ARM Cortex-M4 BusFault on Power Reset Due to Invalid Memory Access

ARM Cortex-M4 BusFault on Power Reset Due to Invalid Memory Access

BusFault Triggered by Invalid Pointer Dereference During System Initialization The core issue revolves around a BusFault occurring during system power-up, specifically when dereferencing a pointer (*pp_data) in the function uarte_get_async_data. The fault manifests as an access to an invalid memory address (0x0601235d), which is not a valid memory location for the system. This fault is…

ARM Cortex-A53 Bare Metal Optimization: NEON, FPU, and GCC Compiler Flags

ARM Cortex-A53 Bare Metal Optimization: NEON, FPU, and GCC Compiler Flags

ARM Cortex-A53 NEON and FPU Optimization Challenges with GCC The ARM Cortex-A53 is a widely used 64-bit processor core that is part of the ARMv8-A architecture. It is commonly employed in embedded systems and applications requiring high efficiency and performance. One of the key features of the Cortex-A53 is its support for Advanced SIMD (NEON)…

Running Linux on Cortex-M MCU in STM32MP157: Debugging __free_pages_bootmem Failure

Running Linux on Cortex-M MCU in STM32MP157: Debugging __free_pages_bootmem Failure

ARM Cortex-M Linux Kernel Boot Failure in STM32MP157 The core issue revolves around attempting to run a Linux kernel on a Cortex-M microcontroller within the STM32MP157 evaluation board, specifically encountering a failure in the __free_pages_bootmem function during kernel initialization. This function is part of the Linux kernel’s memory management subsystem, responsible for freeing pages allocated…

ARM Cortex-M4 Cross-Compiler Memory Allocation Error During Large File Compilation

ARM Cortex-M4 Cross-Compiler Memory Allocation Error During Large File Compilation

ARM Cortex-M4 Cross-Compiler Memory Allocation Error During Large File Compilation When working with embedded systems, particularly those based on ARM Cortex-M4 processors, developers often rely on cross-compilers to translate high-level code into machine code that can be executed on the target hardware. One common issue that arises during this process is the "out of memory"…

Cortex-A53 Bare Metal Booting FIQ Exception Debugging Guide

Cortex-A53 Bare Metal Booting FIQ Exception Debugging Guide

Cortex-A53 FIQ Exception During Bare Metal Boot in init_libc When booting a Cortex-A53 processor in bare metal mode, a Fast Interrupt Request (FIQ) exception can occur during the execution of the init_libc function. This issue is particularly prevalent when using the GCC Linaro 4.9 toolchain with glibc 2.14. The FIQ exception is triggered unexpectedly, leading…

ARM Cortex-A7 Thumb-2 Library Usage with -marm Compilation Flag

ARM Cortex-A7 Thumb-2 Library Usage with -marm Compilation Flag

ARM Cortex-A7 Library Selection Mismatch with -marm Compilation Flag When compiling for the ARM Cortex-A7 processor using the -marm flag, which instructs the compiler to generate ARM (32-bit) instructions, developers may encounter an unexpected behavior where the -print-libgcc-file-name option returns a Thumb-2 library path instead of an ARM library. This discrepancy arises because the GNU…

ARM Cortex-M Switching from SYSTEM to USER Mode: Stack Initialization and Mode Transition Issues

ARM Cortex-M Switching from SYSTEM to USER Mode: Stack Initialization and Mode Transition Issues

ARM Cortex-M USER Mode Transition Failure Due to Improper CPSR Handling The core issue revolves around the inability to successfully transition from SYSTEM mode to USER mode on an ARM Cortex-M processor. The user has configured the stack pointers for both SYSTEM and USER modes in the linker script and attempted to switch modes using…

ARM Cortex-A9 L2 Cache Parity Errors During Level-2 MMU Page Walks

ARM Cortex-A9 L2 Cache Parity Errors During Level-2 MMU Page Walks

ARM Cortex-A9 L2 Cache Parity Errors During Level-2 MMU Page Walks The ARM Cortex-A9 processor, integrated with an ARM PL310 L2 cache controller, is a widely used architecture in embedded systems. However, a critical issue arises when dealing with L2 cache parity errors during Level-2 MMU page walks. This issue manifests as synchronous aborts triggered…

ARM Cortex-M4 FPB Breakpoint Configuration Without Debugger

ARM Cortex-M4 FPB Breakpoint Configuration Without Debugger

DebugMon Handler Not Triggering Despite FPB Configuration The issue revolves around the inability to trigger the DebugMon handler on an ARM Cortex-M4 processor when attempting to set a breakpoint programmatically using the Flash Patch and Breakpoint (FPB) unit. The goal is to configure the FPB to trigger a breakpoint when a specific instruction address is…

ARM Cortex-A35 Cache Coherency and System-Wide Flush for Multi-Core Systems

ARM Cortex-A35 Cache Coherency and System-Wide Flush for Multi-Core Systems

Cache Coherency Challenges in Multi-Core ARM Cortex-A35 Systems In multi-core ARM Cortex-A35 systems, such as the i.MX8DX platform, cache coherency is a critical aspect of ensuring data integrity and consistency across cores. The Cortex-A35 cores (Core 0 and Core 1) share a common L2 cache but maintain separate L1 caches. This architecture introduces complexities when…