xref: /linux/arch/arm/include/asm/memory.h (revision c0c914eca7f251c70facc37dfebeaf176601918d)
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 #if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
80 /*
81  * Allow 16MB-aligned ioremap pages
82  */
83 #define IOREMAP_MAX_ORDER	24
84 #endif
85 
86 #else /* CONFIG_MMU */
87 
88 /*
89  * The limitation of user task size can grow up to the end of free ram region.
90  * It is difficult to define and perhaps will never meet the original meaning
91  * of this define that was meant to.
92  * Fortunately, there is no reference for this in noMMU mode, for now.
93  */
94 #define TASK_SIZE		UL(0xffffffff)
95 
96 #ifndef TASK_UNMAPPED_BASE
97 #define TASK_UNMAPPED_BASE	UL(0x00000000)
98 #endif
99 
100 #ifndef END_MEM
101 #define END_MEM     		(UL(CONFIG_DRAM_BASE) + CONFIG_DRAM_SIZE)
102 #endif
103 
104 /*
105  * The module can be at any place in ram in nommu mode.
106  */
107 #define MODULES_END		(END_MEM)
108 #define MODULES_VADDR		PAGE_OFFSET
109 
110 #define XIP_VIRT_ADDR(physaddr)  (physaddr)
111 
112 #endif /* !CONFIG_MMU */
113 
114 /*
115  * We fix the TCM memories max 32 KiB ITCM resp DTCM at these
116  * locations
117  */
118 #ifdef CONFIG_HAVE_TCM
119 #define ITCM_OFFSET	UL(0xfffe0000)
120 #define DTCM_OFFSET	UL(0xfffe8000)
121 #endif
122 
123 /*
124  * Convert a page to/from a physical address
125  */
126 #define page_to_phys(page)	(__pfn_to_phys(page_to_pfn(page)))
127 #define phys_to_page(phys)	(pfn_to_page(__phys_to_pfn(phys)))
128 
129 /*
130  * PLAT_PHYS_OFFSET is the offset (from zero) of the start of physical
131  * memory.  This is used for XIP and NoMMU kernels, and on platforms that don't
132  * have CONFIG_ARM_PATCH_PHYS_VIRT. Assembly code must always use
133  * PLAT_PHYS_OFFSET and not PHYS_OFFSET.
134  */
135 #define PLAT_PHYS_OFFSET	UL(CONFIG_PHYS_OFFSET)
136 
137 #ifndef __ASSEMBLY__
138 
139 /*
140  * Physical vs virtual RAM address space conversion.  These are
141  * private definitions which should NOT be used outside memory.h
142  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
143  *
144  * PFNs are used to describe any physical page; this means
145  * PFN 0 == physical address 0.
146  */
147 #if defined(__virt_to_phys)
148 #define PHYS_OFFSET	PLAT_PHYS_OFFSET
149 #define PHYS_PFN_OFFSET	((unsigned long)(PHYS_OFFSET >> PAGE_SHIFT))
150 
151 #define virt_to_pfn(kaddr) (__pa(kaddr) >> PAGE_SHIFT)
152 
153 #elif defined(CONFIG_ARM_PATCH_PHYS_VIRT)
154 
155 /*
156  * Constants used to force the right instruction encodings and shifts
157  * so that all we need to do is modify the 8-bit constant field.
158  */
159 #define __PV_BITS_31_24	0x81000000
160 #define __PV_BITS_7_0	0x81
161 
162 extern unsigned long __pv_phys_pfn_offset;
163 extern u64 __pv_offset;
164 extern void fixup_pv_table(const void *, unsigned long);
165 extern const void *__pv_table_begin, *__pv_table_end;
166 
167 #define PHYS_OFFSET	((phys_addr_t)__pv_phys_pfn_offset << PAGE_SHIFT)
168 #define PHYS_PFN_OFFSET	(__pv_phys_pfn_offset)
169 
170 #define virt_to_pfn(kaddr) \
171 	((((unsigned long)(kaddr) - PAGE_OFFSET) >> PAGE_SHIFT) + \
172 	 PHYS_PFN_OFFSET)
173 
174 #define __pv_stub(from,to,instr,type)			\
175 	__asm__("@ __pv_stub\n"				\
176 	"1:	" instr "	%0, %1, %2\n"		\
177 	"	.pushsection .pv_table,\"a\"\n"		\
178 	"	.long	1b\n"				\
179 	"	.popsection\n"				\
180 	: "=r" (to)					\
181 	: "r" (from), "I" (type))
182 
183 #define __pv_stub_mov_hi(t)				\
184 	__asm__ volatile("@ __pv_stub_mov\n"		\
185 	"1:	mov	%R0, %1\n"			\
186 	"	.pushsection .pv_table,\"a\"\n"		\
187 	"	.long	1b\n"				\
188 	"	.popsection\n"				\
189 	: "=r" (t)					\
190 	: "I" (__PV_BITS_7_0))
191 
192 #define __pv_add_carry_stub(x, y)			\
193 	__asm__ volatile("@ __pv_add_carry_stub\n"	\
194 	"1:	adds	%Q0, %1, %2\n"			\
195 	"	adc	%R0, %R0, #0\n"			\
196 	"	.pushsection .pv_table,\"a\"\n"		\
197 	"	.long	1b\n"				\
198 	"	.popsection\n"				\
199 	: "+r" (y)					\
200 	: "r" (x), "I" (__PV_BITS_31_24)		\
201 	: "cc")
202 
203 static inline phys_addr_t __virt_to_phys(unsigned long x)
204 {
205 	phys_addr_t t;
206 
207 	if (sizeof(phys_addr_t) == 4) {
208 		__pv_stub(x, t, "add", __PV_BITS_31_24);
209 	} else {
210 		__pv_stub_mov_hi(t);
211 		__pv_add_carry_stub(x, t);
212 	}
213 	return t;
214 }
215 
216 static inline unsigned long __phys_to_virt(phys_addr_t x)
217 {
218 	unsigned long t;
219 
220 	/*
221 	 * 'unsigned long' cast discard upper word when
222 	 * phys_addr_t is 64 bit, and makes sure that inline
223 	 * assembler expression receives 32 bit argument
224 	 * in place where 'r' 32 bit operand is expected.
