cts: update apply_ndr command. Now we have 4 options: none, root_only, half, full

Signed-off-by: Jonas Gava <[email protected]>

Author: jfgava

src/cts/src/CtsOptions.cpp

@@ -5,6 +5,31 @@
 
 namespace cts {
 
+void CtsOptions::setApplyNDR(const std::string& strategy)
+{
+  std::string lower_strategy = strategy;
+  std::transform(lower_strategy.begin(),
+                 lower_strategy.end(),
+                 lower_strategy.begin(),
+                 ::tolower);
+
+  if (lower_strategy == "none") {
+    ndrStrategy_ = NdrStrategy::NONE;
+  } else if (lower_strategy == "root_only") {
+    ndrStrategy_ = NdrStrategy::ROOT_ONLY;
+  } else if (lower_strategy == "half") {
+    ndrStrategy_ = NdrStrategy::HALF;
+  } else if (lower_strategy == "full") {
+    ndrStrategy_ = NdrStrategy::FULL;
+  } else {
+    logger_->warn(utl::CTS,
+                  33,
+                  "Invalid NDR strategy: {}. Defaulting to root_only.",
+                  strategy);
+    ndrStrategy_ = NdrStrategy::ROOT_ONLY;
+  }
+}
+
 CtsOptions::MasterType CtsOptions::getType(odb::dbInst* inst) const
 {
   if (inst->getName().substr(0, dummyload_prefix_.size())

src/cts/src/CtsOptions.h

@@ -27,6 +27,14 @@ namespace cts {
 class CtsOptions : public odb::dbBlockCallBackObj
 {
  public:
+  enum class NdrStrategy
+  {
+    NONE,
+    ROOT_ONLY,
+    HALF,
+    FULL
+  };
+
   enum class MasterType
   {
     DUMMY,
@@ -222,8 +230,6 @@ class CtsOptions : public odb::dbBlockCallBackObj
   stt::SteinerTreeBuilder* getSttBuilder() const { return sttBuilder_; }
   void setObstructionAware(bool obs) { obsAware_ = obs; }
   bool getObstructionAware() const { return obsAware_; }
-  void setApplyNDR(bool ndr) { applyNDR_ = ndr; }
-  bool applyNDR() const { return applyNDR_; }
   void enableInsertionDelay(bool insDelay) { insertionDelay_ = insDelay; }
   bool insertionDelayEnabled() const { return insertionDelay_; }
   void setBufferListInferred(bool inferred) { bufferListInferred_ = inferred; }
@@ -264,6 +270,10 @@ class CtsOptions : public odb::dbBlockCallBackObj
   void setRepairClockNets(bool value) { repairClockNets_ = value; }
   bool getRepairClockNets() { return repairClockNets_; }
 
+  // NDR strategies
+  void setApplyNDR(const std::string& strategy);
+  NdrStrategy getApplyNdr() const { return ndrStrategy_; }
+
  private:
   std::string clockNets_;
   std::string rootBuffer_;
@@ -315,7 +325,6 @@ class CtsOptions : public odb::dbBlockCallBackObj
   utl::Logger* logger_ = nullptr;
   stt::SteinerTreeBuilder* sttBuilder_ = nullptr;
   bool obsAware_ = true;
-  bool applyNDR_ = false;
   bool insertionDelay_ = true;
   bool bufferListInferred_ = false;
   bool sinkBufferInferred_ = false;
@@ -330,6 +339,7 @@ class CtsOptions : public odb::dbBlockCallBackObj
   std::string dummyload_prefix_ = "clkload";
   MasterCount dummy_count_;
   bool repairClockNets_ = false;
+  NdrStrategy ndrStrategy_ = NdrStrategy::NONE;
 };
 
 }  // namespace cts

src/cts/src/TritonCTS.cpp

@@ -481,7 +481,7 @@ void TritonCTS::writeDataToDb()
 
   for (auto& builder : builders_) {
     writeClockNetsToDb(builder.get(), clkLeafNets);
-    if (options_->applyNDR()) {
+    if (options_->getApplyNdr() != CtsOptions::NdrStrategy::NONE) {
       writeClockNDRsToDb(builder.get());
     }
     if (options_->dummyLoadEnabled()) {
@@ -1697,21 +1697,22 @@ void TritonCTS::writeClockNDRsToDb(TreeBuilder* builder)
 
   int clkNets = 0;
 
-  // TODO: Add user specified args to choose the NDR strategy
-  // Option 1: Apply NDR to specific levels
-  // const std::vector<int> specificLevels = {0};  // Apply to level 0
-  // clkNets = applyNDRToClockLevels(clockNet, clockNDR, specificLevels);
-
-  // Option 2: Apply NDR to a range of levels (e.g., Levels 0-3)
-  // clkNets = applyNDRToClockLevelRange(block_, clockNDR, clkLeafNets, 0, 3);
-
-  // Option 3: Apply NDR to the first half of the clk tree levels (higher
-  // levels)
-  // clkNets = applyNDRToFirstHalfLevels(clockNet, clockNDR);
-
-  // Option 4: Apply NDR to all non-leaf clock nets (default)
-  clkNets = applyNDRToClockLevels(
-      clockNet, clockNDR, getAllClockTreeLevels(clockNet));
+  // Apply NDR following the selected strategy (root_only, half, full)
+  switch (options_->getApplyNdr()) {
+    case CtsOptions::NdrStrategy::ROOT_ONLY:
+      clkNets = applyNDRToClockLevels(clockNet, clockNDR, {0});
+      break;
+    case CtsOptions::NdrStrategy::HALF:
+      clkNets = applyNDRToFirstHalfLevels(clockNet, clockNDR);
+      break;
+    case CtsOptions::NdrStrategy::FULL:
+      clkNets = applyNDRToClockLevels(
+          clockNet, clockNDR, getAllClockTreeLevels(clockNet));
+      break;
+    case CtsOptions::NdrStrategy::NONE:
+      // Should not be called
+      break;
+  }
 
   logger_->info(CTS,
                 202,

src/cts/src/TritonCTS.i

@@ -205,9 +205,9 @@ set_obstruction_aware(bool obs)
 }
 
 void
-set_apply_ndr(bool ndr)
+set_apply_ndr(const char* strategy)
 {
-  getTritonCts()->getParms()->setApplyNDR(ndr);
+  getTritonCts()->getParms()->setApplyNDR(strategy);
 }
 
 void

src/cts/src/TritonCTS.tcl

@@ -74,9 +74,10 @@ proc clock_tree_synthesis { args } {
           -clustering_unbalance_ratio -sink_clustering_max_diameter \
           -macro_clustering_size -macro_clustering_max_diameter \
           -sink_clustering_levels -tree_buf \
+          -apply_ndr \
           -sink_buffer_max_cap_derate -delay_buffer_derate -library} \
     flags {-post_cts_disable -sink_clustering_enable -balance_levels \
-           -obstruction_aware -no_obstruction_aware -apply_ndr \
+           -obstruction_aware -no_obstruction_aware \
            -dont_use_dummy_load -repair_clock_nets -no_insertion_delay
   } ;# checker off
 
@@ -213,7 +214,10 @@ proc clock_tree_synthesis { args } {
     cts::set_dummy_load true
   }
 
-  cts::set_apply_ndr [info exists flags(-apply_ndr)]
+  if { [info exists keys(-apply_ndr)] } {
+    set strategy $keys(-apply_ndr)
+    cts::set_apply_ndr $strategy
+  }
 
   if { [info exists flags(-repair_clock_nets)] } {
     cts::set_repair_clock_nets true