[RFC PATCH net-next 8/8] dt-bindings: net: fsl,backplane-anlt: new binding document
From: Vladimir Oltean
Date: Thu Aug 17 2023 - 11:08:18 EST
Illustrate how the backplane AN/LT blocks can be instantiated on the
LX2160A SoC with SerDes protocol 19.
Signed-off-by: Vladimir Oltean <vladimir.oltean@xxxxxxx>
---
.../devicetree/bindings/net/ethernet-phy.yaml | 8 +
.../bindings/net/fsl,backplane-anlt.yaml | 238 ++++++++++++++++++
2 files changed, 246 insertions(+)
create mode 100644 Documentation/devicetree/bindings/net/fsl,backplane-anlt.yaml
diff --git a/Documentation/devicetree/bindings/net/ethernet-phy.yaml b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
index c1241c8a3b77..96fa672e4786 100644
--- a/Documentation/devicetree/bindings/net/ethernet-phy.yaml
+++ b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
@@ -49,6 +49,14 @@ properties:
- items:
- pattern: "^ethernet-phy-id[a-f0-9]{4}\\.[a-f0-9]{4}$"
- const: ethernet-phy-ieee802.3-c45
+ - items:
+ - const: fsl,lx2160a-backplane-anlt
+ - const: ethernet-phy-ieee802.3-c45
+ description:
+ Some C45 PHYs have no PHY ID in the standard location, and there is
+ also no PHY ID allocated for them to fake. They are identified by the
+ primary compatible string, plus the secondary one to distinguish them
+ from a raw MDIO device.
reg:
minimum: 0
diff --git a/Documentation/devicetree/bindings/net/fsl,backplane-anlt.yaml b/Documentation/devicetree/bindings/net/fsl,backplane-anlt.yaml
new file mode 100644
index 000000000000..7282e93b1dd4
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/fsl,backplane-anlt.yaml
@@ -0,0 +1,238 @@
+# SPDX-License-Identifier: GPL-2.0+
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/net/fsl,backplane-anlt.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Freescale Backplane Ethernet PHY
+
+maintainers:
+ - Vladimir Oltean <vladimir.oltean@xxxxxxx>
+
+description: |
+ Some QorIQ and Layerscape SoCs have an additional block on each SerDes
+ networking lane, based on an IP core from MoreThanIP, which performs IEEE
+ 802.3 clause 73 base page exchanges (for auto-negotiation) and clause 72
+ training frame exchanges (for link training).
+
+ By default, this AN/LT block comes up with auto-negotiation disabled, and
+ in that case it allows itself to be quickly bypassed from the data path and
+ for the PCS link to come up without its involvement.
+
+ Software can optionally make use of it, to turn the PCS, AN/LT block and lane
+ (PMA/PMD) into a full copper backplane internal PHY.
+
+ As a warning, the binding for the multi-lane link modes (40GBase-KR4) is not
+ currently backed up by a driver implementation.
+
+allOf:
+ - if:
+ properties:
+ compatible:
+ - items:
+ - const: fsl,lx2160a-backplane-anlt
+ - const: ethernet-phy-ieee802.3-c45
+ then:
+ $ref: ethernet-phy.yaml#
+
+properties:
+ compatible:
+ oneOf:
+ - items:
+ - const: fsl,lx2160a-backplane-anlt
+ - const: ethernet-phy-ieee802.3-c45
+ - const: fsl,lx2160a-secondary-anlt
+
+ reg:
+ minimum: 0
+ maximum: 31
+ description: |
+ The address of the AN/LT block within the internal MDIO bus of the MAC it
+ is attached to.
+
+ In the 1000Base-KX and 10GBase-KR link modes, the AN/LT block responds at
+ the same MDIO address as the PCS (determined by the SGMIInCR1[MDEV_PORT]
+ or SXGMIInCR1[MDEV_PORT] registers of the SerDes block, by default 0).
+ The PCS and AN/LT block respond to different MMDs, though.
+
+ In the 25GBase-KR and higher link modes, the AN/LT block responds at a
+ different MDIO address than the PCS, determined by the
+ ANLTnCR1[MDEV_PORT] register of the SerDes block. By default this is 4
+ for lanes A and E, 5 for lanes B and F, 6 for lanes C and G, 7 for lanes
+ D and H.
+
+ The PCS responds in all cases at the address determined by the MDEV_PORT
+ field of the SGMIInCR1, SXGMIIaCR1, E25GaCR1, E40GaCR1, E50GaCR1 or
+ E100GaCR1 registers of the SerDes block.
+
+ phys:
+ maxItems: 1
+ description:
+ phandle for the generic PHY (SerDes lane) that acts as PMA/PMD layer
+
+ pcs-handle:
+ maxItems: 1
+ description:
+ phandle for the technology-dependent PCS block corresponding to the
+ initial (RCW-based) configuration of the port. Must be omitted for the
+ link modes where the PCS and AN/LT block respond at the same MDIO
+ address. Must be specified otherwise.
+
+ secondary-anlt-handle:
+ maxItems: 1
+ description:
+ In case this is the primary (first) lane of a multi-lane link mode, this
+ property holds an array of phandles for the other AN/LT blocks, that are
+ involved in link training but not in auto-negotiation. These have the
+ "fsl,lx2160a-secondary-anlt" compatible string.
