Most of the development of my µOS++ / CMSIS++ RTOS was done on GNU ARM Eclipse QEMU and/or as a 64-bits user process on macOS.
However, on QEMU, initially I encountered some strange behaviour when configuring the critical sections to use BASEPRI; when using DI/EI everything was fine. These days I took some time to investigate the problem and discovered that the BASEPRI register was not used by the NVIC implementation, so implementing critical sections with BASEPRI was not effective in QEMU. Since the current NVIC implementation is a kludge running on top of GIC, and I still have on my TOOD list to completely rewrite the NVIC code, for now I just further patched the current patches in order to make it work. If someone is planing to properly implement BASEPRI in QEMU, my patches can be used as a starting point. (https://github.com/gnuarmeclipse/qemu/issues/21) Please note that by default FreeRTOS uses BASEPRI in the Cortex-M3/M4/M7 ports, so don't bother to run them on the current QEMU, or you'll encounter problems. The next release of GNU ARM Eclipse QEMU will be fine. Regards, Liviu
