PDSCH decoder multi has been modified for future parallel decoding of codewords.

lib/include/srslte/phy/phch/sch.h

@@ -108,11 +108,12 @@ SRSLTE_API int srslte_dlsch_decode(srslte_sch_t *q,
                                    int16_t *e_bits, 
                                    uint8_t *data);
 
-SRSLTE_API int srslte_dlsch_decode_multi(srslte_sch_t *q,
+SRSLTE_API int srslte_dlsch_decode2(srslte_sch_t *q,
                                    srslte_pdsch_cfg_t *cfg,
-                                   srslte_softbuffer_rx_t softbuffers[SRSLTE_MAX_CODEWORDS],
-                                   int16_t *e_bits[SRSLTE_MAX_CODEWORDS],
-                                   uint8_t *data[SRSLTE_MAX_CODEWORDS]);
+                                   srslte_softbuffer_rx_t *softbuffer,
+                                   int16_t *e_bits,
+                                   uint8_t *data,
+                                   int codeword_idx);
 
 SRSLTE_API int srslte_ulsch_encode(srslte_sch_t *q, 
                                    srslte_pusch_cfg_t *cfg,

lib/src/phy/phch/pdsch.c

@@ -33,6 +33,8 @@
 #include <assert.h>
 #include <math.h>
 #include <srslte/phy/phch/pdsch.h>
+#include <srslte/phy/phch/ra.h>
+#include <srslte/phy/phch/pdsch_cfg.h>
 
 #include "prb_dl.h"
 #include "srslte/phy/phch/pdsch.h"
@@ -488,6 +490,7 @@ int srslte_pdsch_decode_multi(srslte_pdsch_t *q,
   /* Set pointers for layermapping & precoding */
   uint32_t i, n;
   cf_t *x[SRSLTE_MAX_LAYERS];
+  int ret = 0;
 
   if (q            != NULL &&
       sf_symbols   != NULL &&
@@ -564,26 +567,14 @@ int srslte_pdsch_decode_multi(srslte_pdsch_t *q,
     * The MAX-log-MAP algorithm used in turbo decoding is unsensitive to SNR estimation, 
     * thus we don't need tot set it in the LLRs normalization
     */
-    if (cfg->nbits.nof_re) {
+    if (cfg->nbits.nof_bits) {
+      INFO("Decoding CW 0 (%d bits)\n", cfg->nbits.nof_bits);
       srslte_demod_soft_demodulate_s(cfg->grant.mcs.mod, q->d, q->e, cfg->nbits.nof_re);
-    }
-
-    if (cfg->nbits2.nof_re) {
-      srslte_demod_soft_demodulate_s(cfg->grant.mcs2.mod, q->d2, q->e2, cfg->nbits2.nof_re);
-    }
 
-    /* descramble */
-    if (q->users[rnti] && q->users[rnti]->sequence_generated) {
-      if (cfg->nbits.nof_bits) {
+      if (q->users[rnti] && q->users[rnti]->sequence_generated) {
         srslte_scrambling_s_offset(&q->users[rnti]->seq[cfg->sf_idx], q->e, 0, cfg->nbits.nof_bits);
-      }
-
-      if (cfg->nbits2.nof_bits) {
-        srslte_scrambling_s_offset(&q->users[rnti]->seq2[cfg->sf_idx], q->e2, 0, cfg->nbits2.nof_bits);
-      }
-    } else {
-      srslte_sequence_t seq;
-      if (cfg->nbits.nof_bits) {
+      } else {
+        srslte_sequence_t seq;
         if (srslte_sequence_pdsch(&seq, rnti, 0, 2 * cfg->sf_idx, q->cell.id, cfg->nbits.nof_bits)) {
           return SRSLTE_ERROR;
         }
@@ -591,22 +582,34 @@ int srslte_pdsch_decode_multi(srslte_pdsch_t *q,
         srslte_sequence_free(&seq);
       }
 
