2
736   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
737
738-  ``ERRATA_N2_2138956``: This applies errata 2138956 workaround to Neoverse-N2
739   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
740
741-  ``ERRATA_N2_2242415``: This applies errata 2242415 workaround to Neoverse-N2
742   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
743
744-  ``ERRATA_N2_2138958``: This applies errata 2138958 workaround to Neoverse-N2
745   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
746
747-  ``ERRATA_N2_2242400``: This applies errata 2242400 workaround to Neoverse-N2
748   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
749
750-  ``ERRATA_N2_2280757``: This applies errata 2280757 workaround to Neoverse-N2
751   CPU. This needs to be enabled for revision r0p0 of the CPU and is fixed in r0p1.
752
753-  ``ERRATA_N2_2326639``: This applies errata 2326639 workaround to Neoverse-N2
754   CPU. This needs to be enabled for revision r0p0 of the CPU, it is fixed in
755   r0p1.
756
757-  ``ERRATA_N2_2340933``: This applies errata 2340933 workaround to Neoverse-N2
758   CPU. This needs to be enabled for revision r0p0 of the CPU, it is fixed in
759   r0p1.
760
761-  ``ERRATA_N2_2346952``: This applies errata 2346952 workaround to Neoverse-N2
762   CPU. This needs to be enabled for revisions r0p0, r0p1 and r0p2 of the CPU,
763   it is fixed in r0p3.
764
765-  ``ERRATA_N2_2376738``: This applies errata 2376738 workaround to Neoverse-N2
766   CPU. This needs to be enabled for revision r0p0, r0p1, r0p2, r0p3 and is still open.
767
768-  ``ERRATA_N2_2388450``: This applies errata 2388450 workaround to Neoverse-N2
769   CPU. This needs to be enabled for revision r0p0 of the CPU, it is fixed in
770   r0p1.
771
772-  ``ERRATA_N2_2743014``: This applies errata 2743014 workaround to Neoverse-N2
773   CPU. This needs to be enabled for revisions r0p0, r0p1 and r0p2. It is fixed
774   in r0p3.
775
776-  ``ERRATA_N2_2743089``: This applies errata 2743089 workaround to Neoverse-N2
777   CPU. This needs to be enabled for revisions r0p0, r0p1 and r0p2. It is fixed
778   in r0p3.
779
780- ``ERRATA_N2_2728475``: This applies erratum 2728475 workaround to Neoverse-N2
781   CPU, this erratum affects system configurations that do not use and ARM
782   interconnect IP. This needs to be enabled for revisions r0p0, r0p1 and r0p2.
783   It is fixed in r0p3.
784
785-  ``ERRATA_N2_2779511``: This applies errata 2779511 workaround to Neoverse-N2
786   CPU. This needs to be enabled for revisions r0p0, r0p1 and r0p2. It is fixed
787   in r0p3.
788
789-  ``ERRATA_N2_3701773``: This applies errata 3701773 workaround to Neoverse-N2
790   CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2, r0p3 and is
791   still open.
792
793For Neoverse N3, the following errata build flags are defined :
794
795-  ``ERRATA_N3_3699563``: This applies errata 3699563 workaround to Neoverse-N3
796   CPU. This needs to be enabled for revisions r0p0 and is still open.
797
798For Cortex-X2, the following errata build flags are defined :
799
800-  ``ERRATA_X2_1901946``: This applies errata 1901946 workaround to Cortex-X2
801   CPU. This needs to be enabled only for r1p0, it is fixed in r2p0.
802
803-  ``ERRATA_X2_1916945``: This applies errata 1916945 workaround to Cortex-X2
804   CPU. This needs to be enabled only for revisions r0p0 and r1p0 of the CPU, it
805   is fixed in r2p0.
806
807-  ``ERRATA_X2_1917258``: This applies errata 1917258 workaround to Cortex-X2
808   CPU. This needs to be enabled only for revisions r0p0 and r1p0 of the CPU, it
809   is fixed in r2p0.
810
811-  ``ERRATA_X2_1927200``: This applies errata 1927200 workaround to Cortex-X2
812   CPU. This needs to be enabled only for revisions r0p0 and r1p0 of the CPU, it
813   is fixed in r2p0.
814
815-  ``ERRATA_X2_1934260``: This applies errata 1934260 workaround to Cortex-X2
816   CPU. This needs to be enabled only for revision r1p0 of the CPU, it is fixed
817   in r2p0.
