xref: /linux/arch/arm/include/asm/memory.h (revision 98b8788ae91694499d1995035625bea16a4db0c4)
1 /*
2  *  arch/arm/include/asm/memory.h
3  *
4  *  Copyright (C) 2000-2002 Russell King
5  *  modification for nommu, Hyok S. Choi, 2004
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  *  Note: this file should not be included by non-asm/.h files
12  */
13 #ifndef __ASM_ARM_MEMORY_H
14 #define __ASM_ARM_MEMORY_H
15 
16 #include <linux/compiler.h>
17 #include <linux/const.h>
18 #include <mach/memory.h>
19 #include <asm/sizes.h>
20 
21 /*
22  * Allow for constants defined here to be used from assembly code
23  * by prepending the UL suffix only with actual C code compilation.
24  */
25 #define UL(x) _AC(x, UL)
26 
27 #ifdef CONFIG_MMU
28 
29 /*
30  * PAGE_OFFSET - the virtual address of the start of the kernel image
31  * TASK_SIZE - the maximum size of a user space task.
32  * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area
33  */
34 #define PAGE_OFFSET		UL(CONFIG_PAGE_OFFSET)
35 #define TASK_SIZE		(UL(CONFIG_PAGE_OFFSET) - UL(0x01000000))
36 #define TASK_UNMAPPED_BASE	(UL(CONFIG_PAGE_OFFSET) / 3)
37 
38 /*
39  * The maximum size of a 26-bit user space task.
40  */
41 #define TASK_SIZE_26		UL(0x04000000)
42 
43 /*
44  * The module space lives between the addresses given by TASK_SIZE
45  * and PAGE_OFFSET - it must be within 32MB of the kernel text.
46  */
47 #ifndef CONFIG_THUMB2_KERNEL
48 #define MODULES_VADDR		(PAGE_OFFSET - 16*1024*1024)
49 #else
50 /* smaller range for Thumb-2 symbols relocation (2^24)*/
51 #define MODULES_VADDR		(PAGE_OFFSET - 8*1024*1024)
52 #endif
53 
54 #if TASK_SIZE > MODULES_VADDR
55 #error Top of user space clashes with start of module space
56 #endif
57 
58 /*
59  * The highmem pkmap virtual space shares the end of the module area.
60  */
61 #ifdef CONFIG_HIGHMEM
62 #define MODULES_END		(PAGE_OFFSET - PMD_SIZE)
63 #else
64 #define MODULES_END		(PAGE_OFFSET)
65 #endif
66 
67 /*
68  * The XIP kernel gets mapped at the bottom of the module vm area.
69  * Since we use sections to map it, this macro replaces the physical address
70  * with its virtual address while keeping offset from the base section.
71  */
72 #define XIP_VIRT_ADDR(physaddr)  (MODULES_VADDR + ((physaddr) & 0x000fffff))
73 
74 /*
75  * Allow 16MB-aligned ioremap pages
76  */
77 #define IOREMAP_MAX_ORDER	24
78 
79 #else /* CONFIG_MMU */
80 
81 /*
82  * The limitation of user task size can grow up to the end of free ram region.
83  * It is difficult to define and perhaps will never meet the original meaning
84  * of this define that was meant to.
85  * Fortunately, there is no reference for this in noMMU mode, for now.
86  */
87 #ifndef TASK_SIZE
88 #define TASK_SIZE		(CONFIG_DRAM_SIZE)
89 #endif
90 
91 #ifndef TASK_UNMAPPED_BASE
92 #define TASK_UNMAPPED_BASE	UL(0x00000000)
93 #endif
94 
95 #ifndef PHYS_OFFSET
96 #define PHYS_OFFSET 		(CONFIG_DRAM_BASE)
97 #endif
98 
99 #ifndef END_MEM
100 #define END_MEM     		(CONFIG_DRAM_BASE + CONFIG_DRAM_SIZE)
101 #endif
102 
103 #ifndef PAGE_OFFSET
104 #define PAGE_OFFSET		(PHYS_OFFSET)
105 #endif
106 
107 /*
108  * The module can be at any place in ram in nommu mode.
109  */
110 #define MODULES_END		(END_MEM)
111 #define MODULES_VADDR		(PHYS_OFFSET)
112 
113 #endif /* !CONFIG_MMU */
114 
115 /*
116  * Size of DMA-consistent memory region.  Must be multiple of 2M,
117  * between 2MB and 14MB inclusive.
118  */
119 #ifndef CONSISTENT_DMA_SIZE
120 #define CONSISTENT_DMA_SIZE SZ_2M
121 #endif
122 
123 /*
124  * Physical vs virtual RAM address space conversion.  These are
125  * private definitions which should NOT be used outside memory.h
126  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
127  */
128 #ifndef __virt_to_phys
129 #define __virt_to_phys(x)	((x) - PAGE_OFFSET + PHYS_OFFSET)
130 #define __phys_to_virt(x)	((x) - PHYS_OFFSET + PAGE_OFFSET)
131 #endif
132 
133 /*
134  * Convert a physical address to a Page Frame Number and back
135  */
136 #define	__phys_to_pfn(paddr)	((paddr) >> PAGE_SHIFT)
137 #define	__pfn_to_phys(pfn)	((pfn) << PAGE_SHIFT)
138 
139 /*
140  * Convert a page to/from a physical address
141  */
142 #define page_to_phys(page)	(__pfn_to_phys(page_to_pfn(page)))
143 #define phys_to_page(phys)	(pfn_to_page(__phys_to_pfn(phys)))
144 
145 #ifndef __ASSEMBLY__
146 
147 /*
148  * The DMA mask corresponding to the maximum bus address allocatable
149  * using GFP_DMA.  The default here places no restriction on DMA
150  * allocations.  This must be the smallest DMA mask in the system,
151  * so a successful GFP_DMA allocation will always satisfy this.
152  */
153 #ifndef ISA_DMA_THRESHOLD
154 #define ISA_DMA_THRESHOLD	(0xffffffffULL)
155 #endif
156 
157 #ifndef arch_adjust_zones
158 #define arch_adjust_zones(node,size,holes) do { } while (0)
159 #elif !defined(CONFIG_ZONE_DMA)
160 #error "custom arch_adjust_zones() requires CONFIG_ZONE_DMA"
161 #endif
162 
163 /*
164  * PFNs are used to describe any physical page; this means
165  * PFN 0 == physical address 0.
166  *
167  * This is the PFN of the first RAM page in the kernel
168  * direct-mapped view.  We assume this is the first page
169  * of RAM in the mem_map as well.
170  */
171 #define PHYS_PFN_OFFSET	(PHYS_OFFSET >> PAGE_SHIFT)
172 
173 /*
174  * These are *only* valid on the kernel direct mapped RAM memory.
175  * Note: Drivers should NOT use these.  They are the wrong
176  * translation for translating DMA addresses.  Use the driver
177  * DMA support - see dma-mapping.h.
178  */
179 static inline unsigned long virt_to_phys(void *x)
180 {
181 	return __virt_to_phys((unsigned long)(x));
182 }
183 
184 static inline void *phys_to_virt(unsigned long x)
185 {
186 	return (void *)(__phys_to_virt((unsigned long)(x)));
187 }
188 
189 /*
190  * Drivers should NOT use these either.
191  */
192 #define __pa(x)			__virt_to_phys((unsigned long)(x))
193 #define __va(x)			((void *)__phys_to_virt((unsigned long)(x)))
194 #define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
195 
196 /*
197  * Virtual <-> DMA view memory address translations
198  * Again, these are *only* valid on the kernel direct mapped RAM
199  * memory.  Use of these is *deprecated* (and that doesn't mean
200  * use the __ prefixed forms instead.)  See dma-mapping.h.
201  */
202 #ifndef __virt_to_bus
203 #define __virt_to_bus	__virt_to_phys
204 #define __bus_to_virt	__phys_to_virt
205 #define __pfn_to_bus(x)	__pfn_to_phys(x)
206 #define __bus_to_pfn(x)	__phys_to_pfn(x)
207 #endif
208 
209 static inline __deprecated unsigned long virt_to_bus(void *x)
210 {
211 	return __virt_to_bus((unsigned long)x);
212 }
213 
214 static inline __deprecated void *bus_to_virt(unsigned long x)
215 {
216 	return (void *)__bus_to_virt(x);
217 }
218 
219 /*
220  * Conversion between a struct page and a physical address.
