1 /* 2 * Copyright (c) 2023 Nordic Semiconductor ASA 3 * 4 * SPDX-License-Identifier: Apache-2.0 5 */ 6 7 /* 8 * DESCRIPTION 9 * Platform independent set of macros for creating a memory segment for 10 * aggregating data that shall be kept in the elf file but not in the binary. 11 */ 12 13 #ifndef ZEPHYR_INCLUDE_LINKER_LINKER_DEVNULL_H_ 14 #define ZEPHYR_INCLUDE_LINKER_LINKER_DEVNULL_H_ 15 16 #if defined(CONFIG_LINKER_DEVNULL_MEMORY) 17 18 #if defined(CONFIG_XIP) 19 #if (!defined(ROM_ADDR) && !defined(ROM_BASE)) || !defined(ROM_SIZE) 20 #error "ROM_SIZE, ROM_ADDR or ROM_BASE not defined" 21 #endif 22 #endif /* CONFIG_XIP */ 23 24 #if (!defined(RAM_ADDR) && !defined(RAM_BASE)) || !defined(RAM_SIZE) 25 #error "RAM_SIZE, RAM_ADDR or RAM_BASE not defined" 26 #endif 27 28 #if defined(CONFIG_XIP) && !defined(ROM_ADDR) 29 #define ROM_ADDR ROM_BASE 30 #endif 31 32 #if !defined(RAM_ADDR) 33 #define RAM_ADDR RAM_BASE 34 #endif 35 36 #define ROM_END_ADDR (ROM_ADDR + ROM_SIZE) 37 #define DEVNULL_SIZE CONFIG_LINKER_DEVNULL_MEMORY_SIZE 38 #define ROM_DEVNULL_END_ADDR (ROM_END_ADDR + DEVNULL_SIZE) 39 #define MAX_ADDR UINT32_MAX 40 41 /* Determine where to put the devnull region. It should be adjacent to the ROM 42 * region. If ROM starts after RAM or the distance between ROM and RAM is big 43 * enough to fit the devnull region then devnull region is placed just after 44 * the ROM region. If it cannot be done then the devnull region is placed before 45 * the ROM region. It is possible that the devnull region cannot be placed 46 * adjacent to the ROM (e.g. ROM starts at 0 and RAM follows ROM). In that 47 * case compilation fails and the devnull region is not supported in that 48 * configuration. 49 */ 50 #if !defined(CONFIG_XIP) 51 52 #if RAM_ADDR >= DEVNULL_SIZE 53 #define DEVNULL_ADDR (RAM_ADDR - DEVNULL_SIZE) 54 #else 55 #define DEVNULL_ADDR (RAM_ADDR + RAM_SIZE) 56 #endif 57 58 #else /* CONFIG_XIP */ 59 60 #if ((ROM_ADDR > RAM_ADDR) && ((MAX_ADDR - ROM_END_ADDR) >= DEVNULL_SIZE)) || \ 61 ((ROM_END_ADDR + DEVNULL_SIZE) <= RAM_ADDR) 62 #define DEVNULL_ADDR ROM_END_ADDR 63 #elif ROM_ADDR > DEVNULL_SIZE 64 #define DEVNULL_ADDR (ROM_ADDR - DEVNULL_SIZE) 65 #else 66 #error "Cannot place devnull segment adjacent to ROM region." 67 #endif 68 69 #endif /* CONFIG_XIP */ 70 71 #define DEVNULL_REGION DEVNULL_ROM 72 73 #endif /* CONFIG_LINKER_DEVNULL_MEMORY */ 74 75 #endif /* ZEPHYR_INCLUDE_LINKER_LINKER_DEVNULL_H_ */ 76
