Advanced Configuration and Power Interface Specification

14.1.3 Generic Communications Subspace Structure (type 0) .................................. 676
14.1.4 HW-Reduced Communications Subspace Structure (type 1) ......................... 677
14.1.5 HW-Reduced Communications Subspace Structure (type 2) ......................... 678
14.2 Generic Communications Channel Shared Memory Region ...................................... 680
14.2.1 Generic Communications Channel Command Field ....................................... 680
14.2.2 Generic Communications Channel Status Field ............................................. 680
14.3 Doorbell Protocol ........................................................................................................ 681
14.4 Platform Notification.................................................................................................... 681
14.5 Referencing the PCC address space.......................................................................... 682
15
System Address Map Interfaces ............................................................... 683
15.1 INT 15H, E820H - Query System Address Map ......................................................... 684
15.2 E820 Assumptions and Limitations............................................................................. 686
15.3 UEFI GetMemoryMap() Boot Services Function......................................................... 687
15.4 UEFI Assumptions and Limitations ............................................................................. 688
15.5 Example Address Map................................................................................................ 688
15.6 Example: Operating System Usage............................................................................ 689
16
Waking and Sleeping ................................................................................. 691
16.1 Sleeping States........................................................................................................... 693
16.1.1 S1 Sleeping State ........................................................................................... 695
16.1.2 S2 Sleeping State ........................................................................................... 696
16.1.3 S3 Sleeping State ........................................................................................... 696
16.1.4 S4 Sleeping State ........................................................................................... 697
16.1.5 S5 Soft Off State ............................................................................................. 698
16.1.6 Transitioning from the Working to the Sleeping State..................................... 699
16.1.7 Transitioning from the Working to the Soft Off State....................................... 700
16.2 Flushing Caches ......................................................................................................... 700
16.3 Initialization ................................................................................................................. 700
16.3.1 Placing the System in ACPI Mode .................................................................. 703
16.3.2 BIOS Initialization of Memory.......................................................................... 703
16.3.3 OS Loading ..................................................................................................... 705
16.3.4 Exiting ACPI Mode .......................................................................................... 707
17
Non-Uniform Memory Access (NUMA) Architecture Platforms ............. 709
17.1 NUMA Node................................................................................................................ 709
17.2 System Locality........................................................................................................... 709
17.2.1 System Resource Affinity Table Definition ...................................................... 710
17.2.2 System Resource Affinity Update ................................................................... 710
17.3 System Locality Distance Information......................................................................... 710
17.3.1 Online Hot Plug ............................................................................................... 711
17.3.2 Impact to Existing Localities............................................................................ 711
Version 6.0
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