L1 DLSCH: don't preallocate memory, improve log

The L1 receives a pointer to the L1 payload to use for PDSCH generation.
This would overwrite an existing pre-allocated pointer. Remove this
preallocation. Instead, allocate it in the simulator (the only place
that actively uses this buffer allocation; in nr-softmodem, it's lost by
assigning a pointer). Allocate with an extra byte, because the payload
(in bits) might not be a multiple of 8 bits/1 byte, so the CRC is in the
last 3 bytes.

Also, improve the log with frame/slot information if the PDSCH payload
pointer is NULL.

openair1/PHY/NR_TRANSPORT/nr_dlsch.c

@@ -93,7 +93,7 @@ void nr_generate_pdsch(processingData_L1tx_t *msgTx, int frame, int slot)
     harq->unav_res = ptrsSymbPerSlot * n_ptrs;
 
     /// CRC, coding, interleaving and rate matching
-    AssertFatal(harq->pdu!=NULL,"harq->pdu is null\n");
+    AssertFatal(harq->pdu != NULL, "%4d.%2d no HARQ PDU for PDSCH generation\n", msgTx->frame, msgTx->slot);
 
     /* output and its parts for each dlsch should be aligned on 64 bytes
      * => size_output is a sum of parts sizes rounded up to a multiple of 64

openair1/PHY/NR_TRANSPORT/nr_dlsch.h

@@ -56,8 +56,6 @@ int nr_dlsch_encoding(PHY_VARS_gNB *gNB,
                       time_stats_t *dlsch_interleaving_stats,
                       time_stats_t *dlsch_segmentation_stats);
 
-void nr_emulate_dlsch_payload(uint8_t* payload, uint16_t size);
-
 void dump_pdsch_stats(FILE *fd,PHY_VARS_gNB *gNB);
 
 #endif

openair1/PHY/NR_TRANSPORT/nr_dlsch_coding.c

@@ -66,7 +66,6 @@ void free_gNB_dlsch(NR_gNB_DLSCH_t *dlsch, uint16_t N_RB, const NR_DL_FRAME_PARM
     harq->c[r] = NULL;
   }
   free(harq->c);
-  free(harq->pdu);
 }
 
 NR_gNB_DLSCH_t new_gNB_dlsch(NR_DL_FRAME_PARMS *frame_parms, uint16_t N_RB)
@@ -87,10 +86,6 @@ NR_gNB_DLSCH_t new_gNB_dlsch(NR_DL_FRAME_PARMS *frame_parms, uint16_t N_RB)
   bzero(harq, sizeof(NR_DL_gNB_HARQ_t));
   harq->b = malloc16(dlsch_bytes);
   AssertFatal(harq->b, "cannot allocate memory for harq->b\n");
-  harq->pdu = malloc16(dlsch_bytes);
-  AssertFatal(harq->pdu, "cannot allocate memory for harq->pdu\n");
-  bzero(harq->pdu, dlsch_bytes);
-  nr_emulate_dlsch_payload(harq->pdu, (dlsch_bytes) >> 3);
   bzero(harq->b, dlsch_bytes);
 
   harq->c = (uint8_t **)malloc16(a_segments*sizeof(uint8_t *));

openair1/PHY/NR_TRANSPORT/nr_dlsch_tools.c

@@ -36,14 +36,6 @@
 
 extern void set_taus_seed(unsigned int seed_type);
 
-
-/// Payload emulation
-void nr_emulate_dlsch_payload(uint8_t* pdu, uint16_t size) {
-  set_taus_seed(0);
-  for (int i=0; i<size; i++)
-    *(pdu+i) = (uint8_t)rand();
-}
-
 void nr_fill_dlsch_dl_tti_req(processingData_L1tx_t *msgTx, nfapi_nr_dl_tti_pdsch_pdu *pdsch_pdu)
 {
   NR_gNB_DLSCH_t *dlsch = &msgTx->dlsch[msgTx->num_pdsch_slot][0];

openair1/SIMULATION/NR_PHY/dlschsim.c

@@ -497,7 +497,8 @@ int main(int argc, char **argv)
   dlsch0_ue->dlsch_config.tbslbrm = Tbslbrm;
 	printf("harq process ue mcs = %d Qm = %d, symb %d\n", dlsch0_ue->dlsch_config.mcs, dlsch0_ue->dlsch_config.qamModOrder, nb_symb_sch);
 
-	unsigned char *test_input=dlsch->harq_process.pdu;
+  uint8_t test_input[TBS / 8 + 4]; // + 3 for CRC + 1 additional byte, see nr_dlsch_encoding()
+  dlsch->harq_process.pdu = test_input;
 	//unsigned char test_input[TBS / 8]  __attribute__ ((aligned(16)));
 	for (i = 0; i < TBS / 8; i++)
 		test_input[i] = (unsigned char) rand();