Linux kernel mirror (for testing)
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linux
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 (top
37 * (VA_BITS - 1))
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.
43 */
44#ifdef CONFIG_ARM64_64K_PAGES
45#define VA_BITS (42)
46#else
47#define VA_BITS (39)
48#endif
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)
54
55#ifdef CONFIG_COMPAT
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)
61#else
62#define TASK_SIZE TASK_SIZE_64
63#endif /* CONFIG_COMPAT */
64
65#define TASK_UNMAPPED_BASE (PAGE_ALIGN(TASK_SIZE / 4))
66
67#if TASK_SIZE_64 > MODULES_VADDR
68#error Top of 64-bit user space clashes with start of module space
69#endif
70
71/*
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.
75 */
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))
78
79/*
80 * Convert a physical address to a Page Frame Number and back
81 */
82#define __phys_to_pfn(paddr) ((unsigned long)((paddr) >> PAGE_SHIFT))
83#define __pfn_to_phys(pfn) ((phys_addr_t)(pfn) << PAGE_SHIFT)
84
85/*
86 * Convert a page to/from a physical address
87 */
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)))
90
91/*
92 * Memory types available.
93 */
94#define MT_DEVICE_nGnRnE 0
95#define MT_DEVICE_nGnRE 1
96#define MT_DEVICE_GRE 2
97#define MT_NORMAL_NC 3
98#define MT_NORMAL 4
99
100/*
101 * Memory types for Stage-2 translation
102 */
103#define MT_S2_NORMAL 0xf
104#define MT_S2_DEVICE_nGnRE 0x1
105
106#ifndef __ASSEMBLY__
107
108extern phys_addr_t memstart_addr;
109/* PHYS_OFFSET - the physical address of the start of memory. */
110#define PHYS_OFFSET ({ memstart_addr; })
111
112/*
113 * PFNs are used to describe any physical page; this means
114 * PFN 0 == physical address 0.
115 *
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.
119 */
120#define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
121
122/*
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.
126 */
127static inline phys_addr_t virt_to_phys(const volatile void *x)
128{
129 return __virt_to_phys((unsigned long)(x));
130}
131
132static inline void *phys_to_virt(phys_addr_t x)
133{
134 return (void *)(__phys_to_virt(x));
135}
136
137/*
138 * Drivers should NOT use these either.
139 */
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))
144
145/*
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
148 */
149#define ARCH_PFN_OFFSET PHYS_PFN_OFFSET
150
151#define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
152#define virt_addr_valid(kaddr) pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
153
154#endif
155
156#include <asm-generic/memory_model.h>
157
158#endif