Commit Graph

212 Commits

Author SHA1 Message Date
Jacob Erlbeck 1e17fffa05 tbf/tests: Add tests for EGPRS TBF establishment
Add a test for EGPRS two phase access based on RA caps.

Add a test for DL TBFs where data block are encoded with each MCS.

Sponsored-by: On-Waves ehf
2016-02-04 11:09:19 +01:00
Jacob Erlbeck fc6d572c07 rlc: Add with_padding argument to gprs_rlc_data_info_init_dl/ul
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
2016-02-03 19:23:49 +01:00
Jacob Erlbeck 6c273dc8e7 cs: Add GprsCodingScheme::optionalPaddingBits
Return the amount of optional padding bits, which is 6*8 for
MCS-3 and MCS-6 and 0 for all other coding schemes. The padding
is needed the encode 68 byte data blocks (MCS-8) with these schemes.
See TS 44.060, 9.3.2.1 and Annex J for details.

Sponsored-by: On-Waves ehf
2016-02-03 19:23:49 +01:00
Jacob Erlbeck fba39469aa cs: Add family related methods
Add family handling and the related methods family,
isFamilyCompatible, isCombinable, decToSingleBlock to
GprsCodingScheme.

Sponsored-by: On-Waves ehf
2016-02-03 16:59:38 +01:00
Jacob Erlbeck a697c18053 WIP: Add decoding test based on real RLC messages (TODO) 2016-02-02 17:06:40 +01:00
Jacob Erlbeck 205a943205 WIP: Add state ASSIGNING (TODO)
entered when the assigment is really sent

Ticket: OW#????
Sponsored-by: On-Waves ehf
2016-02-02 17:06:39 +01:00
Jacob Erlbeck b7232c9bf0 tbf: Use TLLI as ID if TFI not yet assigned
Currently the old TFI is always used as ID when a
PACKET DOWNLINK ASSIGNMENT is generated. This fails
if the old TBF has not been fully assigned yet. The
MS will then ignore the PDA.

This commit changes write_packet_downlink_assignment to accept
an additional parameter old_tfi_is_valid and uses the new TBF's
TLLI instead of the olf TFI if that parameter is set to false.

Sponsored-by: On-Waves ehf
2016-02-02 17:06:38 +01:00
Jacob Erlbeck 7bd5e6522f tbf: Add check_polling/set_polling (TODO)
Ticket: OW#????
Sponsored-by: On-Waves ehf
2016-02-02 17:06:38 +01:00
Jacob Erlbeck f2594e07eb tbf: Add and use tbf->poll_ts
Currently tbf->control_ts is used to look up an incoming poll
response. Since that may eventually change, poll timeouts could
theoretically happen in that case.

Store the real poll TS in tbf->poll_ts at all places where
tbf->poll_fn is set. Do not use tbf->control_ts to look up
outstanding polls.

Sponsored-by: On-Waves ehf
2016-02-02 17:06:38 +01:00
Jacob Erlbeck 4750aeed98 FIXUP Do not reuse old TBF after RACH requests (TODO)
Check:
 Send dowlink assignment on PACCH, because TBF(TFI=0 TLLI=0xf1223344
 DIR=UL STAT
 E=FLOW) exists
 -TBF(TFI=1 TLLI=0xf1223344 DIR=DL STATE=NULL) changes state from
 NULL to ASSIGN
 -TBF(TFI=1 TLLI=0xf1223344 DIR=DL STATE=ASSIGN) starting timer 0.
 +TBF(TFI=0 TLLI=0xf1223344 DIR=DL STATE=NULL) changes state from
 NULL to ASSIGN
 +TBF(TFI=0 TLLI=0xf1223344 DIR=DL STATE=ASSIGN) starting timer 0.

Ticket: OW#????
Sponsored-by: On-Waves ehf
2016-02-02 17:06:37 +01:00
Jacob Erlbeck 575ede1781 tbf: Add abort method for downlink TBF
Currently the is a release() function which takes care of
statistics and shutdown of properly finished TBFs, but which
cannot be used for aborted TBFs.

