xref: /linux/arch/arm/include/asm/memory.h (revision 54f5a57e266318d72f84fda95805099986a7e201)
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 /* PAGE_OFFSET - the virtual address of the start of the kernel image */
34 #define PAGE_OFFSET		UL(CONFIG_PAGE_OFFSET)
35 
36 #ifdef CONFIG_MMU
37 
38 /*
39  * TASK_SIZE - the maximum size of a user space task.
40  * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area
41  */
42 #define TASK_SIZE		(UL(CONFIG_PAGE_OFFSET) - UL(SZ_16M))
43 #define TASK_UNMAPPED_BASE	ALIGN(TASK_SIZE / 3, SZ_16M)
44 
45 /*
46  * The maximum size of a 26-bit user space task.
47  */
48 #define TASK_SIZE_26		(UL(1) << 26)
49 
50 /*
51  * The module space lives between the addresses given by TASK_SIZE
52  * and PAGE_OFFSET - it must be within 32MB of the kernel text.
53  */
54 #ifndef CONFIG_THUMB2_KERNEL
55 #define MODULES_VADDR		(PAGE_OFFSET - SZ_16M)
56 #else
57 /* smaller range for Thumb-2 symbols relocation (2^24)*/
58 #define MODULES_VADDR		(PAGE_OFFSET - SZ_8M)
59 #endif
60 
61 #if TASK_SIZE > MODULES_VADDR
62 #error Top of user space clashes with start of module space
63 #endif
64 
65 /*
66  * The highmem pkmap virtual space shares the end of the module area.
67  */
68 #ifdef CONFIG_HIGHMEM
69 #define MODULES_END		(PAGE_OFFSET - PMD_SIZE)
70 #else
71 #define MODULES_END		(PAGE_OFFSET)
72 #endif
73 
74 /*
75  * The XIP kernel gets mapped at the bottom of the module vm area.
76  * Since we use sections to map it, this macro replaces the physical address
77  * with its virtual address while keeping offset from the base section.
78  */
79 #define XIP_VIRT_ADDR(physaddr)  (MODULES_VADDR + ((physaddr) & 0x000fffff))
80 
81 /*
82  * Allow 16MB-aligned ioremap pages
83  */
84 #define IOREMAP_MAX_ORDER	24
85 
86 #define CONSISTENT_END		(0xffe00000UL)
87 
88 #else /* CONFIG_MMU */
89 
90 /*
91  * The limitation of user task size can grow up to the end of free ram region.
92  * It is difficult to define and perhaps will never meet the original meaning
93  * of this define that was meant to.
94  * Fortunately, there is no reference for this in noMMU mode, for now.
95  */
96 #ifndef TASK_SIZE
97 #define TASK_SIZE		(CONFIG_DRAM_SIZE)
98 #endif
99 
100 #ifndef TASK_UNMAPPED_BASE
101 #define TASK_UNMAPPED_BASE	UL(0x00000000)
102 #endif
103 
104 #ifndef END_MEM
105 #define END_MEM     		(UL(CONFIG_DRAM_BASE) + CONFIG_DRAM_SIZE)
106 #endif
107 
108 /*
109  * The module can be at any place in ram in nommu mode.
110  */
111 #define MODULES_END		(END_MEM)
112 #define MODULES_VADDR		PAGE_OFFSET
113 
114 #define XIP_VIRT_ADDR(physaddr)  (physaddr)
115 
116 #endif /* !CONFIG_MMU */
117 
118 /*
119  * We fix the TCM memories max 32 KiB ITCM resp DTCM at these
120  * locations
121  */
122 #ifdef CONFIG_HAVE_TCM
123 #define ITCM_OFFSET	UL(0xfffe0000)
124 #define DTCM_OFFSET	UL(0xfffe8000)
125 #endif
126 
127 /*
128  * Convert a physical address to a Page Frame Number and back
129  */
130 #define	__phys_to_pfn(paddr)	((unsigned long)((paddr) >> PAGE_SHIFT))
131 #define	__pfn_to_phys(pfn)	((phys_addr_t)(pfn) << PAGE_SHIFT)
132 
133 /*
134  * Convert a page to/from a physical address
135  */
136 #define page_to_phys(page)	(__pfn_to_phys(page_to_pfn(page)))
137 #define phys_to_page(phys)	(pfn_to_page(__phys_to_pfn(phys)))
138 
139 /*
140  * Minimum guaranted alignment in pgd_alloc().  The page table pointers passed
141  * around in head.S and proc-*.S are shifted by this amount, in order to
142  * leave spare high bits for systems with physical address extension.  This
143  * does not fully accomodate the 40-bit addressing capability of ARM LPAE, but
144  * gives us about 38-bits or so.
145  */
146 #ifdef CONFIG_ARM_LPAE
147 #define ARCH_PGD_SHIFT		L1_CACHE_SHIFT
148 #else
149 #define ARCH_PGD_SHIFT		0
150 #endif
151 #define ARCH_PGD_MASK		((1 << ARCH_PGD_SHIFT) - 1)
152 
153 /*
154  * PLAT_PHYS_OFFSET is the offset (from zero) of the start of physical
155  * memory.  This is used for XIP and NoMMU kernels, or by kernels which
156  * have their own mach/memory.h.  Assembly code must always use
157  * PLAT_PHYS_OFFSET and not PHYS_OFFSET.
158  */
159 #ifndef PLAT_PHYS_OFFSET
160 #define PLAT_PHYS_OFFSET	UL(CONFIG_PHYS_OFFSET)
161 #endif
162 
163 #ifndef __ASSEMBLY__
164 
165 /*
166  * Physical vs virtual RAM address space conversion.  These are
167  * private definitions which should NOT be used outside memory.h
168  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
169  */
170 #ifndef __virt_to_phys
171 #ifdef CONFIG_ARM_PATCH_PHYS_VIRT
172 
173 /*
174  * Constants used to force the right instruction encodings and shifts
175  * so that all we need to do is modify the 8-bit constant field.
176  */
177 #define __PV_BITS_31_24	0x81000000
178 #define __PV_BITS_7_0	0x81
179 
180 extern u64 __pv_phys_offset;
181 extern u64 __pv_offset;
182 extern void fixup_pv_table(const void *, unsigned long);
183 extern const void *__pv_table_begin, *__pv_table_end;
184 
185 #define PHYS_OFFSET __pv_phys_offset
186 
187 #define __pv_stub(from,to,instr,type)			\
188 	__asm__("@ __pv_stub\n"				\
189 	"1:	" instr "	%0, %1, %2\n"		\
190 	"	.pushsection .pv_table,\"a\"\n"		\
191 	"	.long	1b\n"				\
192 	"	.popsection\n"				\
193 	: "=r" (to)					\
194 	: "r" (from), "I" (type))
195 
196 #define __pv_stub_mov_hi(t)				\
197 	__asm__ volatile("@ __pv_stub_mov\n"		\
198 	"1:	mov	%R0, %1\n"			\
199 	"	.pushsection .pv_table,\"a\"\n"		\
200 	"	.long	1b\n"				\
201 	"	.popsection\n"				\
202 	: "=r" (t)					\
203 	: "I" (__PV_BITS_7_0))
204 
205 #define __pv_add_carry_stub(x, y)			\
206 	__asm__ volatile("@ __pv_add_carry_stub\n"	\
207 	"1:	adds	%Q0, %1, %2\n"			\
208 	"	adc	%R0, %R0, #0\n"			\
209 	"	.pushsection .pv_table,\"a\"\n"		\
210 	"	.long	1b\n"				\
211 	"	.popsection\n"				\
212 	: "+r" (y)					\
213 	: "r" (x), "I" (__PV_BITS_31_24)		\
214 	: "cc")
215 
216 static inline phys_addr_t __virt_to_phys(unsigned long x)
217 {
218 	phys_addr_t t;
219 
220 	if (sizeof(phys_addr_t) == 4) {
221 		__pv_stub(x, t, "add", __PV_BITS_31_24);
222 	} else {
223 		__pv_stub_mov_hi(t);
224 		__pv_add_carry_stub(x, t);
225 	}
226 	return t;
227 }
228 
229 static inline unsigned long __phys_to_virt(phys_addr_t x)
230 {
231 	unsigned long t;
232 
233 	/*
234 	 * 'unsigned long' cast discard upper word when
235 	 * phys_addr_t is 64 bit, and makes sure that inline
236 	 * assembler expression receives 32 bit argument
237 	 * in place where 'r' 32 bit operand is expected.
