<p>neels has uploaded this change for <strong>review</strong>.</p><p><a href="https://gerrit.osmocom.org/c/osmo-bts/+/22509">View Change</a></p><pre style="font-family: monospace,monospace; white-space: pre-wrap;">chan activ: activate DL SACCH only when TA is known<br><br>A channel activation for handover to another cell does not know the<br>Timing Advance until the handover RACH is received. It does not make<br>much sense to enable downlink SACCH without an accurate TA.<br><br>If the BSC omits the Access Delay IE (a.k.a. the Timing Advance), do not<br>enable downlink SACCH. This is expected to happen only for inter-cell<br>handover. In all other situations, the TA should be known either from a<br>Channel Request RACH for Immediate Assignment, or from the previous<br>lchan on the same cell upon Assignment / intra-cell handover.<br><br>Related: OS#4008 OS#4009 SYS#5192<br>Change-Id: I170b63c9856230d5f1a10654a9d950ada8e730d7<br>---<br>M src/common/rsl.c<br>1 file changed, 14 insertions(+), 2 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/09/22509/1</pre><pre style="font-family: monospace,monospace; white-space: pre-wrap;"><span>diff --git a/src/common/rsl.c b/src/common/rsl.c</span><br><span>index b4df22c..cbd6d41 100644</span><br><span>--- a/src/common/rsl.c</span><br><span>+++ b/src/common/rsl.c</span><br><span>@@ -1545,11 +1545,23 @@</span><br><span> }</span><br><span> </span><br><span> /* Indicate which SAPIs should be enabled before the first RACH is received, for handover. See 3GPP TS 48.058</span><br><span style="color: hsl(0, 100%, 40%);">- * 4.1.3 and 4.1.4. */</span><br><span style="color: hsl(120, 100%, 40%);">+ * 4.1.3 and 4.1.4.</span><br><span style="color: hsl(120, 100%, 40%);">+ *</span><br><span style="color: hsl(120, 100%, 40%);">+ * | | Access || transmit | activate | This implementation</span><br><span style="color: hsl(120, 100%, 40%);">+ * | MS Power | Delay || on main channel | dl SACCH | activates DL SACCH</span><br><span style="color: hsl(120, 100%, 40%);">+ * -----------------------------------------------------------------------------------------</span><br><span style="color: hsl(120, 100%, 40%);">+ * async ho no * --> yes no no</span><br><span style="color: hsl(120, 100%, 40%);">+ * async ho yes * --> yes may be started no</span><br><span style="color: hsl(120, 100%, 40%);">+ * async ho yes yes --> yes may be started yes</span><br><span style="color: hsl(120, 100%, 40%);">+ * sync ho no no --> yes no no</span><br><span style="color: hsl(120, 100%, 40%);">+ * sync ho yes no --> yes may be started no</span><br><span style="color: hsl(120, 100%, 40%);">+ * sync ho yes yes --> yes shall be started yes</span><br><span style="color: hsl(120, 100%, 40%);">+ */</span><br><span> switch (type) {</span><br><span> case RSL_ACT_INTER_ASYNC:</span><br><span> case RSL_ACT_INTER_SYNC:</span><br><span style="color: hsl(0, 100%, 40%);">- lchan->want_dl_sacch_active = TLVP_PRES_LEN(&tp, RSL_IE_MS_POWER, 1);</span><br><span style="color: hsl(120, 100%, 40%);">+ lchan->want_dl_sacch_active = (TLVP_PRES_LEN(&tp, RSL_IE_MS_POWER, 1)</span><br><span style="color: hsl(120, 100%, 40%);">+ && TLVP_PRES_LEN(&tp, RSL_IE_ACCESS_DELAY, 1))</span><br><span> break;</span><br><span> default:</span><br><span> lchan->want_dl_sacch_active = true;</span><br><span></span><br></pre><p>To view, visit <a href="https://gerrit.osmocom.org/c/osmo-bts/+/22509">change 22509</a>. To unsubscribe, or for help writing mail filters, visit <a href="https://gerrit.osmocom.org/settings">settings</a>.</p><div itemscope itemtype="http://schema.org/EmailMessage"><div itemscope itemprop="action" itemtype="http://schema.org/ViewAction"><link itemprop="url" href="https://gerrit.osmocom.org/c/osmo-bts/+/22509"/><meta itemprop="name" content="View Change"/></div></div>
<div style="display:none"> Gerrit-Project: osmo-bts </div>
<div style="display:none"> Gerrit-Branch: master </div>
<div style="display:none"> Gerrit-Change-Id: I170b63c9856230d5f1a10654a9d950ada8e730d7 </div>
<div style="display:none"> Gerrit-Change-Number: 22509 </div>
<div style="display:none"> Gerrit-PatchSet: 1 </div>
<div style="display:none"> Gerrit-Owner: neels <nhofmeyr@sysmocom.de> </div>
<div style="display:none"> Gerrit-MessageType: newchange </div>