This commit add an abort() method which handles unacked RLC blocks
as lost and doesn't start a release timer. This method will be
invoked by tbf_free() for downlink TBF.

Sponsored-by: On-Waves ehf
2016-02-02 17:06:37 +01:00
Jacob Erlbeck 87bada76e2 tbf: Refactor calls to write_immediate_assignment
Make use of variables, log them to LOGL_DEBUG, and reduce code
duplication.

This should help to narrow down the cause why snd_dl_ass are not
answered by the MS sometimes.

Sponsored-by: On-Waves ehf
2016-02-02 17:06:36 +01:00
Jacob Erlbeck f185480687 tbf: Low prio for BSSPG values for GPRS/EGPRS MS class
Currently the values in the BSSGP RA Cap IE are eventually use
overwrite the 'good' values obtained from the MS earlier.

Use the 'good' values when the are present, which is assumed if
at least one of ms->ms_class() or ms->egprs_ms_class() is set.

Sponsored-by: On-Waves ehf
2016-02-02 17:06:36 +01:00
Jacob Erlbeck 5f8716a663 edge: Make window size configurable
Currently the window size is fixed to 64 even for EGPRS.

Support dynamic window sizes depending on the number of PDCH. The
WS can be set to b + f * N_PDCH. If the result is not valid according
to TS 44.060, Table 9.1.9.2.1, the value will be corrected to use the
next lower valid value (or 64).

The following VTY commands are added (config-pcu node):

  window-size <0-1024>          set base (b) value and leave f unchanged
  window-size <0-1024> <0-256>  set base (b) and factor (f)

Sponsored-by: On-Waves ehf
2016-02-02 17:06:36 +01:00
Jacob Erlbeck fec13ebcef edge: Disable GPRS/EGPRS mixed mode
Currently the plain 'egprs' command enables EGPRS but doesn't prevent
phones from being served in GPRS mode if they do not support EGPRS.
This involves complex frame allocation implementations in dynamic
mode, especially if 8PSK is being used. This is due to the inability
of non-EGPRS phone to decode 8PSK USF and ES/P altogether. Since
polling has a higher priority than USF, collisions will have to be
prevented by the PCU by never using an GPRS USF if it refers to a FN
that is already being used for polling.

This commit just disables mixed usage by ignoring GPRS-only request
if EGPRS is enabled.

The following VTY command (config-pcu node) is changed:

  egprs     ->   egprs only

Sponsored-by: On-Waves ehf
2016-02-02 17:06:35 +01:00
Jacob Erlbeck bcb18d8c03 FIXUP "fix analyse_error to handle num_blocks"
Ticket: OW#????
Sponsored-by: On-Waves ehf
2016-02-02 17:06:35 +01:00
Jacob Erlbeck c035235576 edge: Fix handling of FINAL_ACK_INDICATION
The bitmap related fields are undefined when FINAL_ACK_INDICATION
is set.

Derive the bitmap from the current V(B). By doing this, a valid
bitmap is always generated. Thus the ack/nack handling can always
be done the same way, while only the TBF state related changes still
depend on that flag.

Sponsored-by: On-Waves ehf
2016-02-02 17:06:34 +01:00
Jacob Erlbeck 695c51e6c9 FIXUP cleanup DEBUG
Ticket: OW#????
Sponsored-by: On-Waves ehf
2016-02-02 17:06:34 +01:00
Jacob Erlbeck 0429c41779 edge: Fix rlc_data_to_dl_append_egprs
Ticket: OW#????
Sponsored-by: On-Waves ehf
2016-02-02 17:06:34 +01:00
Jacob Erlbeck 85d07dd568 WIP: fix Decoding::decode_gprs_acknack_bits
Only return bits starting with V(A).

