Linux kernel mirror (for testing)
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linux
1/*
2 * linux/include/asm-arm/memory.h
3 *
4 * Copyright (C) 2000-2002 Russell King
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * Note: this file should not be included by non-asm/.h files
11 */
12#ifndef __ASM_ARM_MEMORY_H
13#define __ASM_ARM_MEMORY_H
14
15/*
16 * Allow for constants defined here to be used from assembly code
17 * by prepending the UL suffix only with actual C code compilation.
18 */
19#ifndef __ASSEMBLY__
20#define UL(x) (x##UL)
21#else
22#define UL(x) (x)
23#endif
24
25#include <linux/config.h>
26#include <linux/compiler.h>
27#include <asm/arch/memory.h>
28#include <asm/sizes.h>
29
30#ifndef TASK_SIZE
31/*
32 * TASK_SIZE - the maximum size of a user space task.
33 * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area
34 */
35#define TASK_SIZE UL(0xbf000000)
36#define TASK_UNMAPPED_BASE UL(0x40000000)
37#endif
38
39/*
40 * The maximum size of a 26-bit user space task.
41 */
42#define TASK_SIZE_26 UL(0x04000000)
43
44/*
45 * Page offset: 3GB
46 */
47#ifndef PAGE_OFFSET
48#define PAGE_OFFSET UL(0xc0000000)
49#endif
50
51/*
52 * Size of DMA-consistent memory region. Must be multiple of 2M,
53 * between 2MB and 14MB inclusive.
54 */
55#ifndef CONSISTENT_DMA_SIZE
56#define CONSISTENT_DMA_SIZE SZ_2M
57#endif
58
59/*
60 * Physical vs virtual RAM address space conversion. These are
61 * private definitions which should NOT be used outside memory.h
62 * files. Use virt_to_phys/phys_to_virt/__pa/__va instead.
63 */
64#ifndef __virt_to_phys
65#define __virt_to_phys(x) ((x) - PAGE_OFFSET + PHYS_OFFSET)
66#define __phys_to_virt(x) ((x) - PHYS_OFFSET + PAGE_OFFSET)
67#endif
68
69/*
70 * Convert a physical address to a Page Frame Number and back
71 */
72#define __phys_to_pfn(paddr) ((paddr) >> PAGE_SHIFT)
73#define __pfn_to_phys(pfn) ((pfn) << PAGE_SHIFT)
74
75/*
76 * The module space lives between the addresses given by TASK_SIZE
77 * and PAGE_OFFSET - it must be within 32MB of the kernel text.
78 */
79#define MODULE_END (PAGE_OFFSET)
80#define MODULE_START (MODULE_END - 16*1048576)
81
82#if TASK_SIZE > MODULE_START
83#error Top of user space clashes with start of module space
84#endif
85
86/*
87 * The XIP kernel gets mapped at the bottom of the module vm area.
88 * Since we use sections to map it, this macro replaces the physical address
89 * with its virtual address while keeping offset from the base section.
90 */
91#define XIP_VIRT_ADDR(physaddr) (MODULE_START + ((physaddr) & 0x000fffff))
92
93#ifndef __ASSEMBLY__
94
95/*
96 * The DMA mask corresponding to the maximum bus address allocatable
97 * using GFP_DMA. The default here places no restriction on DMA
98 * allocations. This must be the smallest DMA mask in the system,
99 * so a successful GFP_DMA allocation will always satisfy this.
100 */
101#ifndef ISA_DMA_THRESHOLD
102#define ISA_DMA_THRESHOLD (0xffffffffULL)
103#endif
104
105#ifndef arch_adjust_zones
106#define arch_adjust_zones(node,size,holes) do { } while (0)
107#endif
108
109/*
110 * PFNs are used to describe any physical page; this means
111 * PFN 0 == physical address 0.
112 *
113 * This is the PFN of the first RAM page in the kernel
114 * direct-mapped view. We assume this is the first page
115 * of RAM in the mem_map as well.
116 */
117#define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
118
119/*
120 * These are *only* valid on the kernel direct mapped RAM memory.
121 * Note: Drivers should NOT use these. They are the wrong
122 * translation for translating DMA addresses. Use the driver
123 * DMA support - see dma-mapping.h.
124 */
125static inline unsigned long virt_to_phys(void *x)
126{
127 return __virt_to_phys((unsigned long)(x));
128}
129
130static inline void *phys_to_virt(unsigned long x)
131{
132 return (void *)(__phys_to_virt((unsigned long)(x)));
133}
134
135/*
136 * Drivers should NOT use these either.
