xref: /rk3399_ARM-atf/docs/design/cpu-specific-build-macros.rst (revision 6dc5979a6cb2121e4c16e7bd62e24030e0f42755)
1Arm CPU Specific Build Macros
2=============================
3
4This document describes the various build options present in the CPU specific
5operations framework to enable errata workarounds and to enable optimizations
6for a specific CPU on a platform.
7
8Security Vulnerability Workarounds
9----------------------------------
10
11TF-A exports a series of build flags which control which security
12vulnerability workarounds should be applied at runtime.
13
14-  ``WORKAROUND_CVE_2017_5715``: Enables the security workaround for
15   `CVE-2017-5715`_. This flag can be set to 0 by the platform if none
16   of the PEs in the system need the workaround. Setting this flag to 0 provides
17   no performance benefit for non-affected platforms, it just helps to comply
18   with the recommendation in the spec regarding workaround discovery.
19   Defaults to 1.
20
21-  ``WORKAROUND_CVE_2018_3639``: Enables the security workaround for
22   `CVE-2018-3639`_. Defaults to 1. The TF-A project recommends to keep
23   the default value of 1 even on platforms that are unaffected by
24   CVE-2018-3639, in order to comply with the recommendation in the spec
25   regarding workaround discovery.
26
27-  ``DYNAMIC_WORKAROUND_CVE_2018_3639``: Enables dynamic mitigation for
28   `CVE-2018-3639`_. This build option should be set to 1 if the target
29   platform contains at least 1 CPU that requires dynamic mitigation.
30   Defaults to 0.
31
32-  ``WORKAROUND_CVE_2022_23960``: Enables mitigation for `CVE-2022-23960`_.
33   This build option should be set to 1 if the target platform contains at
34   least 1 CPU that requires this mitigation. Defaults to 1.
35
36.. _arm_cpu_macros_errata_workarounds:
37
38CPU Errata Workarounds
39----------------------
40
41TF-A exports a series of build flags which control the errata workarounds that
42are applied to each CPU by the reset handler. The errata details can be found
43in the CPU specific errata documents published by Arm:
44
45-  `Cortex-A53 MPCore Software Developers Errata Notice`_
46-  `Cortex-A57 MPCore Software Developers Errata Notice`_
47-  `Cortex-A72 MPCore Software Developers Errata Notice`_
48
49The errata workarounds are implemented for a particular revision or a set of
50processor revisions. This is checked by the reset handler at runtime. Each
51errata workaround is identified by its ``ID`` as specified in the processor's
52errata notice document. The format of the define used to enable/disable the
53errata workaround is ``ERRATA_<Processor name>_<ID>``, where the ``Processor name``
54is for example ``A57`` for the ``Cortex_A57`` CPU.
55
56Refer to :ref:`firmware_design_cpu_errata_reporting` for information on how to
57write errata workaround functions.
58
59All workarounds are disabled by default. The platform is responsible for
60enabling these workarounds according to its requirement by defining the
61errata workaround build flags in the platform specific makefile. In case
62these workarounds are enabled for the wrong CPU revision then the errata
63workaround is not applied. In the DEBUG build, this is indicated by
64printing a warning to the crash console.
65
66In the current implementation, a platform which has more than 1 variant
67with different revisions of a processor has no runtime mechanism available
68for it to specify which errata workarounds should be enabled or not.
69
70The value of the build flags is 0 by default, that is, disabled. A value of 1
71will enable it.
72
73For Cortex-A9, the following errata build flags are defined :
74
75-  ``ERRATA_A9_794073``: This applies errata 794073 workaround to Cortex-A9
76   CPU. This needs to be enabled for all revisions of the CPU.
77
78For Cortex-A15, the following errata build flags are defined :
79
80-  ``ERRATA_A15_816470``: This applies errata 816470 workaround to Cortex-A15
81   CPU. This needs to be enabled only for revision >= r3p0 of the CPU.
82
83-  ``ERRATA_A15_827671``: This applies errata 827671 workaround to Cortex-A15
84   CPU. This needs to be enabled only for revision >= r3p0 of the CPU.
85
86For Cortex-A17, the following errata build flags are defined :
87
88-  ``ERRATA_A17_852421``: This applies errata 852421 workaround to Cortex-A17
89   CPU. This needs to be enabled only for revision <= r1p2 of the CPU.
90
91-  ``ERRATA_A17_852423``: This applies errata 852423 workaround to Cortex-A17
92   CPU. This needs to be enabled only for revision <= r1p2 of the CPU.
93
94For Cortex-A35, the following errata build flags are defined :
