xref: /openbmc/linux/arch/mips/include/asm/pgtable-64.h (revision 9b93eb47)
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, 95, 96, 97, 98, 99, 2000, 2003 Ralf Baechle
7  * Copyright (C) 1999, 2000, 2001 Silicon Graphics, Inc.
8  */
9 #ifndef _ASM_PGTABLE_64_H
10 #define _ASM_PGTABLE_64_H
11 
12 #include <linux/compiler.h>
13 #include <linux/linkage.h>
14 
15 #include <asm/addrspace.h>
16 #include <asm/page.h>
17 #include <asm/cachectl.h>
18 #include <asm/fixmap.h>
19 
20 #define __ARCH_USE_5LEVEL_HACK
21 #if defined(CONFIG_PAGE_SIZE_64KB) && !defined(CONFIG_MIPS_VA_BITS_48)
22 #include <asm-generic/pgtable-nopmd.h>
23 #elif !(defined(CONFIG_PAGE_SIZE_4KB) && defined(CONFIG_MIPS_VA_BITS_48))
24 #include <asm-generic/pgtable-nopud.h>
25 #endif
26 
27 /*
28  * Each address space has 2 4K pages as its page directory, giving 1024
29  * (== PTRS_PER_PGD) 8 byte pointers to pmd tables. Each pmd table is a
30  * single 4K page, giving 512 (== PTRS_PER_PMD) 8 byte pointers to page
31  * tables. Each page table is also a single 4K page, giving 512 (==
32  * PTRS_PER_PTE) 8 byte ptes. Each pud entry is initialized to point to
33  * invalid_pmd_table, each pmd entry is initialized to point to
34  * invalid_pte_table, each pte is initialized to 0.
35  *
36  * Kernel mappings: kernel mappings are held in the swapper_pg_table.
37  * The layout is identical to userspace except it's indexed with the
38  * fault address - VMALLOC_START.
39  */
40 
41 
42 /* PGDIR_SHIFT determines what a third-level page table entry can map */
43 #ifdef __PAGETABLE_PMD_FOLDED
44 #define PGDIR_SHIFT	(PAGE_SHIFT + PAGE_SHIFT + PTE_ORDER - 3)
45 #else
46 
47 /* PMD_SHIFT determines the size of the area a second-level page table can map */
48 #define PMD_SHIFT	(PAGE_SHIFT + (PAGE_SHIFT + PTE_ORDER - 3))
49 #define PMD_SIZE	(1UL << PMD_SHIFT)
50 #define PMD_MASK	(~(PMD_SIZE-1))
51 
52 # ifdef __PAGETABLE_PUD_FOLDED
53 # define PGDIR_SHIFT	(PMD_SHIFT + (PAGE_SHIFT + PMD_ORDER - 3))
54 # endif
55 #endif
56 
57 #ifndef __PAGETABLE_PUD_FOLDED
58 #define PUD_SHIFT	(PMD_SHIFT + (PAGE_SHIFT + PMD_ORDER - 3))
59 #define PUD_SIZE	(1UL << PUD_SHIFT)
60 #define PUD_MASK	(~(PUD_SIZE-1))
61 #define PGDIR_SHIFT	(PUD_SHIFT + (PAGE_SHIFT + PUD_ORDER - 3))
62 #endif
63 
64 #define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
65 #define PGDIR_MASK	(~(PGDIR_SIZE-1))
66 
67 /*
68  * For 4kB page size we use a 3 level page tree and an 8kB pud, which
69  * permits us mapping 40 bits of virtual address space.
70  *
71  * We used to implement 41 bits by having an order 1 pmd level but that seemed
72  * rather pointless.
73  *
74  * For 8kB page size we use a 3 level page tree which permits a total of
75  * 8TB of address space.  Alternatively a 33-bit / 8GB organization using
76  * two levels would be easy to implement.
77  *
78  * For 16kB page size we use a 2 level page tree which permits a total of
79  * 36 bits of virtual address space.  We could add a third level but it seems
80  * like at the moment there's no need for this.
81  *
82  * For 64kB page size we use a 2 level page table tree for a total of 42 bits
83  * of virtual address space.
