// 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, * This specific board in external mode (see below) only maintains * a PCIe link with the COM Express CPU module, which does not * require any special DTS definitions. * * AC5X RD can either work as you would expect, as a complete standalone * box using the internal CPU, or you can move the switch on the back of * the box to "external" mode, and connect via an external cable a kit * which would allow it to use an external 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. * This is a development/reference solution, not a full commercial solution, * hence it was designed with the flexibility to be configured in different * modes of operation. * * 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 COM Express CPU module. */ / { model = "Marvell Armada AC5X RD COM EXPRESS type 7 carrier board"; compatible = "marvell,rd-ac5x-carrier"; };