ACS-2 Extended Power Conditions (EPC) June 10, 2008 Revision 0 Technical Editor: Jim Hatfield 389 Disc Drive Longmont, CO 80503 USA 720-684-2120 James.C.Hatfield@seagate.com 06/10/2008 Page 1 of 24
Document Status Revision History (part 1 of 1) Rev Date 0 June 10, 2008 1) Initial Revision 1 Introduction This proposal is an attempt to standardize fine grained power management controls. The industry currently has some vendor specific methods. 2 Scope This is intended for incorporation into ACS-2. 3 Overview This adds substates (power conditions) to the PM1: Idle power management state, and methods to use and configure their use. 4 Changes to ACS-2 4.1 Changes to clause 2 (No changes) 4.2 Changes to clause 3 (No changes) 4.3 Changes to clause 4 4.3.1 Overview - Changes to the Feature Set Summary Table Add: Extended Power Conditions (EPC) to the table as Optional for ATA and Prohibited for ATAPI 4.3.2 Security Mode feature fet - Changes to the Security Mode Command Actions Table (No changes) 4.3.3 Long Logical Sector feature set - Block Size By Command Table (No changes) 4.3.4 (new) Extended Power Conditions (EPC) feature set The Extended Power Conditions feature set provides a host with additional methods to control the power condition of a device. These methods include: a) defining some power conditions within the PM1: Idle power management state: Idle1, Idle2 and Idle3. b) specifying that the device transition to a power condition without delay; and c) enabling and initializing any of the power condition timers to specify that the device wait for a period of inactivity before transitioning to a specified power condition; and 06/10/2008 Page 2 of 24
d) allowing the host to determine the power condition parameters of the device. The following command-related device properties are mandatory if this feature set is supported: a) the SET FEATURES Extended Power Conditions subcommand b) the Power Conditions log page c) extensions to the CHECK POWER MODE command d) IDENTIFY DEVICE fields e) DCO controls 4.3.4.1 Interaction with other features and resets The Extended Power Conditions feature set may be used concurrently with the normal APM feature set. Devices that contain cache memory shall write all cached data to the medium for the device (e.g., as a device does in response to a flush command) prior to entering into any power condition that prevents accessing the media (e.g., before a hard drive stops its spindle motor during transition to the standby power condition). Timer values and properties shall be preserved across all resets. The EPC timers shall be disabled after a power-on reset and may be enabled using the SET FEATURES Extended Power Conditions subcommand. Enabled EPC timers shall remain enabled across all other resets. 4.3.4.2 Power conditions The Idle1, Idle2 and Idle3 power conditions are within the PM1: Idle power management state. The power conditions shall be ordered from least power savings (and shortest recovery time) to most power savings (and longest recovery time) as follows: Idle1, Idle2, Idle3 and PM2:Standby. Each of these power conditions may be associated with an individual timer, power-on defaults and additional properties information. 4.3.4.3 Power condition timers The device may have power-on default settings for the power condition timers. Power condition timers are changeable with the SET FEATURES Extended Power Conditions subcommand (see xxx). Configured settings for the timers shall be readable in the device statistics Power Conditions log page (see xxx). A power condition timer set to zero indicates that the associated power condition is disabled. The value of each timer specifies the inactivity time in 100 millisecond increments that the device shall wait before transitioning to the idle power condition when the associated bit is set to one. All enabled power condition timers are active and run concurrently. When a device receives a command while in a power condition based on a setting in the Extended Power Conditions feature set, the device shall transition to the PM0:Active power management state. If any power condition timer has been enabled, then they