We don't use TBF establishment on CCCH and Immediate Assignment message any more, now we establish Downlink TBF during Uplink TBF and use Packet Downlink Assignment message.
Added function gprs_rlcmac_packet_downlink_assignment() and modified TBF management.
Added functions for writing and sending Immediate Assignment message.
Modified TBF managment for handling Channel Request and Immediate Assignment messages.
1. pcu - main program for GPRS PCU.
2. gprs_rlcmac - RLC/MAC layer implementation for PCU. Added list for TBF, TBF allocation, establishment, release.
3. gprs_bssgp_pcu - BSSGP protocol implementation for PCU.
4. pcu_l1_if - interface for communication PCU application with OpenBTS.