818
819-  ``ERRATA_X2_2002765``: This applies errata 2002765 workaround to Cortex-X2
820   CPU. This needs to be enabled only for revisions r0p0, r1p0 and r2p0 of the
821   CPU, it is fixed in r2p1.
822
823-  ``ERRATA_X2_2017096``: This applies errata 2017096 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_2081180``: This applies errata 2081180 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_2083908``: This applies errata 2083908 workaround to Cortex-X2
832   CPU. This needs to be enabled only for revision r2p0 of the CPU, it is fixed
833   in r2p1.
834
835-  ``ERRATA_X2_2136059``: This applies errata 2136059 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_2147715``: This applies errata 2147715 workaround to Cortex-X2
840   CPU. This needs to be enabled only for revision r2p0 of the CPU, it is fixed
841   in r2p1.
842
843-  ``ERRATA_X2_2216384``: This applies errata 2216384 workaround to Cortex-X2
844   CPU. This needs to be enabled only for revisions r0p0, r1p0 and r2p0 of the
845   CPU, it is fixed in r2p1.
846
847-  ``ERRATA_X2_2267065``: This applies errata 2267065 workaround to Cortex-X2
848   CPU. This needs to be enabled only for revisions r0p0, r1p0 and r2p0 of the
849   CPU, it is fixed in r2p1.
850
851-  ``ERRATA_X2_2282622``: This applies errata 2282622 workaround to Cortex-X2
852   CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and r2p1 of the
853   CPU and is still open.
854
855-  ``ERRATA_X2_2291219``: This applies errata 2291219 workaround to Cortex-X2
856   CPU. This needs to be enabled only for revisions r0p0, r1p0 and r2p0 of the
857   CPU, it is fixed in r2p1.
858
859-  ``ERRATA_X2_2371105``: This applies errata 2371105 workaround to Cortex-X2
860   CPU. This needs to be enabled only for revisions r0p0, r1p0 and r2p0 of the
861   CPU, it is fixed in r2p1.
862
863- ``ERRATA_X2_2701952``: This applies errata 2701952 workaround to Cortex-X2
864   CPU and affects system configurations that do not use an Arm interconnect IP.
865   This needs to be enabled for revisions r0p0, r1p0, r2p0 and r2p1 and is
866   still open.
867
868-  ``ERRATA_X2_2742423``: This applies errata 2742423 workaround to Cortex-X2
869   CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and r2p1 of the
870   CPU and is still open.
871
872-  ``ERRATA_X2_2768515``: This applies errata 2768515 workaround to Cortex-X2
873   CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and r2p1 of the
874   CPU and is still open.
875
876-  ``ERRATA_X2_2778471``: This applies errata 2778471 workaround to Cortex-X2
877   CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and r2p1 of the
878   CPU and is still open.
879
880-  ``ERRATA_X2_3324338``: This applies errata 3324338 workaround to Cortex-X2
881   CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and r2p1 of the
882   CPU and is still open.
883
884-  ``ERRATA_X2_3701772``: This applies errata 3701772 workaround to Cortex-X2
885   CPU. This needs to be enabled for revisions r0p0, r1p0, r2p0 and r2p1 of the
886   CPU and is still open.
887
888For Cortex-X3, the following errata build flags are defined :
889
890- ``ERRATA_X3_2266875``: This applies errata 2266875 workaround to the Cortex-X3
891  CPU. This needs to be enabled only for revisions r0p0 and r1p0 of the CPU, it
892  is fixed in r1p1.
893
894- ``ERRATA_X3_2302506``: This applies errata 2302506 workaround to the Cortex-X3
895  CPU. This needs to be enabled only for revisions r0p0, r1p0 and r1p1, it is
896  fixed in r1p2.
897
898- ``ERRATA_X3_2313909``: This applies errata 2313909 workaround to
899  Cortex-X3 CPU. This needs to be enabled only for revisions r0p0 and r1p0
900  of the CPU, it is fixed in r1p1.
901
902- ``ERRATA_X3_2372204``: This applies errata 2372204 workaround to
903  Cortex-X3 CPU. This needs to be enabled only for revisions r0p0 and r1p0
904  of the CPU, it is fixed in r1p1.
905
906- ``ERRATA_X3_2615812``: This applies errata 2615812 workaround to Cortex-X3
907  CPU. This needs to be enabled only for revisions r0p0, r1p0 and r1p1 of the
908  CPU, it is fixed in r1p2.
909
910- ``ERRATA_X3_2641945``: This applies errata 2641945 workaround to Cortex-X3
911  CPU. This needs to be enabled only for revisions r0p0 and r1p0 of the CPU.
912  It is fixed in r1p1.
913
914- ``ERRATA_X3_2701951``: This applies erratum 2701951 workaround to Cortex-X3
915  CPU and affects system configurations that do not use an ARM interconnect
916  IP. This needs to be applied to revisions r0p0, r1p0 and r1p1. It is fixed
917  in r1p2.
