This commit adds bindings document of Aspeed PECI adapter for ASPEED AST24xx/25xx/26xx SoCs. Cc: Mark Rutland <mark.rutland@xxxxxxx> Cc: Joel Stanley <joel@xxxxxxxxx> Cc: Andrew Jeffery <andrew@xxxxxxxx> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: Jason M Biils <jason.m.bills@xxxxxxxxxxxxxxx> Cc: Milton Miller II <miltonm@xxxxxxxxxx> Cc: Pavel Machek <pavel@xxxxxx> Cc: Robin Murphy <robin.murphy@xxxxxxx> Cc: Ryan Chen <ryan_chen@xxxxxxxxxxxxxx> Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@xxxxxxxxxxxxxxx> --- Changes since v10: - Changed documents format to DT schema format so I dropped all review tags. Please review it again. .../devicetree/bindings/peci/peci-aspeed.yaml | 124 ++++++++++++++++++ 1 file changed, 124 insertions(+) create mode 100644 Documentation/devicetree/bindings/peci/peci-aspeed.yaml diff --git a/Documentation/devicetree/bindings/peci/peci-aspeed.yaml b/Documentation/devicetree/bindings/peci/peci-aspeed.yaml new file mode 100644 index 000000000000..0f5c2993fe9b --- /dev/null +++ b/Documentation/devicetree/bindings/peci/peci-aspeed.yaml @@ -0,0 +1,124 @@ +# SPDX-License-Identifier: GPL-2.0 +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/peci/peci-aspeed.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Aspeed PECI Bus Device Tree Bindings + +maintainers: + - Jae Hyun Yoo <jae.hyun.yoo@xxxxxxxxxxxxxxx> + +properties: + compatible: + enum: + - aspeed,ast2400-peci + - aspeed,ast2500-peci + - aspeed,ast2600-peci + + reg: + maxItems: 1 + + "#address-cells": + # Required to define a client address. + const: 1 + + "#size-cells": + # Required to define a client address. + const: 0 + + interrupts: + maxItems: 1 + + clocks: + description: | + Clock source for PECI controller. Should reference the external + oscillator clock. + maxItems: 1 + + resets: + maxItems: 1 + + clock-frequency: + # Operation frequency of PECI controller in units of Hz. + minimum: 187500 + maximum: 24000000 + + msg-timing: + description: | + Message timing negotiation period. This value will determine the period + of message timing negotiation to be issued by PECI controller. The unit + of the programmed value is four times of PECI clock period. + allOf: + - $ref: /schemas/types.yaml#/definitions/uint32 + - minimum: 0 + maximum: 255 + default: 1 + + addr-timing: + description: | + Address timing negotiation period. This value will determine the period + of address timing negotiation to be issued by PECI controller. The unit + of the programmed value is four times of PECI clock period. + allOf: + - $ref: /schemas/types.yaml#/definitions/uint32 + - minimum: 0 + maximum: 255 + default: 1 + + rd-sampling-point: + description: | + Read sampling point selection. The whole period of a bit time will be + divided into 16 time frames. This value will determine the time frame + in which the controller will sample PECI signal for data read back. + Usually in the middle of a bit time is the best. + allOf: + - $ref: /schemas/types.yaml#/definitions/uint32 + - minimum: 0 + maximum: 15 + default: 8 + + cmd-timeout-ms: + # Command timeout in units of ms. + allOf: + - $ref: /schemas/types.yaml#/definitions/uint32 + - minimum: 1 + maximum: 60000 + default: 1000 + +required: + - compatible + - reg + - "#address-cells" + - "#size-cells" + - interrupts + - clocks + - resets + - clock-frequency + +examples: + - | + #include <dt-bindings/interrupt-controller/arm-gic.h> + #include <dt-bindings/clock/ast2600-clock.h> + peci: bus@1e78b000 { + compatible = "simple-bus"; + #address-cells = <1>; + #size-cells = <1>; + ranges = <0x0 0x1e78b000 0x60>; + + peci0: peci-bus@0 { + compatible = "aspeed,ast2600-peci"; + reg = <0x0 0x100>; + #address-cells = <1>; + #size-cells = <0>; + interrupts = <GIC_SPI 38 IRQ_TYPE_LEVEL_HIGH>; + clocks = <&syscon ASPEED_CLK_GATE_REF0CLK>; + resets = <&syscon ASPEED_RESET_PECI>; + clock-frequency = <24000000>; + msg-timing = <1>; + addr-timing = <1>; + rd-sampling-point = <8>; + cmd-timeout-ms = <1000>; + }; + }; +... -- 2.17.1