1 #ifndef __ASM_SH_PGTABLE_H
2 #define __ASM_SH_PGTABLE_H
3 
4 /* Copyright (C) 1999 Niibe Yutaka */
5 
6 #include <asm/pgtable-2level.h>
7 
8 /*
9  * This file contains the functions and defines necessary to modify and use
10  * the SuperH page table tree.
11  */
12 #ifndef __ASSEMBLY__
13 #include <asm/processor.h>
14 #include <asm/addrspace.h>
15 #include <linux/threads.h>
16 
17 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
18 extern void paging_init(void);
19 
20 #if defined(__sh3__)
21 /* Cache flushing:
22  *
23  *  - flush_cache_all() flushes entire cache
24  *  - flush_cache_mm(mm) flushes the specified mm context's cache lines
25  *  - flush_cache_page(mm, vmaddr) flushes a single page
26  *  - flush_cache_range(mm, start, end) flushes a range of pages
27  *
28  *  - flush_dcache_page(pg) flushes(wback&invalidates) a page for dcache
29  *  - flush_page_to_ram(page) write back kernel page to ram
30  *  - flush_icache_range(start, end) flushes(invalidates) a range for icache
31  *  - flush_icache_page(vma, pg) flushes(invalidates) a page for icache
32  *
33  *  Caches are indexed (effectively) by physical address on SH-3, so
34  *  we don't need them.
35  */
36 #define flush_cache_all()			do { } while (0)
37 #define flush_cache_mm(mm)			do { } while (0)
38 #define flush_cache_range(mm, start, end)	do { } while (0)
39 #define flush_cache_page(vma, vmaddr)		do { } while (0)
40 #define flush_page_to_ram(page)			do { } while (0)
41 #define flush_dcache_page(page)			do { } while (0)
42 #define flush_icache_range(start, end)		do { } while (0)
43 #define flush_icache_page(vma,pg)		do { } while (0)
44 #define flush_icache_user_range(vma,pg,adr,len)	do { } while (0)
45 #define flush_cache_sigtramp(vaddr)		do { } while (0)
46 #define __flush_icache_all()			do { } while (0)
47 
48 #define p3_cache_init()				do { } while (0)
49 
50 #elif defined(__SH4__)
51 /*
52  *  Caches are broken on SH-4, so we need them.
53  */
54 
55 /* Page is 4K, OC size is 16K, there are four lines. */
56 #define CACHE_ALIAS 0x00003000
57 
58 extern void flush_cache_all(void);
59 extern void flush_cache_mm(struct mm_struct *mm);
60 extern void flush_cache_range(struct mm_struct *mm, unsigned long start,
61 			      unsigned long end);
62 extern void flush_cache_page(struct vm_area_struct *vma, unsigned long addr);
63 extern void flush_dcache_page(struct page *pg);
64 extern void flush_icache_range(unsigned long start, unsigned long end);
65 extern void flush_cache_sigtramp(unsigned long addr);
66 
67 #define flush_page_to_ram(page)			do { } while (0)
68 #define flush_icache_page(vma,pg)		do { } while (0)
69 #define flush_icache_user_range(vma,pg,adr,len)	do { } while (0)
70 
71 /* Initialization of P3 area for copy_user_page */
72 extern void p3_cache_init(void);
73 
74 #define PG_mapped	PG_arch_1
75 
76 /* We provide our own get_unmapped_area to avoid cache alias issue */
77 #define HAVE_ARCH_UNMAPPED_AREA
78 #endif
79 
80 /* Flush (write-back only) a region (smaller than a page) */
81 extern void __flush_wback_region(void *start, int size);
82 /* Flush (write-back & invalidate) a region (smaller than a page) */
83 extern void __flush_purge_region(void *start, int size);
84 /* Flush (invalidate only) a region (smaller than a page) */
85 extern void __flush_invalidate_region(void *start, int size);
86 
87 
88 /*
89  * Basically we have the same two-level (which is the logical three level
90  * Linux page table layout folded) page tables as the i386.
91  */
92 
93 /*
94  * ZERO_PAGE is a global shared page that is always zero: used
95  * for zero-mapped memory areas etc..
96  */
97 extern unsigned long empty_zero_page[1024];
98 #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
99 
100 #endif /* !__ASSEMBLY__ */
101 
102 #define __beep() asm("")
103 
104 #define PMD_SIZE	(1UL << PMD_SHIFT)
105 #define PMD_MASK	(~(PMD_SIZE-1))
106 #define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
107 #define PGDIR_MASK	(~(PGDIR_SIZE-1))
108 
109 #define USER_PTRS_PER_PGD	(TASK_SIZE/PGDIR_SIZE)
110 #define FIRST_USER_PGD_NR	0
111 
112 #define PTE_PHYS_MASK	0x1ffff000
113 
114 #ifndef __ASSEMBLY__
115 /*
116  * First 1MB map is used by fixed purpose.