918
919- ``ERRATA_X3_2742421``: This applies errata 2742421 workaround to
920  Cortex-X3 CPU. This needs to be enabled only for revisions r0p0, r1p0 and
921  r1p1. It is fixed in r1p2.
922
923- ``ERRATA_X3_2743088``: This applies errata 2743088 workaround to Cortex-X3
924  CPU. This needs to be enabled only for revisions r0p0, r1p0 and r1p1. It is
925  fixed in r1p2.
926
927- ``ERRATA_X3_2779509``: This applies errata 2779509 workaround to Cortex-X3
928  CPU. This needs to be enabled only for revisions r0p0, r1p0 and r1p1 of the
929  CPU. It is fixed in r1p2.
930
931- ``ERRATA_X3_3213672``: This applies errata 3213672 workaround to Cortex-X3
932  CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1 and r1p2
933  of the CPU. It is still open.
934
935- ``ERRATA_X3_3692984``: This applies errata 3692984 workaround to Cortex-X3
936  CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1 and r1p2
937  of the CPU. It is still open.
938
939- ``ERRATA_X3_3701769``: This applies errata 3701769 workaround to Cortex-X3
940  CPU. This needs to be enabled only for revisions r0p0, r1p0, r1p1 and r1p2
941  of the CPU and it is still open.
942
943- ``ERRATA_X3_3827463``: This applies errata 3827463 workaround to Cortex-X3
944  CPU. This needs to be enabled only for revisions r0p0, r1p0 and r1p1 of
945  the CPU. It is fixed in r1p2.
946
947For Cortex-X4, the following errata build flags are defined :
948
949- ``ERRATA_X4_2701112``: This applies erratum 2701112 workaround to Cortex-X4
950  CPU and affects system configurations that do not use an Arm interconnect IP.
951  This needs to be enabled for revisions r0p0 and is fixed in r0p1.
952  The workaround for this erratum is not implemented in EL3, but the flag can
953  be enabled/disabled at the platform level. The flag is used when the errata ABI
954  feature is enabled and can assist the Kernel in the process of
955  mitigation of the erratum.
956
957- ``ERRATA_X4_2726228``: This applies erratum 2726228 workaround to Cortex-X4
958  CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in
959  r0p2.
960
961-  ``ERRATA_X4_2740089``: This applies errata 2740089 workaround to Cortex-X4
962   CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed
963   in r0p2.
964
965- ``ERRATA_X4_2763018``: This applies errata 2763018 workaround to Cortex-X4
966  CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in r0p2.
967
968- ``ERRATA_X4_2816013``: This applies errata 2816013 workaround to Cortex-X4
969  CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in r0p2.
970
971- ``ERRATA_X4_2897503``: This applies errata 2897503 workaround to Cortex-X4
972  CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in r0p2.
973
974- ``ERRATA_X4_2923985``: This applies errata 2923985 workaround to Cortex-X4
975  CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in r0p2.
976
977- ``ERRATA_X4_2957258``: This applies errata 2957258 workaround to Cortex-X4
978  CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in r0p2.
979
980- ``ERRATA_X4_3076789``: This applies errata 3076789 workaround to Cortex-X4
981  CPU. This needs to be enabled for revisions r0p0 and r0p1. It is fixed in r0p2.
982
983- ``ERRATA_X4_3133195``: This applies errata 3133195 workaround to Cortex-X4
984  CPU. This needs to be enabled for revision r0p2. It is fixed in r0p3.
985
986- ``ERRATA_X4_3701758``: This applies errata 3701758 workaround to Cortex-X4
987  CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2 and r0p3.
988  It is still open.
989
990- ``ERRATA_X4_3887999``: This applies errata 3887999 workaround to Cortex-X4
991  CPU. This needs to be enabled for revision r0p0, r0p1, r0p2 and r0p3.
992  It is still open.
993
994For Cortex-X925, the following errata build flags are defined :
995
996- ``ERRATA_X925_2963999``: This applies errata 2963999 workaround to Cortex-X925
997  CPU. This needs to be enabled for revision r0p0. It is fixed in r0p1.
998
999- ``ERRATA_X925_3701747``: This applies errata 3701747 workaround to Cortex-X925
1000  CPU. This needs to be enabled for revisions r0p0 and r0p1. It is still open.
1001
1002For Cortex-A510, the following errata build flags are defined :
1003
1004-  ``ERRATA_A510_2008766``: This applies errata 2008766 workaround to
1005   Cortex-A510 CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2,
1006   r0p3, r1p0, r1p1, r1p2 and r1p3. It is still open.
