| Compaq EV67, 21264

Contents

Revision/Update Information Alpha 21264A MicroprocessorHardware Reference Manual DS-0028A-TEAlpha 21264/EV67 Hardware Reference Manual Table of Contents Hardware Interface Cache and External InterfacesInternal Processor Registers Privileged Architecture Library Code Initialization and Configuration Mffpcr MtfpcrError Detection and Error Handling Testability and DiagnosticsElectrical Data Thermal ManagementAlpha Instruction Set 21264/EV67 Boundary-Scan Register21264/EV67-to-Bcache Pin Interconnections Glossary IndexFigures Xii Tables Xiv VDD Idcpower Page Preface ContentAudience Documentation Included by Reference For example Terminology and ConventionsAbbreviations W1C W1SAddresses Aligned and UnalignedSignal Names Data UnitsDo Not Care ExternalUndefined Do not care. a capital X represents any valid value Page Architecture IntroductionIntroduction Architecture AddressingInteger Data Types Floating-Point Data Types21264/EV67 Microprocessor Features 21264/EV67 Microprocessor Features21264/EV67 Microprocessor Features 21264/EV67 Microarchitecture Internal ArchitectureInternal Architecture 21264/EV67 Microarchitecture Instruction Fetch, Issue, and Retire UnitVirtual Program Counter Logic 21264/EV67 Block Diagram Branch PredictorLocal Predictor Global PredictorChoice Predictor Instruction-Stream Translation BufferInstruction Fetch Logic Integer Issue QueueRegister Rename Maps Floating-Point Issue Queue HwretException and Interrupt Logic Integer Execution UnitRetire Logic PERR, MINxxx, MAXxxx, UNPKxx, PKxx Integer Execution Unit-Clusters 0Floating-Point Execution Unit 10Internal ArchitectureOnchip Caches External Cache and System Interface Unit21264/EV67 contains two onchip primary-level caches Data Cache Memory Reference Unit12Internal Architecture Pipeline Organization Pipeline OrganizationSrom Interface Miss address file MAF Dstream translation buffer DTBStage 1 Instruction Slot Stage 0 Instruction Fetch14Internal Architecture Stage 3 Issue Stage 2 MapInstruction Issue Rules Instruction Issue RulesPipeline Aborts Ebox and Fbox pipelines begin executionInstruction Issue Rules Instruction Group Definitions Instruction Name, Pipeline, and TypesEbox Slotting FTOIS, FtoitITOFS, ITOFF, Itoft Instruction Group Definitions and Pipeline UnitU U L E L U E E L L E U Instruction Issue Rules Instruction Latencies Instruction Class Latency in CyclesHwmfpr 20Internal ArchitectureInstruction Retire Rules Instruction Retire RulesMinimum Retire Latencies for Instruction Classes Retire of Operate Instructions into R31/F31 Retire of Operate Instructions into R31/F31Floating-Point Divide/Square Root Early Retire BSR/JSRLoad Instructions to R31 and F31 Load Instructions to R31 and F31Prefetch with Modify Intent LDS Instruction Instructions Retired Without ExecutionSpecial Cases of Alpha Instruction Execution Prefetch with the LDxL / STxC Instruction SequenceLoad Hit Speculation 24Internal ArchitectureSpecial Cases of Alpha Instruction Execution Pipeline Timing for Integer Load InstructionsCmov Instruction Floating-Point Store Instructions26Internal Architecture Memory and I/O Address Space Instructions Memory and I/O Address Space InstructionsMemory Address Space Load Instructions Rules for I/O Address Space Load Instruction Data Merging 2 I/O Address Space Load Instructions28Internal Architecture 8shows some of the following rules 4 I/O Address Space Store InstructionsRules for I/O Address Space Store Instruction Data Merging MAF Memory Address Space Merging Rules Instruction OrderingMAF Memory Address Space Merging Rules MAF Merging RulesReplay Traps Replay TrapsMbox