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 145