Change in osmo-pcu[master]: PTCCH: skip Tx DL idle blocks when possible

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pespin gerrit-no-reply at
Mon Sep 20 17:31:45 UTC 2021

pespin has submitted this change. ( )

Change subject: PTCCH: skip Tx DL idle blocks when possible

PTCCH: skip Tx DL idle blocks when possible

Same was already done for PDTCH in previous commits. Let's now apply
same bits to PTCCH.

Related: SYS#4919
Change-Id: If6617964e67fc35eeee1791b06e13bf63ac88f73
M src/pcu_l1_if.cpp
1 file changed, 16 insertions(+), 0 deletions(-)

  osmith: Looks good to me, but someone else must approve
  fixeria: Looks good to me, but someone else must approve
  pespin: Looks good to me, approved
  Jenkins Builder: Verified

diff --git a/src/pcu_l1_if.cpp b/src/pcu_l1_if.cpp
index 25c1933..1600da0 100644
--- a/src/pcu_l1_if.cpp
+++ b/src/pcu_l1_if.cpp
@@ -531,6 +531,22 @@
 	if (!pdch->m_is_enabled)
 		return -EAGAIN;
+	/* If there's no TBF attached to this PDCH, we can skip Tx of PTCCH
+	 * since there's nothing worthy of being transmitted. This way BTS can
+	 * identify idle blocks and send nothing or dumy blocks with reduced
+	 * energy for the sake of energy saving.
+	 */
+	const unsigned num_tbfs = pdch->num_tbfs(GPRS_RLCMAC_DL_TBF)
+				+ pdch->num_tbfs(GPRS_RLCMAC_UL_TBF);
+	bool skip_idle = (num_tbfs == 0);
+		/* In DIRECT_PHY mode we want to always submit something to L1 in
+		 * TRX0, since BTS is not preparing dummy bursts on idle TS for us: */
+		skip_idle = skip_idle && trx != 0;
+	if (skip_idle)
+		return 0;
 	pcu_l1if_tx_ptcch(bts, trx, ts, bts->trx[trx].arfcn, fn, block_nr,
 			  pdch->ptcch_msg, GSM_MACBLOCK_LEN);
 	return 0;

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Gerrit-Project: osmo-pcu
Gerrit-Branch: master
Gerrit-Change-Id: If6617964e67fc35eeee1791b06e13bf63ac88f73
Gerrit-Change-Number: 25509
Gerrit-PatchSet: 1
Gerrit-Owner: pespin <pespin at>
Gerrit-Reviewer: Jenkins Builder
Gerrit-Reviewer: fixeria <vyanitskiy at>
Gerrit-Reviewer: osmith <osmith at>
Gerrit-Reviewer: pespin <pespin at>
Gerrit-MessageType: merged
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