xref: /openbmc/linux/arch/csky/include/asm/pgtable.h (revision ccb01374)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
3 
4 #ifndef __ASM_CSKY_PGTABLE_H
5 #define __ASM_CSKY_PGTABLE_H
6 
7 #include <asm/fixmap.h>
8 #include <asm/addrspace.h>
9 #include <abi/pgtable-bits.h>
10 #include <asm-generic/pgtable-nopmd.h>
11 
12 #define PGDIR_SHIFT		22
13 #define PGDIR_SIZE		(1UL << PGDIR_SHIFT)
14 #define PGDIR_MASK		(~(PGDIR_SIZE-1))
15 
16 #define USER_PTRS_PER_PGD	(0x80000000UL/PGDIR_SIZE)
17 #define FIRST_USER_ADDRESS	0UL
18 
19 #define PKMAP_BASE		(0xff800000)
20 
21 #define VMALLOC_START		(0xc0008000)
22 #define VMALLOC_END		(PKMAP_BASE - 2*PAGE_SIZE)
23 
24 /*
25  * C-SKY is two-level paging structure:
26  */
27 #define PGD_ORDER	0
28 #define PTE_ORDER	0
29 
30 #define PTRS_PER_PGD	((PAGE_SIZE << PGD_ORDER) / sizeof(pgd_t))
31 #define PTRS_PER_PMD	1
32 #define PTRS_PER_PTE	((PAGE_SIZE << PTE_ORDER) / sizeof(pte_t))
33 
34 #define pte_ERROR(e) \
35 	pr_err("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, (e).pte_low)
36 #define pgd_ERROR(e) \
37 	pr_err("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
38 
39 /* Find an entry in the third-level page table.. */
40 #define __pte_offset_t(address) \
41 	(((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
42 #define pte_offset_kernel(dir, address) \
43 	(pmd_page_vaddr(*(dir)) + __pte_offset_t(address))
44 #define pte_offset_map(dir, address) \
45 	((pte_t *)page_address(pmd_page(*(dir))) + __pte_offset_t(address))
46 #define pmd_page(pmd)	(pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT))
47 #define pte_clear(mm, addr, ptep)	set_pte((ptep), \
48 			(((unsigned int)addr&0x80000000)?__pte(1):__pte(0)))
49 #define pte_none(pte)	(!(pte_val(pte)&0xfffffffe))
50 #define pte_present(pte)	(pte_val(pte) & _PAGE_PRESENT)
51 #define pte_pfn(x)	((unsigned long)((x).pte_low >> PAGE_SHIFT))
52 #define pfn_pte(pfn, prot) __pte(((unsigned long long)(pfn) << PAGE_SHIFT) \
53 				| pgprot_val(prot))
54 
55 #define __READABLE	(_PAGE_READ | _PAGE_VALID | _PAGE_ACCESSED)
56 #define __WRITEABLE	(_PAGE_WRITE | _PAGE_DIRTY | _PAGE_MODIFIED)
57 
58 #define _PAGE_CHG_MASK	(PAGE_MASK | _PAGE_ACCESSED | _PAGE_MODIFIED | \
59 			 _CACHE_MASK)
60 
61 #define pte_unmap(pte)	((void)(pte))
62 
63 #define __swp_type(x)			(((x).val >> 4) & 0xff)
64 #define __swp_offset(x)			((x).val >> 12)
65 #define __swp_entry(type, offset)	((swp_entry_t) {((type) << 4) | \
66 					((offset) << 12) })
67 #define __pte_to_swp_entry(pte)		((swp_entry_t) { pte_val(pte) })
68 #define __swp_entry_to_pte(x)		((pte_t) { (x).val })
69 
70 #define pte_page(x)			pfn_to_page(pte_pfn(x))
71 #define __mk_pte(page_nr, pgprot)	__pte(((page_nr) << PAGE_SHIFT) | \
72 					pgprot_val(pgprot))
73 
74 /*
75  * CSKY can't do page protection for execute, and considers that the same like
76  * read. Also, write permissions imply read permissions. This is the closest
77  * we can get by reasonable means..
