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_64 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/page.h>
  21
  22 /*
  23  * Here we define all the compile-time 'special' virtual
  24  * addresses. The point is to have a constant address at
  25  * compile time, but to set the physical address only
  26  * in the boot process.
  27  *
  28  * These 'compile-time allocated' memory buffers are
  29  * page-sized. Use set_fixmap(idx,phys) to associate
  30  * physical memory with fixmap indices.
  31  *
  32  */
  33 enum fixed_addresses {
  34         FIX_HOLE,
  35         FIX_EARLYCON_MEM_BASE,
  36         __end_of_permanent_fixed_addresses,
  37
  38         /*
  39          * Temporary boot-time mappings, used by early_ioremap(),
  40          * before ioremap() is functional.
  41          */
  42 #ifdef CONFIG_ARM64_64K_PAGES
  43 #define NR_FIX_BTMAPS           4
  44 #else
  45 #define NR_FIX_BTMAPS           64
  46 #endif
  47 #define FIX_BTMAPS_SLOTS        7
  48 #define TOTAL_FIX_BTMAPS        (NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS)
  49
  50         FIX_BTMAP_END = __end_of_permanent_fixed_addresses,
  51         FIX_BTMAP_BEGIN = FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1,
  52         __end_of_fixed_addresses
  53 };
  54
  55 #define FIXADDR_SIZE    (__end_of_permanent_fixed_addresses << PAGE_SHIFT)
  56 #define FIXADDR_START   (FIXADDR_TOP - FIXADDR_SIZE)
  57
  58 #define FIXMAP_PAGE_IO     __pgprot(PROT_DEVICE_nGnRE)
  59
  60 void __init early_fixmap_init(void);
  61
  62 #define __early_set_fixmap __set_fixmap
  63
  64 extern void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot);
  65
  66 #include <asm-generic/fixmap.h>
  67
  68 #endif /* !__ASSEMBLY__ */
  69 #endif /* _ASM_ARM64_FIXMAP_H */