Datasheet

Datasheet, Volume 2 227
Processor Configuration Registers
30 WO 0b Uncore
Set Root Table Pointer (SRTP)
Software sets this field to set/update the root-entry table pointer
used by hardware. The root-entry table pointer is specified through
the Root-entry Table Address (RTA_REG) register.
Hardware reports the status of the "Set Root Table Pointer"
operation through the RTPS field in the Global Status register.
The "Set Root Table Pointer" operation must be performed before
enabling or re-enabling (after disabling) DMA remapping through
the TE field.
After a "Set Root Table Pointer" operation, software must globally
invalidate the context cache and then globally invalidate of IOTLB.
This is required to ensure hardware uses only the remapping
structures referenced by the new root table pointer, and not stale
cached entries.
While DMA remapping hardware is active, software may update the
root table pointer through this field. However, to ensure valid in-
flight DMA requests are deterministically remapped, software must
ensure that the structures referenced by the new root table pointer
are programmed to provide the same remapping results as the
structures referenced by the previous root-table pointer.
Clearing this bit has no effect. The value returned on read of this
field is undefined.
29 RO 0b Uncore
Set Fault Log (SFL)
This field is valid only for implementations supporting advanced
fault logging.
Software sets this field to request hardware to set/update the
fault-log pointer used by hardware. The fault-log pointer is
specified through Advanced Fault Log register.
Hardware reports the status of the 'Set Fault Log' operation
through the FLS field in the Global Status register.
The fault log pointer must be set before enabling advanced fault
logging (through EAFL field). Once advanced fault logging is
enabled, the fault log pointer may be updated through this field
while DMA remapping is active.
Clearing this bit has no effect. The value returned on read of this
field is undefined.
28 RO 0b Uncore
Enable Advanced Fault Logging (EAFL)
This field is valid only for implementations supporting advanced
fault logging.
Software writes to this field to request hardware to enable or
disable advanced fault logging:
0 = Disable advanced fault logging. In this case, translation faults
are reported through the Fault Recording registers.
1 = Enable use of memory-resident fault log. When enabled,
translation faults are recorded in the memory-resident log.
The fault log pointer must be set in hardware (through the
SFL field) before enabling advanced fault logging. Hardware
reports the status of the advanced fault logging enable
operation through the AFLS field in the Global Status register.
The value returned on a read of this field is undefined.
B/D/F/Type: 0/0/0/GFXVTBAR
Address Offset: 18–1Bh
Reset Value: 0000_0000h
Access: RO, WO
Size: 32 bits
BIOS Optimal Default 000000h
Bit Attr
Reset
Value
RST/
PWR
Description