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+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/net/pcs/snps,dw-xpcs.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Synopsys DesignWare Ethernet PCS
+
+maintainers:
+ - Serge Semin <fancer.lancer@gmail.com>
+
+description:
+ Synopsys DesignWare Ethernet Physical Coding Sublayer provides an interface
+ between Media Access Control and Physical Medium Attachment Sublayer through
+ the Media Independent Interface (XGMII, USXGMII, XLGMII, GMII, etc)
+ controlled by means of the IEEE std. Clause 45 registers set. The PCS can be
+ optionally synthesized with a vendor-specific interface connected to
+ Synopsys PMA (also called DesignWare Consumer/Enterprise PHY) although in
+ general it can be used to communicate with any compatible PHY.
+
+ The PCS CSRs can be accessible either over the Ethernet MDIO bus or directly
+ by means of the APB3/MCI interfaces. In the later case the XPCS can be mapped
+ right to the system IO memory space.
+
+properties:
+ compatible:
+ oneOf:
+ - description: Synopsys DesignWare XPCS with none or unknown PMA
+ const: snps,dw-xpcs
+ - description: Synopsys DesignWare XPCS with Consumer Gen1 3G PMA
+ const: snps,dw-xpcs-gen1-3g
+ - description: Synopsys DesignWare XPCS with Consumer Gen2 3G PMA
+ const: snps,dw-xpcs-gen2-3g
+ - description: Synopsys DesignWare XPCS with Consumer Gen2 6G PMA
+ const: snps,dw-xpcs-gen2-6g
+ - description: Synopsys DesignWare XPCS with Consumer Gen4 3G PMA
+ const: snps,dw-xpcs-gen4-3g
+ - description: Synopsys DesignWare XPCS with Consumer Gen4 6G PMA
+ const: snps,dw-xpcs-gen4-6g
+ - description: Synopsys DesignWare XPCS with Consumer Gen5 10G PMA
+ const: snps,dw-xpcs-gen5-10g
+ - description: Synopsys DesignWare XPCS with Consumer Gen5 12G PMA
+ const: snps,dw-xpcs-gen5-12g
+
+ reg:
+ items:
+ - description:
+ In case of the MDIO management interface this just a 5-bits ID
+ of the MDIO bus device. If DW XPCS CSRs space is accessed over the
+ MCI or APB3 management interfaces, then the space mapping can be
+ either 'direct' or 'indirect'. In the former case all Clause 45
+ registers are contiguously mapped within the address space
+ MMD '[20:16]', Reg '[15:0]'. In the later case the space is divided
+ to the multiple 256 register sets. There is a special viewport CSR
+ which is responsible for the set selection. The upper part of
+ the CSR address MMD+REG[20:8] is supposed to be written in there
+ so the corresponding subset would be mapped to the lowest 255 CSRs.
+
+ reg-names:
+ items:
+ - enum: [ direct, indirect ]
+
+ reg-io-width:
+ description:
+ The way the CSRs are mapped to the memory is platform depended. Since
+ each Clause 45 CSR is of 16-bits wide the access instructions must be
+ two bytes aligned at least.
+ default: 2
+ enum: [ 2, 4 ]
+
+ interrupts:
+ description:
+ System interface interrupt output (sbd_intr_o) indicating Clause 73/37
+ auto-negotiation events':' Page received, AN is completed or incompatible
+ link partner.
+ maxItems: 1
+
+ clocks:
+ description:
+ The MCI and APB3 interfaces are supposed to be equipped with a clock
+ source connected to the clk_csr_i line.
+
+ PCS/PMA layer can be clocked by an internal reference clock source
+ (phyN_core_refclk) or by an externally connected (phyN_pad_refclk) clock
+ generator. Both clocks can be supplied at a time.
+ minItems: 1
+ maxItems: 3
+
+ clock-names:
+ oneOf:
+ - minItems: 1
+ items: # MDIO
+ - enum: [core, pad]
+ - const: pad
+ - minItems: 1
+ items: # MCI or APB
+ - const: csr
+ - enum: [core, pad]
+ - const: pad
+
+required:
+ - compatible
+ - reg
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/interrupt-controller/irq.h>
+
+ ethernet-pcs@1f05d000 {
+ compatible = "snps,dw-xpcs";
+ reg = <0x1f05d000 0x1000>;
+ reg-names = "indirect";
+
+ reg-io-width = <4>;
+
+ interrupts = <79 IRQ_TYPE_LEVEL_HIGH>;
+
+ clocks = <&ccu_pclk>, <&ccu_core>, <&ccu_pad>;
+ clock-names = "csr", "core", "pad";
+ };
+ - |
+ mdio-bus {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ ethernet-pcs@0 {
+ compatible = "snps,dw-xpcs";
+ reg = <0>;
+
+ clocks = <&ccu_core>, <&ccu_pad>;
+ clock-names = "core", "pad";
+ };
+ };
+...
Synopsys DesignWare XPCS IP-core is a Physical Coding Sublayer (PCS) layer providing an interface between the Media Access Control (MAC) and Physical Medium Attachment Sublayer (PMA) through a Media independent interface. From software point of view it exposes IEEE std. Clause 45 CSR space and can be accessible either by MDIO or MCI/APB3 bus interfaces. In the former case the PCS device is supposed to be defined under the respective MDIO bus DT-node. In the later case the DW xPCS will be just a normal IO memory-mapped device. Besides of that DW XPCS DT-nodes can have an interrupt signal and clock source properties specified. The former one indicates the Clause 73/37 auto-negotiation events like: negotiation page received, AN is completed or incompatible link partner. The clock DT-properties can describe up to three clock sources: peripheral bus clock source, internal reference clock and the externally connected reference clock. Finally the DW XPCS IP-core can be optionally synthesized with a vendor-specific interface connected to the Synopsys PMA (also called DesignWare Consumer/Enterprise PHY). Alas that isn't auto-detectable in a portable way. So if the DW XPCS device has the respective PMA attached then it should be reflected in the DT-node compatible string so the driver would be aware of the PMA-specific device capabilities (mainly connected with CSRs available for the fine-tunings). Signed-off-by: Serge Semin <fancer.lancer@gmail.com> --- Changelog v2: - Drop the Management Interface DT-node bindings. DW xPCS with MCI/APB3 interface is just a normal memory-mapped device. Changelog v3: - Implement the ordered clocks constraint. (@Rob) Changelog v4: - Add a comment to the clock-names property constraint about the oneOf-subschemas applicability. (@Conor) - Convert "pclk" clock name to "csr" to match the DW XPCS IP-core input signal name. (@Rob) --- .../bindings/net/pcs/snps,dw-xpcs.yaml | 136 ++++++++++++++++++ 1 file changed, 136 insertions(+) create mode 100644 Documentation/devicetree/bindings/net/pcs/snps,dw-xpcs.yaml