[RFC PATCH 1/8] dt-bindings: phy: mediatek,xfi-pextp: add new bindings

[Daniel Golle <daniel@makrotopia.org>]

Add bindings for the MediaTek PEXTP Ethernet SerDes PHY found in the
MediaTek MT7988 SoC which can operate at various interfaces modes:

 * USXGMII
 * 10GBase-R
 * 5GBase-R
 * 2500Base-X
 * 1000Base-X
 * Cisco SGMII (MAC side)

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
---
 .../bindings/phy/mediatek,xfi-pextp.yaml      | 71 +++++++++++++++++++
 1 file changed, 71 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/phy/mediatek,xfi-pextp.yaml

diff --git a/Documentation/devicetree/bindings/phy/mediatek,xfi-pextp.yaml b/Documentation/devicetree/bindings/phy/mediatek,xfi-pextp.yaml
new file mode 100644
index 0000000000000..948d5031af1e3
--- /dev/null
+++ b/Documentation/devicetree/bindings/phy/mediatek,xfi-pextp.yaml
@@ -0,0 +1,71 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/phy/mediatek,xfi-pextp.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: MediaTek XFI PEXTP SerDes PHY
+
+maintainers:
+  - Daniel Golle <daniel@makrotopia.org>
+
+description: |
+  The MediaTek XFI PEXTP SerDes PHY provides the physical SerDes lanes
+  used by the MediaTek USXGMII PCS.
+
+properties:
+  $nodename:
+    pattern: "^phy@[0-9a-f]+$"
+
+  compatible:
+    const: mediatek,mt7988-xfi-pextp
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    items:
+      - description: XFI PHY clock
+
+  resets:
+    items:
+      - description: PEXTP reset
+
+  mediatek,usxgmii-performance-errata:
+    $ref: /schemas/types.yaml#/definitions/flag
+    description:
+      USXGMII0 on MT7988 suffers from a performance problem in 10GBase-R
+      mode which needs a work-around in the driver. The work-around is
+      enabled using this flag.
+
+  "#phy-cells":
+    const: 0
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - resets
+  - "#phy-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/mediatek,mt7988-clk.h>
+    #include <dt-bindings/reset/mediatek,mt7988-resets.h>
+    soc {
+      #address-cells = <2>;
+      #size-cells = <2>;
+
+      xfi_pextp0: phy@11f20000 {
+        compatible = "mediatek,mt7988-xfi-pextp";
+        reg = <0 0x11f20000 0 0x10000>;
+        clocks = <&topckgen CLK_TOP_XFI_PHY_0_XTAL_SEL>;
+        resets = <&watchdog MT7988_TOPRGU_XFI_PEXTP0_GRST>;
+        mediatek,usxgmii-performance-errata;
+        #phy-cells = <0>;
+      };
+    };
+
+...
-- 
2.42.1