[handover] first functional handover implementation
With this commit, we can successfully hand over a channel from one cell to
another cell. We implement asynchronous intra-BSC (but inter-BTS) handover.
Changes:
* introduce new DHO log category
* extend rsl_chan_activate_lchan() with argument for HO reference
* introduce actual minimal handover decision making in handover_decision.c
* various fixes to bsc_handover_start() in handover_logic.c
diff --git a/openbsc/src/abis_rsl.c b/openbsc/src/abis_rsl.c
index 1fbea83..d42daf5 100644
--- a/openbsc/src/abis_rsl.c
+++ b/openbsc/src/abis_rsl.c
@@ -576,7 +576,7 @@
#endif
int rsl_chan_activate_lchan(struct gsm_lchan *lchan, u_int8_t act_type,
- u_int8_t ta)
+ u_int8_t ta, u_int8_t ho_ref)
{
struct abis_rsl_dchan_hdr *dh;
struct msgb *msg;
@@ -603,9 +603,9 @@
dh->chan_nr = chan_nr;
msgb_tv_put(msg, RSL_IE_ACT_TYPE, act_type);
- /* For compatibility with Phase 1 */
msgb_tlv_put(msg, RSL_IE_CHAN_MODE, sizeof(cm),
(u_int8_t *) &cm);
+ /* For compatibility with Phase 1 */
msgb_tlv_put(msg, RSL_IE_CHAN_IDENT, 4,
(u_int8_t *) &ci);
@@ -616,6 +616,15 @@
msgb_tlv_put(msg, RSL_IE_ENCR_INFO, rc, encr_info);
}
+ switch (act_type) {
+ case RSL_ACT_INTER_ASYNC:
+ case RSL_ACT_INTER_SYNC:
+ msgb_tv_put(msg, RSL_IE_HANDO_REF, ho_ref);
+ break;
+ default:
+ break;
+ }
+
msgb_tv_put(msg, RSL_IE_BS_POWER, lchan->bs_power);
msgb_tv_put(msg, RSL_IE_MS_POWER, lchan->ms_power);
msgb_tv_put(msg, RSL_IE_TIMING_ADVANCE, ta);
@@ -1258,7 +1267,7 @@
lchan->bs_power = 0; /* 0dB reduction, output power = Pn */
lchan->rsl_cmode = RSL_CMOD_SPD_SIGN;
lchan->tch_mode = GSM48_CMODE_SIGN;
- rsl_chan_activate_lchan(lchan, 0x00, rqd_ta);
+ rsl_chan_activate_lchan(lchan, 0x00, rqd_ta, 0);
/* create IMMEDIATE ASSIGN 04.08 messge */
memset(&ia, 0, sizeof(ia));