add RLC AM NR PDU packing and unpacking

lib/include/srslte/interfaces/rrc_interface_types.h

@@ -203,6 +203,7 @@ inline uint16_t to_number(const rlc_umd_sn_size_t& sn_size)
   return enum_to_number(options, (uint32_t)rlc_mode_t::nulltype, (uint32_t)sn_size);
 }
 
+///< RLC UM NR sequence number field
 enum class rlc_um_nr_sn_size_t { size6bits, size12bits, nulltype };
 inline std::string to_string(const rlc_um_nr_sn_size_t& sn_size)
 {
@@ -215,6 +216,19 @@ inline uint16_t to_number(const rlc_um_nr_sn_size_t& sn_size)
   return enum_to_number(options, (uint32_t)rlc_mode_t::nulltype, (uint32_t)sn_size);
 }
 
+///< RLC AM NR sequence number field
+enum class rlc_am_nr_sn_size_t { size12bits, size18bits, nulltype };
+inline std::string to_string(const rlc_am_nr_sn_size_t& sn_size)
+{
+  constexpr static const char* options[] = {"12 bits", "18 bits"};
+  return enum_to_text(options, (uint32_t)rlc_mode_t::nulltype, (uint32_t)sn_size);
+}
+inline uint16_t to_number(const rlc_am_nr_sn_size_t& sn_size)
+{
+  constexpr static uint16_t options[] = {12, 18};
+  return enum_to_number(options, (uint32_t)rlc_mode_t::nulltype, (uint32_t)sn_size);
+}
+
 struct rlc_am_config_t {
   /****************************************************************************
    * Configurable parameters

lib/include/srslte/upper/rlc_am_base.h

@@ -0,0 +1,42 @@
+/*
+ * Copyright 2013-2019 Software Radio Systems Limited
+ *
+ * This file is part of srsLTE.
+ *
+ * srsLTE is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * srsLTE is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * A copy of the GNU Affero General Public License can be found in
+ * the LICENSE file in the top-level directory of this distribution
+ * and at http://www.gnu.org/licenses/.
+ *
+ */
+
+#ifndef SRSLTE_RLC_AM_BASE_H
+#define SRSLTE_RLC_AM_BASE_H
+
+#include "srslte/common/buffer_pool.h"
+#include "srslte/common/common.h"
+#include "srslte/common/log.h"
+#include "srslte/interfaces/ue_interfaces.h"
+#include "srslte/upper/rlc_common.h"
+#include "srslte/upper/rlc_tx_queue.h"
+#include <map>
+#include <mutex>
+#include <pthread.h>
+#include <queue>
+
+namespace srslte {
+
+///< Add rlc_am_base here
+
+} // namespace srslte
+
+#endif // SRSLTE_RLC_AM_BASE_H

lib/include/srslte/upper/rlc_am_nr.h

@@ -0,0 +1,64 @@
+/*
+ * Copyright 2013-2019 Software Radio Systems Limited
+ *
+ * This file is part of srsLTE.
+ *
+ * srsLTE is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * srsLTE is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * A copy of the GNU Affero General Public License can be found in
+ * the LICENSE file in the top-level directory of this distribution
+ * and at http://www.gnu.org/licenses/.
+ *
+ */
+
+#ifndef SRSLTE_RLC_AM_NR_H
+#define SRSLTE_RLC_AM_NR_H
+
+#include "srslte/common/buffer_pool.h"
+#include "srslte/common/common.h"
+#include "srslte/common/log.h"
+#include "srslte/interfaces/ue_interfaces.h"
+#include "srslte/upper/rlc_am_base.h"
+#include "srslte/upper/rlc_tx_queue.h"
+#include <map>
+#include <mutex>
+#include <pthread.h>
+#include <queue>
+
+namespace srslte {
+
+typedef struct {
+  rlc_am_nr_pdu_header_t header;
+  unique_byte_buffer_t   buf;
+} rlc_amd_pdu_nr_t;
+
+///< add class here
+
+/****************************************************************************
+ * Header pack/unpack helper functions for NR
+ * Ref: 3GPP TS 38.322 v15.3.0 Section 6.2.2.3
+ ***************************************************************************/
+uint32_t rlc_am_nr_read_data_pdu_header(const byte_buffer_t*      pdu,
+                                        const rlc_am_nr_sn_size_t sn_size,
+                                        rlc_am_nr_pdu_header_t*   header);
+
+uint32_t rlc_am_nr_read_data_pdu_header(const uint8_t*            payload,
+                                        const uint32_t            nof_bytes,
+                                        const rlc_am_nr_sn_size_t sn_size,
+                                        rlc_am_nr_pdu_header_t*   header);
+
+uint32_t rlc_am_nr_write_data_pdu_header(const rlc_am_nr_pdu_header_t& header, byte_buffer_t* pdu);
+
+uint32_t rlc_am_nr_packed_length(const rlc_am_nr_pdu_header_t& header);
+
+} // namespace srslte
+
+#endif // SRSLTE_RLC_AM_NR_H

