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 <linux/sizes.h> 21 #include <asm/boot.h> 22 #include <asm/page.h> 23 24 /* 25 * Here we define all the compile-time 'special' virtual 26 * addresses. The point is to have a constant address at 27 * compile time, but to set the physical address only 28 * in the boot process. 29 * 30 * These 'compile-time allocated' memory buffers are 31 * page-sized. Use set_fixmap(idx,phys) to associate 32 * physical memory with fixmap indices. 33 * 34 */ 35 enum fixed_addresses { 36 FIX_HOLE, 37 38 /* 39 * Reserve a virtual window for the FDT that is 2 MB larger than the 40 * maximum supported size, and put it at the top of the fixmap region. 41 * The additional space ensures that any FDT that does not exceed 42 * MAX_FDT_SIZE can be mapped regardless of whether it crosses any 43 * 2 MB alignment boundaries. 44 * 45 * Keep this at the top so it remains 2 MB aligned. 46 */ 47 #define FIX_FDT_SIZE (MAX_FDT_SIZE + SZ_2M) 48 FIX_FDT_END, 49 FIX_FDT = FIX_FDT_END + FIX_FDT_SIZE / PAGE_SIZE - 1, 50 51 FIX_EARLYCON_MEM_BASE, 52 FIX_TEXT_POKE0, 53 __end_of_permanent_fixed_addresses, 54 55 /* 56 * Temporary boot-time mappings, used by early_ioremap(), 57 * before ioremap() is functional. 58 */ 59 #define NR_FIX_BTMAPS (SZ_256K / PAGE_SIZE) 60 #define FIX_BTMAPS_SLOTS 7 61 #define TOTAL_FIX_BTMAPS (NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS) 62 63 FIX_BTMAP_END = __end_of_permanent_fixed_addresses, 64 FIX_BTMAP_BEGIN = FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1, 65 66 /* 67 * Used for kernel page table creation, so unmapped memory may be used 68 * for tables. 69 */ 70 FIX_PTE, 71 FIX_PMD, 72 FIX_PUD, 73 FIX_PGD, 74 75 __end_of_fixed_addresses 76 }; 77 78 #define FIXADDR_SIZE (__end_of_permanent_fixed_addresses << PAGE_SHIFT) 79 #define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE) 80 81 #define FIXMAP_PAGE_IO __pgprot(PROT_DEVICE_nGnRE) 82 83 void __init early_fixmap_init(void); 84 85 #define __early_set_fixmap __set_fixmap 86 87 #define __late_set_fixmap __set_fixmap 88 #define __late_clear_fixmap(idx) __set_fixmap((idx), 0, FIXMAP_PAGE_CLEAR) 89 90 extern void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot); 91 92 #include <asm-generic/fixmap.h> 93 94 #endif /* !__ASSEMBLY__ */ 95 #endif /* _ASM_ARM64_FIXMAP_H */ 96