mstatush

Machine Status High

The mstatus register tracks and controls the hart’s current operating state.

Attributes

CSR Address

0x310

Defining extension

Sm, version >= 1.12

Length

32-bit

Privilege Mode

M

Format

mstatush format

Figure 1. mstatush format

Field Summary

Name	Location	Type	Reset Value
`MPV`	7	RW-H	UNDEFINED_LEGAL
`GVA`	6	RW-H	0
`MBE`	5	RO	0
`SBE`	4	RO	0

Fields

`MPV`

Location: mstatush[7]
Description: Machine Previous Virtualization mode

Written with the prior virtualization mode when entering M-mode from an exception/interrupt. When returning via an MRET instruction, the virtualization mode becomes the value of MPV unless MPP=3, in which case the virtualization mode is always 0. Can also be written by software.
Type

RW-H	Read-Write with Hardware update Field is writable by software. Any value that fits in the field is acceptable. Hardware also updates the field without an explicit software write.

Reset value: UNDEFINED_LEGAL

`GVA`

Location: mstatush[6]
Description: Guest Virtual Address

When a trap is taken and a guest virtual address is written into mtval, GVA is set. When a trap is taken and a guest virtual address is written into mtval, GVA is cleared.
Type

RW-H	Read-Write with Hardware update Field is writable by software. Any value that fits in the field is acceptable. Hardware also updates the field without an explicit software write.

Reset value: 0

`MBE`

Location: mstatush[5]
Description: see mstatus.MBE
Type

RO	Read-Only Field has a hardwired value that does not change. Writes to an RO field are ignored.

Reset value: 0

`SBE`

Location: mstatush[4]
Description: see mstatus.SBE
Type

RO	Read-Only Field has a hardwired value that does not change. Writes to an RO field are ignored.

Reset value: 0