dt-bindings: pci: apple,pcie: Add t6020 compatible string

t6020 adds some register ranges compared to t8103, so requires
a new compatible as well as the new PHY registers themselves.

Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
[maz: added PHY registers]
Signed-off-by: Marc Zyngier <maz@kernel.org>

Author: alyssarosenzweig

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

@@ -17,6 +17,10 @@ description: |
   implements its root ports.  But the ATU found on most DesignWare
   PCIe host bridges is absent.
 
+  On systems derived from T602x, the PHY registers are in a region
+  separate from the port registers. In that case, there is one PHY
+  register range per port register range.
+
   All root ports share a single ECAM space, but separate GPIOs are
   used to take the PCI devices on those ports out of reset.  Therefore
   the standard "reset-gpios" and "max-link-speed" properties appear on
@@ -35,11 +39,12 @@ properties:
           - apple,t8103-pcie
           - apple,t8112-pcie
           - apple,t6000-pcie
+          - apple,t6020-pcie
       - const: apple,pcie
 
   reg:
     minItems: 3
-    maxItems: 6
+    maxItems: 10
 
   reg-names:
     minItems: 3
@@ -50,6 +55,10 @@ properties:
       - const: port1
       - const: port2
       - const: port3
+      - const: phy0
+      - const: phy1
+      - const: phy2
+      - const: phy3
 
   ranges:
     minItems: 2