lib/include/srslte/upper/rlc_common.h

@@ -77,11 +77,11 @@ static inline uint8_t operator&(rlc_nr_si_field_t lhs, int rhs)
                               static_cast<std::underlying_type<rlc_nr_si_field_t>::type>(rhs));
 }
 
-typedef enum{
+typedef enum {
   RLC_DC_FIELD_CONTROL_PDU = 0,
   RLC_DC_FIELD_DATA_PDU,
   RLC_DC_FIELD_N_ITEMS,
-}rlc_dc_field_t;
+} rlc_dc_field_t;
 static const char rlc_dc_field_text[RLC_DC_FIELD_N_ITEMS][20] = {"Control PDU",
                                                                  "Data PDU"};
 
@@ -169,6 +169,18 @@ struct rlc_status_pdu_t{
   rlc_status_pdu_t(){N_nack=0; ack_sn=0;}
 };
 
+/** RLC AM NR structs */
+
+///< AM NR PDU header
+typedef struct {
+  rlc_dc_field_t      dc;      ///< Data/Control (D/C) field
+  uint8_t             p;       ///< Polling bit
+  rlc_nr_si_field_t   si;      ///< Segmentation info
+  rlc_am_nr_sn_size_t sn_size; ///< Sequence number size (12 or 18 bits)
+  uint32_t            sn;      ///< Sequence number
+  uint16_t            so;      ///< Sequence offset
+} rlc_am_nr_pdu_header_t;
+
 /****************************************************************************
  * RLC Common interface
  * Common interface for all RLC entities

lib/src/upper/CMakeLists.txt

@@ -28,7 +28,8 @@ set(SOURCES gtpu.cc
             rlc_um_base.cc
             rlc_um_lte.cc
             rlc_um_nr.cc
-            rlc_am_lte.cc)
+            rlc_am_lte.cc
+            rlc_am_nr.cc)
 add_library(srslte_upper STATIC ${SOURCES})
 target_link_libraries(srslte_upper srslte_common srslte_asn1)
 install(TARGETS srslte_upper DESTINATION ${LIBRARY_DIR})