1007
1008-  ``ERRATA_A510_2288014``: This applies errata 2288014 workaround to
1009   Cortex-A510 CPU. This needs to be enabled only for revisions r0p0, r0p1,
1010   r0p2, r0p3 and r1p0, it is fixed in r1p1.
1011
1012-  ``ERRATA_A510_2042739``: This applies errata 2042739 workaround to
1013   Cortex-A510 CPU. This needs to be enabled only for revisions r0p0, r0p1 and
1014   r0p2, it is fixed in r0p3.
1015
1016-  ``ERRATA_A510_2041909``: This applies errata 2041909 workaround to
1017   Cortex-A510 CPU. This needs to be enabled only for revision r0p2 and is fixed
1018   in r0p3. The issue is also present in r0p0 and r0p1 but there is no
1019   workaround for those revisions.
1020
1021-  ``ERRATA_A510_2080326``: This applies errata 2080326 workaround to
1022   Cortex-A510 CPU. This needs to be enabled only for revision r0p2 and is
1023   fixed in r0p3. This issue is also present in r0p0 and r0p1 but there is no
1024   workaround for those revisions.
1025
1026-  ``ERRATA_A510_2169012``: This applies errata 2169012 workaround to
1027   Cortex-A510 CPU. This needs to be enabled only for revisions r0p0, r0p1,
1028   r0p2, r0p3 and r1p0, it is fixed in r1p1.
1029
1030-  ``ERRATA_A510_2218134``: This applies errata 2218134 workaround to
1031   Cortex-A510 CPU. This needs to be enabled only for revision r1p0 and is fixed
1032   in r1p1.
1033
1034-  ``ERRATA_A510_2250311``: This applies errata 2250311 workaround to
1035   Cortex-A510 CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2,
1036   r0p3 and r1p0, it is fixed in r1p1. This workaround disables MPMM even if
1037   ENABLE_MPMM=1.
1038
1039-  ``ERRATA_A510_2218950``: This applies errata 2218950 workaround to
1040   Cortex-A510 CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2,
1041   r0p3 and r1p0, it is fixed in r1p1.
1042
1043-  ``ERRATA_A510_2172148``: This applies errata 2172148 workaround to
1044   Cortex-A510 CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2,
1045   r0p3 and r1p0, it is fixed in r1p1.
1046
1047-  ``ERRATA_A510_2347730``: This applies errata 2347730 workaround to
1048   Cortex-A510 CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2,
1049   r0p3, r1p0 and r1p1. It is fixed in r1p2.
1050
1051-  ``ERRATA_A510_2371937``: This applies errata 2371937 workaround to
1052   Cortex-A510 CPU. This needs to applied for revisions r0p0, r0p1, r0p2,
1053   r0p3, r1p0, r1p1, and is fixed in r1p2.
1054
1055-  ``ERRATA_A510_2420992``: This applies errata 2420992 workaround to
1056   Cortex-A510 CPU. This needs to applied for revisions r1p0 and r1p1, and is
1057   fixed in r1p2.
1058
1059-  ``ERRATA_A510_2666669``: This applies errata 2666669 workaround to
1060   Cortex-A510 CPU. This needs to applied for revisions r0p0, r0p1, r0p2,
1061   r0p3, r1p0, r1p1. It is fixed in r1p2.
1062
1063-  ``ERRATA_A510_2684597``: This applies erratum 2684597 workaround to
1064   Cortex-A510 CPU. This needs to be applied to revision r0p0, r0p1, r0p2,
1065   r0p3, r1p0, r1p1 and r1p2. It is fixed in r1p3.
1066
1067-  ``ERRATA_A510_2971420``: This applies erratum 2971420 workaround to
1068   Cortex-A510 CPU. This needs to be applied to revisions r0p1, r0p2, r0p3,
1069   r1p0, r1p1, r1p2 and r1p3 and is still open.
1070
1071-  ``ERRATA_A510_3672349``: This applies erratum 3672349 workaround to
1072   Cortex-A510 CPU. This needs to be applied to revisions r0p1, r0p2, r0p3,
1073   r1p0, r1p1, r1p2 and r1p3 and is still open.
1074
1075-  ``ERRATA_A510_3704847``: This applies erratum 3704847 workaround to
1076   Cortex-A510 CPU. This needs to be applied to revisions r0p1, r0p2, r0p3,
1077   r1p0, r1p1, r1p2 and r1p3 and is still open.