Order Traps 10 Memory Reference Ordering12 I/O Write Buffer and the WMB Instruction Write Buffer and the WMB InstructionOther Mbox Replay Traps Memory Barrier MB/WMB/TB Fill FlowMB Instruction Processing WMB Instruction Processing TB Fill Flow12 TB Fill Flow Example Sequence 34Internal Architecture13 TB Fill Flow Example Sequence Performance Measurement Support-Performance Counters Floating-Point Control RegisterPerformance Measurement Support-Performance Counters Floating-point control register Fpcr is shown in FigureFloating-Point Control Register Amask and Implver Instruction Values Amask and Implver Instruction ValuesAmask ImplverDesign Examples Design Examples13 Typical Multiprocessor Configuration 40Internal ArchitectureHardware Interface 21264/EV67 Microprocessor Logic SymbolHardware Interface 21264/EV67 Microprocessor Logic Symbol 21264/EV67 Microprocessor Logic Symbol21264/EV67 Signal Names and Functions 21264/EV67 Signal Names and FunctionsSignal Pin Types Definitions 21264/EV67 Signal DescriptionsDcokh Pllvdd 21264/EV67 Signal Descriptions by Function TestStatHSysVref Domain SysAddInL140 Pin Assignments Pin List Sorted by Signal NamePin Assignments AC1 10Hardware Interface PllvddAA5 Pin List Sorted by PGA Location 12Hardware InterfaceSysDataL28 14Hardware Interface BcDataH70 SysDataL5 Ground and Power VSS and VDD Pin List 16Hardware InterfaceMechanical Specifications Mechanical Specifications21264/EV67 Packaging 21264/EV67 Packaging18Hardware Interface 21264/EV67 Bottom View Pin Up Page Introduction to the External Interfaces Cache and External InterfacesCache and External Interfaces Introduction to the External Interfaces System Interface 21264/EV67 System and Bcache InterfacesCommands and Addresses Physical Address ConsiderationsPhysical Address Considerations Second-Level Cache Bcache InterfaceECB I/O MB/WMBPhysical Address Considerations Bcache Interface Signals Bcache StructureBcache Structure System Duplicate Tag StoresVictim Data Buffer Cache CoherencyVictim Data Buffer Cache Coherency BasicsCache Coherency Cache Block States2lists the cache block states supported by the 21264/EV67 21264/EV67-Supported Cache Block StatesSystem Responses to 21264/EV67 Commands Cache Block State TransitionsCache Block State Transitions 10Cache and External InterfacesCache Coherency Using SysDc Commands 12Cache and External Interfaces Dcache States and Duplicate Tags Lock Mechanism Lock Mechanism14Cache and External Interfaces Internal Eviction of LDxL Blocks Liveness and FairnessSystem Port System Port16Cache and External Interfaces System Port Pins System Port PinsSystem Port Programming the System Interface Clocks Programming Values for System Interface ClocksProgram Values for Data-Sample/Drive CSRs 18Cache and External InterfacesBank Interleave on Cache Block Boundary Mode 3 21264/EV67-to-System CommandsForwarded Clocks and Frame Clock Ratio Hit Mode 11 Page Hit Mode of Operation12 21264/EV67-to-System Command Fields Definitions 12describes the field definitions for Tables 4-10and4 21264/EV67-to-System Commands Descriptions 14describes the 21264/EV67-to-system commands14 21264/EV67-to-System Commands Descriptions 13 Maximum Physical Address for Short Bus Format22Cache and External Interfaces 15 Programming INVALTODIRTYENABLE10 ProbeResponse Commands Command40 = 16 Programming SETDIRTYENABLE2017 21264/EV67 ProbeResponse Command 24Cache and External Interfaces18describes the ProbeResponse command fields SysAck and 21264/EV67-to-System Commands Flow Control18 ProbeResponse Fields Descriptions System-to-21264/EV67 Commands Probe Commands Four Cycles19 System-to-21264/EV67 