[U-Boot-Users] Tree folders

Hey ubooters,

First at all I'm new to u-boot, so maybe the answer is obvious. I was taking a look at the tree layout in u-boot-v2 and I've noticed that in drivers folder the cfi_xxx files are not inside any folder.

../drivers/cfi_flash.c /cfi_flash_amd.c /cfi_flash_intel.c /cfi_flash_new.c

If I'm not wrong cfi is used for NOR memories. Why they are not inside for example a "nor" folder?