xref: /openbmc/linux/arch/arm/include/asm/memory.h (revision d2999e1b)
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 #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 #ifndef TASK_SIZE
95 #define TASK_SIZE		(CONFIG_DRAM_SIZE)
96 #endif
97 
98 #ifndef TASK_UNMAPPED_BASE
99 #define TASK_UNMAPPED_BASE	UL(0x00000000)
100 #endif
101 
102 #ifndef END_MEM
103 #define END_MEM     		(UL(CONFIG_DRAM_BASE) + CONFIG_DRAM_SIZE)
104 #endif
105 
106 /*
107  * The module can be at any place in ram in nommu mode.
108  */
109 #define MODULES_END		(END_MEM)
110 #define MODULES_VADDR		PAGE_OFFSET
111 
112 #define XIP_VIRT_ADDR(physaddr)  (physaddr)
113 
114 #endif /* !CONFIG_MMU */
115 
116 /*
117  * We fix the TCM memories max 32 KiB ITCM resp DTCM at these
118  * locations
119  */
120 #ifdef CONFIG_HAVE_TCM
121 #define ITCM_OFFSET	UL(0xfffe0000)
122 #define DTCM_OFFSET	UL(0xfffe8000)
123 #endif
124 
125 /*
126  * Convert a physical address to a Page Frame Number and back
127  */
128 #define	__phys_to_pfn(paddr)	((unsigned long)((paddr) >> PAGE_SHIFT))
129 #define	__pfn_to_phys(pfn)	((phys_addr_t)(pfn) << PAGE_SHIFT)
130 
131 /*
132  * Convert a page to/from a physical address
133  */
134 #define page_to_phys(page)	(__pfn_to_phys(page_to_pfn(page)))
135 #define phys_to_page(phys)	(pfn_to_page(__phys_to_pfn(phys)))
136 
137 /*
138  * Minimum guaranted alignment in pgd_alloc().  The page table pointers passed
139  * around in head.S and proc-*.S are shifted by this amount, in order to
140  * leave spare high bits for systems with physical address extension.  This
141  * does not fully accomodate the 40-bit addressing capability of ARM LPAE, but
142  * gives us about 38-bits or so.
143  */
144 #ifdef CONFIG_ARM_LPAE
145 #define ARCH_PGD_SHIFT		L1_CACHE_SHIFT
146 #else
147 #define ARCH_PGD_SHIFT		0
148 #endif
149 #define ARCH_PGD_MASK		((1 << ARCH_PGD_SHIFT) - 1)
150 
151 /*
152  * PLAT_PHYS_OFFSET is the offset (from zero) of the start of physical
153  * memory.  This is used for XIP and NoMMU kernels, or by kernels which
154  * have their own mach/memory.h.  Assembly code must always use
155  * PLAT_PHYS_OFFSET and not PHYS_OFFSET.
156  */
157 #ifndef PLAT_PHYS_OFFSET
158 #define PLAT_PHYS_OFFSET	UL(CONFIG_PHYS_OFFSET)
159 #endif
160 
161 #ifndef __ASSEMBLY__
162 
163 /*
164  * Physical vs virtual RAM address space conversion.  These are
165  * private definitions which should NOT be used outside memory.h
166  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
167  *
168  * PFNs are used to describe any physical page; this means
169  * PFN 0 == physical address 0.
170  */
171 #if defined(__virt_to_phys)
172 #define PHYS_OFFSET	PLAT_PHYS_OFFSET
173 #define PHYS_PFN_OFFSET	((unsigned long)(PHYS_OFFSET >> PAGE_SHIFT))
174 
175 #define virt_to_pfn(kaddr) (__pa(kaddr) >> PAGE_SHIFT)
176 
177 #elif defined(CONFIG_ARM_PATCH_PHYS_VIRT)
178 
179 /*
180  * Constants used to force the right instruction encodings and shifts
181  * so that all we need to do is modify the 8-bit constant field.
182  */
183 #define __PV_BITS_31_24	0x81000000
184 #define __PV_BITS_7_0	0x81
185 
186 extern unsigned long __pv_phys_pfn_offset;
187 extern u64 __pv_offset;
188 extern void fixup_pv_table(const void *, unsigned long);
189 extern const void *__pv_table_begin, *__pv_table_end;
190 
191 #define PHYS_OFFSET	((phys_addr_t)__pv_phys_pfn_offset << PAGE_SHIFT)
192 #define PHYS_PFN_OFFSET	(__pv_phys_pfn_offset)
193 
194 #define virt_to_pfn(kaddr) \
195 	((((unsigned long)(kaddr) - PAGE_OFFSET) >> PAGE_SHIFT) + \
196 	 PHYS_PFN_OFFSET)
197 
198 #define __pv_stub(from,to,instr,type)			\
199 	__asm__("@ __pv_stub\n"				\
200 	"1:	" instr "	%0, %1, %2\n"		\
201 	"	.pushsection .pv_table,\"a\"\n"		\
202 	"	.long	1b\n"				\
203 	"	.popsection\n"				\
204 	: "=r" (to)					\
205 	: "r" (from), "I" (type))
206 
207 #define __pv_stub_mov_hi(t)				\
208 	__asm__ volatile("@ __pv_stub_mov\n"		\
209 	"1:	mov	%R0, %1\n"			\
210 	"	.pushsection .pv_table,\"a\"\n"		\
211 	"	.long	1b\n"				\
212 	"	.popsection\n"				\
213 	: "=r" (t)					\
214 	: "I" (__PV_BITS_7_0))
215 
216 #define __pv_add_carry_stub(x, y)			\
217 	__asm__ volatile("@ __pv_add_carry_stub\n"	\
218 	"1:	adds	%Q0, %1, %2\n"			\
219 	"	adc	%R0, %R0, #0\n"			\
220 	"	.pushsection .pv_table,\"a\"\n"		\
221 	"	.long	1b\n"				\
222 	"	.popsection\n"				\
223 	: "+r" (y)					\
224 	: "r" (x), "I" (__PV_BITS_31_24)		\
225 	: "cc")
226 
227 static inline phys_addr_t __virt_to_phys(unsigned long x)
228 {
229 	phys_addr_t t;
230 
231 	if (sizeof(phys_addr_t) == 4) {
232 		__pv_stub(x, t, "add", __PV_BITS_31_24);
233 	} else {
234 		__pv_stub_mov_hi(t);
235 		__pv_add_carry_stub(x, t);
236 	}
237 	return t;
238 }
239 
240 static inline unsigned long __phys_to_virt(phys_addr_t x)
241 {
242 	unsigned long t;
243 
244 	/*
245 	 * 'unsigned long' cast discard upper word when
246 	 * phys_addr_t is 64 bit, and makes sure that inline
247 	 * assembler expression receives 32 bit argument
248 	 * in place where 'r' 32 bit operand is expected.