shall be halted on receipt of the command. On completion of the command, the enabled timer(s) shall be initialized and started. A power condition timer expires when the time specified by the value in the timer field times 100 milliseconds has elapsed since the last activity completed (e.g., processing a command that requires the PM0:Active power condition or performing a self test). When an enabled timer expires, the device shall transition to the power condition associated with that timer. Timer expirations shall only cause the device to transition from higher power conditions to lower power conditions (e.g., if the standby timer is set to a smaller interval than the Idle2 timer, the device shall remain in the standby condition when the Idle2 timer expires). 06/10/2008 Page 3 of 24
5 Changes to clause 5 (No changes) 6 Changes to clause 6 (No changes) 06/10/2008 Page 4 of 24
7 Changes to clause 7 7.1.1 SET FEATURES - EFh, Non-Data 7.1.1.1 Feature Set 7.1.1.2 Value Table 53 - SET FEATURES Feature field definitions (part X of 3) TBDSF Extended Power conditions (See 7.1.1.3) 7.1.1.3 Extended Power Conditions (EPC) Subcommand code TBDSF enables, disables, and configures the use of the Extended Power Conditions feature set (see 4.3.4). If the EPC feature is not supported, then the device shall return command aborted. 7.1.1.4 Inputs for SET FEATURES - Extended Power Conditions Name Feature Count LBA Device Command TBDSF (set features subcommand code) EPC subcommand dependent 23:16 EPC subcommand dependent 15:8 EPC subcommand dependent 7:0 Extended Power Conditions subcommand (See Table 1) 15 Obsolete 14 Shall be set to one 13 Obsolete 12 Transport Dependent - See 11:8 Reserved 7:0 EFh 06/10/2008 Page 5 of 24
Table 1 - Extended Power Conditions Subcommands EPC Subcommand EPC Subcommand 00h 01h 02h 03h 04h 05h.. FFh Reset to power-on defaults Go immediately to selected EPC power condition Set EPC timer value Enable EPC operation with existing timer values Disable EPC operation Reserved Power Condition ID 00h.. 80h Power Condition Name Reserved Table 2 - Power Condition IDs 81h Idle1 A substate of the PM1:Idle state, Idle1 may consume more power than Idle2 82h Idle2 A substate of the PM1:Idle state, Idle2 may consume more power than Idle3 83h Idle3 A substate of the PM1:Idle state, Idle3 may consume more power than when the device is in the PM2:Standby state 84h.. FFh Reserved 06/10/2008 Page 6 of 24
7.48.new.1 EPC Reset to Defaults subcommand On successful completion of this EPC subcommand, all EPC timers shall be set to the to power-on default values for the device. In addition, IDENTIFY DEVICE data word TBDB bit TBD1 shall be cleared to zero, indicating that the use of the EPC timers is disabled. See Table 4 for normal outputs. 7.1.1.5 Inputs for EPC Reset to Defaults subcommand Name Feature Count LBA Device Command TBDSF (set features subcommand code) Reserved 23:16 Reserved 15:8 Reserved 7:0 00h = Reset power management to default timers 15 Obsolete 14 Shall be set to one 13 Obsolete 12 Transport Dependent - See 11:8 Reserved 7:0 EFh 06/10/2008 Page 7 of 24
7.48.new.2 EPC Go Immediately to Selected Power Condition subcommand On successful completion of this EPC subcommand, the device shall enter the selected EPC power condition after command completion without having to wait for any timers to expire. In addition, IDENTIFY DEVICE data word TBDB bit TBD1 shall be set to one, indicating that the use of the EPC timers is enabled. See Table 4 for normal outputs. 7.1.1.6 Inputs for EPC Go Immediately to Selected Power Condition subcommand Name Feature TBDSF (set features subcommand code) Count Power condition ID (see Table 2) LBA 23:16 Reserved 15:8 Reserved 7:0 01h = Go Immediately to Selected Power Condition Device 15 Obsolete 14 Shall be set to one 13 Obsolete 12 Transport Dependent - See 11:8 Reserved Command 7:0 EFh 06/10/2008 Page 8 of 24
