[PATCH v3 11/16] dt-bindings: pinctrl: Add StarFive JH7100 bindings
From: Emil Renner Berthing
Date: Tue Nov 02 2021 - 12:44:55 EST
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