<p>laforge <strong>submitted</strong> this change.</p><p><a href="https://gerrit.osmocom.org/c/osmo-bts/+/21105">View Change</a></p><div style="white-space:pre-wrap">Approvals:
Jenkins Builder: Verified
pespin: Looks good to me, but someone else must approve
fixeria: Looks good to me, approved
</div><pre style="font-family: monospace,monospace; white-space: pre-wrap;">l1sap: add repeated downlink SACCH<br><br>3GPP TS 44.006, section 11 describes a method how the downlink<br>SACCH transmission can be repeated to increase transmission<br>reliability.<br><br>Change-Id: I00806f936b15fbaf6a4e7bbd61f3bec262cdbb28<br>Related: OS#4794, SYS#5114<br>---<br>M include/osmo-bts/gsm_data.h<br>M src/common/l1sap.c<br>M src/common/rsl.c<br>3 files changed, 49 insertions(+), 3 deletions(-)<br><br></pre><pre style="font-family: monospace,monospace; white-space: pre-wrap;"><span>diff --git a/include/osmo-bts/gsm_data.h b/include/osmo-bts/gsm_data.h</span><br><span>index 47a6db8..b5b616e 100644</span><br><span>--- a/include/osmo-bts/gsm_data.h</span><br><span>+++ b/include/osmo-bts/gsm_data.h</span><br><span>@@ -326,6 +326,9 @@</span><br><span> </span><br><span> struct abis_rsl_osmo_rep_acch_cap repeated_acch_capability;</span><br><span> bool repeated_dl_facch_active;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ /* Message buffer to store DL-SACCH repeation candidate */</span><br><span style="color: hsl(120, 100%, 40%);">+ struct msgb *rep_sacch;</span><br><span> };</span><br><span> </span><br><span> static inline uint8_t lchan_get_ta(const struct gsm_lchan *lchan)</span><br><span>diff --git a/src/common/l1sap.c b/src/common/l1sap.c</span><br><span>index 3c45b62..05adbb1 100644</span><br><span>--- a/src/common/l1sap.c</span><br><span>+++ b/src/common/l1sap.c</span><br><span>@@ -1014,6 +1014,44 @@</span><br><span> lchan->repeated_dl_facch_active = false;</span><br><span> }</span><br><span> </span><br><span style="color: hsl(120, 100%, 40%);">+/* Special dequeueing function with SACCH repetition (3GPP TS 44.006, section 11) */</span><br><span style="color: hsl(120, 100%, 40%);">+static inline struct msgb *lapdm_phsap_dequeue_msg_sacch(struct gsm_lchan *lchan, struct lapdm_entity *le)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ struct osmo_phsap_prim pp;</span><br><span style="color: hsl(120, 100%, 40%);">+ struct msgb *msg;</span><br><span style="color: hsl(120, 100%, 40%);">+ uint8_t sapi;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ /* Note: When the MS disables SACCH repetition, we still must collect</span><br><span style="color: hsl(120, 100%, 40%);">+ * possible candidates in order to have one ready in case the MS enables</span><br><span style="color: hsl(120, 100%, 40%);">+ * SACCH repetition. */</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ if (lchan->rep_sacch) {</span><br><span style="color: hsl(120, 100%, 40%);">+ if (((lchan->meas.l1_info[0] >> 1) & 1) == 0) {</span><br><span style="color: hsl(120, 100%, 40%);">+ /* Toss previous repetition candidate */</span><br><span style="color: hsl(120, 100%, 40%);">+ msgb_free(lchan->rep_sacch);</span><br><span style="color: hsl(120, 100%, 40%);">+ lchan->rep_sacch = NULL;</span><br><span style="color: hsl(120, 100%, 40%);">+ } else {</span><br><span style="color: hsl(120, 100%, 40%);">+ /* Use previous repetition candidate */</span><br><span style="color: hsl(120, 100%, 40%);">+ msg = lchan->rep_sacch;</span><br><span style="color: hsl(120, 100%, 40%);">+ lchan->rep_sacch = NULL;</span><br><span style="color: hsl(120, 100%, 40%);">+ return msg;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ /* Fetch new repetition candidate from queue */</span><br><span style="color: hsl(120, 100%, 40%);">+ if (lapdm_phsap_dequeue_prim(le, &pp) < 0)</span><br><span