xref: /linux/arch/arm/include/asm/memory.h (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
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 #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 /* PAGE_OFFSET - the virtual address of the start of the kernel image */
32 #define PAGE_OFFSET		UL(CONFIG_PAGE_OFFSET)
33 
34 #ifdef CONFIG_MMU
35 
36 /*
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 TASK_SIZE		(UL(CONFIG_PAGE_OFFSET) - UL(SZ_16M))
41 #define TASK_UNMAPPED_BASE	ALIGN(TASK_SIZE / 3, SZ_16M)
42 
43 /*
44  * The maximum size of a 26-bit user space task.
45  */
46 #define TASK_SIZE_26		(UL(1) << 26)
47 
48 /*
49  * The module space lives between the addresses given by TASK_SIZE
50  * and PAGE_OFFSET - it must be within 32MB of the kernel text.
51  */
52 #ifndef CONFIG_THUMB2_KERNEL
53 #define MODULES_VADDR		(PAGE_OFFSET - SZ_16M)
54 #else
55 /* smaller range for Thumb-2 symbols relocation (2^24)*/
56 #define MODULES_VADDR		(PAGE_OFFSET - SZ_8M)
57 #endif
58 
59 #if TASK_SIZE > MODULES_VADDR
60 #error Top of user space clashes with start of module space
61 #endif
62 
63 /*
64  * The highmem pkmap virtual space shares the end of the module area.
65  */
66 #ifdef CONFIG_HIGHMEM
67 #define MODULES_END		(PAGE_OFFSET - PMD_SIZE)
68 #else
69 #define MODULES_END		(PAGE_OFFSET)
70 #endif
71 
72 /*
73  * The XIP kernel gets mapped at the bottom of the module vm area.
74  * Since we use sections to map it, this macro replaces the physical address
75  * with its virtual address while keeping offset from the base section.
76  */
77 #define XIP_VIRT_ADDR(physaddr)  (MODULES_VADDR + ((physaddr) & 0x000fffff))
78 
79 /*
80  * Allow 16MB-aligned ioremap pages
81  */
82 #define IOREMAP_MAX_ORDER	24
83 
84 #else /* CONFIG_MMU */
85 
86 /*
87  * The limitation of user task size can grow up to the end of free ram region.
88  * It is difficult to define and perhaps will never meet the original meaning
89  * of this define that was meant to.
90  * Fortunately, there is no reference for this in noMMU mode, for now.
91  */
92 #define TASK_SIZE		UL(0xffffffff)
93 
94 #ifndef TASK_UNMAPPED_BASE
95 #define TASK_UNMAPPED_BASE	UL(0x00000000)
96 #endif
97 
98 #ifndef END_MEM
99 #define END_MEM     		(UL(CONFIG_DRAM_BASE) + CONFIG_DRAM_SIZE)
100 #endif
101 
102 /*
103  * The module can be at any place in ram in nommu mode.
104  */
105 #define MODULES_END		(END_MEM)
106 #define MODULES_VADDR		PAGE_OFFSET
107 
108 #define XIP_VIRT_ADDR(physaddr)  (physaddr)
109 
110 #endif /* !CONFIG_MMU */
111 
112 /*
113  * We fix the TCM memories max 32 KiB ITCM resp DTCM at these
114  * locations
115  */
116 #ifdef CONFIG_HAVE_TCM
117 #define ITCM_OFFSET	UL(0xfffe0000)
118 #define DTCM_OFFSET	UL(0xfffe8000)
119 #endif
120 
121 /*
122  * Convert a page to/from a physical address
123  */
124 #define page_to_phys(page)	(__pfn_to_phys(page_to_pfn(page)))
125 #define phys_to_page(phys)	(pfn_to_page(__phys_to_pfn(phys)))
126 
127 /*
128  * PLAT_PHYS_OFFSET is the offset (from zero) of the start of physical
129  * memory.  This is used for XIP and NoMMU kernels, and on platforms that don't
130  * have CONFIG_ARM_PATCH_PHYS_VIRT. Assembly code must always use
131  * PLAT_PHYS_OFFSET and not PHYS_OFFSET.
