The Field Programmable Gate Array (FPGA) is Xilinx’s core product line. It is a semiconductor device that can be programmed and reprogrammed after production. FPGAs are helpful in various applications such as aerospace and military, automotive, industrial automation, data center and networking, and wired and wireless communications.
In addition to FPGAs, Xilinx provides design and development software tools, including the Vivado Design Suite, the SDx Development Environment, and the PetaLinux Tools. IP cores from the firm perform various functions, including connection, memory interfaces, video and image processing, and security.
Xilinx Versal is an ACAP family that integrates the capabilities of CPUs, GPUs, DSPs, and programmable logic in a single device. Versal should meet next-generation applications’ high performance and power efficiency requirements in the data centre, 5G wireless, and automotive sectors.
Versal devices depend on a novel architecture known as the “Adaptive Compute Acceleration Platform” (ACAP), which is a cross between an FPGA and a system-on-chip (SoC). The ACAP combines the programmability and flexibility of an FPGA with the integration and simplicity of use of an SoC, allowing designers to create unique hardware accelerators and adapt systems to their specific requirements.
Versal devices come in various sizes and configurations to satisfy the demands of various applications. Devices in the series have up to 9 million system logic cells, 6,840 DSP engines, and 8,520 AI engines. Versal also supports a variety of high-speed connections, including PCIe Gen 5 and DDR5.
The Vitis development environment, the Vivado design suite, and the Xilinx runtime library are among the software tools produced by Xilinx to aid in creating Versal-based systems (XRT). In addition, the business provides a variety of IP cores for use with Versal, including networking, video and image processing, and machine learning.
The design process for Xilinx Versal
System-on-chips (SoCs) like the Xilinx Versal combine several forms of programmable logic, CPU cores, memory, and other IP blocks onto a single chip. Architecture definition, system-level design, IP integration, functional verification, timing analysis, and physical design are some stages of the Xilinx Versal design process. We will go through each step in depth in this post, as well as some difficulties and best practices for designing Xilinx Versal.
Defining the system’s architecture is the initial step in the design process. This entails evaluating the system’s requirements and specifications, choosing the proper CPU cores, programmable logic, memory, and other IP blocks, and figuring out how to connect these elements. When defining the architecture, performance, power consumption, size, and system cost should all be considered.
Developing a high-level system block diagram that illustrates the links between the various IP blocks is known as the system-level design stage. This diagram serves as the overall design’s blueprint and aids in locating any potential performance problems or bottlenecks. At this stage, designers must also consider how the system will fall into various zones and how data will move among them.
Once the system-level design is complete, designers can begin incorporating the various IP blocks into the design. To accomplish this, the IP blocks must conform to the system’s specifications, connect to the proper interfaces, and test for functionality. Managing the design’s complexity at this point is one of the significant difficulties because there may be hundreds or even thousands of IP blocks to integrate.
The process of ensuring the system operates as anticipated and satisfies design requirements is known as functional verification. Test benches that imitate the system’s behavior under various circumstances must be ready to do this. Additionally, we must confirm the accuracy of the results. Functional verification is a crucial step in the design process since it assures that the system will operate as intended and helps identify any design flaws early on.
Making sure that the design complies with the system’s timing requirements is done through timing analysis. This entails inspecting the timing connections between various IP blocks to check that the setup, hold periods, and clock frequencies are within the permitted range. Timing analysis is crucial because functional problems or decreased system performance may emerge if the design doesn’t adhere to the timing specifications.
Physical design, the last stage of the design process, entails putting the design onto silicon. This entails laying out the chip in great detail, planning the routing and positioning of the various IP blocks, and running several checks to ensure the design complies with production standards. In addition, physical design requires balancing performance, power consumption, and chip size, which is a difficult and time-consuming procedure.
Challenges and Best Practices
Xilinx Versal design involves several problems, such as controlling design complexity, ensuring the system fulfills performance and power requirements, and reducing design time and cost. However, designers can adhere to the following best practices to overcome these difficulties:
Use a top-down design approach:
Starting with a high-level system design, this method entails improving the design at each procedure stage. This strategy reduces the possibility of design errors while ensuring the system satisfies the requirements.
