Manuals / Fujitsu / Computer Equipment / Computer Drive

Fujitsu MHW2100BS, MHW2080BS, MHW2120BS Caching operation, Commands that are targets of caching

Models: MHW2040BS MHW2100BS MHW2060BS MHW2120BS MHW2080BS

1 296

Download 296 pages 17.62 Kb

Page 270

Operations

6.4.2 Caching operation

The caching operation is performed only when the commands listed below are received. If any of the following data are stored on the data buffer, the data is sent to the host system.

•

•

All of the sector data that this command processes.

A part of the sector data including the start sector, that this command processes.

If part of the data to be processed is stored on the data buffer, the remaining data is read from disk media and sent to the host system.

(1) Commands that are targets of caching

The commands that are targets of caching are as follows:

•

•

•

•

READ SECTOR (S) (EXT)

READ MULTIPLE (EXT)

READ DMA (EXT)

READ FP DMA QUEUED

However, if the caching function is prohibited by the SET FEATURES command, the caching operation is not performed.

(2) Data that is a target of caching

The data that is a target of caching are as follows:

1)Read-ahead data that is read from disk media and saved to the data buffer upon completion of execution of a command that is a target of caching.

2)Pre-read data that is read from disk media and saved to the data buffer before execution of a command that is a target of caching.

3)Data required by a command that is a target of caching and has been sent to the host system one. If the sector data requested by the host has not been completely stored in the read cache portion of the buffer, this data does not become a target of caching. Also, If sequential hits occur continuously, the caching-target data required by the host becomes invalid because that data is overwrited by new data.

6-14

C141-E249

Image 270

Fujitsu MHW2100BS, MHW2080BS Caching operation, Commands that are targets of caching, Data that is a target of caching

