Author: System on Chips

Standard C Library Functions Execution in External Flash Causing Performance Bottlenecks In ARM-based SoC designs, the execution of standard C library functions such as memcpy, sin, and others in external flash memory can lead to significant performance degradation. This is primarily due to the slower access times and higher latency associated with external flash compared…

AMBA AHB Lite Four-Beat Wrapping Burst Address Sequence Anomaly The AMBA AHB Lite protocol is widely used in ARM-based SoC designs for its simplicity and efficiency in handling data transfers between masters and slaves. One of the key features of AHB Lite is its support for burst transfers, which allow multiple data transactions to occur…

Understanding the fclk and tck Clock Domains in ARM SoCs In ARM-based System-on-Chip (SoC) designs, clock domain crossing (CDC) between functional clocks (fclk) and test clocks (tck) is a critical aspect of timing closure and functional correctness. The fclk domain typically operates at the system’s functional frequency, while the tck domain is used for test…

ACE Snoop Transactions and Cache Coherency in ARM-Based SoCs In ARM-based SoCs, the Advanced Extensible Interface (AXI) Coherency Extensions (ACE) protocol plays a critical role in maintaining cache coherency across multiple masters and shared memory regions. ACE snoop transactions are a fundamental mechanism for ensuring that all caches in the system have a consistent view…

NiC-400 Read/Write Acceptance Configuration and FIFO Allocation The NiC-400 interconnect is a highly configurable and scalable interconnect IP from ARM, designed to facilitate efficient communication between multiple initiators and targets in an ARM-based SoC. One of the key features of the NiC-400 is its ability to manage read and write transactions with configurable acceptance and…

SystemC Library and Application C++ Standard Version Conflict The core issue revolves around a mismatch between the C++ standard used to compile the SystemC library provided with ARM Fast Models v11.15 and the C++ standard used to compile the consumer application. The SystemC library in Fast Models v11.15 is compiled with C++11 support, while the…

CHI Protocol Data Packetization Rules and Bus Width Impact The ARM Coherent Hub Interface (CHI) protocol is a critical component in modern ARM-based SoCs, enabling efficient communication between agents in a coherent system. One of the key aspects of CHI is its data packetization mechanism, which determines how data is segmented and transmitted across the…

CHI Read Data Packet Handling in Device Memory Transactions In ARM’s Coherent Hub Interface (CHI) protocol, handling read data packets for Device Memory type transactions can present unique challenges, particularly when the returned data size does not match the expected transaction size. This issue arises because Device Memory transactions do not support byte-level enables for…

ARM CHI Protocol: Device Memory Type Transactions and Narrow Read Transfers The ARM Coherent Hub Interface (CHI) protocol is a critical component in modern ARM-based SoC designs, enabling efficient communication between various system components such as CPUs, GPUs, and memory controllers. One of the key features of CHI is its support for different memory types,…

AXI Slave Behavior with Illegal Write Strobes: Protocol Ambiguity and System Impact The Advanced eXtensible Interface (AXI) protocol, widely used in ARM-based SoCs, defines a robust framework for high-performance on-chip communication. However, the protocol does not explicitly mandate how an AXI slave should handle illegal write strobes (WSTRB). This ambiguity can lead to inconsistent behavior…