1078
1079For Cortex-A520, the following errata build flags are defined :
1080
1081-  ``ERRATA_A520_2630792``: This applies errata 2630792 workaround to
1082   Cortex-A520 CPU. This needs to applied for revisions r0p0, r0p1 of the
1083   CPU and is still open.
1084
1085-  ``ERRATA_A520_2858100``: This applies errata 2858100 workaround to
1086   Cortex-A520 CPU. This needs to be enabled for revisions r0p0 and r0p1.
1087   It is still open.
1088
1089-  ``ERRATA_A520_2938996``: This applies errata 2938996 workaround to
1090   Cortex-A520 CPU. This needs to be enabled for revisions r0p0 and r0p1.
1091   It is fixed in r0p2.
1092
1093For Cortex-A715, the following errata build flags are defined :
1094
1095-  ``ERRATA_A715_2331818``: This applies errata 2331818 workaround to
1096   Cortex-A715 CPU. This needs to be enabled for revisions r0p0 and r1p0.
1097   It is fixed in r1p1.
1098
1099- ``ERRATA_A715_2344187``: This applies errata 2344187 workaround to
1100   Cortex-A715 CPU. This needs to be enabled for revisions r0p0 and r1p0. It is
1101   fixed in r1p1.
1102
1103-  ``ERRATA_A715_2376701``: This applies errata 2376701 workaround to
1104   Cortex-A715 CPU. This needs to be enabled for revisions r0p0 and r1p0. It is
1105   fixed in r1p1.
1106
1107-  ``ERRATA_A715_2409570``: This applies errata 2409570 workaround to
1108   Cortex-A715 CPU. This needs to be enabled only for revision r1p0.
1109   It is fixed in r1p1. This errata also applies to r0p0 but that revision has a
1110   different workaround, and since r0p0 is not used in production hardware it is
1111   not implemented.
1112
1113-  ``ERRATA_A715_2413290``: This applies errata 2413290 workaround to
1114   Cortex-A715 CPU. This needs to be enabled only for revision r1p0 and
1115   when SPE(Statistical profiling extension)=True. The errata is fixed
1116   in r1p1.
1117
1118-  ``ERRATA_A715_2420947``: This applies errata 2420947 workaround to
1119   Cortex-A715 CPU. This needs to be enabled only for revision r1p0.
1120   It is fixed in r1p1.
1121
1122-  ``ERRATA_A715_2429384``: This applies errata 2429384 workaround to
1123   Cortex-A715 CPU. This needs to be enabled for revision r1p0. There is no
1124   workaround for revision r0p0. It is fixed in r1p1.
1125
1126-  ``ERRATA_A715_2561034``: This applies errata 2561034 workaround to
1127   Cortex-A715 CPU. This needs to be enabled only for revision r1p0.
1128   It is fixed in r1p1.
1129
1130-  ``ERRATA_A715_2728106``: This applies errata 2728106 workaround to
1131   Cortex-A715 CPU. This needs to be enabled for revisions r0p0, r1p0
1132   and r1p1. It is fixed in r1p2.
1133
1134-  ``ERRATA_A715_2804830``: This applies errata 2804830 workaround to
1135   Cortex-A715 CPU. This needs to be enabled for revisions r0p0, r1p0,
1136   r1p1 and r1p2. It is fixed in r1p3.
1137
1138-  ``ERRATA_A715_3456084``: This applies errata 3456084 workaround to
1139   Cortex-A715 CPU. This needs to be enabled for revisions r0p0, r1p0,
1140   r1p1, r1p2 and r1p3. It is still open.
1141
1142-  ``ERRATA_A715_3699560``: This applies errata 3699560 workaround to
1143   Cortex-A715 CPU. This needs to be enabled for revisions r0p0, r1p0,
1144   r1p2 and r1p3. It is still open.
1145
1146-  ``ERRATA_A715_3711916``: This applies errata 3711916 workaround to
1147   Cortex-A715 CPU. This needs to be enabled for revisions r0p0, r1p0,
1148   r1p1, r1p2 and r1p3. It is still open.
