April 2026 monthly summary focusing on the FRDM-RW612 flash controller devicetree fix in Zephyr; completed a critical bug fix that restores correct hardware initialization and improves reliability across the FRDM-RW612 setup.

March 2026 highlights for zephyr project: Delivered foundational NAND storage capabilities on FRDM-RW612 with NXP FlexSPI and enhanced runtime flexibility for storage hardware, while expanding CI coverage and sample implementations. The work emphasizes business value by enabling robust, scalable storage options for embedded targets and improving resilience in non-initialized or constrained environments. Key outcomes: 1) NAND flash support and LittleFS integration on FRDM-RW612 with NXP FlexSPI: Implemented ONFI NAND support via device-tree bindings, added a SPI-NAND driver with ONFI parameter page probing and bad-block management, added Winbond W25N01GV support, and enabled LittleFS FTL on NAND. A CI build/test scenario was introduced for W25N01GV to validate end-to-end functionality. 2) Runtime FlexSPI configuration APIs and LUT updates: Added APIs to configure FlexSPI port pins and to update the LUT at runtime, improving support for non-initialized systems (XIP scenarios) and interrupt handling. Included safeguards to minimize latency in non-XIP environments. Major bugs fixed / robustness improvements: - Hardened runtime behavior for non-XIP systems by guarding irq_lock() calls with CONFIG_FLASH_MCUX_FLEXSPI_XIP to avoid unnecessary interrupt latency. - Stabilized runtime LUT updates by using a stack buffer to avoid XIP pointer rejection, reducing edge-case failure modes during dynamic configuration. - Ensured safe enablement of NAND device nodes with a default-disabled W25N01GV entry, preventing unintended hardware configuration during boot. Overall impact and accomplishments: - Expanded storage capabilities for embedded targets, enabling reliable NAND + LittleFS usage and dynamic memory controller configuration. - Improved reliability and performance in storage-related boot paths and runtime configuration, improving time-to-market for features requiring NAND-backed storage. - Strengthened development workflow with CI coverage for NAND scenarios and practical samples (LittleFS over Dhara FTL on NAND). Technologies and skills demonstrated: - Device-tree bindings and kernel driver development for NAND on NXP FlexSPI (ONFI), including bad-block management. - NAND geometry probing at runtime, and integration of LittleFS as a FTL-backed backend. - Runtime hardware configuration via FlexSPI APIs (pinctrl, LUT), with careful handling for XIP/non-XIP scenarios and interrupt latency considerations. - Testing, CI scenario creation, and sample/documentation updates to support NAND-enabled workflows.

2025-11 Monthly Summary for nrfconnect/sdk-zephyr: - Key feature delivered: XIP mode device configuration reliability achieved by adding a bus idle wait after clock rate query to ensure AHB transactions complete before device configuration. This enables XSPI_SetDeviceConfig to succeed in XIP environments. - Major bugs fixed: XIP mode device config failure caused by asynchronous AHB activity during clock rate queries; the bus idle wait prevents XSPI_SetDeviceConfig from failing due to ongoing AHB access detection. - Impact: Higher reliability of XIP boot/config paths, reduced field failures and troubleshooting time in XIP deployments; improved test stability for XIP scenarios. - Technologies/skills demonstrated: Zephyr kernel driver development (SPI/XSPI), C, clock control integration, AHB/bus timing considerations, debugging of asynchronous hardware interactions, and disciplined commit-based development.

Monthly work summary for 2025-09: Focused on stabilizing XSPI cache operations in hal_nxp. Delivered a critical bug fix and improved cache reliability, contributing to data integrity in XSPI paths and overall system stability.

August 2025 monthly summary focused on enabling XSPI external memory support for the NXP RT700 in the Zephyr repository. Work emphasizes hardware-software integration, cross-core enablement, and board-level configuration to unlock external memory capacity and performance.

December 2024: Delivered RTWDOG driver support in mcux HAL for RT1180 and stabilized watchdog operation. Implemented a synchronization fix to prevent race conditions and updated the README to ensure proper RTWDOG usage. These changes enhance reliability of the watchdog peripheral and reduce configuration errors, enabling smoother deployments and lower maintenance costs.