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Linux kernel mirror (for testing)
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linux
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 <linux/types.h>
19#include <linux/sizes.h>
20
21#include <asm/cache.h>
22
23#ifdef CONFIG_NEED_MACH_MEMORY_H
24#include <mach/memory.h>
25#endif
26
27/*
28 * Allow for constants defined here to be used from assembly code
29 * by prepending the UL suffix only with actual C code compilation.
30 */
31#define UL(x) _AC(x, UL)
32
33#ifdef CONFIG_MMU
34
35/*
36 * PAGE_OFFSET - the virtual address of the start of the kernel image
37 * TASK_SIZE - the maximum size of a user space task.
38 * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area
39 */
40#define PAGE_OFFSET UL(CONFIG_PAGE_OFFSET)
41#define TASK_SIZE (UL(CONFIG_PAGE_OFFSET) - UL(SZ_16M))
42#define TASK_UNMAPPED_BASE ALIGN(TASK_SIZE / 3, SZ_16M)
43
44/*
45 * The maximum size of a 26-bit user space task.
46 */
47#define TASK_SIZE_26 (UL(1) << 26)
48
49/*
50 * The module space lives between the addresses given by TASK_SIZE
51 * and PAGE_OFFSET - it must be within 32MB of the kernel text.
52 */
53#ifndef CONFIG_THUMB2_KERNEL
54#define MODULES_VADDR (PAGE_OFFSET - SZ_16M)
55#else
56/* smaller range for Thumb-2 symbols relocation (2^24)*/
57#define MODULES_VADDR (PAGE_OFFSET - SZ_8M)
58#endif
59
60#if TASK_SIZE > MODULES_VADDR
61#error Top of user space clashes with start of module space
62#endif
63
64/*
65 * The highmem pkmap virtual space shares the end of the module area.
66 */
67#ifdef CONFIG_HIGHMEM
68#define MODULES_END (PAGE_OFFSET - PMD_SIZE)
69#else
70#define MODULES_END (PAGE_OFFSET)
71#endif
72
73/*
74 * The XIP kernel gets mapped at the bottom of the module vm area.
75 * Since we use sections to map it, this macro replaces the physical address
76 * with its virtual address while keeping offset from the base section.
77 */
78#define XIP_VIRT_ADDR(physaddr) (MODULES_VADDR + ((physaddr) & 0x000fffff))
79
80/*
81 * Allow 16MB-aligned ioremap pages
82 */
83#define IOREMAP_MAX_ORDER 24
84
85#define CONSISTENT_END (0xffe00000UL)
86
87#else /* CONFIG_MMU */
88
89/*
90 * The limitation of user task size can grow up to the end of free ram region.
91 * It is difficult to define and perhaps will never meet the original meaning
92 * of this define that was meant to.
93 * Fortunately, there is no reference for this in noMMU mode, for now.
94 */
95#ifndef TASK_SIZE
96#define TASK_SIZE (CONFIG_DRAM_SIZE)
97#endif
98
99#ifndef TASK_UNMAPPED_BASE
100#define TASK_UNMAPPED_BASE UL(0x00000000)
101#endif
102
103#ifndef PHYS_OFFSET
104#define PHYS_OFFSET UL(CONFIG_DRAM_BASE)
105#endif
106
107#ifndef END_MEM
108#define END_MEM (UL(CONFIG_DRAM_BASE) + CONFIG_DRAM_SIZE)
109#endif
110
111#ifndef PAGE_OFFSET
112#define PAGE_OFFSET (PHYS_OFFSET)
113#endif
114
115/*
116 * The module can be at any place in ram in nommu mode.
117 */
118#define MODULES_END (END_MEM)
119#define MODULES_VADDR (PHYS_OFFSET)
120
121#define XIP_VIRT_ADDR(physaddr) (physaddr)
122
123#endif /* !CONFIG_MMU */
124
125/*
126 * We fix the TCM memories max 32 KiB ITCM resp DTCM at these
127 * locations
128 */
129#ifdef CONFIG_HAVE_TCM
130#define ITCM_OFFSET UL(0xfffe0000)
131#define DTCM_OFFSET UL(0xfffe8000)
132#endif
133
134/*
135 * Convert a physical address to a Page Frame Number and back
136 */
137#define __phys_to_pfn(paddr) ((unsigned long)((paddr) >> PAGE_SHIFT))
138#define __pfn_to_phys(pfn) ((phys_addr_t)(pfn) << PAGE_SHIFT)
139
140/*
141 * Convert a page to/from a physical address
142 */
143#define page_to_phys(page) (__pfn_to_phys(page_to_pfn(page)))
144#define phys_to_page(phys) (pfn_to_page(__phys_to_pfn(phys)))
145
146/*
147 * Minimum guaranted alignment in pgd_alloc(). The page table pointers passed
148 * around in head.S and proc-*.S are shifted by this amount, in order to
149 * leave spare high bits for systems with physical address extension. This
150 * does not fully accomodate the 40-bit addressing capability of ARM LPAE, but
151 * gives us about 38-bits or so.
