xref: /linux/arch/mips/include/asm/page.h (revision b6ebbac51bedf9e98e837688bc838f400196da5e)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 1994 - 1999, 2000, 03 Ralf Baechle
7  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
8  */
9 #ifndef _ASM_PAGE_H
10 #define _ASM_PAGE_H
11 
12 #include <spaces.h>
13 #include <linux/const.h>
14 #include <linux/kernel.h>
15 #include <asm/mipsregs.h>
16 
17 /*
18  * PAGE_SHIFT determines the page size
19  */
20 #ifdef CONFIG_PAGE_SIZE_4KB
21 #define PAGE_SHIFT	12
22 #endif
23 #ifdef CONFIG_PAGE_SIZE_8KB
24 #define PAGE_SHIFT	13
25 #endif
26 #ifdef CONFIG_PAGE_SIZE_16KB
27 #define PAGE_SHIFT	14
28 #endif
29 #ifdef CONFIG_PAGE_SIZE_32KB
30 #define PAGE_SHIFT	15
31 #endif
32 #ifdef CONFIG_PAGE_SIZE_64KB
33 #define PAGE_SHIFT	16
34 #endif
35 #define PAGE_SIZE	(_AC(1,UL) << PAGE_SHIFT)
36 #define PAGE_MASK	(~((1 << PAGE_SHIFT) - 1))
37 
38 /*
39  * This is used for calculating the real page sizes
40  * for FTLB or VTLB + FTLB configurations.
41  */
42 static inline unsigned int page_size_ftlb(unsigned int mmuextdef)
43 {
44 	switch (mmuextdef) {
45 	case MIPS_CONF4_MMUEXTDEF_FTLBSIZEEXT:
46 		if (PAGE_SIZE == (1 << 30))
47 			return 5;
48 		if (PAGE_SIZE == (1llu << 32))
49 			return 6;
50 		if (PAGE_SIZE > (256 << 10))
51 			return 7; /* reserved */
52 			/* fall through */
53 	case MIPS_CONF4_MMUEXTDEF_VTLBSIZEEXT:
54 		return (PAGE_SHIFT - 10) / 2;
55 	default:
56 		panic("Invalid FTLB configuration with Conf4_mmuextdef=%d value\n",
57 		      mmuextdef >> 14);
58 	}
59 }
60 
61 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
62 #define HPAGE_SHIFT	(PAGE_SHIFT + PAGE_SHIFT - 3)
63 #define HPAGE_SIZE	(_AC(1,UL) << HPAGE_SHIFT)
64 #define HPAGE_MASK	(~(HPAGE_SIZE - 1))
65 #define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
66 #else /* !CONFIG_MIPS_HUGE_TLB_SUPPORT */
67 #define HPAGE_SHIFT	({BUILD_BUG(); 0; })
68 #define HPAGE_SIZE	({BUILD_BUG(); 0; })
69 #define HPAGE_MASK	({BUILD_BUG(); 0; })
70 #define HUGETLB_PAGE_ORDER	({BUILD_BUG(); 0; })
71 #endif /* CONFIG_MIPS_HUGE_TLB_SUPPORT */
72 
73 #include <linux/pfn.h>
74 
75 extern void build_clear_page(void);
76 extern void build_copy_page(void);
77 
78 /*
79  * It's normally defined only for FLATMEM config but it's
80  * used in our early mem init code for all memory models.
81  * So always define it.
82  */
83 #define ARCH_PFN_OFFSET		PFN_UP(PHYS_OFFSET)
84 
85 extern void clear_page(void * page);
86 extern void copy_page(void * to, void * from);
87 
88 extern unsigned long shm_align_mask;
89 
90 static inline unsigned long pages_do_alias(unsigned long addr1,
91 	unsigned long addr2)
92 {
93 	return (addr1 ^ addr2) & shm_align_mask;
94 }
95 
96 struct page;
97 
98 static inline void clear_user_page(void *addr, unsigned long vaddr,
99 	struct page *page)
100 {
101 	extern void (*flush_data_cache_page)(unsigned long addr);
102 
103 	clear_page(addr);
104 	if (pages_do_alias((unsigned long) addr, vaddr & PAGE_MASK))
105 		flush_data_cache_page((unsigned long)addr);
106 }
107 
108 struct vm_area_struct;
109 extern void copy_user_highpage(struct page *to, struct page *from,
110 	unsigned long vaddr, struct vm_area_struct *vma);
111 
112 #define __HAVE_ARCH_COPY_USER_HIGHPAGE
113 
114 /*
115  * These are used to make use of C type-checking..
116  */
117 #ifdef CONFIG_PHYS_ADDR_T_64BIT
118   #ifdef CONFIG_CPU_MIPS32
119     typedef struct { unsigned long pte_low, pte_high; } pte_t;
120     #define pte_val(x)	  ((x).pte_low | ((unsigned long long)(x).pte_high << 32))
121     #define __pte(x)	  ({ pte_t __pte = {(x), ((unsigned long long)(x)) >> 32}; __pte; })
122   #else
123      typedef struct { unsigned long long pte; } pte_t;
124      #define pte_val(x) ((x).pte)
125      #define __pte(x)	((pte_t) { (x) } )
126   #endif
127 #else
128 typedef struct { unsigned long pte; } pte_t;
129 #define pte_val(x)	((x).pte)
130 #define __pte(x)	((pte_t) { (x) } )
131 #endif
132 typedef struct page *pgtable_t;
133 
134 /*
135  * Right now we don't support 4-level pagetables, so all pud-related
136  * definitions come from <asm-generic/pgtable-nopud.h>.
