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}; 35