arch/tile/include/asm/fixmap.h

   1 /*
   2  * Copyright (C) 1998 Ingo Molnar
   3  * Copyright 2010 Tilera Corporation. All Rights Reserved.
   4  *
   5  *   This program is free software; you can redistribute it and/or
   6  *   modify it under the terms of the GNU General Public License
   7  *   as published by the Free Software Foundation, version 2.
   8  *
   9  *   This program is distributed in the hope that it will be useful, but
  10  *   WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  12  *   NON INFRINGEMENT.  See the GNU General Public License for
  13  *   more details.
  14  */
  15
  16 #ifndef _ASM_TILE_FIXMAP_H
  17 #define _ASM_TILE_FIXMAP_H
  18
  19 #include <asm/page.h>
  20
  21 #ifndef __ASSEMBLY__
  22 #include <linux/kernel.h>
  23 #ifdef CONFIG_HIGHMEM
  24 #include <linux/threads.h>
  25 #include <asm/kmap_types.h>
  26 #endif
  27
  28 /*
  29  * Here we define all the compile-time 'special' virtual
  30  * addresses. The point is to have a constant address at
  31  * compile time, but to set the physical address only
  32  * in the boot process. We allocate these special addresses
  33  * from the end of supervisor virtual memory backwards.
  34  * Also this lets us do fail-safe vmalloc(), we
  35  * can guarantee that these special addresses and
  36  * vmalloc()-ed addresses never overlap.
  37  *
  38  * these 'compile-time allocated' memory buffers are
  39  * fixed-size 4k pages. (or larger if used with an increment
  40  * higher than 1) use fixmap_set(idx,phys) to associate
  41  * physical memory with fixmap indices.
  42  *
  43  * TLB entries of such buffers will not be flushed across
  44  * task switches.
  45  */
  46 enum fixed_addresses {
  47 #ifdef __tilegx__
  48         /*
  49          * TILEPro has unmapped memory above so the hole isn't needed,
  50          * and in any case the hole pushes us over a single 16MB pmd.
  51          */
  52         FIX_HOLE,
  53 #endif
  54 #ifdef CONFIG_HIGHMEM
  55         FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */
  56         FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1,
  57 #endif
  58 #ifdef __tilegx__  /* see homecache.c */
  59         FIX_HOMECACHE_BEGIN,
  60         FIX_HOMECACHE_END = FIX_HOMECACHE_BEGIN+(NR_CPUS)-1,
  61 #endif
  62         __end_of_permanent_fixed_addresses,
  63
  64         /*
  65          * Temporary boot-time mappings, used before ioremap() is functional.
  66          * Not currently needed by the Tile architecture.
  67          */
  68 #define NR_FIX_BTMAPS   0
  69 #if NR_FIX_BTMAPS
  70         FIX_BTMAP_END = __end_of_permanent_fixed_addresses,
  71         FIX_BTMAP_BEGIN = FIX_BTMAP_END + NR_FIX_BTMAPS - 1,
  72         __end_of_fixed_addresses
  73 #else
  74         __end_of_fixed_addresses = __end_of_permanent_fixed_addresses
  75 #endif
  76 };
  77
  78 #define __FIXADDR_SIZE  (__end_of_permanent_fixed_addresses << PAGE_SHIFT)
  79 #define __FIXADDR_BOOT_SIZE     (__end_of_fixed_addresses << PAGE_SHIFT)
  80 #define FIXADDR_START           (FIXADDR_TOP + PAGE_SIZE - __FIXADDR_SIZE)
  81 #define FIXADDR_BOOT_START      (FIXADDR_TOP + PAGE_SIZE - __FIXADDR_BOOT_SIZE)
  82
  83 #include <asm-generic/fixmap.h>
  84
  85 #endif /* !__ASSEMBLY__ */
  86
  87 #endif /* _ASM_TILE_FIXMAP_H */