84  */
85 #ifdef CONFIG_PAGE_SIZE_4KB
86 # ifdef CONFIG_MIPS_VA_BITS_48
87 #  define PGD_ORDER		0
88 #  define PUD_ORDER		0
89 # else
90 #  define PGD_ORDER		1
91 #  define PUD_ORDER		aieeee_attempt_to_allocate_pud
92 # endif
93 #define PMD_ORDER		0
94 #define PTE_ORDER		0
95 #endif
96 #ifdef CONFIG_PAGE_SIZE_8KB
97 #define PGD_ORDER		0
98 #define PUD_ORDER		aieeee_attempt_to_allocate_pud
99 #define PMD_ORDER		0
100 #define PTE_ORDER		0
101 #endif
102 #ifdef CONFIG_PAGE_SIZE_16KB
103 #ifdef CONFIG_MIPS_VA_BITS_48
104 #define PGD_ORDER               1
105 #else
106 #define PGD_ORDER               0
107 #endif
108 #define PUD_ORDER		aieeee_attempt_to_allocate_pud
109 #define PMD_ORDER		0
110 #define PTE_ORDER		0
111 #endif
112 #ifdef CONFIG_PAGE_SIZE_32KB
113 #define PGD_ORDER		0
114 #define PUD_ORDER		aieeee_attempt_to_allocate_pud
115 #define PMD_ORDER		0
116 #define PTE_ORDER		0
117 #endif
118 #ifdef CONFIG_PAGE_SIZE_64KB
119 #define PGD_ORDER		0
120 #define PUD_ORDER		aieeee_attempt_to_allocate_pud
121 #ifdef CONFIG_MIPS_VA_BITS_48
122 #define PMD_ORDER		0
123 #else
124 #define PMD_ORDER		aieeee_attempt_to_allocate_pmd
125 #endif
126 #define PTE_ORDER		0
127 #endif
128 
129 #define PTRS_PER_PGD	((PAGE_SIZE << PGD_ORDER) / sizeof(pgd_t))
130 #ifndef __PAGETABLE_PUD_FOLDED
131 #define PTRS_PER_PUD	((PAGE_SIZE << PUD_ORDER) / sizeof(pud_t))
132 #endif
133 #ifndef __PAGETABLE_PMD_FOLDED
134 #define PTRS_PER_PMD	((PAGE_SIZE << PMD_ORDER) / sizeof(pmd_t))
135 #endif
136 #define PTRS_PER_PTE	((PAGE_SIZE << PTE_ORDER) / sizeof(pte_t))
137 
138 #define USER_PTRS_PER_PGD       ((TASK_SIZE64 / PGDIR_SIZE)?(TASK_SIZE64 / PGDIR_SIZE):1)
139 #define FIRST_USER_ADDRESS	0UL
140 
141 /*
142  * TLB refill handlers also map the vmalloc area into xuseg.  Avoid
143  * the first couple of pages so NULL pointer dereferences will still
144  * reliably trap.
145  */
146 #define VMALLOC_START		(MAP_BASE + (2 * PAGE_SIZE))
147 #define VMALLOC_END	\
148 	(MAP_BASE + \
149 	 min(PTRS_PER_PGD * PTRS_PER_PUD * PTRS_PER_PMD * PTRS_PER_PTE * PAGE_SIZE, \
150 	     (1UL << cpu_vmbits)) - (1UL << 32))
151 
152 #if defined(CONFIG_MODULES) && defined(KBUILD_64BIT_SYM32) && \
153 	VMALLOC_START != CKSSEG
154 /* Load modules into 32bit-compatible segment. */
155 #define MODULE_START	CKSSEG
156 #define MODULE_END	(FIXADDR_START-2*PAGE_SIZE)
157 #endif
158 
159 #define pte_ERROR(e) \
160 	printk("%s:%d: bad pte %016lx.\n", __FILE__, __LINE__, pte_val(e))
161 #ifndef __PAGETABLE_PMD_FOLDED
162 #define pmd_ERROR(e) \
163 	printk("%s:%d: bad pmd %016lx.\n", __FILE__, __LINE__, pmd_val(e))
164 #endif
165 #ifndef __PAGETABLE_PUD_FOLDED
166 #define pud_ERROR(e) \
167 	printk("%s:%d: bad pud %016lx.\n", __FILE__, __LINE__, pud_val(e))
168 #endif
169 #define pgd_ERROR(e) \
170 	printk("%s:%d: bad pgd %016lx.\n", __FILE__, __LINE__, pgd_val(e))
171 
172 extern pte_t invalid_pte_table[PTRS_PER_PTE];
173 
174 #ifndef __PAGETABLE_PUD_FOLDED
175 /*
176  * For 4-level pagetables we defines these ourselves, for 3-level the
177  * definitions are below, for 2-level the
178  * definitions are supplied by <asm-generic/pgtable-nopmd.h>.
