devmem2
devmem2 was originally developed by Jan-Derk Bakker in 2000 and released under GPLv2. After a while, the original download location was no longer available, but nice folks from Bootlin preserved it on their mirror.
Over the years, the number of patches grew and managing the source code in the form of patches, applied on top of the original, became problematic and hence, this repo was created.
Brief history of corresponding recipe in OpenEmbedded showing code changes and its evolution through the years: