1 /* 2 * fixmap.h: compile-time virtual memory allocation 3 * 4 * This file is subject to the terms and conditions of the GNU General Public 5 * License. See the file "COPYING" in the main directory of this archive 6 * for more details. 7 * 8 * Copyright (C) 1998 Ingo Molnar 9 * Copyright (C) 2013 Mark Salter <msalter@redhat.com> 10 * 11 * Adapted from arch/x86 version. 12 * 13 */ 14 15 #ifndef _ASM_ARM64_FIXMAP_H 16 #define _ASM_ARM64_FIXMAP_H 17 18 #ifndef __ASSEMBLY__ 19 #include <linux/kernel.h> 20 #include <asm/boot.h> 21 #include <asm/page.h> 22 23 /* 24 * Here we define all the compile-time 'special' virtual 25 * addresses. The point is to have a constant address at 26 * compile time, but to set the physical address only 27 * in the boot process. 28 * 29 * These 'compile-time allocated' memory buffers are 30 * page-sized. Use set_fixmap(idx,phys) to associate 31 * physical memory with fixmap indices. 32 * 33 */ 34 enum fixed_addresses { 35 FIX_HOLE, 36 37 /* 38 * Reserve a virtual window for the FDT that is 2 MB larger than the 39 * maximum supported size, and put it at the top of the fixmap region. 40 * The additional space ensures that any FDT that does not exceed 41 * MAX_FDT_SIZE can be mapped regardless of whether it crosses any 42 * 2 MB alignment boundaries. 43 * 44 * Keep this at the top so it remains 2 MB aligned. 45 */ 46 #define FIX_FDT_SIZE (MAX_FDT_SIZE + SZ_2M) 47 FIX_FDT_END, 48 FIX_FDT = FIX_FDT_END + FIX_FDT_SIZE / PAGE_SIZE - 1, 49 50 FIX_EARLYCON_MEM_BASE, 51 FIX_TEXT_POKE0, 52 __end_of_permanent_fixed_addresses, 53 54 /* 55 * Temporary boot-time mappings, used by early_ioremap(), 56 * before ioremap() is functional. 57 */ 58 #ifdef CONFIG_ARM64_64K_PAGES 59 #define NR_FIX_BTMAPS 4 60 #else 61 #define NR_FIX_BTMAPS 64 62 #endif 63 #define FIX_BTMAPS_SLOTS 7 64 #define TOTAL_FIX_BTMAPS (NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS) 65 66 FIX_BTMAP_END = __end_of_permanent_fixed_addresses, 67 FIX_BTMAP_BEGIN = FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1, 68 __end_of_fixed_addresses 69 }; 70 71 #define FIXADDR_SIZE (__end_of_permanent_fixed_addresses << PAGE_SHIFT) 72 #define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE) 73 74 #define FIXMAP_PAGE_IO __pgprot(PROT_DEVICE_nGnRE) 75 76 void __init early_fixmap_init(void); 77 78 #define __early_set_fixmap __set_fixmap 79 80 #define __late_set_fixmap __set_fixmap 81 #define __late_clear_fixmap(idx) __set_fixmap((idx), 0, FIXMAP_PAGE_CLEAR) 82 83 extern void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot); 84 85 #include <asm-generic/fixmap.h> 86 87 #endif /* !__ASSEMBLY__ */ 88 #endif /* _ASM_ARM64_FIXMAP_H */ 89