2 * Based on arch/arm/include/asm/memory.h
4 * Copyright (C) 2000-2002 Russell King
5 * Copyright (C) 2012 ARM Ltd.
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.
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.
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/>.
19 * Note: this file should not be included by non-asm/.h files
21 #ifndef __ASM_MEMORY_H
22 #define __ASM_MEMORY_H
24 #include <linux/compiler.h>
25 #include <linux/const.h>
26 #include <linux/types.h>
27 #include <asm/sizes.h>
30 * Allow for constants defined here to be used from assembly code
31 * by prepending the UL suffix only with actual C code compilation.
33 #define UL(x) _AC(x, UL)
36 * PAGE_OFFSET - the virtual address of the start of the kernel image (top
38 * VA_BITS - the maximum number of bits for virtual addresses.
39 * TASK_SIZE - the maximum size of a user space task.
40 * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area.
41 * The module space lives between the addresses given by TASK_SIZE
42 * and PAGE_OFFSET - it must be within 128MB of the kernel text.
44 #ifdef CONFIG_ARM64_64K_PAGES
49 #define PAGE_OFFSET (UL(0xffffffffffffffff) << (VA_BITS - 1))
50 #define MODULES_END (PAGE_OFFSET)
51 #define MODULES_VADDR (MODULES_END - SZ_64M)
52 #define FIXADDR_TOP (MODULES_VADDR - SZ_2M - PAGE_SIZE)
53 #define TASK_SIZE_64 (UL(1) << VA_BITS)
56 #define TASK_SIZE_32 UL(0x100000000)
57 #define TASK_SIZE (test_thread_flag(TIF_32BIT) ? \
58 TASK_SIZE_32 : TASK_SIZE_64)
59 #define TASK_SIZE_OF(tsk) (test_tsk_thread_flag(tsk, TIF_32BIT) ? \
60 TASK_SIZE_32 : TASK_SIZE_64)
62 #define TASK_SIZE TASK_SIZE_64
63 #endif /* CONFIG_COMPAT */
65 #define TASK_UNMAPPED_BASE (PAGE_ALIGN(TASK_SIZE / 4))
67 #if TASK_SIZE_64 > MODULES_VADDR
68 #error Top of 64-bit user space clashes with start of module space
72 * Physical vs virtual RAM address space conversion. These are
73 * private definitions which should NOT be used outside memory.h
74 * files. Use virt_to_phys/phys_to_virt/__pa/__va instead.
76 #define __virt_to_phys(x) (((phys_addr_t)(x) - PAGE_OFFSET + PHYS_OFFSET))
77 #define __phys_to_virt(x) ((unsigned long)((x) - PHYS_OFFSET + PAGE_OFFSET))
80 * Convert a physical address to a Page Frame Number and back
82 #define __phys_to_pfn(paddr) ((unsigned long)((paddr) >> PAGE_SHIFT))
83 #define __pfn_to_phys(pfn) ((phys_addr_t)(pfn) << PAGE_SHIFT)
86 * Convert a page to/from a physical address
88 #define page_to_phys(page) (__pfn_to_phys(page_to_pfn(page)))
89 #define phys_to_page(phys) (pfn_to_page(__phys_to_pfn(phys)))
92 * Memory types available.
94 #define MT_DEVICE_nGnRnE 0
95 #define MT_DEVICE_nGnRE 1
96 #define MT_DEVICE_GRE 2
97 #define MT_NORMAL_NC 3
101 * Memory types for Stage-2 translation
103 #define MT_S2_NORMAL 0xf
104 #define MT_S2_DEVICE_nGnRE 0x1
108 extern phys_addr_t memstart_addr;
109 /* PHYS_OFFSET - the physical address of the start of memory. */
110 #define PHYS_OFFSET ({ memstart_addr; })
113 * PFNs are used to describe any physical page; this means
114 * PFN 0 == physical address 0.
116 * This is the PFN of the first RAM page in the kernel
117 * direct-mapped view. We assume this is the first page
118 * of RAM in the mem_map as well.
120 #define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
123 * Note: Drivers should NOT use these. They are the wrong
124 * translation for translating DMA addresses. Use the driver
125 * DMA support - see dma-mapping.h.
127 static inline phys_addr_t virt_to_phys(const volatile void *x)
129 return __virt_to_phys((unsigned long)(x));
132 static inline void *phys_to_virt(phys_addr_t x)
134 return (void *)(__phys_to_virt(x));
138 * Drivers should NOT use these either.
140 #define __pa(x) __virt_to_phys((unsigned long)(x))
141 #define __va(x) ((void *)__phys_to_virt((phys_addr_t)(x)))
142 #define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT)
143 #define virt_to_pfn(x) __phys_to_pfn(__virt_to_phys(x))
146 * virt_to_page(k) convert a _valid_ virtual address to struct page *
147 * virt_addr_valid(k) indicates whether a virtual address is valid
149 #define ARCH_PFN_OFFSET PHYS_PFN_OFFSET
151 #define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
152 #define virt_addr_valid(kaddr) (((void *)(kaddr) >= (void *)PAGE_OFFSET) && \
153 ((void *)(kaddr) < (void *)high_memory))
157 #include <asm-generic/memory_model.h>