Architectures and Processors

ARM Helium (CM85) Transpose Intrinsic Absence Compared to Neon The ARM Cortex-M85 processor, equipped with the Helium (M-Profile Vector Extension, MVE) instruction set, introduces significant enhancements for vector processing compared to its predecessors. However, developers transitioning from Neon-based architectures (e.g., Cortex-A series) to Helium may encounter challenges due to differences in intrinsic support. One such…

ARM BP210 Bus Matrix Address Overlap Errors During Master-Slave Configuration When configuring the ARM BP210 bus matrix using ARM Socrates, a common issue arises when attempting to define shared address mappings for multiple masters accessing the same slave. Specifically, the error message "Interface SI1 address region ‘MI3: A0000000-AFFFFFFF’ overlaps with another address region ‘MI0: A0000000-AFFFFFFF’"…

Debug Logs Not Displaying in Serial Viewer During Debug Mode When working with a Cortex-M0 microcontroller in KEIL uVision 5, one of the most common issues developers face is the inability to view debug logs transmitted via UART1 in a serial viewer while in debug mode. This issue can stem from a variety of factors,…

ARM64 NEON SIMD as a Replacement for SSE4.2 in CNDP The Cloud Native Data Plane (CNDP) project is a high-performance, user-space library designed to accelerate packet processing for cloud-native applications. Originally developed for x86_64 architectures, CNDP relies heavily on Intel’s SSE4.2 instruction set for SIMD (Single Instruction, Multiple Data) operations, which are critical for achieving…

ARM Cortex-R52 PMHF Calculation and Unit Clarification The Probabilistic Metric for Hardware Failure (PMHF) is a critical metric in Functional Safety analysis, particularly when evaluating the reliability of systems designed to meet ISO 26262 or similar safety standards. In the context of the ARM Cortex-R52 processor, PMHF is used to quantify the likelihood of random…

ARMv7-M HardFault Triggered by Instruction Access Violation During Signal Handler Execution The core issue revolves around a HardFault occurring when returning from a memory fault (MemFault) handler and attempting to execute a signal handler in an ARMv7-M architecture. The fault manifests as an instruction access violation (CFAULT = 0x1) with a "FORCED" HardFault (HFAULT =…

ARM Cortex-M23 TrustZone Initialization and SAU Configuration Problems The ARM Cortex-M23 processor, designed for embedded systems requiring robust security, incorporates ARM TrustZone technology to create a secure and non-secure (NS) execution environment. TrustZone enables the partitioning of memory and peripherals into secure and non-secure regions, managed by the Security Attribution Unit (SAU) and System Control…

Cortex-M33 Unprivileged Mode Stack Corruption and Register Zeroing in Secure State When running an unprivileged application in the secure state on the Cortex-M33 processor (specifically on the STM32U5 microcontroller with TrustZone enabled), a critical issue arises. The system exhibits unexpected behavior during context switching and exception handling. Specifically, when the Link Register (LR) is set…

DSU CHI Interface Coherency and Link Deactivation Overview The DynamIQ Shared Unit (DSU) is a critical component in ARM-based systems, particularly when connected to an interconnect via the Coherent Hub Interface (CHI). The DSU acts as a master interface, managing coherency and communication between multiple cores, caches, and the interconnect. A key aspect of the…

ARM Cortex Cache Line Faults and Their Impact on System Reliability Cache memory in ARM processors is a critical component that significantly impacts system performance and reliability. However, like any other hardware component, cache memory is susceptible to manufacturing defects, aging, or environmental factors that can introduce faulty bits. These faulty bits, often referred to…