arch/arm64/boot/dts/marvell/ac5x-rd-carrier-cn9131.dts

Source file repositories/reference/linux-study-clean/arch/arm64/boot/dts/marvell/ac5x-rd-carrier-cn9131.dts

File Facts

System
Linux kernel
Corpus path
arch/arm64/boot/dts/marvell/ac5x-rd-carrier-cn9131.dts
Extension
.dts
Size
1706 bytes
Lines
45
Domain
Architecture Layer
Bucket
arch/arm64
Inferred role
Architecture Layer: configuration, schema, or hardware description
Status
atlas-only

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
/*
 * Copyright (C) 2023 Marvell International Ltd.
 *
 * Device tree for the AC5X RD Type 7 Com Express carrier board,
 * Utilizing the CN913x COM Express CPU module board.
 * This specific carrier board in this mode of operation (external)
 * only maintains a PCIe link with the CPU module,
 * which does not require any special DTS definitions.
 *
 * AC5X RD works here in external mode (switch selectable at the back of the
 * board), and connect via an external cable a kit
 * which would allow it to use an external CN9131 CPU COM Express module,
 * mounted on top of an interposer kit.
 *
 * So in this case, once the switch is set to external mode as explained above,
 * the AC5X RD becomes part of the carrier solution.
 *
 * When the board boots in the external CPU mode, the internal CPU is disabled,
 * and only the switch portion of the SOC acts as a PCIe end-point, Hence there
 * is no need to describe this internal (disabled CPU) in the device tree.
 *
 * There is no CPU booting in this mode on the carrier, only on the
 * CN9131 COM Express CPU module.
 * What runs the Linux is the CN9131 on the COM Express CPU module,
 * And it accesses the switch end-point on the AC5X RD portion of the carrier
 * via PCIe.
 */

#include "cn9131-db-comexpress.dtsi"
#include "ac5x-rd-carrier.dtsi"

/ {
	model = "Marvell Armada AC5X RD COM EXPRESS type 7 carrier board with CN9131 CPU module";
	compatible = "marvell,cn9131-ac5x-carrier", "marvell,rd-ac5x-carrier",
			"marvell,cn9131-cpu-module", "marvell,cn9131",
			"marvell,armada-ap807-quad", "marvell,armada-ap807";

	memory@0 {
		device_type = "memory";
		reg = <0x0 0x0 0x2 0x00000000>;
	};

};

Annotation

Implementation Notes