Reuse IP blocks:
Various IP blocks that can be helpful in various designs are in Xilinx Versal. Reusing IP blocks can minimize design complexity and save time.
Use simulation and emulation tools:
Design flaws are available early in the process before implementing the design in silicon, with simulation and emulation tools. These tools can also test the system’s performance and functionality in various scenarios.
Perform thorough functional verification:
A crucial step in the design process, functional verification helps ensure the system operates as intended and meets design requirements. Designers should develop thorough test benches for all potential scenarios and edge cases.
Optimize power consumption:
Dynamic voltage and frequency scaling, power gating, and other capabilities for power optimization are all included in Xilinx Versal. These characteristics should incorporate into designs to reduce system power usage.
Pay attention to timing closure:
One of the most challenging parts of the design process is timing closure. To ensure the design satisfies the system’s timing requirements, designers should employ timing analysis tools and use methods like clock domain crossing and pipelining to shorten the time routes.
Use good design practices:
Designers should adhere to sound design principles, including modular design, appropriate naming conventions, and code commenting. This could enhance the design’s readability, maintainability, and reusability.
Collaborate with other designers:
Creating Xilinx Versal is a difficult, multidisciplinary task requiring various skills. For example, to ensure that the design satisfies the requirements and is error-free, designers should work with other designers, system architects, and verification engineers.
Finally, designing Xilinx Versal necessitates a strict and organized methodology that includes several steps, from architecture specification to physical design. Nevertheless, by adhering to best practices, designers can overcome obstacles and produce high-quality designs that satisfy the system’s performance, power, and cost requirements.
Xilinx Versal Architecture
Xilinx Versal is a fantastic platform that you can use to create custom hardware accelerators for all kinds of applications. It combines the power and flexibility of FPGAs with the ease and integration of a system-on-chip. The platform depends on adaptive compute acceleration (ACAP), which has many processing engines like CPUs, DSPs, and programmable logic, all connected to a high-speed network. This allows you to build specialized hardware accelerators with excellent performance, low latency, and low power consumption. Plus, it’s flexible and can adjust to changing workloads through software-controlled engines and programmable logic. The three main components are the processor subsystem, the programmable logic subsystem, and the platform management subsystem.
The processing subsystem comprises several processing engines, such as Arm Cortex-A72 application processors, Arm Cortex-R5 real-time processors, Mali graphics processors, and other digital signal processors (DSPs). The NoC connects these engines and may cooperate in carrying out challenging tasks. Other peripheral interfaces included in the processor subsystem include Ethernet, USB, PCIe, and DDR memory.
One of its main characteristics is the processing subsystem’s capacity to assign resources following the workload dynamically. Hardware accelerators and processing engines controlled by software work together to accomplish this. Software-controlled processing engines may be flexibly assigned to various tasks as needed. In contrast, hardware accelerators are designed to utilize the programmable logic subsystem and can tune specific tasks.
Programmable Logic Subsystem
The Xilinx Versal Programmable Logic Subsystem will hasten the creation and implementation of AI and other high-performance computing applications. It sits on the Versal Adaptive Compute Acceleration Platform (ACAP). It combines high-speed interconnects, sophisticated networking, and security features with programmable circuitry, software-programmable computation, and memory.
The Programmable Logic Subsystem offers a highly programmable and scalable platform. It allows programmers to balance performance, cost, and power consumption for particular application requirements. With high-speed serial transceivers and programmable I/O interfaces, it also contains various programmable logic resources, including programmable logic blocks, DSP slices, and memory blocks.
The Versal ACAP platform offers a variety of software tools and libraries. As a result, they speed up application development and deployment in addition to their hardware capabilities. These include the AI Engine software development kit. It also offers a unified software development flow for the processing and programmable logic subsystems.
Platform Management Subsystem
In Xilinx Versal, the platform management subsystem oversees the entire system, including power management, security, and system-level operations. A security processing unit (SPU), a system management unit (SMU), and a power management unit are some of the various parts that make up the platform management subsystem (PMU).
