xref: /openbmc/linux/arch/arm/include/asm/memory.h (revision 12eb4683)
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 #ifdef CONFIG_MMU
34 
35 /*
36  * PAGE_OFFSET - the virtual address of the start of the kernel image
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 PAGE_OFFSET		UL(CONFIG_PAGE_OFFSET)
41 #define TASK_SIZE		(UL(CONFIG_PAGE_OFFSET) - UL(SZ_16M))
42 #define TASK_UNMAPPED_BASE	ALIGN(TASK_SIZE / 3, SZ_16M)
43 
44 /*
45  * The maximum size of a 26-bit user space task.
46  */
47 #define TASK_SIZE_26		(UL(1) << 26)
48 
49 /*
50  * The module space lives between the addresses given by TASK_SIZE
51  * and PAGE_OFFSET - it must be within 32MB of the kernel text.
52  */
53 #ifndef CONFIG_THUMB2_KERNEL
54 #define MODULES_VADDR		(PAGE_OFFSET - SZ_16M)
55 #else
56 /* smaller range for Thumb-2 symbols relocation (2^24)*/
57 #define MODULES_VADDR		(PAGE_OFFSET - SZ_8M)
58 #endif
59 
60 #if TASK_SIZE > MODULES_VADDR
61 #error Top of user space clashes with start of module space
62 #endif
63 
64 /*
65  * The highmem pkmap virtual space shares the end of the module area.
66  */
67 #ifdef CONFIG_HIGHMEM
68 #define MODULES_END		(PAGE_OFFSET - PMD_SIZE)
69 #else
70 #define MODULES_END		(PAGE_OFFSET)
71 #endif
72 
73 /*
74  * The XIP kernel gets mapped at the bottom of the module vm area.
75  * Since we use sections to map it, this macro replaces the physical address
76  * with its virtual address while keeping offset from the base section.
77  */
78 #define XIP_VIRT_ADDR(physaddr)  (MODULES_VADDR + ((physaddr) & 0x000fffff))
79 
80 /*
81  * Allow 16MB-aligned ioremap pages
82  */
83 #define IOREMAP_MAX_ORDER	24
84 
85 #define CONSISTENT_END		(0xffe00000UL)
86 
87 #else /* CONFIG_MMU */
88 
89 /*
90  * The limitation of user task size can grow up to the end of free ram region.
91  * It is difficult to define and perhaps will never meet the original meaning
92  * of this define that was meant to.
93  * Fortunately, there is no reference for this in noMMU mode, for now.
94  */
95 #ifndef TASK_SIZE
96 #define TASK_SIZE		(CONFIG_DRAM_SIZE)
97 #endif
98 
99 #ifndef TASK_UNMAPPED_BASE
100 #define TASK_UNMAPPED_BASE	UL(0x00000000)
101 #endif
102 
103 #ifndef END_MEM
104 #define END_MEM     		(UL(CONFIG_DRAM_BASE) + CONFIG_DRAM_SIZE)
105 #endif
106 
107 #ifndef PAGE_OFFSET
108 #define PAGE_OFFSET		PLAT_PHYS_OFFSET
109 #endif
110 
111 /*
112  * The module can be at any place in ram in nommu mode.
113  */
114 #define MODULES_END		(END_MEM)
115 #define MODULES_VADDR		PAGE_OFFSET
116 
117 #define XIP_VIRT_ADDR(physaddr)  (physaddr)
118 
119 #endif /* !CONFIG_MMU */
120 
121 /*
122  * We fix the TCM memories max 32 KiB ITCM resp DTCM at these
123  * locations
124  */
125 #ifdef CONFIG_HAVE_TCM
126 #define ITCM_OFFSET	UL(0xfffe0000)
127 #define DTCM_OFFSET	UL(0xfffe8000)
128 #endif
129 
130 /*
131  * Convert a physical address to a Page Frame Number and back
132  */
133 #define	__phys_to_pfn(paddr)	((unsigned long)((paddr) >> PAGE_SHIFT))
134 #define	__pfn_to_phys(pfn)	((phys_addr_t)(pfn) << PAGE_SHIFT)
135 
136 /*
137  * Convert a page to/from a physical address
138  */
139 #define page_to_phys(page)	(__pfn_to_phys(page_to_pfn(page)))
140 #define phys_to_page(phys)	(pfn_to_page(__phys_to_pfn(phys)))
141 
142 /*
143  * Minimum guaranted alignment in pgd_alloc().  The page table pointers passed
144  * around in head.S and proc-*.S are shifted by this amount, in order to
145  * leave spare high bits for systems with physical address extension.  This
146  * does not fully accomodate the 40-bit addressing capability of ARM LPAE, but
147  * gives us about 38-bits or so.
148  */
149 #ifdef CONFIG_ARM_LPAE
150 #define ARCH_PGD_SHIFT		L1_CACHE_SHIFT
151 #else
152 #define ARCH_PGD_SHIFT		0
153 #endif
154 #define ARCH_PGD_MASK		((1 << ARCH_PGD_SHIFT) - 1)
155 
156 /*
157  * PLAT_PHYS_OFFSET is the offset (from zero) of the start of physical
158  * memory.  This is used for XIP and NoMMU kernels, or by kernels which
159  * have their own mach/memory.h.  Assembly code must always use
160  * PLAT_PHYS_OFFSET and not PHYS_OFFSET.
