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CSR Bit Fields

RISC-V mstateen0h CSR Register

Address 0x31CPrivilege MachineAccess RW / RV32 high-half / 32-bitMachine delegation, environment-configuration, and state-enable CSRs

mstateen0h at 0x31C is a State-enable control CSR: is a standard named CSR in the RV32 high-half mstateen category.

Bit Overview
bit 3 = only bit 3; bits 12..11 = bits 12 down to 11
MSBLSB
Reserved63:32VALUE31:0RW
Field Map

Understand mstateen0h By Bit Fields

1 key fields
31:0

VALUE

RW

Full register value of mstateen0h; 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 31:0) — Full register value of mstateen0h; 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 mstateen0h; 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.

What To Check First When Reading This CSR

  • - First confirm that the current hart implements mstateen0h; unimplemented or insufficiently privileged accesses raise an illegal-instruction exception.
  • - Use address 0x31C and the lowest access privilege (Machine) 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

  • - Preserve bits that are not being changed so reserved or implementation-defined fields are not written with invalid values.
  • - Prefer CSRRS/CSRRC for local set/clear operations to avoid CSRRW overwriting concurrently updated status bits.

Put It Back Into A Real Flow

1

During initialization or the relevant privileged flow, software reads mstateen0h to observe the current state.

2

Modify only the target fields while preserving all other bits.

3

Read back the CSR or validate through later trap, interrupt, or context-switch behavior that the setting took effect.