dt-bindings: PCI: qcom: Specify reg-names explicitly

Instead of specifying the enum of possible reg-names, specify them
explicitly. This allows us to specify which chipsets need the "atu"
regions and which do not. Also it clearly describes which platforms
enumerate PCIe cores using the dbi region and which use parf region for
that.

Link: https://lore.kernel.org/r/20220506152107.1527552-4-dmitry.baryshkov@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>

Documentation/devicetree/bindings/pci/qcom,pcie.yaml

@@ -40,13 +40,6 @@ properties:
   reg-names:
     minItems: 4
     maxItems: 5
-    items:
-      enum:
-        - parf # Qualcomm specific registers
-        - dbi # DesignWare PCIe registers
-        - elbi # External local bus interface registers
-        - config # PCIe configuration space
-        - atu # ATU address space (optional)
 
   interrupts:
     maxItems: 1
@@ -117,6 +110,90 @@ required:
 
 allOf:
   - $ref: /schemas/pci/pci-bus.yaml#
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - qcom,pcie-apq8064
+              - qcom,pcie-ipq4019
+              - qcom,pcie-ipq8064
+              - qcom,pcie-ipq8064v2
+              - qcom,pcie-ipq8074
+              - qcom,pcie-qcs404
+    then:
+      properties:
+        reg:
+          minItems: 4
+          maxItems: 4
+        reg-names:
+          items:
+            - const: dbi # DesignWare PCIe registers
+            - const: elbi # External local bus interface registers
+            - const: parf # Qualcomm specific registers
+            - const: config # PCIe configuration space
+
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - qcom,pcie-ipq6018
+    then:
+      properties:
+        reg:
+          minItems: 5
+          maxItems: 5
+        reg-names:
+          items:
+            - const: dbi # DesignWare PCIe registers
+            - const: elbi # External local bus interface registers
+            - const: atu # ATU address space
+            - const: parf # Qualcomm specific registers
+            - const: config # PCIe configuration space
+
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - qcom,pcie-apq8084
+              - qcom,pcie-msm8996
+              - qcom,pcie-sdm845
+    then:
+      properties:
+        reg:
+          minItems: 4
+          maxItems: 4
+        reg-names:
+          items:
+            - const: parf # Qualcomm specific registers
+            - const: dbi # DesignWare PCIe registers
+            - const: elbi # External local bus interface registers
+            - const: config # PCIe configuration space
+
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - qcom,pcie-sc8180x
+              - qcom,pcie-sm8250
+              - qcom,pcie-sm8450-pcie0
+              - qcom,pcie-sm8450-pcie1
+    then:
+      properties:
+        reg:
+          minItems: 5
+          maxItems: 5
+        reg-names:
+          items:
+            - const: parf # Qualcomm specific registers
+            - const: dbi # DesignWare PCIe registers
+            - const: elbi # External local bus interface registers
+            - const: atu # ATU address space
+            - const: config # PCIe configuration space
+
   - if:
       properties:
         compatible: