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 <asm/sizes.h>
20 
21 #ifdef CONFIG_NEED_MACH_MEMORY_H
22 #include <mach/memory.h>
23 #endif
24 
25 /*
26  * Allow for constants defined here to be used from assembly code
27  * by prepending the UL suffix only with actual C code compilation.
28  */
29 #define UL(x) _AC(x, UL)
30 
31 #ifdef CONFIG_MMU
32 
33 /*
34  * PAGE_OFFSET - the virtual address of the start of the kernel image
35  * TASK_SIZE - the maximum size of a user space task.
36  * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area
37  */
38 #define PAGE_OFFSET		UL(CONFIG_PAGE_OFFSET)
39 #define TASK_SIZE		(UL(CONFIG_PAGE_OFFSET) - UL(0x01000000))
40 #define TASK_UNMAPPED_BASE	(UL(CONFIG_PAGE_OFFSET) / 3)
41 
42 /*
43  * The maximum size of a 26-bit user space task.
44  */
45 #define TASK_SIZE_26		UL(0x04000000)
46 
47 /*
48  * The module space lives between the addresses given by TASK_SIZE
49  * and PAGE_OFFSET - it must be within 32MB of the kernel text.
50  */
51 #ifndef CONFIG_THUMB2_KERNEL
52 #define MODULES_VADDR		(PAGE_OFFSET - 16*1024*1024)
53 #else
54 /* smaller range for Thumb-2 symbols relocation (2^24)*/
55 #define MODULES_VADDR		(PAGE_OFFSET - 8*1024*1024)
56 #endif
57 
58 #if TASK_SIZE > MODULES_VADDR
59 #error Top of user space clashes with start of module space
60 #endif
61 
62 /*
63  * The highmem pkmap virtual space shares the end of the module area.
64  */
65 #ifdef CONFIG_HIGHMEM
66 #define MODULES_END		(PAGE_OFFSET - PMD_SIZE)
67 #else
68 #define MODULES_END		(PAGE_OFFSET)
69 #endif
70 
71 /*
72  * The XIP kernel gets mapped at the bottom of the module vm area.
73  * Since we use sections to map it, this macro replaces the physical address
74  * with its virtual address while keeping offset from the base section.
75  */
76 #define XIP_VIRT_ADDR(physaddr)  (MODULES_VADDR + ((physaddr) & 0x000fffff))
77 
78 /*
79  * Allow 16MB-aligned ioremap pages
80  */
81 #define IOREMAP_MAX_ORDER	24
82 
83 #define CONSISTENT_END		(0xffe00000UL)
84 
85 #else /* CONFIG_MMU */
86 
87 /*
88  * The limitation of user task size can grow up to the end of free ram region.
89  * It is difficult to define and perhaps will never meet the original meaning
90  * of this define that was meant to.
91  * Fortunately, there is no reference for this in noMMU mode, for now.
92  */
93 #ifndef TASK_SIZE
94 #define TASK_SIZE		(CONFIG_DRAM_SIZE)
95 #endif
96 
97 #ifndef TASK_UNMAPPED_BASE
98 #define TASK_UNMAPPED_BASE	UL(0x00000000)
99 #endif
100 
101 #ifndef PHYS_OFFSET
102 #define PHYS_OFFSET 		UL(CONFIG_DRAM_BASE)
103 #endif
104 
105 #ifndef END_MEM
106 #define END_MEM     		(UL(CONFIG_DRAM_BASE) + CONFIG_DRAM_SIZE)
107 #endif
108 
109 #ifndef PAGE_OFFSET
110 #define PAGE_OFFSET		(PHYS_OFFSET)
111 #endif
112 
113 /*
114  * The module can be at any place in ram in nommu mode.
115  */
116 #define MODULES_END		(END_MEM)
117 #define MODULES_VADDR		(PHYS_OFFSET)
118 
119 #define XIP_VIRT_ADDR(physaddr)  (physaddr)
120 
121 #endif /* !CONFIG_MMU */
122 
123 /*
124  * We fix the TCM memories max 32 KiB ITCM resp DTCM at these
125  * locations
126  */
127 #ifdef CONFIG_HAVE_TCM
128 #define ITCM_OFFSET	UL(0xfffe0000)
129 #define DTCM_OFFSET	UL(0xfffe8000)
130 #endif
131 
132 /*
133  * Convert a physical address to a Page Frame Number and back
134  */
135 #define	__phys_to_pfn(paddr)	((unsigned long)((paddr) >> PAGE_SHIFT))
136 #define	__pfn_to_phys(pfn)	((phys_addr_t)(pfn) << PAGE_SHIFT)
137 
138 /*
139  * Convert a page to/from a physical address
140  */
141 #define page_to_phys(page)	(__pfn_to_phys(page_to_pfn(page)))
142 #define phys_to_page(phys)	(pfn_to_page(__phys_to_pfn(phys)))
143 
144 #ifndef __ASSEMBLY__
145 
146 /*
147  * Physical vs virtual RAM address space conversion.  These are
148  * private definitions which should NOT be used outside memory.h
149  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
150  */
151 #ifndef __virt_to_phys
152 #ifdef CONFIG_ARM_PATCH_PHYS_VIRT
153 
154 /*
155  * Constants used to force the right instruction encodings and shifts
156  * so that all we need to do is modify the 8-bit constant field.