95
96-  ``ERRATA_A35_855472``: This applies errata 855472 workaround to Cortex-A35
97   CPUs. This needs to be enabled only for revision r0p0 of Cortex-A35.
98
99For Cortex-A53, the following errata build flags are defined :
100
101-  ``ERRATA_A53_819472``: This applies errata 819472 workaround to all
102   CPUs. This needs to be enabled only for revision <= r0p1 of Cortex-A53.
103
104-  ``ERRATA_A53_824069``: This applies errata 824069 workaround to all
105   CPUs. This needs to be enabled only for revision <= r0p2 of Cortex-A53.
106
107-  ``ERRATA_A53_826319``: This applies errata 826319 workaround to Cortex-A53
108   CPU. This needs to be enabled only for revision <= r0p2 of the CPU.
109
110-  ``ERRATA_A53_827319``: This applies errata 827319 workaround to all
111   CPUs. This needs to be enabled only for revision <= r0p2 of Cortex-A53.
112
113-  ``ERRATA_A53_835769``: This applies erratum 835769 workaround at compile and
114   link time to Cortex-A53 CPU. This needs to be enabled for some variants of
115   revision <= r0p4. This workaround can lead the linker to create ``*.stub``
116   sections.
117
118-  ``ERRATA_A53_836870``: This applies errata 836870 workaround to Cortex-A53
119   CPU. This needs to be enabled only for revision <= r0p3 of the CPU. From
120   r0p4 and onwards, this errata is enabled by default in hardware.
121
122-  ``ERRATA_A53_843419``: This applies erratum 843419 workaround at link time
123   to Cortex-A53 CPU.  This needs to be enabled for some variants of revision
124   <= r0p4. This workaround can lead the linker to emit ``*.stub`` sections
125   which are 4kB aligned.
126
127-  ``ERRATA_A53_855873``: This applies errata 855873 workaround to Cortex-A53
128   CPUs. Though the erratum is present in every revision of the CPU,
129   this workaround is only applied to CPUs from r0p3 onwards, which feature
130   a chicken bit in CPUACTLR_EL1 to enable a hardware workaround.
131   Earlier revisions of the CPU have other errata which require the same
132   workaround in software, so they should be covered anyway.
133
134-  ``ERRATA_A53_1530924``: This applies errata 1530924 workaround to all
135   revisions of Cortex-A53 CPU.
136
137For Cortex-A55, the following errata build flags are defined :
138
139-  ``ERRATA_A55_768277``: This applies errata 768277 workaround to Cortex-A55
140   CPU. This needs to be enabled only for revision r0p0 of the CPU.
141
142-  ``ERRATA_A55_778703``: This applies errata 778703 workaround to Cortex-A55
143   CPU. This needs to be enabled only for revision r0p0 of the CPU.
144
145-  ``ERRATA_A55_798797``: This applies errata 798797 workaround to Cortex-A55
146   CPU. This needs to be enabled only for revision r0p0 of the CPU.
147
148-  ``ERRATA_A55_846532``: This applies errata 846532 workaround to Cortex-A55
149   CPU. This needs to be enabled only for revision <= r0p1 of the CPU.
150
151-  ``ERRATA_A55_903758``: This applies errata 903758 workaround to Cortex-A55
152   CPU. This needs to be enabled only for revision <= r0p1 of the CPU.
153
154-  ``ERRATA_A55_1221012``: This applies errata 1221012 workaround to Cortex-A55
155   CPU. This needs to be enabled only for revision <= r1p0 of the CPU.
156
157-  ``ERRATA_A55_1530923``: This applies errata 1530923 workaround to all
158   revisions of Cortex-A55 CPU.
159
160For Cortex-A57, the following errata build flags are defined :
161
162-  ``ERRATA_A57_806969``: This applies errata 806969 workaround to Cortex-A57
163   CPU. This needs to be enabled only for revision r0p0 of the CPU.
164
165-  ``ERRATA_A57_813419``: This applies errata 813419 workaround to Cortex-A57
166   CPU. This needs to be enabled only for revision r0p0 of the CPU.
167
168-  ``ERRATA_A57_813420``: This applies errata 813420 workaround to Cortex-A57
169   CPU. This needs to be enabled only for revision r0p0 of the CPU.
170
171-  ``ERRATA_A57_814670``: This applies errata 814670 workaround to Cortex-A57
172   CPU. This needs to be enabled only for revision r0p0 of the CPU.
173
174-  ``ERRATA_A57_817169``: This applies errata 817169 workaround to Cortex-A57
175   CPU. This needs to be enabled only for revision <= r0p1 of the CPU.
176
177-  ``ERRATA_A57_826974``: This applies errata 826974 workaround to Cortex-A57
178   CPU. This needs to be enabled only for revision <= r1p1 of the CPU.
179
180-  ``ERRATA_A57_826977``: This applies errata 826977 workaround to Cortex-A57
181   CPU. This needs to be enabled only for revision <= r1p1 of the CPU.
182
183-  ``ERRATA_A57_828024``: This applies errata 828024 workaround to Cortex-A57
184   CPU. This needs to be enabled only for revision <= r1p1 of the CPU.
185
186-  ``ERRATA_A57_829520``: This applies errata 829520 workaround to Cortex-A57
187   CPU. This needs to be enabled only for revision <= r1p2 of the CPU.
188
189-  ``ERRATA_A57_833471``: This applies errata 833471 workaround to Cortex-A57
190   CPU. This needs to be enabled only for revision <= r1p2 of the CPU.
191
192-  ``ERRATA_A57_859972``: This applies errata 859972 workaround to Cortex-A57
193   CPU. This needs to be enabled only for revision <= r1p3 of the CPU.
194
195-  ``ERRATA_A57_1319537``: This applies errata 1319537 workaround to all
196   revisions of Cortex-A57 CPU.
