There's no real use of C++ in that file, and it causes problems when
using llist_head entry macros in future patches adding initial support
for multiple BTS in PCU object, so let's move it to plain C.
Change-Id: Ic771a89fd78b5e66151a5384f0ff6a8895589466
Previous work on BTS class started to get stuff out of the C++ struct
into a C struct (BTS -> struct gprs_glcmac_bts) so that some parts of
it were accessible from C code. Doing so, however, ended up being messy
too, since all code needs to be switching from one object to another,
which actually refer to the same logical component.
Let's instead rejoin the structures and make sure the struct is
accessible and usable from both C and C++ code by rewriting all methods
to be C compatible and converting 3 allocated suboject as pointers.
This way BTS can internally still use those C++ objects while providing
a clean APi to both C and C++ code.
Change-Id: I7d12c896c5ded659ca9d3bff4cf3a3fc857db9dd
We have same kind of object splitted into two layers, in coding_scheme
and gprs_coding_scheme. Let's merge them together and get rid of the
class, which is not really useful because it's only a set of functions
operating on one enum value.
This change also fixes gcc 10.1.0 error about memseting a complex type
in rlc.h init().
Change-Id: Ie9ce2144ba9e8dbba9704d4e0000a2929e3e41df
Newer gcc 10.1.0 is erroring due to memset being applied on a complex
type, so let's start by removing this only function outside of the
struct.
Change-Id: I20426557d9b3049ab275fadb92e10ea8a860a119
As warned by gcc 8.1.0:
osmo-pcu/src/tbf.cpp: In constructor ‘gprs_rlcmac_tbf::gprs_rlcmac_tbf(BTS*, gprs_rlcmac_tbf_direction)’:
osmo-pcu/src/tbf.cpp:222:33: error: ‘void* memset(void*, int, size_t)’ clearing an object of type ‘struct gprs_rlc’ with no trivial copy-assignment; use assignment or value-initialization instead [-Werror=class-memaccess]
memset(&m_rlc, 0, sizeof(m_rlc));
^
In file included from osmo-pcu/src/tbf.h:24,
from osmo-pcu/src/bts.h:37,
from osmo-pcu/src/tbf.cpp:22:
osmo-pcu/src/rlc.h:234:8: note: ‘struct gprs_rlc’ declared here
struct gprs_rlc {
^~~~~~~~
Change-Id: Ifb0529b9ae6cd4300e5cbbd9151054792edbfe06
Reset V_N and V_B in UL/DL window class constructors to make sure we
always start from known initial state.
Related: OS#1759
Change-Id: I8e14ffa913b49c5394229220de9165cdfaabdf19
Fixes: CID70468, CID70469.
* use appropriate types for coding scheme parameters
* add comment regarding possible number of RLCMAC blocks
The code in create_dl_acked_block() has underlying assumption that
rlc.num_data_blocks can never be more than 2, which is true and is
enforced by appropriate asserts but is not obvious when looking at the
function code alone. It's equally hard for Coverity which leads to false
positives in scan.
Lets' make this assumption explicit by putting it into for(;;) condition
alongside with corresponding comment.
Fixes: CID143070
Change-Id: If599a6c8a6ef56d847604fcf41bb71decccd8a78
This test case is for testing generation of
EGPRS PUAN. Corresponding log files .ok and .err
are modified.
Change-Id: I18e6d4a9e90fd6453fe14187beab27dfeae8dbe9
This adds compression of bitmap in PUAN. The compressed bitmap
is used only if the number of bits in the bitmap does not fit in
the message and there is a gain after compression.
The algorithm is part of libosmocore and so there is dependency
on the libosmocore for compilation.
The algorithm is tested on integration setup by forcing compression.
Change-Id: Id2eec4b5eb6da0ebd24054b541b09b700b9b40ba
Modify the EGPRS DL TBF flow to support Split block during
Retx. This patch will also Upgrade the test suite with test cases
to validate the EGPRS Downlink SPB for Retransmission
Scenarios like MCS6->MCS3, MCS4->MCS1, MCS5->MCS2, MCS9->MCS3
MCS7->MCS2, MCS8->MCS3 have been simulated and Integration tested
in NuRAN 1.0 hardware thoroughly.
