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-rw-r--r--Documentation/arm64/booting.rst14
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diff --git a/Documentation/arm64/booting.rst b/Documentation/arm64/booting.rst
index 5d78a6f5b0ae..a3f1a47b6f1c 100644
--- a/Documentation/arm64/booting.rst
+++ b/Documentation/arm64/booting.rst
@@ -248,6 +248,20 @@ Before jumping into the kernel, the following conditions must be met:
- HCR_EL2.APK (bit 40) must be initialised to 0b1
- HCR_EL2.API (bit 41) must be initialised to 0b1
+ For CPUs with Activity Monitors Unit v1 (AMUv1) extension present:
+ - If EL3 is present:
+ CPTR_EL3.TAM (bit 30) must be initialised to 0b0
+ CPTR_EL2.TAM (bit 30) must be initialised to 0b0
+ AMCNTENSET0_EL0 must be initialised to 0b1111
+ AMCNTENSET1_EL0 must be initialised to a platform specific value
+ having 0b1 set for the corresponding bit for each of the auxiliary
+ counters present.
+ - If the kernel is entered at EL1:
+ AMCNTENSET0_EL0 must be initialised to 0b1111
+ AMCNTENSET1_EL0 must be initialised to a platform specific value
+ having 0b1 set for the corresponding bit for each of the auxiliary
+ counters present.
+
The requirements described above for CPU mode, caches, MMUs, architected
timers, coherency and system registers apply to all CPUs. All CPUs must
enter the kernel in the same exception level.