197
198For Cortex-A72, the following errata build flags are defined :
199
200-  ``ERRATA_A72_859971``: This applies errata 859971 workaround to Cortex-A72
201   CPU. This needs to be enabled only for revision <= r0p3 of the CPU.
202
203-  ``ERRATA_A72_1319367``: This applies errata 1319367 workaround to all
204   revisions of Cortex-A72 CPU.
205
206For Cortex-A73, the following errata build flags are defined :
207
208-  ``ERRATA_A73_852427``: This applies errata 852427 workaround to Cortex-A73
209   CPU. This needs to be enabled only for revision r0p0 of the CPU.
210
211-  ``ERRATA_A73_855423``: This applies errata 855423 workaround to Cortex-A73
212   CPU. This needs to be enabled only for revision <= r0p1 of the CPU.
213
214For Cortex-A75, the following errata build flags are defined :
215
216-  ``ERRATA_A75_764081``: This applies errata 764081 workaround to Cortex-A75
217   CPU. This needs to be enabled only for revision r0p0 of the CPU.
218
219-  ``ERRATA_A75_790748``: This applies errata 790748 workaround to Cortex-A75
220    CPU. This needs to be enabled only for revision r0p0 of the CPU.
221
222For Cortex-A76, the following errata build flags are defined :
223
224-  ``ERRATA_A76_1073348``: This applies errata 1073348 workaround to Cortex-A76
225   CPU. This needs to be enabled only for revision <= r1p0 of the CPU.
226
227-  ``ERRATA_A76_1130799``: This applies errata 1130799 workaround to Cortex-A76
228   CPU. This needs to be enabled only for revision <= r2p0 of the CPU.
229
230-  ``ERRATA_A76_1220197``: This applies errata 1220197 workaround to Cortex-A76
231   CPU. This needs to be enabled only for revision <= r2p0 of the CPU.
232
233-  ``ERRATA_A76_1257314``: This applies errata 1257314 workaround to Cortex-A76
234   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
235
236-  ``ERRATA_A76_1262606``: This applies errata 1262606 workaround to Cortex-A76
237   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
238
239-  ``ERRATA_A76_1262888``: This applies errata 1262888 workaround to Cortex-A76
240   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
241
242-  ``ERRATA_A76_1275112``: This applies errata 1275112 workaround to Cortex-A76
243   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
244
245-  ``ERRATA_A76_1791580``: This applies errata 1791580 workaround to Cortex-A76
246   CPU. This needs to be enabled only for revision <= r4p0 of the CPU.
247
248-  ``ERRATA_A76_1165522``: This applies errata 1165522 workaround to all
249   revisions of Cortex-A76 CPU. This errata is fixed in r3p0 but due to
250   limitation of errata framework this errata is applied to all revisions
251   of Cortex-A76 CPU.
252
253-  ``ERRATA_A76_1868343``: This applies errata 1868343 workaround to Cortex-A76
254   CPU. This needs to be enabled only for revision <= r4p0 of the CPU.
255
256-  ``ERRATA_A76_1946160``: This applies errata 1946160 workaround to Cortex-A76
257   CPU. This needs to be enabled only for revisions r3p0 - r4p1 of the CPU.
258
259For Cortex-A77, the following errata build flags are defined :
260
261-  ``ERRATA_A77_1508412``: This applies errata 1508412 workaround to Cortex-A77
262   CPU. This needs to be enabled only for revision <= r1p0 of the CPU.
263
264-  ``ERRATA_A77_1925769``: This applies errata 1925769 workaround to Cortex-A77
265   CPU. This needs to be enabled only for revision <= r1p1 of the CPU.
266
267-  ``ERRATA_A77_1946167``: This applies errata 1946167 workaround to Cortex-A77
268   CPU. This needs to be enabled only for revision <= r1p1 of the CPU.
269
270-  ``ERRATA_A77_1791578``: This applies errata 1791578 workaround to Cortex-A77
271   CPU. This needs to be enabled for r0p0, r1p0, and r1p1, it is still open.
272
273-  ``ERRATA_A77_2356587``: This applies errata 2356587 workaround to Cortex-A77
