1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * linux/arch/unicore32/include/asm/pgtable.h
4 *
5 * Code specific to PKUnity SoC and UniCore ISA
6 *
7 * Copyright (C) 2001-2010 GUAN Xue-tao
8 */
9 #ifndef __UNICORE_PGTABLE_H__
10 #define __UNICORE_PGTABLE_H__
11
12 #define __ARCH_USE_5LEVEL_HACK
13 #include <asm-generic/pgtable-nopmd.h>
14 #include <asm/cpu-single.h>
15
16 #include <asm/memory.h>
17 #include <asm/pgtable-hwdef.h>
18
19 /*
20 * Just any arbitrary offset to the start of the vmalloc VM area: the
21 * current 8MB value just means that there will be a 8MB "hole" after the
22 * physical memory until the kernel virtual memory starts. That means that
23 * any out-of-bounds memory accesses will hopefully be caught.
24 * The vmalloc() routines leaves a hole of 4kB between each vmalloced
25 * area for the same reason. ;)
26 *
27 * Note that platforms may override VMALLOC_START, but they must provide
28 * VMALLOC_END. VMALLOC_END defines the (exclusive) limit of this space,
29 * which may not overlap IO space.
30 */
31 #ifndef VMALLOC_START
32 #define VMALLOC_OFFSET SZ_8M
33 #define VMALLOC_START (((unsigned long)high_memory + VMALLOC_OFFSET) \
34 & ~(VMALLOC_OFFSET-1))
35 #define VMALLOC_END (0xff000000UL)
36 #endif
37
38 #define PTRS_PER_PTE 1024
39 #define PTRS_PER_PGD 1024
40
41 /*
42 * PGDIR_SHIFT determines what a third-level page table entry can map
43 */
44 #define PGDIR_SHIFT 22
45
46 #ifndef __ASSEMBLY__
47 extern void __pte_error(const char *file, int line, unsigned long val);
48 extern void __pgd_error(const char *file, int line, unsigned long val);
49
50 #define pte_ERROR(pte) __pte_error(__FILE__, __LINE__, pte_val(pte))
51 #define pgd_ERROR(pgd) __pgd_error(__FILE__, __LINE__, pgd_val(pgd))
52 #endif /* !__ASSEMBLY__ */
53
54 #define PGDIR_SIZE (1UL << PGDIR_SHIFT)
55 #define PGDIR_MASK (~(PGDIR_SIZE-1))
56
57 /*
58 * This is the lowest virtual address we can permit any user space
59 * mapping to be mapped at. This is particularly important for
60 * non-high vector CPUs.
61 */
62 #define FIRST_USER_ADDRESS PAGE_SIZE
63
64 #define FIRST_USER_PGD_NR 1
65 #define USER_PTRS_PER_PGD ((TASK_SIZE/PGDIR_SIZE) - FIRST_USER_PGD_NR)
66
67 /*
68 * section address mask and size definitions.
69 */
70 #define SECTION_SHIFT 22
71 #define SECTION_SIZE (1UL << SECTION_SHIFT)
72 #define SECTION_MASK (~(SECTION_SIZE-1))
73
74 #ifndef __ASSEMBLY__
75
76 /*
77 * The pgprot_* and protection_map entries will be fixed up in runtime
78 * to include the cachable bits based on memory policy, as well as any
79 * architecture dependent bits.