Probe Commands RVB RPB20 System-to-21264/EV67 Probe Commands Fields Descriptions 21 lists the data movement selected by Probe4322lists the next cache block state selected by Probe20 21 Data Movement Selection by Probe4323 Data Transfer Command Format Data Transfer Commands Two Cycles28Cache and External Interfaces 24describes the SysDc40 field 24 SysDc40 Field Description8.1 21264/EV67 Clock Basics Data Movement In and Out of the 21264/EV6730Cache and External Interfaces Fast Data Mode 25 Sysclk Cycles Between SysAddOut and SysData 32Cache and External Interfaces26 Cbox CSR SYSDCDELAY40 Examples 26shows four example configurations and shows their useFast Data Disable Mode 27 Four Timing Examples SysDataInValidL and SysDataOutValidLSysDataInValidL 34Cache and External InterfacesSysDataOutValidL SysFillValidL28 Data Wrapping Rules Data Wrapping36Cache and External Interfaces 29 System Wrap and Deliver Data 30defines the interleaved scheme for the wrap order30 Wrap Interleave Order Nonexistent Memory Processing 31defines the wrap order for double-pumped data transfers31 Wrap Order for Double-Pumped Data Transfers 38Cache and External Interfaces21264/EV67 Command NXM Address System/21264/EV67 Response Ordering of System Port Transactions 10.1 21264/EV67 Commands and System Probes40Cache and External Interfaces System Port Bcache Port Bcache Port36 Bcache Port Pins Bcache Port Pins35 Range of Maximum Bcache Clock Ratios Bcache Clocking 44Cache and External Interfaces38 BCCLKDELAY10 Values 37 BCCPUCLKDELAY10 ValuesSetting the Period of the Cache Clock 39 Program Values to Set the Cache Clock Period Single-Data 46Cache and External Interfaces41 Data-Sample/Drive Cbox CSRs Bcache TransactionsBcache Data Read and Tag Read Transactions Bcache Data Write Transactions 48Cache and External InterfacesWhen the ratio is even, bcfrm is equal to the ratio When the ratio is odd, bcfrm is twice the ratioFor example, in single-data mode Dual-data mode, bcfrm is twice the ratio50Cache and External Interfaces Pin Descriptions Relationship Between Write-to-Read Bcwrrdbubbles and wrrdRelationship Between Read-to-Write Bcrdwrbubbles and rdwr BcAddH23444lists the combination of control pin assertion for 47 Control Pin Assertion for Ramtype D 46 Control Pin Assertion for Ramtype CBcDataInClkH and BcTagInClkH Interrupts Interrupts Bcache BankingDisabling the Bcache for Debugging 54Cache and External InterfacesInternal Processor Registers Internal Processor RegistersMbox IPRs Ebox IPRs Ebox IPRsCycle Counter Register CC Cycle Counter Control Register CcctlVirtual Address Register VA Virtual Address Control Register Vactl2describes the Ccctl register fields Cycle Counter Control Register Fields DescriptionVirtual Address Format Register Vaform 3describes the virtual address control register fieldsVirtual Address Control Register Fields Description VAFORM32Ibox IPRs Ibox IPRsITB Tag Array Write Register Itbtag ITB PTE Array Write Register ItbpteITB Invalidate All Register Itbia ITB Invalidate All Process ASM=0 Register ItbiapITB Invalidate Single Register Itbis Ibox IPRs ProfileMe PC Register Pmpc Exception Address Register Excaddr4describes the ProfileMe PC register fields ProfileMe PC Fields DescriptionInterrupt Enable and Current Processor Mode Register Iercm 13shows Ivaform when ICTLVA48 equals 0 ICTLVAFORM32 equalsIercm Register Fields Description Software Interrupt Request Register Sirr10Internal Processor Registers 6describes the software interrupt request register fields Interrupt Summary Register IsumSoftware Interrupt Request Register Fields Description Hardware Interrupt Clear Register