161  */
162 #ifndef PLAT_PHYS_OFFSET
163 #define PLAT_PHYS_OFFSET	UL(CONFIG_PHYS_OFFSET)
164 #endif
165 
166 #ifndef __ASSEMBLY__
167 
168 /*
169  * Physical vs virtual RAM address space conversion.  These are
170  * private definitions which should NOT be used outside memory.h
171  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
172  */
173 #ifndef __virt_to_phys
174 #ifdef CONFIG_ARM_PATCH_PHYS_VIRT
175 
176 /*
177  * Constants used to force the right instruction encodings and shifts
178  * so that all we need to do is modify the 8-bit constant field.
179  */
180 #define __PV_BITS_31_24	0x81000000
181 #define __PV_BITS_7_0	0x81
182 
183 extern u64 __pv_phys_offset;
184 extern u64 __pv_offset;
185 extern void fixup_pv_table(const void *, unsigned long);
186 extern const void *__pv_table_begin, *__pv_table_end;
187 
188 #define PHYS_OFFSET __pv_phys_offset
189 
190 #define __pv_stub(from,to,instr,type)			\
191 	__asm__("@ __pv_stub\n"				\
192 	"1:	" instr "	%0, %1, %2\n"		\
193 	"	.pushsection .pv_table,\"a\"\n"		\
194 	"	.long	1b\n"				\
195 	"	.popsection\n"				\
196 	: "=r" (to)					\
197 	: "r" (from), "I" (type))
198 
199 #define __pv_stub_mov_hi(t)				\
200 	__asm__ volatile("@ __pv_stub_mov\n"		\
201 	"1:	mov	%R0, %1\n"			\
202 	"	.pushsection .pv_table,\"a\"\n"		\
203 	"	.long	1b\n"				\
204 	"	.popsection\n"				\
205 	: "=r" (t)					\
206 	: "I" (__PV_BITS_7_0))
207 
208 #define __pv_add_carry_stub(x, y)			\
209 	__asm__ volatile("@ __pv_add_carry_stub\n"	\
210 	"1:	adds	%Q0, %1, %2\n"			\
211 	"	adc	%R0, %R0, #0\n"			\
212 	"	.pushsection .pv_table,\"a\"\n"		\
213 	"	.long	1b\n"				\
214 	"	.popsection\n"				\
215 	: "+r" (y)					\
216 	: "r" (x), "I" (__PV_BITS_31_24)		\
217 	: "cc")
218 
219 static inline phys_addr_t __virt_to_phys(unsigned long x)
220 {
221 	phys_addr_t t;
222 
223 	if (sizeof(phys_addr_t) == 4) {
224 		__pv_stub(x, t, "add", __PV_BITS_31_24);
225 	} else {
226 		__pv_stub_mov_hi(t);
227 		__pv_add_carry_stub(x, t);
228 	}
229 	return t;
230 }
231 
232 static inline unsigned long __phys_to_virt(phys_addr_t x)
233 {
234 	unsigned long t;
235 
236 	/*
237 	 * 'unsigned long' cast discard upper word when
238 	 * phys_addr_t is 64 bit, and makes sure that inline
239 	 * assembler expression receives 32 bit argument
240 	 * in place where 'r' 32 bit operand is expected.
241 	 */
242 	__pv_stub((unsigned long) x, t, "sub", __PV_BITS_31_24);
243 	return t;
244 }
245 
246 #else
247 
248 #define PHYS_OFFSET	PLAT_PHYS_OFFSET
249 
250 static inline phys_addr_t __virt_to_phys(unsigned long x)
251 {
252 	return (phys_addr_t)x - PAGE_OFFSET + PHYS_OFFSET;
253 }
254 
255 static inline unsigned long __phys_to_virt(phys_addr_t x)
256 {
257 	return x - PHYS_OFFSET + PAGE_OFFSET;
258 }
259 
260 #endif
261 #endif
262 
263 /*
264  * PFNs are used to describe any physical page; this means
265  * PFN 0 == physical address 0.
266  *
267  * This is the PFN of the first RAM page in the kernel
268  * direct-mapped view.  We assume this is the first page
269  * of RAM in the mem_map as well.
270  */
271 #define PHYS_PFN_OFFSET	((unsigned long)(PHYS_OFFSET >> PAGE_SHIFT))
272 
273 /*
274  * These are *only* valid on the kernel direct mapped RAM memory.
275  * Note: Drivers should NOT use these.  They are the wrong
276  * translation for translating DMA addresses.  Use the driver
277  * DMA support - see dma-mapping.h.
278  */
279 static inline phys_addr_t virt_to_phys(const volatile void *x)
280 {
281 	return __virt_to_phys((unsigned long)(x));
282 }
283 
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 static inline __deprecated unsigned long virt_to_bus(void *x)
328 {
329 	return __virt_to_bus((unsigned long)x);
330 }
331 
332 static inline __deprecated void *bus_to_virt(unsigned long x)
333 {
334 	return (void *)__bus_to_virt(x);
335 }
336 #endif
337 
338 /*
339  * Conversion between a struct page and a physical address.
340  *
341  *  page_to_pfn(page)	convert a struct page * to a PFN number
342  *  pfn_to_page(pfn)	convert a _valid_ PFN number to struct page *
343  *
344  *  virt_to_page(k)	convert a _valid_ virtual address to struct page *
345  *  virt_addr_valid(k)	indicates whether a virtual address is valid
346  */
347 #define ARCH_PFN_OFFSET		PHYS_PFN_OFFSET
348 
349 #define virt_to_page(kaddr)	pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
350 #define virt_addr_valid(kaddr)	((unsigned long)(kaddr) >= PAGE_OFFSET && (unsigned long)(kaddr) < (unsigned long)high_memory)
351 
352 #endif
353 
354 #include <asm-generic/memory_model.h>
355 
356 #endif
357