137 */
138#define __pa(x) __virt_to_phys((unsigned long)(x))
139#define __va(x) ((void *)__phys_to_virt((unsigned long)(x)))
140#define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT)
141
142/*
143 * Virtual <-> DMA view memory address translations
144 * Again, these are *only* valid on the kernel direct mapped RAM
145 * memory. Use of these is *deprecated* (and that doesn't mean
146 * use the __ prefixed forms instead.) See dma-mapping.h.
147 */
148static inline __deprecated unsigned long virt_to_bus(void *x)
149{
150 return __virt_to_bus((unsigned long)x);
151}
152
153static inline __deprecated void *bus_to_virt(unsigned long x)
154{
155 return (void *)__bus_to_virt(x);
156}
157
158/*
159 * Conversion between a struct page and a physical address.
160 *
161 * Note: when converting an unknown physical address to a
162 * struct page, the resulting pointer must be validated
163 * using VALID_PAGE(). It must return an invalid struct page
164 * for any physical address not corresponding to a system
165 * RAM address.
166 *
167 * page_to_pfn(page) convert a struct page * to a PFN number
168 * pfn_to_page(pfn) convert a _valid_ PFN number to struct page *
169 * pfn_valid(pfn) indicates whether a PFN number is valid
170 *
171 * virt_to_page(k) convert a _valid_ virtual address to struct page *
172 * virt_addr_valid(k) indicates whether a virtual address is valid
173 */
174#ifndef CONFIG_DISCONTIGMEM
175
176#define page_to_pfn(page) (((page) - mem_map) + PHYS_PFN_OFFSET)
177#define pfn_to_page(pfn) ((mem_map + (pfn)) - PHYS_PFN_OFFSET)
178#define pfn_valid(pfn) ((pfn) >= PHYS_PFN_OFFSET && (pfn) < (PHYS_PFN_OFFSET + max_mapnr))
179
180#define virt_to_page(kaddr) (pfn_to_page(__pa(kaddr) >> PAGE_SHIFT))
181#define virt_addr_valid(kaddr) ((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory)
182
183#define PHYS_TO_NID(addr) (0)
184
185#else /* CONFIG_DISCONTIGMEM */
186
187/*
188 * This is more complex. We have a set of mem_map arrays spread
189 * around in memory.
190 */
191#include <linux/numa.h>
192
193#define page_to_pfn(page) \
194 (( (page) - page_zone(page)->zone_mem_map) \
195 + page_zone(page)->zone_start_pfn)
196
197#define pfn_to_page(pfn) \
198 (PFN_TO_MAPBASE(pfn) + LOCAL_MAP_NR((pfn) << PAGE_SHIFT))
199
200#define pfn_valid(pfn) \
201 ({ \
202 unsigned int nid = PFN_TO_NID(pfn); \
203 int valid = nid < MAX_NUMNODES; \
204 if (valid) { \
205 pg_data_t *node = NODE_DATA(nid); \
206 valid = (pfn - node->node_start_pfn) < \
207 node->node_spanned_pages; \
208 } \
209 valid; \
210 })
211
212#define virt_to_page(kaddr) \
213 (ADDR_TO_MAPBASE(kaddr) + LOCAL_MAP_NR(kaddr))
214
215#define virt_addr_valid(kaddr) (KVADDR_TO_NID(kaddr) < MAX_NUMNODES)
216
217/*
218 * Common discontigmem stuff.
219 * PHYS_TO_NID is used by the ARM kernel/setup.c
220 */
221#define PHYS_TO_NID(addr) PFN_TO_NID((addr) >> PAGE_SHIFT)
222
223#endif /* !CONFIG_DISCONTIGMEM */
224
225/*
226 * For BIO. "will die". Kill me when bio_to_phys() and bvec_to_phys() die.
227 */
228#define page_to_phys(page) (page_to_pfn(page) << PAGE_SHIFT)
229
230/*
231 * Optional device DMA address remapping. Do _not_ use directly!
232 * We should really eliminate virt_to_bus() here - it's deprecated.
233 */
234#ifndef __arch_page_to_dma
235#define page_to_dma(dev, page) ((dma_addr_t)__virt_to_bus((unsigned long)page_address(page)))
236#define dma_to_virt(dev, addr) ((void *)__bus_to_virt(addr))
237#define virt_to_dma(dev, addr) ((dma_addr_t)__virt_to_bus((unsigned long)(addr)))
238#else
239#define page_to_dma(dev, page) (__arch_page_to_dma(dev, page))
240#define dma_to_virt(dev, addr) (__arch_dma_to_virt(dev, addr))
241#define virt_to_dma(dev, addr) (__arch_virt_to_dma(dev, addr))
242#endif
243
244#endif
245
246#endif