style="color: hsl(120, 100%, 40%);">+ return NULL;</span><br><span style="color: hsl(120, 100%, 40%);">+ msg = pp.oph.msg;</span><br><span style="color: hsl(120, 100%, 40%);">+ sapi = (msg->data[0] >> 2) & 0x07;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ /* Only LAPDm frames for SAPI may become a repetition</span><br><span style="color: hsl(120, 100%, 40%);">+ * candidate. */</span><br><span style="color: hsl(120, 100%, 40%);">+ if (sapi == 0)</span><br><span style="color: hsl(120, 100%, 40%);">+ lchan->rep_sacch = msgb_copy(msg, "rep_sacch");</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ return msg;</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span> /* PH-RTS-IND prim received from bts model */</span><br><span> static int l1sap_ph_rts_ind(struct gsm_bts_trx *trx,</span><br><span> struct osmo_phsap_prim *l1sap, struct ph_data_param *rts_ind)</span><br><span>@@ -1095,7 +1133,10 @@</span><br><span> p[0] = lchan->ms_power_ctrl.current;</span><br><span> p[1] = lchan->rqd_ta;</span><br><span> le = &lchan->lapdm_ch.lapdm_acch;</span><br><span style="color: hsl(0, 100%, 40%);">- pp_msg = lapdm_phsap_dequeue_msg(le);</span><br><span style="color: hsl(120, 100%, 40%);">+ if (lchan->repeated_acch_capability.dl_sacch)</span><br><span style="color: hsl(120, 100%, 40%);">+ pp_msg = lapdm_phsap_dequeue_msg_sacch(lchan, le);</span><br><span style="color: hsl(120, 100%, 40%);">+ else</span><br><span style="color: hsl(120, 100%, 40%);">+ pp_msg = lapdm_phsap_dequeue_msg(le);</span><br><span> } else {</span><br><span> if (lchan->ts->trx->bts->dtxd)</span><br><span> dtxd_facch = true;</span><br><span>diff --git a/src/common/rsl.c b/src/common/rsl.c</span><br><span>index 14a0dcc..8760c24 100644</span><br><span>--- a/src/common/rsl.c</span><br><span>+++ b/src/common/rsl.c</span><br><span>@@ -823,12 +823,14 @@</span><br><span> */</span><br><span> lapdm_channel_exit(&lchan->lapdm_ch);</span><br><span> </span><br><span style="color: hsl(0, 100%, 40%);">- /* Also ensure that there are no leftovers from repeated FACCH</span><br><span style="color: hsl(0, 100%, 40%);">- * that might cause memory leakage. */</span><br><span style="color: hsl(120, 100%, 40%);">+ /* Also ensure that there are no leftovers from repeated FACCH or</span><br><span style="color: hsl(120, 100%, 40%);">+ * repeated SACCH that might cause memory leakage. */</span><br><span> msgb_free(lchan->tch.rep_facch[0].msg);</span><br><span> msgb_free(lchan->tch.rep_facch[1].msg);</span><br><span> lchan->tch.rep_facch[0].msg = NULL;</span><br><span> lchan->tch.rep_facch[1].msg = NULL;</span><br><span style="color: hsl(120, 100%, 40%);">+ msgb_free(lchan->rep_sacch);</span><br><span style="color: hsl(120, 100%, 40%);">+ lchan->rep_sacch = NULL;</span><br><span> </span><br><span> return tx_rf_rel_ack(lchan, chan_nr);</span><br><span> }</span><br><span></span><br></pre><p>To view, visit <a href="https://gerrit.osmocom.org/c/osmo-bts/+/21105">change 21105</a>. 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<div style="display:none"> Gerrit-Project: osmo-bts </div>
<div style="display:none"> Gerrit-Branch: master </div>
<div style="display:none"> Gerrit-Change-Id: I00806f936b15fbaf6a4e7bbd61f3bec262cdbb28 </div>
<div style="display:none"> Gerrit-Change-Number: 21105 </div>
<div style="display:none"> Gerrit-PatchSet: 7 </div>
<div style="display:none"> Gerrit-Owner: dexter <pmaier@sysmocom.de> </div>
<div style="display:none"> Gerrit-Reviewer: Jenkins Builder </div>
<div style="display:none"> Gerrit-Reviewer: fixeria <vyanitskiy@sysmocom.de> </div>
<div style="display:none"> Gerrit-Reviewer: laforge <laforge@osmocom.org> </div>
<div style="display:none"> Gerrit-Reviewer: pespin <pespin@sysmocom.de> </div>
<div style="display:none"> Gerrit-MessageType: merged </div>