lib/src/upper/rlc_am_nr.cc

@@ -0,0 +1,147 @@
+/*
+ * Copyright 2013-2019 Software Radio Systems Limited
+ *
+ * This file is part of srsLTE.
+ *
+ * srsLTE is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * srsLTE is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * A copy of the GNU Affero General Public License can be found in
+ * the LICENSE file in the top-level directory of this distribution
+ * and at http://www.gnu.org/licenses/.
+ *
+ */
+
+#include "srslte/upper/rlc_am_nr.h"
+#include <sstream>
+
+namespace srslte {
+
+/****************************************************************************
+ * Header pack/unpack helper functions
+ * Ref: 3GPP TS 38.322 v15.3.0 Section 6.2.2.4
+ ***************************************************************************/
+
+uint32_t rlc_am_nr_read_data_pdu_header(const byte_buffer_t*      pdu,
+                                        const rlc_am_nr_sn_size_t sn_size,
+                                        rlc_am_nr_pdu_header_t*   header)
+{
+  return rlc_am_nr_read_data_pdu_header(pdu->msg, pdu->N_bytes, sn_size, header);
+}
+
+uint32_t rlc_am_nr_read_data_pdu_header(const uint8_t*            payload,
+                                        const uint32_t            nof_bytes,
+                                        const rlc_am_nr_sn_size_t sn_size,
+                                        rlc_am_nr_pdu_header_t*   header)
+{
+  uint8_t* ptr = const_cast<uint8_t*>(payload);
+
+  header->sn_size = sn_size;
+
+  // Fixed part
+  header->dc = (rlc_dc_field_t)((*ptr >> 7) & 0x01);    // 1 bit D/C field
+  header->p  = (*ptr >> 6) & 0x01;                      // 1 bit P flag
+  header->si = (rlc_nr_si_field_t)((*ptr >> 4) & 0x03); // 2 bits SI
+
+  if (sn_size == rlc_am_nr_sn_size_t::size12bits) {
+    header->sn = (*ptr & 0x0F) << 8; // first 4 bits SN
+    ptr++;
+
+    header->sn |= (*ptr & 0xFF); // last 8 bits SN
+    ptr++;
+  } else if (sn_size == rlc_am_nr_sn_size_t::size18bits) {
+    // sanity check
+    if (header->sn > 3) {
+      fprintf(stderr, "Malformed PDU, reserved bits are set.\n");
+      return 0;
+    }
+    header->sn |= (*ptr & 0xFF); // bit 2-10 of SN
+    ptr++;
+    header->sn |= (*ptr & 0xFF); // last 8 bits SN
+    ptr++;
+  } else {
+    fprintf(stderr, "Unsupported SN length\n");
+    return 0;
+  }
+
+  // Read optional part
+  if (header->si == rlc_nr_si_field_t::last_segment ||
+      header->si == rlc_nr_si_field_t::neither_first_nor_last_segment) {
+    // read SO
+    header->so = (*ptr & 0xFF) << 8;
+    ptr++;
+    header->so |= (*ptr & 0xFF);
+    ptr++;
+  }
+
+  // return consumed bytes
+  return (ptr - payload);
+}
+
+uint32_t rlc_am_nr_packed_length(const rlc_am_nr_pdu_header_t& header)
+{
+  uint32_t len = 0;
+  if (header.si == rlc_nr_si_field_t::full_sdu || header.si == rlc_nr_si_field_t::first_segment) {
+    len = 2;
+    if (header.sn_size == rlc_am_nr_sn_size_t::size18bits) {
+      len++;
+    }
+  } else {
+    // PDU contains SO
+    len = 4;
+    if (header.sn_size == rlc_am_nr_sn_size_t::size18bits) {
+      len++;
+    }
+  }
+  return len;
+}
+
+uint32_t rlc_am_nr_write_data_pdu_header(const rlc_am_nr_pdu_header_t& header, byte_buffer_t* pdu)
+{
+  // Make room for the header
+  uint32_t len = rlc_am_nr_packed_length(header);
+  pdu->msg -= len;
+  uint8_t* ptr = pdu->msg;
+
+  // fixed header part
+  *ptr = (header.dc & 0x01) << 7;  ///< 1 bit D/C field
+  *ptr |= (header.p & 0x01) << 6;  ///< 1 bit P flag
+  *ptr |= (header.si & 0x03) << 4; ///< 2 bits SI
+
+  if (header.sn_size == rlc_am_nr_sn_size_t::size12bits) {
+    // write first 4 bit of SN
+    *ptr |= (header.sn >> 8) & 0x0f; // 4 bit SN
+    ptr++;
+    *ptr = header.sn & 0xff; // remaining 8 bit of SN
+    ptr++;
+  } else {
+    // 18bit SN
+    *ptr |= (header.sn & 0x3); // 2 bit SN
+    ptr++;
+    *ptr = (header.sn) >> 8; // bit 3 - 10 of SN
+    ptr++;
+    *ptr = (header.sn & 0xff); // remaining 8 bit of SN
+    ptr++;
+  }
+
+  if (header.so) {
+    // write SO
+    *ptr = header.so >> 8; // first part of SO
+    ptr++;
+    *ptr = (header.so & 0xff); // second part of SO
+    ptr++;
+  }
+
+  pdu->N_bytes += ptr - pdu->msg;
+
+  return len;
+}
+
+} // namespace srslte