274   CPU. This needs to be enabled for r0p0, r1p0, and r1p1, it is still open.
275
276For Cortex-A78, the following errata build flags are defined :
277
278-  ``ERRATA_A78_1688305``: This applies errata 1688305 workaround to Cortex-A78
279   CPU. This needs to be enabled only for revision r0p0 - r1p0 of the CPU.
280
281-  ``ERRATA_A78_1941498``: This applies errata 1941498 workaround to Cortex-A78
282   CPU. This needs to be enabled for revisions r0p0, r1p0, and r1p1 of the CPU.
283
284-  ``ERRATA_A78_1951500``: This applies errata 1951500 workaround to Cortex-A78
285   CPU. This needs to be enabled for revisions r1p0 and r1p1, r0p0 has the same
286   issue but there is no workaround for that revision.
287
288-  ``ERRATA_A78_1821534``: This applies errata 1821534 workaround to Cortex-A78
289   CPU. This needs to be enabled for revisions r0p0 and r1p0.
290
291-  ``ERRATA_A78_1952683``: This applies errata 1952683 workaround to Cortex-A78
292   CPU. This needs to be enabled for revision r0p0, it is fixed in r1p0.
293
294-  ``ERRATA_A78_2132060``: This applies errata 2132060 workaround to Cortex-A78
295   CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1, and r1p2. It
296   is still open.
297
298-  ``ERRATA_A78_2242635``: This applies errata 2242635 workaround to Cortex-A78
299   CPU. This needs to be enabled for revisions r1p0, r1p1, and r1p2. The issue
300   is present in r0p0 but there is no workaround. It is still open.
301
302-  ``ERRATA_A78_2376745``: This applies errata 2376745 workaround to Cortex-A78
303   CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1, and r1p2, and
304   it is still open.
305
306-  ``ERRATA_A78_2395406``: This applies errata 2395406 workaround to Cortex-A78
307   CPU. This needs to be enabled for revisions r0p0, r1p0, r1p1, and r1p2, and
308   it is still open.
309
310For Cortex-A78 AE, the following errata build flags are defined :
311
312- ``ERRATA_A78_AE_1941500`` : This applies errata 1941500 workaround to
313   Cortex-A78 AE CPU. This needs to be enabled for revisions r0p0 and r0p1.
314   This erratum is still open.
315
316- ``ERRATA_A78_AE_1951502`` : This applies errata 1951502 workaround to
317  Cortex-A78 AE CPU. This needs to be enabled for revisions r0p0 and r0p1. This
318  erratum is still open.
319
320- ``ERRATA_A78_AE_2376748`` : This applies errata 2376748 workaround to
321  Cortex-A78 AE CPU. This needs to be enabled for revisions r0p0 and r0p1. This
322  erratum is still open.
323
324- ``ERRATA_A78_AE_2395408`` : This applies errata 2395408 workaround to
325  Cortex-A78 AE CPU. This needs to be enabled for revisions r0p0 and r0p1. This
326  erratum is still open.
327
328For Cortex-A78C, the following errata build flags are defined :
329
330- ``ERRATA_A78C_2132064`` : This applies errata 2132064 workaround to
331  Cortex-A78C CPU. This needs to be enabled for revisions r0p1, r0p2 and
332  it is still open.
333
334- ``ERRATA_A78C_2242638`` : This applies errata 2242638 workaround to
335  Cortex-A78C CPU. This needs to be enabled for revisions r0p1, r0p2 and
336  it is still open.
337
338- ``ERRATA_A78C_2376749`` : This applies errata 2376749 workaround to
339  Cortex-A78C CPU. This needs to be enabled for revisions r0p1 and r0p2. This
340  erratum is still open.
341
342- ``ERRATA_A78C_2395411`` : This applies errata 2395411 workaround to
343  Cortex-A78C CPU. This needs to be enabled for revisions r0p1 and r0p2. This
344  erratum is still open.
345
346For Cortex-X1 CPU, the following errata build flags are defined:
347
348- ``ERRATA_X1_1821534`` : This applies errata 1821534 workaround to Cortex-X1
349   CPU. This needs to be enabled only for revision <= r1p0 of the CPU.
350
351- ``ERRATA_X1_1688305`` : This applies errata 1688305 workaround to Cortex-X1
352   CPU. This needs to be enabled only for revision <= r1p0 of the CPU.
353
354- ``ERRATA_X1_1827429`` : This applies errata 1827429 workaround to Cortex-X1
355   CPU. This needs to be enabled only for revision <= r1p0 of the CPU.
356
357For Neoverse N1, the following errata build flags are defined :
358
359-  ``ERRATA_N1_1073348``: This applies errata 1073348 workaround to Neoverse-N1
360   CPU. This needs to be enabled only for revision r0p0 and r1p0 of the CPU.
361
362-  ``ERRATA_N1_1130799``: This applies errata 1130799 workaround to Neoverse-N1
