RVOPcode
Back To CSR WorkbenchView In Register Browser
CSR Bit Fields

RISC-V hpmcounter31 CSR Register

Address 0xC1FPrivilege UserAccess RO / XLENUser counters and performance-monitoring CSRs

hpmcounter31 is a user-level hardware performance-monitoring counter CSR for implementation-defined event counts.

Bit Overview
bit 3 = only bit 3; bits 12..11 = bits 12 down to 11
MSBLSB
VALUE63:0RO
Field Map

Understand hpmcounter31 By Bit Fields

1 key fields
XLEN-1:0

VALUE

RO

Full register value of hpmcounter31; bits not split out here follow the relevant extension or privileged specification, and reserved or WPRI fields should be preserved when writing other fields and ignored on reads.

VALUE (bits XLEN-1:0) — Full register value of hpmcounter31; bits not split out here follow the relevant extension or privileged specification, and reserved or WPRI fields should be preserved when writing other fields and ignored on reads.

What This Field Controls

  • - Full register value of hpmcounter31; bits not split out here follow the relevant extension or privileged specification, and reserved or WPRI fields should be preserved when writing other fields and ignored on reads.

Common Values

This field is better understood together with surrounding context than as a fixed memorized enumeration.

↗Open Official Manual

What To Check First When Reading This CSR

  • - First confirm that the current hart implements hpmcounter31; unimplemented or insufficiently privileged accesses raise an illegal-instruction exception.
  • - Use address 0xC1F and the lowest access privilege (User) to decide whether software may read it directly.
  • - Do not assume fixed values for reserved, WARL, or WLRL bits; interpret the value according to the specification and implementation.

Risk Checks Before Writing

  • - hpmcounter31 is a read-only CSR; writes raise an illegal-instruction exception or are disallowed by the implementation.

Put It Back Into A Real Flow

1

Read hpmcounter31 to obtain hardware or runtime state.

2

Interpret the returned value according to the field descriptions and do not attempt to write it back.

3

If reading fails at the current privilege level, handle the illegal-instruction exception path.