Security Processing Unit (SPU)
The hardware component designated as the security processing unit (SPU) is in charge of putting hardware-based security features into action. Several security capabilities, including as secure boot, safe key storage, and secure firmware upgrades, are offered by the SPU. In addition, the SPU is segregated from the rest of the system to avoid unwanted access and can offer a secure foundation for the entire system.
A crucial security feature offered by the SPU is a secure boot. The secure boot ensures that only trusted software is loaded during the boot process to prevent malware or other unauthorized code from running on the system. As the firmware and software components load throughout the boot process, the SPU stores a chain of trust that confirms their reliability and integrity. In addition, the boot process is interrupted, stopping the system from starting if any component fails verification.
For the secure key storage of cryptographic keys needed for encryption and authentication, the SPU is also available. To safely store keys and restrict illegal access, the SPU employs specialized hardware-based key management. This ensures that private keys and other critical information are safe from hackers.
To ensure that the system is running the most recent, safe firmware, the SPU also offers secure firmware updates. In addition, the SPU prevents hackers from tampering with the firmware by downloading and verifying firmware updates through a secure channel.
System Management Unit (SMU)
The system management unit oversees system-level activities for the Xilinx Versal device (SMU). The SMU provides a variety of system-level functionalities, including power management, thermal management, and system monitoring.
The main function of the SMU is power management. The SMU is in charge of managing the system’s power consumption and ensuring that electricity is supplied to the various components most efficiently. Power-saving techniques used by the SMU include clock gating, power gating, and dynamic voltage and frequency scaling (DVFS).
Thermal control is yet another crucial capability made available by the SMU. The device’s temperature undergoes monitoring by the SMU. It is also responsible for ensuring that it maintains within acceptable working ranges. Several techniques, such as fan control, dynamic clock frequency adjustment, and thermal throttling, are essential for the SMU to regulate the temperature.
System monitoring is another essential capability provided by the SMU. The system’s health and state, including voltage, temperature, and clock frequency, are monitored by the SMU. Among the monitoring interfaces the SMU provides for system administrators to keep a watch on and manage the system are JTAG, SMBus, and IPMI.
Comparison of Xilinx Versal to previous Xilinx architectures
The most recent Xilinx architecture, Xilinx Versal, marks a substantial change from earlier Xilinx architectures. The following are some essential distinctions between Xilinx Versal and earlier Xilinx architectures:
The degree of integration is among the greatest distinctions between Xilinx Versal and earlier Xilinx systems. Xilinx Versal will fully integrate as a platform combining several processing units, programmable logic, memory, and IO into one unit. Earlier Xilinx architectures, in contrast, relied on separate devices for processing and programmable logic, necessitating more complex system designs and using more power.
Versal will have greater flexibility than earlier Xilinx architectures. It is simpler to integrate with many systems since it supports a wide range of I/O standards, memory interfaces, and connectivity options. Moreover, it offers the dynamic function eXchange (DFX). This feature enables a single device to change to meet changing needs by, for example, adding or removing processing cores as necessary.
Lower Power Consumption:
Versal focuses on power efficiency. It has various features like sophisticated power management, improved voltage control, and adaptive power scaling that reduce power usage without sacrificing performance.
Versal offers much greater performance compared to earlier Xilinx architectures. It can manage to demand compute-intensive applications, high-speed networking, and complicated AI/ML workloads. Performance-enhancing features include protected compute engines, high-speed interconnects, and high-bandwidth memory.
Integrated System-on-Chip (SoC) Capabilities:
Versal combines conventional FPGA fabric with additional on-chip elements. They include Arm processor cores, memory, and communication, to create integrated system-on-chip (SoC) capabilities. Its integration improves efficiency and makes constructing systems that need processing cores and programmable logic simpler.
Ethernet, PCIe Gen4, and CCIX are just a few of the high-speed connectivity options Xilinx Versal offers. Due to its ability to connect quickly to many peripherals and other devices, the platform is helpful for various applications.
Overall, Xilinx Versal is an appealing option for developers and system designers since it is a highly adaptable platform with excellent performance across various applications and workloads.