78  */
79 #define PAGE_NONE	__pgprot(_PAGE_PRESENT | _CACHE_CACHED)
80 #define PAGE_SHARED	__pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | \
81 				_CACHE_CACHED)
82 #define PAGE_COPY	__pgprot(_PAGE_PRESENT | _PAGE_READ | _CACHE_CACHED)
83 #define PAGE_READONLY	__pgprot(_PAGE_PRESENT | _PAGE_READ | _CACHE_CACHED)
84 #define PAGE_KERNEL	__pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE | \
85 				_PAGE_GLOBAL | _CACHE_CACHED)
86 #define PAGE_USERIO	__pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | \
87 				_CACHE_CACHED)
88 
89 #define __P000	PAGE_NONE
90 #define __P001	PAGE_READONLY
91 #define __P010	PAGE_COPY
92 #define __P011	PAGE_COPY
93 #define __P100	PAGE_READONLY
94 #define __P101	PAGE_READONLY
95 #define __P110	PAGE_COPY
96 #define __P111	PAGE_COPY
97 
98 #define __S000	PAGE_NONE
99 #define __S001	PAGE_READONLY
100 #define __S010	PAGE_SHARED
101 #define __S011	PAGE_SHARED
102 #define __S100	PAGE_READONLY
103 #define __S101	PAGE_READONLY
104 #define __S110	PAGE_SHARED
105 #define __S111	PAGE_SHARED
106 
107 extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
108 #define ZERO_PAGE(vaddr)	(virt_to_page(empty_zero_page))
109 
110 extern void load_pgd(unsigned long pg_dir);
111 extern pte_t invalid_pte_table[PTRS_PER_PTE];
112 
113 static inline int pte_special(pte_t pte) { return 0; }
114 static inline pte_t pte_mkspecial(pte_t pte) { return pte; }
115 
116 static inline void set_pte(pte_t *p, pte_t pte)
117 {
118 	*p = pte;
119 #if defined(CONFIG_CPU_NEED_TLBSYNC)
120 	dcache_wb_line((u32)p);
121 #endif
122 	/* prevent out of order excution */
123 	smp_mb();
124 }
125 #define set_pte_at(mm, addr, ptep, pteval) set_pte(ptep, pteval)
126 
127 static inline pte_t *pmd_page_vaddr(pmd_t pmd)
128 {
129 	unsigned long ptr;
130 
131 	ptr = pmd_val(pmd);
132 
133 	return __va(ptr);
134 }
135 
136 #define pmd_phys(pmd) pmd_val(pmd)
137 
138 static inline void set_pmd(pmd_t *p, pmd_t pmd)
139 {
140 	*p = pmd;
141 #if defined(CONFIG_CPU_NEED_TLBSYNC)
142 	dcache_wb_line((u32)p);
143 #endif
144 	/* prevent specul excute */
145 	smp_mb();
146 }
147 
148 
149 static inline int pmd_none(pmd_t pmd)
150 {
151 	return pmd_val(pmd) == __pa(invalid_pte_table);
152 }
153 
154 #define pmd_bad(pmd)	(pmd_val(pmd) & ~PAGE_MASK)
155 
156 static inline int pmd_present(pmd_t pmd)
157 {
158 	return (pmd_val(pmd) != __pa(invalid_pte_table));
159 }
160 
161 static inline void pmd_clear(pmd_t *p)
162 {
163 	pmd_val(*p) = (__pa(invalid_pte_table));
164 #if defined(CONFIG_CPU_NEED_TLBSYNC)
165 	dcache_wb_line((u32)p);
166 #endif
167 }
168 
169 /*
170  * The following only work if pte_present() is true.
171  * Undefined behaviour if not..
