xref: /openbmc/linux/arch/arm/include/asm/memory.h (revision 4f3db074)
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 #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 physical address to a Page Frame Number and back
125  */
126 #define	__phys_to_pfn(paddr)	((unsigned long)((paddr) >> PAGE_SHIFT))
127 #define	__pfn_to_phys(pfn)	((phys_addr_t)(pfn) << PAGE_SHIFT)
128 
129 /*
130  * Convert a page to/from a physical address
131  */
132 #define page_to_phys(page)	(__pfn_to_phys(page_to_pfn(page)))
133 #define phys_to_page(phys)	(pfn_to_page(__phys_to_pfn(phys)))
134 
135 /*
136  * Minimum guaranted alignment in pgd_alloc().  The page table pointers passed
137  * around in head.S and proc-*.S are shifted by this amount, in order to
138  * leave spare high bits for systems with physical address extension.  This
139  * does not fully accomodate the 40-bit addressing capability of ARM LPAE, but
140  * gives us about 38-bits or so.
141  */
142 #ifdef CONFIG_ARM_LPAE
143 #define ARCH_PGD_SHIFT		L1_CACHE_SHIFT
144 #else
145 #define ARCH_PGD_SHIFT		0
146 #endif
147 #define ARCH_PGD_MASK		((1 << ARCH_PGD_SHIFT) - 1)
148 
149 /*
150  * PLAT_PHYS_OFFSET is the offset (from zero) of the start of physical
151  * memory.  This is used for XIP and NoMMU kernels, and on platforms that don't
152  * have CONFIG_ARM_PATCH_PHYS_VIRT. Assembly code must always use
153  * PLAT_PHYS_OFFSET and not PHYS_OFFSET.
154  */
155 #define PLAT_PHYS_OFFSET	UL(CONFIG_PHYS_OFFSET)
156 
157 #ifndef __ASSEMBLY__
158 
159 /*
160  * Physical vs virtual RAM address space conversion.  These are
161  * private definitions which should NOT be used outside memory.h
162  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
163  *
164  * PFNs are used to describe any physical page; this means
165  * PFN 0 == physical address 0.
166  */
167 #if defined(__virt_to_phys)
168 #define PHYS_OFFSET	PLAT_PHYS_OFFSET
169 #define PHYS_PFN_OFFSET	((unsigned long)(PHYS_OFFSET >> PAGE_SHIFT))
170 
171 #define virt_to_pfn(kaddr) (__pa(kaddr) >> PAGE_SHIFT)
172 
173 #elif defined(CONFIG_ARM_PATCH_PHYS_VIRT)
174 
175 /*
176  * Constants used to force the right instruction encodings and shifts
177  * so that all we need to do is modify the 8-bit constant field.
178  */
179 #define __PV_BITS_31_24	0x81000000
180 #define __PV_BITS_7_0	0x81
181 
182 extern unsigned long __pv_phys_pfn_offset;
183 extern u64 __pv_offset;
184 extern void fixup_pv_table(const void *, unsigned long);
185 extern const void *__pv_table_begin, *__pv_table_end;
186 
187 #define PHYS_OFFSET	((phys_addr_t)__pv_phys_pfn_offset << PAGE_SHIFT)
188 #define PHYS_PFN_OFFSET	(__pv_phys_pfn_offset)
189 
190 #define virt_to_pfn(kaddr) \
191 	((((unsigned long)(kaddr) - PAGE_OFFSET) >> PAGE_SHIFT) + \
192 	 PHYS_PFN_OFFSET)
193 
194 #define __pv_stub(from,to,instr,type)			\
195 	__asm__("@ __pv_stub\n"				\
196 	"1:	" instr "	%0, %1, %2\n"		\
197 	"	.pushsection .pv_table,\"a\"\n"		\
198 	"	.long	1b\n"				\
199 	"	.popsection\n"				\
200 	: "=r" (to)					\
201 	: "r" (from), "I" (type))
202 
203 #define __pv_stub_mov_hi(t)				\
204 	__asm__ volatile("@ __pv_stub_mov\n"		\
205 	"1:	mov	%R0, %1\n"			\
206 	"	.pushsection .pv_table,\"a\"\n"		\
207 	"	.long	1b\n"				\
208 	"	.popsection\n"				\
209 	: "=r" (t)					\
210 	: "I" (__PV_BITS_7_0))
211 
212 #define __pv_add_carry_stub(x, y)			\
213 	__asm__ volatile("@ __pv_add_carry_stub\n"	\
214 	"1:	adds	%Q0, %1, %2\n"			\
215 	"	adc	%R0, %R0, #0\n"			\
216 	"	.pushsection .pv_table,\"a\"\n"		\
217 	"	.long	1b\n"				\
218 	"	.popsection\n"				\
219 	: "+r" (y)					\
220 	: "r" (x), "I" (__PV_BITS_31_24)		\
221 	: "cc")
222 
223 static inline phys_addr_t __virt_to_phys(unsigned long x)
224 {
225 	phys_addr_t t;
226 
227 	if (sizeof(phys_addr_t) == 4) {
228 		__pv_stub(x, t, "add", __PV_BITS_31_24);
229 	} else {
230 		__pv_stub_mov_hi(t);
231 		__pv_add_carry_stub(x, t);
232 	}
233 	return t;
234 }
235 
236 static inline unsigned long __phys_to_virt(phys_addr_t x)
237 {
238 	unsigned long t;
239 
240 	/*
241 	 * 'unsigned long' cast discard upper word when
242 	 * phys_addr_t is 64 bit, and makes sure that inline
243 	 * assembler expression receives 32 bit argument
244 	 * in place where 'r' 32 bit operand is expected.
