Advanced Configuration and Power Interface Specification

Advanced Configuration and Power Interface Specification
Device(EC0) {
Name(REGC,Ones)
Method(_REG,2) {
If(Lequal(Arg0, 3)) {
Store(Arg1, REGC)
}
}
}
Method(ECAV,0) {
If(Lequal(REGC,Ones)) {
If(LgreaterEqual(_REV,2)) {
Return(One)
}
Else {
Return(Zero)
}
}
Else {
Return(REGC)
}
}
To detect the availability of the region, call the ECAV method. For example:
If (\_SB.PCI0.EC0.ECAV()) {
...regions are available...
}
else {
...regions are not available...
}
5.2.16 System Resource Affinity Table (SRAT)
This optional table provides information that allows OSPM to associate processors and memory
ranges, including ranges of memory provided by hot-added memory devices, with system localities /
proximity domains and clock domains. On NUMA platforms, SRAT information enables OSPM to
optimally configure the operating system during a point in OS initialization when evaluation of
objects in the ACPI Namespace is not yet possible. OSPM evaluates the SRAT only during OS
initialization. The Local APIC ID / Local SAPIC ID / Local x2APIC ID or the GICC ACPI
Processor UID of all processors started at boot time must be present in the SRAT. If the Local APIC
ID / Local SAPIC ID / Local x2APIC ID or the GICC ACPI Processor UID of a dynamically added
processor is not present in the SRAT, a _PXM object must exist for the processor’s device or one of
its ancestors in the ACPI Namespace.
Table 5-70 Static Resource Affinity Table Format
Field
Byte
Length
Byte
Offset
Description
Header
Signature 4 0 ‘SRAT’. Signature for the System Resource Affinity Table.
Length 4 4 Length, in bytes, of the entire SRAT. The length implies the
number of Entry fields at the end of the table
Revision 1 8 3
Checksum 1 9 Entire table must sum to zero.
158 April, 2015 Version 6.0