diff --git a/yaml/xyz/openbmc_project/Inventory/Item/Cpu.interface.yaml b/yaml/xyz/openbmc_project/Inventory/Item/Cpu.interface.yaml
index fa241bf..0d5b03a 100644
--- a/yaml/xyz/openbmc_project/Inventory/Item/Cpu.interface.yaml
+++ b/yaml/xyz/openbmc_project/Inventory/Item/Cpu.interface.yaml
@@ -75,3 +75,13 @@
         - name: PowerPerformanceControl
           description: >
               Support power/performance control.
+
+associations:
+    - name: associated_pcie_slots
+      description: >
+          Objects that implement Cpu can optionally implement the
+          associated_pcie_slots association to provide a link to one or more
+          PCIe slots.
+      reverse_name: upstream_processor
+      required_endpoint_interfaces:
+        - xyz.openbmc_project.Inventory.Item.PCIeSlot
diff --git a/yaml/xyz/openbmc_project/Inventory/Item/PCIeSlot.interface.yaml b/yaml/xyz/openbmc_project/Inventory/Item/PCIeSlot.interface.yaml
index 0cc41d2..570514e 100644
--- a/yaml/xyz/openbmc_project/Inventory/Item/PCIeSlot.interface.yaml
+++ b/yaml/xyz/openbmc_project/Inventory/Item/PCIeSlot.interface.yaml
@@ -97,3 +97,13 @@
         - name: 'Unknown'
           description: >
               Type of the PCIe slot is unknown
+
+associations:
+    - name: upstream_processor
+      description: >
+          Objects that implement PCIeSlot can optionally implement the
+          upstream_processor association to provide a link back to a PCIe host
+          bridge or on-processor PCIe root complexes.
+      reverse_name: associated_pcie_slots
+      required_endpoint_interfaces:
+        - xyz.openbmc_project.Inventory.Item.Cpu