Architectures and Processors

AXI FIXED Burst WSTRB Calculation and Lane Alignment Issues In AXI4 FIXED burst type transactions, the calculation of the write strobe (WSTRB) and the alignment of byte lanes can be a source of confusion, especially when dealing with unaligned start addresses. The WSTRB signal is critical in AXI transactions as it indicates which byte lanes…

ARM Coresight Architecture: ROM Table Integration Complexity The integration of AHB ROM tables into the Coresight system ROM table presents a multifaceted challenge in ARM-based SoC designs. The Coresight architecture, a critical component for debugging and tracing, relies on a hierarchical system of ROM tables to identify and access various debug components. These ROM tables…

CoreSight STM and TPIU Driver Integration Failures in R8A77970 SoC The integration of CoreSight STM (System Trace Macrocell) and TPIU (Trace Port Interface Unit) drivers in the Renesas R8A77970 SoC is encountering significant issues due to missing device tree source (DTS) entries. The absence of critical components such as STM, STM500, ETM4.0, Funnel, Replicator, TMC-ETR,…

ARM-A15 Program Counter and AXI Traffic Debugging Challenges in VCS Simulation When integrating an ARM Cortex-A15 processor into a System-on-Chip (SoC) design, one of the most critical aspects of verification is ensuring visibility into the processor’s execution flow and its interaction with the system via the AXI bus. The Program Counter (PC) is a fundamental…

ARM DS-5 Linux Project Executable Naming and Extension Inconsistencies When working with ARM DS-5 for Linux project development, one of the common issues that developers encounter is the inconsistency in the naming and extension of the generated executable files. Specifically, some projects generate executables with the .axf extension, while others do not. This inconsistency can…

AXI4 Unaligned Transfer Confusion: Aligned Address vs. Unaligned Address with WSTRB The AXI4 protocol provides flexibility for handling unaligned transfers, but the specification’s phrasing regarding the relationship between the address and write strobes (WSTRB) can lead to confusion. Specifically, the protocol states that a master can either use the low-order address lines to signal an…

Understanding the Role of Assertions in APB4 Protocol Verification Assertions in the context of APB4 protocol verification serve as formal checks that ensure the design adheres to the protocol specifications. These assertions are typically written in SystemVerilog Assertions (SVA) and are embedded within the protocol checker module. The primary purpose of these assertions is to…

ARM M1 DesignStart FPGA Integration with Nexys4 DDR The integration of the ARM M1 DesignStart FPGA on the Nexys4 DDR board presents a unique set of challenges, particularly when transitioning from the ARTY A7 board, which is commonly used in tutorials and documentation. The primary issue revolves around the adaptation of the hardware system and…

ARM CHI Protocol Cache Line State Transitions and Their Significance The ARM Coherent Hub Interface (CHI) protocol introduces two additional cache line states compared to the AXI protocol: Unique Clean Empty (UCE) and Unique Dirty Partial (UDP). These states are critical for optimizing cache coherency, reducing unnecessary data transfers, and improving system performance in complex…

ARM SoC Data Link Layer to Command+Data Exchange Conversion Challenges In ARM-based SoC designs, one of the critical tasks during verification is processing raw data captured from monitors at the data link layer and converting it into a structured set of commands and data exchanges at a higher abstraction level. This conversion is essential for…