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 #ifdef CONFIG_UNMAP_KERNEL_AT_EL0 62 FIX_ENTRY_TRAMP_DATA, 63 FIX_ENTRY_TRAMP_TEXT, 64 #define TRAMP_VALIAS (__fix_to_virt(FIX_ENTRY_TRAMP_TEXT)) 65 #endif /* CONFIG_UNMAP_KERNEL_AT_EL0 */ 66 __end_of_permanent_fixed_addresses, 67 68 /* 69 * Temporary boot-time mappings, used by early_ioremap(), 70 * before ioremap() is functional. 71 */ 72 #define NR_FIX_BTMAPS (SZ_256K / PAGE_SIZE) 73 #define FIX_BTMAPS_SLOTS 7 74 #define TOTAL_FIX_BTMAPS (NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS) 75 76 FIX_BTMAP_END = __end_of_permanent_fixed_addresses, 77 FIX_BTMAP_BEGIN = FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1, 78 79 /* 80 * Used for kernel page table creation, so unmapped memory may be used 81 * for tables. 82 */ 83 FIX_PTE, 84 FIX_PMD, 85 FIX_PUD, 86 FIX_PGD, 87 88 __end_of_fixed_addresses 89 }; 90 91 #define FIXADDR_SIZE (__end_of_permanent_fixed_addresses << PAGE_SHIFT) 92 #define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE) 93 94 #define FIXMAP_PAGE_IO __pgprot(PROT_DEVICE_nGnRE) 95 96 void __init early_fixmap_init(void); 97 98 #define __early_set_fixmap __set_fixmap 99 100 #define __late_set_fixmap __set_fixmap 101 #define __late_clear_fixmap(idx) __set_fixmap((idx), 0, FIXMAP_PAGE_CLEAR) 102 103 extern void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot); 104 105 #include <asm-generic/fixmap.h> 106 107 #endif /* !__ASSEMBLY__ */ 108 #endif /* _ASM_ARM64_FIXMAP_H */ 109