Ticket: OW#????
Sponsored-by: On-Waves ehf
2016-02-02 17:06:33 +01:00
Jacob Erlbeck 4210e9c53c DEBUG: Show received bitmap directly
Ticket: OW#????
Sponsored-by: On-Waves ehf
2016-02-02 17:06:33 +01:00
Jacob Erlbeck fffd366c6c WIP: Provide and use CS -> CPS conversion
Ticket: OW#????
Sponsored-by: On-Waves ehf
2016-02-02 17:06:32 +01:00
Jacob Erlbeck 9de475d8f3 edge: Support MCS data block encoding
Currently only GPRS data block encoding is supported.

This commit adds rlc_data_to_dl_append_egprs which does the EGPRS
specific extension and chunk handling. It extends
Encoding::rlc_data_to_dl_append to use that function for MCS coding
schemes.

Sponsored-by: On-Waves ehf
2016-02-02 17:06:32 +01:00
Jacob Erlbeck 6f880fc146 edge: Select implementation by mode in rlc_data_to_dl_append
Currently the GPRS data block encoding is applied to every
coding scheme, even if an MCS is selected.

This commit renames the actual encoding function to
rlc_data_to_dl_append_gprs (not exported) and puts
selection code into Encoding::rlc_data_to_dl_append. This
requires an additional cs argument.

Sponsored-by: On-Waves ehf
2016-02-02 17:06:32 +01:00
Jacob Erlbeck 86d410b284 edge: Use rlc_data_to_dl_append in create_new_bsn (TODO)
Currently TBF related tasks (status changes, counter updates,
LLC dummy command insertion) as well as
RLC data block generation are done within create_new_bsn.
The data block creation part has already been copied to
the stateless Encoding::rlc_data_to_dl_append function.

This commit changes create_new_bsn to use the encoder function and
just care about the TBF related stuff.

Since the rlc_data_to_dl_append function has been validated against
the test cases being described in annex B of TS 44.060, this
commit fixes an encoder bug which leads to broken LLC frames in
a special case (see example B.2, the main header's E bit was
erroneously set to 1 in that case). When this happens, the LLC frame
will get discarded after reassembly, so that TCP will have to
retransmit the lost packet.

Sponsored-by: On-Waves ehf
2016-02-02 17:06:32 +01:00
Jacob Erlbeck 7b38e07595 edge: Add Encoding::rlc_data_to_dl_append
This function appends a single chunk to an RLC downlink data block.
The implementation is basically taken from the
gprs_rlcmac_dl_tbf::create_new_bsn method without the TBF related
functionality and any side effects.

Note that it still only supports GRPS.

Sponsored-by: On-Waves ehf
2016-02-02 17:06:32 +01:00
Jacob Erlbeck 269955ffcf edge: Use RLC data block encoding functions
This commit removes the use of struct rlc_dl_header from
gprs_rlcmac_dl_tbf::create_dl_acked_block and
gprs_rlcmac_dl_tbf::create_new_bsn. Instead of patching the
data area directly, the RLC block encoding functions are used.

Note that the data unit encoding is still hard-coded to GPRS in
create_new_bsn, so using MCS 1-4 (albeit being supported by the
encoder) will not work yet.

Sponsored-by: On-Waves ehf
2016-02-02 17:06:32 +01:00
Jacob Erlbeck 251d609eb2 test: Add function name printfs (TODO)
Some of these are missing and added by this commit.

TODO:
 - Add all of them
 - Fix ok file(s)

Sponsored-by: On-Waves ehf
2016-02-02 17:06:31 +01:00
Jacob Erlbeck 94d00ea72f edge: Add encoder for downlink RLC data blocks
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
2016-02-02 17:06:31 +01:00
Jacob Erlbeck 64a16384c9 edge: Add init functions for gprs_rlc_data_info
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
2016-02-02 17:06:31 +01:00
Jacob Erlbeck 9c165a1baf edge: Fix RLC message size
Currently the RLC message length that is obtained from the DSP is
reduced by 1 if the last byte of the buffer includes spare bits.
While this worked well with GPRS, these bits are being used to
encode RLC blocks in EGPRS mode. Thus this last byte must not be
chopped off. The functionality of the code is not affected by this,
since the modified length value is not used.

