1 #ifndef _ASM_POWERPC_PAGE_H
2 #define _ASM_POWERPC_PAGE_H
3
4 /*
5 * Copyright (C) 2001,2005 IBM Corporation.
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
11 */
12
13 #ifndef __ASSEMBLY__
14 #include <linux/types.h>
15 #else
16 #include <asm/types.h>
17 #endif
18 #include <asm/asm-compat.h>
19 #include <asm/kdump.h>
20
21 /*
22 * On regular PPC32 page size is 4K (but we support 4K/16K/64K/256K pages
23 * on PPC44x). For PPC64 we support either 4K or 64K software
24 * page size. When using 64K pages however, whether we are really supporting
25 * 64K pages in HW or not is irrelevant to those definitions.
26 */
27 #if defined(CONFIG_PPC_256K_PAGES)
28 #define PAGE_SHIFT 18
29 #elif defined(CONFIG_PPC_64K_PAGES)
30 #define PAGE_SHIFT 16
31 #elif defined(CONFIG_PPC_16K_PAGES)
32 #define PAGE_SHIFT 14
33 #else
34 #define PAGE_SHIFT 12
35 #endif
36
37 #define PAGE_SIZE (ASM_CONST(1) << PAGE_SHIFT)
38
39 /* We do define AT_SYSINFO_EHDR but don't use the gate mechanism */
40 #define __HAVE_ARCH_GATE_AREA 1
41
42 /*
43 * Subtle: (1 << PAGE_SHIFT) is an int, not an unsigned long. So if we
44 * assign PAGE_MASK to a larger type it gets extended the way we want
45 * (i.e. with 1s in the high bits)
46 */
47 #define PAGE_MASK (~((1 << PAGE_SHIFT) - 1))
48
49 /*
50 * KERNELBASE is the virtual address of the start of the kernel, it's often
51 * the same as PAGE_OFFSET, but _might not be_.
52 *
53 * The kdump dump kernel is one example where KERNELBASE != PAGE_OFFSET.
54 *
55 * PAGE_OFFSET is the virtual address of the start of lowmem.
56 *
57 * PHYSICAL_START is the physical address of the start of the kernel.
58 *
59 * MEMORY_START is the physical address of the start of lowmem.
60 *
61 * KERNELBASE, PAGE_OFFSET, and PHYSICAL_START are all configurable on
62 * ppc32 and based on how they are set we determine MEMORY_START.
63 *
64 * For the linear mapping the following equation should be true:
65 * KERNELBASE - PAGE_OFFSET = PHYSICAL_START - MEMORY_START
66 *
67 * Also, KERNELBASE >= PAGE_OFFSET and PHYSICAL_START >= MEMORY_START
68 *
69 * There are two was to determine a physical address from a virtual one:
70 * va = pa + PAGE_OFFSET - MEMORY_START
71 * va = pa + KERNELBASE - PHYSICAL_START
72 *
73 * If you want to know something's offset from the start of the kernel you
74 * should subtract KERNELBASE.
75 *
76 * If you want to test if something's a kernel address, use is_kernel_addr().
77 */
78
79 #define KERNELBASE ASM_CONST(CONFIG_KERNEL_START)
80 #define PAGE_OFFSET ASM_CONST(CONFIG_PAGE_OFFSET)
81 #define LOAD_OFFSET ASM_CONST((CONFIG_KERNEL_START-CONFIG_PHYSICAL_START))
82
83 #if defined(CONFIG_RELOCATABLE)
84 #ifndef __ASSEMBLY__
85
86 extern phys_addr_t memstart_addr;
87 extern phys_addr_t kernstart_addr;
88 #endif
89 #define PHYSICAL_START kernstart_addr
90 #else
91 #define PHYSICAL_START ASM_CONST(CONFIG_PHYSICAL_START)
92 #endif
93
94 #ifdef CONFIG_PPC64
95 #define MEMORY_START 0UL
96 #elif defined(CONFIG_RELOCATABLE)
97 #define MEMORY_START memstart_addr
98 #else
99 #define MEMORY_START (PHYSICAL_START + PAGE_OFFSET - KERNELBASE)
100 #endif
101
102 #ifdef CONFIG_FLATMEM
103 #define ARCH_PFN_OFFSET ((unsigned long)(MEMORY_START >> PAGE_SHIFT))
104 #define pfn_valid(pfn) ((pfn) >= ARCH_PFN_OFFSET && (pfn) < max_mapnr)
105 #endif
106
107 #define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
108 #define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT)
109 #define virt_addr_valid(kaddr) pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
110
111 /*
112 * On Book-E parts we need __va to parse the device tree and we can't
113 * determine MEMORY_START until then. However we can determine PHYSICAL_START
114 * from information at hand (program counter, TLB lookup).
115 *
116 * On non-Book-E PPC64 PAGE_OFFSET and MEMORY_START are constants so use
117 * the other definitions for __va & __pa.
118 */
119 #ifdef CONFIG_BOOKE
120 #define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) - PHYSICAL_START + KERNELBASE))
121 #define __pa(x) ((unsigned long)(x) + PHYSICAL_START - KERNELBASE)
122 #else
123 #define __va(x) ((void *)(unsigned long)((phys_addr_t)(x) + PAGE_OFFSET - MEMORY_START))
124 #define __pa(x) ((unsigned long)(x) - PAGE_OFFSET + MEMORY_START)
125 #endif
126
127 /*
128 * Unfortunately the PLT is in the BSS in the PPC32 ELF ABI,
129 * and needs to be executable. This means the whole heap ends
130 * up being executable.
