|  | /* | 
|  | * Copyright (c) 2025 Peter Johanson | 
|  | * | 
|  | * SPDX-License-Identifier: Apache-2.0 | 
|  | */ | 
|  |  | 
|  | /* | 
|  | * Be sure we don't overlap the reserved byte for storing the boot-mode | 
|  | */ | 
|  | &sram0 { | 
|  | reg = <0x20000004 ((DT_SIZE_K(264)) - 4)>; | 
|  | }; | 
|  |  | 
|  | / { | 
|  | chosen { | 
|  | zephyr,boot-mode = &boot_mode; | 
|  | }; | 
|  |  | 
|  | /* | 
|  | * Placed at the start, to avoid the bootrom clobbering our RAM, | 
|  | * with it's stack. | 
|  | */ | 
|  | sram@20000000 { | 
|  | compatible = "zephyr,memory-region", "mmio-sram"; | 
|  | reg = <0x20000000 0x4>; | 
|  | zephyr,memory-region = "RetainedMem"; | 
|  | status = "okay"; | 
|  |  | 
|  | retainedmem { | 
|  | compatible = "zephyr,retained-ram"; | 
|  | status = "okay"; | 
|  | #address-cells = <1>; | 
|  | #size-cells = <1>; | 
|  |  | 
|  | boot_mode: retention@0 { | 
|  | compatible = "zephyr,retention"; | 
|  | status = "okay"; | 
|  | reg = <0x0 0x1>; | 
|  | }; | 
|  | }; | 
|  | }; | 
|  | }; |