363   CPU. This needs to be enabled only for revision <= r2p0 of the CPU.
364
365-  ``ERRATA_N1_1165347``: This applies errata 1165347 workaround to Neoverse-N1
366   CPU. This needs to be enabled only for revision <= r2p0 of the CPU.
367
368-  ``ERRATA_N1_1207823``: This applies errata 1207823 workaround to Neoverse-N1
369   CPU. This needs to be enabled only for revision <= r2p0 of the CPU.
370
371-  ``ERRATA_N1_1220197``: This applies errata 1220197 workaround to Neoverse-N1
372   CPU. This needs to be enabled only for revision <= r2p0 of the CPU.
373
374-  ``ERRATA_N1_1257314``: This applies errata 1257314 workaround to Neoverse-N1
375   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
376
377-  ``ERRATA_N1_1262606``: This applies errata 1262606 workaround to Neoverse-N1
378   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
379
380-  ``ERRATA_N1_1262888``: This applies errata 1262888 workaround to Neoverse-N1
381   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
382
383-  ``ERRATA_N1_1275112``: This applies errata 1275112 workaround to Neoverse-N1
384   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
385
386-  ``ERRATA_N1_1315703``: This applies errata 1315703 workaround to Neoverse-N1
387   CPU. This needs to be enabled only for revision <= r3p0 of the CPU.
388
389-  ``ERRATA_N1_1542419``: This applies errata 1542419 workaround to Neoverse-N1
390   CPU. This needs to be enabled only for revisions r3p0 - r4p0 of the CPU.
391
392-  ``ERRATA_N1_1868343``: This applies errata 1868343 workaround to Neoverse-N1
393   CPU. This needs to be enabled only for revision <= r4p0 of the CPU.
394
395-  ``ERRATA_N1_1946160``: This applies errata 1946160 workaround to Neoverse-N1
396   CPU. This needs to be enabled for revisions r3p0, r3p1, r4p0, and r4p1, for
397   revisions r0p0, r1p0, and r2p0 there is no workaround.
398
399For Neoverse V1, the following errata build flags are defined :
400
401-  ``ERRATA_V1_1618635``: This applies errata 1618635 workaround to Neoverse-V1
402   CPU. This needs to be enabled for revision r0p0 of the CPU, it is fixed in
403   r1p0.
404
405-  ``ERRATA_V1_1774420``: This applies errata 1774420 workaround to Neoverse-V1
406   CPU. This needs to be enabled only for revisions r0p0 and r1p0, it is fixed
407   in r1p1.
408
409-  ``ERRATA_V1_1791573``: This applies errata 1791573 workaround to Neoverse-V1
410   CPU. This needs to be enabled only for revisions r0p0 and r1p0, it is fixed
411   in r1p1.
412
413-  ``ERRATA_V1_1852267``: This applies errata 1852267 workaround to Neoverse-V1
414   CPU. This needs to be enabled only for revisions r0p0 and r1p0, it is fixed
415   in r1p1.
416
417-  ``ERRATA_V1_1925756``: This applies errata 1925756 workaround to Neoverse-V1
418   CPU. This needs to be enabled for r0p0, r1p0, and r1p1, it is still open.
419
420-  ``ERRATA_V1_1940577``: This applies errata 1940577 workaround to Neoverse-V1
421   CPU. This needs to be enabled only for revision r1p0 and r1p1 of the
422   CPU.
423
424-  ``ERRATA_V1_1966096``: This applies errata 1966096 workaround to Neoverse-V1
425   CPU. This needs to be enabled for revisions r1p0 and r1p1 of the CPU, the
426   issue is present in r0p0 as well but there is no workaround for that
427   revision.  It is still open.
428
429-  ``ERRATA_V1_2139242``: This applies errata 2139242 workaround to Neoverse-V1
430   CPU. This needs to be enabled for revisions r0p0, r1p0, and r1p1 of the
431   CPU.  It is still open.
432
433-  ``ERRATA_V1_2108267``: This applies errata 2108267 workaround to Neoverse-V1
434   CPU. This needs to be enabled for revisions r0p0, r1p0, and r1p1 of the CPU.
435   It is still open.
436
437-  ``ERRATA_V1_2216392``: This applies errata 2216392 workaround to Neoverse-V1
438   CPU. This needs to be enabled for revisions r1p0 and r1p1 of the CPU, the
439   issue is present in r0p0 as well but there is no workaround for that
440   revision.  It is still open.
441
442-  ``ERRATA_V1_2294912``: This applies errata 2294912 workaround to Neoverse-V1
443   CPU. This needs to be enabled for revisions r0p0, r1p0, and r1p1 of the CPU.
444
445-  ``ERRATA_V1_2372203``: This applies errata 2372203 workaround to Neoverse-V1
446   CPU. This needs to be enabled for revisions r0p0, r1p0 and r1p1 of the CPU.
447   It is still open.
448
449For Cortex-A710, the following errata build flags are defined :
450
451-  ``ERRATA_A710_1987031``: This applies errata 1987031 workaround to
452   Cortex-A710 CPU. This needs to be enabled only for revisions r0p0, r1p0 and
453   r2p0 of the CPU. It is still open.
