xref: /openbmc/linux/arch/mips/include/asm/pgtable-64.h (revision e15a5365)
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 #if CONFIG_PGTABLE_LEVELS == 2
21 #include <asm-generic/pgtable-nopmd.h>
22 #elif CONFIG_PGTABLE_LEVELS == 3
23 #include <asm-generic/pgtable-nopud.h>
24 #else
25 #include <asm-generic/pgtable-nop4d.h>
26 #endif
27 
28 /*
29  * Each address space has 2 4K pages as its page directory, giving 1024
30  * (== PTRS_PER_PGD) 8 byte pointers to pmd tables. Each pmd table is a
31  * single 4K page, giving 512 (== PTRS_PER_PMD) 8 byte pointers to page
32  * tables. Each page table is also a single 4K page, giving 512 (==
33  * PTRS_PER_PTE) 8 byte ptes. Each pud entry is initialized to point to
34  * invalid_pmd_table, each pmd entry is initialized to point to
35  * invalid_pte_table, each pte is initialized to 0.
36  *
37  * Kernel mappings: kernel mappings are held in the swapper_pg_table.
38  * The layout is identical to userspace except it's indexed with the
39  * fault address - VMALLOC_START.
40  */
41 
42 
43 /* PGDIR_SHIFT determines what a third-level page table entry can map */
44 #ifdef __PAGETABLE_PMD_FOLDED
45 #define PGDIR_SHIFT	(PAGE_SHIFT + PAGE_SHIFT + PTE_ORDER - 3)
46 #else
47 
48 /* PMD_SHIFT determines the size of the area a second-level page table can map */
49 #define PMD_SHIFT	(PAGE_SHIFT + (PAGE_SHIFT + PTE_ORDER - 3))
50 #define PMD_SIZE	(1UL << PMD_SHIFT)
51 #define PMD_MASK	(~(PMD_SIZE-1))
52 
53 # ifdef __PAGETABLE_PUD_FOLDED
54 # define PGDIR_SHIFT	(PMD_SHIFT + (PAGE_SHIFT + PMD_ORDER - 3))
55 # endif
56 #endif
57 
58 #ifndef __PAGETABLE_PUD_FOLDED
59 #define PUD_SHIFT	(PMD_SHIFT + (PAGE_SHIFT + PMD_ORDER - 3))
60 #define PUD_SIZE	(1UL << PUD_SHIFT)
61 #define PUD_MASK	(~(PUD_SIZE-1))
62 #define PGDIR_SHIFT	(PUD_SHIFT + (PAGE_SHIFT + PUD_ORDER - 3))
63 #endif
64 
65 #define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
66 #define PGDIR_MASK	(~(PGDIR_SIZE-1))
67 
68 /*
69  * For 4kB page size we use a 3 level page tree and an 8kB pud, which
70  * permits us mapping 40 bits of virtual address space.
71  *
72  * We used to implement 41 bits by having an order 1 pmd level but that seemed
73  * rather pointless.
74  *
75  * For 8kB page size we use a 3 level page tree which permits a total of
76  * 8TB of address space.  Alternatively a 33-bit / 8GB organization using
77  * two levels would be easy to implement.
78  *
79  * For 16kB page size we use a 2 level page tree which permits a total of
80  * 36 bits of virtual address space.  We could add a third level but it seems
81  * like at the moment there's no need for this.
82  *
83  * For 64kB page size we use a 2 level page table tree for a total of 42 bits
84  * of virtual address space.
85  */
86 #ifdef CONFIG_PAGE_SIZE_4KB
87 # ifdef CONFIG_MIPS_VA_BITS_48
88 #  define PGD_ORDER		0
89 #  define PUD_ORDER		0
90 # else
91 #  define PGD_ORDER		1
92 #  define PUD_ORDER		aieeee_attempt_to_allocate_pud
93 # endif
94 #define PMD_ORDER		0
95 #define PTE_ORDER		0
96 #endif
97 #ifdef CONFIG_PAGE_SIZE_8KB
98 #define PGD_ORDER		0
99 #define PUD_ORDER		aieeee_attempt_to_allocate_pud
100 #define PMD_ORDER		0
101 #define PTE_ORDER		0
102 #endif
103 #ifdef CONFIG_PAGE_SIZE_16KB
104 #ifdef CONFIG_MIPS_VA_BITS_48
105 #define PGD_ORDER               1
106 #else
107 #define PGD_ORDER               0
108 #endif
109 #define PUD_ORDER		aieeee_attempt_to_allocate_pud
110 #define PMD_ORDER		0
111 #define PTE_ORDER		0
112 #endif
113 #ifdef CONFIG_PAGE_SIZE_32KB
114 #define PGD_ORDER		0
115 #define PUD_ORDER		aieeee_attempt_to_allocate_pud
116 #define PMD_ORDER		0
117 #define PTE_ORDER		0
118 #endif
119 #ifdef CONFIG_PAGE_SIZE_64KB
120 #define PGD_ORDER		0
121 #define PUD_ORDER		aieeee_attempt_to_allocate_pud
122 #ifdef CONFIG_MIPS_VA_BITS_48
123 #define PMD_ORDER		0
124 #else
125 #define PMD_ORDER		aieeee_attempt_to_allocate_pmd
126 #endif
127 #define PTE_ORDER		0
128 #endif
129 
130 #define PTRS_PER_PGD	((PAGE_SIZE << PGD_ORDER) / sizeof(pgd_t))
131 #ifndef __PAGETABLE_PUD_FOLDED
132 #define PTRS_PER_PUD	((PAGE_SIZE << PUD_ORDER) / sizeof(pud_t))
133 #endif
134 #ifndef __PAGETABLE_PMD_FOLDED
135 #define PTRS_PER_PMD	((PAGE_SIZE << PMD_ORDER) / sizeof(pmd_t))
136 #endif
137 #define PTRS_PER_PTE	((PAGE_SIZE << PTE_ORDER) / sizeof(pte_t))
138 
139 #define USER_PTRS_PER_PGD       ((TASK_SIZE64 / PGDIR_SIZE)?(TASK_SIZE64 / PGDIR_SIZE):1)
140 #define FIRST_USER_ADDRESS	0UL
141 
142 /*
143  * TLB refill handlers also map the vmalloc area into xuseg.  Avoid
144  * the first couple of pages so NULL pointer dereferences will still
145  * reliably trap.
