bsg_newlib_dramfs | based file system using LittleFS! Also known

bsg_newlib_dramfs is a C library. bsg_newlib_dramfs has no bugs, it has no vulnerabilities, it has a Strong Copyleft License and it has low support. You can download it from GitHub.

Newlib is a light-weight C standard library implementation for embedded systems. It elegantly separates system specific functionality (system calls) into an easily portable portion called Libgloss. Libgloss contains system call implementations for different architectures/systems in it. Porting Newlib to an architecture/system essentially involves porting these system call implementations in Libgloss. Complete guide for porting Newlib can be found in [5]. Running POSIX programs on bare metal systems require some sort of implementation for file i/o and malloc. Malloc depends on just one system-call called sbrk, which essentially increments or decrements heap pointer as and when requested. Whereas, file i/o requires an actual file system, or an interface that can mimic a file system. This Newlib port, which, we informally refer to as Panic Room, uses an open-source lightweight file-system designed for embedded flash file systems by ARM called LittleFS (LFS). LittleFS also supports a DRAM-based file system, which is the one we use. The idea is to implement file i/o syscalls by simply translating them to LFS function calls, which in turn will operate on memory, rather than trying to use a more complex I/O emulation facility, like proxy kernels, that package up I/O calls and ship them over to a host. This allows for more reproducible I/O emulation, since the host is no longer an asynchronous process. It also eliminates the infrastructure pain caused by mapping these proxy-IO calls to different embodiments of the design -- simulator, VCS, verilator, FPGA emulation, ASIC testboard, and PCI-e hosted chip.