<p>dexter has uploaded this change for <strong>review</strong>.</p><p><a href="https://gerrit.osmocom.org/c/osmo-bts/+/21105">View Change</a></p><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>Depends: libosmocore I61ea6bf54ea90bd69b73ea0f0f3dc19a4214207b<br>Change-Id: I00806f936b15fbaf6a4e7bbd61f3bec262cdbb28<br>Related: OS#4794, SYS#5114<br>---<br>M include/osmo-bts/bts.h<br>M include/osmo-bts/gsm_data.h<br>M src/common/l1sap.c<br>M src/common/rsl.c<br>M src/common/vty.c<br>5 files changed, 77 insertions(+), 3 deletions(-)<br><br></pre><pre style="font-family: monospace,monospace; white-space: pre-wrap;">git pull ssh://gerrit.osmocom.org:29418/osmo-bts refs/changes/05/21105/1</pre><pre style="font-family: monospace,monospace; white-space: pre-wrap;"><span>diff --git a/include/osmo-bts/bts.h b/include/osmo-bts/bts.h</span><br><span>index fdcc67b..950551c 100644</span><br><span>--- a/include/osmo-bts/bts.h</span><br><span>+++ b/include/osmo-bts/bts.h</span><br><span>@@ -341,6 +341,9 @@</span><br><span> /* 3GPP TS 44.006, section 10, Repeated Downlink FACCH */</span><br><span> bool facch_repetition_enabled;</span><br><span> </span><br><span style="color: hsl(120, 100%, 40%);">+ /* 3GPP TS 44.006, section 11.2, Procedure for Repeated SACCH on the downlink */</span><br><span style="color: hsl(120, 100%, 40%);">+ bool dl_sacch_repetition_enabled;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span> void *model_priv; /* Allocated by bts_model, contains model specific data pointer */</span><br><span> };</span><br><span> </span><br><span>diff --git a/include/osmo-bts/gsm_data.h b/include/osmo-bts/gsm_data.h</span><br><span>index 59fd809..2441286 100644</span><br><span>--- a/include/osmo-bts/gsm_data.h</span><br><span>+++ b/include/osmo-bts/gsm_data.h</span><br><span>@@ -264,6 +264,7 @@</span><br><span> </span><br><span> /* SLOT #0 and #1 to store FACCH for repetition */</span><br><span> struct gsm_rep_facch rep_facch[2];</span><br><span style="color: hsl(120, 100%, 40%);">+ struct msgb *rep_sacch;</span><br><span> </span><br><span> } tch;</span><br><span> </span><br><span>diff --git a/src/common/l1sap.c b/src/common/l1sap.c</span><br><span>index 6001b9f..30f226a 100644</span><br><span>--- a/src/common/l1sap.c</span><br><span>+++ b/src/common/l1sap.c</span><br><span>@@ -964,6 +964,44 @@</span><br><span> return msg;</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%);">+ /* SACCH repetition disabled by the MS */</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 pending repetition candidate */</span><br><span style="color: hsl(120, 100%, 40%);">+ if (lchan->tch.rep_sacch)</span><br><span style="color: hsl(120, 100%, 40%);">+ msgb_free(lchan->tch.rep_sacch);</span><br><span style="color: hsl(120, 100%, 40%);">+ lchan->tch.rep_sacch = NULL;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ /* Fetch new FACCH from queue normally */</span><br><span style="color: hsl(120, 100%, 40%);">+ return lapdm_phsap_dequeue_msg(le);</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%);">+ /* Repeat pending candidate */</span><br><span style="color: hsl(120, 100%, 40%);">+ if (lchan->tch.rep_sacch) {</span><br><span style="color: hsl(120, 100%, 40%);">+ msg = lchan->tch.rep_sacch;</span><br><span style="color: hsl(120, 100%, 40%);">+ lchan->tch.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%);">+ /* Fetch new SACCH 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%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ /* Only SAPI 0 SACCH frames are repetition candidates, see also 3GPP TS 44.006, section 11.2 */</span><br><span style="color: hsl(120, 100%, 40%);">+ sapi = (msg->data[0] >> 2) & 0x07;</span><br><span style="color: hsl(120, 100%, 40%);">+ if (sapi == 0)</span><br><span style="color: hsl(120, 100%, 40%);">+ lchan->tch.rep_sacch = msg;</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>@@ -1044,7 +1082,10 @@</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->ts->trx->bts->dl_sacch_repetition_enabled)</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 