diff options
Diffstat (limited to 'Documentation/devicetree/bindings/net/dsa/sja1105.txt')
| -rw-r--r-- | Documentation/devicetree/bindings/net/dsa/sja1105.txt | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/net/dsa/sja1105.txt b/Documentation/devicetree/bindings/net/dsa/sja1105.txt new file mode 100644 index 000000000..13fd21074 --- /dev/null +++ b/Documentation/devicetree/bindings/net/dsa/sja1105.txt @@ -0,0 +1,156 @@ +NXP SJA1105 switch driver +========================= + +Required properties: + +- compatible: + Must be one of: + - "nxp,sja1105e" + - "nxp,sja1105t" + - "nxp,sja1105p" + - "nxp,sja1105q" + - "nxp,sja1105r" + - "nxp,sja1105s" + + Although the device ID could be detected at runtime, explicit bindings + are required in order to be able to statically check their validity. + For example, SGMII can only be specified on port 4 of R and S devices, + and the non-SGMII devices, while pin-compatible, are not equal in terms + of support for RGMII internal delays (supported on P/Q/R/S, but not on + E/T). + +Optional properties: + +- sja1105,role-mac: +- sja1105,role-phy: + Boolean properties that can be assigned under each port node. By + default (unless otherwise specified) a port is configured as MAC if it + is driving a PHY (phy-handle is present) or as PHY if it is PHY-less + (fixed-link specified, presumably because it is connected to a MAC). + The effect of this property (in either its implicit or explicit form) + is: + - In the case of MII or RMII it specifies whether the SJA1105 port is a + clock source or sink for this interface (not applicable for RGMII + where there is a Tx and an Rx clock). + - In the case of RGMII it affects the behavior regarding internal + delays: + 1. If sja1105,role-mac is specified, and the phy-mode property is one + of "rgmii-id", "rgmii-txid" or "rgmii-rxid", then the entity + designated to apply the delay/clock skew necessary for RGMII + is the PHY. The SJA1105 MAC does not apply any internal delays. + 2. If sja1105,role-phy is specified, and the phy-mode property is one + of the above, the designated entity to apply the internal delays + is the SJA1105 MAC (if hardware-supported). This is only supported + by the second-generation (P/Q/R/S) hardware. On a first-generation + E or T device, it is an error to specify an RGMII phy-mode other + than "rgmii" for a port that is in fixed-link mode. In that case, + the clock skew must either be added by the MAC at the other end of + the fixed-link, or by PCB serpentine traces on the board. + These properties are required, for example, in the case where SJA1105 + ports are at both ends of a MII/RMII PHY-less setup. One end would need + to have sja1105,role-mac, while the other sja1105,role-phy. + +See Documentation/devicetree/bindings/net/dsa/dsa.txt for the list of standard +DSA required and optional properties. + +Other observations +------------------ + +The SJA1105 SPI interface requires a CS-to-CLK time (t2 in UM10944) of at least +one half of t_CLK. At an SPI frequency of 1MHz, this means a minimum +cs_sck_delay of 500ns. Ensuring that this SPI timing requirement is observed +depends on the SPI bus master driver. + +Example +------- + +Ethernet switch connected via SPI to the host, CPU port wired to enet2: + +arch/arm/boot/dts/ls1021a-tsn.dts: + +/* SPI controller of the LS1021 */ +&dspi0 { + sja1105@1 { + reg = <0x1>; + #address-cells = <1>; + #size-cells = <0>; + compatible = "nxp,sja1105t"; + spi-max-frequency = <4000000>; + fsl,spi-cs-sck-delay = <1000>; + fsl,spi-sck-cs-delay = <1000>; + ports { + #address-cells = <1>; + #size-cells = <0>; + port@0 { + /* ETH5 written on chassis */ + label = "swp5"; + phy-handle = <&rgmii_phy6>; + phy-mode = "rgmii-id"; + reg = <0>; + /* Implicit "sja1105,role-mac;" */ + }; + port@1 { + /* ETH2 written on chassis */ + label = "swp2"; + phy-handle = <&rgmii_phy3>; + phy-mode = "rgmii-id"; + reg = <1>; + /* Implicit "sja1105,role-mac;" */ + }; + port@2 { + /* ETH3 written on chassis */ + label = "swp3"; + phy-handle = <&rgmii_phy4>; + phy-mode = "rgmii-id"; + reg = <2>; + /* Implicit "sja1105,role-mac;" */ + }; + port@3 { + /* ETH4 written on chassis */ + phy-handle = <&rgmii_phy5>; + label = "swp4"; + phy-mode = "rgmii-id"; + reg = <3>; + /* Implicit "sja1105,role-mac;" */ + }; + port@4 { + /* Internal port connected to eth2 */ + ethernet = <&enet2>; + phy-mode = "rgmii"; + reg = <4>; + /* Implicit "sja1105,role-phy;" */ + fixed-link { + speed = <1000>; + full-duplex; + }; + }; + }; + }; +}; + +/* MDIO controller of the LS1021 */ +&mdio0 { + /* BCM5464 */ + rgmii_phy3: ethernet-phy@3 { + reg = <0x3>; + }; + rgmii_phy4: ethernet-phy@4 { + reg = <0x4>; + }; + rgmii_phy5: ethernet-phy@5 { + reg = <0x5>; + }; + rgmii_phy6: ethernet-phy@6 { + reg = <0x6>; + }; +}; + +/* Ethernet master port of the LS1021 */ +&enet2 { + phy-connection-type = "rgmii"; + status = "ok"; + fixed-link { + speed = <1000>; + full-duplex; + }; +}; |