238 	 */
239 	__pv_stub((unsigned long) x, t, "sub", __PV_BITS_31_24);
240 	return t;
241 }
242 
243 #else
244 
245 #define PHYS_OFFSET	PLAT_PHYS_OFFSET
246 
247 static inline phys_addr_t __virt_to_phys(unsigned long x)
248 {
249 	return (phys_addr_t)x - PAGE_OFFSET + PHYS_OFFSET;
250 }
251 
252 static inline unsigned long __phys_to_virt(phys_addr_t x)
253 {
254 	return x - PHYS_OFFSET + PAGE_OFFSET;
255 }
256 
257 #endif
258 #endif
259 
260 /*
261  * PFNs are used to describe any physical page; this means
262  * PFN 0 == physical address 0.
263  *
264  * This is the PFN of the first RAM page in the kernel
265  * direct-mapped view.  We assume this is the first page
266  * of RAM in the mem_map as well.
267  */
268 #define PHYS_PFN_OFFSET	((unsigned long)(PHYS_OFFSET >> PAGE_SHIFT))
269 
270 /*
271  * These are *only* valid on the kernel direct mapped RAM memory.
272  * Note: Drivers should NOT use these.  They are the wrong
273  * translation for translating DMA addresses.  Use the driver
274  * DMA support - see dma-mapping.h.
275  */
276 static inline phys_addr_t virt_to_phys(const volatile void *x)
277 {
278 	return __virt_to_phys((unsigned long)(x));
279 }
280 
281 static inline void *phys_to_virt(phys_addr_t x)
282 {
283 	return (void *)__phys_to_virt(x);
284 }
285 
286 /*
287  * Drivers should NOT use these either.
288  */
289 #define __pa(x)			__virt_to_phys((unsigned long)(x))
290 #define __va(x)			((void *)__phys_to_virt((phys_addr_t)(x)))
291 #define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
292 
293 extern phys_addr_t (*arch_virt_to_idmap)(unsigned long x);
294 
295 /*
296  * These are for systems that have a hardware interconnect supported alias of
297  * physical memory for idmap purposes.  Most cases should leave these
298  * untouched.
299  */
300 static inline phys_addr_t __virt_to_idmap(unsigned long x)
301 {
302 	if (arch_virt_to_idmap)
303 		return arch_virt_to_idmap(x);
304 	else
305 		return __virt_to_phys(x);
306 }
307 
308 #define virt_to_idmap(x)	__virt_to_idmap((unsigned long)(x))
309 
310 /*
311  * Virtual <-> DMA view memory address translations
312  * Again, these are *only* valid on the kernel direct mapped RAM
313  * memory.  Use of these is *deprecated* (and that doesn't mean
314  * use the __ prefixed forms instead.)  See dma-mapping.h.
315  */
316 #ifndef __virt_to_bus
317 #define __virt_to_bus	__virt_to_phys
318 #define __bus_to_virt	__phys_to_virt
319 #define __pfn_to_bus(x)	__pfn_to_phys(x)
320 #define __bus_to_pfn(x)	__phys_to_pfn(x)
321 #endif
322 
323 #ifdef CONFIG_VIRT_TO_BUS
324 static inline __deprecated unsigned long virt_to_bus(void *x)
325 {
326 	return __virt_to_bus((unsigned long)x);
327 }
328 
329 static inline __deprecated void *bus_to_virt(unsigned long x)
330 {
331 	return (void *)__bus_to_virt(x);
332 }
333 #endif
334 
335 /*
336  * Conversion between a struct page and a physical address.
337  *
338  *  page_to_pfn(page)	convert a struct page * to a PFN number
339  *  pfn_to_page(pfn)	convert a _valid_ PFN number to struct page *
340  *
341  *  virt_to_page(k)	convert a _valid_ virtual address to struct page *
342  *  virt_addr_valid(k)	indicates whether a virtual address is valid
343  */
344 #define ARCH_PFN_OFFSET		PHYS_PFN_OFFSET
345 
346 #define virt_to_page(kaddr)	pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
347 #define virt_addr_valid(kaddr)	(((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory) \
348 					&& pfn_valid(__pa(kaddr) >> PAGE_SHIFT) )
349 
350 #endif
351 
352 #include <asm-generic/memory_model.h>
353 
354 #endif
355