Fixup pathfinder pktflow sorting by sorting on src coords and port on…

…ly (#1777) Co-authored-by: Jeff Fifield <jeff.fifield@amd.com>
Xilinx · Sep 18, 2024 · 5821674 · 5821674
1 parent e90b275
commit 5821674
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Showing 3 changed files with 30 additions and 56 deletions.
diff --git a/include/aie/Dialect/AIE/Transforms/AIEPathFinder.h b/include/aie/Dialect/AIE/Transforms/AIEPathFinder.h
@@ -252,6 +252,9 @@ class DynamicTileAnalysis {
   ShimMuxOp getShimMux(mlir::OpBuilder &builder, int col);
 };
 
+// Get enum int value from WireBundle.
+int getWireBundleAsInt(WireBundle bundle);
+
 } // namespace xilinx::AIE
 
 namespace llvm {

diff --git a/lib/Dialect/AIE/Transforms/AIECreatePathFindFlows.cpp b/lib/Dialect/AIE/Transforms/AIECreatePathFindFlows.cpp
@@ -445,50 +445,23 @@ void AIEPathfinderPass::runOnPacketFlow(DeviceOp device, OpBuilder &builder) {
         return -1;
       };
 
-  // To get determinsitic behaviour; allocate amsels for control packet flows
-  // before others
-  auto getWireBundleAsInt = [](WireBundle bundle) {
-    switch (bundle) {
-    case WireBundle::Core:
-      return 0;
-    case WireBundle::DMA:
-      return 1;
-    case WireBundle::FIFO:
-      return 2;
-    case WireBundle::South:
-      return 3;
-    case WireBundle::West:
-      return 4;
-    case WireBundle::North:
-      return 5;
-    case WireBundle::East:
-      return 6;
-    case WireBundle::PLIO:
-      return 7;
-    case WireBundle::NOC:
-      return 8;
-    case WireBundle::Trace:
-      return 9;
-    case WireBundle::Ctrl:
-      return 10;
+  // Sorting the packet flows in order to get determinsitic amsel allocation;
+  // allocate amsels for control packet flows before others to ensure
+  // consistency in control packet flow overlay.
+  auto getUniqueIdPerFlowPerSB = [](int flowID, WireBundle srcBundle,
+                                    SmallVector<PhysPort, 4> dests) {
+    int totalNumOfWireBundles = AIE::getMaxEnumValForWireBundle();
+    int currMultiplier = totalNumOfWireBundles;
+    int uniqueId = flowID;
+    uniqueId += currMultiplier + getWireBundleAsInt(srcBundle);
+    currMultiplier += totalNumOfWireBundles;
+    for (auto dst : dests) {
+      uniqueId += currMultiplier;
+      uniqueId += getWireBundleAsInt(dst.second.bundle);
+      currMultiplier += totalNumOfWireBundles;
     }
-    return -1;
+    return uniqueId;
   };
-  auto getUniqueIdPerFlowPerSB =
-      [getWireBundleAsInt](int flowID, WireBundle srcBundle,
-                           SmallVector<PhysPort, 4> dests) {
-        int totalNumOfWireBundles = AIE::getMaxEnumValForWireBundle();
-        int currMultiplier = totalNumOfWireBundles;
-        int uniqueId = flowID;
-        uniqueId += currMultiplier + getWireBundleAsInt(srcBundle);
-        currMultiplier += totalNumOfWireBundles;
-        for (auto dst : dests) {
-          uniqueId += currMultiplier;
-          uniqueId += getWireBundleAsInt(dst.second.bundle);
-          currMultiplier += totalNumOfWireBundles;
-        }
-        return uniqueId;
-      };
   auto getSortedPacketFlows =
       [&](DenseMap<std::pair<PhysPort, int>, SmallVector<PhysPort, 4>> pktFlows,
           DenseMap<std::pair<PhysPort, int>, SmallVector<PhysPort, 4>>

diff --git a/lib/Dialect/AIE/Transforms/AIEPathFinder.cpp b/lib/Dialect/AIE/Transforms/AIEPathFinder.cpp
@@ -357,22 +357,15 @@ void Pathfinder::sortFlows(const int maxCol, const int maxRow) {
             [maxCol, maxRow](const auto &lhs, const auto &rhs) {
               int lhsUniqueID = lhs.src.coords.col;
               lhsUniqueID += lhs.src.coords.row * maxCol;
-              int currMultiplier = maxCol * maxRow;
-              for (auto dest : lhs.dsts) {
-                lhsUniqueID += currMultiplier;
-                lhsUniqueID += dest.coords.col;
-                lhsUniqueID += dest.coords.row * maxCol;
-                currMultiplier += maxCol * maxRow;
-              }
+              lhsUniqueID += maxRow * maxCol;
+              lhsUniqueID += getWireBundleAsInt(lhs.src.port.bundle);
+              lhsUniqueID += AIE::getMaxEnumValForWireBundle();
+              lhsUniqueID += lhs.src.port.channel;
               int rhsUniqueID = rhs.src.coords.col;
               rhsUniqueID += rhs.src.coords.row * maxCol;
-              currMultiplier = maxCol * maxRow;
-              for (auto dest : rhs.dsts) {
-                rhsUniqueID += currMultiplier;
-                rhsUniqueID += dest.coords.col;
-                rhsUniqueID += dest.coords.row * maxCol;
-                currMultiplier += maxCol * maxRow;
-              }
+              rhsUniqueID += maxRow * maxCol;
+              rhsUniqueID += getWireBundleAsInt(rhs.src.port.bundle);
+              rhsUniqueID += rhs.src.port.channel;
               return lhsUniqueID < rhsUniqueID;
             });
   flows = priorityFlows;
@@ -693,3 +686,8 @@ Pathfinder::findPaths(const int maxIterations) {
   LLVM_DEBUG(llvm::dbgs() << "\t---End Pathfinder::findPaths---\n");
   return routingSolution;
 }
+
+// Get enum int value from WireBundle.
+int AIE::getWireBundleAsInt(WireBundle bundle) {
+  return static_cast<typename std::underlying_type<WireBundle>::type>(bundle);
+}