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

   1/*
   2 * Based on arch/arm/include/asm/memory.h
   3 *
   4 * Copyright (C) 2000-2002 Russell King
   5 * Copyright (C) 2012 ARM Ltd.
   6 *
   7 * This program is free software; you can redistribute it and/or modify
   8 * it under the terms of the GNU General Public License version 2 as
   9 * published by the Free Software Foundation.
  10 *
  11 * This program is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 * GNU General Public License for more details.
  15 *
  16 * You should have received a copy of the GNU General Public License
  17 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18 *
  19 * Note: this file should not be included by non-asm/.h files
  20 */
  21#ifndef __ASM_MEMORY_H
  22#define __ASM_MEMORY_H
  23
  24#include <linux/compiler.h>
  25#include <linux/const.h>
  26#include <linux/types.h>
  27#include <asm/sizes.h>
  28
  29/*
  30 * Allow for constants defined here to be used from assembly code
  31 * by prepending the UL suffix only with actual C code compilation.
  32 */
  33#define UL(x) _AC(x, UL)
  34
  35/*
  36 * PAGE_OFFSET - the virtual address of the start of the kernel image.
  37 * VA_BITS - the maximum number of bits for virtual addresses.
  38 * TASK_SIZE - the maximum size of a user space task.
  39 * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area.
  40 * The module space lives between the addresses given by TASK_SIZE
  41 * and PAGE_OFFSET - it must be within 128MB of the kernel text.
  42 */
  43#define PAGE_OFFSET             UL(0xffffffc000000000)
  44#define MODULES_END             (PAGE_OFFSET)
  45#define MODULES_VADDR           (MODULES_END - SZ_64M)
  46#define EARLYCON_IOBASE         (MODULES_VADDR - SZ_4M)
  47#define VA_BITS                 (39)
  48#define TASK_SIZE_64            (UL(1) << VA_BITS)
  49
  50#ifdef CONFIG_COMPAT
  51#define TASK_SIZE_32            UL(0x100000000)
  52#define TASK_SIZE               (test_thread_flag(TIF_32BIT) ? \
  53                                TASK_SIZE_32 : TASK_SIZE_64)
  54#else
  55#define TASK_SIZE               TASK_SIZE_64
  56#endif /* CONFIG_COMPAT */
  57
  58#define TASK_UNMAPPED_BASE      (PAGE_ALIGN(TASK_SIZE / 4))
  59
  60#if TASK_SIZE_64 > MODULES_VADDR
  61#error Top of 64-bit user space clashes with start of module space
  62#endif
  63
  64/*
  65 * Physical vs virtual RAM address space conversion.  These are
  66 * private definitions which should NOT be used outside memory.h
  67 * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
  68 */
  69#define __virt_to_phys(x)       (((phys_addr_t)(x) - PAGE_OFFSET + PHYS_OFFSET))
  70#define __phys_to_virt(x)       ((unsigned long)((x) - PHYS_OFFSET + PAGE_OFFSET))
  71
  72/*
  73 * Convert a physical address to a Page Frame Number and back
  74 */
  75#define __phys_to_pfn(paddr)    ((unsigned long)((paddr) >> PAGE_SHIFT))
  76#define __pfn_to_phys(pfn)      ((phys_addr_t)(pfn) << PAGE_SHIFT)
  77
  78/*
  79 * Convert a page to/from a physical address
  80 */
  81#define page_to_phys(page)      (__pfn_to_phys(page_to_pfn(page)))
  82#define phys_to_page(phys)      (pfn_to_page(__phys_to_pfn(phys)))
  83
  84/*
  85 * Memory types available.
  86 */
  87#define MT_DEVICE_nGnRnE        0
  88#define MT_DEVICE_nGnRE         1
  89#define MT_DEVICE_GRE           2
  90#define MT_NORMAL_NC            3
  91#define MT_NORMAL               4
  92
  93/*
  94 * Memory types for Stage-2 translation
  95 */
  96#define MT_S2_NORMAL            0xf
  97#define MT_S2_DEVICE_nGnRE      0x1
  98
  99#ifndef __ASSEMBLY__
 100
 101extern phys_addr_t              memstart_addr;
 102/* PHYS_OFFSET - the physical address of the start of memory. */
 103#define PHYS_OFFSET             ({ memstart_addr; })
 104
 105/*
 106 * PFNs are used to describe any physical page; this means
 107 * PFN 0 == physical address 0.
 108 *
 109 * This is the PFN of the first RAM page in the kernel
 110 * direct-mapped view.  We assume this is the first page
 111 * of RAM in the mem_map as well.
 112 */
 113#define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
 114
 115/*
 116 * Note: Drivers should NOT use these.  They are the wrong
 117 * translation for translating DMA addresses.  Use the driver
 118 * DMA support - see dma-mapping.h.
 119 */
 120static inline phys_addr_t virt_to_phys(const volatile void *x)
 121{
 122        return __virt_to_phys((unsigned long)(x));
 123}
 124
 125static inline void *phys_to_virt(phys_addr_t x)
 126{
 127        return (void *)(__phys_to_virt(x));
 128}
 129
 130/*
 131 * Drivers should NOT use these either.
 132 */
 133#define __pa(x)                 __virt_to_phys((unsigned long)(x))
 134#define __va(x)                 ((void *)__phys_to_virt((phys_addr_t)(x)))
 135#define pfn_to_kaddr(pfn)       __va((pfn) << PAGE_SHIFT)
 136
 137/*
 138 *  virt_to_page(k)     convert a _valid_ virtual address to struct page *
 139 *  virt_addr_valid(k)  indicates whether a virtual address is valid
 140 */
 141#define ARCH_PFN_OFFSET         PHYS_PFN_OFFSET
 142
 143#define virt_to_page(kaddr)     pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
 144#define virt_addr_valid(kaddr)  (((void *)(kaddr) >= (void *)PAGE_OFFSET) && \
 145                                 ((void *)(kaddr) < (void *)high_memory))
 146
 147#endif
 148
 149#include <asm-generic/memory_model.h>
 150
 151#endif
 152