Advanced Configuration and Power Interface Specification

Advanced Configuration and Power Interface Specification
Reserved 31 1 Must be zero.
5.2.16.2 Memory Affinity Structure
The Memory Affinity structure provides the following topology information statically to the
operating system:
• The association between a range of memory and the proximity domain to which it belongs
• Information about whether the range of memory can be hot-plugged.
Table 5-73 provides the details of the Memory Affinity structure.
Table 5-73 Memory Affinity Structure
Field
Byte
Length
Byte
Offset
Description
Type 1 0 1 Memory Affinity Structure
Length 1 1 40
Proximity Domain 4 2 Integer that represents the proximity domain to which the
processor belongs
Reserved 2 6 Reserved
Base Address Low 4 8 Low 32 Bits of the Base Address of the memory range
Base Address High 4 12 High 32 Bits of the Base Address of the memory range
Length Low 4 16 Low 32 Bits of the length of the memory range.
Length High 4 20 High 32 Bits of the length of the memory range.
Reserved 4 24 Reserved.
Flags 4 28 Flags – Memory Affinity Structure. Indicates whether the region of
memory is enabled and can be hot plugged. See Table 5-74.
Reserved 8 32 Reserved.
Table 5-74 Flags – Memory Affinity Structure
Field
Bit
Length
Bit
Offset
Description
Enabled 1 0 If clear, the OSPM ignores the contents of the Memory Affinity
Structure. This allows system firmware to populate the SRAT with
a static number of structures but only enable then as necessary.
Hot Pluggable 1 1 The information conveyed by this bit depends on the value of the
Enabled bit.
If the Enabled bit is set and the Hot Pluggable bit is also set. The
system hardware supports hot-add and hot-remove of this memory
region
If the Enabled bit is set and the Hot Pluggable bit is clear, the
system hardware does not support hot-add or hot-remove of this
memory region.
If the Enabled bit is clear, the OSPM will ignore the contents of the
Memory Affinity Structure
NonVolatile 1 2 If set, the memory region represents Non-Volatile memory
160 April, 2015 Version 6.0