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 #ifndef __ASSEMBLY__ 94 95 extern phys_addr_t memstart_addr; 96 /* PHYS_OFFSET - the physical address of the start of memory. */ 97 #define PHYS_OFFSET ({ memstart_addr; }) 98 99 /* 100 * PFNs are used to describe any physical page; this means 101 * PFN 0 == physical address 0. 102 * 103 * This is the PFN of the first RAM page in the kernel 104 * direct-mapped view. We assume this is the first page 105 * of RAM in the mem_map as well. 106 */ 107 #define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT) 108 109 /* 110 * Note: Drivers should NOT use these. They are the wrong 111 * translation for translating DMA addresses. Use the driver 112 * DMA support - see dma-mapping.h. 113 */ 114 static inline phys_addr_t virt_to_phys(const volatile void *x) 115 { 116 return __virt_to_phys((unsigned long)(x)); 117 } 118 119 static inline void *phys_to_virt(phys_addr_t x) 120 { 121 return (void *)(__phys_to_virt(x)); 122 } 123 124 /* 125 * Drivers should NOT use these either. 126 */ 127 #define __pa(x) __virt_to_phys((unsigned long)(x)) 128 #define __va(x) ((void *)__phys_to_virt((phys_addr_t)(x))) 129 #define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT) 130 131 /* 132 * virt_to_page(k) convert a _valid_ virtual address to struct page * 133 * virt_addr_valid(k) indicates whether a virtual address is valid 134 */ 135 #define ARCH_PFN_OFFSET PHYS_PFN_OFFSET 136 137 #define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT) 138 #define virt_addr_valid(kaddr) (((void *)(kaddr) >= (void *)PAGE_OFFSET) && \ 139 ((void *)(kaddr) < (void *)high_memory)) 140 141 #endif 142 143 #include <asm-generic/memory_model.h> 144 145 #endif 146