1149
1150For Cortex-A720, the following errata build flags are defined :
1151
1152-  ``ERRATA_A720_2729604``: This applies errata 2729604 workaround to
1153   Cortex-A720 CPU. This needs to be enabled for revisions r0p0 and r0p1.
1154   It is fixed in r0p2.
1155
1156-  ``ERRATA_A720_2792132``: This applies errata 2792132 workaround to
1157   Cortex-A720 CPU. This needs to be enabled for revisions r0p0 and r0p1.
1158   It is fixed in r0p2.
1159
1160-  ``ERRATA_A720_2844092``: This applies errata 2844092 workaround to
1161   Cortex-A720 CPU. This needs to be enabled for revisions r0p0 and r0p1.
1162   It is fixed in r0p2.
1163
1164-  ``ERRATA_A720_2926083``: This applies errata 2926083 workaround to
1165   Cortex-A720 CPU. This needs to be enabled for revisions r0p0 and r0p1.
1166   It is fixed in r0p2.
1167
1168-  ``ERRATA_A720_2940794``: This applies errata 2940794 workaround to
1169   Cortex-A720 CPU. This needs to be enabled for revisions r0p0 and r0p1.
1170   It is fixed in r0p2.
1171
1172-  ``ERRATA_A720_3456091``: This applies errata 3456091 workaround to
1173   Cortex-A720 CPU. This needs to be enabled for revisions r0p0, r0p1
1174   and r0p2. It is still open.
1175
1176-  ``ERRATA_A720_3699561``: This applies errata 3699561 workaround to
1177   Cortex-A720 CPU. This needs to be enabled for revisions r0p0, r0p1
1178   and r0p2. It is still open.
1179
1180-  ``ERRATA_A720_3711910``: This applies errata 3711910 workaround to
1181   Cortex-A720 CPU. This needs to be enabled for revisions r0p0, r0p1
1182   and r0p2. It is still open.
1183
1184For Cortex-A720_AE, the following errata build flags are defined :
1185
1186-  ``ERRATA_A720_AE_3456103``: This applies errata 3456103 workaround to
1187   Cortex-A720_AE CPU. This needs to be enabled for revisions r0p0 and r0p1. It
1188   is still open.
1189
1190-  ``ERRATA_A720_AE_3699562``: This applies errata 3699562 workaround
1191   to Cortex-A720_AE CPU. This needs to be enabled for revisions r0p0.
1192   It is still open.
1193
1194For Cortex-A725, the following errata build flags are defined :
1195
1196-  ``ERRATA_A725_2874943``: This applies errata 2874943 workaround to
1197   Cortex-A725 CPU. This needs to be enabled for revisions r0p0 when
1198   FEAT_SPE is enabled. It is fixed in r0p1.
1199
1200-  ``ERRATA_A725_2936490``: This applies errata 2936490 workaround to
1201   Cortex-A725 CPU. This needs to be enabled for revisions r0p0.
1202   It is fixed in r0p1.
1203
1204-  ``ERRATA_A725_3456106``: This applies errata 3456106 workaround to
1205   Cortex-A725 CPU. This needs to be enabled for revisions r0p0, r0p1
1206   and r0p2. It is still open.
1207
1208-  ``ERRATA_A725_3699564``: This applies errata 3699564 workaround to
1209   Cortex-A725 CPU. This needs to be enabled for revisions r0p0 and r0p1.
1210   It is fixed in r0p2.
1211
1212-  ``ERRATA_A725_3711914``: This applies errata 3711914 workaround to
1213   Cortex-A725 CPU. This needs to be enabled for revisions r0p0 and r0p1.
1214   It is fixed in r0p2.
1215
1216For C1-Ultra, the following errata build flags are defined :
1217
1218-  ``ERRATA_C1ULTRA_3324333``: This applies erratum 3324333 workaround to
1219   C1-Ultra CPU. This needs to be enabled for revision r0p0 and is fixed
1220   in r1p0.
1221
1222-  ``ERRATA_C1ULTRA_3502731``: This applies erratum 3502731 workaround to
1223   C1-Ultra CPU. This needs to be enabled for revision r0p0 and is
1224   fixed in r1p0.
1225
1226-  ``ERRATA_C1ULTRA_3651221``: This applies erratum 3651221 workaround to
1227   C1-Ultra CPU. This needs to be enabled for revision r0p0 and is
1228   fixed in r1p0.
1229
1230-  ``ERRATA_C1ULTRA_3658374``: This applies erratum 3658374 workaround to
1231   C1-Ultra CPU. This needs to be enabled for revisions r0p0 and r1p0 and
1232   is still open.
1233
1234-  ``ERRATA_C1ULTRA_3684152``: This applies erratum 3684152 workaround to
1235   C1-Ultra CPU. This needs to be enabled for revision r0p0 and is
1236   fixed in r1p0.
1237
1238-  ``ERRATA_C1ULTRA_3705939``: This applies erratum 3705939 workaround to
1239   C1-Ultra CPU. This needs to be enabled for revisions r0p0 and r1p0 and
1240   is still open.
