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 #include <asm/pgtable-prot.h> 24 25 /* 26 * Here we define all the compile-time 'special' virtual 27 * addresses. The point is to have a constant address at 28 * compile time, but to set the physical address only 29 * in the boot process. 30 * 31 * These 'compile-time allocated' memory buffers are 32 * page-sized. Use set_fixmap(idx,phys) to associate 33 * physical memory with fixmap indices. 34 * 35 */ 36 enum fixed_addresses { 37 FIX_HOLE, 38 39 /* 40 * Reserve a virtual window for the FDT that is 2 MB larger than the 41 * maximum supported size, and put it at the top of the fixmap region. 42 * The additional space ensures that any FDT that does not exceed 43 * MAX_FDT_SIZE can be mapped regardless of whether it crosses any 44 * 2 MB alignment boundaries. 45 * 46 * Keep this at the top so it remains 2 MB aligned. 47 */ 48 #define FIX_FDT_SIZE (MAX_FDT_SIZE + SZ_2M) 49 FIX_FDT_END, 50 FIX_FDT = FIX_FDT_END + FIX_FDT_SIZE / PAGE_SIZE - 1, 51 52 FIX_EARLYCON_MEM_BASE, 53 FIX_TEXT_POKE0, 54 55 #ifdef CONFIG_ACPI_APEI_GHES 56 /* Used for GHES mapping from assorted contexts */ 57 FIX_APEI_GHES_IRQ, 58 FIX_APEI_GHES_NMI, 59 #endif /* CONFIG_ACPI_APEI_GHES */ 60 61 __end_of_permanent_fixed_addresses, 62 63 /* 64 * Temporary boot-time mappings, used by early_ioremap(), 65 * before ioremap() is functional. 66 */ 67 #define NR_FIX_BTMAPS (SZ_256K / PAGE_SIZE) 68 #define FIX_BTMAPS_SLOTS 7 69 #define TOTAL_FIX_BTMAPS (NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS) 70 71 FIX_BTMAP_END = __end_of_permanent_fixed_addresses, 72 FIX_BTMAP_BEGIN = FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1, 73 74 /* 75 * Used for kernel page table creation, so unmapped memory may be used 76 * for tables. 77 */ 78 FIX_PTE, 79 FIX_PMD, 80 FIX_PUD, 81 FIX_PGD, 82 83 __end_of_fixed_addresses 84 }; 85 86 #define FIXADDR_SIZE (__end_of_permanent_fixed_addresses << PAGE_SHIFT) 87 #define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE) 88 89 #define FIXMAP_PAGE_IO __pgprot(PROT_DEVICE_nGnRE) 90 91 void __init early_fixmap_init(void); 92 93 #define __early_set_fixmap __set_fixmap 94 95 #define __late_set_fixmap __set_fixmap 96 #define __late_clear_fixmap(idx) __set_fixmap((idx), 0, FIXMAP_PAGE_CLEAR) 97 98 extern void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot); 99 100 #include <asm-generic/fixmap.h> 101 102 #endif /* !__ASSEMBLY__ */ 103 #endif /* _ASM_ARM64_FIXMAP_H */ 104