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 VA_BITS                 (39)
  47 #define TASK_SIZE_64            (UL(1) << VA_BITS)
  48
  49 #ifdef CONFIG_COMPAT
  50 #define TASK_SIZE_32            UL(0x100000000)
  51 #define TASK_SIZE               (test_thread_flag(TIF_32BIT) ? \
  52                                 TASK_SIZE_32 : TASK_SIZE_64)
  53 #else
  54 #define TASK_SIZE               TASK_SIZE_64
  55 #endif /* CONFIG_COMPAT */
  56
  57 #define TASK_UNMAPPED_BASE      (PAGE_ALIGN(TASK_SIZE / 4))
  58
  59 #if TASK_SIZE_64 > MODULES_VADDR
  60 #error Top of 64-bit user space clashes with start of module space
  61 #endif
  62
  63 /*
  64  * Physical vs virtual RAM address space conversion.  These are
  65  * private definitions which should NOT be used outside memory.h
  66  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
  67  */
  68 #define __virt_to_phys(x)       (((phys_addr_t)(x) - PAGE_OFFSET + PHYS_OFFSET))
  69 #define __phys_to_virt(x)       ((unsigned long)((x) - PHYS_OFFSET + PAGE_OFFSET))
  70
  71 /*
  72  * Convert a physical address to a Page Frame Number and back
  73  */
  74 #define __phys_to_pfn(paddr)    ((unsigned long)((paddr) >> PAGE_SHIFT))
  75 #define __pfn_to_phys(pfn)      ((phys_addr_t)(pfn) << PAGE_SHIFT)
  76
  77 /*
  78  * Convert a page to/from a physical address
  79  */
  80 #define page_to_phys(page)      (__pfn_to_phys(page_to_pfn(page)))
  81 #define phys_to_page(phys)      (pfn_to_page(__phys_to_pfn(phys)))
  82
  83 /*
  84  * Memory types available.
  85  */
  86 #define MT_DEVICE_nGnRnE        0
  87 #define MT_DEVICE_nGnRE         1
  88 #define MT_DEVICE_GRE           2
  89 #define MT_NORMAL_NC            3
  90 #define MT_NORMAL               4
  91
  92 #ifndef __ASSEMBLY__
  93
  94 extern phys_addr_t              memstart_addr;
  95 /* PHYS_OFFSET - the physical address of the start of memory. */
  96 #define PHYS_OFFSET             ({ memstart_addr; })
  97
  98 /*
  99  * PFNs are used to describe any physical page; this means
 100  * PFN 0 == physical address 0.
 101  *
 102  * This is the PFN of the first RAM page in the kernel
 103  * direct-mapped view.  We assume this is the first page
 104  * of RAM in the mem_map as well.
 105  */
 106 #define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
 107
 108 /*
 109  * Note: Drivers should NOT use these.  They are the wrong
 110  * translation for translating DMA addresses.  Use the driver
 111  * DMA support - see dma-mapping.h.
 112  */
 113 static inline phys_addr_t virt_to_phys(const volatile void *x)
 114 {
 115         return __virt_to_phys((unsigned long)(x));
 116 }
 117
 118 static inline void *phys_to_virt(phys_addr_t x)
 119 {
 120         return (void *)(__phys_to_virt(x));
 121 }
 122
 123 /*
 124  * Drivers should NOT use these either.
 125  */
 126 #define __pa(x)                 __virt_to_phys((unsigned long)(x))
 127 #define __va(x)                 ((void *)__phys_to_virt((phys_addr_t)(x)))
 128 #define pfn_to_kaddr(pfn)       __va((pfn) << PAGE_SHIFT)
 129
 130 /*
 131  *  virt_to_page(k)     convert a _valid_ virtual address to struct page *
 132  *  virt_addr_valid(k)  indicates whether a virtual address is valid
 133  */
 134 #define ARCH_PFN_OFFSET         PHYS_PFN_OFFSET
 135
 136 #define virt_to_page(kaddr)     pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
 137 #define virt_addr_valid(kaddr)  (((void *)(kaddr) >= (void *)PAGE_OFFSET) && \
 138                                  ((void *)(kaddr) < (void *)high_memory))
 139
 140 #endif
 141
 142 #include <asm-generic/memory_model.h>
 143
 144 #endif