1241
1242-  ``ERRATA_C1ULTRA_3815514``: This applies erratum 3815514 workaround to
1243   C1-Ultra CPU. This needs to be enabled for revisions r0p0 and r1p0 and
1244   is still open.
1245
1246-  ``ERRATA_C1ULTRA_3865171``: This applies erratum 3865171 workaround to
1247   C1-Ultra CPU. This needs to be enabled for revisions r0p0 and r1p0 and
1248   is still open.
1249
1250-  ``ERRATA_C1ULTRA_3926381``: This applies erratum 3926381 workaround to
1251   C1-Ultra CPU. This needs to be enabled for revision r1p0 and is still
1252   open.
1253
1254-  ``ERRATA_C1ULTRA_4102704``: This applies erratum 4102704 workaround to
1255   C1-Ultra CPU. This needs to be enabled for revisions r0p0 and r1p0 and
1256   is still open.
1257
1258For C1-Premium, the following errata build flags are defined :
1259
1260-  ``ERRATA_C1PREMIUM_3324333``: This applies errata 3324333 workaround to
1261   C1-Premium CPU. This needs to be enabled for revision r0p0, and is
1262   fixed in r1p0.
1263
1264-  ``ERRATA_C1PREMIUM_3502731``: This applies errata 3502731 workaround to
1265   C1-Premium CPU. This needs to be enabled for revision r0p0, and is fixed
1266   in r1p0.
1267
1268-  ``ERRATA_C1PREMIUM_3651221``: This applies errata 3651221 workaround to
1269   C1-Premium CPU. This needs to be enabled for revision r0p0, and is fixed
1270   in r1p0.
1271
1272-  ``ERRATA_C1PREMIUM_3684152``: This applies errata 3684152 workaround to
1273   C1-Premium CPU. This needs to be enabled for revision r0p0, and is fixed
1274   in r1p0.
1275
1276-  ``ERRATA_C1PREMIUM_3705939``: This applies errata 3705939 workaround to
1277   C1-Premium CPU. This needs to be enabled for revisions r0p0, r1p0 and
1278   is still open.
1279
1280-  ``ERRATA_C1PREMIUM_3815514``: This applies errata 3815514 workaround to
1281   C1-Premium CPU. This needs to be enabled for revisions r0p0, r1p0 and
1282   is still open.
1283
1284-  ``ERRATA_C1PREMIUM_3865171``: This applies errata 3865171 workaround to
1285   C1-Premium CPU. This needs to be enabled for revisions r0p0, r1p0 and
1286   is still open.
1287
1288-  ``ERRATA_C1PREMIUM_3926381``: This applies errata 3926381 workaround to
1289   C1-Premium CPU. This needs to be enabled for revision r1p0 and is
1290   still open.
1291
1292-  ``ERRATA_C1PREMIUM_4102704``: This applies errata 4102704 workaround to
1293   C1-Premium CPU. This needs to be enabled for revisions r0p0, r1p0 and
1294   is still open.
1295
1296DSU Errata Workarounds
1297----------------------
1298
1299Similar to CPU errata, TF-A also implements workarounds for DSU (DynamIQ
1300Shared Unit) errata. The DSU errata details can be found in the respective Arm
1301documentation:
1302
1303- `Arm DSU Software Developers Errata Notice`_.
1304
1305Each erratum is identified by an ``ID``, as defined in the DSU errata notice
1306document. Thus, the build flags which enable/disable the errata workarounds
1307have the format ``ERRATA_DSU_<ID>``. The implementation and application logic
1308of DSU errata workarounds are similar to `CPU errata workarounds`_.
1309
1310For DSU errata, the following build flags are defined:
1311
1312-  ``ERRATA_DSU_798953``: This applies errata 798953 workaround for the
1313   affected DSU configurations. This errata applies only for those DSUs that
1314   revision is r0p0 (on r0p1 it is fixed). However, please note that this
1315   workaround results in increased DSU power consumption on idle.
1316
1317-  ``ERRATA_DSU_936184``: This applies errata 936184 workaround for the
1318   affected DSU configurations. This errata applies only for those DSUs that
1319   contain the ACP interface **and** the DSU revision is older than r2p0 (on
1320   r2p0 it is fixed). However, please note that this workaround results in
1321   increased DSU power consumption on idle.
1322
1323-  ``ERRATA_DSU_2313941``: This applies errata 2313941 workaround for the
1324   affected DSU configurations. This errata applies for those DSUs with
1325   revisions r0p0, r1p0, r2p0, r2p1, r3p0, r3p1 and is still open. However,
1326   please note that this workaround results in increased DSU power consumption
1327   on idle.