249 	 */
250 	__pv_stub((unsigned long) x, t, "sub", __PV_BITS_31_24);
251 	return t;
252 }
253 
254 #else
255 
256 #define PHYS_OFFSET	PLAT_PHYS_OFFSET
257 #define PHYS_PFN_OFFSET	((unsigned long)(PHYS_OFFSET >> PAGE_SHIFT))
258 
259 static inline phys_addr_t __virt_to_phys(unsigned long x)
260 {
261 	return (phys_addr_t)x - PAGE_OFFSET + PHYS_OFFSET;
262 }
263 
264 static inline unsigned long __phys_to_virt(phys_addr_t x)
265 {
266 	return x - PHYS_OFFSET + PAGE_OFFSET;
267 }
268 
269 #define virt_to_pfn(kaddr) \
270 	((((unsigned long)(kaddr) - PAGE_OFFSET) >> PAGE_SHIFT) + \
271 	 PHYS_PFN_OFFSET)
272 
273 #endif
274 
275 /*
276  * These are *only* valid on the kernel direct mapped RAM memory.
277  * Note: Drivers should NOT use these.  They are the wrong
278  * translation for translating DMA addresses.  Use the driver
279  * DMA support - see dma-mapping.h.
280  */
281 static inline phys_addr_t virt_to_phys(const volatile void *x)
282 {
283 	return __virt_to_phys((unsigned long)(x));
284 }
285 
286 static inline void *phys_to_virt(phys_addr_t x)
287 {
288 	return (void *)__phys_to_virt(x);
289 }
290 
291 /*
292  * Drivers should NOT use these either.
293  */
294 #define __pa(x)			__virt_to_phys((unsigned long)(x))
295 #define __va(x)			((void *)__phys_to_virt((phys_addr_t)(x)))
296 #define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
297 
298 extern phys_addr_t (*arch_virt_to_idmap)(unsigned long x);
299 
300 /*
301  * These are for systems that have a hardware interconnect supported alias of
302  * physical memory for idmap purposes.  Most cases should leave these
303  * untouched.
304  */
305 static inline phys_addr_t __virt_to_idmap(unsigned long x)
306 {
307 	if (arch_virt_to_idmap)
308 		return arch_virt_to_idmap(x);
309 	else
310 		return __virt_to_phys(x);
311 }
312 
313 #define virt_to_idmap(x)	__virt_to_idmap((unsigned long)(x))
314 
315 /*
316  * Virtual <-> DMA view memory address translations
317  * Again, these are *only* valid on the kernel direct mapped RAM
318  * memory.  Use of these is *deprecated* (and that doesn't mean
319  * use the __ prefixed forms instead.)  See dma-mapping.h.
320  */
321 #ifndef __virt_to_bus
322 #define __virt_to_bus	__virt_to_phys
323 #define __bus_to_virt	__phys_to_virt
324 #define __pfn_to_bus(x)	__pfn_to_phys(x)
325 #define __bus_to_pfn(x)	__phys_to_pfn(x)
326 #endif
327 
328 #ifdef CONFIG_VIRT_TO_BUS
329 static inline __deprecated unsigned long virt_to_bus(void *x)
330 {
331 	return __virt_to_bus((unsigned long)x);
332 }
333 
334 static inline __deprecated void *bus_to_virt(unsigned long x)
335 {
336 	return (void *)__bus_to_virt(x);
337 }
338 #endif
339 
340 /*
341  * Conversion between a struct page and a physical address.
342  *
343  *  page_to_pfn(page)	convert a struct page * to a PFN number
344  *  pfn_to_page(pfn)	convert a _valid_ PFN number to struct page *
345  *
346  *  virt_to_page(k)	convert a _valid_ virtual address to struct page *
347  *  virt_addr_valid(k)	indicates whether a virtual address is valid
348  */
349 #define ARCH_PFN_OFFSET		PHYS_PFN_OFFSET
350 
351 #define virt_to_page(kaddr)	pfn_to_page(virt_to_pfn(kaddr))
352 #define virt_addr_valid(kaddr)	(((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory) \
353 					&& pfn_valid(virt_to_pfn(kaddr)))
354 
355 #endif
356 
357 #include <asm-generic/memory_model.h>
358 
359 #endif
360