1*8d13bc63SEmmanuel Vadot// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
2*8d13bc63SEmmanuel Vadot/*
3*8d13bc63SEmmanuel Vadot * Copyright (C) 2023 Marvell International Ltd.
4*8d13bc63SEmmanuel Vadot *
5*8d13bc63SEmmanuel Vadot * Device tree for the AC5X RD Type 7 Com Express carrier board,
6*8d13bc63SEmmanuel Vadot * This specific board in external mode (see below) only maintains
7*8d13bc63SEmmanuel Vadot * a PCIe link with the COM Express CPU module, which does not
8*8d13bc63SEmmanuel Vadot * require any special DTS definitions.
9*8d13bc63SEmmanuel Vadot *
10*8d13bc63SEmmanuel Vadot * AC5X RD can either work as you would expect, as a complete standalone
11*8d13bc63SEmmanuel Vadot * box using the internal CPU, or you can move the switch on the back of
12*8d13bc63SEmmanuel Vadot * the box to "external" mode, and connect via an external cable a kit
13*8d13bc63SEmmanuel Vadot * which would allow it to use an external CPU COM Express module,
14*8d13bc63SEmmanuel Vadot * mounted on top of an interposer kit.
15*8d13bc63SEmmanuel Vadot *
16*8d13bc63SEmmanuel Vadot * So in this case, once the switch is set to external mode as explained above,
17*8d13bc63SEmmanuel Vadot * the AC5X RD becomes part of the carrier solution.
18*8d13bc63SEmmanuel Vadot * This is a development/reference solution, not a full commercial solution,
19*8d13bc63SEmmanuel Vadot * hence it was designed with the flexibility to be configured in different
20*8d13bc63SEmmanuel Vadot * modes of operation.
21*8d13bc63SEmmanuel Vadot *
22*8d13bc63SEmmanuel Vadot * When the board boots in the external CPU mode, the internal CPU is disabled,
23*8d13bc63SEmmanuel Vadot * and only the switch portion of the SOC acts as a PCIe end-point, Hence there
24*8d13bc63SEmmanuel Vadot * is no need to describe this internal (disabled CPU) in the device tree.
25*8d13bc63SEmmanuel Vadot *
26*8d13bc63SEmmanuel Vadot * There is no CPU booting in this mode on the carrier,
27*8d13bc63SEmmanuel Vadot * only on the COM Express CPU module.
28*8d13bc63SEmmanuel Vadot */
29*8d13bc63SEmmanuel Vadot
30*8d13bc63SEmmanuel Vadot/ {
31*8d13bc63SEmmanuel Vadot	model = "Marvell Armada AC5X RD COM EXPRESS type 7 carrier board";
32*8d13bc63SEmmanuel Vadot	compatible = "marvell,rd-ac5x-carrier";
33*8d13bc63SEmmanuel Vadot
34*8d13bc63SEmmanuel Vadot};
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