7.48.new.3 EPC Set Timer Value subcommand On successful completion of this EPC subcommand, the device shall associate the selected EPC power condition with the selected timer value. This setting shall persist across all resets. In addition, IDENTIFY DEVICE data word TBDB bit TBD1 shall be set to one, indicating that the use of the EPC timers is enabled. See Table 5 for normal outputs. A timer value of zero shall disable the timer associated with the Power condition ID. 7.1.1.7 Inputs for EPC Set Timer Value for Power Condition subcommand Name Feature TBDSF (set features subcommand code) Count Power condition ID (see Table 2) LBA 23:8 Timer value (15:0) 7:0 02h = Set Power Condition Timer Value Device 15 Obsolete 14 Shall be set to one 13 Obsolete 12 Transport Dependent - See 11:8 Reserved Command 7:0 EFh 06/10/2008 Page 9 of 24
7.48.new.4 EPC Enable operations with existing timers subcommand On successful completion of this EPC subcommand, the device shall enable the use of the EPC timers without changing their saved values. In addition, IDENTIFY DEVICE data word TBDB bit TBD1 shall be set to one, indicating that the use of the EPC timers is enabled. See Table 3 for normal outputs. 7.1.1.8 Inputs for EPC Enable operations with existing timers subcommand Name Feature Count LBA Device Command TBDSF (set features subcommand code) Reserved 23:8 Reserved 7:0 03h = Enable EPC operation with existing timers 15 Obsolete 14 Shall be set to one 13 Obsolete 12 Transport Dependent - See 11:8 Reserved 7:0 EFh 06/10/2008 Page 10 of 24
7.48.new.5 EPC Disable operations subcommand On successful completion of this EPC subcommand, the device disable the use of the EPC timers and shall preserve any saved values. In addition, IDENTIFY DEVICE data word TBDB bit TBD1 shall be cleared to zero, indicating that the use of the EPC timers is disabled. See Table 3 for normal outputs. 7.1.1.9 Inputs for EPC disable operations subcommand Name Feature Count LBA Device Command TBDSF (set features subcommand code) Reserved 23:8 Reserved 7:0 04h = Disable EPC operations 15 Obsolete 14 Shall be set to one 13 Obsolete 12 Transport Dependent - See 11:8 Reserved 7:0 EFh 06/10/2008 Page 11 of 24
7.1.1.10 Normal Outputs See Table 3, Table 4 and Table 5 for normal outputs of the EPC subcommand 7.1.1.11 Error Outputs (No changes) 06/10/2008 Page 12 of 24
7.1.2 Changes to DCO IDENTIFY. Word Content TBDDCOCommand set/feature set supported TBD1 1 = Reporting support for Extended Power Conditions is changeable If bit TBD1 of Word TBDDCO is set to one, then support for the Extended Power Conditions feature is changeable. 7.1.3 Changes to DCO SET Word Content TBDDCOCommand set/feature set supported TBD1 1 = Reporting support for Extended Power Conditions is allowed If bit TBD1 of Word TBDDCO is cleared to zero, the device shall a) disable support for the Extended Power Conditions feature; b) clear bit TBD1 of word TBDIDA in the IDENTIFY DEVICE data to zero; c) clear bit TBD1 of word TBDIDB in the IDENTIFY DEVICE data to zero. 06/10/2008 Page 13 of 24
7.1.4 Changes to IDENTIFY DEVICE data If the proposal adds a feature set or command, there should be an addition to the IDENTIFY DEVICE data to indicate both supported and enabled descriptions. Fill in the description in the table and place a description of each bit or word underneath the table. Word O M TBDIDA M S P F V Supported Settings F TBD1 1 = Extended Power Conditions feature set is supported TBDIDB M F Enabled Settings TBD1 1 = Extended Power Conditions timer use is enabled Key: O/M Mandatory/optional requirement. M Support of the word is mandatory. O Support of the word is optional. F/V Fixed/variable content F The content of the field is fixed and does not change. The DCO command may change the value of a fixed field. For removable media devices, these values may change when media is removed or changed. V The contents of the field is variable and may change depending on the state of the device or the commands executed by the device. X The content of the field may be fixed or variable S/P Content applies to Serial or Parallel transport S Serial Transport P Parallel Transport B Both Serial and Parallel Transports N Belongs to a transport other than Serial or Parallel Word TBDIDA, bit TBD 1 shall be set to one if the Extended Power Conditions feature is supported. (See XXXX) Word TBDIDB, bit TBD 1 shall be set to one if the Extended Power Conditions feature is enabled. When this is enabled, the EPC timers may be used. When this is disabled, the EPC timers shall not be available for use. (See XXXX) 06/10/2008 Page 14 of 24