152 */
153#ifdef CONFIG_ARM_LPAE
154#define ARCH_PGD_SHIFT L1_CACHE_SHIFT
155#else
156#define ARCH_PGD_SHIFT 0
157#endif
158#define ARCH_PGD_MASK ((1 << ARCH_PGD_SHIFT) - 1)
159
160#ifndef __ASSEMBLY__
161
162/*
163 * Physical vs virtual RAM address space conversion. These are
164 * private definitions which should NOT be used outside memory.h
165 * files. Use virt_to_phys/phys_to_virt/__pa/__va instead.
166 */
167#ifndef __virt_to_phys
168#ifdef CONFIG_ARM_PATCH_PHYS_VIRT
169
170/*
171 * Constants used to force the right instruction encodings and shifts
172 * so that all we need to do is modify the 8-bit constant field.
173 */
174#define __PV_BITS_31_24 0x81000000
175
176extern unsigned long __pv_phys_offset;
177#define PHYS_OFFSET __pv_phys_offset
178
179#define __pv_stub(from,to,instr,type) \
180 __asm__("@ __pv_stub\n" \
181 "1: " instr " %0, %1, %2\n" \
182 " .pushsection .pv_table,\"a\"\n" \
183 " .long 1b\n" \
184 " .popsection\n" \
185 : "=r" (to) \
186 : "r" (from), "I" (type))
187
188static inline unsigned long __virt_to_phys(unsigned long x)
189{
190 unsigned long t;
191 __pv_stub(x, t, "add", __PV_BITS_31_24);
192 return t;
193}
194
195static inline unsigned long __phys_to_virt(unsigned long x)
196{
197 unsigned long t;
198 __pv_stub(x, t, "sub", __PV_BITS_31_24);
199 return t;
200}
201#else
202#define __virt_to_phys(x) ((x) - PAGE_OFFSET + PHYS_OFFSET)
203#define __phys_to_virt(x) ((x) - PHYS_OFFSET + PAGE_OFFSET)
204#endif
205#endif
206#endif /* __ASSEMBLY__ */
207
208#ifndef PHYS_OFFSET
209#ifdef PLAT_PHYS_OFFSET
210#define PHYS_OFFSET PLAT_PHYS_OFFSET
211#else
212#define PHYS_OFFSET UL(CONFIG_PHYS_OFFSET)
213#endif
214#endif
215
216#ifndef __ASSEMBLY__
217
218/*
219 * PFNs are used to describe any physical page; this means
220 * PFN 0 == physical address 0.
221 *
222 * This is the PFN of the first RAM page in the kernel
223 * direct-mapped view. We assume this is the first page
224 * of RAM in the mem_map as well.
225 */
226#define PHYS_PFN_OFFSET ((unsigned long)(PHYS_OFFSET >> PAGE_SHIFT))
227
228/*
229 * These are *only* valid on the kernel direct mapped RAM memory.
230 * Note: Drivers should NOT use these. They are the wrong
231 * translation for translating DMA addresses. Use the driver
232 * DMA support - see dma-mapping.h.
233 */
234static inline phys_addr_t virt_to_phys(const volatile void *x)
235{
236 return __virt_to_phys((unsigned long)(x));
237}
238
239static inline void *phys_to_virt(phys_addr_t x)
240{
241 return (void *)(__phys_to_virt((unsigned long)(x)));
242}
243
244/*
245 * Drivers should NOT use these either.
246 */
247#define __pa(x) __virt_to_phys((unsigned long)(x))
248#define __va(x) ((void *)__phys_to_virt((unsigned long)(x)))
249#define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT)
250
251/*
252 * Virtual <-> DMA view memory address translations
253 * Again, these are *only* valid on the kernel direct mapped RAM
254 * memory. Use of these is *deprecated* (and that doesn't mean
255 * use the __ prefixed forms instead.) See dma-mapping.h.
256 */
257#ifndef __virt_to_bus
258#define __virt_to_bus __virt_to_phys
259#define __bus_to_virt __phys_to_virt
260#define __pfn_to_bus(x) __pfn_to_phys(x)
261#define __bus_to_pfn(x) __phys_to_pfn(x)
262#endif
263
264#ifdef CONFIG_VIRT_TO_BUS
265static inline __deprecated unsigned long virt_to_bus(void *x)
266{
267 return __virt_to_bus((unsigned long)x);
268}
269
270static inline __deprecated void *bus_to_virt(unsigned long x)
271{
272 return (void *)__bus_to_virt(x);
273}
274#endif
275
276/*
277 * Conversion between a struct page and a physical address.
278 *
279 * page_to_pfn(page) convert a struct page * to a PFN number
280 * pfn_to_page(pfn) convert a _valid_ PFN number to struct page *
281 *
282 * virt_to_page(k) convert a _valid_ virtual address to struct page *
283 * virt_addr_valid(k) indicates whether a virtual address is valid
284 */
285#define ARCH_PFN_OFFSET PHYS_PFN_OFFSET
286
287#define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
288#define virt_addr_valid(kaddr) ((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory)
289
290#endif
291
292#include <asm-generic/memory_model.h>
293
294#endif