Contents

Disk Drives Product Manual For Safe Operation Handling of This Manual Revision History This page is intentionally left blank Overview of Manual Conventions for Alert Messages Operating EnvironmentConventions Liability Exception This page is intentionally left blank Important Alert Items Important Alert Messages This page is intentionally left blank Disk Drives Maintenance Manual Disk Drives Product Manual This page is intentionally left blank Contents Installation Conditions Theory of Device Operation Contents Interface 101 Operations GL-1 AB-1IN-1 Illustrations 171 Recommended connector specifications for the host Tables 106 Device Overview Features Functions and performanceAdaptability High resistance against shock Error correction and retry by ECCLow noise and vibration Connection to Sata interface Device Specifications Specifications summarySpecifications 1/2 Model and product number Examples of model names and product numbers Ripple Power RequirementsInput Voltage Slope of an input voltage at rise Power Requirements Current Requirements and Power Dissipation Current and power dissipation Environmental Specifications Current fluctuation Typ. at +5 V when power is turned onEnvironmental specifications Acoustic Noise Acoustic noise specificationShock and vibration specification Shock and Vibration MTBF= Service lifeData assurance in the event of power failure Mean time to repair Mttr Positioning error Error RateUnrecoverable read error Media Defects Advanced Power Management APM Recommended power-off sequence Advanced Power Management Interface Power Management IPM Host-initiated interface power management HipmDevice-initiated interface power management Dipm Interface power management Device Configuration Device Configuration Drive connection System ConfigurationSata interface Read/write circuit This page is intentionally left blank Installation Conditions Dimensions Dimensions Mounting OrientationFrame Limitation of mounting PCA Location of breather Ambient temperature Service area Handling cautions ESD Hios Device connector Connections with Host System Connector specifications for host system Signal segment and power supply segmentRecommended connector specifications for the host system Sata interface cable connection This page is intentionally left blank Theory of Device Operation Disk OutlineSubassemblies Spindle Servo circuit Circuit ConfigurationAir filter Spindle motor driver circuit Power supply configuration PCA Power-on Sequence Power-on operation sequence Self-calibration contents Self-calibration Command processing during self-calibration Execution timing of self-calibration Write circuit Read/write CircuitRead/write preamplifier PreAMP Write precompensation Read circuit AGC circuitProgrammable filter circuit D converter circuit Digital PLL circuitFIR circuit Viterbi detection circuit Servo Control Servo control circuit Servo burst capture circuit Power amplifierMicroprocessor unit MPU A converter DAC Data-surface servo format Physical sector servo configuration on disk surface Servo frame format Seek operation Actuator motor controlOperation to move the head to the reference cylinder Track following operation Stable rotation mode Start modeAcceleration mode Spindle motor control This page is intentionally left blank Interface Interface signals Physical Interface Comreset / Cominit Comwake5VDC/GND Signal interface regulation Out of band signaling EOF AlignCont Pmack Rrdy RIPROK SOF Electrical specifications FER Physical Layer Electrical Requirements 2/3 COMINIT/COMRESET Physical Layer Electrical Requirements 3/3 Connector pinouts Connector pinouts Driving Ready LED 5 P11 functionStaggered Spin-up Requirements for P11 as an output pin Example of the circuit for driving Ready LED Hot Plug Conceptual diagram of communication layers Logical Interface Link layer Communication layersPhysical layer Transport layer Outline of the Shadow Block Register Shadow Block Register 3.2 Outline of the frame information structure FISFIS types Register Host to Device FIS layout Register Device to Host DMA Active Device to Host DMA Setup Device to Host or Host to Device Bidirectional TAG Bist Active Bidirectional Bist combinations PIO Setup Device to Host Data Host to Device or Device to Host BidirectionalData FIS Bidirectional layout Block at the conclusion of all subsequent Data to Device Set Device Bits Device to Host 11 Set Device Bits FIS Error Field Shadow block registersUNC Sector Number Field exp Features Field expSector Count Field exp Cylinder Low Field exp HS3 HS2 HS1 HS0 Cylinder High Field expDevice/Head Field HS3 Status field Bit Device Write Fault DF bitBit Error ERR bit Bit 7 Busy BSY bit Device Control Field Command FieldBit 2 Software Reset Srst EStatus Field Host Commands Command code and parametersCommand code and parameters 1/3 Command code and parameters 2/3 Command code and parameters 3/3 Command descriptions Error reporting conditions Recalibrate X’10’ to X’1F’ Read Sectors X’20’ or X’21’ LBA LBA LSB Write Sectors X’30’ or X’31’ 00 *1 Error information Write Verify X’3C’ Host Commands Read Verify Sectors X’40’ or X’41’ Host Commands Seek X’70’ to X’7F’ Execute Device Diagnostic X’90’ Diagnostic code Initialize Device Parameters X’91’ Download Microcode X’92’ Operation of Download Microcode Error reporting conditions Standby Immediate X’94’ or X’E0’ Interface Unload Feature Unload Immediate Command Standby X’96’ or X’E2’ Idle X’97’ or X’E3’ Interface Check Power Mode X’98’ or X’E5’ ’FF’ Comreset Sleep X’99’ or X’E6’ Smart X’B0’ 10 Features Field values subcommands and functions 1/3 Smart Read LOG 10 Features Field values subcommands and functions 2/3Smart Enable Operations Smart Write LOG ’DB’ Smart ENABLE/DISABLE Auto OFF-LINE 10 Features Field values subcommands and functions 3/3Smart Disable Operations ’DA’ Smart Return Status Key C2h 12 Format of guarantee failure threshold value data 11 Format of device attribute value data1FF Data format version number Attribute ID Attribute value for the worst case so far Status FlagCurrent attribute value Raw attribute value 13 Off-line data collection status Self-test execution status14 Self-test execution status 17 Drive error logging