Change-Id: I242afdd8ae7622dec8593b26382ad66bad5b9516
Modify the header files with necessary data structure to handle
Split block for EGPRS DL TBF.
The EGPRS resegmentation feature allows PCU to retransmit
RLC blocks of HeaderType1, HeaderType2 by segmenting
them to 2 HeaderType3 blocks(Example MCS5 will be
retransmitted as 2 MCS2 blocks). Table 10.4.8b.2 of 44.060
explains the possible values of SPB in HeadrType3 for DL
direction. The PCU decides to retransmit the
blocks by resegmenting it based on Table 8.1.1.1 of 44.060.
The retransmission MCS is calculated based on current MCS of
the Block and demanded MCS by PCU. Section 10.3a.3.3 of 44.060
shows the HeadrType3 with SPB field present in it
Change-Id: I57673e53a9da2affa7e8aaa6551ac4b271c3d525
Modify header files with data structures required
to support split blocks for EGPRS UL TBF
This feature provides provision for MS to retransmit
RLC blocks of HeaderType1, HeaderType2 by segmenting
them to 2 HeaderType3 blocks(Example MCS5 will be
retransmitted as 2 MCS2 blocks). Table 10.4.8b.1 of 44.060
explains the possible values of SPB in HeadrType3 for UL
direction. When the MCS is changed at the PCU, PCU directs the
changed MCS to MS by PUAN or UPLINK ASSIGNMENT message along
with RESEGMENT flag, Then MS may decide to retransmit the
blocks by resegmenting it based on Table 8.1.1.1 of 44.060.
The retransmission MCS is calculated based on current MCS of
the Block and demanded MCS by PCU. Section 10.3a.4.3 of 44.060
shows the HeadrType3 with SPB field present in it.
Change-Id: I83ccd136bb361adcfd511c57c5a9d95ed72c36c2
EGPRS Type 1, 2, and 3 headers are used by OsmoPCU and OsmoBTS.
Move the header definitions to libosmocore to be shared by both
packages.
Modify the struct variable naming to use *_hi/*_lo instead of
*_a/*_b in order to be consistent with existing naming used in
libosmocore.
Change-Id: I98687ad981d27502aec42729611937ba1caf207c
Modify the existing data structure to support ARQ-II for Retx in EGPRS DL.
This will also hadle compilation issue related to renaming the variable.
Change-Id: I734b1024bb32f2daa43af4adf59f4a17f2294afe
It's the block data, not the history.
Also add including LI headers.
Change-Id: Id4d99d1d21c7fa372771fd569d87bbcf2c6b6d22
Reviewed-on: https://gerrit.osmocom.org/144
Reviewed-by: Harald Welte <laforge@gnumonks.org>
Tested-by: Jenkins Builder
The second #define RLC_EGPRS_SNS is 3 lines below of the first one.
Change-Id: Ibb718ba9be21831c56c5949e730fab5acd691d7c
Reviewed-on: https://gerrit.osmocom.org/107
Tested-by: Jenkins Builder
Reviewed-by: Holger Freyther <holger@freyther.de>
Adds support to find the puncturing scheme for retransmission
with MCS change, retransmission with no MCS change, transmission
case. Puncturing scheme selection for retransmission case with
MCS change is aligned with TS 44.060 9.3.2.1. Puncturing scheme
selection for retransmission without MCS change, fresh transmission
is aligned with TS 44.060 10.4.8a.3.1, 10.4.8a.2.1, 10.4.8a.1.1
Define new data structure with respect to TS 44.060
10.4.8a.3.1, 10.4.8a.2.1, 10.4.8a.1.1 for puncturing scheme values
and initialize the variable introduced
Currently only one BSN block is encoded in each RLC data message,
even if MSC7-9 are used, which transport two independant (except for a
max BSN delta of 512) BSN blocks. In that case, the same block is
just put twice into the same message.