-      if (cfg->nbits2.nof_bits) {
+      ret |= srslte_dlsch_decode2(&q->dl_sch, cfg, &softbuffers[0], q->e, data[0], 0);
+    }
+
+    if (cfg->nbits2.nof_bits) {
+      INFO("Decoding CW 1 (%d bits)\n", cfg->nbits2.nof_bits);
+      srslte_demod_soft_demodulate_s(cfg->grant.mcs2.mod, q->d2, q->e2, cfg->nbits2.nof_re);
+
+      if (q->users[rnti] && q->users[rnti]->sequence_generated) {
+        srslte_scrambling_s_offset(&q->users[rnti]->seq2[cfg->sf_idx], q->e2, 0, cfg->nbits2.nof_bits);
+      } else {
+        srslte_sequence_t seq;
         if (srslte_sequence_pdsch(&seq, rnti, 1, 2 * cfg->sf_idx, q->cell.id, cfg->nbits2.nof_bits)) {
           return SRSLTE_ERROR;
         }
         srslte_scrambling_s_offset(&seq, q->e2, 0, cfg->nbits2.nof_bits);
         srslte_sequence_free(&seq);
       }
+
+      ret |= srslte_dlsch_decode2(&q->dl_sch, cfg, &softbuffers[1], q->e2, data[1], 1);
     }
 
+
     if (SRSLTE_VERBOSE_ISDEBUG()) {
       DEBUG("SAVED FILE llr.dat: LLR estimates after demodulation and descrambling\n",0);
       srslte_vec_save_file("llr.dat", q->e, cfg->nbits.nof_bits*sizeof(int16_t));
     }
 
-    return srslte_dlsch_decode_multi(&q->dl_sch, cfg, softbuffers, (int16_t *[SRSLTE_MAX_CODEWORDS]) {q->e, q->e2},
-                                     data);
+    return ret;
     
   } else {
     return SRSLTE_ERROR_INVALID_INPUTS;

lib/src/phy/phch/sch.c

@@ -524,29 +524,28 @@ int srslte_dlsch_decode(srslte_sch_t *q, srslte_pdsch_cfg_t *cfg, srslte_softbuf
 }
 
 
-int srslte_dlsch_decode_multi(srslte_sch_t *q, srslte_pdsch_cfg_t *cfg, srslte_softbuffer_rx_t softbuffers[SRSLTE_MAX_CODEWORDS],
-                        int16_t *e_bits[SRSLTE_MAX_CODEWORDS], uint8_t *data[SRSLTE_MAX_CODEWORDS])
+int srslte_dlsch_decode2(srslte_sch_t *q, srslte_pdsch_cfg_t *cfg, srslte_softbuffer_rx_t *softbuffer,
+                        int16_t *e_bits, uint8_t *data, int codeword_idx)
 {
-  int ret  = SRSLTE_SUCCESS;
   uint32_t Nl = 1;
 
   if (cfg->nof_layers != cfg->grant.nof_tb) {
     Nl = 2;
   }
 
-  if (cfg->nbits.nof_bits) {
-    ret |= decode_tb(q, &softbuffers[0], &cfg->cb_segm,
+  if (codeword_idx == 0) {
+    return decode_tb(q, softbuffer, &cfg->cb_segm,
                      cfg->grant.Qm*Nl, cfg->rv, cfg->nbits.nof_bits,
-                     e_bits[0], data[0]);
+                     e_bits, data);
   }
 
-  if (cfg->nbits2.nof_bits) {
-    ret |= decode_tb(q, &softbuffers[1], &cfg->cb_segm2,
+  if (codeword_idx == 1) {
+    return decode_tb(q, softbuffer, &cfg->cb_segm2,
                      cfg->grant.Qm2*Nl, cfg->rv2, cfg->nbits2.nof_bits,
-                     e_bits[1], data[1]);
+                     e_bits, data);
   }
 
-  return ret;
+  return SRSLTE_ERROR;
 }
 
 /**