Case Study: ATI Device Case Study: ATI Device Power Management In Power Management In Windows VistaWindows Vista

Phil MummahPhil MummahSoftware ArchitectSoftware ArchitectATIATI

AgendaAgenda

Device power managementDevice power managementOverviewOverview

ATI PowerPlayATI PowerPlayTMTM technology technology

Integrating with Windows Vista Power ManagerIntegrating with Windows Vista Power ManagerWindows Vista enhancementsWindows Vista enhancements

Implementation detailsImplementation details

DemoDemo

SummarySummary

Additional resourcesAdditional resources

Power ManagementPower ManagementOverviewOverview

Device Run time idle detectionDevice Run time idle detectionTransition an inactive device into a low power, non-working power state Transition an inactive device into a low power, non-working power state (e.g., D2)(e.g., D2)

Wake and transition to D0 on I/O traffic, interruptWake and transition to D0 on I/O traffic, interrupt

Device-specific tradeoff of performance for reduced Device-specific tradeoff of performance for reduced power consumptionpower consumption

In the context of the device’s On state (D0)In the context of the device’s On state (D0)Examples: scale device clock rates and core voltages, clock gating,Examples: scale device clock rates and core voltages, clock gating,vary transmit power or communication speed, etc.vary transmit power or communication speed, etc.

Device performance statesDevice performance statesAnalogous to ACPI processor performance statesAnalogous to ACPI processor performance states

Discrete combinations of power consumption and performance Discrete combinations of power consumption and performance

Application performance tradeoff for reduced powerApplication performance tradeoff for reduced powerReduce unnecessary activity in battery modeReduce unnecessary activity in battery mode

Device Power ManagementDevice Power ManagementOpportunities and goalsOpportunities and goals

Extend mobile PC battery lifeExtend mobile PC battery lifeCustomers want extended battery life and Customers want extended battery life and are willing to pay for itare willing to pay for it

Differentiate your products Differentiate your products Add significant value to your deviceAdd significant value to your device

Drive down system power consumptionDrive down system power consumptionReduce fan noise, system thermal outputReduce fan noise, system thermal output

Equally applicable to mobile and Equally applicable to mobile and desktop systemsdesktop systems

Device Power ManagementDevice Power ManagementOpportunities and goalsOpportunities and goals

Devices, services and applications all help Devices, services and applications all help to reduce system power consumptionto reduce system power consumption

WattsWatts

55

1010

1515

20202525

3030

3535

4040

Max CPUMax CPUMax LCDMax LCD

Max AnimationMax Animation

Min LCDMin LCD

MinMinAnimationAnimation

Min CPUMin CPUMax LCDMax LCD

Max AnimationMax Animation

Min LCDMin LCD

MinMinAnimationAnimation

Device Power ManagementDevice Power ManagementATI PowerPlayATI PowerPlay

Reduces the power consumption of ATI Mobile Reduces the power consumption of ATI Mobile RadeonTM graphics devicesRadeonTM graphics devices

When the device is idleWhen the device is idle

When the system is running on batteryWhen the system is running on battery

Exposes API for OEM enhancementsExposes API for OEM enhancements

Offers users the optimal balance of performance Offers users the optimal balance of performance and power consumptionand power consumption

ATI PowerPlayTM drives continuingATI PowerPlayTM drives continuinginnovation and advancement in graphicsinnovation and advancement in graphicspower managementpower management

Integrated with Windows Vista power managementIntegrated with Windows Vista power management

Device Power ManagementDevice Power ManagementATI PowerPlayATI PowerPlay

PowerPlay capabilitiesPowerPlay capabilitiesGPU core voltage and frequency scalingGPU core voltage and frequency scaling

Memory clock scalingMemory clock scaling

Refresh rate reductionRefresh rate reduction

PCI Express dynamic lane width switchingPCI Express dynamic lane width switching

Thermal throttlingThermal throttling

……and moreand more

Windows Vista Power PolicyWindows Vista Power PolicyBenefits of integrationBenefits of integration

