Implement fat-tree topology and add routing table generation support

shashankov · shashankov · commit 74c2c1f8b589 · 2026-06-01T00:29:39.000-04:00
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diff --git a/routing_tables/gen_fattree_table.py b/routing_tables/gen_fattree_table.py
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+#!/usr/bin/python
+
+import os
+import sys
+
+if __name__ == "__main__":
+    if (len(sys.argv) != 4):
+        print("Usage (k-ary n-tree Fat Tree): " + sys.argv[0] + " <K> <N> <file_prefix>")
+        sys.exit(1)
+
+    K = int(sys.argv[1])
+    N = int(sys.argv[2])
+    table_prefix = sys.argv[3]
+
+    # Create folder if it doesn't exist
+    if not os.path.exists(table_prefix):
+        os.makedirs(table_prefix)
+
+    for level in range(N):
+        for router in range(K ** (N - 1)):
+            table_file = open("%s/%0d_%0d.hex" % (table_prefix, level, router), "w")
+            for dest_endpoint in range(K ** N):
+                if level == N - 1:
+                    # Root level: only down ports (0 to K-1)
+                    dest_port = (dest_endpoint // (K ** level)) % K
+                else:
+                    # Check if dest_endpoint is in the subtree of switch (level, router)
+                    is_in_subtree = True
+                    for check_level in range(level, N - 1):
+                        dest_digit = (dest_endpoint // (K ** (check_level + 1))) % K
+                        router_digit = (router // (K ** check_level)) % K
+                        if dest_digit != router_digit:
+                            is_in_subtree = False
+                            break
+                    
+                    if is_in_subtree:
+                        # Route down: port is d_level
+                        dest_port = (dest_endpoint // (K ** level)) % K
+                    else:
+                        # Route up: port is K + p_up.
+                        # We use (dest_endpoint // (K ** level)) % K to distribute traffic
+                        upward_port_offset = (dest_endpoint // (K ** level)) % K
+                        dest_port = K + upward_port_offset
+                table_file.write("%x\n" % (dest_port))
+            table_file.close()
diff --git a/src/topologies/axis_fat_tree.sv b/src/topologies/axis_fat_tree.sv
diff --git a/src/topologies/fat_tree.sv b/src/topologies/fat_tree.sv
diff --git a/test/axis_topology_wrapper.sv b/test/axis_topology_wrapper.sv
diff --git a/test/generate_load_latency.py b/test/generate_load_latency.py

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