+
+required:
+ - compatible
+ - reg
+ - phys
+
+unevaluatedProperties: false
+
+examples:
+
+ # LX2160A lanes A, B, C, D with SerDes 1 protocol 19: dpmac2 uses 40GBase-KR4
+ - |
+ dpmac2 {
+ phy-handle = <&mac2_backplane_anlt>;
+ phy-connection-type = "internal";
+ };
+
+ pcs_mdio2 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "okay";
+
+ pcs2: ethernet-phy@0 {
+ reg = <0>;
+ };
+
+ mac2_backplane_anlt: ethernet-phy@7 {
+ compatible = "fsl,lx2160a-backplane-anlt",
+ "ethernet-phy-ieee802.3-c45";
+ reg = <7>; /* according to ANLTDCR1[MDEV_PORT] */
+ phys = <&serdes_1 3>; /* lane D */
+ max-speed = <40000>;
+ pcs-handle = <&pcs2>;
+ secondary-anlt-handle = <&mac2_lane2_anlt>, <&mac2_lane3_anlt>,
+ <&mac2_lane4_anlt>;
+ };
+
+ mac2_lane2_anlt: ethernet-backplane-anlt@6 {
+ compatible = "fsl,lx2160a-secondary-anlt";
+ reg = <6>; /* according to ANLTCCR1[MDEV_PORT] */
+ phys = <&serdes_1 2>; /* lane C */
+ };
+
+ mac2_lane3_anlt: ethernet-backplane-anlt@5 {
+ compatible = "fsl,lx2160a-secondary-anlt";
+ reg = <5>; /* according to ANLTBCR1[MDEV_PORT] */
+ phys = <&serdes_1 1>; /* lane B */
+ };
+
+ mac2_lane4_anlt: ethernet-backplane-anlt@4 {
+ compatible = "fsl,lx2160a-secondary-anlt";
+ reg = <4>; /* according to ANLTACR1[MDEV_PORT] */
+ phys = <&serdes_1 0>; /* lane A */
+ };
+ };
+
+ # LX2160A lane E with SerDes 1 protocol 19: dpmac6 uses 25GBase-KR
+ - |
+ dpmac6 {
+ phy-handle = <&mac6_backplane_anlt>;
+ phy-connection-type = "internal";
+ };
+
+ pcs_mdio6 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "okay";
+
+ pcs6: ethernet-phy@0 {
+ reg = <0>;
+ };
+
+ mac6_backplane_anlt: ethernet-phy@4 {
+ compatible = "fsl,lx2160a-backplane-anlt",
+ "ethernet-phy-ieee802.3-c45";
+ reg = <4>; /* according to ANLTFCR1[MDEV_PORT] */
+ phys = <&serdes_1 4>; /* lane E */
+ max-speed = <25000>;
+ pcs-handle = <&pcs6>;
+ };
+ };
+
+ # LX2160A lane F with SerDes 1 protocol 19: dpmac5 uses 25GBase-KR
+ - |
+ dpmac5 {
+ phy-handle = <&mac5_backplane_anlt>;
+ phy-connection-type = "internal";
+ };
+
+ pcs_mdio5 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "okay";
+
+ pcs5: ethernet-phy@0 {
+ reg = <0>;
+ };
+
+ mac5_backplane_anlt: ethernet-phy@5 {
+ compatible = "fsl,lx2160a-backplane-anlt",
+ "ethernet-phy-ieee802.3-c45";
+ reg = <5>; /* according to ANLTFCR1[MDEV_PORT] */
+ phys = <&serdes_1 5>; /* lane F */
+ max-speed = <25000>;
+ pcs-handle = <&pcs5>;
+ };
+ };
+
+ # LX2160A lane G with SerDes 1 protocol 19: dpmac4 uses 10GBase-KR
+ - |
+ dpmac4 {
+ phy-handle = <&mac4_backplane_anlt>;
+ phy-connection-type = "internal";
+ };
+
+ pcs_mdio4 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "okay";
+
+ mac4_backplane_anlt: ethernet-phy@0 {
+ compatible = "fsl,lx2160a-backplane-anlt",
+ "ethernet-phy-ieee802.3-c45";
+ reg = <0>; /* merged with PCS SXGMIIGCR1[MDEV_PORT] */
+ phys = <&serdes_1 7>; /* lane G */
+ max-speed = <10000>;
+ /* no pcs-handle to &pcs4 */
+ };
+ };
+
+ # LX2160A lane H with SerDes 1 protocol 19: dpmac3 uses 10GBase-KR
+ - |
+ dpmac3 {
+ phy-handle = <&mac3_backplane_anlt>;
+ phy-connection-type = "internal";
+ };
+
+ pcs_mdio3 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "okay";
+
+ mac3_backplane_anlt: ethernet-phy@0 {
+ compatible = "fsl,lx2160a-backplane-anlt",
+ "ethernet-phy-ieee802.3-c45";
+ reg = <0>; /* merged with PCS SXGMIIHCR1[MDEV_PORT] */
+ phys = <&serdes_1 7>; /* lane H */
+ max-speed = <10000>;
+ /* no pcs-handle to &pcs3 */
+ };
+ };
--
2.34.1