Offers users a seamless power Offers users a seamless power management experiencemanagement experience

Provide unified power management controlsProvide unified power management controls

Allows the entire platform to respond to the Allows the entire platform to respond to the user’s current power policyuser’s current power policy

Devices automatically respond to Devices automatically respond to changing system conditionschanging system conditions

Active power scheme/personalityActive power scheme/personality

AC/DC power source changes AC/DC power source changes

Windows Vista Power PolicyWindows Vista Power PolicyEnhancementsEnhancements

Extensible power setting storeExtensible power setting storeDevices or applications can define and install custom Devices or applications can define and install custom power settingspower settingsWindows power manager stores setting data, friendly Windows power manager stores setting data, friendly names, values, etc.names, values, etc.

All power settings appear in Windows All power settings appear in Windows Power OptionsPower Options

Including custom third-party power settingsIncluding custom third-party power settingsNo need to provide additional configuration UINo need to provide additional configuration UI

Robust command-line tool for Robust command-line tool for system administratorsystem administrator

Makes testing, debugging easierMakes testing, debugging easier

Windows Vista Power PolicyWindows Vista Power PolicyUser experience improvementsUser experience improvements

Simplified power plansSimplified power plansThree default power plansThree default power plans

Power Saver, Automatic, High PerformancePower Saver, Automatic, High Performance

Indicates the overall power management Indicates the overall power management policy to the systempolicy to the system

Each plans has a personality settingEach plans has a personality setting

Users can easily change the active Users can easily change the active power planspower plans

One-click from the desktop with the One-click from the desktop with the battery meterbattery meter

Windows Vista Power PolicyWindows Vista Power PolicySteps to driver integrationSteps to driver integration

Define custom power policy settingsDefine custom power policy settings

Install custom power settingsInstall custom power settings

Prepare the device driver toPrepare the device driver toRegister for power events of interestRegister for power events of interest

Respond appropriately to these events Respond appropriately to these events

Optionally, provide additional power Optionally, provide additional power management UImanagement UI

Implementation DetailsImplementation DetailsDefining a power settingDefining a power setting

A custom power setting definition containsA custom power setting definition containsA GUID uniquely identifying the settingA GUID uniquely identifying the setting

Friendly name, description stringsFriendly name, description strings

One or more setting valuesOne or more setting valuesRange, e.g.,Range, e.g.,

0 – 100%0 – 100%

Value: 10 minutesValue: 10 minutes

Discrete valuesDiscrete valuesE.g., {Enabled, Disabled}; {High, Medium, Low}E.g., {Enabled, Disabled}; {High, Medium, Low}

Implementation DetailsImplementation DetailsDefining a power settingDefining a power setting

Critical step:Critical step: Define appropriate defaults Define appropriate defaultsEach power scheme personality’s defaultsEach power scheme personality’s defaults

Users might not change the power policy for your Users might not change the power policy for your power settingpower setting

System power source (AC/DC)System power source (AC/DC)

Each device can define multiple Each device can define multiple power settingspower settings

Power settings can be placed in subgroupsPower settings can be placed in subgroups

Implementation DetailsImplementation DetailsExample: Defining a power settingExample: Defining a power setting

GUIDGUID{191F65B5-D45C-4a4f-8AAE-1AB8BFD980E6}{191F65B5-D45C-4a4f-8AAE-1AB8BFD980E6}

Friendly NameFriendly Name““ATI Graphics Engine PowerPlay”ATI Graphics Engine PowerPlay”

DescriptionDescription““Configures the GPU Power Management Mode”Configures the GPU Power Management Mode”

Values (discrete)Values (discrete)ATI Max Performance ModeATI Max Performance Mode

ATI Balanced ModeATI Balanced Mode

ATI Max Battery ModeATI Max Battery Mode

SubgroupSubgroupNew subgroup created for all ATI PowerPlay settingsNew subgroup created for all ATI PowerPlay settings

