LXR linux/arch/arm64/include/asm/fixmap.h

   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 * Each enum increment in these 'compile-time allocated'
  32 * memory buffers is page-sized. Use set_fixmap(idx,phys)
  33 * to associate physical memory with a fixmap index.
  34 */
  35enum 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
  54#ifdef CONFIG_ACPI_APEI_GHES
  55        /* Used for GHES mapping from assorted contexts */
  56        FIX_APEI_GHES_IRQ,
  57        FIX_APEI_GHES_SEA,
  58#ifdef CONFIG_ARM_SDE_INTERFACE
  59        FIX_APEI_GHES_SDEI_NORMAL,
  60        FIX_APEI_GHES_SDEI_CRITICAL,
  61#endif
  62#endif /* CONFIG_ACPI_APEI_GHES */
  63
  64#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
  65        FIX_ENTRY_TRAMP_DATA,
  66        FIX_ENTRY_TRAMP_TEXT,
  67#define TRAMP_VALIAS            (__fix_to_virt(FIX_ENTRY_TRAMP_TEXT))
  68#endif /* CONFIG_UNMAP_KERNEL_AT_EL0 */
  69        __end_of_permanent_fixed_addresses,
  70
  71        /*
  72         * Temporary boot-time mappings, used by early_ioremap(),
  73         * before ioremap() is functional.
  74         */
  75#define NR_FIX_BTMAPS           (SZ_256K / PAGE_SIZE)
  76#define FIX_BTMAPS_SLOTS        7
  77#define TOTAL_FIX_BTMAPS        (NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS)
  78
  79        FIX_BTMAP_END = __end_of_permanent_fixed_addresses,
  80        FIX_BTMAP_BEGIN = FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1,
  81
  82        /*
  83         * Used for kernel page table creation, so unmapped memory may be used
  84         * for tables.
  85         */
  86        FIX_PTE,
  87        FIX_PMD,
  88        FIX_PUD,
  89        FIX_PGD,
  90
  91        __end_of_fixed_addresses
  92};
  93
  94#define FIXADDR_SIZE    (__end_of_permanent_fixed_addresses << PAGE_SHIFT)
  95#define FIXADDR_START   (FIXADDR_TOP - FIXADDR_SIZE)
  96
  97#define FIXMAP_PAGE_IO     __pgprot(PROT_DEVICE_nGnRE)
  98
  99void __init early_fixmap_init(void);
 100
 101#define __early_set_fixmap __set_fixmap
 102
 103#define __late_set_fixmap __set_fixmap
 104#define __late_clear_fixmap(idx) __set_fixmap((idx), 0, FIXMAP_PAGE_CLEAR)
 105
 106extern void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot);
 107
 108#include <asm-generic/fixmap.h>
 109
 110#endif /* !__ASSEMBLY__ */
 111#endif /* _ASM_ARM64_FIXMAP_H */
 112