137  */
138 
139 /*
140  * Finall the top of the hierarchy, the pgd
141  */
142 typedef struct { unsigned long pgd; } pgd_t;
143 #define pgd_val(x)	((x).pgd)
144 #define __pgd(x)	((pgd_t) { (x) } )
145 
146 /*
147  * Manipulate page protection bits
148  */
149 typedef struct { unsigned long pgprot; } pgprot_t;
150 #define pgprot_val(x)	((x).pgprot)
151 #define __pgprot(x)	((pgprot_t) { (x) } )
152 
153 /*
154  * On R4000-style MMUs where a TLB entry is mapping a adjacent even / odd
155  * pair of pages we only have a single global bit per pair of pages.  When
156  * writing to the TLB make sure we always have the bit set for both pages
157  * or none.  This macro is used to access the `buddy' of the pte we're just
158  * working on.
159  */
160 #define ptep_buddy(x)	((pte_t *)((unsigned long)(x) ^ sizeof(pte_t)))
161 
162 /*
163  * __pa()/__va() should be used only during mem init.
164  */
165 static inline unsigned long ___pa(unsigned long x)
166 {
167 	if (config_enabled(CONFIG_64BIT)) {
168 		/*
169 		 * For MIPS64 the virtual address may either be in one of
170 		 * the compatibility segements ckseg0 or ckseg1, or it may
171 		 * be in xkphys.
172 		 */
173 		return x < CKSEG0 ? XPHYSADDR(x) : CPHYSADDR(x);
174 	}
175 
176 	if (!config_enabled(CONFIG_EVA)) {
177 		/*
178 		 * We're using the standard MIPS32 legacy memory map, ie.
179 		 * the address x is going to be in kseg0 or kseg1. We can
180 		 * handle either case by masking out the desired bits using
181 		 * CPHYSADDR.
182 		 */
183 		return CPHYSADDR(x);
184 	}
185 
186 	/*
187 	 * EVA is in use so the memory map could be anything, making it not
188 	 * safe to just mask out bits.
189 	 */
190 	return x - PAGE_OFFSET + PHYS_OFFSET;
191 }
192 #define __pa(x)		___pa((unsigned long)(x))
193 #define __va(x)		((void *)((unsigned long)(x) + PAGE_OFFSET - PHYS_OFFSET))
194 #include <asm/io.h>
195 
196 /*
197  * RELOC_HIDE was originally added by 6007b903dfe5f1d13e0c711ac2894bdd4a61b1ad
198  * (lmo) rsp. 8431fd094d625b94d364fe393076ccef88e6ce18 (kernel.org).  The
199  * discussion can be found in lkml posting
200  * <a2ebde260608230500o3407b108hc03debb9da6e62c@mail.gmail.com> which is
201  * archived at http://lists.linuxcoding.com/kernel/2006-q3/msg17360.html
202  *
203  * It is unclear if the misscompilations mentioned in
204  * http://lkml.org/lkml/2010/8/8/138 also affect MIPS so we keep this one
205  * until GCC 3.x has been retired before we can apply
206  * https://patchwork.linux-mips.org/patch/1541/
207  */
208 
209 #ifndef __pa_symbol
210 #define __pa_symbol(x)	__pa(RELOC_HIDE((unsigned long)(x), 0))
211 #endif
212 
213 #define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
214 
215 #ifdef CONFIG_FLATMEM
216 
217 static inline int pfn_valid(unsigned long pfn)
218 {
219 	/* avoid <linux/mm.h> include hell */
220 	extern unsigned long max_mapnr;
221 	unsigned long pfn_offset = ARCH_PFN_OFFSET;
222 
223 	return pfn >= pfn_offset && pfn < max_mapnr;
224 }
225 
226 #elif defined(CONFIG_SPARSEMEM)
227 
228 /* pfn_valid is defined in linux/mmzone.h */
229 
230 #elif defined(CONFIG_NEED_MULTIPLE_NODES)
231 
232 #define pfn_valid(pfn)							\
233 ({									\
234 	unsigned long __pfn = (pfn);					\
235 	int __n = pfn_to_nid(__pfn);					\
236 	((__n >= 0) ? (__pfn < NODE_DATA(__n)->node_start_pfn +		\
237 			       NODE_DATA(__n)->node_spanned_pages)	\
238 		    : 0);						\
239 })
240 
241 #endif
242 
243 #define virt_to_page(kaddr)	pfn_to_page(PFN_DOWN(virt_to_phys((void *)     \
244 								  (kaddr))))
245 
246 extern int __virt_addr_valid(const volatile void *kaddr);
247 #define virt_addr_valid(kaddr)						\
248 	__virt_addr_valid((const volatile void *) (kaddr))
249 
250 #define VM_DATA_DEFAULT_FLAGS \
251 	(VM_READ | VM_WRITE | \
252 	 ((current->personality & READ_IMPLIES_EXEC) ? VM_EXEC : 0) | \
253 	 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
254 
255 #define UNCAC_ADDR(addr)	((addr) - PAGE_OFFSET + UNCAC_BASE)
256 #define CAC_ADDR(addr)		((addr) - UNCAC_BASE + PAGE_OFFSET)
257 
258 #include <asm-generic/memory_model.h>
259 #include <asm-generic/getorder.h>
260 
261 #endif /* _ASM_PAGE_H */
262