Hwintclr 7describes the interrupt summary register fieldsInterrupt Summary Register Fields Description 12Internal Processor RegistersException Summary Register Excsum 8describes the hardware interrupt clear register fieldsHardware Interrupt Clear Register Fields Description Mchkd W1CException Summary Register Fields Description 9describes the exception summary register fields14Internal Processor Registers PAL Base Register Palbase Ibox Control Register Ictl10describes the PAL base register fields 10 PAL Base Register Fields Description11 Ibox Control Register Fields Description 11describes the Ibox control register fields16Internal Processor Registers Singleissueh MchkenSTWAIT64K PCT1ENSpce Ibox Status Register Istat18Internal Processor Registers 12describes the Ibox status register fields 12 Ibox Status Register Fields DescriptionMIS TRP20Internal Processor Registers Sleep Mode Register Sleep Ibox IPRs Icache Flush Register IcflushIcache Flush ASM Register Icflushasm Clear Virtual-to-Physical Map Register Clrmap14 Process Context Register Fields Description 14describes the process context register fields22Internal Processor Registers FPE Performance Counter Control Register PctrctlPpce 15 Performance Counter Control Register Fields Description 15describes the performance counter control register fields24Internal Processor Registers Mbox IPRs Mbox IPRsDTB Tag Array Write Registers 0 and 1 DTBTAG0, DTBTAG1 16 Performance Counter Control Register Input Select FieldsDTB Alternate Processor Mode Register Dtbaltmode 26Internal Processor Registers17 DTB Alternate Processor Mode Register Fields Description Dstream TB Invalidate All Process ASM=0 Register DtbiapDstream TB Invalidate All Register Dtbia Dstream TB Invalidate Single Registers 0 and 1 DTBIS0,1Memory Management Status Register Mmstat 18describes the memory management status register fields18 Memory Management Status Register Fields Description 28Internal Processor RegistersFor Mbox Control Register MctlACV Erences to superpages result in access violations Dcache Control Register Dcctl19describes the Mbox control register fields 19 Mbox Control Register Fields Description20describes the Dcache control register fields Dcache Status Register Dcstat20 Dcache Control Register Fields Description Cbox CSRs and IPRs Cbox CSRs and IPRs21describes the Dcache status register fields 21 Dcache Status Register Fields DescriptionCbox CSRs and IPRs Cbox Data Register Cdata Cbox Shift Register CshftCbox Writeonce Chain Description 22 describes the Cbox data register fields24 Cbox Writeonce Chain Order 34Internal Processor RegistersMboxbcprbstall BCLATDATAPATTERN031 BCLATTAGPATTERN023 Skewedfillmode36Internal Processor Registers SYSCLKDELAY10 Cbox Writemany Chain Description 38Internal Processor Registers25describes the Cbox Writemany chain order from LSB to MSB 25 Cbox Writemany Chain OrderSetdirtyenable = Bcbankenable = 40Internal Processor RegistersCbox CSRs and IPRs Cbox Read Register IPR Description 26 Cbox Read IPR Fields DescriptionPage PALcode Description Privileged Architecture Library CodePrivileged Architecture Library Code PALmode Environment PALmode EnvironmentRequired PALcode Function Codes Opcodes Reserved for PALcodeRequired PALcode Function Codes Hwld InstructionOpcodes Reserved for PALcode Hwst Instruction3describes the Hwld instruction fields Hwld Instruction Fields Descriptions4describes the Hwst instruction fields Hwret InstructionHwst Instruction Fields Descriptions Hwmfpr and Hwmtpr Instructions 5describes the Hwret instruction fieldsHwret Instruction Fields Descriptions HintInternal Processor Register Access Mechanisms