146  */
147 #define VMALLOC_START		(MAP_BASE + (2 * PAGE_SIZE))
148 #define VMALLOC_END	\
149 	(MAP_BASE + \
150 	 min(PTRS_PER_PGD * PTRS_PER_PUD * PTRS_PER_PMD * PTRS_PER_PTE * PAGE_SIZE, \
151 	     (1UL << cpu_vmbits)) - (1UL << 32))
152 
153 #if defined(CONFIG_MODULES) && defined(KBUILD_64BIT_SYM32) && \
154 	VMALLOC_START != CKSSEG
155 /* Load modules into 32bit-compatible segment. */
156 #define MODULE_START	CKSSEG
157 #define MODULE_END	(FIXADDR_START-2*PAGE_SIZE)
158 #endif
159 
160 #define pte_ERROR(e) \
161 	printk("%s:%d: bad pte %016lx.\n", __FILE__, __LINE__, pte_val(e))
162 #ifndef __PAGETABLE_PMD_FOLDED
163 #define pmd_ERROR(e) \
164 	printk("%s:%d: bad pmd %016lx.\n", __FILE__, __LINE__, pmd_val(e))
165 #endif
166 #ifndef __PAGETABLE_PUD_FOLDED
167 #define pud_ERROR(e) \
168 	printk("%s:%d: bad pud %016lx.\n", __FILE__, __LINE__, pud_val(e))
169 #endif
170 #define pgd_ERROR(e) \
171 	printk("%s:%d: bad pgd %016lx.\n", __FILE__, __LINE__, pgd_val(e))
172 
173 extern pte_t invalid_pte_table[PTRS_PER_PTE];
174 
175 #ifndef __PAGETABLE_PUD_FOLDED
176 /*
177  * For 4-level pagetables we defines these ourselves, for 3-level the
178  * definitions are below, for 2-level the
179  * definitions are supplied by <asm-generic/pgtable-nopmd.h>.
180  */
181 typedef struct { unsigned long pud; } pud_t;
182 #define pud_val(x)	((x).pud)
183 #define __pud(x)	((pud_t) { (x) })
184 
185 extern pud_t invalid_pud_table[PTRS_PER_PUD];
186 
187 /*
188  * Empty pgd entries point to the invalid_pud_table.
189  */
190 static inline int p4d_none(p4d_t p4d)
191 {
192 	return p4d_val(p4d) == (unsigned long)invalid_pud_table;
193 }
194 
195 static inline int p4d_bad(p4d_t p4d)
196 {
197 	if (unlikely(p4d_val(p4d) & ~PAGE_MASK))
198 		return 1;
199 
200 	return 0;
201 }
202 
203 static inline int p4d_present(p4d_t p4d)
204 {
205 	return p4d_val(p4d) != (unsigned long)invalid_pud_table;
206 }
207 
208 static inline void p4d_clear(p4d_t *p4dp)
209 {
210 	p4d_val(*p4dp) = (unsigned long)invalid_pud_table;
211 }
212 
213 static inline unsigned long p4d_page_vaddr(p4d_t p4d)
214 {
215 	return p4d_val(p4d);
216 }
217 
218 #define p4d_phys(p4d)		virt_to_phys((void *)p4d_val(p4d))
219 #define p4d_page(p4d)		(pfn_to_page(p4d_phys(p4d) >> PAGE_SHIFT))
220 
221 #define p4d_index(address)	(((address) >> P4D_SHIFT) & (PTRS_PER_P4D - 1))
222 
223 static inline void set_p4d(p4d_t *p4d, p4d_t p4dval)
224 {
225 	*p4d = p4dval;
226 }
227 
228 #endif
229 
230 #ifndef __PAGETABLE_PMD_FOLDED
231 /*
232  * For 3-level pagetables we defines these ourselves, for 2-level the
233  * definitions are supplied by <asm-generic/pgtable-nopmd.h>.
