Advanced Configuration and Power Interface Specification

ACPI-Defined Devices and Device-Specific Objects
0x00000000 – Succeeded to set all memory bandwidth monitoring parameters.
Non-Zero – At least one memory bandwith monitoring parameter value could not be set as
follows:
Table 9-262 MSM Result Encoding
Bits Definition
0 If clear indicates WindowSize was set successfully. If set, indicates invalid WindowSize
argument.
1 If clear indicates SamplingInterval was set successfully. If set, indicates invalid
SamplingInterval argument.
2 If clear indicates LowNotificationThreshold was set successfully. If set, indicates invalid
LowNotificationThreshold argument.
3 If clear indicates HighNotificationThreshold was set successfully. If set, indicates invalid
HighNotificationThreshold argument.
31:4 Reserved (must be 0)
9.12.3 _OSC Definition for Memory Device
OSPM evaluates _OSC under the Memory Device to convey OSPM capabilities to the platform.
Argument definitions are as follows:
Arguments: (4)
Arg0 – UUID (Buffer): 03B19910-F473-11DD-87AF-0800200C9A66
Arg1 – Revision ID (Integer): 1
Arg2 – Count of Entries in Arg3 (Integer): 2
Arg3 – DWORD capabilities (Buffer): First DWORD: as described in Section 6.2.10, Second
DWORD: See Table 6-210.
Return Value:
A Buffer containing platform capabilities
Table 9-263 Memory Device _OSC Capabilities DWORD number 2
Bits Field Name Definition
0 Memory
Bandwidth
Change
Notifications
31:1 Reserved (must be 0)
This bit is set if OSPM supports the processing of memory bandwidth change
notifications. If the platform supports the ability to issue a notification when
Memory Bandwidth changes, it may only do so after _OSC has been evaluated
with this bit set. _OSC evaluation with this bit clear will cause the platform to
cease issuing notifications if previously enabled.
Return Value Information
Capabilities Buffer (Buffer) – The platform acknowledges the Capabilities Buffer by returning a
buffer of DWORDs of the same length. Set bits indicate acknowledgement and cleared bits
indicate that the platform does not support the capability.
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