MMU Translation Faults During DDR ECC Error Handling in Abort Mode The core issue revolves around MMU translation faults occurring during the handling of DDR ECC uncorrectable errors in an ARM Cortex-A9 dual-core system. The system is designed to handle Data Abort and Prefetch Abort exceptions, specifically targeting asynchronous external memory aborts triggered by DDR…
Systick Handler Triggered Due to Missing or Incorrect Systick ISR Implementation The core issue revolves around the Systick handler being triggered unexpectedly during the setup of a delay timer on an STM32F407 Discovery board. The user is attempting to create a simple blinking LED program but encounters a Systick_Handler interrupt, which indicates a problem with…
ARM Trusted Firmware Bootloader Setup for Cortex-A53 Without U-Boot The process of configuring the ARM Trusted Firmware (ATF) as a bootloader for the Cortex-A53 processor on the i.MX8QM EVK involves several critical steps. The primary goal is to boot the system using only the ATF (specifically the BL31 binary) without relying on U-Boot. This setup…
ARMv8-A AArch64 Instruction Syntax Errors in DS5 When working with ARMv8-A AArch64 assembly code in the DS5 (ARM Development Studio 5) simulation environment, developers may encounter syntax errors related to the use of the UMOV and INS instructions. Specifically, errors such as "unknown token in expression" and "unexpected token in argument list" can occur when…
Outdated ARM AArch64 Programmer’s Guide and Missing Modern Documentation The ARM AArch64 architecture, part of the ARMv8-A and ARMv9-A families, is a powerful and widely used 64-bit instruction set architecture (ISA) that powers everything from mobile devices to servers. However, developers working with AArch64 often face challenges due to outdated or incomplete documentation. The primary…
ARM Cortex-A78 L1 Cache: VIPT Behaves as PIPT The ARM Cortex-A78 employs a sophisticated cache architecture where the L1 cache operates under a Virtual Index Physical Tag (VIPT) scheme but behaves like a Physically Indexed Physically Tagged (PIPT) cache. This unique behavior is crucial for understanding how the Cortex-A78 manages memory accesses efficiently while avoiding…
ARM Cortex-M0+ Shift Operations with Register-Based Shift Values The ARM Cortex-M0+ processor, as a member of the ARMv6-M architecture, implements a subset of the Thumb instruction set. One of the key features of this architecture is its support for shift operations, which are commonly used in embedded systems for data manipulation, bitwise operations, and performance…
ARM Cortex-M I2CMDR Register Update Failure During I2C Debugging The I2CMDR register in ARM Cortex-M microcontrollers is a critical component for managing I2C communication. When the I2CMDR register fails to update, it can halt I2C operations, leading to communication failures between the microcontroller and peripheral devices. This issue is particularly problematic during debugging sessions, where…
Heterogeneous Multi-Core Boot Process and Independence Challenges In modern embedded systems, heterogeneous multi-core processors, such as those combining ARM Cortex-A53 and Cortex-M7 cores, are increasingly common. These architectures leverage the strengths of both application-class cores (Cortex-A53) and microcontroller-class cores (Cortex-M7) to deliver high performance and real-time capabilities. However, booting these cores independently, especially when running…
ARM Cortex-A55 Invalidate Queue and Cache Coherency Mechanisms The ARM Cortex-A55 is a high-efficiency processor core designed for use in symmetric multiprocessing (SMP) systems. One of the critical aspects of SMP systems is ensuring cache coherency across multiple cores. The Cortex-A55 implements a cache coherency mechanism that includes features such as the invalidate queue, which…