instreth

Instructions retired counter, high bits

Alias for high bits of M-mode CSR minstret[63:32].

Privilege mode access is controlled with mcounteren.IR, scounteren.IR, and hcounteren.IR as follows:

mcounteren.IR

scounteren.IR

hcounteren.IR

instret behavior

S-mode

U-mode

VS-mode

VU-mode

0

-

-

IllegalInstruction

IllegalInstruction

IllegalInstruction

IllegalInstruction

1

0

0

read-only

IllegalInstruction

VirtualInstruction

VirtualInstruction

1

1

0

read-only

read-only

VirtualInstruction

VirtualInstruction

1

0

1

read-only

IllegalInstruction

read-only

VirtualInstruction

1

1

1

read-only

read-only

read-only

read-only

Attributes

CSR Address

0xc82

Defining extension

  • Zicntr, version >= Zicntr@2.0.0

Length

32-bit

Privilege Mode

U

Format

instreth format
Figure 1. instreth format

Field Summary

Name Location Type Reset Value

COUNT

31:0

RO-H

UNDEFINED_LEGAL

Fields

COUNT

Location

instreth[31:0]

Description

Alias of minstret.COUNT[63:32].

Type

RO-H

Read-Only with Hardware update

Writes are ignored. Reads reflect a value dynamically generated by hardware.
Reset value

UNDEFINED_LEGAL

Software read

This CSR may return a value that is different from what is stored in hardware.

  • Pruned

  • Original

if (%%LINK%func;mode;mode%%() == PrivilegeMode::S) {
  if (%%LINK%csr_field;mcounteren.IR;CSR[mcounteren].IR%% == 1'b0) {
    %%LINK%func;raise;raise%%(ExceptionCode::IllegalInstruction, %%LINK%func;mode;mode%%(), $encoding);
  }
} else if (%%LINK%func;mode;mode%%() == PrivilegeMode::U) {
  if (%%LINK%csr_field;misa.S;CSR[misa].S%% == 1'b1) {
    if ((%%LINK%csr_field;mcounteren.IR;CSR[mcounteren].IR%% & %%LINK%csr_field;scounteren.IR;CSR[scounteren].IR%%) == 1'b0) {
      %%LINK%func;raise;raise%%(ExceptionCode::IllegalInstruction, %%LINK%func;mode;mode%%(), $encoding);
    }
  } else if (%%LINK%csr_field;mcounteren.IR;CSR[mcounteren].IR%% == 1'b0) {
    %%LINK%func;raise;raise%%(ExceptionCode::IllegalInstruction, %%LINK%func;mode;mode%%(), $encoding);
  }
} else if (%%LINK%func;mode;mode%%() == PrivilegeMode::VS) {
  if (%%LINK%csr_field;hcounteren.IR;CSR[hcounteren].IR%% == 1'b0 && %%LINK%csr_field;mcounteren.IR;CSR[mcounteren].IR%% == 1'b1) {
    %%LINK%func;raise;raise%%(ExceptionCode::VirtualInstruction, %%LINK%func;mode;mode%%(), $encoding);
  } else if (%%LINK%csr_field;mcounteren.IR;CSR[mcounteren].IR%% == 1'b0) {
    %%LINK%func;raise;raise%%(ExceptionCode::IllegalInstruction, %%LINK%func;mode;mode%%(), $encoding);
  }
} else if (%%LINK%func;mode;mode%%() == PrivilegeMode::VU) {
  if (%%LINK%csr_field;hcounteren.IR;CSR[hcounteren].IR%% & %%LINK%csr_field;scounteren.IR;CSR[scounteren].IR%%) == 1'b0) && (%%LINK%csr_field;mcounteren.IR;CSR[mcounteren].IR%% == 1'b1 {
    %%LINK%func;raise;raise%%(ExceptionCode::VirtualInstruction, %%LINK%func;mode;mode%%(), $encoding);
  } else if (%%LINK%csr_field;mcounteren.IR;CSR[mcounteren].IR%% == 1'b0) {
    %%LINK%func;raise;raise%%(ExceptionCode::IllegalInstruction, %%LINK%func;mode;mode%%(), $encoding);
  }
}
return %%LINK%func;read_mcycle;read_mcycle%%();
if (%%LINK%func;mode;mode%%() == PrivilegeMode::S) {
  if (%%LINK%csr_field;mcounteren.IR;CSR[mcounteren].IR%% == 1'b0) {
    %%LINK%func;raise;raise%%(ExceptionCode::IllegalInstruction, %%LINK%func;mode;mode%%(), $encoding);
  }
} else if (%%LINK%func;mode;mode%%() == PrivilegeMode::U) {
  if (%%LINK%csr_field;misa.S;CSR[misa].S%% == 1'b1) {
    if ((%%LINK%csr_field;mcounteren.IR;CSR[mcounteren].IR%% & %%LINK%csr_field;scounteren.IR;CSR[scounteren].IR%%) == 1'b0) {
      %%LINK%func;raise;raise%%(ExceptionCode::IllegalInstruction, %%LINK%func;mode;mode%%(), $encoding);
    }
  } else if (%%LINK%csr_field;mcounteren.IR;CSR[mcounteren].IR%% == 1'b0) {
    %%LINK%func;raise;raise%%(ExceptionCode::IllegalInstruction, %%LINK%func;mode;mode%%(), $encoding);
  }
} else if (%%LINK%func;mode;mode%%() == PrivilegeMode::VS) {
  if (%%LINK%csr_field;hcounteren.IR;CSR[hcounteren].IR%% == 1'b0 && %%LINK%csr_field;mcounteren.IR;CSR[mcounteren].IR%% == 1'b1) {
    %%LINK%func;raise;raise%%(ExceptionCode::VirtualInstruction, %%LINK%func;mode;mode%%(), $encoding);
  } else if (%%LINK%csr_field;mcounteren.IR;CSR[mcounteren].IR%% == 1'b0) {
    %%LINK%func;raise;raise%%(ExceptionCode::IllegalInstruction, %%LINK%func;mode;mode%%(), $encoding);
  }
} else if (%%LINK%func;mode;mode%%() == PrivilegeMode::VU) {
  if (%%LINK%csr_field;hcounteren.IR;CSR[hcounteren].IR%% & %%LINK%csr_field;scounteren.IR;CSR[scounteren].IR%%) == 1'b0) && (%%LINK%csr_field;mcounteren.IR;CSR[mcounteren].IR%% == 1'b1 {
    %%LINK%func;raise;raise%%(ExceptionCode::VirtualInstruction, %%LINK%func;mode;mode%%(), $encoding);
  } else if (%%LINK%csr_field;mcounteren.IR;CSR[mcounteren].IR%% == 1'b0) {
    %%LINK%func;raise;raise%%(ExceptionCode::IllegalInstruction, %%LINK%func;mode;mode%%(), $encoding);
  }
}
return %%LINK%func;read_mcycle;read_mcycle%%();