16109b2..26560b9 100644</span><br><span>--- a/src/common/rsl.c</span><br><span>+++ b/src/common/rsl.c</span><br><span>@@ -823,13 +823,16 @@</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> if (lchan->tch.rep_facch[0].msg)</span><br><span> msgb_free(lchan->tch.rep_facch[0].msg);</span><br><span> if (lchan->tch.rep_facch[1].msg)</span><br><span> msgb_free(lchan->tch.rep_facch[1].msg);</span><br><span> memset(lchan->tch.rep_facch, 0, sizeof(lchan->tch.rep_facch));</span><br><span style="color: hsl(120, 100%, 40%);">+ if(lchan->tch.rep_sacch)</span><br><span style="color: hsl(120, 100%, 40%);">+ msgb_free(lchan->tch.rep_sacch);</span><br><span style="color: hsl(120, 100%, 40%);">+ lchan->tch.rep_sacch = NULL;</span><br><span> </span><br><span> return tx_rf_rel_ack(lchan, chan_nr);</span><br><span> }</span><br><span>diff --git a/src/common/vty.c b/src/common/vty.c</span><br><span>index 59a6dee..f8033df 100644</span><br><span>--- a/src/common/vty.c</span><br><span>+++ b/src/common/vty.c</span><br><span>@@ -307,6 +307,8 @@</span><br><span> vty_out(vty, " smscb queue-hysteresis %d%s", bts->smscb_queue_hyst, VTY_NEWLINE);</span><br><span> if (bts->facch_repetition_enabled)</span><br><span> vty_out(vty, " facch-repetition%s", VTY_NEWLINE);</span><br><span style="color: hsl(120, 100%, 40%);">+ if (bts->dl_sacch_repetition_enabled)</span><br><span style="color: hsl(120, 100%, 40%);">+ vty_out(vty, " sacch-repetition%s", VTY_NEWLINE);</span><br><span> </span><br><span> bts_model_config_write_bts(vty, bts);</span><br><span> </span><br><span>@@ -823,6 +825,28 @@</span><br><span> return CMD_SUCCESS;</span><br><span> }</span><br><span> </span><br><span style="color: hsl(120, 100%, 40%);">+DEFUN_ATTR(cfg_bts_dl_sacch_repetition, cfg_bts_dl_sacch_repetition_cmd,</span><br><span style="color: hsl(120, 100%, 40%);">+ "dl-sacch-repetition",</span><br><span style="color: hsl(120, 100%, 40%);">+ "enable downlink SACCH repetition\n",</span><br><span style="color: hsl(120, 100%, 40%);">+ CMD_ATTR_IMMEDIATE)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ struct gsm_bts *bts = vty->index;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ bts->dl_sacch_repetition_enabled = true;</span><br><span style="color: hsl(120, 100%, 40%);">+ return CMD_SUCCESS;</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%);">+DEFUN_ATTR(cfg_bts_no_dl_sacch_repetition, cfg_bts_no_dl_sacch_repetition_cmd,</span><br><span style="color: hsl(120, 100%, 40%);">+ "no dl-sacch-repetition",</span><br><span style="color: hsl(120, 100%, 40%);">+ NO_STR "disable downlink SACCH repetition\n",</span><br><span style="color: hsl(120, 100%, 40%);">+ CMD_ATTR_IMMEDIATE)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ struct gsm_bts *bts = vty->index;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ bts->dl_sacch_repetition_enabled = false;</span><br><span style="color: hsl(120, 100%, 40%);">+ return CMD_SUCCESS;</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span> #define DB_MDB_STR \</span><br><span> "Unit is dB (decibels)\n" \</span><br><span> "Unit is mdB (milli-decibels, or rather 1/10000 bel)\n"</span><br><span>@@ -1917,6 +1941,8 @@</span><br><span> install_element(BTS_NODE, &cfg_bts_smscb_qhyst_cmd);</span><br><span> install_element(BTS_NODE, &cfg_bts_facch_repetition_cmd);</span><br><span> install_element(BTS_NODE, &cfg_bts_no_facch_repetition_cmd);</span><br><span style="color: hsl(120, 100%, 40%);">+ install_element(BTS_NODE, &cfg_bts_dl_sacch_repetition_cmd);</span><br><span style="color: hsl(120, 100%, 40%);">+ install_element(BTS_NODE, &cfg_bts_no_dl_sacch_repetition_cmd);</span><br><span> </span><br><span> install_element(BTS_NODE, &cfg_trx_gsmtap_sapi_all_cmd);</span><br><span> install_element(BTS_NODE, &cfg_trx_gsmtap_sapi_cmd);</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: 1 </div>
<div style="display:none"> Gerrit-Owner: dexter <pmaier@sysmocom.de> </div>
<div style="display:none"> Gerrit-MessageType: newchange </div>