172  */
173 static inline int pte_read(pte_t pte)
174 {
175 	return pte.pte_low & _PAGE_READ;
176 }
177 
178 static inline int pte_write(pte_t pte)
179 {
180 	return (pte).pte_low & _PAGE_WRITE;
181 }
182 
183 static inline int pte_dirty(pte_t pte)
184 {
185 	return (pte).pte_low & _PAGE_MODIFIED;
186 }
187 
188 static inline int pte_young(pte_t pte)
189 {
190 	return (pte).pte_low & _PAGE_ACCESSED;
191 }
192 
193 static inline pte_t pte_wrprotect(pte_t pte)
194 {
195 	pte_val(pte) &= ~(_PAGE_WRITE | _PAGE_DIRTY);
196 	return pte;
197 }
198 
199 static inline pte_t pte_mkclean(pte_t pte)
200 {
201 	pte_val(pte) &= ~(_PAGE_MODIFIED|_PAGE_DIRTY);
202 	return pte;
203 }
204 
205 static inline pte_t pte_mkold(pte_t pte)
206 {
207 	pte_val(pte) &= ~(_PAGE_ACCESSED|_PAGE_VALID);
208 	return pte;
209 }
210 
211 static inline pte_t pte_mkwrite(pte_t pte)
212 {
213 	pte_val(pte) |= _PAGE_WRITE;
214 	if (pte_val(pte) & _PAGE_MODIFIED)
215 		pte_val(pte) |= _PAGE_DIRTY;
216 	return pte;
217 }
218 
219 static inline pte_t pte_mkdirty(pte_t pte)
220 {
221 	pte_val(pte) |= _PAGE_MODIFIED;
222 	if (pte_val(pte) & _PAGE_WRITE)
223 		pte_val(pte) |= _PAGE_DIRTY;
224 	return pte;
225 }
226 
227 static inline pte_t pte_mkyoung(pte_t pte)
228 {
229 	pte_val(pte) |= _PAGE_ACCESSED;
230 	if (pte_val(pte) & _PAGE_READ)
231 		pte_val(pte) |= _PAGE_VALID;
232 	return pte;
233 }
234 
235 #define __pgd_offset(address)	pgd_index(address)
236 #define __pud_offset(address)	(((address) >> PUD_SHIFT) & (PTRS_PER_PUD-1))
237 #define __pmd_offset(address)	(((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
238 
239 /* to find an entry in a kernel page-table-directory */
240 #define pgd_offset_k(address)	pgd_offset(&init_mm, address)
241 
242 #define pgd_index(address)	((address) >> PGDIR_SHIFT)
243 
244 /*
245  * Macro to make mark a page protection value as "uncacheable".  Note
246  * that "protection" is really a misnomer here as the protection value
247  * contains the memory attribute bits, dirty bits, and various other
248  * bits as well.
249  */
250 #define pgprot_noncached pgprot_noncached
251 
252 static inline pgprot_t pgprot_noncached(pgprot_t _prot)
253 {
254 	unsigned long prot = pgprot_val(_prot);
255 
256 	prot = (prot & ~_CACHE_MASK) | _CACHE_UNCACHED;
257 
258 	return __pgprot(prot);
259 }
260 
261 /*
262  * Conversion functions: convert a page and protection to a page entry,
263  * and a page entry and page directory to the page they refer to.
264  */
265 #define mk_pte(page, pgprot)    pfn_pte(page_to_pfn(page), (pgprot))
266 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
267 {
268 	return __pte((pte_val(pte) & _PAGE_CHG_MASK) |
269 		     (pgprot_val(newprot)));
270 }
271 
272 /* to find an entry in a page-table-directory */
273 static inline pgd_t *pgd_offset(struct mm_struct *mm, unsigned long address)
274 {
275 	return mm->pgd + pgd_index(address);
276 }
277 
278 /* Find an entry in the third-level page table.. */
279 static inline pte_t *pte_offset(pmd_t *dir, unsigned long address)
280 {
281 	return (pte_t *) (pmd_page_vaddr(*dir)) +
282 		((address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));
283 }
284 
285 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
286 extern void paging_init(void);
287 
288 extern void show_jtlb_table(void);
289 
290 void update_mmu_cache(struct vm_area_struct *vma, unsigned long address,
291 		      pte_t *pte);
292 
293 /* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
294 #define kern_addr_valid(addr)	(1)
295 
296 /*
297  * No page table caches to initialise
298  */
299 #define pgtable_cache_init()	do {} while (0)
300 
301 #define io_remap_pfn_range(vma, vaddr, pfn, size, prot) \
302 	remap_pfn_range(vma, vaddr, pfn, size, prot)
303 
304 #include <asm-generic/pgtable.h>
305 
306 #endif /* __ASM_CSKY_PGTABLE_H */
307