80 */
81 #define _PTE_DEFAULT (PTE_PRESENT | PTE_YOUNG | PTE_CACHEABLE)
82
83 extern pgprot_t pgprot_user;
84 extern pgprot_t pgprot_kernel;
85
86 #define PAGE_NONE pgprot_user
87 #define PAGE_SHARED __pgprot(pgprot_val(pgprot_user | PTE_READ \
88 | PTE_WRITE))
89 #define PAGE_SHARED_EXEC __pgprot(pgprot_val(pgprot_user | PTE_READ \
90 | PTE_WRITE \
91 | PTE_EXEC))
92 #define PAGE_COPY __pgprot(pgprot_val(pgprot_user | PTE_READ)
93 #define PAGE_COPY_EXEC __pgprot(pgprot_val(pgprot_user | PTE_READ \
94 | PTE_EXEC))
95 #define PAGE_READONLY __pgprot(pgprot_val(pgprot_user | PTE_READ))
96 #define PAGE_READONLY_EXEC __pgprot(pgprot_val(pgprot_user | PTE_READ \
97 | PTE_EXEC))
98 #define PAGE_KERNEL pgprot_kernel
99 #define PAGE_KERNEL_EXEC __pgprot(pgprot_val(pgprot_kernel | PTE_EXEC))
100
101 #define __PAGE_NONE __pgprot(_PTE_DEFAULT)
102 #define __PAGE_SHARED __pgprot(_PTE_DEFAULT | PTE_READ \
103 | PTE_WRITE)
104 #define __PAGE_SHARED_EXEC __pgprot(_PTE_DEFAULT | PTE_READ \
105 | PTE_WRITE \
106 | PTE_EXEC)
107 #define __PAGE_COPY __pgprot(_PTE_DEFAULT | PTE_READ)
108 #define __PAGE_COPY_EXEC __pgprot(_PTE_DEFAULT | PTE_READ \
109 | PTE_EXEC)
110 #define __PAGE_READONLY __pgprot(_PTE_DEFAULT | PTE_READ)
111 #define __PAGE_READONLY_EXEC __pgprot(_PTE_DEFAULT | PTE_READ \
112 | PTE_EXEC)
113
114 #endif /* __ASSEMBLY__ */
115
116 /*
117 * The table below defines the page protection levels that we insert into our
118 * Linux page table version. These get translated into the best that the
119 * architecture can perform. Note that on UniCore hardware:
120 * 1) We cannot do execute protection
121 * 2) If we could do execute protection, then read is implied
122 * 3) write implies read permissions
123 */
124 #define __P000 __PAGE_NONE
125 #define __P001 __PAGE_READONLY
126 #define __P010 __PAGE_COPY
127 #define __P011 __PAGE_COPY
128 #define __P100 __PAGE_READONLY_EXEC
129 #define __P101 __PAGE_READONLY_EXEC
130 #define __P110 __PAGE_COPY_EXEC
131 #define __P111 __PAGE_COPY_EXEC
132
133 #define __S000 __PAGE_NONE
134 #define __S001 __PAGE_READONLY
135 #define __S010 __PAGE_SHARED
136 #define __S011 __PAGE_SHARED
137 #define __S100 __PAGE_READONLY_EXEC
138 #define __S101 __PAGE_READONLY_EXEC
139 #define __S110 __PAGE_SHARED_EXEC
140 #define __S111 __PAGE_SHARED_EXEC
141
142 #ifndef __ASSEMBLY__
143 /*
144 * ZERO_PAGE is a global shared page that is always zero: used
145 * for zero-mapped memory areas etc..
146 */
147 extern struct page *empty_zero_page;
148 #define ZERO_PAGE(vaddr) (empty_zero_page)
149
150 #define pte_pfn(pte) (pte_val(pte) >> PAGE_SHIFT)
151 #define pfn_pte(pfn, prot) (__pte(((pfn) << PAGE_SHIFT) \
152 | pgprot_val(prot)))
153
154 #define pte_none(pte) (!pte_val(pte))
155 #define pte_clear(mm, addr, ptep) set_pte(ptep, __pte(0))
156 #define pte_page(pte) (pfn_to_page(pte_pfn(pte)))
157 #define pte_offset_kernel(dir, addr) (pmd_page_vaddr(*(dir)) \
158 + __pte_index(addr))
159
160 #define pte_offset_map(dir, addr) (pmd_page_vaddr(*(dir)) \
161 + __pte_index(addr))
162 #define pte_unmap(pte) do { } while (0)
163
164 #define set_pte(ptep, pte) cpu_set_pte(ptep, pte)
165
166 #define set_pte_at(mm, addr, ptep, pteval) \
167 do { \
168 set_pte(ptep, pteval); \
169 } while (0)
170
171 /*
172 * The following only work if pte_present() is true.
173 * Undefined behaviour if not..
174 */
175 #define pte_present(pte) (pte_val(pte) & PTE_PRESENT)
176 #define pte_write(pte) (pte_val(pte) & PTE_WRITE)
177 #define pte_dirty(pte) (pte_val(pte) & PTE_DIRTY)
178 #define pte_young(pte) (pte_val(pte) & PTE_YOUNG)
179 #define pte_exec(pte) (pte_val(pte) & PTE_EXEC)
180 #define pte_special(pte) (0)
181
182 #define PTE_BIT_FUNC(fn, op) \
183 static inline pte_t pte_##fn(pte_t pte) { pte_val(pte) op; return pte; }
184
185 PTE_BIT_FUNC(wrprotect, &= ~PTE_WRITE);
186 PTE_BIT_FUNC(mkwrite, |= PTE_WRITE);
187 PTE_BIT_FUNC(mkclean, &= ~PTE_DIRTY);
188 PTE_BIT_FUNC(mkdirty, |= PTE_DIRTY);
189 PTE_BIT_FUNC(mkold, &= ~PTE_YOUNG);
190 PTE_BIT_FUNC(mkyoung, |= PTE_YOUNG);
191
pte_mkspecial(pte_t pte)192 static inline pte_t pte_mkspecial(pte_t pte) { return pte; }
193
194 /*
195 * Mark the prot value as uncacheable.
