osmo-bts-trx: introduce and use struct trx_dl_burst_req

This change is similar to what we did for Uplink bursts:

  - group all Downlink burst parameters into a single structure,
  - allocate it once and pass a pointer to lchan handlers,
  - pass a pointer to trx_if_send_burst().

Given that the structure is allocated and (zero-)initialized in
trx_sched_fn(), we can get rid of some memset() calls in lchan
handlers and thus improve the overall performance a bit.

Change-Id: If3014e69746559963569b77561dbf7b163c68ffa

2 files changed, 29 insertions, 19 deletions

diff --git a/include/osmo-bts/scheduler.h b/include/osmo-bts/scheduler.h
index 74102f32..a7bc6c72 100644
--- a/include/osmo-bts/scheduler.h
+++ b/include/osmo-bts/scheduler.h
@@ -250,6 +250,17 @@ struct trx_ul_burst_ind {
 	size_t burst_len;
 };
 
+/*! DL burst request with the corresponding meta info */
+struct trx_dl_burst_req {
+	uint32_t fn;		/*!< TDMA frame number */
+	uint8_t tn;		/*!< TDMA timeslot number */
+	uint8_t att;		/*!< Tx power attenuation */
+
+	/*! Burst hard-bits buffer */
+	ubit_t burst[EGPRS_BURST_LEN];
+	size_t burst_len;
+};
+
 /*! Handle an UL burst received by PHY */
 int trx_sched_ul_burst(struct l1sched_trx *l1t, struct trx_ul_burst_ind *bi);
 
diff --git a/include/osmo-bts/scheduler_backend.h b/include/osmo-bts/scheduler_backend.h
index cfbe7f25..be23c474 100644
--- a/include/osmo-bts/scheduler_backend.h
+++ b/include/osmo-bts/scheduler_backend.h
@@ -9,9 +9,8 @@
 typedef int trx_sched_rts_func(struct l1sched_trx *l1t, uint8_t tn,
 			       uint32_t fn, enum trx_chan_type chan);
 
-typedef ubit_t *trx_sched_dl_func(struct l1sched_trx *l1t, uint8_t tn,
-				  uint32_t fn, enum trx_chan_type chan,
-				  uint8_t bid, uint16_t *nbits);
+typedef int trx_sched_dl_func(struct l1sched_trx *l1t, enum trx_chan_type chan,
+			      uint8_t bid, struct trx_dl_burst_req *br);
 
 typedef int trx_sched_ul_func(struct l1sched_trx *l1t, enum trx_chan_type chan,
 			      uint8_t bid, const struct trx_ul_burst_ind *bi);
@@ -56,20 +55,21 @@ int _sched_compose_tch_ind(struct l1sched_trx *l1t, uint8_t tn, uint32_t fn,
 			   int16_t ta_offs_256bits, uint16_t ber10k, float rssi,
 			   uint8_t is_sub);
 
-ubit_t *tx_idle_fn(struct l1sched_trx *l1t, uint8_t tn, uint32_t fn,
-	enum trx_chan_type chan, uint8_t bid, uint16_t *nbits);
-ubit_t *tx_fcch_fn(struct l1sched_trx *l1t, uint8_t tn, uint32_t fn,
-	enum trx_chan_type chan, uint8_t bid, uint16_t *nbits);
-ubit_t *tx_sch_fn(struct l1sched_trx *l1t, uint8_t tn, uint32_t fn,
-	enum trx_chan_type chan, uint8_t bid, uint16_t *nbits);
-ubit_t *tx_data_fn(struct l1sched_trx *l1t, uint8_t tn, uint32_t fn,
-	enum trx_chan_type chan, uint8_t bid, uint16_t *nbits);
-ubit_t *tx_pdtch_fn(struct l1sched_trx *l1t, uint8_t tn, uint32_t fn,
-	enum trx_chan_type chan, uint8_t bid, uint16_t *nbits);
-ubit_t *tx_tchf_fn(struct l1sched_trx *l1t, uint8_t tn, uint32_t fn,
-	enum trx_chan_type chan, uint8_t bid, uint16_t *nbits);
-ubit_t *tx_tchh_fn(struct l1sched_trx *l1t, uint8_t tn, uint32_t fn,
-	enum trx_chan_type chan, uint8_t bid, uint16_t *nbits);
+int tx_idle_fn(struct l1sched_trx *l1t, enum trx_chan_type chan,
+	       uint8_t bid, struct trx_dl_burst_req *br);
+int tx_fcch_fn(struct l1sched_trx *l1t, enum trx_chan_type chan,
+	       uint8_t bid, struct trx_dl_burst_req *br);
+int tx_sch_fn(struct l1sched_trx *l1t, enum trx_chan_type chan,
+	       uint8_t bid, struct trx_dl_burst_req *br);
+int tx_data_fn(struct l1sched_trx *l1t, enum trx_chan_type chan,
+	       uint8_t bid, struct trx_dl_burst_req *br);
+int tx_pdtch_fn(struct l1sched_trx *l1t, enum trx_chan_type chan,
+	       uint8_t bid, struct trx_dl_burst_req *br);
+int tx_tchf_fn(struct l1sched_trx *l1t, enum trx_chan_type chan,
+	       uint8_t bid, struct trx_dl_burst_req *br);
+int tx_tchh_fn(struct l1sched_trx *l1t, enum trx_chan_type chan,
+	       uint8_t bid, struct trx_dl_burst_req *br);
+
 int rx_rach_fn(struct l1sched_trx *l1t, enum trx_chan_type chan,
 	       uint8_t bid, const struct trx_ul_burst_ind *bi);
 int rx_data_fn(struct l1sched_trx *l1t, enum trx_chan_type chan,
@@ -81,7 +81,6 @@ int rx_tchf_fn(struct l1sched_trx *l1t, enum trx_chan_type chan,
 int rx_tchh_fn(struct l1sched_trx *l1t, enum trx_chan_type chan,
 	       uint8_t bid, const struct trx_ul_burst_ind *bi);
 
-const ubit_t *_sched_dl_burst(struct l1sched_trx *l1t, uint8_t tn,
-			      uint32_t fn, uint16_t *nbits);
+void _sched_dl_burst(struct l1sched_trx *l1t, struct trx_dl_burst_req *br);
 int _sched_rts(struct l1sched_trx *l1t, uint8_t tn, uint32_t fn);
 void _sched_act_rach_det(struct l1sched_trx *l1t, uint8_t tn, uint8_t ss, int activate);