diff options
author | Vadim Yanitskiy <vyanitskiy@sysmocom.de> | 2020-06-28 10:48:50 +0700 |
---|---|---|
committer | laforge <laforge@osmocom.org> | 2020-08-04 10:16:36 +0000 |
commit | 10e64630ce24b6ab9b7546374a2a149fd2235ccc (patch) | |
tree | ac3cc21c1ea34efc5bca6197bd2aae435397d73a /src | |
parent | 9d5e955ea1b164217b9734a7806b412495899750 (diff) |
osmo-bts-trx/scheduler: refactor dummy burst scheduling
This change facilitates the upcoming freq. hopping implementation,
in particular scheduling of dummy bursts on C0 with hopping time-
slots. One problem is that we cannot know in advance, whether to
send a dummy burst on a given timeslot unless all transceivers are
processed. For example, trx#3 may want to send a normal burst on
ARFCN of trx#0 (C0), while we have already sent a dummy burst...
Another important aspect is that we shall not be sending dummy
bursts on transceivers other than C0. Scheduling dummy bursts
from _sched_dl_burst() in the context of a single hopping timeslot
of a single transceiver leaves trx_sched_fn() no way to know
whether it's a dummy burst or something else.
Let's solve both problems by moving dummy burst scheduling logic
from _sched_dl_burst() to trx_sched_fn(). Maintain C0 slot-mask
in the inner (per-trx) loop, so that we can fill missing bursts
with dummy bursts afterwards.
Change-Id: I8c3651c27d2991079e83b8abdb7e2c3f95b97a43
Related: SYS#4868, OS#4546
Diffstat (limited to 'src')
-rw-r--r-- | src/common/scheduler.c | 22 | ||||
-rw-r--r-- | src/osmo-bts-trx/scheduler_trx.c | 23 |
2 files changed, 28 insertions, 17 deletions
diff --git a/src/common/scheduler.c b/src/common/scheduler.c index 7375a1ae..c5b38307 100644 --- a/src/common/scheduler.c +++ b/src/common/scheduler.c @@ -52,8 +52,9 @@ static int rts_tchf_fn(struct l1sched_trx *l1t, uint8_t tn, uint32_t fn, enum trx_chan_type chan); static int rts_tchh_fn(struct l1sched_trx *l1t, uint8_t tn, uint32_t fn, enum trx_chan_type chan); + /*! \brief Dummy Burst (TS 05.02 Chapter 5.2.6) */ -static const ubit_t dummy_burst[GSM_BURST_LEN] = { +const ubit_t _sched_dummy_burst[GSM_BURST_LEN] = { 0,0,0, 1,1,1,1,1,0,1,1,0,1,1,1,0,1,1,0,0,0,0,0,1,0,1,0,0,1,0,0,1,1,1,0, 0,0,0,0,1,0,0,1,0,0,0,1,0,0,0,0,0,0,0,1,1,1,1,1,0,0,0,1,1,1,0,0, @@ -1189,7 +1190,7 @@ void _sched_dl_burst(struct l1sched_trx *l1t, struct trx_dl_burst_req *br) enum trx_chan_type chan; if (!l1ts->mf_index) - goto no_data; + return; /* get frame from multiframe */ period = l1ts->mf_period; @@ -1204,11 +1205,11 @@ void _sched_dl_burst(struct l1sched_trx *l1t, struct trx_dl_burst_req *br) /* check if channel is active */ if (!TRX_CHAN_IS_ACTIVE(l1cs, chan)) - goto no_data; + return; /* get burst from function */ if (func(l1t, chan, bid, br) != 0) - goto no_data; + return; /* BS Power reduction (in dB) per logical channel */ if (l1cs->lchan != NULL) @@ -1225,19 +1226,6 @@ void _sched_dl_burst(struct l1sched_trx *l1t, struct trx_dl_burst_req *br) br->burst[i + 88] ^= ks[i + 57]; } } - -no_data: - /* in case of C0, we need a dummy burst to maintain RF power */ - if (!br->burst_len && l1t->trx == l1t->trx->bts->c0) { -#if 0 - if (chan != TRXC_IDLE) // hack - LOGP(DL1C, LOGL_DEBUG, "No burst data for %s fn=%u ts=%u " - "burst=%d on C0, so filling with dummy burst\n", - trx_chan_desc[chan].name, fn, tn, bid); -#endif - memcpy(br->burst, dummy_burst, ARRAY_SIZE(dummy_burst)); - br->burst_len = ARRAY_SIZE(dummy_burst); - } } static int trx_sched_calc_frame_loss(struct l1sched_trx *l1t, diff --git a/src/osmo-bts-trx/scheduler_trx.c b/src/osmo-bts-trx/scheduler_trx.c index 85f0e92f..e6170317 100644 --- a/src/osmo-bts-trx/scheduler_trx.c +++ b/src/osmo-bts-trx/scheduler_trx.c @@ -60,6 +60,7 @@ static void trx_sched_fn(struct gsm_bts *bts, const uint32_t fn) { struct trx_dl_burst_req br; struct gsm_bts_trx *trx; + uint8_t c0_mask = 0x00; uint32_t sched_fn; uint8_t tn; @@ -99,9 +100,31 @@ static void trx_sched_fn(struct gsm_bts *bts, const uint32_t fn) continue; } + /* update dummy burst mask for C0 */ + if (trx == bts->c0) + c0_mask |= (1 << tn); + trx_if_send_burst(l1h, &br); } } + + /* send dummy bursts on inactive timeslots of C0 */ + struct phy_instance *pinst = trx_phy_instance(bts->c0); + struct trx_l1h *l1h = pinst->u.osmotrx.hdl; + struct phy_link *plink = pinst->phy_link; + + br = (struct trx_dl_burst_req) { + .fn = GSM_TDMA_FN_SUM(fn, plink->u.osmotrx.clock_advance), + .burst_len = GSM_BURST_LEN, + }; + + memcpy(br.burst, _sched_dummy_burst, GSM_BURST_LEN); + + for (br.tn = 0; br.tn < TRX_NR_TS; br.tn++) { + if (c0_mask & (1 << br.tn)) + continue; + trx_if_send_burst(l1h, &br); + } } /*! maximum number of 'missed' frame periods we can tolerate of OS doesn't schedule us*/ |