131 */
132 #define VM_DATA_DEFAULT_FLAGS32 (VM_READ | VM_WRITE | VM_EXEC | \
133 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
134
135 #define VM_DATA_DEFAULT_FLAGS64 (VM_READ | VM_WRITE | \
136 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
137
138 #ifdef __powerpc64__
139 #include <asm/page_64.h>
140 #else
141 #include <asm/page_32.h>
142 #endif
143
144 /* align addr on a size boundary - adjust address up/down if needed */
145 #define _ALIGN_UP(addr,size) (((addr)+((size)-1))&(~((size)-1)))
146 #define _ALIGN_DOWN(addr,size) ((addr)&(~((size)-1)))
147
148 /* align addr on a size boundary - adjust address up if needed */
149 #define _ALIGN(addr,size) _ALIGN_UP(addr,size)
150
151 /*
152 * Don't compare things with KERNELBASE or PAGE_OFFSET to test for
153 * "kernelness", use is_kernel_addr() - it should do what you want.
154 */
155 #ifdef CONFIG_PPC_BOOK3E_64
156 #define is_kernel_addr(x) ((x) >= 0x8000000000000000ul)
157 #else
158 #define is_kernel_addr(x) ((x) >= PAGE_OFFSET)
159 #endif
160
161 #ifndef __ASSEMBLY__
162
163 #undef STRICT_MM_TYPECHECKS
164
165 #ifdef STRICT_MM_TYPECHECKS
166 /* These are used to make use of C type-checking. */
167
168 /* PTE level */
169 typedef struct { pte_basic_t pte; } pte_t;
170 #define pte_val(x) ((x).pte)
171 #define __pte(x) ((pte_t) { (x) })
172
173 /* 64k pages additionally define a bigger "real PTE" type that gathers
174 * the "second half" part of the PTE for pseudo 64k pages
175 */
176 #if defined(CONFIG_PPC_64K_PAGES) && defined(CONFIG_PPC_STD_MMU_64)
177 typedef struct { pte_t pte; unsigned long hidx; } real_pte_t;
178 #else
179 typedef struct { pte_t pte; } real_pte_t;
180 #endif
181
182 /* PMD level */
183 #ifdef CONFIG_PPC64
184 typedef struct { unsigned long pmd; } pmd_t;
185 #define pmd_val(x) ((x).pmd)
186 #define __pmd(x) ((pmd_t) { (x) })
187
188 /* PUD level exusts only on 4k pages */
189 #ifndef CONFIG_PPC_64K_PAGES
190 typedef struct { unsigned long pud; } pud_t;
191 #define pud_val(x) ((x).pud)
192 #define __pud(x) ((pud_t) { (x) })
193 #endif /* !CONFIG_PPC_64K_PAGES */
194 #endif /* CONFIG_PPC64 */
195
196 /* PGD level */
197 typedef struct { unsigned long pgd; } pgd_t;
198 #define pgd_val(x) ((x).pgd)
199 #define __pgd(x) ((pgd_t) { (x) })
200
201 /* Page protection bits */
202 typedef struct { unsigned long pgprot; } pgprot_t;
203 #define pgprot_val(x) ((x).pgprot)
204 #define __pgprot(x) ((pgprot_t) { (x) })
205
206 #else
207
208 /*
209 * .. while these make it easier on the compiler
210 */
211
212 typedef pte_basic_t pte_t;
213 #define pte_val(x) (x)
214 #define __pte(x) (x)
215
216 #if defined(CONFIG_PPC_64K_PAGES) && defined(CONFIG_PPC_STD_MMU_64)
217 typedef struct { pte_t pte; unsigned long hidx; } real_pte_t;
218 #else
219 typedef pte_t real_pte_t;
220 #endif
221
222
223 #ifdef CONFIG_PPC64
224 typedef unsigned long pmd_t;
225 #define pmd_val(x) (x)
226 #define __pmd(x) (x)
227
228 #ifndef CONFIG_PPC_64K_PAGES
229 typedef unsigned long pud_t;
230 #define pud_val(x) (x)
231 #define __pud(x) (x)
232 #endif /* !CONFIG_PPC_64K_PAGES */
233 #endif /* CONFIG_PPC64 */
234
235 typedef unsigned long pgd_t;
236 #define pgd_val(x) (x)
237 #define pgprot_val(x) (x)
238
239 typedef unsigned long pgprot_t;
240 #define __pgd(x) (x)
241 #define __pgprot(x) (x)
242
243 #endif
244
245 typedef struct { signed long pd; } hugepd_t;
246 #define HUGEPD_SHIFT_MASK 0x3f
247
248 #ifdef CONFIG_HUGETLB_PAGE
hugepd_ok(hugepd_t hpd)249 static inline int hugepd_ok(hugepd_t hpd)
250 {
251 return (hpd.pd > 0);
252 }
253
254 #define is_hugepd(pdep) (hugepd_ok(*((hugepd_t *)(pdep))))
255 #else /* CONFIG_HUGETLB_PAGE */
256 #define is_hugepd(pdep) 0
257 #endif /* CONFIG_HUGETLB_PAGE */
258
259 struct page;
260 extern void clear_user_page(void *page, unsigned long vaddr, struct page *pg);
261 extern void copy_user_page(void *to, void *from, unsigned long vaddr,
262 struct page *p);
263 extern int page_is_ram(unsigned long pfn);
264
265 #ifdef CONFIG_PPC_SMLPAR
266 void arch_free_page(struct page *page, int order);
267 #define HAVE_ARCH_FREE_PAGE
268 #endif
269
270 struct vm_area_struct;
271
272 typedef struct page *pgtable_t;
273
274 #include <asm-generic/memory_model.h>
275 #endif /* __ASSEMBLY__ */
276
277 #endif /* _ASM_POWERPC_PAGE_H */
278