dt-bindings: PCI: exynos: add the samsung,exynos-pcie binding

Add dt-bindings for the Samsung Exynos PCIe controller (Exynos5433
variant). Based on the text dt-binding posted by Jaehoon Chung.

Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Marek Szyprowski <[e-mail]>
Signed-off-by: Lorenzo Pieralisi <[e-mail]>
Reviewed-by: Krzysztof Kozlowski <[e-mail]>
Reviewed-by: Rob Herring <[e-mail]>

Documentation/devicetree/bindings/pci/samsung,exynos-pcie.yaml

···
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/pci/samsung,exynos-pcie.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Samsung SoC series PCIe Host Controller Device Tree Bindings
+
+maintainers:
+  - Marek Szyprowski <[e-mail]>
+  - Jaehoon Chung <[e-mail]>
+
+description: |+
+  Exynos5433 SoC PCIe host controller is based on the Synopsys DesignWare
+  PCIe IP and thus inherits all the common properties defined in
+  designware-pcie.txt.
+
+allOf:
+  - $ref: /schemas/pci/pci-bus.yaml#
+
+properties:
+  compatible:
+    const: samsung,exynos5433-pcie
+
+  reg:
+    items:
+      - description: Data Bus Interface (DBI) registers.
+      - description: External Local Bus interface (ELBI) registers.
+      - description: PCIe configuration space region.
+
+  reg-names:
+    items:
+      - const: dbi
+      - const: elbi
+      - const: config
+
+  interrupts:
+    maxItems: 1
+
+  clocks:
+    items:
+      - description: PCIe bridge clock
+      - description: PCIe bus clock
+
+  clock-names:
+    items:
+      - const: pcie
+      - const: pcie_bus
+
+  phys:
+    maxItems: 1
+
+  vdd10-supply:
+    description:
+      Phandle to a regulator that provides 1.0V power to the PCIe block.
+
+  vdd18-supply:
+    description:
+      Phandle to a regulator that provides 1.8V power to the PCIe block.
+
+  num-lanes:
+    const: 1
+
+  num-viewport:
+    const: 3
+
+required:
+  - reg
+  - reg-names
+  - interrupts
+  - "#address-cells"
+  - "#size-cells"
+  - "#interrupt-cells"
+  - interrupt-map
+  - interrupt-map-mask
+  - ranges
+  - bus-range
+  - device_type
+  - num-lanes
+  - num-viewport
+  - clocks
+  - clock-names
+  - phys
+  - vdd10-supply
+  - vdd18-supply
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    #include <dt-bindings/clock/exynos5433.h>
+
+    pcie: pcie@15700000 {
+        compatible = "samsung,exynos5433-pcie";
+        reg = <0x15700000 0x1000>, <0x156b0000 0x1000>, <0x0c000000 0x1000>;
+        reg-names = "dbi", "elbi", "config";
+        #address-cells = <3>;
+        #size-cells = <2>;
+        #interrupt-cells = <1>;
+        device_type = "pci";
+        interrupts = <GIC_SPI 245 IRQ_TYPE_LEVEL_HIGH>;
+        clocks = <&cmu_fsys CLK_PCIE>, <&cmu_fsys CLK_PCLK_PCIE_PHY>;
+        clock-names = "pcie", "pcie_bus";
+        phys = <&pcie_phy>;
+        pinctrl-0 = <&pcie_bus &pcie_wlanen>;
+        pinctrl-names = "default";
+        num-lanes = <1>;
+        num-viewport = <3>;
+        bus-range = <0x00 0xff>;
+        ranges = <0x81000000 0 0	  0x0c001000 0 0x00010000>,
+                 <0x82000000 0 0x0c011000 0x0c011000 0 0x03feefff>;
+        vdd10-supply = <&ldo6_reg>;
+        vdd18-supply = <&ldo7_reg>;
+        interrupt-map-mask = <0 0 0 0>;
+        interrupt-map = <0 0 0 0 &gic GIC_SPI 245 IRQ_TYPE_LEVEL_HIGH>;
+    };
+...