Implementation DetailsImplementation DetailsInstalling a power settingInstalling a power setting

Add the setting and its definition to the power Add the setting and its definition to the power policy storepolicy store

Two methods supportedTwo methods supportedINF-based installationINF-based installation

Ideal for device driversIdeal for device drivers

New INF directives for describing power setting,New INF directives for describing power setting,subgroup, possible valuessubgroup, possible values

Multiple settings can be described in the same INF fileMultiple settings can be described in the same INF file

API-based installationAPI-based installationWin32 APIs in Power Profiles Library (powrprof.dll)Win32 APIs in Power Profiles Library (powrprof.dll)

[DeviceName]AddPowerSetting=AtiPowerPolicy

[AtiPowerPolicy]Subgroup = {2566CF20-D01A-456f-BFE1-C6C6E76D15A6}, "ATI Graphics Main Power Settings", "Set all graphics power settings "

Setting = {191F65B5-D45C-4a4f-8AAE-1AB8BFD980E6},{191F65B5-D45C-4a4f-8AAE-1AB8BFD980E6}, “ATI Graphics Engine PowerPlay Settings”, “Configures the GPU Power Management Mode”

Value=0, "Max Battery Mode", "Minimum Power Setting", REG_DWORD, <0>Value=1, "Balanced Mode", "Medium Power Setting", REG_DWORD, <1>Value=2, "Max Performance Mode", "Max Power Setting", REG_DWORD, <2>

Default = %GUID_MAX_POWER_SAVINGS%, %AC%, 1Default = %GUID_MAX_POWER_SAVINGS%, %DC%, 0Default = %GUID_TYPICAL_POWER_SAVINGS%, %AC%, 2Default = %GUID_TYPICAL_POWER_SAVINGS%, %DC%, 0Default = %GUID_MIN_POWER_SAVINGS%, %AC%, 2Default = %GUID_MIN_POWER_SAVINGS%, %DC%, 1

Range of Values can also be done, ie 0 – 100%

Implementation DetailsImplementation DetailsExample: Installing a power settingExample: Installing a power setting

Setting Friendly Name, Description

Power Setting Defined By GUID

Discrete List of Values

Default Values for EachPower Scheme Personality

Implementation DetailsImplementation DetailsRegister for notificationsRegister for notifications

Register within device or application Register within device or application initialization codeinitialization code

PoRegisterPowerSettingNotification()

Register with custom power setting GUIDRegister with custom power setting GUID

De-register when your device is stoppedDe-register when your device is stopped

Kernel-mode registration function includes Kernel-mode registration function includes context parameter context parameter

Most drivers will pass device extension in contextMost drivers will pass device extension in context

Enables drivers to handle registration for Enables drivers to handle registration for multiple devicesmultiple devices

KRSContext::RegisterPowerSettingCallback( IN PDEVICE_OBJECT DeviceObject, OUT HANDLE PowerSettingCallbackHandle ) { NTSTATUS Status = STATUS_SUCCESS;

Status = PoRegisterPowerSettingCallbackPoRegisterPowerSettingCallback(DeviceObject,

(LPGUID)(&GUID_GRAPHICS_ENGINE_POWER_PLAY_MODE),(PPOWER_SETTING_CALLBACK)&PowerSettingCallback,&PowerSettingCallback,

DeviceObject->DeviceObjectExtension,

&PowerSettingCallbackHandle );

return Status;}

Power Setting GUID

De-register WhenDevice is Stopped

Implementation DetailsImplementation DetailsExample: Register for notificationsExample: Register for notifications

NTSTATUSPowerSettingCallbackPowerSettingCallback( IN CONST LPGUID SettingGuid, IN PULONG NewValue, IN ULONG ValueLength, IN PVOID Context ) { NTSTATUS Status = STATUS_INVALID_PARAMETER;

