The GICH_VTR characteristics are:
Indicates the number of implemented virtual priority bits and List registers.
This register is part of the GIC virtualised guest interface control registers functional group.
This register is accessible as follows:
Security disabled | Secure | Non-secure |
---|---|---|
RO | RO | RO |
This register is used only when System register access is not enabled. When System register access is enabled:
This register is available when the GIC implementation supports interrupt virtualization.
GICH_VTR is a 32-bit register.
The GICH_VTR bit assignments are:
31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
PRIbits | PREbits | IDbits | SEIS | A3V | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | ListRegs |
The number of virtual priority bits implemented, minus one.
An implementation must implement at least 32 levels of virtual priority (5 priority bits).
The number of virtual preemption bits implemented, minus one.
An implementation must implement at least 32 levels of virtual preemption priority (5 preemption bits).
The value of this field must be less than or equal to the value of GICH_VTR.PRIbits.
The number of virtual interrupt identifier bits supported:
IDbits | Meaning |
---|---|
000 |
16 bits. |
001 |
24 bits. |
All other values are reserved.
SEI support. Indicates whether the virtual CPU interface supports generation of SEIs:
SEIS | Meaning |
---|---|
0 |
The virtual CPU interface logic does not support generation of SEIs. |
1 |
The virtual CPU interface logic supports generation of SEIs. |
Affinity 3 valid. Possible values are:
A3V | Meaning |
---|---|
0 |
The virtual CPU interface logic only supports zero values of the Aff3 field in ICC_SGI0R_EL1, ICC_SGI1R_EL1, and ICC_ASGI1R_EL1. |
1 |
The virtual CPU interface logic supports nonzero values of the Aff3 field in ICC_SGI0R_EL1, ICC_SGI1R_EL1, and ICC_ASGI1R_EL1. |
Reserved, RES0.
The number of implemented List registers, minus one.
GICH_VTR can be accessed through its memory-mapped interface:
Component | Offset |
---|---|
GIC Virtual interface control | 0x0004 |
28/09/2017 08:24
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