Linux kernel mirror (for testing)
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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 <mach/memory.h>
20#include <asm/sizes.h>
21
22/*
23 * Allow for constants defined here to be used from assembly code
24 * by prepending the UL suffix only with actual C code compilation.
25 */
26#define UL(x) _AC(x, UL)
27
28#ifdef CONFIG_MMU
29
30/*
31 * PAGE_OFFSET - the virtual address of the start of the kernel image
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 PAGE_OFFSET UL(CONFIG_PAGE_OFFSET)
36#define TASK_SIZE (UL(CONFIG_PAGE_OFFSET) - UL(0x01000000))
37#define TASK_UNMAPPED_BASE (UL(CONFIG_PAGE_OFFSET) / 3)
38
39/*
40 * The maximum size of a 26-bit user space task.
41 */
42#define TASK_SIZE_26 UL(0x04000000)
43
44/*
45 * The module space lives between the addresses given by TASK_SIZE
46 * and PAGE_OFFSET - it must be within 32MB of the kernel text.
47 */
48#ifndef CONFIG_THUMB2_KERNEL
49#define MODULES_VADDR (PAGE_OFFSET - 16*1024*1024)
50#else
51/* smaller range for Thumb-2 symbols relocation (2^24)*/
52#define MODULES_VADDR (PAGE_OFFSET - 8*1024*1024)
53#endif
54
55#if TASK_SIZE > MODULES_VADDR
56#error Top of user space clashes with start of module space
57#endif
58
59/*
60 * The highmem pkmap virtual space shares the end of the module area.
61 */
62#ifdef CONFIG_HIGHMEM
63#define MODULES_END (PAGE_OFFSET - PMD_SIZE)
64#else
65#define MODULES_END (PAGE_OFFSET)
66#endif
67
68/*
69 * The XIP kernel gets mapped at the bottom of the module vm area.
70 * Since we use sections to map it, this macro replaces the physical address
71 * with its virtual address while keeping offset from the base section.
72 */
73#define XIP_VIRT_ADDR(physaddr) (MODULES_VADDR + ((physaddr) & 0x000fffff))
74
75/*
76 * Allow 16MB-aligned ioremap pages
77 */
78#define IOREMAP_MAX_ORDER 24
79
80/*
81 * Size of DMA-consistent memory region. Must be multiple of 2M,
82 * between 2MB and 14MB inclusive.
83 */
84#ifndef CONSISTENT_DMA_SIZE
85#define CONSISTENT_DMA_SIZE SZ_2M
86#endif
87
88#define CONSISTENT_END (0xffe00000UL)
89#define CONSISTENT_BASE (CONSISTENT_END - CONSISTENT_DMA_SIZE)
90
91#else /* CONFIG_MMU */
92
93/*
94 * The limitation of user task size can grow up to the end of free ram region.
95 * It is difficult to define and perhaps will never meet the original meaning
96 * of this define that was meant to.
97 * Fortunately, there is no reference for this in noMMU mode, for now.
98 */
99#ifndef TASK_SIZE
100#define TASK_SIZE (CONFIG_DRAM_SIZE)
101#endif
102
103#ifndef TASK_UNMAPPED_BASE
104#define TASK_UNMAPPED_BASE UL(0x00000000)
105#endif
106
107#ifndef PHYS_OFFSET
108#define PHYS_OFFSET UL(CONFIG_DRAM_BASE)
109#endif
110
111#ifndef END_MEM
112#define END_MEM (UL(CONFIG_DRAM_BASE) + CONFIG_DRAM_SIZE)
113#endif
114
115#ifndef PAGE_OFFSET
116#define PAGE_OFFSET (PHYS_OFFSET)
117#endif
118
119/*
120 * The module can be at any place in ram in nommu mode.
121 */
122#define MODULES_END (END_MEM)
123#define MODULES_VADDR (PHYS_OFFSET)
124
125#endif /* !CONFIG_MMU */
126
127/*
128 * We fix the TCM memories max 32 KiB ITCM resp DTCM at these
129 * locations
130 */
131#ifdef CONFIG_HAVE_TCM
132#define ITCM_OFFSET UL(0xfffe0000)
133#define DTCM_OFFSET UL(0xfffe8000)
134#endif
135
136/*
137 * Convert a physical address to a Page Frame Number and back
138 */
139#define __phys_to_pfn(paddr) ((unsigned long)((paddr) >> PAGE_SHIFT))
140#define __pfn_to_phys(pfn) ((phys_addr_t)(pfn) << PAGE_SHIFT)
141
142/*
143 * Convert a page to/from a physical address
144 */
145#define page_to_phys(page) (__pfn_to_phys(page_to_pfn(page)))
146#define phys_to_page(phys) (pfn_to_page(__phys_to_pfn(phys)))
147
148#ifndef __ASSEMBLY__
149
150/*
151 * Physical vs virtual RAM address space conversion. These are
152 * private definitions which should NOT be used outside memory.h
153 * files. Use virt_to_phys/phys_to_virt/__pa/__va instead.
154 */
155#ifndef __virt_to_phys
156#ifdef CONFIG_ARM_PATCH_PHYS_VIRT
157
158/*
159 * Constants used to force the right instruction encodings and shifts
160 * so that all we need to do is modify the 8-bit constant field.