This commit adds GprsCodingScheme::usedSizeDL/UL to return
the number of bytes needed to encode the message block. If there are
single bits at the end that are to be used (EGPRS), the functions
return the number of full bytes plus 1 (which is the buffer size
reported by the DSP and returned by sizeUL/sizeDL). The commit also
removes the len parameter from rcv_data_block_acknowledged.

Sponsored-by: On-Waves ehf
2016-02-01 13:58:15 +01:00
Jacob Erlbeck 259dd69151 edge: Rename gprs_rlc_ul_header_egprs and gprs_rlc_ul_data_block_info
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
2016-02-01 13:58:15 +01:00
Jacob Erlbeck 4231126165 edge: Enable EGPRS in downlink TBFs (TODO)
TODO:
 - cm

Sponsored-by: On-Waves ehf
2016-02-01 13:58:14 +01:00
Jacob Erlbeck cb7289094a edge: Replace integer cs by GprsCodingScheme
Currently the TBF and MS object use a plain integer value
(current_cs) to manage the coding scheme. This makes it difficult to
support the MCS schemes. GprsCodingScheme supports a partial ordering
of these values (CS and MCS) and provides safe increment and
decrement methods.

Use the GprsCodingScheme type instead of integer for cs fields and
variables. Add a 'mode' to GprsMs which can be set to either GPRS,
EGPRS, or EGPRS_GMSK which also set the initial values of
current_cs_ul/dl. Select the mode based on max_mcs_ul and max_mcs_dl.

Sponsored-by: On-Waves ehf
2016-02-01 13:58:14 +01:00
Jacob Erlbeck 4c9e549aa3 edge: Add methods and operators to GprsCodingScheme
Add a few new operators and methods to support the use of
GprsCodingScheme instead of the plain integer currently used.

Sponsored-by: On-Waves ehf
2016-02-01 13:58:14 +01:00
Jacob Erlbeck ed2dbf6954 tbf: Use LListHead instead of llist_pods
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
2016-02-01 13:58:13 +01:00
Jacob Erlbeck 38f18698b3 edge/test: Rename test_rlc_decoder to test_rlc_unit_decoder
This test only covers RLC data units and not whole RLC messages.

Sponsored-by: On-Waves ehf
2016-02-01 13:58:13 +01:00
Jacob Erlbeck a3a567e765 rlc: Add constructor to window classes
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
2016-02-01 13:58:12 +01:00
Jacob Erlbeck d88bb2e825 rlc: Dump RLC data for debugging
Log incoming RLC data messages and RLC data units to LOGL_DEBUG.

Sponsored-by: On-Waves ehf
2016-02-01 13:58:12 +01:00
Jacob Erlbeck 554a835e90 edge: Use a single PDCH rcv_data_block method for GPRS and EGPRS
Currently GPRS is handled by the old code path while EGPRS already
uses the unified functions. The rcv_block_egprs is basically not
specific to EGPRS and just needs minor modifications to handle GPRS.

This commit turns gprs_rlcmac_pdch::rcv_block_egprs into a unified
rcv_data_block method and uses it for GPRS, too.

Note that the logging messages of the new parser are different.

Sponsored-by: On-Waves ehf
2015-12-16 19:57:09 +01:00
Jacob Erlbeck e8f5fe5255 tbf: Refactor parts of extract_tlli into set_tlli_from_ul
Currently gprs_rlcmac_tbf::extract_tlli takes care of decoding and
the TBF update. These are really different things and doing the
decoding in extract_tlli makes EGPRS support more complex.

This commit moves the TBF state related part into a new method
gprs_rlcmac_tbf::set_tlli_from_ul.