245 	 */
246 	__pv_stub((unsigned long) x, t, "sub", __PV_BITS_31_24);
247 	return t;
248 }
249 
250 #else
251 
252 #define PHYS_OFFSET	PLAT_PHYS_OFFSET
253 #define PHYS_PFN_OFFSET	((unsigned long)(PHYS_OFFSET >> PAGE_SHIFT))
254 
255 static inline phys_addr_t __virt_to_phys(unsigned long x)
256 {
257 	return (phys_addr_t)x - PAGE_OFFSET + PHYS_OFFSET;
258 }
259 
260 static inline unsigned long __phys_to_virt(phys_addr_t x)
261 {
262 	return x - PHYS_OFFSET + PAGE_OFFSET;
263 }
264 
265 #define virt_to_pfn(kaddr) \
266 	((((unsigned long)(kaddr) - PAGE_OFFSET) >> PAGE_SHIFT) + \
267 	 PHYS_PFN_OFFSET)
268 
269 #endif
270 
271 /*
272  * These are *only* valid on the kernel direct mapped RAM memory.
273  * Note: Drivers should NOT use these.  They are the wrong
274  * translation for translating DMA addresses.  Use the driver
275  * DMA support - see dma-mapping.h.
276  */
277 #define virt_to_phys virt_to_phys
278 static inline phys_addr_t virt_to_phys(const volatile void *x)
279 {
280 	return __virt_to_phys((unsigned long)(x));
281 }
282 
283 #define phys_to_virt phys_to_virt
284 static inline void *phys_to_virt(phys_addr_t x)
285 {
286 	return (void *)__phys_to_virt(x);
287 }
288 
289 /*
290  * Drivers should NOT use these either.
291  */
292 #define __pa(x)			__virt_to_phys((unsigned long)(x))
293 #define __va(x)			((void *)__phys_to_virt((phys_addr_t)(x)))
294 #define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
295 
296 extern phys_addr_t (*arch_virt_to_idmap)(unsigned long x);
297 
298 /*
299  * These are for systems that have a hardware interconnect supported alias of
300  * physical memory for idmap purposes.  Most cases should leave these
301  * untouched.
302  */
303 static inline phys_addr_t __virt_to_idmap(unsigned long x)
304 {
305 	if (arch_virt_to_idmap)
306 		return arch_virt_to_idmap(x);
307 	else
308 		return __virt_to_phys(x);
309 }
310 
311 #define virt_to_idmap(x)	__virt_to_idmap((unsigned long)(x))
312 
313 /*
314  * Virtual <-> DMA view memory address translations
315  * Again, these are *only* valid on the kernel direct mapped RAM
316  * memory.  Use of these is *deprecated* (and that doesn't mean
317  * use the __ prefixed forms instead.)  See dma-mapping.h.
318  */
319 #ifndef __virt_to_bus
320 #define __virt_to_bus	__virt_to_phys
321 #define __bus_to_virt	__phys_to_virt
322 #define __pfn_to_bus(x)	__pfn_to_phys(x)
323 #define __bus_to_pfn(x)	__phys_to_pfn(x)
324 #endif
325 
326 #ifdef CONFIG_VIRT_TO_BUS
327 #define virt_to_bus virt_to_bus
328 static inline __deprecated unsigned long virt_to_bus(void *x)
329 {
330 	return __virt_to_bus((unsigned long)x);
331 }
332 
333 #define bus_to_virt bus_to_virt
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