arch/microblaze/include/asm/fixmap.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * fixmap.h: compile-time virtual memory allocation
   4  *
   5  * Copyright (C) 1998 Ingo Molnar
   6  *
   7  * Copyright 2008 Freescale Semiconductor Inc.
   8  *   Port to powerpc added by Kumar Gala
   9  *
  10  * Copyright 2011 Michal Simek <monstr@monstr.eu>
  11  * Copyright 2011 PetaLogix Qld Pty Ltd
  12  *   Port to Microblaze
  13  */
  14
  15 #ifndef _ASM_FIXMAP_H
  16 #define _ASM_FIXMAP_H
  17
  18 #ifndef __ASSEMBLY__
  19 #include <linux/kernel.h>
  20 #include <asm/page.h>
  21 #ifdef CONFIG_HIGHMEM
  22 #include <linux/threads.h>
  23 #include <asm/kmap_size.h>
  24 #endif
  25
  26 #define FIXADDR_TOP     ((unsigned long)(-PAGE_SIZE))
  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 virtual memory (0xfffff000) 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  * highger 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         FIX_HOLE,
  48 #ifdef CONFIG_HIGHMEM
  49         FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */
  50         FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * num_possible_cpus()) - 1,
  51 #endif
  52         __end_of_fixed_addresses
  53 };
  54
  55 extern void __set_fixmap(enum fixed_addresses idx,
  56                                         phys_addr_t phys, pgprot_t flags);
  57
  58 #define __FIXADDR_SIZE  (__end_of_fixed_addresses << PAGE_SHIFT)
  59 #define FIXADDR_START           (FIXADDR_TOP - __FIXADDR_SIZE)
  60
  61 #define FIXMAP_PAGE_NOCACHE PAGE_KERNEL_CI
  62
  63 #include <asm-generic/fixmap.h>
  64
  65 #endif /* !__ASSEMBLY__ */
  66 #endif