xref: /rk3399_ARM-atf/docs/components/activity-monitors.rst (revision 9cf75647235ad243acc7a585696ccb7b5ff54b36)
1*9cf75647SChris KayActivity Monitors
2*9cf75647SChris Kay=================
3*9cf75647SChris Kay
4*9cf75647SChris KayFEAT_AMUv1 of the Armv8-A architecture introduces the Activity Monitors
5*9cf75647SChris Kayextension. This extension describes the architecture for the Activity Monitor
6*9cf75647SChris KayUnit (|AMU|), an optional non-invasive component for monitoring core events
7*9cf75647SChris Kaythrough a set of 64-bit counters.
8*9cf75647SChris Kay
9*9cf75647SChris KayWhen the ``ENABLE_AMU=1`` build option is provided, Trusted Firmware-A sets up
10*9cf75647SChris Kaythe |AMU| prior to its exit from EL3, and will save and restore architected
11*9cf75647SChris Kay|AMU| counters as necessary upon suspend and resume.
12*9cf75647SChris Kay
13*9cf75647SChris Kay--------------
14*9cf75647SChris Kay
15*9cf75647SChris Kay*Copyright (c) 2021, Arm Limited. All rights reserved.*
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