hideleg

Hypervisor Interrupt Delegation Register

Register hideleg is an HSXLEN-bit read/write register. By default, all traps at any privilege level are handled in M-mode, though M-mode usually uses the medeleg and mideleg CSRs to delegate some traps to HS-mode. The hedeleg and hideleg CSRs allow these traps to be further delegated to a VS-mode guest; their layout is the same as medeleg and mideleg. An interrupt that has been delegated to HS-mode (using mideleg) is further delegated to VS-mode if the corresponding hideleg bit is set. Among bits 15:0 of hideleg, bits 10, 6, and 2 (corresponding to the standard VS-level interrupts) are writable, and bits 12, 9, 5, and 1 (corresponding to the standard S-level interrupts) are read-only zeros.

Attributes

CSR Address	0x603
Defining extension	H
Length	64-bit
Privilege Mode	S

CSR Address

0x603

Defining extension

Length

64-bit

Privilege Mode

Format

Figure 1. hideleg format

Field Summary

Name Location Type Reset Value

Name	Location	Type	Reset Value
`SSI`	1	RO	0
`VSSI`	2	RW	UNDEFINED_LEGAL
`STI`	5	RO	0
`VSTI`	6	RW	UNDEFINED_LEGAL
`SEI`	9	RO	0
`VSEI`	10	RW	UNDEFINED_LEGAL
`SGEI`	12	RO	0
`LCOFI`	13	RW	UNDEFINED_LEGAL

SSI

VSSI

UNDEFINED_LEGAL

STI

VSTI

UNDEFINED_LEGAL

SEI

VSEI

UNDEFINED_LEGAL

SGEI

LCOFI

UNDEFINED_LEGAL

Fields

`SSI`

Location: hideleg[1]
Description: Supervisor Software Interrupt
Type

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

Reset value: 0

`VSSI`

Location: hideleg[2]
Description: Virtual Supervisor Software Interrupt
Type

RW	Read-Write Field is writable by software. Any value that fits in the field is acceptable and shall be retained for subsequent reads.

Reset value

UNDEFINED_LEGAL

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 (csr_value.VSSI == 0) {
  CSR[vsip].SSIP = 0;
  CSR[vsie].SSIE = 0;
}
return csr_value.VSSI;

`STI`

Location: hideleg[5]
Description: Supervisor Timer Interrupt
Type

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

Reset value: 0

`VSTI`

Location: hideleg[6]
Description: Virtual Supervisor Timer Interrupt
Type

RW	Read-Write Field is writable by software. Any value that fits in the field is acceptable and shall be retained for subsequent reads.

Reset value

UNDEFINED_LEGAL

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 (csr_value.VSTI == 0) {
  CSR[vsip].STIP = 0;
  CSR[vsie].STIE = 0;
}
return csr_value.VSTI;

`SEI`

Location: hideleg[9]
Description: Supervisor External Interrupt
Type

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

Reset value: 0

`VSEI`

Location: hideleg[10]
Description: Virtual Supervisor External Interrupt
Type

RW	Read-Write Field is writable by software. Any value that fits in the field is acceptable and shall be retained for subsequent reads.

Reset value

UNDEFINED_LEGAL

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 (csr_value.VSEI == 0) {
  CSR[vsip].SEIP = 0;
  CSR[vsie].SEIE = 0;
}
return csr_value.VSEI;

`SGEI`

Location: hideleg[12]
Description: Supervisor Guest External Interrupt
Type

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

Reset value: 0

`LCOFI`

Location: hideleg[13]
Description: Local-Counter-Overfloat Interrupt
Type

RW	Read-Write Field is writable by software. Any value that fits in the field is acceptable and shall be retained for subsequent reads.

Reset value

UNDEFINED_LEGAL

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 (CSR[mideleg].LCOFI == 0) {
  return 0;
}
if (csr_value.LCOFI == 0) {
  CSR[vsip].LCOFIP = 0;
  CSR[vsie].LCOFIE = 0;
}
return csr_value.LCOFI;

Software read

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

Pruned
Original

XReg mask = 1'1;
return $bits(CSR[CSR[hideleg]]) & 64'1;

XReg mask = CSR[mideleg].VSSI | CSR[mideleg].VSTI | CSR[mideleg].VSEI | CSR[mideleg].LCOFI;
return $bits(CSR[CSR[hideleg]]) & mask;