221  *
222  * Note: when converting an unknown physical address to a
223  * struct page, the resulting pointer must be validated
224  * using VALID_PAGE().  It must return an invalid struct page
225  * for any physical address not corresponding to a system
226  * RAM address.
227  *
228  *  page_to_pfn(page)	convert a struct page * to a PFN number
229  *  pfn_to_page(pfn)	convert a _valid_ PFN number to struct page *
230  *
231  *  virt_to_page(k)	convert a _valid_ virtual address to struct page *
232  *  virt_addr_valid(k)	indicates whether a virtual address is valid
233  */
234 #ifndef CONFIG_DISCONTIGMEM
235 
236 #define ARCH_PFN_OFFSET		PHYS_PFN_OFFSET
237 
238 #define virt_to_page(kaddr)	pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
239 #define virt_addr_valid(kaddr)	((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory)
240 
241 #define PHYS_TO_NID(addr)	(0)
242 
243 #else /* CONFIG_DISCONTIGMEM */
244 
245 /*
246  * This is more complex.  We have a set of mem_map arrays spread
247  * around in memory.
248  */
249 #include <linux/numa.h>
250 
251 #define arch_pfn_to_nid(pfn)	PFN_TO_NID(pfn)
252 #define arch_local_page_offset(pfn, nid) LOCAL_MAP_NR((pfn) << PAGE_SHIFT)
253 
254 #define virt_to_page(kaddr)					\
255 	(ADDR_TO_MAPBASE(kaddr) + LOCAL_MAP_NR(kaddr))
256 
257 #define virt_addr_valid(kaddr)	(KVADDR_TO_NID(kaddr) < MAX_NUMNODES)
258 
259 /*
260  * Common discontigmem stuff.
261  *  PHYS_TO_NID is used by the ARM kernel/setup.c
262  */
263 #define PHYS_TO_NID(addr)	PFN_TO_NID((addr) >> PAGE_SHIFT)
264 
265 /*
266  * Given a kaddr, ADDR_TO_MAPBASE finds the owning node of the memory
267  * and returns the mem_map of that node.
268  */
269 #define ADDR_TO_MAPBASE(kaddr)	NODE_MEM_MAP(KVADDR_TO_NID(kaddr))
270 
271 /*
272  * Given a page frame number, find the owning node of the memory
273  * and returns the mem_map of that node.
274  */
275 #define PFN_TO_MAPBASE(pfn)	NODE_MEM_MAP(PFN_TO_NID(pfn))
276 
277 #ifdef NODE_MEM_SIZE_BITS
278 #define NODE_MEM_SIZE_MASK	((1 << NODE_MEM_SIZE_BITS) - 1)
279 
280 /*
281  * Given a kernel address, find the home node of the underlying memory.
282  */
283 #define KVADDR_TO_NID(addr) \
284 	(((unsigned long)(addr) - PAGE_OFFSET) >> NODE_MEM_SIZE_BITS)
285 
286 /*
287  * Given a page frame number, convert it to a node id.
288  */
289 #define PFN_TO_NID(pfn) \
290 	(((pfn) - PHYS_PFN_OFFSET) >> (NODE_MEM_SIZE_BITS - PAGE_SHIFT))
291 
292 /*
293  * Given a kaddr, LOCAL_MEM_MAP finds the owning node of the memory
294  * and returns the index corresponding to the appropriate page in the
295  * node's mem_map.
296  */
297 #define LOCAL_MAP_NR(addr) \
298 	(((unsigned long)(addr) & NODE_MEM_SIZE_MASK) >> PAGE_SHIFT)
299 
300 #endif /* NODE_MEM_SIZE_BITS */
301 
302 #endif /* !CONFIG_DISCONTIGMEM */
303 
304 /*
305  * Optional coherency support.  Currently used only by selected
306  * Intel XSC3-based systems.
307  */
308 #ifndef arch_is_coherent
309 #define arch_is_coherent()		0
310 #endif
311 
312 #endif
313 
314 #include <asm-generic/memory_model.h>
315 
316 #endif
317