Internal Processor Register Access Mechanisms6describes the Hwmfpr and Hwmtpr instructions fields Hwmfpr and Hwmtpr Instructions Fields DescriptionsHardware Structure of Explicitly Written IPRs IPR Access Ordering Paired Instruction Fetch Order10Privileged Architecture Library Code PALshadow Registers PALcode Emulation of the FpcrPALcode Entry Points PALcode Exception Entry Points PALcode Exception Entry LocationsTranslation Buffer TB Fill Flows Translation Buffer TB Fill FlowsDTB Fill 14Privileged Architecture Library CodeTb miss Wr DataWr PTE LD-PTE, write TB ITB Fill 16Privileged Architecture Library CodePerformance Counter Support Performance Counter SupportGeneral Precautions Aggregate Mode Programming GuidelinesAggregate Mode Precautions IPRs Used for Performance Counter Support10 Aggregate Mode Returned IPR Contents OperationPctrctl SL0 SL111shows the counter modes that are used with Aggregate mode ProfileMe Mode Programming GuidelinesThis input counts Mbox replay traps 12 Cmov Decomposed 13 ProfileMe Mode Returned IPR Contents 22Privileged Architecture Library CodeProfileMe Counting Mode Description Cycle counting Inum retire delay cycles14shows the counter modes that are used with ProfileMe mode Counter Modes for ProfileMe Mode14 ProfileMe Mode Pctrctl Input Select Fields 24Privileged Architecture Library CodeInitialization and Configuration Power-Up Reset Flow and the ResetL and Dcokh Pins21264/EV67 Reset State Machine Major Operations Initialization and ConfigurationPower-Up Reset Flow and the ResetL and Dcokh Pins ConstraintsPower Sequencing and Reset State for Signal Pins Signal Pin Reset StateClock Forwarding and System Clock Ratio Configuration PllvddPin Signal Names and Initialization State PLLPLL Ramp Up BiST and Srom Load and the TestStatH PinClock Forward Reset and System Interface Initialization Power-Up Flow Signals and Their ConstraintsFault Reset Flow Fault Reset FlowEffect on IPRs After Fault Reset Energy Star Certification and Sleep Mode Flow Energy Star Certification and Sleep Mode FlowEffect on IPRs After Transition Through Sleep Mode 10Initialization and ConfigurationWarm Reset Flow Warm Reset FlowSignals and Constraints for the Sleep Mode Sequence Effect on IPRs After Warm ResetInitialization Mode Processing 12Initialization and ConfigurationArray Initialization Array InitializationInitialization Mode Processing EVICTENABLE0Internal Processor Register Power-Up Reset State 10 Internal Processor Registers at Power-Up Reset State14Initialization and Configuration External Interface InitializationInternal Processor Register Power-Up Reset State Ieee 1149.1 Test Port Reset Reset State MachineIeee 1149.1 Test Port Reset 16Initialization and ConfigurationReset State Machine 11 21264/EV67 Reset State Machine State Descriptions18Initialization and Configuration Phase-Lock Loop PLL Functional Description Phase-Lock Loop PLL Functional DescriptionDifferential Reference Clocks PLL Output ClocksPower-Up/Reset Clocking 20Initialization and Configuration21264/EV67 Error Detection Mechanisms Error Detection and Error HandlingError Detection and Error Handling Data Error Correction Code Icache Data or Tag Parity ErrorDcache Tag Parity Error Data Error Correction CodeDcache Data Single-Bit Correctable ECC Error Dcache Data Single-Bit Correctable ECC ErrorLoad Instruction Dcache Store Second Error Dcache Duplicate Tag Parity ErrorDcache Store Second Error Store Instruction Quadword or SmallerBcache Tag Parity Error Bcache Data Single-Bit Correctable ECC ErrorBcache Tag Parity Error Icache Fill from BcacheBcache Victim Read Bcache Victim Read During a