1328
1329-  ``ERRATA_DSU_2900952``: This applies errata 2900952 workaround for the
1330   affected DSU-120 configurations. This erratum applies to some r2p0
1331   implementations and is fixed in r2p1. The affected r2p0 implementations
1332   are determined by reading the IMP_CLUSTERREVIDR_EL1[1] register bit
1333   and making sure it's clear.
1334
1335CPU Specific optimizations
1336--------------------------
1337
1338This section describes some of the optimizations allowed by the CPU micro
1339architecture that can be enabled by the platform as desired.
1340
1341-  ``SKIP_A57_L1_FLUSH_PWR_DWN``: This flag enables an optimization in the
1342   Cortex-A57 cluster power down sequence by not flushing the Level 1 data
1343   cache. The L1 data cache and the L2 unified cache are inclusive. A flush
1344   of the L2 by set/way flushes any dirty lines from the L1 as well. This
1345   is a known safe deviation from the Cortex-A57 TRM defined power down
1346   sequence. Each Cortex-A57 based platform must make its own decision on
1347   whether to use the optimization.
1348
1349-  ``A53_DISABLE_NON_TEMPORAL_HINT``: This flag disables the cache non-temporal
1350   hint. The LDNP/STNP instructions as implemented on Cortex-A53 do not behave
1351   in a way most programmers expect, and will most probably result in a
1352   significant speed degradation to any code that employs them. The Armv8-A
1353   architecture (see Arm DDI 0487A.h, section D3.4.3) allows cores to ignore
1354   the non-temporal hint and treat LDNP/STNP as LDP/STP instead. Enabling this
1355   flag enforces this behaviour. This needs to be enabled only for revisions
1356   <= r0p3 of the CPU and is enabled by default.
1357
1358-  ``A57_DISABLE_NON_TEMPORAL_HINT``: This flag has the same behaviour as
1359   ``A53_DISABLE_NON_TEMPORAL_HINT`` but for Cortex-A57. This needs to be
1360   enabled only for revisions <= r1p2 of the CPU and is enabled by default,
1361   as recommended in section "4.7 Non-Temporal Loads/Stores" of the
1362   `Cortex-A57 Software Optimization Guide`_.
1363
1364- ''A57_ENABLE_NON_CACHEABLE_LOAD_FWD'': This flag enables non-cacheable
1365   streaming enhancement feature for Cortex-A57 CPUs. Platforms can set
1366   this bit only if their memory system meets the requirement that cache
1367   line fill requests from the Cortex-A57 processor are atomic. Each
1368   Cortex-A57 based platform must make its own decision on whether to use
1369   the optimization. This flag is disabled by default.
1370
1371-  ``NEOVERSE_Nx_EXTERNAL_LLC``: This flag indicates that an external last
1372   level cache(LLC) is present in the system, and that the DataSource field
1373   on the master CHI interface indicates when data is returned from the LLC.
1374   This is used to control how the LL_CACHE* PMU events count.
1375   Default value is 0 (Disabled).
1376
1377-  ``NEOVERSE_N2_PREFETCHER_DISABLE``: This flag disables the region prefetcher
1378   on the Neoverse N2 core. This is used during performance analysis to get clean
1379   and repeatable measurements of the cache by preventing speculative data fetches
1380   from interfering with benchmark results.
1381   Default value is 0 (Disabled).
1382
1383GIC Errata Workarounds
1384----------------------
1385-  ``GIC600_ERRATA_WA_2384374``: This flag applies part 2 of errata 2384374
1386   workaround for the affected GIC600 and GIC600-AE implementations. It applies
1387   to implementations of GIC600 and GIC600-AE with revisions less than or equal
1388   to r1p6 and r0p2 respectively. If the platform sets GICV3_SUPPORT_GIC600,
1389   then this flag is enabled; otherwise, it is 0 (Disabled).
1390
1391--------------
1392
1393*Copyright (c) 2014-2025, Arm Limited and Contributors. All rights reserved.*
1394
1395.. _CVE-2017-5715: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-5715
1396.. _CVE-2018-3639: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-3639
1397.. _CVE-2022-23960: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-23960
1398.. _CVE-2024-5660: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2024-5660
1399.. _CVE-2024-7881: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2024-7881
1400.. _Cortex-A72 MPCore Software Developers Errata Notice: https://developer.arm.com/documentation/epm012079/latest
1401.. _Cortex-A57 Software Optimization Guide: https://developer.arm.com/documentation/uan0015
1402.. _Arm DSU Software Developers Errata Notice: https://developer.arm.com/documentation/SDEN854652
1403