7.2 Changes to Normal and Error Outputs 7.2.1 Changes to Normal Outputs Table 103 - Check Power Mode Normal Output Name Error Count N/A Value 00h Device is in the PM2: Standby state. 40h Device is in the PM0: Active state, and the NV Cache power mode is enabled and the spindle is spun down or spinning down. 41h Device is in the PM0: Active state and the NV Cache power mode is enabled and the spindle is spun up or spinning up. 80h Device is in the PM1: Idle state and Extended Power Conditions is (not supported or not enabled) 81hDevice is in the PM1: Idle State, and Extended Power Conditions is supported and enabled, and the device is in the Idle1 power condition. 82hDevice is in the PM1: Idle State, and Extended Power Conditions is supported and enabled, and the device is in the Idle2 power condition. 83hDevice is in the PM1: Idle State, and Extended Power Conditions is supported and enabled, and the device is in the Idle3 power condition. FFh Device is in the PM0: Active state or PM1: Idle State. LBA Device Status N/A 15 Obsolete 14 N/A 13 Obsolete 12 Transport Dependent - See 11:8 Reserved 7:6 Transport Dependent - See. 5 Device Fault - See 4 N/A 3 Transport Dependent - See. 2:1 N/A 0 Error - See 06/10/2008 Page 15 of 24
Table 3 - Normal outputs for SET FEATURES Extended Power Conditions - subcommands 00h, 03h, 04h Name Error Count LBA Device Status Reserved 23:16 Reserved 15:8 Reserved 7:0Extended Power Conditions subcommand (See Table 1) 15 Obsolete 14 N/A 13 Obsolete 12 Transport Dependent - See 11:8 Reserved 7:6 Transport Dependent - See. 5 Device Fault - See 4 N/A 3 Transport Dependent - See. 2:1 N/A 0 Error - See Table 4 - Normal outputs for SET FEATURES Extended Power Conditions - subcommand 01h Name Error Count Power condition ID (see Table 2) LBA 23:16 Reserved 15:8 Reserved 7:0Extended Power Conditions subcommand (See Table 1) Device 15 Obsolete 14 N/A 13 Obsolete 12 Transport Dependent - See 11:8 Reserved Status 7:6 Transport Dependent - See. 5 Device Fault - See 4 N/A 3 Transport Dependent - See. 2:1 N/A 0 Error - See 06/10/2008 Page 16 of 24
Table 5 - Normal outputs for SET FEATURES Extended Power Conditions - subcommand 02h Name Error Count Power condition ID (see Table 2) LBA 23:8 Timer value (in 100 ms units) 7:0 Extended Power Conditions subcommand (See Table 1) Device 15 Obsolete 14 N/A 13 Obsolete 12 Transport Dependent - See 11:8 Reserved Status 7:6 Transport Dependent - See. 5 Device Fault - See 4 N/A 3 Transport Dependent - See. 2:1 N/A 0 Error - See 7.2.2 Changes to Error Outputs None. 06/10/2008 Page 17 of 24
Changes to Annex A Log Definitions Changes to Table A.2 Add new row: Log Number Log Name Feature set R/W Access TBDLOG Power Conditions Extended Power Conditions RO GPL 7.2.3 (new log) Power Conditions Log (TBDLOG) If the Extended Power Conditions feature set is supported, then this log shall be supported. Idle1 timer properties : Update Criteria: This value reports the properties of the Idle1 power condition Update prior to entering into any power condition that prevents accessing the media: Yes Update on EPC command execution: yes Word DataType 00h word Flags Bits 15:8 Power condition ID (see Table 2) 7:3 Reserved 2 1= Idle1 timer is enabled Cleared to zero at power-on reset = yes Preserve over all other resets = yes 1 1= Idle1 timer has been changed since the last power-on reset Cleared to zero at power-on reset = no Preserve over all other resets = yes 0 1= Idle1 timer is changeable Initialized at time of manufacture = yes Preserve over all other resets = yes 06/10/2008 Page 18 of 24
