Add bindings for the GPIO/pin controller on the JH7100 RISC-V SoC by StarFive Ltd. This is a test chip for their upcoming JH7110 SoC. Signed-off-by: Emil Renner Berthing <kernel@xxxxxxxx> --- @Linus: I'm really struggling to find a good way to describe how pin muxing works on the JH7100. As you can see I've now resorted to ascii-art to try to explain it, but please let me know if it's still unclear. .../pinctrl/starfive,jh7100-pinctrl.yaml | 307 ++++++++++++++++++ 1 file changed, 307 insertions(+) create mode 100644 Documentation/devicetree/bindings/pinctrl/starfive,jh7100-pinctrl.yaml diff --git a/Documentation/devicetree/bindings/pinctrl/starfive,jh7100-pinctrl.yaml b/Documentation/devicetree/bindings/pinctrl/starfive,jh7100-pinctrl.yaml new file mode 100644 index 000000000000..92963604422f --- /dev/null +++ b/Documentation/devicetree/bindings/pinctrl/starfive,jh7100-pinctrl.yaml @@ -0,0 +1,307 @@ +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/pinctrl/starfive,jh7100-pinctrl.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: StarFive JH7100 Pin Controller Device Tree Bindings + +description: | + Bindings for the JH7100 RISC-V SoC from StarFive Ltd. + + Out of the SoC's many pins only the ones named PAD_GPIO[0] to PAD_GPIO[63] + and PAD_FUNC_SHARE[0] to PAD_FUNC_SHARE[141] can be multiplexed and have + configurable bias, drive strength, schmitt trigger etc. The SoC has an + interesting 2-layered approach to pin muxing best illustrated by the diagram + below. + + Signal group 0, 1, ... or 6 + ___|___ + | | + LCD output -----------------| | + CMOS Camera interface ------| |--- PAD_GPIO[0] + Ethernet PHY interface -----| MUX |--- PAD_GPIO[1] + ... | | ... + | |--- PAD_GPIO[63] + -------- GPIO0 ------------| | + | -------|-- GPIO1 --------| |--- PAD_FUNC_SHARE[0] + | | | | | |--- PAD_FUNC_SHARE[1] + | | | | ... | | ... + | | | | | |--- PAD_FUNC_SHARE[141] + | | -----|---|-- GPIO63 ---| | + | | | | | | ------- + UART0 UART1 -- + + + The big MUX in the diagram only has 7 different ways of mapping peripherals + on the left to pins on the right. StarFive calls the 7 configurations "signal + groups". + However some peripherals have their I/O go through the 64 "GPIOs". The + diagram only shows UART0 and UART1, but this also includes a number of other + UARTs, I2Cs, SPIs, PWMs etc. All these peripherals are connected to all 64 + GPIOs such that any GPIO can be set up to be controlled by any of the + peripherals. + Note that signal group 0 doesn't map any of the GPIOs to pins, and only + signal group 1 maps the GPIOs to the pins named PAD_GPIO[0] to PAD_GPIO[63]. + +maintainers: + - Emil Renner Berthing <kernel@xxxxxxxx> + - Drew Fustini <drew@xxxxxxxxxxxxxxx> + +properties: + compatible: + const: starfive,jh7100-pinctrl + + reg: + minItems: 2 + maxItems: 2 + + reg-names: + items: + - const: gpio + - const: padctl + + clocks: + maxItems: 1 + + resets: + maxItems: 1 + + gpio-controller: true + + "#gpio-cells": + const: 2 + + interrupts: + maxItems: 1 + description: The GPIO parent interrupt. + + interrupt-controller: true + + "#interrupt-cells": + const: 2 + + starfive,signal-group: + description: | + Select one of the 7 signal groups. If this property is not set it + defaults to the configuration already chosen by the earlier boot stages. + $ref: /schemas/types.yaml#/definitions/uint32 + enum: [0, 1, 2, 3, 4, 5, 6] + +required: + - compatible + - reg + - reg-names + - clocks + - gpio-controller + - "#gpio-cells" + - interrupts + - interrupt-controller + - "#interrupt-cells" + +patternProperties: + '-[0-9]+$': + type: object + patternProperties: + '-pins$': + type: object + description: | + A pinctrl node should contain at least one subnode representing the + pinctrl groups available on the machine. Each subnode will list the + pins it needs, and how they should be configured, with regard to + muxer configuration, bias, input enable/disable, input schmitt + trigger enable/disable, slew-rate and drive strength. + $ref: "/schemas/pinctrl/pincfg-node.yaml" + + properties: + pins: + description: | + The list of pin identifiers that properties in the node apply to. + This should be set using either the PAD_GPIO or PAD_FUNC_SHARE + macros. + Either this or "pinmux" has to be specified, but not both. + $ref: "/schemas/pinctrl/pinmux-node.yaml#/properties/pins" + + pinmux: + description: | + The list of GPIOs and their mux settings that properties in the + node apply to. This should be set using the GPIOMUX macro. + Either this or "pins" has to be specified, but not both. + $ref: "/schemas/pinctrl/pinmux-node.yaml#/properties/pinmux" + + bias-disable: true + + bias-pull-up: + type: boolean + + bias-pull-down: + type: boolean + + drive-strength: + enum: [ 14, 21, 28, 35, 42, 49, 56, 63 ] + + input-enable: true + + input-disable: true + + input-schmitt-enable: true + + input-schmitt-disable: true + + slew-rate: + maximum: 7 + + starfive,strong-pull-up: + description: enable strong pull-up. + type: boolean + + additionalProperties: false + + additionalProperties: false + +additionalProperties: false + +examples: + - | + #include <dt-bindings/clock/starfive-jh7100.h> + #include <dt-bindings/reset/starfive-jh7100.h> + #include <dt-bindings/pinctrl/pinctrl-starfive.h> + + soc { + #address-cells = <2>; + #size-cells = <2>; + + pinctrl@11910000 { + compatible = "starfive,jh7100-pinctrl"; + reg = <0x0 0x11910000 0x0 0x10000>, + <0x0 0x11858000 0x0 0x1000>; + reg-names = "gpio", "padctl"; + clocks = <&clkgen JH7100_CLK_GPIO_APB>; + resets = <&clkgen JH7100_RSTN_GPIO_APB>; + interrupts = <32>; + gpio-controller; + #gpio-cells = <2>; + interrupt-controller; + #interrupt-cells = <2>; + starfive,signal-group = <6>; + + gmac_pins_default: gmac-0 { + gtxclk-pins { + pins = <PAD_FUNC_SHARE(115)>; + bias-pull-up; + drive-strength = <35>; + input-enable; + input-schmitt-enable; + slew-rate = <0>; + }; + miitxclk-pins { + pins = <PAD_FUNC_SHARE(116)>; + bias-pull-up; + drive-strength = <14>; + input-enable; + input-schmitt-disable; + slew-rate = <0>; + }; + tx-pins { + pins = <PAD_FUNC_SHARE(117)>, + <PAD_FUNC_SHARE(119)>, + <PAD_FUNC_SHARE(120)>, + <PAD_FUNC_SHARE(121)>, + <PAD_FUNC_SHARE(122)>, + <PAD_FUNC_SHARE(123)>, + <PAD_FUNC_SHARE(124)>, + <PAD_FUNC_SHARE(125)>, + <PAD_FUNC_SHARE(126)>; + bias-disable; + drive-strength = <35>; + input-disable; + input-schmitt-disable; + slew-rate = <0>; + }; + rxclk-pins { + pins = <PAD_FUNC_SHARE(127)>; + bias-pull-up; + drive-strength = <14>; + input-enable; + input-schmitt-disable; + slew-rate = <6>; + }; + rxer-pins { + pins = <PAD_FUNC_SHARE(129)>; + bias-pull-up; + drive-strength = <14>; + input-enable; + input-schmitt-disable; + slew-rate = <0>; + }; + rx-pins { + pins = <PAD_FUNC_SHARE(128)>, + <PAD_FUNC_SHARE(130)>, + <PAD_FUNC_SHARE(131)>, + <PAD_FUNC_SHARE(132)>, + <PAD_FUNC_SHARE(133)>, + <PAD_FUNC_SHARE(134)>, + <PAD_FUNC_SHARE(135)>, + <PAD_FUNC_SHARE(136)>, + <PAD_FUNC_SHARE(137)>, + <PAD_FUNC_SHARE(138)>, + <PAD_FUNC_SHARE(139)>, + <PAD_FUNC_SHARE(140)>, + <PAD_FUNC_SHARE(141)>; + bias-pull-up; + drive-strength = <14>; + input-enable; + input-schmitt-enable; + slew-rate = <0>; + }; + }; + + i2c0_pins_default: i2c0-0 { + i2c-pins { + pinmux = <GPIOMUX(62, GPO_LOW, + GPO_I2C0_PAD_SCK_OEN, + GPI_I2C0_PAD_SCK_IN)>, + <GPIOMUX(61, GPO_LOW, + GPO_I2C0_PAD_SDA_OEN, + GPI_I2C0_PAD_SDA_IN)>; + bias-disable; /* external pull-up */ + input-enable; + input-schmitt-enable; + }; + }; + + uart3_pins_default: uart3-0 { + rx-pins { + pinmux = <GPIOMUX(13, GPO_LOW, GPO_DISABLE, + GPI_UART3_PAD_SIN)>; + bias-pull-up; + input-enable; + input-schmitt-enable; + }; + tx-pins { + pinmux = <GPIOMUX(14, GPO_UART3_PAD_SOUT, + GPO_ENABLE, GPI_NONE)>; + bias-disable; + input-disable; + input-schmitt-disable; + }; + }; + }; + + gmac { + pinctrl-0 = <&gmac_pins_default>; + pinctrl-names = "default"; + }; + + i2c0 { + pinctrl-0 = <&i2c0_pins_default>; + pinctrl-names = "default"; + }; + + uart3 { + pinctrl-0 = <&uart3_pins_default>; + pinctrl-names = "default"; + }; + }; + +... -- 2.33.1