capability 15 Off-line data collection capability16 Failure prediction capability flag Checksum Guarantee failure thresholdSmart error logging 18 Log Directory Data Format 19 Data format of Smart Summary Error Log 1/2 Error data structure 19 Data format of Smart Summary Error Log 2/2Command data structure Total number of drive errors 20 Data format of Smart Comprehensive Error Log Smart Self-Test Self-test number Self-test index 22 Selective self-test log data structure Test SpanCurrent LBA under test Current Span under test Feature Flags23 Selective self-test feature flags Selective Self-test pending time min Smart Command Transport SCT 24 SCT command and the function SCT Status Request SN = E0h, FR = D5h 25 Format of SCT Status Response 1/2 SET MAX EXT, DCO 25 Format of SCT Status Response 2/2 26 SCT Status code SCT Command SET SN = E0h, FR = D6 27 Action code 28 Write Same 1/2 29 Error Recovery Control 28 Write Same 2/2 30 Feature Control Command Feature Control Command 31 SCT Data Table 32 had Temperature SCT Read Data SN = E1h, FR = D5 SCT Write Data SN = E1h, FR = D6 Device Configuration Freeze Device Configuration XB1Device Configuration Restore Device Configuration Identify Device Configuration Restore Features Field = C0h Device Configuration Freeze Lock Features Field = C1h Device Configuration Identify Features Field = C2h Device Configuration SET Features Field = C3h 33 Device Configuration Identify data structure 1/2 Word Value Content 33 Device Configuration Identify data structure 2/2 Read Multiple X’C4’ 12 Execution example of Read Multiple command Start sector No Write Multiple X’C5’ Start sector No SET Multiple Mode X’C6’ Interface Read DMA X’C8’ or X’C9’ MSB / LBA LSB / LBA Write DMA X’CA’ or X’CB’ Interface Read Buffer X’E4’ Flush Cache X’E7’ Write Buffer X’E8’ Identify Device X’EC’ Identify Device DMA X’EE’ 34 Information to be read by Identify Device command 1/3 ’3FFF’ 34 Information to be read by Identify Device command 2/3 34 Information to be read by Identify Device command 3/3 MHW2120BS MHW2100BS MHW2080BS MHW2060BS MHW2040BS ’3FFF’ Command without interrupt supports 2, 4, 8 and 16 sectors Host Commands Interface C141-E249 113 Interface C141-E249 115 Bit = Supports the Mode Word C141-E249 117 = SCT Error Recovery Control supported SET Features X’EF’ 35 Features field values and settable modes 1/2 35 Features field values and settable modes 2/2 See Table Data Transfer Mode Advanced Power Management APM Serial ATA Functions Write-Read-Verify feature optional 36 Write-Read-Verify feature sector countsAutomatic Acoustic Management AAM 37 Contents of Security SET Password data Error reporting conditions When the master password is selected When the user password is selectedSecurity UNLOCKX’F2’ Host Commands Security Erase Prepare X’F3’ Security Erase Unit X’F4’ Security Freeze Lock X’F5’ Error reporting conditions 39 Contents of security password Error reporting conditions Read Native MAX Address X’F8’ Lbalsb SET MAX X’F9’ SET MAX Address SET MAX SET Password Features Field = 01h Password information SET MAX Lock Features Field = 02h DH CH CL SN SC ER SET MAX Unlock Features Field = 03h SET MAX Freeze Lock Features Field = 04h Read Sector S EXT X’24’ Description CL EXPSN EXP Read DMA EXT X’25’ Description Read Native MAX Address EXT X’27’ Read Multiple EXT X’29’ Read LOG EXT X2F CL EXP SN EXP 40 Data format of Read Log Ext log page 10h 41 Tag field information 42 Data format of Read Log Ext log page 11h 43 Counter Identifier information SCT Status Request SN = E0h SC EXP Error information 152 C141-E249 Write Sector S EXT X’34’ Description Write DMA EXT X’35’ Description SET MAX Address EXT X’37’ SET MAX LBA Write Multiple EXT X’39’ Write LOG EXT X3F Error information C141-E249 159 SCT Command SET SN = E0h SCT Write Data SN = E1h Read Verify Sector S EXT X’42’ Flush Cache EXT X’EA’ Write Multiple FUA EXT XCE Write DMA FUA EXT X3D Read FP DMA Queued Write FP DMA Queued Command Name Error posting44 Command code and parameters 1/2 Sfrw Sfrr 44 Command code and parameters 2/2 Execute Device Diagnostic Initialize Device Parameters Command ProtocolNon-data command protocol Data Host PIO data-in command protocol PIO data-out command protocol 14 PIO data-in command protocol 15 PIO data-out command protocol DMA data-in command protocol Read DMA EXT Identfy Device Identfy Device DMA DMA data-out command protocol Write DMA EXT FUA EXT Native Command Queuing protocol Read FP DMA Queued Write FP DMA Queued 18 Read FP DMA Queued command protocol 19 Write FP DMA Queued command protocol Power-on and Comreset 20 Power-on sequence 21 Comreset sequence This page is intentionally left blank Operations Reset and Diagnosis Response to power-on Reset and Diagnosis Response to Comreset Response to Comreset Software settings preservation Comreset preservation requirements SET Address MAX EXT Response to a software reset Response to a software reset Active mode Power SavePower save mode Active idle mode Standby mode Sleep mode Power commands Power Save Controlled by Interface Power Management IPM Power save mode of the interfacePartial mode Slumber mode Example of 8 MB buffer Read-ahead CacheData buffer structure Read Multiple EXT Read DMA EXT Read FP DMA Queued Commands that are targets of caching Caching operationData that is a target of caching Invalidating caching-target data Using the read segment buffer Miss-hit Sequential hit Full hit Partial hit Cache operation Command that are targets of cachingWrite Cache Invalidation of cached data Cashing function when power supply is turned on Status report in the event of an errorComreset and software reset response Enabling and disabling This page is intentionally left blank Connector Connector Plug Host system side Bios standard for drivesCommand Actuator Host receptacle Power save modeRotational delay Master Device Slave Device Seek timeSerial-ATA Status This page is intentionally left blank AIC BiosAbrt Amnf This page is intentionally left blank Index Index Example of model name and product Mode Read/write circuit block diagram Read Native MAX Address Smart summary error log, data Comment Form Japan This page is intentionally left blank C141-E249-01EN Page