Review at https://gerrit.osmocom.org/4678
LC15: Fix TA adjustment
Change-Id: I65212f8203f1a35278890f51db038d689b2493d5
---
M src/bts.cpp
M src/bts.h
M src/osmo-bts-litecell15/lc15_l1_if.c
M src/pcu_l1_if.h
4 files changed, 57 insertions(+), 11 deletions(-)
git pull ssh://gerrit.osmocom.org:29418/osmo-pcu refs/changes/78/4678/1
diff --git a/src/bts.cpp b/src/bts.cpp
index e41b1fa..7ffb132 100644
--- a/src/bts.cpp
+++ b/src/bts.cpp
@@ -1619,20 +1619,48 @@
return rc;
}
-void bts_update_tbf_ta(const char *p, uint32_t fn, uint8_t trx_no, uint8_t ts,
- uint8_t ta)
+void bts_update_tbf_ta(const char *p, uint32_t fn, uint8_t trx_no, uint8_t ts,
int8_t ta)
{
+ int ta_final;
+ bool need_update = false;
+
struct gprs_rlcmac_ul_tbf *tbf =
bts_main_data()->bts->ul_tbf_by_poll_fn(fn, trx_no, ts);
if (!tbf)
LOGP(DL1IF, LOGL_DEBUG, "[%s] update TA = %u ignored due to "
"unknown UL TBF on TRX = %d, TS = %d, FN = %d\n",
p, ta, trx_no, ts, fn);
- else if (tbf->ta() != ta) {
- LOGP(DL1IF, LOGL_INFO, "[%s] Updating TA %u -> %u on "
- "TRX = %d, TS = %d, FN = %d\n",
- p, tbf->ta(), ta, trx_no, ts, fn);
- tbf->set_ta(ta);
+ else {
+ /* we need to distinguish TA information provided by L1
+ * from PH-DATA-IND and PHY-RA-IND so that we can properly
+ * update TA for given TBF
+ */
+ if (!strcmp(p, "PH-DATA")) {
+ if (ta) {
+ /* adjust TA based on TA provided by
PH-DATA-IND */
+ ta_final = tbf->ta() + ta;
+ need_update = true;
+ }
+ } else if ((!strcmp(p, "PH-RA"))) {
+ if (tbf->ta() != ta) {
+ /* adjust TA based on TA provided by PH-RA-IND
*/
+ ta_final = ta;
+ need_update = true;
+ }
+ }
+
+ if (need_update) {
+ /* limit TA range is between 0 and 63 bits */
+ if (ta_final < 0)
+ ta_final = 0;
+ else if (ta_final > 63)
+ ta_final = 63;
+
+ LOGP(DL1IF, LOGL_INFO, "[%s] Updating TLLI=0x%08x: TA
%u -> %u on "
+ "TRX = %d, TS = %d, FN = %d\n",
+ p, tbf->tlli(), tbf->ta(), ta_final, trx_no,
ts, fn);
+ tbf->set_ta((uint8_t)ta_final);
+ }
}
}
diff --git a/src/bts.h b/src/bts.h
index d65cd2f..139aeae 100644
--- a/src/bts.h
+++ b/src/bts.h
@@ -162,8 +162,7 @@
#ifdef __cplusplus
extern "C" {
#endif
-void bts_update_tbf_ta(const char *p, uint32_t fn, uint8_t trx_no, uint8_t ts,
- uint8_t ta);
+void bts_update_tbf_ta(const char *p, uint32_t fn, uint8_t trx_no, uint8_t ts,
int8_t ta);
#ifdef __cplusplus
}
#endif
diff --git a/src/osmo-bts-litecell15/lc15_l1_if.c
b/src/osmo-bts-litecell15/lc15_l1_if.c
index 37b7f78..628bd3d 100644
--- a/src/osmo-bts-litecell15/lc15_l1_if.c
+++ b/src/osmo-bts-litecell15/lc15_l1_if.c
@@ -203,7 +203,7 @@
get_meas(&meas, &data_ind->measParam);
bts_update_tbf_ta("PH-DATA", data_ind->u32Fn, fl1h->trx_no,
- data_ind->u8Tn, qta2ta(meas.bto));
+ data_ind->u8Tn, sign_qta2ta(meas.bto));
switch (data_ind->sapi) {
case GsmL1_Sapi_Pdtch:
@@ -248,7 +248,7 @@
DEBUGP(DL1IF, "Rx PH-RA.ind");
bts_update_tbf_ta("PH-RA", ra_ind->u32Fn, fl1h->trx_no, ra_ind->u8Tn,
- qta2ta(ra_ind->measParam.i16BurstTiming));
+ sign_qta2ta(ra_ind->measParam.i16BurstTiming));
return 0;
}
diff --git a/src/pcu_l1_if.h b/src/pcu_l1_if.h
index 1618260..af51693 100644
--- a/src/pcu_l1_if.h
+++ b/src/pcu_l1_if.h
@@ -43,6 +43,25 @@
return qta >> 2;
}
+static inline int8_t sign_qta2ta(int16_t qta)
+{
+ int8_t ta_adj = 0;
+
+ if (qta < -252)
+ qta = -252;
+
+ if (qta > 252)
+ qta = 252;
+
+ /* 1-bit TA adjustment if TA error reported by L1 is higher outside
+/- 2 qbits */
+ if (qta > 2)
+ ta_adj = 1;
+ if (qta < -2)
+ ta_adj = -1;
+
+ return (qta >> 2) + ta_adj;
+}
+
/*
* L1 Measurement values
*/
--
To view, visit https://gerrit.osmocom.org/4678
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Gerrit-MessageType: newchange
Gerrit-Change-Id: I65212f8203f1a35278890f51db038d689b2493d5
Gerrit-PatchSet: 1
Gerrit-Project: osmo-pcu
Gerrit-Branch: master
Gerrit-Owner: Minh-Quang Nguyen <[email protected]>