The current create_dl_acked_block(fn, ts) method handles
block selection (resend, new BSN, dummy block, ...) and restart
handling in one method and is too complex to extend it accordingly.
Therefore this commit move the block selection/creation handling into
a new method (take_next_bsn) which delivers the next BSN along with a
hint, whether it may be combined with another block. In that case,
the function can be called a second time (this time with a valid
previous BSN, that's the one returned by the first call) to get the
second BSN. The real block generation method
create_dl_acked_block(fn, ts, index, index2) is then called with both
BSNs as indices (the second must be -1, if there is only one BSN).
Note that every BSN returned by take_next_bsn should be passed to
create_dl_acked_block to avoid state inconsistencies.
Sponsored-by: On-Waves ehf
To access EGPRS data blocks, the optional padding must be taken into
account. Whether padding has been used must be dervied from the CPS
field in the header of the RLC EGPRS data message.
Add this function to decode the CPS value and extract that
information.
Sponsored-by: On-Waves ehf
The offsets of the data areas change when padding is used (see TS
44.060, 9.3.2.1 and Annex J for details).
Extend the parameter lists to pass the with_padding flag and use
that information to compute the correct offsets.
Sponsored-by: On-Waves ehf
Currently only header type 3 (MCS-1 to MCS-4) is supported.
Add header structs to rlc.h and extend
Encoding::rlc_write_dl_data_header accordingly.
Sponsored-by: On-Waves ehf
Currently gprs_rlc_ul_window and gprs_rlc_dl_window are completely
separate classes, containing several identical members and methods.
This commit add a shared parent class containing WS and SNS handling.
Sponsored-by: On-Waves ehf
The current methods are based on the GRPS specific RBB and SSN values
and formats which are not compatible with EGPRS.
Add a second set of similar methods with the same semantics but
which are based on a bitvec and the first BSN instead.
The following methods are affected:
- gprs_rlc_dl_window::update
- gprs_rlcmac_dl_tbf::rcvd_dl_ack
- gprs_rlcmac_dl_tbf::update_window
Sponsored-by: On-Waves ehf
The MS' RLC receiver needs a valid CPS field to decode the block.
Add the function gprs_rlc_mcs_cps to generate the CPS value based on
coding scheme, puncturing, and padding.
Sponsored-by: On-Waves ehf
Currently the (GPRS) RLC block encoding is done by setting the
header fields directly in gprs_rlcmac_dl_tbf::create_new_bsn.
This is much more complex with EGPRS, since the data fields are
not byte aligned, the header formats depend on the header type,
and the mapping of bits to bytes is LSB first.
This commit adds Encoding::rlc_write_dl_data_header which writes
the header according to the given gprs_rlc_data_header structure.
Encoding::rlc_copy_from_aligned_buffer is also added to copy
byte sequences into the message.
Note that the actual encoding of data units is not yet present.
Sponsored-by: On-Waves ehf
Add the functions gprs_rlc_data_info_init_dl/ul which initialise a
gprs_rlc_data_info structure depending on the coding scheme. The
fields num_data_blocks, data_offs_bits, cs, and the data_blocks are
valid after this call. The other fields are set to 0.
The data blocks are initialised to the correct data_len, e == 1
(no extension header field), cv == 15 (not a final block). The other
data block fields are set to 0.
The gprs_rlc_data_block_info can also be initialised separately
by using the gprs_rlc_data_block_info_init function.
Sponsored-by: On-Waves ehf
These struct names are more specific than necessary. They are used
for GPRS (uplink) already. In downlink direction, only a few fields
will be added to the header struct. Add addition,
gprs_rlc_ul_header_egprs does not map directly to an encoded
header, like many other 'header' structs do.
Change the names to fit both modes and both directions:
gprs_rlc_ul_header_egprs -> gprs_rlc_data_info
gprs_rlc_ul_data_block_info -> gprs_rlc_data_block_info
Sponsored-by: On-Waves ehf
LListHead does basically the same like llist_pods, but more C++ish
and with type safety.
This commit turns the former list field of gprs_rlcmac_tbf into a
private field, provides accessors, moves the related code from
pcu_vty.c to pcu_vty_functions.cpp, and removes the llist_pods
type and related code.