196 */
197 #define pgprot_noncached(prot) \
198 __pgprot(pgprot_val(prot) & ~PTE_CACHEABLE)
199 #define pgprot_writecombine(prot) \
200 __pgprot(pgprot_val(prot) & ~PTE_CACHEABLE)
201
202 #define pmd_none(pmd) (!pmd_val(pmd))
203 #define pmd_present(pmd) (pmd_val(pmd) & PMD_PRESENT)
204 #define pmd_bad(pmd) (((pmd_val(pmd) & \
205 (PMD_PRESENT | PMD_TYPE_MASK)) \
206 != (PMD_PRESENT | PMD_TYPE_TABLE)))
207
208 #define set_pmd(pmdpd, pmdval) \
209 do { \
210 *(pmdpd) = pmdval; \
211 } while (0)
212
213 #define pmd_clear(pmdp) \
214 do { \
215 set_pmd(pmdp, __pmd(0));\
216 clean_pmd_entry(pmdp); \
217 } while (0)
218
219 #define pmd_page_vaddr(pmd) ((pte_t *)__va(pmd_val(pmd) & PAGE_MASK))
220 #define pmd_page(pmd) pfn_to_page(__phys_to_pfn(pmd_val(pmd)))
221
222 /*
223 * Conversion functions: convert a page and protection to a page entry,
224 * and a page entry and page directory to the page they refer to.
225 */
226 #define mk_pte(page, prot) pfn_pte(page_to_pfn(page), prot)
227
228 /* to find an entry in a page-table-directory */
229 #define pgd_index(addr) ((addr) >> PGDIR_SHIFT)
230
231 #define pgd_offset(mm, addr) ((mm)->pgd+pgd_index(addr))
232
233 /* to find an entry in a kernel page-table-directory */
234 #define pgd_offset_k(addr) pgd_offset(&init_mm, addr)
235
236 /* Find an entry in the third-level page table.. */
237 #define __pte_index(addr) (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
238
pte_modify(pte_t pte,pgprot_t newprot)239 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
240 {
241 const unsigned long mask = PTE_EXEC | PTE_WRITE | PTE_READ;
242 pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
243 return pte;
244 }
245
246 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
247
248 /*
249 * Encode and decode a swap entry. Swap entries are stored in the Linux
250 * page tables as follows:
251 *
252 * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
253 * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
254 * <--------------- offset --------------> <--- type --> 0 0 0 0 0
255 *
256 * This gives us up to 127 swap files and 32GB per swap file. Note that
257 * the offset field is always non-zero.
258 */
259 #define __SWP_TYPE_SHIFT 5
260 #define __SWP_TYPE_BITS 7
261 #define __SWP_TYPE_MASK ((1 << __SWP_TYPE_BITS) - 1)
262 #define __SWP_OFFSET_SHIFT (__SWP_TYPE_BITS + __SWP_TYPE_SHIFT)
263
264 #define __swp_type(x) (((x).val >> __SWP_TYPE_SHIFT) \
265 & __SWP_TYPE_MASK)
266 #define __swp_offset(x) ((x).val >> __SWP_OFFSET_SHIFT)
267 #define __swp_entry(type, offset) ((swp_entry_t) { \
268 ((type) << __SWP_TYPE_SHIFT) | \
269 ((offset) << __SWP_OFFSET_SHIFT) })
270
271 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
272 #define __swp_entry_to_pte(swp) ((pte_t) { (swp).val })
273
274 /*
275 * It is an error for the kernel to have more swap files than we can
276 * encode in the PTEs. This ensures that we know when MAX_SWAPFILES
277 * is increased beyond what we presently support.
278 */
279 #define MAX_SWAPFILES_CHECK() \
280 BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
281
282 /* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
283 /* FIXME: this is not correct */
284 #define kern_addr_valid(addr) (1)
285
286 #include <asm-generic/pgtable.h>
287
288 #endif /* !__ASSEMBLY__ */
289
290 #endif /* __UNICORE_PGTABLE_H__ */
291