Dcache/Bcache MissMemory/System Port Single-Bit Data Correctable ECC Error Memory/System Port Single-Bit Data Correctable ECC ErrorIcache Fill from Memory Dcache Fill from MemoryBcache Data Single-Bit Correctable ECC Error on a Probe Bcache Data Single-Bit Correctable ECC Error on a ProbeDouble-Bit Fill Errors Error Case SummaryDouble-Bit Fill Errors 3summarizes the various error cases and their ramificationsError Case Summary 10Error Detection and Error HandlingMchk Cstatistreammemdbl Mchk CstatdstreambcdblMchk Cstatdstreammemdbl Page Electrical Characteristics Electrical Data1lists the maximum electrical ratings for the 21264/EV67 Maximum Electrical RatingsDC Characteristics DC CharacteristicsSignal Types IdcpowerVDD Idcpower Input DC Reference Pin IdcrefInput Differential Amplifier Receiver IDA Input Differential Amplifier Clock Receiver IdaclkPin Type Open-Drain Driver for Test Pins Oodtp Pin Type Open-Drain Output Driver OODIOZ Codtp11 Push-Pull Output Driver OPP 12 Push-Pull Output Clock Driver OppclkAC Characteristics AC CharacteristicsAC Test Conditions 13 AC Specifications TSU TDHTSU1 TDH2 AC Characteristics Page Operating Temperature Ambient temperature requirementOperating Temperature at Heat Sink Center Tc Thermal ManagementΘca at Various Airflows for 21264/EV67 Operating Temperature10-2Thermal Management Heat Sink Specifications Heat Sink SpecificationsType 1 Heat Sink 10-4Thermal ManagementType 2 Heat Sink Type 3 Heat Sink 10-6Thermal ManagementThermal Design Considerations Thermal Design ConsiderationsPage Testability and Diagnostics Test PinsDedicated Test Port Pins Testability and DiagnosticsSROM/Serial Diagnostic Terminal Port SROM/Serial Diagnostic Terminal Port11-2Testability and Diagnostics Srom Load OperationIeee 1149.1 Port Ieee 1149.1 PortIeee 1149.1 Instructions and Opcodes TestStatH Pin 11-4Testability and DiagnosticsTestStatH Pin Power-Up Self-Test and Initialization Power-Up Self-Test and InitializationBuilt-in Self-Test Srom Initialization11-6Testability and Diagnostics Serial Instruction Cache Load OperationIcache Bit Fields in an Srom Line See Appendix B for a listing of the Boundary-Scan RegisterReferences Page Alpha Instruction Set Alpha Instruction SummaryTable A-1 Instruction Format and Opcode Notation Alpha Instruction Set A-1Alpha Instruction Summary Mbr Branch to subroutine Pcd Trap to PALcodeOpr 11.24 Cmove if = zero Opr 11.46 Cmove if ≥ zero15.0AF Convert Gfloating to quadword 17.010 Convert longword to quadword15.0BC Convert quadword to Ffloating 15.0BE Convert quadword to Gfloating17.02F Fcmove if zero 17.02E Fcmove if ≤ zero17.02C Fcmove if zero 17.02B Fcmove if ≠ zeroOpr 13.40 Multiply longword with integer overflow enable Opr 13.60 Multiply quadword with integer overflow enableOpr 1C.31 Pixel error Mem Load SfloatingOpr 1C.36 Pack words to bytes Mfc 18.E000 Read and clear Mbr 1A.2 Return from subroutineMfc 18.C000 Read process cycle counter 18.F000 Read and set Opr 10.02 Scaled add longword byReserved Opcodes Reserved OpcodesOpcodes Reserved for Compaq Ieee Floating-Point Instructions Ieee Floating-Point Instructions Independent Floating-Point Instructions VAX Floating-Point InstructionsVAX Floating-Point Instructions Opcode Summary Opcode SummaryMem Table A-9explains the symbols used in Table A-8 Mem ResIeee floating-point instruction opcodes Floating-point operate instruction opcodesIeee Floating-Point Conformance Ieee Floating-Point Conformance14Alpha Instruction Set Table A-11 Exceptional Input and Output Conditions Alpha Instruction Set A-15Cmptlt Cmptle Input Cmpteq Cmptun Input16Alpha Instruction Set Fbeq Fbne Fblt Fble Fbgt