2 * linux/include/asm-arm/memory.h
4 * Copyright (C) 2000-2002 Russell King
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.
10 * Note: this file should not be included by non-asm/.h files
12 #ifndef __ASM_ARM_MEMORY_H
13 #define __ASM_ARM_MEMORY_H
16 * Allow for constants defined here to be used from assembly code
17 * by prepending the UL suffix only with actual C code compilation.
25 #include <linux/compiler.h>
26 #include <asm/arch/memory.h>
27 #include <asm/sizes.h>
31 * TASK_SIZE - the maximum size of a user space task.
32 * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area
34 #define TASK_SIZE UL(0xbf000000)
35 #define TASK_UNMAPPED_BASE UL(0x40000000)
39 * The maximum size of a 26-bit user space task.
41 #define TASK_SIZE_26 UL(0x04000000)
47 #define PAGE_OFFSET UL(0xc0000000)
51 * Size of DMA-consistent memory region. Must be multiple of 2M,
52 * between 2MB and 14MB inclusive.
54 #ifndef CONSISTENT_DMA_SIZE
55 #define CONSISTENT_DMA_SIZE SZ_2M
59 * Physical vs virtual RAM address space conversion. These are
60 * private definitions which should NOT be used outside memory.h
61 * files. Use virt_to_phys/phys_to_virt/__pa/__va instead.
63 #ifndef __virt_to_phys
64 #define __virt_to_phys(x) ((x) - PAGE_OFFSET + PHYS_OFFSET)
65 #define __phys_to_virt(x) ((x) - PHYS_OFFSET + PAGE_OFFSET)
69 * Convert a physical address to a Page Frame Number and back
71 #define __phys_to_pfn(paddr) ((paddr) >> PAGE_SHIFT)
72 #define __pfn_to_phys(pfn) ((pfn) << PAGE_SHIFT)
75 * The module space lives between the addresses given by TASK_SIZE
76 * and PAGE_OFFSET - it must be within 32MB of the kernel text.
78 #define MODULE_END (PAGE_OFFSET)
79 #define MODULE_START (MODULE_END - 16*1048576)
81 #if TASK_SIZE > MODULE_START
82 #error Top of user space clashes with start of module space
86 * The XIP kernel gets mapped at the bottom of the module vm area.
87 * Since we use sections to map it, this macro replaces the physical address
88 * with its virtual address while keeping offset from the base section.
90 #define XIP_VIRT_ADDR(physaddr) (MODULE_START + ((physaddr) & 0x000fffff))
95 * The DMA mask corresponding to the maximum bus address allocatable
96 * using GFP_DMA. The default here places no restriction on DMA
97 * allocations. This must be the smallest DMA mask in the system,
98 * so a successful GFP_DMA allocation will always satisfy this.
100 #ifndef ISA_DMA_THRESHOLD
101 #define ISA_DMA_THRESHOLD (0xffffffffULL)
104 #ifndef arch_adjust_zones
105 #define arch_adjust_zones(node,size,holes) do { } while (0)
109 * PFNs are used to describe any physical page; this means
110 * PFN 0 == physical address 0.
112 * This is the PFN of the first RAM page in the kernel
113 * direct-mapped view. We assume this is the first page
114 * of RAM in the mem_map as well.
116 #define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
119 * These are *only* valid on the kernel direct mapped RAM memory.
120 * Note: Drivers should NOT use these. They are the wrong
121 * translation for translating DMA addresses. Use the driver
122 * DMA support - see dma-mapping.h.
124 static inline unsigned long virt_to_phys(void *x)
126 return __virt_to_phys((unsigned long)(x));
129 static inline void *phys_to_virt(unsigned long x)
131 return (void *)(__phys_to_virt((unsigned long)(x)));
135 * Drivers should NOT use these either.
