From 91fd4ddf7e22951c0deb8b4406d2aa021019336d Mon Sep 17 00:00:00 2001
From: Robert Schmidt <robert.schmidt@eurecom.fr>
Date: Wed, 9 Dec 2020 17:31:02 +0100
Subject: [PATCH] rewrite nr_acknack_scheduling()
---
.../LAYER2/NR_MAC_gNB/gNB_scheduler_uci.c | 170 +++++++++++++-----
1 file changed, 122 insertions(+), 48 deletions(-)
diff --git a/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_uci.c b/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_uci.c
index 1e09f3777b..f1200f19de 100644
--- a/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_uci.c
+++ b/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_uci.c
@@ -430,79 +430,153 @@ bool nr_acknack_scheduling(int mod_id,
frame_t frame,
sub_frame_t slot)
{
+ const NR_ServingCellConfigCommon_t *scc = RC.nrmac[mod_id]->common_channels->ServingCellConfigCommon;
+ const int n_slots_frame = nr_slots_per_frame[*scc->ssbSubcarrierSpacing];
+ const NR_TDD_UL_DL_Pattern_t *tdd_pattern = &scc->tdd_UL_DL_ConfigurationCommon->pattern1;
+ const int nr_ulmix_slots = tdd_pattern->nrofUplinkSlots + (tdd_pattern->nrofUplinkSymbols != 0);
+ const int first_ul_slot_tdd = tdd_pattern->nrofDownlinkSlots;
+ const int CC_id = 0;
+
+ AssertFatal(slot < first_ul_slot_tdd + (tdd_pattern->nrofUplinkSymbols != 0),
+ "cannot handle multiple TDD periods (yet): slot %d first_ul_slot_tdd %d nrofUplinkSlots %ld\n",
+ slot,
+ first_ul_slot_tdd,
+ tdd_pattern->nrofUplinkSlots);
+
/* FIXME: for the moment, we consider that
- * * only pucch_sched[0] holds HARQ
- * * a UE is not scheduled in more than two slots, and their ACKs come in the same slot!
+ * * only pucch_sched[0] holds HARQ (and SR)
* * we do not multiplex with CSI
- * * we do not mux two UEs in the same PUCCH slot (on the two symbols)
* * we only use the first TDD period (5/10ms) */
NR_UE_sched_ctrl_t *sched_ctrl = &RC.nrmac[mod_id]->UE_info.UE_sched_ctrl[UE_id];
- NR_sched_pucch_t *curr_pucch = &sched_ctrl->sched_pucch[0];
- AssertFatal(curr_pucch->csi_bits == 0,
+ NR_sched_pucch_t *pucch = &sched_ctrl->sched_pucch[0];
+ AssertFatal(pucch->csi_bits == 0,
"%s(): csi_bits %d in sched_pucch[0]\n",
__func__,
- curr_pucch->csi_bits);
+ pucch->csi_bits);
const int max_acknacks = 2;
- AssertFatal(curr_pucch->dai_c <= max_acknacks,
- "%s() called but already %d dai_c in sched_pucch[0]\n",
- __func__,
- curr_pucch->dai_c);
-
- const NR_ServingCellConfigCommon_t *scc = RC.nrmac[mod_id]->common_channels->ServingCellConfigCommon;
- const NR_TDD_UL_DL_Pattern_t *tdd_pattern = &scc->tdd_UL_DL_ConfigurationCommon->pattern1;
- //const int nr_ulmix_slots = tdd_pattern->nrofUplinkSlots + (tdd_pattern->nrofUplinkSymbols != 0);
- const int first_ul_slot_tdd = tdd_pattern->nrofDownlinkSlots;
- const int CC_id = 0;
+ AssertFatal(pucch->dai_c + pucch->sr_flag <= max_acknacks,
+ "illegal number of bits in PUCCH of UE %d\n",
+ UE_id);
+ /* if the currently allocated PUCCH of this UE is full, allocate it */
+ if (pucch->sr_flag + pucch->dai_c == max_acknacks) {
+ /* advance the UL slot information in PUCCH by one so we won't schedule in
+ * the same slot again */
+ const int f = pucch->frame;
+ const int s = pucch->ul_slot;
+ nr_fill_nfapi_pucch(mod_id, frame, slot, pucch, UE_id);
+ memset(pucch, 0, sizeof(*pucch));
+ pucch->frame = s == n_slots_frame - 1 ? (f + 1) % 1024 : f;
+ pucch->ul_slot = (s + 1) % n_slots_frame;
+ }
// this is hardcoded for now as ue specific
NR_SearchSpace__searchSpaceType_PR ss_type = NR_SearchSpace__searchSpaceType_PR_ue_Specific;
uint8_t pdsch_to_harq_feedback[8];
get_pdsch_to_harq_feedback(mod_id, UE_id, ss_type, pdsch_to_harq_feedback);
+ /* there is a scheduled SR or HARQ. Check whether we can use it for this
+ * ACKNACK */
+ if (pucch->sr_flag + pucch->dai_c > 0) {
+ /* this UE already has a PUCCH occasion */
+ DevAssert(pucch->frame == frame);
+
+ // Find the right timing_indicator value.