Fbge LDS LDT STS STT Cpys Cpysn Alpha Instruction Set A-17Page 21264/EV67 Boundary-Scan Register Boundary-Scan RegisterBoundary-Scan Register Pllvdd21264/EV67 Boundary-Scan Register B-3 421264/EV67 Boundary-Scan Register 21264/EV67 Boundary-Scan Register B-5 621264/EV67 Boundary-Scan Register 21264/EV67 Boundary-Scan Register B-7 821264/EV67 Boundary-Scan Register 21264/EV67 Boundary-Scan Register B-9 1021264/EV67 Boundary-Scan Register 21264/EV67 Boundary-Scan Register B-11 1221264/EV67 Boundary-Scan Register Serial Icache Load Predecode Values Serial Icache Load Predecode Values C-1Page PALcode Restrictions and Guidelines PALcode Restrictions and Guidelines D-12PALcode Restrictions and Guidelines PALcode Restrictions and Guidelines D-3 4PALcode Restrictions and Guidelines PALcode Restrictions and Guidelines D-5 Initwritemany6PALcode Restrictions and Guidelines PALcode Restrictions and Guidelines D-7 8PALcode Restrictions and Guidelines Restriction 7 Replay Trap, Interrupt Code Sequence, and STF PALcode Restrictions and Guidelines D-9Restriction 10 Duplicate IPR Mode Bits Restriction 9 PALmode Istream Address RangesRestriction 9 PALmode Istream Address Ranges 10PALcode Restrictions and GuidelinesRestriction 11 Ibox IPR Update Synchronization Restriction 11 Ibox IPR Update SynchronizationRestriction 13 DTB Fill Flow Collision Restriction 14 HwretGuideline 20 Ictlsbe Stream Buffer Enable Guideline 16 JSR-BAD VARestriction 21 HWRET/STALL After Hwmtpr ASN0/ASN1 Guideline 16 JSR-BAD VARestriction 22 HWRET/STALL After Hwmtpr IS0/IS1 Restriction 22 HWRET/STALL After Hwmtpr IS0/IS1PALcode Restrictions and Guidelines D-13 Restriction 25 Hwmtpr Itbia After Reset Guideline 26 Conditional Branches in PALcodeRestriction 24 HWRET/STALL After Hwmtpr ICFLUSH, Icflushasm 14PALcode Restrictions and GuidelinesRestriction 30 Hwmtpr and Hwmfpr to the Cbox CSR Guideline 29 JSR, JMP, RET, and Jsrcor in PALcodePALcode Restrictions and Guidelines D-15 Restriction 30 Hwmtpr and Hwmfpr to the Cbox CSR 16PALcode Restrictions and GuidelinesRestriction 31 ICTLVA48 Update Restriction 32 Pctrctl UpdateRestriction 31 ICTLVA48 Update PALcode Restrictions and Guidelines D-17Guideline 35 Hwintclr Update Restriction 33 Hwld Physical/Lock UseRestriction 36 Updating Ictlsde Restriction 37 Updating VACTLVA48Restriction 40 Scrubbing a Single-Bit Error PALcode Restrictions and Guidelines D-19Restriction 40 Scrubbing a Single-Bit Error 20PALcode Restrictions and GuidelinesRestriction 43 No Trappable Instructions Along with Restriction 42 Updating VACTL, CCCTL, or CC IPRsPALcode Restrictions and Guidelines D-21 Restriction 47 Cache Eviction for Single-Bit Cache Errors 22PALcode Restrictions and GuidelinesRestriction 47 Cache Eviction for Single-Bit Cache Errors PALcode Restrictions and Guidelines D-2324PALcode Restrictions and Guidelines Forwarding Clock Pin Groupings 21264/EV67-to-Bcache Pin InterconnectionsTable E-1 Bcache Forwarding Clock Pin Groupings Late-Write Non-Bursting SSRAMs Late-Write Non-Bursting SSRAMsData Pin Usage Tag Pin UsageDual-Data Rate SSRAMs Dual-Data Rate SSRAMsData and Tag Pin Usage Table E-4 Dual-Data Rate Ssram Data Pin UsageTrstl Table E-5 Dual-Data Rate Ssram Tag Pin UsageGlossary BIU BSR Cisc Cmos CPICPU CSRDMA DramDTB DTLFeprom FETFEU FpgaGclk IDUIowb IpgaITB JfetMAF MBOMBZ MipsMSI Naturally AlignedNmos NvramPAL PGAPLA PlccPqfp PromRAM RASRisc ROMRTL SAMSdram SimmSIP SippStram TTLUart UnalignedUnpredictable UvpromVAF VDFWAR WriteblockIndex NumericsIndex-2 Index-3 Index-4 ECC Index-6 Index-7 Index-8 Index-9 Index-10 Index-11 Index-12

Compaq EV67, 21264 specifications

Models: 21264 EV67