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Author SHA1 Message Date
Vadim Yanitskiy 1bffe899d9 trxcon/scheduler: introduce TCH/H TDMA frame mapping helpres
Unlike xCCH, TCH/H channels are using block diagonal interleaving,
so every single burst carries 57 bits of one traffic frame, and 57
bits of another one. Moreover, unlike TCH/F where both traffic
and FACCH/F frames are interleaved over 8 bursts, a FACCH/H is
interleaved over 6 bursts, while a traffic frame is interleaved
over 4 bursts.

This is why a TCH/H burst transmission can't be initiated on
an arbitrary TDMA frame number. It shall be aligned as of
stated in GSM 05.02, clause 7, table 1.

This change introduces two basic functions:

  - sched_tchh_block_map_fn - checks if a TCH/H block transmission
    can be initiated / finished on a given frame number
    and a given channel type;

  - sched_tchh_block_dl_first_fn - calculates TDMA frame number of
    the first burst using given frame number of the last burst;

and some auxiliary wrappers to simplify the usage of
sched_tchh_block_map_fn().

Change-Id: Iaf4cb33f1b79df23f8a90c8b14ebe0cd9907fbb9
2018-09-16 02:12:09 +07:00