// Check for correct GUID, Dataif (IsEqualGUID(

(LPGUID)(&GUID_GRAPHICS_ENGINE_POWER_PLAY_MODEGUID_GRAPHICS_ENGINE_POWER_PLAY_MODE),SettingGUID ) &&(ValueLength == sizeof(DWORD)) &&(NewValue != NULL) )

{// NOT SHOWN: Any necessary locks

// Change graphics engine power mode// Change graphics engine power mode }

return Status;}

Power Setting GUID

Change the Device PowerManagement Behavior

Implementation DetailsImplementation DetailsExample: Driver callback functionExample: Driver callback function

NTSTATUSUnRegisterPowerSettingCallback( IN HANDLE PowerSettingCallbackHandle ) { NTSTATUS Status = STATUS_SUCCESS; Status = PoUnRegisterPowerSettingCallbackPoUnRegisterPowerSettingCallback(

&PowerSettingCallbackHandle);

return Status;}

Implementation DetailsImplementation DetailsExample: Deregister for notificationsExample: Deregister for notifications

Note:Power settings

may besystem-specific

Implementation DetailsImplementation DetailsPower configuration user interfacePower configuration user interface

Default powersettings

UI extended with custom

power settings

Implementation DetailsImplementation DetailsPower configuration user interfacePower configuration user interface

Implementation DetailsImplementation DetailsUser interface summaryUser interface summary

Windows automatically Windows automatically adds custom power adds custom power settings to Power Options settings to Power Options Advanced Settings UIAdvanced Settings UI

Multiple settingsMultiple settingscan be containedcan be containedin a new subgroupin a new subgroup

Each setting hasEach setting hasan AC and DC valuean AC and DC value

Settings can beSettings can bediscrete or range discrete or range of valuesof values

UI extended with additionalproperty sheet

Implementation DetailsImplementation DetailsPower configuration user interfacePower configuration user interface

Implementation DetailsImplementation DetailsUser interface summaryUser interface summary

Property sheets mayProperty sheets maybe added for more be added for more advanced UIadvanced UI

May have a supersetMay have a supersetof functionalityof functionality

E.g., battery E.g., battery degrade behaviorsdegrade behaviors

Property sheetsProperty sheetscan leverage Powercan leverage PowerPolicy APIsPolicy APIs

ATI exposes PowerPlay ATI exposes PowerPlay functionality functionality

OEM does notOEM does notneed to write specialneed to write specialUI to add featuresUI to add features

Integrating PowerPlay Integrating PowerPlay With Windows VistaWith Windows Vista

Phil MummahPhil MummahSW ArchitectSW ArchitectATIATI

Call To ActionCall To Action

Implement device power management Implement device power management technologies in your hardware designstechnologies in your hardware designs

Take advantage of Windows Vista power Take advantage of Windows Vista power management integration opportunitiesmanagement integration opportunities

Review Integrating with Windows Vista Review Integrating with Windows Vista Power Policy white paperPower Policy white paper

http://http://go.microsoft.com/fwlink/?LinkIdgo.microsoft.com/fwlink/?LinkId=51286=51286

Additional ResourcesAdditional Resources

ATI Technologies, Inc.ATI Technologies, Inc.http://www.ati.comhttp://www.ati.com

ATI PowerPlayTM white paperATI PowerPlayTM white paperhttp://www.ati.com/products/pdf/powerplaywp2.pdf http://www.ati.com/products/pdf/powerplaywp2.pdf

Windows Hardware and Driver CentralWindows Hardware and Driver Centralhttp://www.microsoft.com/whdchttp://www.microsoft.com/whdc

Power Management, ACPI on WHDCPower Management, ACPI on WHDChttp://www.microsoft.com/whdc/system/pnppwr/powermgmt/http://www.microsoft.com/whdc/system/pnppwr/powermgmt/default.mspxdefault.mspx

Integrating with Windows Vista Power Policy Integrating with Windows Vista Power Policy white paperwhite paper

http://go.microsoft.com/fwlink/?LinkId=51286http://go.microsoft.com/fwlink/?LinkId=51286

© 2006 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions,

it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.