On Mon, Aug 12, 2024 at 02:05:26PM +0200, Christian Bruel wrote: > Document the bindings for STM32 COMBOPHY interface, used to support > the PCIe and USB3 stm32mp25 drivers. > Following entries can be used to tune caracterisation parameters > - st,output-micro-ohms and st,output-vswing-microvolt bindings entries > to tune the impedance and voltage swing using discrete simulation results > - st, phy_rx0_eq register to set the internal rx equalizer filter value. > > Signed-off-by: Christian Bruel <christian.bruel@xxxxxxxxxxx> > --- > .../bindings/phy/st,stm32-combophy.yaml | 178 ++++++++++++++++++ > 1 file changed, 178 insertions(+) > create mode 100644 Documentation/devicetree/bindings/phy/st,stm32-combophy.yaml > > diff --git a/Documentation/devicetree/bindings/phy/st,stm32-combophy.yaml b/Documentation/devicetree/bindings/phy/st,stm32-combophy.yaml > new file mode 100644 > index 0000000000000..6a53ab834b2a7 > --- /dev/null > +++ b/Documentation/devicetree/bindings/phy/st,stm32-combophy.yaml > @@ -0,0 +1,178 @@ > +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) > +%YAML 1.2 > +--- > +$id: http://devicetree.org/schemas/phy/st,stm32-combophy.yaml# > +$schema: http://devicetree.org/meta-schemas/core.yaml# > + > +title: STMicroelectronics STM32MP25 USB3/PCIe COMBOPHY > + > +maintainers: > + - Christian Bruel <christian.bruel@xxxxxxxxxxx> > + > +description: | Don't need '|' if no formatting to preserve. > + Single lane PHY shared (exclusive) between the USB3 and PCIe controllers. > + Supports 5Gbit/s for USB3 and PCIe gen2 or 2.5Gbit/s for PCIe gen1. > + > +properties: > + compatible: > + const: st,stm32mp25-combophy > + > + reg: > + maxItems: 1 > + > + st,syscfg: Order is standard properties first, vendor properties second. > + $ref: /schemas/types.yaml#/definitions/phandle-array > + description: Phandle to the SYSCON entry required for configuring PCIe > + or USB3. You need constraints on the size of the phandle-array or perhaps this should be just 'phandle'. > + > + "#phy-cells": > + const: 1 > + description: | > + The cells contain the following arguments. > + > + - description: The PHY type > + enum: > + - PHY_TYPE_USB3 > + - PHY_TYPE_PCIE > + > + clocks: > + anyOf: Should be 'items' > + - description: apb-clk Bus clock mandatory to access registers. > + - description: ker-clk Internal RCC reference clock for USB3 or PCIe > + - description: pad-clk Optional on board clock input for PCIe only. Typically an > + external 100Mhz oscillator wired on dedicated CLKIN pad. Used as reference > + clock input instead of the ker-clk > + > + clock-names: > + oneOf: > + - items: > + - const: apb-clk > + - const: ker-clk > + > + - items: > + - const: apb-clk > + - const: ker-clk > + - const: pad-clk Don't need oneOf here. Just add 'minItems: 2' on the 2nd entry. '-clk' is also redundant. Drop. > + > + resets: > + maxItems: 1 > + > + reset-names: > + const: phy-rst > + > + power-domains: > + maxItems: 1 > + > + st,ssc-on: > + type: boolean > + description: > + A boolean property whose presence indicates that the SSC for common clock > + needs to be set. > + > + st,rx_equalizer: s/_/-/ > + $ref: /schemas/types.yaml#/definitions/uint32 > + minimum: 0 That's already the minimum. Drop. > + maximum: 7 > + default: 2 > + description: > + A 3 bit value describing internal filter settings for the RX equalizer. How does one decide what value to use? > + > + st,output-micro-ohms: > + minimum: 3999000 > + maximum: 6090000 > + default: 4968000 > + description: > + A value property to tune the Single Ended Output Impedance, simulations results > + at 25C for a VDDP=0.8V. The hardware accepts discrete values in this range. > + > + st,output-vswing-microvolt: > + minimum: 442000 > + maximum: 803000 > + default: 803000 > + description: > + A value property in microvolt to tune the Single Ended Output Voltage Swing to change the > + Vlo, Vhi for a VDDP = 0.8V. The hardware accepts discrete values in this range. > + > + wakeup-source: true > + > + interrupts: > + maxItems: 1 > + description: interrupt used for wakeup > + > + access-controllers: > + minItems: 1 > + maxItems: 2 > + > +required: > + - compatible > + - reg > + - st,syscfg > + - '#phy-cells' > + - resets > + - reset-names > + - clocks > + - clock-names > + > +allOf: > + - if: > + required: > + - wakeup-source > + then: > + anyOf: > + - required: [interrupts] > + - required: [interrupts-extended] > + > +additionalProperties: false > + > +examples: > + - | > + // Example 1: COMBOPHY configured to use internal reference clock > + #include <dt-bindings/clock/st,stm32mp25-rcc.h> > + #include <dt-bindings/interrupt-controller/arm-gic.h> > + #include <dt-bindings/reset/st,stm32mp25-rcc.h> > + > + combophy_internal: phy@480c0000 { > + compatible = "st,stm32mp25-combophy"; > + reg = <0x480c0000 0x1000>; > + #phy-cells = <1>; > + clocks = <&rcc CK_BUS_USB3PCIEPHY>, <&rcc CK_KER_USB3PCIEPHY>; > + clock-names = "apb-clk", "ker-clk"; > + resets = <&rcc USB3PCIEPHY_R>; > + reset-names = "phy-rst"; > + st,syscfg = <&syscfg>; > + access-controllers = <&rifsc 67>; > + power-domains = <&CLUSTER_PD>; > + wakeup-source; > + interrupts-extended = <&exti1 45 IRQ_TYPE_EDGE_FALLING>; > + }; > + > + - | > + // Example 2: COMBOPHY configured to use extrenal 100MHz reference clock > + // on CLKIN pad for PCIe > + #include <dt-bindings/clock/st,stm32mp25-rcc.h> > + #include <dt-bindings/interrupt-controller/arm-gic.h> > + #include <dt-bindings/reset/st,stm32mp25-rcc.h> > + > + clocks { > + pad_clk: pad-clk { > + #clock-cells = <0>; > + compatible = "fixed-clock"; > + clock-frequency = <100000000>; > + }; > + }; Drop. Providers aren't relevant to this binding. Though just 1 optional clock doesn't justify a whole other example. So drop one of the examples. > + > + combophy_pad: phy@480c0000 { > + compatible = "st,stm32mp25-combophy"; > + reg = <0x480c0000 0x1000>; > + #phy-cells = <1>; > + clocks = <&rcc CK_BUS_USB3PCIEPHY>, <&rcc CK_KER_USB3PCIEPHY>, <&pad_clk>; > + clock-names = "apb-clk", "ker-clk", "pad-clk"; > + resets = <&rcc USB3PCIEPHY_R>; > + reset-names = "phy-rst"; > + st,syscfg = <&syscfg>; > + access-controllers = <&rifsc 67>; > + power-domains = <&CLUSTER_PD>; > + wakeup-source; > + interrupts-extended = <&exti1 45 IRQ_TYPE_EDGE_FALLING>; > + }; > +... > -- > 2.34.1 >
