[net-next PATCH v4 1/6] Documentation: ACPI: DSD: Document MDIO PHY
From: Calvin Johnson <hidden>
Date: 2020-07-09 17:58:02
Also in:
linux-acpi
Subsystem:
acpi, the rest · Maintainers:
"Rafael J. Wysocki", Linus Torvalds
Introduce ACPI mechanism to get PHYs registered on a MDIO bus and provide them to be connected to MAC. An ACPI node property "mdio-handle" is introduced to reference the MDIO bus on which PHYs are registered with autoprobing method used by mdiobus_register(). Describe properties "phy-channel" and "phy-mode" Signed-off-by: Calvin Johnson <redacted> --- Changes in v4: None Changes in v3: - cleanup based on v2 comments - Added description for more properties - Added MDIO node DSDT entry Changes in v2: None Documentation/firmware-guide/acpi/dsd/phy.rst | 90 +++++++++++++++++++ 1 file changed, 90 insertions(+) create mode 100644 Documentation/firmware-guide/acpi/dsd/phy.rst
diff --git a/Documentation/firmware-guide/acpi/dsd/phy.rst b/Documentation/firmware-guide/acpi/dsd/phy.rst
new file mode 100644
index 000000000000..0132fee10b45
--- /dev/null
+++ b/Documentation/firmware-guide/acpi/dsd/phy.rst@@ -0,0 +1,90 @@ +.. SPDX-License-Identifier: GPL-2.0 + +========================= +MDIO bus and PHYs in ACPI +========================= + +The PHYs on an mdiobus are probed and registered using mdiobus_register(). +Later, for connecting these PHYs to MAC, the PHYs registered on the +mdiobus have to be referenced. + +mdio-handle +----------- +For each MAC node, a property "mdio-handle" is used to reference the +MDIO bus on which the PHYs are registered. On getting hold of the MDIO +bus, use find_phy_device() to get the PHY connected to the MAC. + +phy-channel +----------- +Property "phy-channel" defines the address of the PHY on the mdiobus. + +phy-mode +-------- +Property "phy-mode" defines the type of PHY interface. + +An example of this is shown below:: + +DSDT entry for MAC where MDIO node is referenced +------------------------------------------------ + Scope(\_SB.MCE0.PR17) // 1G + { + Name (_DSD, Package () { + ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), + Package () { + Package () {"phy-channel", 1}, + Package () {"phy-mode", "rgmii-id"}, + Package () {"mdio-handle", Package (){\_SB.MDI0}} + } + }) + } + + Scope(\_SB.MCE0.PR18) // 1G + { + Name (_DSD, Package () { + ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), + Package () { + Package () {"phy-channel", 2}, + Package () {"phy-mode", "rgmii-id"}, + Package () {"mdio-handle", Package (){\_SB.MDI0}} + } + }) + } + +DSDT entry for MDIO node +------------------------ +a) Silicon Component +-------------------- + Scope(_SB) + { + Device(MDI0) { + Name(_HID, "NXP0006") + Name(_CCA, 1) + Name(_UID, 0) + Name(_CRS, ResourceTemplate() { + Memory32Fixed(ReadWrite, MDI0_BASE, MDI_LEN) + Interrupt(ResourceConsumer, Level, ActiveHigh, Shared) + { + MDI0_IT + } + }) // end of _CRS for MDI0 + Name (_DSD, Package () { + ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), + Package () { + Package () {"little-endian", 1}, + } + }) + } // end of MDI0 + } + +b) Platform Component +--------------------- + Scope(\_SB.MDI0) + { + Device(PHY1) { + Name (_ADR, 0x1) + } // end of PHY1 + + Device(PHY2) { + Name (_ADR, 0x2) + } // end of PHY2 + }
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2.17.1