tree 1ec594e7826f64e06157cfbe6dabf965fb03502e
parent bc50119a01eac709b5d26d2885e8743f0d8533f4
author Fuad Tabba <tabba@google.com> 1568824394 +0100
committer Fuad Tabba <tabba@google.com> 1569591164 +0100

Support for accessing performance monitoring registers

For now, the primary VM can access all performance monitoring registers, whereas
secondary VMs cannot.  Registers that enable counting or performance-related
interrupts are saved and switched, therefore, the primary VM cannot count events
or set interrupts for secondary VMs.

This code allows us in the future to add performance monitor support to
secondary VMs, and to have fine-grained control over which register accesses are
allowed, either by the primary or secondary, as well as change the behavior for
such accesses.

Bug: 132394973
Change-Id: I89c9f6658d30b8bca3c13ae99c3354f957fd0bb3