|Port Type||Name||Width (bits)||Description|
This page provides detailed information about the OVP Fast Processor Model of the ARM ARMv4TxM core.
Processor IP owner is ARM Holdings. More information is available from them here.
OVP Fast Processor Model is written in C.
Provides a C API for use in C based platforms.
Provides a native C++ interface for use in SystemC TLM2 platforms.
The model is written using the OVP VMI API that provides a Virtual Machine Interface that defines the behavior of the processor.
The VMI API makes a clear line between model and simulator allowing very good optimization and world class high speed performance.
The model is provided as a binary shared object and is also available as source (different models have different licensing conditions). This allows the download and use of the model binary or the use of the source to explore and modify the model.
The model has been run through an extensive QA and regression testing process.
Traditionally, processor models and simulators make use of one thread on the host PC. Imperas have developed a technology, called QuantumLeap, that makes use of the many host cores found in modern PC/workstations to achieve industry leading simulation performance. To find out about the Imperas parallel simulation lookup Imperas QuantumLeap. There are videos of QuantumLeap on ARM here, and MIPS here. For press information related to QuantumLeap for ARM click here or for MIPS click here. Many of the OVP Fast Processor Models have been qualified to work with QuantumLeap - this is indicated for this model below.
This model executes instructions of the target architecture and provides an interface for debug access. An interface to GDB is provided and this allows the connection of many industry standard debuggers that use the GDB/RSP interface. For more information watch the OVP video here.
The model also works with the Imperas Multicore Debugger and advanced Verification, Analysis and Profiling tools.
An ISS is a software development tool that takes in instructions for a target processor and executes them. The heart of an ISS is the model of the processor. Imperas has developed a range of ISS products for use in embedded software development that utilize this fast Fast Processor Model. The Imperas ARM ARMv4TxM ISS runs on Windows/Linux x86 systems and takes a cross compiled elf file of your program and allows very fast execution. The ARM ARMv4TxM ISS also provides access to standard GDB/RSP debuggers and connects to the Eclipse IDE and Imperas debuggers.
Model downloadable (needs registration and to be logged in) in package arm.model for Windows32 and for Linux32
Model Variant name: ARMv4TxM
ARM Processor Model
Usage of binary model under license governing simulator usage.
Note that for models of ARM CPUs the license includes the following terms:
Licensee is granted a non-exclusive, worldwide, non-transferable, revocable licence to:
If no source is being provided to the Licensee: use and copy only (no modifications rights are granted) the model for the sole purpose of designing, developing, analyzing, debugging, testing, verifying, validating and optimizing software which: (a) (i) is for ARM based systems; and (ii) does not incorporate the ARM Models or any part thereof; and (b) such ARM Models may not be used to emulate an ARM based system to run application software in a production or live environment.
If source code is being provided to the Licensee: use, copy and modify the model for the sole purpose of designing, developing, analyzing, debugging, testing, verifying, validating and optimizing software which: (a) (i) is for ARM based systems; and (ii) does not incorporate the ARM Models or any part thereof; and (b) such ARM Models may not be used to emulate an ARM based system to run application software in a production or live environment.
In the case of any Licensee who is either or both an academic or educational institution the purposes shall be limited to internal use.
Except to the extent that such activity is permitted by applicable law, Licensee shall not reverse engineer, decompile, or disassemble this model. If this model was provided to Licensee in Europe, Licensee shall not reverse engineer, decompile or disassemble the Model for the purposes of error correction.
The License agreement does not entitle Licensee to manufacture in silicon any product based on this model.
The License agreement does not entitle Licensee to use this model for evaluating the validity of any ARM patent.
Source of model available under separate Imperas Software License Agreement.
Instruction pipelines are not modeled in any way. All instructions are assumed to complete immediately. This means that instruction barrier instructions (e.g. ISB, CP15ISB) are treated as NOPs, with the exception of any undefined instruction behavior, which is modeled. The model does not implement speculative fetch behavior. The branch cache is not modeled.