01h word Maximum Recovery time from Idle1 to PM0:Active This is the maximum time required to transition from Idle1 to PM0: Active. This time doesn t include processing time for the command that caused this transition to occur. A value of zero indicates that the maximum recovery time is not specified. Measurement Units: unsigned 100s of millisecs Initialized at the time of manufacture = yes Preserve over all resets = yes 02h word Reserved 03h word Manufacturer default Idle1 timer setting This is the time that the device shall wait after command completion before entering the Idle1 power condition of the PM1:Idle power management state. A value of zero indicates that this power condition is disabled. Measurement Units: unsigned 100s of millisecs At the time of manufacture = yes Preserve over all resets = yes 04h word User defined Idle1 timer setting This is the time that the device shall wait after command completion before entering the Idle1 power condition of the PM1:Idle power management state. A value of zero indicates that this power condition is disabled. Measurement Units: unsigned 100s of millisecs 05h..0Fh Idle2 timer properties : Update Criteria: Cleared to 0 at the time of manufacture = yes Preserve over all resets = yes Reserved for Idle1 parameters This value reports the properties of the Idle2 power condition Update prior to entering into any power condition that prevents accessing the media: Yes Update on EPC command execution: yes Word DataType 10h word Flags Bits 15:8 Power condition ID (see Table 2) 7:3 Reserved 2 1= Idle2 timer is enabled Cleared to zero at power-on reset = yes Preserve over all other resets = yes 06/10/2008 Page 19 of 24
1 1= Idle2 timer has been changed since the last power-on reset Cleared to zero at power-on reset = no Preserve over all other resets = yes 0 1= Idle2 timer is changeable Initialized at time of manufacture = yes Preserve over all other resets = yes 11h word Maximum Recovery time from Idle2 to PM0:Active This is the maximum time required to transition from Idle2 to PM0: Active. This time doesn t include processing time for the command that caused this transition to occur. A value of zero indicates that the maximum recovery time is not specified. Measurement Units: unsigned 100s of millisecs Initialized at the time of manufacture = yes Preserve over all resets = yes 12h word Reserved 13h word Manufacturer default Idle2 timer setting This is the time that the device shall wait after command completion before entering the Idle2 power condition of the PM1:Idle power management state. A value of zero indicates that this power condition is disabled. Measurement Units: unsigned 100s of millisecs At the time of manufacture = yes Preserve over all resets = yes 14h word User defined Idle2 timer setting This is the time that the device shall wait after command completion before entering the Idle2 power condition of the PM1:Idle power management state. A value of zero indicates that this power condition is disabled. Measurement Units: unsigned 100s of millisecs 15h..1Fh Idle3 timer properties : Update Criteria: Cleared to 0 at the time of manufacture = yes Preserve over all resets = yes Reserved for Idle2 parameters This value reports the properties of the Idle3 power condition Update prior to entering into any power condition that prevents accessing the media: Yes Update on EPC command execution: yes Word DataType 20h word Flags Bits 15:8 Power condition ID (see Table 2) 06/10/2008 Page 20 of 24
7:3 Reserved 2 1= Idle3 timer is enabled Cleared to zero at power-on reset = yes Preserve over all other resets = yes 1 1= Idle3 timer has been changed since the last power-on reset Cleared to zero at power-on reset = no Preserve over all other resets = yes 0 1= Idle3 timer is changeable Initialized at time of manufacture = yes Preserve over all other resets = yes 21h Word Maximum Recovery time from Idle3 to PM0:Active This is the maximum time required to transition from Idle3 to PM0: Active. This time doesn t include processing time for the command that caused this transition to occur. A value of zero indicates that the maximum recovery time is not specified. Measurement Units: unsigned 100s of millisecs Initialized at the time of manufacture = yes Preserve over all resets = yes 22h word Reserved 23h word Manufacturer default Idle3 timer setting This is the time that the device shall wait after command completion before entering the Idle3 power condition of the PM1:Idle power management state. A value of zero indicates that this power condition is disabled. Measurement Units: unsigned 100s of millisecs At the time of manufacture = yes Preserve over all resets = yes 24h word User defined Idle3 timer setting This is the time that the device shall wait after command completion before entering the Idle3 power condition of the PM1:Idle power management state. A value of zero indicates that this power condition is disabled. Measurement Units: unsigned 100s of millisecs 25h..2Fh Cleared to 0 at the time of manufacture = yes Preserve over all resets = yes Reserved for Idle3 parameters 06/10/2008 Page 21 of 24