+ int i = 0;
+ while (i < 8) {
+ if (pdsch_to_harq_feedback[i] == pucch->ul_slot - slot)
+ break;
+ ++i;
+ }
+ if (i >= 8) {
+ // we cannot reach this timing anymore, allocate and try again
+ const int f = pucch->frame;
+ const int s = pucch->ul_slot;
+ const int n_slots_frame = nr_slots_per_frame[*scc->ssbSubcarrierSpacing];
+ nr_fill_nfapi_pucch(mod_id, frame, slot, pucch, UE_id);
+ memset(pucch, 0, sizeof(*pucch));
+ pucch->frame = s == n_slots_frame - 1 ? (f + 1) % 1024 : f;
+ pucch->ul_slot = (s + 1) % n_slots_frame;
+ return nr_acknack_scheduling(mod_id, UE_id, frame, slot);
+ }
+
+ pucch->timing_indicator = i;
+ pucch->dai_c++;
+ // retain old resource indicator, and we are good
+ return true;
+ }
+
+ /* we need to find a new PUCCH occasion */
+
NR_PUCCH_Config_t *pucch_Config = sched_ctrl->active_ubwp->bwp_Dedicated->pucch_Config->choice.setup;
DevAssert(pucch_Config->resourceToAddModList->list.count > 0);
+ DevAssert(pucch_Config->resourceSetToAddModList->list.count > 0);
+ const int n_res = pucch_Config->resourceSetToAddModList->list.array[0]->resourceList.list.count;
+ int *pucch_index_used = RC.nrmac[mod_id]->pucch_index_used[sched_ctrl->active_ubwp->bwp_Id];
- curr_pucch->frame = frame;
- curr_pucch->dai_c++;
+ /* if time information is outdated (e.g., last PUCCH occasion in last frame),
+ * set to first possible UL occasion in this frame */
+ if (frame != pucch->frame || pucch->ul_slot < first_ul_slot_tdd) {
+ DevAssert(pucch->sr_flag + pucch->dai_c == 0);
+ pucch->frame = frame;
+ pucch->ul_slot = first_ul_slot_tdd;
+ }
- int *pucch_index_used = RC.nrmac[mod_id]->pucch_index_used[sched_ctrl->active_ubwp->bwp_Id];
- if (curr_pucch->dai_c == 1) {
- /* FIXME for first allocation: find free resource, here assume first PUCCH
- * resource and first_ul_slot_tdd */
- const int pucch_res = 0;
- curr_pucch->resource_indicator = pucch_res;
- curr_pucch->ul_slot = first_ul_slot_tdd;
- DevAssert(pucch_index_used[first_ul_slot_tdd] == 0);
- pucch_index_used[first_ul_slot_tdd] += 1;
-
- /* verify that at that slot and symbol, resources are free.
