1 /*
2  * linux/arch/unicore32/include/asm/memory.h
3  *
4  * Code specific to PKUnity SoC and UniCore ISA
5  *
6  * Copyright (C) 2001-2010 GUAN Xue-tao
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  *
12  *  Note: this file should not be included by non-asm/.h files
13  */
14 #ifndef __UNICORE_MEMORY_H__
15 #define __UNICORE_MEMORY_H__
16 
17 #include <linux/compiler.h>
18 #include <linux/const.h>
19 #include <asm/sizes.h>
20 #include <mach/memory.h>
21 
22 /*
23  * Allow for constants defined here to be used from assembly code
24  * by prepending the UL suffix only with actual C code compilation.
25  */
26 #define UL(x) _AC(x, UL)
27 
28 /*
29  * PAGE_OFFSET - the virtual address of the start of the kernel image
30  * TASK_SIZE - the maximum size of a user space task.
31  * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area
32  */
33 #define PAGE_OFFSET		UL(0xC0000000)
34 #define TASK_SIZE		(PAGE_OFFSET - UL(0x41000000))
35 #define TASK_UNMAPPED_BASE	(PAGE_OFFSET / 3)
36 
37 /*
38  * The module space lives between the addresses given by TASK_SIZE
39  * and PAGE_OFFSET - it must be within 32MB of the kernel text.
40  */
41 #define MODULES_VADDR		(PAGE_OFFSET - 16*1024*1024)
42 #if TASK_SIZE > MODULES_VADDR
43 #error Top of user space clashes with start of module space
44 #endif
45 
46 #define MODULES_END		(PAGE_OFFSET)
47 
48 /*
49  * Allow 16MB-aligned ioremap pages
50  */
51 #define IOREMAP_MAX_ORDER	24
52 
53 /*
54  * Physical vs virtual RAM address space conversion.  These are
55  * private definitions which should NOT be used outside memory.h
56  * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
57  */
58 #ifndef __virt_to_phys
59 #define __virt_to_phys(x)	((x) - PAGE_OFFSET + PHYS_OFFSET)
60 #define __phys_to_virt(x)	((x) - PHYS_OFFSET + PAGE_OFFSET)
61 #endif
62 
63 /*
64  * Convert a physical address to a Page Frame Number and back
65  */
66 #define	__phys_to_pfn(paddr)	((paddr) >> PAGE_SHIFT)
67 #define	__pfn_to_phys(pfn)	((pfn) << PAGE_SHIFT)
68 
69 /*
70  * Convert a page to/from a physical address
71  */
72 #define page_to_phys(page)	(__pfn_to_phys(page_to_pfn(page)))
73 #define phys_to_page(phys)	(pfn_to_page(__phys_to_pfn(phys)))
74 
75 #ifndef __ASSEMBLY__
76 
77 #ifndef arch_adjust_zones
78 #define arch_adjust_zones(size, holes) do { } while (0)
79 #endif
80 
81 /*
82  * PFNs are used to describe any physical page; this means
83  * PFN 0 == physical address 0.
84  *
85  * This is the PFN of the first RAM page in the kernel
86  * direct-mapped view.  We assume this is the first page
87  * of RAM in the mem_map as well.
88  */
89 #define PHYS_PFN_OFFSET	(PHYS_OFFSET >> PAGE_SHIFT)
90 
91 /*
92  * Drivers should NOT use these either.
93  */
94 #define __pa(x)			__virt_to_phys((unsigned long)(x))
95 #define __va(x)			((void *)__phys_to_virt((unsigned long)(x)))
96 #define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
97 
98 /*
99  * Conversion between a struct page and a physical address.
100  *
101  * Note: when converting an unknown physical address to a
102  * struct page, the resulting pointer must be validated
103  * using VALID_PAGE().  It must return an invalid struct page
104  * for any physical address not corresponding to a system
105  * RAM address.
106  *
107  *  page_to_pfn(page)	convert a struct page * to a PFN number
108  *  pfn_to_page(pfn)	convert a _valid_ PFN number to struct page *
109  *
110  *  virt_to_page(k)	convert a _valid_ virtual address to struct page *
111  *  virt_addr_valid(k)	indicates whether a virtual address is valid
112  */
113 #define ARCH_PFN_OFFSET		PHYS_PFN_OFFSET
114 
115 #define virt_to_page(kaddr)	pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
116 #define virt_addr_valid(kaddr)	((unsigned long)(kaddr) >= PAGE_OFFSET && \
117 		(unsigned long)(kaddr) < (unsigned long)high_memory)
118 
119 #endif
120 
121 #include <asm-generic/memory_model.h>
122 
123 #endif
124