179  */
180 typedef struct { unsigned long pud; } pud_t;
181 #define pud_val(x)	((x).pud)
182 #define __pud(x)	((pud_t) { (x) })
183 
184 extern pud_t invalid_pud_table[PTRS_PER_PUD];
185 
186 /*
187  * Empty pgd entries point to the invalid_pud_table.
188  */
189 static inline int pgd_none(pgd_t pgd)
190 {
191 	return pgd_val(pgd) == (unsigned long)invalid_pud_table;
192 }
193 
194 static inline int pgd_bad(pgd_t pgd)
195 {
196 	if (unlikely(pgd_val(pgd) & ~PAGE_MASK))
197 		return 1;
198 
199 	return 0;
200 }
201 
202 static inline int pgd_present(pgd_t pgd)
203 {
204 	return pgd_val(pgd) != (unsigned long)invalid_pud_table;
205 }
206 
207 static inline void pgd_clear(pgd_t *pgdp)
208 {
209 	pgd_val(*pgdp) = (unsigned long)invalid_pud_table;
210 }
211 
212 #define pud_index(address)	(((address) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))
213 
214 static inline unsigned long pgd_page_vaddr(pgd_t pgd)
215 {
216 	return pgd_val(pgd);
217 }
218 
219 static inline pud_t *pud_offset(pgd_t *pgd, unsigned long address)
220 {
221 	return (pud_t *)pgd_page_vaddr(*pgd) + pud_index(address);
222 }
223 
224 static inline void set_pgd(pgd_t *pgd, pgd_t pgdval)
225 {
226 	*pgd = pgdval;
227 }
228 
229 #endif
230 
231 #ifndef __PAGETABLE_PMD_FOLDED
232 /*
233  * For 3-level pagetables we defines these ourselves, for 2-level the
234  * definitions are supplied by <asm-generic/pgtable-nopmd.h>.
235  */
236 typedef struct { unsigned long pmd; } pmd_t;
237 #define pmd_val(x)	((x).pmd)
238 #define __pmd(x)	((pmd_t) { (x) } )
239 
240 
241 extern pmd_t invalid_pmd_table[PTRS_PER_PMD];
242 #endif
243 
244 /*
245  * Empty pgd/pmd entries point to the invalid_pte_table.
246  */
247 static inline int pmd_none(pmd_t pmd)
248 {
249 	return pmd_val(pmd) == (unsigned long) invalid_pte_table;
250 }
251 
252 static inline int pmd_bad(pmd_t pmd)
253 {
254 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
255 	/* pmd_huge(pmd) but inline */
256 	if (unlikely(pmd_val(pmd) & _PAGE_HUGE))
257 		return 0;
258 #endif
259 
260 	if (unlikely(pmd_val(pmd) & ~PAGE_MASK))
261 		return 1;
262 
263 	return 0;
264 }
265 
266 static inline int pmd_present(pmd_t pmd)
267 {
268 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
269 	if (unlikely(pmd_val(pmd) & _PAGE_HUGE))
270 		return pmd_val(pmd) & _PAGE_PRESENT;
271 #endif
272 
273 	return pmd_val(pmd) != (unsigned long) invalid_pte_table;
274 }
275 
276 static inline void pmd_clear(pmd_t *pmdp)
277 {
278 	pmd_val(*pmdp) = ((unsigned long) invalid_pte_table);
279 }
280 #ifndef __PAGETABLE_PMD_FOLDED
281 
282 /*
283  * Empty pud entries point to the invalid_pmd_table.
