[PATCH v5 2/2] ARM: dts: aspeed: Add device tree for Nvidia's GB200 UT3.0b platform BMC

[Krzysztof Kozlowski]

On Fri, Jul 18, 2025 at 04:11:18PM -0700, Donald Shannon wrote:
> +
> +/ {
> +	model = "AST2600 GB200 UT3.0b BMC";
> +	compatible = "nvidia,gb200-ut30b", "aspeed,ast2600";
> +
> +	aliases {
> +		serial2 = &uart3;
> +		serial4 = &uart5;
> +		i2c16   = &imux16;
> +		i2c17   = &imux17;
> +		i2c18   = &imux18;
> +		i2c19   = &imux19;
> +		i2c20   = &imux20;
> +		i2c21   = &imux21;
> +		i2c22   = &imux22;
> +		i2c23   = &imux23;
> +		i2c24   = &imux24;
> +		i2c25   = &imux25;
> +		i2c26   = &imux26;
> +		i2c27   = &imux27;
> +		i2c28   = &imux28;
> +		i2c29   = &imux29;
> +		i2c30   = &imux30;
> +		i2c31   = &imux31;
> +		i2c32   = &imux32;
> +		i2c33   = &imux33;
> +		i2c34   = &imux34;
> +		i2c35   = &imux35;
> +		i2c36   = &imux36;
> +		i2c37   = &imux37;
> +		i2c38   = &imux38;
> +		i2c39   = &imux39;
> +		i2c40	= &e1si2c0;
> +		i2c41	= &e1si2c1;
> +		i2c42	= &e1si2c2;
> +		i2c43	= &e1si2c3;
> +		i2c48	= &i2c17mux0;
> +		i2c49	= &i2c17mux1;
> +		i2c50	= &i2c17mux2;
> +		i2c51	= &i2c17mux3;
> +		i2c52	= &i2c25mux0;
> +		i2c53	= &i2c25mux1;
> +		i2c54	= &i2c25mux2;
> +		i2c55	= &i2c25mux3;
> +		i2c56	= &i2c29mux0;
> +		i2c57	= &i2c29mux1;
> +		i2c58	= &i2c29mux2;
> +		i2c59	= &i2c29mux3;
> +	};
> +
> +	buttons {
> +		button-power {
> +			label = "power-btn";

How is this supposed to work? How does anything bind here?

> +			gpio = <&sgpiom0 156 GPIO_ACTIVE_LOW>;
> +		};
> +		button-uid {
> +			label = "uid-btn";
> +			gpio = <&sgpiom0 154 GPIO_ACTIVE_LOW>;
> +		};
> +	};
> +
> +	chosen {
> +		stdout-path = &uart5;
> +	};
> +
> +	leds {
> +		compatible = "gpio-leds";
> +		led-0 {
> +			label = "uid_led";
> +			gpios = <&sgpiom0 27 GPIO_ACTIVE_LOW>;
> +		};
> +		led-1 {
> +			label = "fault_led";
> +			gpios = <&sgpiom0 29 GPIO_ACTIVE_LOW>;
> +		};
> +		led-2 {
> +			label = "power_led";
> +			gpios = <&sgpiom0 31 GPIO_ACTIVE_LOW>;
> +		};
> +	};
> +
> +	memory at 80000000 {
> +		device_type = "memory";
> +		reg = <0x80000000 0x80000000>;
> +	};
> +
> +	reg_3v3_stby: regulator-3v3-standby {
> +		compatible = "regulator-fixed";
> +		regulator-name = "3v3-standby";
> +		regulator-min-microvolt = <1800000>;
> +		regulator-max-microvolt = <1800000>;
> +		gpio = <&gpio0 ASPEED_GPIO(M, 3) GPIO_ACTIVE_HIGH>;
> +		enable-active-high;
> +		regulator-always-on;
> +	};
> +
> +	reserved-memory {
> +		#address-cells = <1>;
> +		#size-cells = <1>;
> +		ranges;
> +
> +		vga_memory: framebuffer at 9f000000 {
> +			no-map;
> +			reg = <0x9f000000 0x01000000>; /* 16M */
> +		};
> +
> +		ramoops at a0000000 {
> +			compatible = "ramoops";
> +			reg = <0xa0000000 0x100000>; /* 1MB */
> +			record-size = <0x10000>; /* 64KB */
> +			max-reason = <2>; /* KMSG_DUMP_OOPS */
> +		};
> +
> +		gfx_memory: framebuffer {
> +			compatible = "shared-dma-pool";
> +			reusable;
> +			size = <0x01000000>;
> +			alignment = <0x01000000>;
> +		};
> +
> +		video_engine_memory: jpegbuffer {
> +			compatible = "shared-dma-pool";
> +			reusable;
> +			size = <0x02000000>;	/* 32M */
> +			alignment = <0x01000000>;
> +		};
> +	};
> +};
> +
> +// Enable Primary flash on FMC for bring up activity
> +&fmc {
> +	status = "okay";
> +	flash at 0 {
> +		compatible = "jedec,spi-nor";
> +		label = "bmc";
> +		spi-max-frequency = <50000000>;
> +		status = "okay";

Why do you need it? Anything disabled it?

Best regards,
Krzysztof