454
455-  ``ERRATA_A710_2081180``: This applies errata 2081180 workaround to
456   Cortex-A710 CPU. This needs to be enabled only for revisions r0p0, r1p0 and
457   r2p0 of the CPU. It is still open.
458
459-  ``ERRATA_A710_2055002``: This applies errata 2055002 workaround to
460   Cortex-A710 CPU. This needs to be enabled for revisions r1p0, r2p0 of the CPU
461   and is still open.
462
463-  ``ERRATA_A710_2017096``: This applies errata 2017096 workaround to
464   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
465   of the CPU and is still open.
466
467-  ``ERRATA_A710_2083908``: This applies errata 2083908 workaround to
468   Cortex-A710 CPU. This needs to be enabled for revision r2p0 of the CPU and
469   is still open.
470
471-  ``ERRATA_A710_2058056``: This applies errata 2058056 workaround to
472   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
473   of the CPU and is still open.
474
475-  ``ERRATA_A710_2267065``: This applies errata 2267065 workaround to
476   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
477   of the CPU and is fixed in r2p1.
478
479-  ``ERRATA_A710_2136059``: This applies errata 2136059 workaround to
480   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
481   of the CPU and is fixed in r2p1.
482
483-  ``ERRATA_A710_2147715``: This applies errata 2147715 workaround to
484   Cortex-A710 CPU. This needs to be enabled for revision r2p0 of the CPU
485   and is fixed in r2p1.
486
487-  ``ERRATA_A710_2216384``: This applies errata 2216384 workaround to
488   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
489   of the CPU and is fixed in r2p1.
490
491-  ``ERRATA_A710_2282622``: This applies errata 2282622 workaround to
492   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
493   of the CPU and is fixed in r2p1.
494
495-  ``ERRATA_A710_2008768``: This applies errata 2008768 workaround to
496   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
497   of the CPU and is fixed in r2p1.
498
499-  ``ERRATA_A710_2371105``: This applies errata 2371105 workaround to
500   Cortex-A710 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
501   of the CPU and is fixed in r2p1.
502
503For Neoverse N2, the following errata build flags are defined :
504
505-  ``ERRATA_N2_2002655``: This applies errata 2002655 workaround to Neoverse-N2
506   CPU. This needs to be enabled for revision r0p0 of the CPU, it is still open.
507
508-  ``ERRATA_N2_2067956``: This applies errata 2067956 workaround to Neoverse-N2
509   CPU. This needs to be enabled for revision r0p0 of the CPU and is still open.
510
511-  ``ERRATA_N2_2025414``: This applies errata 2025414 workaround to Neoverse-N2
512   CPU. This needs to be enabled for revision r0p0 of the CPU and is still open.
513
514-  ``ERRATA_N2_2189731``: This applies errata 2189731 workaround to Neoverse-N2
515   CPU. This needs to be enabled for revision r0p0 of the CPU and is still open.
516
517-  ``ERRATA_N2_2138956``: This applies errata 2138956 workaround to Neoverse-N2
518   CPU. This needs to be enabled for revision r0p0 of the CPU and is still open.
519
520-  ``ERRATA_N2_2138953``: This applies errata 2138953 workaround to Neoverse-N2
521   CPU. This needs to be enabled for revision r0p0 of the CPU and is still open.
522
523-  ``ERRATA_N2_2242415``: This applies errata 2242415 workaround to Neoverse-N2
524   CPU. This needs to be enabled for revision r0p0 of the CPU and is still open.
525
526-  ``ERRATA_N2_2138958``: This applies errata 2138958 workaround to Neoverse-N2
527   CPU. This needs to be enabled for revision r0p0 of the CPU and is still open.
528
529-  ``ERRATA_N2_2242400``: This applies errata 2242400 workaround to Neoverse-N2
530   CPU. This needs to be enabled for revision r0p0 of the CPU and is still open.
531
532-  ``ERRATA_N2_2280757``: This applies errata 2280757 workaround to Neoverse-N2
533   CPU. This needs to be enabled for revision r0p0 of the CPU and is still open.
534
535-  ``ERRATA_N2_2376738``: This applies errata 2376738 workaround to Neoverse-N2
536   CPU. This needs to be enabled for revision r0p0 of the CPU, it is fixed in
537   r0p1.
538
539-  ``ERRATA_N2_2388450``: This applies errata 2388450 workaround to Neoverse-N2
540   CPU. This needs to be enabled for revision r0p0 of the CPU, it is fixed in
541   r0p1.
