The uClinux distribution is replaced by the Buildroot distribution since the 2012R2 release for Blackfin. Upgrade to the buildroot Linux distribution.
uClinux is an operating system that is derived from the Linux kernel. It is intended for microcontrollers without Memory Management Units (MMU's). It is available on many processor architectures, including the Blackfin processor. The official uClinux site is at http://www.uclinux.org/
The source and documentation found here is specific to the Blackfin processor. The legacy released files can also be found under project buildroot for blackfin. If you have any questions about uClinux for the Blackfin processor please ask them here.