Sponsored-by: On-Waves ehf
Currently the values for WS and SNS are fixed to 64 (WS) and 128
(SNS) which are the only values that can be used with GPRS. On the
other hand, EGPRS requires an SNS of 2014 and a WS in the range of
64 to 1024.
This commit adds member variables and setters to both window
classes. By default, the GPRS values are being used.
Sponsored-by: On-Waves ehf
Currently the gprs_rlc_dl_window and gprs_rlc_ul_window do not have
constructors, but need to get initialized explicitly.
This commit adds constructors to both classes and removes explicit
external initialization code.
Sponsored-by: On-Waves ehf
Currently in some places uint8_t is being used to encode BSNs and
SSNs. This is inconsistent and (even worse) not enough for EPGRS
which uses an SNS of 2014.
This commit changes these to uint16_t.
Sponsored-by: On-Waves ehf
Currently there is only a mod_sns() method which is being used in
expression like bsn_expr & win.mod_sns(). This only works, because
it is known that mod_sns() is (sns() - 1) where sns() in turn is
always 2^n. This is error prone, hard to read, and relies on window
specifics that should be kept inside the respective module.
This commit adds a mod_sns(uint bsn) method to gprs_rlc_ul_window and
gprs_rlc_dl_window, that encapsulates and hides this optimized
computation.
Sponsored-by: On-Waves ehf
The current rcv_data_block_acknowledged_gprs method is tightly
coupled to GPRS.
This commit adds variants of the involved methods that support
EGPRS and GPRS RLC encodings likewise.
Sponsored-by: On-Waves ehf
Currently the coding scene is stored as number N, where there scheme
is CS-N.
This commit replaces this by a GprsCodingScheme type cs value. The
gprs_rlcmac_cs table is no longer needed and thus removed.
Sponsored-by: On-Waves ehf
These methods will be needed for EGPRS decoding.
The is_received method returns true iff a block with the given BSN
has already been received in the current window. A call to
invalidate_bsn marks the block as not received.
Sponsored-by: On-Waves ehf
Currently gprs_rlc_ul_window::receive_bsn calls raise_v_q and returns
the number of RLC data blocks that can be taken from the queue. This
does not fit the EGPRS feature to put 2 independant data blocks in a
single RLC block.
This commit removes raise_v_q from receive_bsn, hence it must be
called explicitely to get the number of processable data blocks.
Sponsored-by: On-Waves ehf
This commit adds new RLC block decoder functions that support both
GPRS and EGPRS. The code path is selected based on the value of the
GprsCodingScheme cs object.
- rlc_parse_ul_data_header
parses the header of an RLC data block including the E and FBI/TI
flags (currently supported CS-1 - CS-4, MCS-1 - MCS-4).
- rlc_copy_to_aligned_buffer
copies an RLC data unit to a byte aligned buffer and returns
the unit's length.
- rlc_get_data_aligned
is a convenience wrapper around rlc_copy_to_aligned_buffer
that avoids copying if the data unit is already byte aligned.
Sponsored-by: On-Waves ehf
Currently the declarations of rlc_ul_header, rlc_dl_header, and
rlc_li_field silently assume that a gcc for a little endian platform
is being used.
This commit adds '#if OSMO_IS_LITTLE_ENDIAN' the ensure the correct
byte ordering.
Sponsored-by: On-Waves ehf
To cope with transmission failures due to bad radio conditions, a
different coding scheme with more redundance can be used.
This commit adds an implemenation that is based on the Ack/Nack
ratio per PACKET DOWNLINK ACK/NACK message received from the MS.
Basically the CS level is decreased, if the block error rate goes
above cs_adj_upper_limit (default 33%), and it is increased, if the
rate drops below cs_adj_lower_limit (default 10%). Only blocks that
have been encoded with the current CS are taken into account.
Note that this approach doesn't measure the MS->BTS conditions and
that the measurement values reported by the MS are not taken into
account.
Ticket: #1739
Sponsored-by: On-Waves ehf
Pau Espin
Pau Espin Pedrol