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  * Size of the PCI I/O space. This must remain a power of two so that
  37  * IO_SPACE_LIMIT acts as a mask for the low bits of I/O addresses.
  38  */
  39 #define PCI_IO_SIZE             SZ_16M
  40
  41 /*
  42  * PAGE_OFFSET - the virtual address of the start of the kernel image (top
  43  *               (VA_BITS - 1))
  44  * VA_BITS - the maximum number of bits for virtual addresses.
  45  * TASK_SIZE - the maximum size of a user space task.
  46  * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area.
  47  * The module space lives between the addresses given by TASK_SIZE
  48  * and PAGE_OFFSET - it must be within 128MB of the kernel text.
  49  */
  50 #define VA_BITS                 (CONFIG_ARM64_VA_BITS)
  51 #define PAGE_OFFSET             (UL(0xffffffffffffffff) << (VA_BITS - 1))
  52 #define MODULES_END             (PAGE_OFFSET)
  53 #define MODULES_VADDR           (MODULES_END - SZ_64M)
  54 #define PCI_IO_END              (MODULES_VADDR - SZ_2M)
  55 #define PCI_IO_START            (PCI_IO_END - PCI_IO_SIZE)
  56 #define FIXADDR_TOP             (PCI_IO_START - SZ_2M)
  57 #define TASK_SIZE_64            (UL(1) << VA_BITS)
  58
  59 #ifdef CONFIG_COMPAT
  60 #define TASK_SIZE_32            UL(0x100000000)
  61 #define TASK_SIZE               (test_thread_flag(TIF_32BIT) ? \
  62                                 TASK_SIZE_32 : TASK_SIZE_64)
  63 #define TASK_SIZE_OF(tsk)       (test_tsk_thread_flag(tsk, TIF_32BIT) ? \
  64                                 TASK_SIZE_32 : TASK_SIZE_64)
  65 #else
  66 #define TASK_SIZE               TASK_SIZE_64
  67 #endif /* CONFIG_COMPAT */
  68
  69 #define TASK_UNMAPPED_BASE      (PAGE_ALIGN(TASK_SIZE / 4))
  70
  71 #if TASK_SIZE_64 > MODULES_VADDR
  72 #error Top of 64-bit user space clashes with start of module space
  73 #endif
  74
  75 /*
  76  * Physical vs virtual RAM address space conversion.  These are
  77  * private definitions which should NOT be used outside memory.h
  78  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
  79  */
  80 #define __virt_to_phys(x)       (((phys_addr_t)(x) - PAGE_OFFSET + PHYS_OFFSET))
  81 #define __phys_to_virt(x)       ((unsigned long)((x) - PHYS_OFFSET + PAGE_OFFSET))
  82
  83 /*
  84  * Convert a page to/from a physical address
  85  */
  86 #define page_to_phys(page)      (__pfn_to_phys(page_to_pfn(page)))
  87 #define phys_to_page(phys)      (pfn_to_page(__phys_to_pfn(phys)))
  88
  89 /*
  90  * Memory types available.
  91  */
  92 #define MT_DEVICE_nGnRnE        0
  93 #define MT_DEVICE_nGnRE         1
  94 #define MT_DEVICE_GRE           2
  95 #define MT_NORMAL_NC            3
  96 #define MT_NORMAL               4
  97
  98 /*
  99  * Memory types for Stage-2 translation
 100  */
 101 #define MT_S2_NORMAL            0xf
 102 #define MT_S2_DEVICE_nGnRE      0x1
 103
 104 #ifndef __ASSEMBLY__
 105
 106 extern phys_addr_t              memstart_addr;
 107 /* PHYS_OFFSET - the physical address of the start of memory. */
 108 #define PHYS_OFFSET             ({ memstart_addr; })
 109
 110 /*
 111  * The maximum physical address that the linear direct mapping
 112  * of system RAM can cover. (PAGE_OFFSET can be interpreted as
 113  * a 2's complement signed quantity and negated to derive the
 114  * maximum size of the linear mapping.)
 115  */
 116 #define MAX_MEMBLOCK_ADDR       ({ memstart_addr - PAGE_OFFSET - 1; })
 117
 118 /*
 119  * PFNs are used to describe any physical page; this means
 120  * PFN 0 == physical address 0.
 121  *
 122  * This is the PFN of the first RAM page in the kernel
 123  * direct-mapped view.  We assume this is the first page
 124  * of RAM in the mem_map as well.
 125  */
 126 #define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
 127
 128 /*
 129  * Note: Drivers should NOT use these.  They are the wrong
 130  * translation for translating DMA addresses.  Use the driver
 131  * DMA support - see dma-mapping.h.
 132  */
 133 #define virt_to_phys virt_to_phys
 134 static inline phys_addr_t virt_to_phys(const volatile void *x)
 135 {
 136         return __virt_to_phys((unsigned long)(x));
 137 }
 138
 139 #define phys_to_virt phys_to_virt
 140 static inline void *phys_to_virt(phys_addr_t x)
 141 {
 142         return (void *)(__phys_to_virt(x));
 143 }
 144
 145 /*
 146  * Drivers should NOT use these either.
 147  */
 148 #define __pa(x)                 __virt_to_phys((unsigned long)(x))
 149 #define __va(x)                 ((void *)__phys_to_virt((phys_addr_t)(x)))
 150 #define pfn_to_kaddr(pfn)       __va((pfn) << PAGE_SHIFT)
 151 #define virt_to_pfn(x)      __phys_to_pfn(__virt_to_phys(x))
 152
 153 /*
 154  *  virt_to_page(k)     convert a _valid_ virtual address to struct page *
 155  *  virt_addr_valid(k)  indicates whether a virtual address is valid
 156  */
 157 #define ARCH_PFN_OFFSET         ((unsigned long)PHYS_PFN_OFFSET)
 158
 159 #define virt_to_page(kaddr)     pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
 160 #define virt_addr_valid(kaddr)  pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
 161
 162 #endif
 163
 164 #include <asm-generic/memory_model.h>
 165
 166 #endif