137 #define __pa(x) __virt_to_phys((unsigned long)(x))
138 #define __va(x) ((void *)__phys_to_virt((unsigned long)(x)))
139 #define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT)
142 * Virtual <-> DMA view memory address translations
143 * Again, these are *only* valid on the kernel direct mapped RAM
144 * memory. Use of these is *deprecated* (and that doesn't mean
145 * use the __ prefixed forms instead.) See dma-mapping.h.
147 static inline __deprecated unsigned long virt_to_bus(void *x)
149 return __virt_to_bus((unsigned long)x);
152 static inline __deprecated void *bus_to_virt(unsigned long x)
154 return (void *)__bus_to_virt(x);
158 * Conversion between a struct page and a physical address.
160 * Note: when converting an unknown physical address to a
161 * struct page, the resulting pointer must be validated
162 * using VALID_PAGE(). It must return an invalid struct page
163 * for any physical address not corresponding to a system
166 * page_to_pfn(page) convert a struct page * to a PFN number
167 * pfn_to_page(pfn) convert a _valid_ PFN number to struct page *
168 * pfn_valid(pfn) indicates whether a PFN number is valid
170 * virt_to_page(k) convert a _valid_ virtual address to struct page *
171 * virt_addr_valid(k) indicates whether a virtual address is valid
173 #ifndef CONFIG_DISCONTIGMEM
174 #define ARCH_PFN_OFFSET PHYS_PFN_OFFSET
175 #define pfn_valid(pfn) ((pfn) >= PHYS_PFN_OFFSET && (pfn) < (PHYS_PFN_OFFSET + max_mapnr))
177 #define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
178 #define virt_addr_valid(kaddr) ((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory)
180 #define PHYS_TO_NID(addr) (0)
182 #else /* CONFIG_DISCONTIGMEM */
185 * This is more complex. We have a set of mem_map arrays spread
188 #include <linux/numa.h>
189 #define arch_pfn_to_nid(pfn) PFN_TO_NID(pfn)
190 #define arch_local_page_offset(pfn, nid) LOCAL_MAP_NR((pfn) << PAGE_SHIFT)
192 #define pfn_valid(pfn) \
194 unsigned int nid = PFN_TO_NID(pfn); \
195 int valid = nid < MAX_NUMNODES; \
197 pg_data_t *node = NODE_DATA(nid); \
198 valid = (pfn - node->node_start_pfn) < \
199 node->node_spanned_pages; \
204 #define virt_to_page(kaddr) \
205 (ADDR_TO_MAPBASE(kaddr) + LOCAL_MAP_NR(kaddr))
207 #define virt_addr_valid(kaddr) (KVADDR_TO_NID(kaddr) < MAX_NUMNODES)
210 * Common discontigmem stuff.
211 * PHYS_TO_NID is used by the ARM kernel/setup.c
213 #define PHYS_TO_NID(addr) PFN_TO_NID((addr) >> PAGE_SHIFT)
215 #endif /* !CONFIG_DISCONTIGMEM */
218 * For BIO. "will die". Kill me when bio_to_phys() and bvec_to_phys() die.
220 #define page_to_phys(page) (page_to_pfn(page) << PAGE_SHIFT)
223 * Optional device DMA address remapping. Do _not_ use directly!
224 * We should really eliminate virt_to_bus() here - it's deprecated.
226 #ifndef __arch_page_to_dma
227 #define page_to_dma(dev, page) ((dma_addr_t)__virt_to_bus((unsigned long)page_address(page)))
228 #define dma_to_virt(dev, addr) ((void *)__bus_to_virt(addr))
229 #define virt_to_dma(dev, addr) ((dma_addr_t)__virt_to_bus((unsigned long)(addr)))
231 #define page_to_dma(dev, page) (__arch_page_to_dma(dev, page))
232 #define dma_to_virt(dev, addr) (__arch_dma_to_virt(dev, addr))
233 #define virt_to_dma(dev, addr) (__arch_virt_to_dma(dev, addr))
237 * Optional coherency support. Currently used only by selected
238 * Intel XSC3-based systems.
240 #ifndef arch_is_coherent
241 #define arch_is_coherent() 0
246 #include <asm-generic/memory_model.h>