- * Note: this does not handle potential mux of PUCCH in the same symbol! */
- const NR_PUCCH_Resource_t *resource =
- pucch_Config->resourceToAddModList->list.array[pucch_res];
- DevAssert(resource->format.present == NR_PUCCH_Resource__format_PR_format0);
- uint16_t *vrb_map_UL =
- &RC.nrmac[mod_id]->common_channels[CC_id].vrb_map_UL[first_ul_slot_tdd * 275];
- const uint16_t symb = 1 << resource->format.choice.format0->startingSymbolIndex;
- AssertFatal((vrb_map_UL[resource->startingPRB] & symb) == 0,
- "symbol %x is not free for PUCCH alloc in vrb_map_UL at RB %ld and slot %d\n",
- symb, resource->startingPRB, first_ul_slot_tdd);
- vrb_map_UL[resource->startingPRB] |= symb;
+ // increase to first slot in which PUCCH resources are available
+ while (pucch_index_used[pucch->ul_slot] >= n_res) {
+ pucch->ul_slot++;
+ /* if there is no free resource anymore, abort search */
+ if (pucch->ul_slot >= first_ul_slot_tdd + nr_ulmix_slots) {
+ LOG_E(MAC,
+ "%4d.%2d no free PUCCH resources anymore while searching for UE %d\n",
+ frame,
+ slot,
+ UE_id);
+ return false;
+ }
}
- /* Find the right timing_indicator value. FIXME: if previously ul_slot is not
- * possible (anymore), we need to allocate previous HARQ feedback (since we
- * cannot "reach" it anymore) and search a new one! */
+ // advance ul_slot if it is not reachable by UE
+ pucch->ul_slot = max(pucch->ul_slot, slot + pdsch_to_harq_feedback[0]);
+
+ // Find the right timing_indicator value.
int i = 0;
while (i < 8) {
- if (pdsch_to_harq_feedback[i] == curr_pucch->ul_slot - slot)
+ if (pdsch_to_harq_feedback[i] == pucch->ul_slot - slot)
break;
++i;
}
- AssertFatal(i < 8,
- "could not find pdsch_to_harq_feedback: slot %d, ack slot %d\n",
- slot, first_ul_slot_tdd);
- curr_pucch->timing_indicator = i; // index in the list of timing indicators
+ if (i >= 8) {
+ LOG_W(MAC,
+ "%4d.%2d could not find pdsch_to_harq_feedback for UE %d: earliest "
+ "ack slot %d\n",
+ frame,
+ slot,
+ UE_id,
+ pucch->ul_slot);
+ return false;
+ }
+ pucch->timing_indicator = i; // index in the list of timing indicators
+
+ pucch->dai_c++;
+ const int pucch_res = pucch_index_used[pucch->ul_slot];
+ pucch->resource_indicator = pucch_res;
+ pucch_index_used[first_ul_slot_tdd] += 1;
+
+ /* verify that at that slot and symbol, resources are free. We only do this
+ * for initialCyclicShift 0 (we assume it always has that one), so other
+ * initialCyclicShifts can overlap with ICS 0!*/
+ const NR_PUCCH_Resource_t *resource =
+ pucch_Config->resourceToAddModList->list.array[pucch_res];
+ DevAssert(resource->format.present == NR_PUCCH_Resource__format_PR_format0);
+ if (resource->format.choice.format0->initialCyclicShift == 0) {
+ uint16_t *vrb_map_UL = &RC.nrmac[mod_id]->common_channels[CC_id].vrb_map_UL[pucch->ul_slot * MAX_BWP_SIZE];
+ const uint16_t symb = 1 << resource->format.choice.format0->startingSymbolIndex;
+ AssertFatal((vrb_map_UL[resource->startingPRB] & symb) == 0,
+ "symbol %x is not free for PUCCH alloc in vrb_map_UL at RB %ld and slot %d\n",
+ symb, resource->startingPRB, first_ul_slot_tdd);
+ vrb_map_UL[resource->startingPRB] |= symb;
+ }
return true;
}
--
2.26.2