117  * Currently only 4-enty (16kB) is used (see arch/sh/mm/cache.c)
118  */
119 #define VMALLOC_START	(P3SEG+0x00100000)
120 #define VMALLOC_VMADDR(x) ((unsigned long)(x))
121 #define VMALLOC_END	P4SEG
122 
123 /*			0x001     WT-bit on SH-4, 0 on SH-3 */
124 #define _PAGE_HW_SHARED	0x002  /* SH-bit  : page is shared among processes */
125 #define _PAGE_DIRTY	0x004  /* D-bit   : page changed */
126 #define _PAGE_CACHABLE	0x008  /* C-bit   : cachable */
127 /*			0x010     SZ0-bit : Size of page */
128 #define _PAGE_RW	0x020  /* PR0-bit : write access allowed */
129 #define _PAGE_USER	0x040  /* PR1-bit : user space access allowed */
130 /*			0x080     SZ1-bit : Size of page (on SH-4) */
131 #define _PAGE_PRESENT	0x100  /* V-bit   : page is valid */
132 #define _PAGE_PROTNONE	0x200  /* software: if not present  */
133 #define _PAGE_ACCESSED 	0x400  /* software: page referenced */
134 #define _PAGE_U0_SHARED 0x800  /* software: page is shared in user space */
135 
136 
137 /* software: moves to PTEA.TC (Timing Control) */
138 #define _PAGE_PCC_AREA5	0x00000000	/* use BSC registers for area5 */
139 #define _PAGE_PCC_AREA6	0x80000000	/* use BSC registers for area6 */
140 
141 /* software: moves to PTEA.SA[2:0] (Space Attributes) */
142 #define _PAGE_PCC_IODYN 0x00000001	/* IO space, dynamically sized bus */
143 #define _PAGE_PCC_IO8	0x20000000	/* IO space, 8 bit bus */
144 #define _PAGE_PCC_IO16	0x20000001	/* IO space, 16 bit bus */
145 #define _PAGE_PCC_COM8	0x40000000	/* Common Memory space, 8 bit bus */
146 #define _PAGE_PCC_COM16	0x40000001	/* Common Memory space, 16 bit bus */
147 #define _PAGE_PCC_ATR8	0x60000000	/* Attribute Memory space, 8 bit bus */
148 #define _PAGE_PCC_ATR16	0x60000001	/* Attribute Memory space, 6 bit bus */
149 
150 
151 /* Mask which drop software flags */
152 #if defined(__sh3__)
153 /*
154  * MMU on SH-3 has bug on SH-bit: We can't use it if MMUCR.IX=1.
155  * Work around: Just drop SH-bit.
156  */
157 #define _PAGE_FLAGS_HARDWARE_MASK	0x1ffff1fc
158 #else
159 #define _PAGE_FLAGS_HARDWARE_MASK	0x1ffff1fe
160 #endif
161 /* Hardware flags: SZ=1 (4k-byte) */
162 #define _PAGE_FLAGS_HARD		0x00000010
163 
164 #define _PAGE_SHARED	_PAGE_U0_SHARED
165 
166 #define _PAGE_TABLE	(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED | _PAGE_DIRTY)
167 #define _KERNPG_TABLE	(_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY)
168 #define _PAGE_CHG_MASK	(PTE_MASK | _PAGE_ACCESSED | _PAGE_CACHABLE | _PAGE_DIRTY | _PAGE_SHARED)
169 
170 #define PAGE_NONE	__pgprot(_PAGE_PROTNONE | _PAGE_CACHABLE |_PAGE_ACCESSED | _PAGE_FLAGS_HARD)
171 #define PAGE_SHARED	__pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_CACHABLE |_PAGE_ACCESSED | _PAGE_SHARED | _PAGE_FLAGS_HARD)
172 #define PAGE_COPY	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_CACHABLE | _PAGE_ACCESSED | _PAGE_FLAGS_HARD)
173 #define PAGE_READONLY	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_CACHABLE | _PAGE_ACCESSED | _PAGE_FLAGS_HARD)
174 #define PAGE_KERNEL	__pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_CACHABLE | _PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_HW_SHARED | _PAGE_FLAGS_HARD)
175 #define PAGE_KERNEL_RO	__pgprot(_PAGE_PRESENT | _PAGE_CACHABLE | _PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_HW_SHARED | _PAGE_FLAGS_HARD)
176 #define PAGE_KERNEL_PCC(slot, type) \
177 			__pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_FLAGS_HARD | (slot ? _PAGE_PCC_AREA5 : _PAGE_PCC_AREA6) | (type))
178 
179 /*
180  * As i386 and MIPS, SuperH can't do page protection for execute, and
181  * considers that the same as a read.  Also, write permissions imply
182  * read permissions. This is the closest we can get..