Standby timer properties : This value reports the properties of the PM2:Standby power condition Update Criteria: Update prior to entering into any power condition that prevents accessing the media: Yes Update on EPC command execution: yes Word DataType 30h word Flags Bits 15:8 Reserved 7:3 Reserved 2 1= Standby timer is enabled Cleared to zero at power-on reset = yes Preserve over all other resets = yes 1 1= Standby timer has been changed since the last power-on reset Cleared to zero at power-on reset = no Preserve over all other resets = yes 0 1= Standby timer is changeable 31h word Initialized at time of manufacture = yes Preserve over all other resets = yes Maximum Recovery time from PM2: Standby to PM0:Active This is the maximum time required to transition from PM2: Standby to PM0: Active. This time doesn t include processing time for the command that caused this transition to occur. A value of zero indicates that the maximum recovery time is not specified. Measurement Units: unsigned 100s of millisecs Initialized at the time of manufacture = yes Preserve over all resets = yes 32h word Reserved 33h word Manufacturer default Standby timer setting This is the time that the device shall wait after command completion before entering the PM2: Standby power management state. A value of zero indicates that this power condition is disabled. 15:8 Reserved Measurement Units: 7:0 (See Table 41 in ATA8-ACS) At the time of manufacture = yes Preserve over all resets = yes 06/10/2008 Page 22 of 24
34h word User defined Standby timer setting This is the time that the device shall wait after command completion before entering the PM2: Standby power management state. A value of zero indicates that this power condition is disabled. 15:8 Reserved Measurement Units: 7:0 (See Table 41 in ATA8-ACS) 35h..3Fh Cleared to 0 at the time of manufacture = yes Preserve over all resets = yes Reserved for Standby parameters 40..FFh Reserved (to the end of page 0000h) 06/10/2008 Page 23 of 24
7.3 Changes to Annex B - Command Set Summary 7.3.1 Changes to the Command Matrix Table None. 7.3.2 Changes to the Command Codes Table None. 7.3.3 Changes to the Historical Command Assignments Table (suggested change to column labeling/formatting only) Op Code Command 1 2 3 ATA/ATAPI- 4 5 6 7 ATA8 - ACS TBD Your Command Name C C C C C C C C TBD Your Command Name R R R R R R R R Key: C = a defined command. E = a retired command. O = Obsolete. R = Reserved, undefined in current specifications. V = Vendor specific commands. ACS - 2 A = Reserved for assignment by the CompactFlash Association F = If the device does not implement the CFA feature set, this command code is Vendor specific. M = Reserved for the Media Card Pass Through Command feature set. S = Reserved for Serial ATA *Indicates this definition is new to ATA8 7.3.4 Changes to the Historical Set Feature Code Assignments Table (suggested change to column labeling/formatting, plus adding EPC feature) Feature ATA/ATAPI- ATA8 - ACS Code 1 2 3 4 5 6 7 ACS - 2 TBDSF Extended Power Conditions R R R R R R R R C Key: C = a defined command. E = a retired command. O = Obsolete. R = Reserved, undefined in current specifications. V = Vendor specific commands. A = Reserved for assignment by the CompactFlash? Association. F = If the device does not implement the CFA feature set, this command code is Vendor specific. M = Reserved for the Media Card Pass Through Command feature set. S = Reserved for Serial ATA. T = Reserved for Technical Report T13/DT1696 (Time-Limited Commands). 06/10/2008 Page 24 of 24