Zicntr Extension

Versions

2.0.0

Architectural performance counters

This extension has the following implementation options:

TIME_CSR_IMPLEMENTED

Type	boolean
Valid Values	boolean
Description	Whether or not a real hardware time CSR exists. Implementations can either provide a real CSR or emulate access at M-mode. Possible values: true time/timeh exists, and accessing it will not cause an IllegalInstruction trap false time/timeh does not exist. Accessing the CSR will cause an IllegalInstruction trap or enter an unpredictable state, depending on TRAP_ON_UNIMPLEMENTED_CSR. Privileged software may emulate the time CSR, or may pass the exception to a lower level.

Type

boolean

Valid Values

boolean

Description

Whether or not a real hardware time CSR exists. Implementations can either provide a real CSR or emulate access at M-mode.

Possible values:

true: time/timeh exists, and accessing it will not cause an IllegalInstruction trap
false: time/timeh does not exist. Accessing the CSR will cause an IllegalInstruction trap or enter an unpredictable state, depending on TRAP_ON_UNIMPLEMENTED_CSR. Privileged software may emulate the time CSR, or may pass the exception to a lower level.