This commit introduces CSFB (circuit switched fall-back) capabilities to
srsLTE. Actually, all the eNB has to do is to send a
RrcConnectionRelease with the RedirectedCarrierInfo IE.
The MME triggers this by the S1AP CS Fallback Indicator IE, which may
be present either in the Initial Context Setup Requst or in the
UE Context Modification Request.
As srsLTE has no support for the UE Context Modification Request at all
yet (!), basic support for this message is introduced in this patch.
Both Mobile Originated and Mobile Terminated CSFB with a coupel of
different UE models have been verified using this patch in a setup
consisting of srsENB attached to an undisclosed EPC connected via SGsAP
to a complete Osmocom 2G network.
Closes: #358Closes: #363
RRC-PHY interface refactor. Moved RRC-MAC interface to rrc_asn1_utils and created RRC-PHY interface also in rrc_asn1_utils. All ASN1 includes should be made from rrc_asn1_utils only keeping ue_interfaces clean of ASN1
Tested with different common and dedicated configurations (64QAM UL, 256QAM, CA, SRS enabled/disabled, etc)
- add interface to RRC to allow NAS to query the DRB for a given
EPS bearer id
- extend interface for NAS to setup GW to also pass LCID of bearer
- in NAS, use this new interface to pass actual LCID of the default
DRB when creating the TUN device
- abstract UE object now consists of a radio, a PHY, and a stack layer
- add new stack abstraction layer that combines MAC, RLC, RRC, PDCP, NAS and GW
- PHY layer now has a single stack interface and does not talk to MAC and RRC seperatly
This entails:
* Adding S1AP paging messaging to the MME.
* Adding the Downlink Data Notification, Donlink Data Notification Acknoledgment, and Downlink Data Notification Failure Messages.
* Adding the logic at the GTP-U to detect that Downlink Data notification needs to be sent.
* Proper handling of the new GTP-C messages at the MME GTPC and SPGW GTPC classes
* Add queuing mechanisms at the GTP-U while waiting for paging response. Queue is flushed when paging fails (timeout or other).
* Make sure eNB's SCTP information is properly stored.
* Make sure UE's GUTI information is properly stored.
* Adding timer creation at NAS using timerfd_create
* Adding the ability to add and remove the timer file descriptor to the MME main select loop
* Adding the ability to the MME for the NAS to check if a timer is running
* Adding the timer expiry handling functionality at the MME
- add a simple and low-overhead has_data() method to check whether
an RLC entity has data to transmit or not
- use this method for all calls that are actually not interested
in the amount of data to send
- use the more expensive get_buffer_state() for all cases where
the actual size of the buffer is of importance
* New parallel Turbodecoder implementation in SSE/AVX 16-bit and 8-bit
* Optimised UL Interleaver
* Include TB CRC calculation in FEC encoder
* New threading priorities
* fixed some issues with the UL scheduling
* Hack to fix UL scheduler
* minor fix
* Cleaned up code and fixed issue with the update_allocation function
* fixed the console printing in the enb
* log/console fix
* fixed the log print
* added a normalization factor
* RLC: entity uses dynamic instances. Simplified stop/reset/reestablish procedure. Added non-blocking interface
* Limit decimals in metrics stdout
* Changed mutexes to rwlock in RLC/RRC/MAC/PDCP to fix race conditions when removing users
* Fix deadlock bug for MIMO
* Remove headers
* Fix missing unlock causing overflows
* Do not decrease CQI when PUCCH (this is a temporal fix, requires to reduce the maximum MCS)
* Fix mutex unlock in worker
* Configurable RLC tx buffer. Default to 512 for enodeb
* Check NULL SDU in write_sdu()
* Protect RLC objects and tx_queue from being destroyed while using it
* Remove superfluous code
* Disable SIB logging
* Fix block_queue for enb
* Consolidated functions in S1AP
* Fixed ASAN in some GCC
* Stop quicker the enb
* Minor typo edit
* Fixed mutexing issues in RRC and possibly RLC/PDCP when adding/removing users
Ismael Gomez
Harald Welte