Caches and write buffers are not modeled in any way. All loads, fetches and stores complete immediately and in order, and are fully synchronous (as if the memory was of Strongly Ordered or Device-nGnRnE type). Data barrier instructions (e.g. DSB, CP15DSB) are treated as NOPs, with the exception of any undefined instruction behavior, which is modeled. Cache manipulation instructions are implemented as NOPs, with the exception of any undefined instruction behavior, which is modeled.
Real-world timing effects are not modeled: all instructions are assumed to complete in a single cycle.
Models have been extensively tested by Imperas.
Thumb instructions are supported.
This model implements a number of non-architectural pseudo-registers and other features to facilitate integration.
Halt Reason Introspection:
An artifact register HaltReason can be read to determine the reason or reasons that a processor is halted. This register is a bitfield, with the following encoding: bit 0 indicates the processor has executed a wait-for-event (WFE) instruction; bit 1 indicates the processor has executed a wait-for-interrupt (WFI) instruction; and bit 2 indicates the processor is held in reset.
System Register Access Monitor:
If parameter enableSystemMonitorBus is True, an artifact 32-bit bus "SystemMonitor" is enabled for each PE. Every system register read or write by that PE is then visible as a read or write on this artifact bus, and can therefore be monitored using callbacks installed in the client environment (use opBusReadMonitorAdd/opBusWriteMonitorAdd or icmAddBusReadCallback/icmAddBusWriteCallback, depending on the client API). The format of the address on the bus is as follows:
bits 31:26 - zero
bit 25 - 1 if AArch64 access, 0 if AArch32 access
bit 24 - 1 if non-secure access, 0 if secure access
bits 23:20 - CRm value
bits 19:16 - CRn value
bits 15:12 - op2 value
bits 11:8 - op1 value
bits 7:4 - op0 value (AArch64) or coprocessor number (AArch32)
bits 3:0 - zero
As an example, to view non-secure writes to writes to CNTFRQ_EL0 in AArch64 state, install a write monitor on address range 0x020e0330:0x020e0333.
System Register Implementation:
If parameter enableSystemBus is True, an artifact 32-bit bus "System" is enabled for each PE. Slave callbacks installed on this bus can be used to implement modified system register behavior (use opBusSlaveNew or icmMapExternalMemory, depending on the client API). The format of the address on the bus is the same as for the system monitor bus, described above.
OVP simulator downloadable (needs registration and to be logged in) in package OVPsim for Windows32 and for Linux32
OVP Download page here.
OVP documentation that provides overview information on processor models is available OVP_Guide_To_Using_Processor_Models.pdf.
Full model specific documentation on the variant ARMv4TxM is available OVP_Model_Specific_Information_arm_ARMv4TxM.pdf.
Location: The Fast Processor Model source and object file is found in the installation VLNV tree: arm.ovpworld.org/processor/arm/1.0
Processor Endian-ness: This model can be set to either endian-ness (normally by a pin, or the ELF code).
Processor ELF Code: The ELF code for this model is: 0x28
QuantumLeap Support: The processor model is qualified to run in a QuantumLeap enabled simulator.
The ARMv4TxM OVP Fast Processor Model also has parameters, model commands, and many registers.
The model may also have hierarchy or be multicore and have other attributes and capabilities.
To see this information, please have a look at the model variant specific documents.
Click here to see the detailed document OVP_Model_Specific_Information_arm_ARMv4TxM.pdf.
Information on the ARMv4TxM OVP Fast Processor Model can also be found on other web sites:
www.ovpworld.org has the library pages http://www.ovpworld.org/library/wikka.php?wakka=CategoryProcessor
www.fast-processor-models.org has the page www.fast-processor-models.org/arm_models/armv4txm
www.fast-models.com has the page www.fast-models.com/arm_models/armv4txm
www.model-emulator.com has the page www.model-emulator.com/arm_models/armv4txm
www.systemc-processor-models.org has the page www.systemc-processor-models.org/arm_models/armv4txm
www.systemc-tlm-models-library.org has the page www.systemc-tlm-models-library.org/arm_models/armv4txm
www.imperas.com has more information on the model library
http://www.ovpworld.org: Creating Instruction Accurate Processor models using the VMI API
http://www.ovpworld.org: Debugging with Imperas eGui running on OVP platforms
Currently available Fast Processor Model Families.