234  */
235 typedef struct { unsigned long pmd; } pmd_t;
236 #define pmd_val(x)	((x).pmd)
237 #define __pmd(x)	((pmd_t) { (x) } )
238 
239 
240 extern pmd_t invalid_pmd_table[PTRS_PER_PMD];
241 #endif
242 
243 /*
244  * Empty pgd/pmd entries point to the invalid_pte_table.
245  */
246 static inline int pmd_none(pmd_t pmd)
247 {
248 	return pmd_val(pmd) == (unsigned long) invalid_pte_table;
249 }
250 
251 static inline int pmd_bad(pmd_t pmd)
252 {
253 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
254 	/* pmd_huge(pmd) but inline */
255 	if (unlikely(pmd_val(pmd) & _PAGE_HUGE))
256 		return 0;
257 #endif
258 
259 	if (unlikely(pmd_val(pmd) & ~PAGE_MASK))
260 		return 1;
261 
262 	return 0;
263 }
264 
265 static inline int pmd_present(pmd_t pmd)
266 {
267 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
268 	if (unlikely(pmd_val(pmd) & _PAGE_HUGE))
269 		return pmd_val(pmd) & _PAGE_PRESENT;
270 #endif
271 
272 	return pmd_val(pmd) != (unsigned long) invalid_pte_table;
273 }
274 
275 static inline void pmd_clear(pmd_t *pmdp)
276 {
277 	pmd_val(*pmdp) = ((unsigned long) invalid_pte_table);
278 }
279 #ifndef __PAGETABLE_PMD_FOLDED
280 
281 /*
282  * Empty pud entries point to the invalid_pmd_table.
283  */
284 static inline int pud_none(pud_t pud)
285 {
286 	return pud_val(pud) == (unsigned long) invalid_pmd_table;
287 }
288 
289 static inline int pud_bad(pud_t pud)
290 {
291 	return pud_val(pud) & ~PAGE_MASK;
292 }
293 
294 static inline int pud_present(pud_t pud)
295 {
296 	return pud_val(pud) != (unsigned long) invalid_pmd_table;
297 }
298 
299 static inline void pud_clear(pud_t *pudp)
300 {
301 	pud_val(*pudp) = ((unsigned long) invalid_pmd_table);
302 }
303 #endif
304 
305 #define pte_page(x)		pfn_to_page(pte_pfn(x))
306 
307 #ifdef CONFIG_CPU_VR41XX
308 #define pte_pfn(x)		((unsigned long)((x).pte >> (PAGE_SHIFT + 2)))
309 #define pfn_pte(pfn, prot)	__pte(((pfn) << (PAGE_SHIFT + 2)) | pgprot_val(prot))
310 #else
311 #define pte_pfn(x)		((unsigned long)((x).pte >> _PFN_SHIFT))
312 #define pfn_pte(pfn, prot)	__pte(((pfn) << _PFN_SHIFT) | pgprot_val(prot))
313 #define pfn_pmd(pfn, prot)	__pmd(((pfn) << _PFN_SHIFT) | pgprot_val(prot))
314 #endif
315 
316 #ifndef __PAGETABLE_PMD_FOLDED
317 static inline unsigned long pud_page_vaddr(pud_t pud)
318 {
319 	return pud_val(pud);
320 }
321 #define pud_phys(pud)		virt_to_phys((void *)pud_val(pud))
322 #define pud_page(pud)		(pfn_to_page(pud_phys(pud) >> PAGE_SHIFT))
323 
324 #endif
325 
326 /*
327  * Initialize a new pgd / pmd table with invalid pointers.
328  */
329 extern void pgd_init(unsigned long page);
330 extern void pud_init(unsigned long page, unsigned long pagetable);
331 extern void pmd_init(unsigned long page, unsigned long pagetable);
332 
333 /*
334  * Non-present pages:  high 40 bits are offset, next 8 bits type,
335  * low 16 bits zero.
336  */
337 static inline pte_t mk_swap_pte(unsigned long type, unsigned long offset)
338 { pte_t pte; pte_val(pte) = (type << 16) | (offset << 24); return pte; }
339 
340 #define __swp_type(x)		(((x).val >> 16) & 0xff)
341 #define __swp_offset(x)		((x).val >> 24)
342 #define __swp_entry(type, offset) ((swp_entry_t) { pte_val(mk_swap_pte((type), (offset))) })
343 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
344 #define __swp_entry_to_pte(x)	((pte_t) { (x).val })
345 
346 #endif /* _ASM_PGTABLE_64_H */
347