157  */
158 #define __PV_BITS_31_24	0x81000000
159 
160 extern unsigned long __pv_phys_offset;
161 #define PHYS_OFFSET __pv_phys_offset
162 
163 #define __pv_stub(from,to,instr,type)			\
164 	__asm__("@ __pv_stub\n"				\
165 	"1:	" instr "	%0, %1, %2\n"		\
166 	"	.pushsection .pv_table,\"a\"\n"		\
167 	"	.long	1b\n"				\
168 	"	.popsection\n"				\
169 	: "=r" (to)					\
170 	: "r" (from), "I" (type))
171 
__virt_to_phys(unsigned long x)172 static inline unsigned long __virt_to_phys(unsigned long x)
173 {
174 	unsigned long t;
175 	__pv_stub(x, t, "add", __PV_BITS_31_24);
176 	return t;
177 }
178 
__phys_to_virt(unsigned long x)179 static inline unsigned long __phys_to_virt(unsigned long x)
180 {
181 	unsigned long t;
182 	__pv_stub(x, t, "sub", __PV_BITS_31_24);
183 	return t;
184 }
185 #else
186 #define __virt_to_phys(x)	((x) - PAGE_OFFSET + PHYS_OFFSET)
187 #define __phys_to_virt(x)	((x) - PHYS_OFFSET + PAGE_OFFSET)
188 #endif
189 #endif
190 
191 #ifndef PHYS_OFFSET
192 #ifdef PLAT_PHYS_OFFSET
193 #define PHYS_OFFSET	PLAT_PHYS_OFFSET
194 #else
195 #define PHYS_OFFSET	UL(CONFIG_PHYS_OFFSET)
196 #endif
197 #endif
198 
199 /*
200  * PFNs are used to describe any physical page; this means
201  * PFN 0 == physical address 0.
202  *
203  * This is the PFN of the first RAM page in the kernel
204  * direct-mapped view.  We assume this is the first page
205  * of RAM in the mem_map as well.
206  */
207 #define PHYS_PFN_OFFSET	(PHYS_OFFSET >> PAGE_SHIFT)
208 
209 /*
210  * These are *only* valid on the kernel direct mapped RAM memory.
211  * Note: Drivers should NOT use these.  They are the wrong
212  * translation for translating DMA addresses.  Use the driver
213  * DMA support - see dma-mapping.h.
214  */
virt_to_phys(const volatile void * x)215 static inline phys_addr_t virt_to_phys(const volatile void *x)
216 {
217 	return __virt_to_phys((unsigned long)(x));
218 }
219 
phys_to_virt(phys_addr_t x)220 static inline void *phys_to_virt(phys_addr_t x)
221 {
222 	return (void *)(__phys_to_virt((unsigned long)(x)));
223 }
224 
225 /*
226  * Drivers should NOT use these either.
227  */
228 #define __pa(x)			__virt_to_phys((unsigned long)(x))
229 #define __va(x)			((void *)__phys_to_virt((unsigned long)(x)))
230 #define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
231 
232 /*
233  * Virtual <-> DMA view memory address translations
234  * Again, these are *only* valid on the kernel direct mapped RAM
235  * memory.  Use of these is *deprecated* (and that doesn't mean
236  * use the __ prefixed forms instead.)  See dma-mapping.h.
237  */
238 #ifndef __virt_to_bus
239 #define __virt_to_bus	__virt_to_phys
240 #define __bus_to_virt	__phys_to_virt
241 #define __pfn_to_bus(x)	__pfn_to_phys(x)
242 #define __bus_to_pfn(x)	__phys_to_pfn(x)
243 #endif
244 
virt_to_bus(void * x)245 static inline __deprecated unsigned long virt_to_bus(void *x)
246 {
247 	return __virt_to_bus((unsigned long)x);
248 }
249 
bus_to_virt(unsigned long x)250 static inline __deprecated void *bus_to_virt(unsigned long x)
251 {
252 	return (void *)__bus_to_virt(x);
253 }
254 
255 /*
256  * Conversion between a struct page and a physical address.
257  *
258  * Note: when converting an unknown physical address to a
259  * struct page, the resulting pointer must be validated
260  * using VALID_PAGE().  It must return an invalid struct page
261  * for any physical address not corresponding to a system
262  * RAM address.
263  *
264  *  page_to_pfn(page)	convert a struct page * to a PFN number
265  *  pfn_to_page(pfn)	convert a _valid_ PFN number to struct page *
266  *
267  *  virt_to_page(k)	convert a _valid_ virtual address to struct page *
268  *  virt_addr_valid(k)	indicates whether a virtual address is valid
269  */
270 #define ARCH_PFN_OFFSET		PHYS_PFN_OFFSET
271 
272 #define virt_to_page(kaddr)	pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
273 #define virt_addr_valid(kaddr)	((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory)
274 
275 /*
276  * Optional coherency support.  Currently used only by selected
277  * Intel XSC3-based systems.
278  */
279 #ifndef arch_is_coherent
280 #define arch_is_coherent()		0
281 #endif
282 
283 #endif
284 
285 #include <asm-generic/memory_model.h>
286 
287 #endif
288