132  */
133 #define PLAT_PHYS_OFFSET	UL(CONFIG_PHYS_OFFSET)
134 
135 #ifndef __ASSEMBLY__
136 
137 /*
138  * Physical vs virtual RAM address space conversion.  These are
139  * private definitions which should NOT be used outside memory.h
140  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
141  *
142  * PFNs are used to describe any physical page; this means
143  * PFN 0 == physical address 0.
144  */
145 #if defined(__virt_to_phys)
146 #define PHYS_OFFSET	PLAT_PHYS_OFFSET
147 #define PHYS_PFN_OFFSET	((unsigned long)(PHYS_OFFSET >> PAGE_SHIFT))
148 
149 #define virt_to_pfn(kaddr) (__pa(kaddr) >> PAGE_SHIFT)
150 
151 #elif defined(CONFIG_ARM_PATCH_PHYS_VIRT)
152 
153 /*
154  * Constants used to force the right instruction encodings and shifts
155  * so that all we need to do is modify the 8-bit constant field.
156  */
157 #define __PV_BITS_31_24	0x81000000
158 #define __PV_BITS_7_0	0x81
159 
160 extern unsigned long __pv_phys_pfn_offset;
161 extern u64 __pv_offset;
162 extern void fixup_pv_table(const void *, unsigned long);
163 extern const void *__pv_table_begin, *__pv_table_end;
164 
165 #define PHYS_OFFSET	((phys_addr_t)__pv_phys_pfn_offset << PAGE_SHIFT)
166 #define PHYS_PFN_OFFSET	(__pv_phys_pfn_offset)
167 
168 #define virt_to_pfn(kaddr) \
169 	((((unsigned long)(kaddr) - PAGE_OFFSET) >> PAGE_SHIFT) + \
170 	 PHYS_PFN_OFFSET)
171 
172 #define __pv_stub(from,to,instr,type)			\
173 	__asm__("@ __pv_stub\n"				\
174 	"1:	" instr "	%0, %1, %2\n"		\
175 	"	.pushsection .pv_table,\"a\"\n"		\
176 	"	.long	1b\n"				\
177 	"	.popsection\n"				\
178 	: "=r" (to)					\
179 	: "r" (from), "I" (type))
180 
181 #define __pv_stub_mov_hi(t)				\
182 	__asm__ volatile("@ __pv_stub_mov\n"		\
183 	"1:	mov	%R0, %1\n"			\
184 	"	.pushsection .pv_table,\"a\"\n"		\
185 	"	.long	1b\n"				\
186 	"	.popsection\n"				\
187 	: "=r" (t)					\
188 	: "I" (__PV_BITS_7_0))
189 
190 #define __pv_add_carry_stub(x, y)			\
191 	__asm__ volatile("@ __pv_add_carry_stub\n"	\
192 	"1:	adds	%Q0, %1, %2\n"			\
193 	"	adc	%R0, %R0, #0\n"			\
194 	"	.pushsection .pv_table,\"a\"\n"		\
195 	"	.long	1b\n"				\
196 	"	.popsection\n"				\
197 	: "+r" (y)					\
198 	: "r" (x), "I" (__PV_BITS_31_24)		\
199 	: "cc")
200 
201 static inline phys_addr_t __virt_to_phys(unsigned long x)
202 {
203 	phys_addr_t t;
204 
205 	if (sizeof(phys_addr_t) == 4) {
206 		__pv_stub(x, t, "add", __PV_BITS_31_24);
207 	} else {
208 		__pv_stub_mov_hi(t);
209 		__pv_add_carry_stub(x, t);
210 	}
211 	return t;
212 }
213 
214 static inline unsigned long __phys_to_virt(phys_addr_t x)
215 {
216 	unsigned long t;
217 
218 	/*
219 	 * 'unsigned long' cast discard upper word when
220 	 * phys_addr_t is 64 bit, and makes sure that inline
221 	 * assembler expression receives 32 bit argument
222 	 * in place where 'r' 32 bit operand is expected.