284  */
285 static inline int pud_none(pud_t pud)
286 {
287 	return pud_val(pud) == (unsigned long) invalid_pmd_table;
288 }
289 
290 static inline int pud_bad(pud_t pud)
291 {
292 	return pud_val(pud) & ~PAGE_MASK;
293 }
294 
295 static inline int pud_present(pud_t pud)
296 {
297 	return pud_val(pud) != (unsigned long) invalid_pmd_table;
298 }
299 
300 static inline void pud_clear(pud_t *pudp)
301 {
302 	pud_val(*pudp) = ((unsigned long) invalid_pmd_table);
303 }
304 #endif
305 
306 #define pte_page(x)		pfn_to_page(pte_pfn(x))
307 
308 #ifdef CONFIG_CPU_VR41XX
309 #define pte_pfn(x)		((unsigned long)((x).pte >> (PAGE_SHIFT + 2)))
310 #define pfn_pte(pfn, prot)	__pte(((pfn) << (PAGE_SHIFT + 2)) | pgprot_val(prot))
311 #else
312 #define pte_pfn(x)		((unsigned long)((x).pte >> _PFN_SHIFT))
313 #define pfn_pte(pfn, prot)	__pte(((pfn) << _PFN_SHIFT) | pgprot_val(prot))
314 #define pfn_pmd(pfn, prot)	__pmd(((pfn) << _PFN_SHIFT) | pgprot_val(prot))
315 #endif
316 
317 #define __pgd_offset(address)	pgd_index(address)
318 #define __pud_offset(address)	(((address) >> PUD_SHIFT) & (PTRS_PER_PUD-1))
319 #define __pmd_offset(address)	pmd_index(address)
320 
321 /* to find an entry in a kernel page-table-directory */
322 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
323 
324 #define pgd_index(address)	(((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
325 #define pmd_index(address)	(((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
326 
327 /* to find an entry in a page-table-directory */
328 #define pgd_offset(mm, addr)	((mm)->pgd + pgd_index(addr))
329 
330 #ifndef __PAGETABLE_PMD_FOLDED
331 static inline unsigned long pud_page_vaddr(pud_t pud)
332 {
333 	return pud_val(pud);
334 }
335 #define pud_phys(pud)		virt_to_phys((void *)pud_val(pud))
336 #define pud_page(pud)		(pfn_to_page(pud_phys(pud) >> PAGE_SHIFT))
337 
338 /* Find an entry in the second-level page table.. */
339 static inline pmd_t *pmd_offset(pud_t * pud, unsigned long address)
340 {
341 	return (pmd_t *) pud_page_vaddr(*pud) + pmd_index(address);
342 }
343 #endif
344 
345 /* Find an entry in the third-level page table.. */
346 #define __pte_offset(address)						\
347 	(((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
348 #define pte_offset(dir, address)					\
349 	((pte_t *) pmd_page_vaddr(*(dir)) + __pte_offset(address))
350 #define pte_offset_kernel(dir, address)					\
351 	((pte_t *) pmd_page_vaddr(*(dir)) + __pte_offset(address))
352 #define pte_offset_map(dir, address)					\
353 	((pte_t *)page_address(pmd_page(*(dir))) + __pte_offset(address))
354 #define pte_unmap(pte) ((void)(pte))
355 
356 /*
357  * Initialize a new pgd / pmd table with invalid pointers.
358  */
359 extern void pgd_init(unsigned long page);
360 extern void pud_init(unsigned long page, unsigned long pagetable);
361 extern void pmd_init(unsigned long page, unsigned long pagetable);
362 
363 /*
364  * Non-present pages:  high 40 bits are offset, next 8 bits type,
365  * low 16 bits zero.
366  */
367 static inline pte_t mk_swap_pte(unsigned long type, unsigned long offset)
368 { pte_t pte; pte_val(pte) = (type << 16) | (offset << 24); return pte; }
369 
370 #define __swp_type(x)		(((x).val >> 16) & 0xff)
371 #define __swp_offset(x)		((x).val >> 24)
372 #define __swp_entry(type, offset) ((swp_entry_t) { pte_val(mk_swap_pte((type), (offset))) })
373 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
374 #define __swp_entry_to_pte(x)	((pte_t) { (x).val })
375 
376 #endif /* _ASM_PGTABLE_64_H */
377