542
543For Cortex-X2, the following errata build flags are defined :
544
545-  ``ERRATA_X2_2002765``: This applies errata 2002765 workaround to Cortex-X2
546   CPU. This needs to be enabled for revisions r0p0, r1p0, and r2p0 of the CPU,
547   it is still open.
548
549-  ``ERRATA_X2_2058056``: This applies errata 2058056 workaround to Cortex-X2
550   CPU. This needs to be enabled for revisions r0p0, r1p0, and r2p0 of the CPU,
551   it is still open.
552
553-  ``ERRATA_X2_2083908``: This applies errata 2083908 workaround to Cortex-X2
554   CPU. This needs to be enabled for revision r2p0 of the CPU, it is still open.
555
556-  ``ERRATA_X2_2017096``: This applies errata 2017096 workaround to
557   Cortex-X2 CPU. This needs to be enabled only for revisions r0p0, r1p0 and
558   r2p0 of the CPU, it is fixed in r2p1.
559
560-  ``ERRATA_X2_2081180``: This applies errata 2081180 workaround to
561   Cortex-X2 CPU. This needs to be enabled only for revisions r0p0, r1p0 and
562   r2p0 of the CPU, it is fixed in r2p1.
563
564-  ``ERRATA_X2_2216384``: This applies errata 2216384 workaround to
565   Cortex-X2 CPU. This needs to be enabled only for revisions r0p0, r1p0 and
566   r2p0 of the CPU, it is fixed in r2p1.
567
568-  ``ERRATA_X2_2147715``: This applies errata 2147715 workaround to
569   Cortex-X2 CPU. This needs to be enabled only for revision r2p0 of the CPU,
570   it is fixed in r2p1.
571
572-  ``ERRATA_X2_2371105``: This applies errata 2371105 workaround to
573   Cortex-X2 CPU. This needs to be enabled for revisions r0p0, r1p0 and r2p0
574   of the CPU and is fixed in r2p1.
575
576For Cortex-A510, the following errata build flags are defined :
577
578-  ``ERRATA_A510_1922240``: This applies errata 1922240 workaround to
579   Cortex-A510 CPU. This needs to be enabled only for revision r0p0, it is
580   fixed in r0p1.
581
582-  ``ERRATA_A510_2288014``: This applies errata 2288014 workaround to
583   Cortex-A510 CPU. This needs to be enabled only for revisions r0p0, r0p1,
584   r0p2, r0p3 and r1p0, it is fixed in r1p1.
585
586-  ``ERRATA_A510_2042739``: This applies errata 2042739 workaround to
587   Cortex-A510 CPU. This needs to be enabled only for revisions r0p0, r0p1 and
588   r0p2, it is fixed in r0p3.
589
590-  ``ERRATA_A510_2041909``: This applies errata 2041909 workaround to
591   Cortex-A510 CPU. This needs to be enabled only for revision r0p2 and is fixed
592   in r0p3. The issue is also present in r0p0 and r0p1 but there is no
593   workaround for those revisions.
594
595-  ``ERRATA_A510_2250311``: This applies errata 2250311 workaround to
596   Cortex-A510 CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2,
597   r0p3 and r1p0, it is fixed in r1p1. This workaround disables MPMM even if
598   ENABLE_MPMM=1.
599
600-  ``ERRATA_A510_2218950``: This applies errata 2218950 workaround to
601   Cortex-A510 CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2,
602   r0p3 and r1p0, it is fixed in r1p1.
603
604-  ``ERRATA_A510_2172148``: This applies errata 2172148 workaround to
605   Cortex-A510 CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2,
606   r0p3 and r1p0, it is fixed in r1p1.
607
608- ``ERRATA_A510_2347730``: This applies errata 2347730 workaround to
609   Cortex-A510 CPU. This needs to be enabled for revisions r0p0, r0p1, r0p2,
610   r0p3, r1p0 and r1p1. It is fixed in r1p2.
611
612-  ``ERRATA_A510_2371937``: This applies errata 2371937 workaround to
613   Cortex-A510 CPU. This needs to applied for revisions r0p0, r0p1, r0p2,
614   r0p3, r1p0, r1p1, and is fixed in r1p2.
615
616DSU Errata Workarounds
617----------------------
618
619Similar to CPU errata, TF-A also implements workarounds for DSU (DynamIQ
620Shared Unit) errata. The DSU errata details can be found in the respective Arm
621documentation:
622
623- `Arm DSU Software Developers Errata Notice`_.
624
625Each erratum is identified by an ``ID``, as defined in the DSU errata notice
626document. Thus, the build flags which enable/disable the errata workarounds
627have the format ``ERRATA_DSU_<ID>``. The implementation and application logic
628of DSU errata workarounds are similar to `CPU errata workarounds`_.
629
630For DSU errata, the following build flags are defined:
631
632-  ``ERRATA_DSU_798953``: This applies errata 798953 workaround for the
633   affected DSU configurations. This errata applies only for those DSUs that
634   revision is r0p0 (on r0p1 it is fixed). However, please note that this
635   workaround results in increased DSU power consumption on idle.
