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- Lower severity on expert items about Timing Advance if <= 31 

- Detect original frame for DL HARQ retx also 9 SFs ago (have even seen 10...)
- Getting ready to log 'grant subframe' for UL frames (only interesting for TDD)

svn path=/trunk/; revision=32538
This commit is contained in:
Martin Mathieson 2010-04-22 13:54:30 +00:00
parent ea392ce83d
commit 5a39a9ef39
1 changed files with 46 additions and 26 deletions
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72
epan/dissectors/packet-mac-lte.c
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@ -59,6 +59,7 @@ static int hf_mac_lte_context_rnti = -1;
static int hf_mac_lte_context_rnti_type = -1;
static int hf_mac_lte_context_ueid = -1;
static int hf_mac_lte_context_subframe_number = -1;
static int hf_mac_lte_context_grant_subframe_number = -1;
static int hf_mac_lte_context_predefined_frame = -1;
static int hf_mac_lte_context_length = -1;
static int hf_mac_lte_context_ul_grant_size = -1;
@ -1125,7 +1126,7 @@ static gint dissect_rar_entry(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tre
timing_advance = (tvb_get_ntohs(tvb, offset) & 0x7ff0) >> 4;
ti = proto_tree_add_item(rar_body_tree, hf_mac_lte_rar_ta, tvb, offset, 2, FALSE);
if (timing_advance != 0) {
expert_add_info_format(pinfo, ti, PI_SEQUENCE, PI_WARN,
expert_add_info_format(pinfo, ti, PI_SEQUENCE, (timing_advance <= 31) ? PI_NOTE : PI_WARN,
"RAR Timing advance not zero (%u)", timing_advance);
}
offset++;
@ -1550,31 +1551,41 @@ static int DetectIfDLHARQResend(packet_info *pinfo, tvbuff_t *tvb, volatile int
LastFrameDataAllSubframes *ueData =
g_hash_table_lookup(mac_lte_dl_harq_hash, GUINT_TO_POINTER((guint)p_mac_lte_info->rnti));
if (ueData != NULL) {
/* Looking for a frame sent 8 subframes previously */
lastData = &(ueData->subframe[(p_mac_lte_info->subframeNumber+2) % 10]);
if (lastData->inUse) {
/* Compare time, sf, data to see if this looks like a retx */
if ((tvb_length_remaining(tvb, offset) == lastData->length) &&
(memcmp(lastData->data,
tvb_get_ptr(tvb, offset, lastData->length),
MIN(lastData->length, MAX_EXPECTED_PDU_LENGTH)) == 0)) {
/* Work out gap between frames */
gint seconds_between_packets = (gint)
(pinfo->fd->abs_ts.secs - lastData->received_time.secs);
gint nseconds_between_packets =
pinfo->fd->abs_ts.nsecs - lastData->received_time.nsecs;
/* Looking for a frame sent 8 or 9 subframes previously.
TODO: have even seen retx 10 SFs later... */
gboolean found_match = FALSE;
gint SFs_ago;
/* Round difference to nearest millisecond */
gint total_gap = (seconds_between_packets*1000) +
((nseconds_between_packets+500000) / 1000000);
for (SFs_ago=8; (SFs_ago <= 9) && !found_match; SFs_ago++) {
/* Check 8 SFs ago */
lastData = &(ueData->subframe[(p_mac_lte_info->subframeNumber+(10-SFs_ago)) % 10]);
if (lastData->inUse) {
/* Compare time, sf, data to see if this looks like a retx */
if ((tvb_length_remaining(tvb, offset) == lastData->length) &&
(memcmp(lastData->data,
tvb_get_ptr(tvb, offset, lastData->length),
MIN(lastData->length, MAX_EXPECTED_PDU_LENGTH)) == 0)) {
/* Should be 8 ms apart - allow some leeway */
if ((total_gap >= 7) && (total_gap <= 9)) {
/* Resend detected!!! Store result */
result = se_alloc(sizeof(DLHARQResult));
result->previousFrameNum = lastData->framenum;
g_hash_table_insert(mac_lte_dl_harq_result_hash, GUINT_TO_POINTER(pinfo->fd->num), result);
/* Work out gap between frames */
gint seconds_between_packets = (gint)
(pinfo->fd->abs_ts.secs - lastData->received_time.secs);
gint nseconds_between_packets =
pinfo->fd->abs_ts.nsecs - lastData->received_time.nsecs;
/* Round difference to nearest millisecond */
gint total_gap = (seconds_between_packets*1000) +
((nseconds_between_packets+500000) / 1000000);
/* Should be equal to number of subframes - allow some leeway */
if ((total_gap >= (SFs_ago-1)) && (total_gap <= (SFs_ago+1))) {
found_match = TRUE;
/* Resend detected!!! Store result */
result = se_alloc(sizeof(DLHARQResult));
result->previousFrameNum = lastData->framenum;
g_hash_table_insert(mac_lte_dl_harq_result_hash, GUINT_TO_POINTER(pinfo->fd->num), result);
}
}
}
}
@ -2349,9 +2360,12 @@ static void dissect_ulsch_or_dlsch(tvbuff_t *tvb, packet_info *pinfo, proto_tree
ta_value = tvb_get_guint8(tvb, offset) & 0x3f;
ta_ti = proto_tree_add_item(tree, hf_mac_lte_control_timing_advance,
tvb, offset, 1, FALSE);
expert_add_info_format(pinfo, ta_ti, PI_SEQUENCE, PI_WARN,
"Timing Advance control element received (%u)",
ta_value);
if (ta_value > 0) {
expert_add_info_format(pinfo, ta_ti, PI_SEQUENCE,
(ta_value <= 31) ? PI_NOTE : PI_WARN,
"Timing Advance control element received (%u)",
ta_value);
}
offset++;
}
break;
@ -3183,6 +3197,12 @@ void proto_register_mac_lte(void)
"Subframe number associated with message", HFILL
}
},
{ &hf_mac_lte_context_grant_subframe_number,
{ "Grant Subframe",
"mac-lte.grant-subframe", FT_UINT16, BASE_DEC, 0, 0x0,
"Subframe grant for this PDU was received", HFILL
}
},
{ &hf_mac_lte_context_predefined_frame,
{ "Predefined frame",
"mac-lte.is-predefined-frame", FT_UINT8, BASE_DEC, VALS(predefined_frame_vals), 0x0,