Intel® Core™ Ultra 200V Series Processors SOC I/O Registers
| ID | Date | Version | Classification |
|---|---|---|---|
| 831520 | 09/03/2024 | 001 | Public |
IOTLB Invalidate Register (IOTLB_REG_0_0_0_VTDBAR) – Offset 20ef8
Register to invalidate IOTLB. The act of writing the upper byte of the IOTLB_REG with IVT field Set causes the hardware to perform the IOTLB invalidation.
| Bit Range | Default | Access | Field Name and Description |
|---|---|---|---|
| 63 | 0h | RW/V | Invalidate IOTLB (IVT) Software requests IOTLB invalidation by setting this field. Software must also set the requested invalidation granularity by programming the IIRG field Hardware clears the IVT field to indicate the invalidation request is complete. Hardware also indicates the granularity at which the invalidation operation was performed through the IAIG field. Software must not submit another invalidation request through this register while the IVT field is Set, nor update the associated Invalidate Address register Software must not submit IOTLB invalidation requests when there is a context-cache invalidation request pending at this remapping hardware unit. Hardware implementations reporting write-buffer flushing requirement (RWBF=1 in Capability register) must implicitly perform a write buffer flushing before invalidating the IOTLB. |
| 62 | 0h | RO | Reserved |
| 61:60 | 0h | RW | IOTLB Invalidation Request Granularity (IIRG) When requesting hardware to invalidate the IOTLB (by setting the IVT field), software writes the requested invalidation granularity through this field. The following are the encodings for the field
Hardware implementations may process an invalidation request by performing invalidation at a coarser granularity than requested. Hardware indicates completion of the invalidation request by clearing the IVT field. At this time, the granularity at which actual invalidation was performed is reported through the IAIG field |
| 59 | 0h | RO | Reserved |
| 58:57 | 1h | RO/V | IOTLB Actual Invalidation Granularity (IAIG) Hardware reports the granularity at which an invalidation request was processed through this field when reporting invalidation completion (by clearing the IVT field). The following are the encodings for this field
|
| 56:50 | 0h | RO | Reserved |
| 49 | 0h | RW | Drain Reads (DR) This field is ignored by hardware if the DRD field is reported as clear in the Capability register. When the DRD field is reported as Set in the Capability register, the following encodings are supported for this field:
|
| 48 | 0h | RW | Drain Writes (DW) This field is ignored by hardware if the DWD field is reported as Clear in the Capability register. When the DWD field is reported as Set in the Capability register, the following encodings are supported for this field:
|
| 47:32 | 0h | RW | Domain-ID (DID) Indicates the ID of the domain whose IOTLB entries need to be selectively invalidated. This field must be programmed by software for domain-selective and page-selective invalidation requests. The Capability register reports the domain-id width supported by hardware. Software must ensure that the value written to this field is within this limit. Hardware ignores and not implements bits 47:(32+N), where N is the supported domain-id width reported in the Capability register. |
| 31:0 | 0h | RO | Reserved |