223 	 */
224 	__pv_stub((unsigned long) x, t, "sub", __PV_BITS_31_24);
225 	return t;
226 }
227 
228 #else
229 
230 #define PHYS_OFFSET	PLAT_PHYS_OFFSET
231 #define PHYS_PFN_OFFSET	((unsigned long)(PHYS_OFFSET >> PAGE_SHIFT))
232 
233 static inline phys_addr_t __virt_to_phys(unsigned long x)
234 {
235 	return (phys_addr_t)x - PAGE_OFFSET + PHYS_OFFSET;
236 }
237 
238 static inline unsigned long __phys_to_virt(phys_addr_t x)
239 {
240 	return x - PHYS_OFFSET + PAGE_OFFSET;
241 }
242 
243 #define virt_to_pfn(kaddr) \
244 	((((unsigned long)(kaddr) - PAGE_OFFSET) >> PAGE_SHIFT) + \
245 	 PHYS_PFN_OFFSET)
246 
247 #endif
248 
249 /*
250  * These are *only* valid on the kernel direct mapped RAM memory.
251  * Note: Drivers should NOT use these.  They are the wrong
252  * translation for translating DMA addresses.  Use the driver
253  * DMA support - see dma-mapping.h.
254  */
255 #define virt_to_phys virt_to_phys
256 static inline phys_addr_t virt_to_phys(const volatile void *x)
257 {
258 	return __virt_to_phys((unsigned long)(x));
259 }
260 
261 #define phys_to_virt phys_to_virt
262 static inline void *phys_to_virt(phys_addr_t x)
263 {
264 	return (void *)__phys_to_virt(x);
265 }
266 
267 /*
268  * Drivers should NOT use these either.
269  */
270 #define __pa(x)			__virt_to_phys((unsigned long)(x))
271 #define __va(x)			((void *)__phys_to_virt((phys_addr_t)(x)))
272 #define pfn_to_kaddr(pfn)	__va((phys_addr_t)(pfn) << PAGE_SHIFT)
273 
274 extern phys_addr_t (*arch_virt_to_idmap)(unsigned long x);
275 
276 /*
277  * These are for systems that have a hardware interconnect supported alias of
278  * physical memory for idmap purposes.  Most cases should leave these
279  * untouched.
280  */
281 static inline phys_addr_t __virt_to_idmap(unsigned long x)
282 {
283 	if (IS_ENABLED(CONFIG_MMU) && arch_virt_to_idmap)
284 		return arch_virt_to_idmap(x);
285 	else
286 		return __virt_to_phys(x);
287 }
288 
289 #define virt_to_idmap(x)	__virt_to_idmap((unsigned long)(x))
290 
291 /*
292  * Virtual <-> DMA view memory address translations
293  * Again, these are *only* valid on the kernel direct mapped RAM
294  * memory.  Use of these is *deprecated* (and that doesn't mean
295  * use the __ prefixed forms instead.)  See dma-mapping.h.
296  */
297 #ifndef __virt_to_bus
298 #define __virt_to_bus	__virt_to_phys
299 #define __bus_to_virt	__phys_to_virt
300 #define __pfn_to_bus(x)	__pfn_to_phys(x)
301 #define __bus_to_pfn(x)	__phys_to_pfn(x)
302 #endif
303 
304 #ifdef CONFIG_VIRT_TO_BUS
305 #define virt_to_bus virt_to_bus
306 static inline __deprecated unsigned long virt_to_bus(void *x)
307 {
308 	return __virt_to_bus((unsigned long)x);
309 }
310 
311 #define bus_to_virt bus_to_virt
312 static inline __deprecated void *bus_to_virt(unsigned long x)
313 {
314 	return (void *)__bus_to_virt(x);
315 }
316 #endif
317 
318 /*
319  * Conversion between a struct page and a physical address.
320  *
321  *  page_to_pfn(page)	convert a struct page * to a PFN number
322  *  pfn_to_page(pfn)	convert a _valid_ PFN number to struct page *
323  *
324  *  virt_to_page(k)	convert a _valid_ virtual address to struct page *
325  *  virt_addr_valid(k)	indicates whether a virtual address is valid
326  */
327 #define ARCH_PFN_OFFSET		PHYS_PFN_OFFSET
328 
329 #define virt_to_page(kaddr)	pfn_to_page(virt_to_pfn(kaddr))
330 #define virt_addr_valid(kaddr)	(((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory) \
331 					&& pfn_valid(virt_to_pfn(kaddr)))
332 
333 #endif
334 
335 #include <asm-generic/memory_model.h>
336 
337 #endif
338