161 */
162#define __PV_BITS_31_24 0x81000000
163#define __PV_BITS_23_16 0x00810000
164
165extern unsigned long __pv_phys_offset;
166#define PHYS_OFFSET __pv_phys_offset
167
168#define __pv_stub(from,to,instr,type) \
169 __asm__("@ __pv_stub\n" \
170 "1: " instr " %0, %1, %2\n" \
171 " .pushsection .pv_table,\"a\"\n" \
172 " .long 1b\n" \
173 " .popsection\n" \
174 : "=r" (to) \
175 : "r" (from), "I" (type))
176
177static inline unsigned long __virt_to_phys(unsigned long x)
178{
179 unsigned long t;
180 __pv_stub(x, t, "add", __PV_BITS_31_24);
181#ifdef CONFIG_ARM_PATCH_PHYS_VIRT_16BIT
182 __pv_stub(t, t, "add", __PV_BITS_23_16);
183#endif
184 return t;
185}
186
187static inline unsigned long __phys_to_virt(unsigned long x)
188{
189 unsigned long t;
190 __pv_stub(x, t, "sub", __PV_BITS_31_24);
191#ifdef CONFIG_ARM_PATCH_PHYS_VIRT_16BIT
192 __pv_stub(t, t, "sub", __PV_BITS_23_16);
193#endif
194 return t;
195}
196#else
197#define __virt_to_phys(x) ((x) - PAGE_OFFSET + PHYS_OFFSET)
198#define __phys_to_virt(x) ((x) - PHYS_OFFSET + PAGE_OFFSET)
199#endif
200#endif
201
202#ifndef PHYS_OFFSET
203#define PHYS_OFFSET PLAT_PHYS_OFFSET
204#endif
205
206/*
207 * The DMA mask corresponding to the maximum bus address allocatable
208 * using GFP_DMA. The default here places no restriction on DMA
209 * allocations. This must be the smallest DMA mask in the system,
210 * so a successful GFP_DMA allocation will always satisfy this.
211 */
212#ifndef ISA_DMA_THRESHOLD
213#define ISA_DMA_THRESHOLD (0xffffffffULL)
214#endif
215
216#ifndef arch_adjust_zones
217#define arch_adjust_zones(size,holes) do { } while (0)
218#elif !defined(CONFIG_ZONE_DMA)
219#error "custom arch_adjust_zones() requires CONFIG_ZONE_DMA"
220#endif
221
222/*
223 * PFNs are used to describe any physical page; this means
224 * PFN 0 == physical address 0.
225 *
226 * This is the PFN of the first RAM page in the kernel
227 * direct-mapped view. We assume this is the first page
228 * of RAM in the mem_map as well.
229 */
230#define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
231
232/*
233 * These are *only* valid on the kernel direct mapped RAM memory.
234 * Note: Drivers should NOT use these. They are the wrong
235 * translation for translating DMA addresses. Use the driver
236 * DMA support - see dma-mapping.h.
237 */
238static inline phys_addr_t virt_to_phys(const volatile void *x)
239{
240 return __virt_to_phys((unsigned long)(x));
241}
242
243static inline void *phys_to_virt(phys_addr_t x)
244{
245 return (void *)(__phys_to_virt((unsigned long)(x)));
246}
247
248/*
249 * Drivers should NOT use these either.
250 */
251#define __pa(x) __virt_to_phys((unsigned long)(x))
252#define __va(x) ((void *)__phys_to_virt((unsigned long)(x)))
253#define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT)
254
255/*
256 * Virtual <-> DMA view memory address translations
257 * Again, these are *only* valid on the kernel direct mapped RAM
258 * memory. Use of these is *deprecated* (and that doesn't mean
259 * use the __ prefixed forms instead.) See dma-mapping.h.
260 */
261#ifndef __virt_to_bus
262#define __virt_to_bus __virt_to_phys
263#define __bus_to_virt __phys_to_virt
264#define __pfn_to_bus(x) __pfn_to_phys(x)
265#define __bus_to_pfn(x) __phys_to_pfn(x)
266#endif
267
268static inline __deprecated unsigned long virt_to_bus(void *x)
269{
270 return __virt_to_bus((unsigned long)x);
271}
272
273static inline __deprecated void *bus_to_virt(unsigned long x)
274{
275 return (void *)__bus_to_virt(x);
276}
277
278/*
279 * Conversion between a struct page and a physical address.
280 *
281 * Note: when converting an unknown physical address to a
282 * struct page, the resulting pointer must be validated
283 * using VALID_PAGE(). It must return an invalid struct page
284 * for any physical address not corresponding to a system
285 * RAM address.
286 *
287 * page_to_pfn(page) convert a struct page * to a PFN number
288 * pfn_to_page(pfn) convert a _valid_ PFN number to struct page *
289 *
290 * virt_to_page(k) convert a _valid_ virtual address to struct page *
291 * virt_addr_valid(k) indicates whether a virtual address is valid
292 */
293#define ARCH_PFN_OFFSET PHYS_PFN_OFFSET
294
295#define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
296#define virt_addr_valid(kaddr) ((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory)
297
298/*
299 * Optional coherency support. Currently used only by selected
300 * Intel XSC3-based systems.
301 */
302#ifndef arch_is_coherent
303#define arch_is_coherent() 0
304#endif
305
306#endif
307
308#include <asm-generic/memory_model.h>
309
310#endif