Sponsored-by: On-Waves ehf
2015-12-16 19:37:49 +01:00
Jacob Erlbeck d87e1d6ab7 rlc: Do not raise_v_q in receive_bsn
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
2015-12-16 19:37:08 +01:00
Jacob Erlbeck 6167925147 edge: Add test cases for rlc_data_from_ul_data
This checks the example test cases given in appendix B of
TS 44.060.

Sponsored-by: On-Waves ehf
2015-12-16 19:36:10 +01:00
Jacob Erlbeck 392a545336 edge: Add information about data blocks to GprsCodingScheme
This commit adds the methods maxDataBlockBytes and numDataBlocks
which provide information about the data areas within RLC messages.
In these areas, the extension bytes, TLLI, and the LLC data are
stored.

Sponsored-by: On-Waves ehf
2015-12-15 15:19:43 +01:00
Jacob Erlbeck 6c3dc61db5 edge: Add header type property to GprsCodingScheme
The header type depends on the coding scheme, for GPRS there is a
single data header type per direction, for EGPRS there are 3 per
direction. In addition, control block header types are used with CS-1
only, so there is one of the per direction altogether for GRPS and
EGPRS.

This commit adds the header type enum and two methods headerTypeData
and headerTypeControl.

Sponsored-by: On-Waves ehf
2015-12-15 15:19:43 +01:00
Jacob Erlbeck 9e862e1e7f edge: Use GprsCodingScheme to adjust the UL RLC block size
Currently the block size is mapped by a switch statement to strip
extra bits that are not used for RLC blocks. That information is
already available via the GprsCodingScheme class.

This commit moves the CS/MCS detection to the rcv_block message and
passes the cs object via rcv_block_gprs, where the length gets
adjusted, to gprs_rlcmac_pdch::rcv_data_block_acknowledged. There the
switch statement is removed.

Note that the TbfTest.err changes due to an additional log message.

Sponsored-by: On-Waves ehf
2015-12-15 15:19:42 +01:00
Jacob Erlbeck d0222cfe2d edge: Add test for GprsCodingScheme
This test checks constructors, predicates, and operators of the
GprsCodingScheme class.

Sponsored-by: On-Waves ehf
2015-12-15 15:19:42 +01:00
Jacob Erlbeck 14e00f8f66 edge: Extend gprs_rlcmac_dl_tbf::handle by egprs_ms_class
The multislot (MS) class and the EGPRS MS class can also be passed
via BSSGP in an MS Radio Access Capability element which can
optionally be contained in a DL-UNITDATA PDU. While this case is fully
supported for GPRS, the EGPRS MS class in BSSGP messages is ignored.

This commit extends gprs_rlcmac_dl_tbf::handle to pass the EGPRS MS
class, too.

Note, that the EGPRS class is not yet taken from the CSN.1 RA
capability and is always set to 0. Note also, that append_data
still uses ms_class only.

Sponsored-by: On-Waves ehf
2015-12-15 15:19:42 +01:00
Jacob Erlbeck 86b6f05d19 edge: Support EGPRS multislot class handling in tbf_alloc
Add an egprs_ms_class argument to the allocation functions and
set/pass it where necessary.

Sponsored-by: On-Waves ehf
2015-12-15 15:17:51 +01:00
Jacob Erlbeck 2db0f08e08 bssgp: Use measured leak rate for flow control
The leak rate sent to the SGSN does not reflect the current CS level,
lost frames, and control message overhead. So the SGSN cannot do
proper queue control under non-optimal conditions.

This commit computes the leak rate for the last flow control interval
by computing the maximum theoretical leak rate and basically
substracting control blocks, nacked blocks, and reduced block sizes
due to CS downgrade. By using this approach, the value will by more
stable on low load, where the value will tend to be near the value
derived from the configuration. On full load the transmitted value is
completely derived from the measurements.

Note that the MS default values are no adapted to the adapted BVC
leak rate, since a single MS which has a lower link quality would
otherwise be reducing the rate of another MS with good radio
conditions, which would not make much sense if they did not share any
PDCH.

Sponsored-by: On-Waves ehf
2015-09-11 11:52:02 +02:00