There is a recent report of working SGX drivers for the 3.8.13 kernel on
the TI forums:
I won't have time to test this for several days, but if anyone here
wants to try building a 3.8.13 BeagleBone kernel with GPU drivers,
please give it a shot!
I'm not sure if the reported success was for a BeagleBone kernel or just
a generic 3.8.13 AM335x kernel. If you do try to build a kernel, please
let us all know the results! IIRC, the last time I tried this, I got
stuck on some issues with the patched-up HDMI support added for the
BeagleBone that kept the kernel from building properly.