HelenOS sources

RCTL_UPE          737 uspace/drv/nic/e1k/e1k.c 	rctl = rctl & ~RCTL_UPE;
RCTL_UPE          749 uspace/drv/nic/e1k/e1k.c 	rctl = rctl | RCTL_UPE;
HelenOS homepage, sources at GitHub