Detailed introduction of SoC FPGA, including Xilinx and Altera product series
There are various definitions of SoC. Because of its rich connotation and wide application range, it is difficult to give an accurate definition. Generally speaking, SoC is called a system-level chip, also called system-on-chip, which means that it is a product, an integrated circuit with a dedicated target, which contains a complete system and all the contents of embedded software. At the same time, it is a kind of technology to realize the whole process from determining the system function to dividing the software/hardware and completing the design.
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Intel Cyclone V SoC FPGA is a new SoC chip released by Intel PSG (formerly Altera) in 2013 that integrates dual-core ARM Cortex-A9 processor and FPGA logic resources on a single chip. Compared with the traditional single ARM processing Intel Cyclone V SoCFPGA not only has the flexible and efficient data computing and transaction processing capabilities of the ARM processor but also integrates the high-speed parallel processing advantages of FPGA.
At the same time, based on the unique on-chip interconnect structure of the two, it can be used The general logic resources on the FPGA are configured and mapped to one or more peripherals with specific functions of the ARM processor, and communicate through the AXI high-speed bus up to 128 bits wide to complete the interaction of data and control commands. Because the on-chip ARM processor is hard-wired logic that has been placed and routed, the clock frequency that it can work on is higher, so more instructions can be executed per unit time.
Before the introduction of SoC FPGA technology, major FPGA manufacturers had promoted SOPC technology for many years. Unlike SoC FPGA, SOPC uses FPGA logic and memory resources to build a soft-core CPU system on a pure FPGA chip, and the soft-core CPU realizes the complete functions of the required processor. Because it is a CPU built with the general logic of FPGA, it has a certain degree of flexibility. Users can customize the CPU according to their own needs and add some special functions, such as division or floating-point arithmetic units, to improve the CPU Dedicated computing performance, or delete some functions that are not used in the system to save logic resources.
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In addition, according to the actual needs of users, various standard or customized peripherals can be added to the CPU, such as standard interface peripherals such as UART, SPI, IIC, etc. At the same time, users can also use FPGA logic resources to write various dedicated Peripherals that are then connected to the CPU bus and controlled by the CPU to realize the cooperative work of software and hardware, which increases the flexibility of the system while ensuring system performance. Moreover, if a single soft-core CPU cannot meet user needs, you can add multiple CPU soft-cores to build a multi-core system, and the multi-core CPU can work together to give the system more flexible and convenient control capabilities.
SoC has two notable features: one is the large-scale hardware, which is usually based on the IP design model; the other is that the software has a large proportion and requires software and hardware co-design. Compared with rural areas, cities have obvious advantages: complete facilities, convenient transportation, and high efficiency. SoC also has similar characteristics: more supporting circuits are integrated on a single chip, which saves the area of integrated circuits and also saves costs, which is equivalent to improved energy efficiency in cities; on-chip interconnection is equivalent to urban expressways and high-speed, Low power consumption, the information transmission between the various devices originally distributed on the circuit board is concentrated in the same chip, which is equivalent to a place that could only be reached by a long-distance bus. Now it has moved to the city. Take a trip The subway or BRT is here, which is obviously much faster; the city's tertiary industry is developed and more competitive, and the software on the SoC is equivalent to the city's service business. Not only is the hardware good, but the software is also good; the same set of hardware It can be used to do something today, and it can be used to do another thing tomorrow, which is similar to the improvement of resource allocation, scheduling and utilization of the entire society in the city. It can be seen that SoC has obvious advantages in terms of performance, cost, power consumption, reliability, and life cycle and scope of application, so it is an inevitable trend in the development of integrated circuit design.
At present, SoC has occupied a dominant position in the field of terminal chips that are sensitive to performance and power consumption; and its application is expanding to a wider area. The realization of a complete electronic system on a single chip is the future development direction of the IC industry.
However, because the CPU is built using the general logic resources of FPGA, compared to using a hard-core processor optimized for placement and routing, the highest real clock frequency that a soft-core processor can run is lower, and it will also respond accordingly. Consumes more FPGA logic resources and on-chip memory resources, so the SOPC solution is only suitable for applications that do not require high overall performance of the digital processor, such as the initial configuration of the entire system, human-computer interaction, coordinated control between multiple functional modules, etc. Features.
Xilinx SoC FPGA series
Xilinx Defense-grade Zynq-7000Q SoC
ALTERA SoC FPGA series