mhpmevent31

Machine Hardware Performance Counter 31 Control

Programmable hardware performance counter event selector and overflow/filtering control

Attributes

CSR Address	0x33f
Defining extension	Smhpm, version >= 0
Length	64-bit
Privilege Mode	M

CSR Address

0x33f

Defining extension

Smhpm, version >= 0

Length

64-bit

Privilege Mode

Format

Figure 1. mhpmevent31 format

Field Summary

Name	Location	Type
`OF`	63	RO
`MINH`	62	RO
`SINH`	61	RO
`UINH`	60	RO
`VSINH`	59	RO
`VUINH`	58	RO
`EVENT`	57:0	RO

Fields

`OF`

Location: mhpmevent31[63]
Description: Overflow status and interrupt disable.

The OF bit is set when the corresponding hpmcounter overflows, and remains set until written by software. Since hpmcounter values are unsigned values, overflow is defined as unsigned overflow of the implemented counter bits.

The OF bit is sticky; it stays set until explictly cleared by a CSR write.

A Local Counter Overflow Interrupt (LCOFI) is generated when OF is clear and mhpmcounter31 overflows.
Type

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

Reset value: 0

`MINH`

Location: mhpmevent31[62]
Description: When set, mhpmcounter31 does not increment while the hart in operating in M-mode.
Type

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

Reset value: 0

`SINH`

Location: mhpmevent31[61]
Description: When set, mhpmcounter31 does not increment while the hart in operating in (H)S-mode.
Type

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

Reset value: 0

`UINH`

Location: mhpmevent31[60]
Description: When set, mhpmcounter31 does not increment while the hart in operating in U-mode.
Type

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

Reset value: 0

`VSINH`

Location: mhpmevent31[59]
Description: When set, mhpmcounter31 does not increment while the hart in operating in VS-mode.
Type

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

Reset value: 0

`VUINH`

Location: mhpmevent31[58]
Description: When set, mhpmcounter31 does not increment while the hart in operating in VU-mode.
Type

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

Reset value: 0

`EVENT`

Location: mhpmevent31[57:0]
Description: Event selector for performance counter mhpmcounter31.
Type

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

Reset value

Software write

This field has special behavior when written by software (e.g., through csrrw).

When software tries to write csr_value, the field will be written with the return value of the function below.

if (ary_includes?<$array_size(HPM_EVENTS), 58>(HPM_EVENTS, csr_value.EVENT)) {
  return csr_value.EVENT;
} else {
  return UNDEFINED_LEGAL_DETERMINISTIC;
}