From 9870c73366091e38a476b0b2ed176139fce3e2d9 Mon Sep 17 00:00:00 2001
From: Pedro Alvarez <pedro.alvarez@softwareradiosystems.com>
Date: Tue, 19 Nov 2019 18:12:01 +0000
Subject: [PATCH] Starting to add discardTimers to PDCP NR.

---
 lib/include/srslte/common/interfaces_common.h | 25 +++++++++++++++++--
 lib/src/upper/pdcp_entity_nr.cc               |  9 +++++--
 2 files changed, 30 insertions(+), 4 deletions(-)

diff --git a/lib/include/srslte/common/interfaces_common.h b/lib/include/srslte/common/interfaces_common.h
index 5a88563de..ad3d18050 100644
--- a/lib/include/srslte/common/interfaces_common.h
+++ b/lib/include/srslte/common/interfaces_common.h
@@ -76,7 +76,7 @@ const uint8_t PDCP_SN_LEN_18 = 18;
 
 typedef enum { PDCP_RB_IS_SRB, PDCP_RB_IS_DRB } pdcp_rb_type_t;
 
-// Take from PDCP-Config (TS 38.331 version 15.2.1)
+// Taken from PDCP-Config (TS 38.331 version 15.2.1)
 enum class pdcp_t_reordering_t {
   ms0    = 0,
   ms1    = 1,
@@ -116,6 +116,26 @@ enum class pdcp_t_reordering_t {
   ms3000 = 3000
 };
 
+// Taken from PDCP-Config (TS 38.331 version 15.2.1)
+enum class pdcp_discard_timer_t {
+  ms10 = 10,
+  ms20 = 20,
+  ms30 = 30,
+  ms40 = 40,
+  ms50 = 50,
+  ms60 = 60,
+  ms75 = 75,
+  ms100 = 100,
+  ms150 = 150,
+  ms200 = 200,
+  ms250 = 250,
+  ms300 = 300,
+  ms500 = 500,
+  ms750 = 750,
+  ms1500 = 1500,
+  infinity = 0
+};
+
 class pdcp_config_t
 {
 public:
@@ -142,7 +162,8 @@ public:
   uint8_t              sn_len        = PDCP_SN_LEN_12;
   uint8_t              hdr_len_bytes = 2;
 
-  pdcp_t_reordering_t t_reordering = pdcp_t_reordering_t::ms500;
+  pdcp_t_reordering_t  t_reordering  = pdcp_t_reordering_t::ms500;
+  pdcp_discard_timer_t discard_timer = pdcp_discard_timer_t::infinity;
 
   // TODO: Support the following configurations
   // bool do_rohc;
diff --git a/lib/src/upper/pdcp_entity_nr.cc b/lib/src/upper/pdcp_entity_nr.cc
index 247924b2f..3bc8fe060 100644
--- a/lib/src/upper/pdcp_entity_nr.cc
+++ b/lib/src/upper/pdcp_entity_nr.cc
@@ -73,7 +73,7 @@ void pdcp_entity_nr::reestablish()
 void pdcp_entity_nr::reset()
 {
   active = false;
-  if (log) {
+  if (log != nullptr) {
     log->debug("Reset %s\n", rrc->get_rb_name(lcid).c_str());
   }
 }
@@ -103,7 +103,12 @@ void pdcp_entity_nr::write_sdu(unique_byte_buffer_t sdu, bool blocking)
     tx_overflow = true;
   }
 
-  // Start discard timer TODO
+  // Start discard timer
+  if (cfg.discard_timer != pdcp_discard_timer_t::infinity) {
+    timer_handler::unique_timer discard_timer = timers->get_unique_timer();
+    reordering_timer.set(static_cast<uint32_t>(cfg.discard_timer), [](uint32_t tid) {});
+  }
+
   // Perform header compression TODO
 
   // Integrity protection