636
637-  ``ERRATA_DSU_936184``: This applies errata 936184 workaround for the
638   affected DSU configurations. This errata applies only for those DSUs that
639   contain the ACP interface **and** the DSU revision is older than r2p0 (on
640   r2p0 it is fixed). However, please note that this workaround results in
641   increased DSU power consumption on idle.
642
643-  ``ERRATA_DSU_2313941``: This applies errata 2313941 workaround for the
644   affected DSU configurations. This errata applies for those DSUs with
645   revisions r0p0, r1p0, r2p0, r2p1, r3p0, r3p1 and is still open. However,
646   please note that this workaround results in increased DSU power consumption
647   on idle.
648
649CPU Specific optimizations
650--------------------------
651
652This section describes some of the optimizations allowed by the CPU micro
653architecture that can be enabled by the platform as desired.
654
655-  ``SKIP_A57_L1_FLUSH_PWR_DWN``: This flag enables an optimization in the
656   Cortex-A57 cluster power down sequence by not flushing the Level 1 data
657   cache. The L1 data cache and the L2 unified cache are inclusive. A flush
658   of the L2 by set/way flushes any dirty lines from the L1 as well. This
659   is a known safe deviation from the Cortex-A57 TRM defined power down
660   sequence. Each Cortex-A57 based platform must make its own decision on
661   whether to use the optimization.
662
663-  ``A53_DISABLE_NON_TEMPORAL_HINT``: This flag disables the cache non-temporal
664   hint. The LDNP/STNP instructions as implemented on Cortex-A53 do not behave
665   in a way most programmers expect, and will most probably result in a
666   significant speed degradation to any code that employs them. The Armv8-A
667   architecture (see Arm DDI 0487A.h, section D3.4.3) allows cores to ignore
668   the non-temporal hint and treat LDNP/STNP as LDP/STP instead. Enabling this
669   flag enforces this behaviour. This needs to be enabled only for revisions
670   <= r0p3 of the CPU and is enabled by default.
671
672-  ``A57_DISABLE_NON_TEMPORAL_HINT``: This flag has the same behaviour as
673   ``A53_DISABLE_NON_TEMPORAL_HINT`` but for Cortex-A57. This needs to be
674   enabled only for revisions <= r1p2 of the CPU and is enabled by default,
675   as recommended in section "4.7 Non-Temporal Loads/Stores" of the
676   `Cortex-A57 Software Optimization Guide`_.
677
678- ''A57_ENABLE_NON_CACHEABLE_LOAD_FWD'': This flag enables non-cacheable
679   streaming enhancement feature for Cortex-A57 CPUs. Platforms can set
680   this bit only if their memory system meets the requirement that cache
681   line fill requests from the Cortex-A57 processor are atomic. Each
682   Cortex-A57 based platform must make its own decision on whether to use
683   the optimization. This flag is disabled by default.
684
685-  ``NEOVERSE_Nx_EXTERNAL_LLC``: This flag indicates that an external last
686   level cache(LLC) is present in the system, and that the DataSource field
687   on the master CHI interface indicates when data is returned from the LLC.
688   This is used to control how the LL_CACHE* PMU events count.
689   Default value is 0 (Disabled).
690
691GIC Errata Workarounds
692----------------------
693-  ``GIC600_ERRATA_WA_2384374``: This flag applies part 2 of errata 2384374
694   workaround for the affected GIC600 and GIC600-AE implementations. It applies
695   to implementations of GIC600 and GIC600-AE with revisions less than or equal
696   to r1p6 and r0p2 respectively. If the platform sets GICV3_SUPPORT_GIC600,
697   then this flag is enabled; otherwise, it is 0 (Disabled).
698
699--------------
700
701*Copyright (c) 2014-2022, Arm Limited and Contributors. All rights reserved.*
702
703.. _CVE-2017-5715: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-5715
704.. _CVE-2018-3639: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-3639
705.. _CVE-2022-23960: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-23960
706.. _Cortex-A53 MPCore Software Developers Errata Notice: http://infocenter.arm.com/help/topic/com.arm.doc.epm048406/index.html
707.. _Cortex-A57 MPCore Software Developers Errata Notice: http://infocenter.arm.com/help/topic/com.arm.doc.epm049219/index.html
708.. _Cortex-A72 MPCore Software Developers Errata Notice: http://infocenter.arm.com/help/topic/com.arm.doc.epm012079/index.html
709.. _Cortex-A57 Software Optimization Guide: http://infocenter.arm.com/help/topic/com.arm.doc.uan0015b/Cortex_A57_Software_Optimization_Guide_external.pdf
710.. _Arm DSU Software Developers Errata Notice: http://infocenter.arm.com/help/topic/com.arm.doc.epm138168/index.html
711