225 	 */
226 	__pv_stub((unsigned long) x, t, "sub", __PV_BITS_31_24);
227 	return t;
228 }
229 
230 #else
231 
232 #define PHYS_OFFSET	PLAT_PHYS_OFFSET
233 #define PHYS_PFN_OFFSET	((unsigned long)(PHYS_OFFSET >> PAGE_SHIFT))
234 
235 static inline phys_addr_t __virt_to_phys(unsigned long x)
236 {
237 	return (phys_addr_t)x - PAGE_OFFSET + PHYS_OFFSET;
238 }
239 
240 static inline unsigned long __phys_to_virt(phys_addr_t x)
241 {
242 	return x - PHYS_OFFSET + PAGE_OFFSET;
243 }
244 
245 #define virt_to_pfn(kaddr) \
246 	((((unsigned long)(kaddr) - PAGE_OFFSET) >> PAGE_SHIFT) + \
247 	 PHYS_PFN_OFFSET)
248 
249 #endif
250 
251 /*
252  * These are *only* valid on the kernel direct mapped RAM memory.
253  * Note: Drivers should NOT use these.  They are the wrong
254  * translation for translating DMA addresses.  Use the driver
255  * DMA support - see dma-mapping.h.
256  */
257 #define virt_to_phys virt_to_phys
258 static inline phys_addr_t virt_to_phys(const volatile void *x)
259 {
260 	return __virt_to_phys((unsigned long)(x));
261 }
262 
263 #define phys_to_virt phys_to_virt
264 static inline void *phys_to_virt(phys_addr_t x)
265 {
266 	return (void *)__phys_to_virt(x);
267 }
268 
269 /*
270  * Drivers should NOT use these either.
271  */
272 #define __pa(x)			__virt_to_phys((unsigned long)(x))
273 #define __va(x)			((void *)__phys_to_virt((phys_addr_t)(x)))
274 #define pfn_to_kaddr(pfn)	__va((phys_addr_t)(pfn) << PAGE_SHIFT)
275 
276 extern phys_addr_t (*arch_virt_to_idmap)(unsigned long x);
277 
278 /*
279  * These are for systems that have a hardware interconnect supported alias of
280  * physical memory for idmap purposes.  Most cases should leave these
281  * untouched.
282  */
283 static inline phys_addr_t __virt_to_idmap(unsigned long x)
284 {
285 	if (IS_ENABLED(CONFIG_MMU) && arch_virt_to_idmap)
286 		return arch_virt_to_idmap(x);
287 	else
288 		return __virt_to_phys(x);
289 }
290 
291 #define virt_to_idmap(x)	__virt_to_idmap((unsigned long)(x))
292 
293 /*
294  * Virtual <-> DMA view memory address translations
295  * Again, these are *only* valid on the kernel direct mapped RAM
296  * memory.  Use of these is *deprecated* (and that doesn't mean
297  * use the __ prefixed forms instead.)  See dma-mapping.h.
298  */
299 #ifndef __virt_to_bus
300 #define __virt_to_bus	__virt_to_phys
301 #define __bus_to_virt	__phys_to_virt
302 #define __pfn_to_bus(x)	__pfn_to_phys(x)
303 #define __bus_to_pfn(x)	__phys_to_pfn(x)
304 #endif
305 
306 #ifdef CONFIG_VIRT_TO_BUS
307 #define virt_to_bus virt_to_bus
308 static inline __deprecated unsigned long virt_to_bus(void *x)
309 {
310 	return __virt_to_bus((unsigned long)x);
311 }
312 
313 #define bus_to_virt bus_to_virt
314 static inline __deprecated void *bus_to_virt(unsigned long x)
315 {
316 	return (void *)__bus_to_virt(x);
317 }
318 #endif
319 
320 /*
321  * Conversion between a struct page and a physical address.
322  *
323  *  page_to_pfn(page)	convert a struct page * to a PFN number
324  *  pfn_to_page(pfn)	convert a _valid_ PFN number to struct page *
325  *
326  *  virt_to_page(k)	convert a _valid_ virtual address to struct page *
327  *  virt_addr_valid(k)	indicates whether a virtual address is valid
328  */
329 #define ARCH_PFN_OFFSET		PHYS_PFN_OFFSET
330 
331 #define virt_to_page(kaddr)	pfn_to_page(virt_to_pfn(kaddr))
332 #define virt_addr_valid(kaddr)	(((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory) \
333 					&& pfn_valid(virt_to_pfn(kaddr)))
334 
335 #endif
336 
337 #include <asm-generic/memory_model.h>
338 
339 #endif
340