183  */
184 
185 #define __P000	PAGE_NONE
186 #define __P001	PAGE_READONLY
187 #define __P010	PAGE_COPY
188 #define __P011	PAGE_COPY
189 #define __P100	PAGE_READONLY
190 #define __P101	PAGE_READONLY
191 #define __P110	PAGE_COPY
192 #define __P111	PAGE_COPY
193 
194 #define __S000	PAGE_NONE
195 #define __S001	PAGE_READONLY
196 #define __S010	PAGE_SHARED
197 #define __S011	PAGE_SHARED
198 #define __S100	PAGE_READONLY
199 #define __S101	PAGE_READONLY
200 #define __S110	PAGE_SHARED
201 #define __S111	PAGE_SHARED
202 
203 #define pte_none(x)	(!pte_val(x))
204 #define pte_present(x)	(pte_val(x) & (_PAGE_PRESENT | _PAGE_PROTNONE))
205 #define pte_clear(xp)	do { set_pte(xp, __pte(0)); } while (0)
206 
207 #define pmd_none(x)	(!pmd_val(x))
208 #define pmd_present(x)	(pmd_val(x) & _PAGE_PRESENT)
209 #define pmd_clear(xp)	do { set_pmd(xp, __pmd(0)); } while (0)
210 #define	pmd_bad(x)	((pmd_val(x) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE)
211 
212 #define pages_to_mb(x)	((x) >> (20-PAGE_SHIFT))
213 #define pte_page(x) 	phys_to_page(pte_val(x)&PTE_PHYS_MASK)
214 
215 /*
216  * The following only work if pte_present() is true.
217  * Undefined behaviour if not..
218  */
pte_read(pte_t pte)219 static inline int pte_read(pte_t pte) { return pte_val(pte) & _PAGE_USER; }
pte_exec(pte_t pte)220 static inline int pte_exec(pte_t pte) { return pte_val(pte) & _PAGE_USER; }
pte_dirty(pte_t pte)221 static inline int pte_dirty(pte_t pte){ return pte_val(pte) & _PAGE_DIRTY; }
pte_young(pte_t pte)222 static inline int pte_young(pte_t pte){ return pte_val(pte) & _PAGE_ACCESSED; }
pte_write(pte_t pte)223 static inline int pte_write(pte_t pte){ return pte_val(pte) & _PAGE_RW; }
pte_not_present(pte_t pte)224 static inline int pte_not_present(pte_t pte){ return !(pte_val(pte) & _PAGE_PRESENT); }
225 
pte_rdprotect(pte_t pte)226 static inline pte_t pte_rdprotect(pte_t pte)	{ set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_USER)); return pte; }
pte_exprotect(pte_t pte)227 static inline pte_t pte_exprotect(pte_t pte)	{ set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_USER)); return pte; }
pte_mkclean(pte_t pte)228 static inline pte_t pte_mkclean(pte_t pte)	{ set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_DIRTY)); return pte; }
pte_mkold(pte_t pte)229 static inline pte_t pte_mkold(pte_t pte)	{ set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_ACCESSED)); return pte; }
pte_wrprotect(pte_t pte)230 static inline pte_t pte_wrprotect(pte_t pte)	{ set_pte(&pte, __pte(pte_val(pte) & ~_PAGE_RW)); return pte; }
pte_mkread(pte_t pte)231 static inline pte_t pte_mkread(pte_t pte)	{ set_pte(&pte, __pte(pte_val(pte) | _PAGE_USER)); return pte; }
pte_mkexec(pte_t pte)232 static inline pte_t pte_mkexec(pte_t pte)	{ set_pte(&pte, __pte(pte_val(pte) | _PAGE_USER)); return pte; }
pte_mkdirty(pte_t pte)233 static inline pte_t pte_mkdirty(pte_t pte)	{ set_pte(&pte, __pte(pte_val(pte) | _PAGE_DIRTY)); return pte; }
pte_mkyoung(pte_t pte)234 static inline pte_t pte_mkyoung(pte_t pte)	{ set_pte(&pte, __pte(pte_val(pte) | _PAGE_ACCESSED)); return pte; }
pte_mkwrite(pte_t pte)235 static inline pte_t pte_mkwrite(pte_t pte)	{ set_pte(&pte, __pte(pte_val(pte) | _PAGE_RW)); return pte; }
236 
237 /*
238  * Conversion functions: convert a page and protection to a page entry,
239  * and a page entry and page directory to the page they refer to.
240  *
241  * extern pte_t mk_pte(struct page *page, pgprot_t pgprot)
242  */
243 #define mk_pte(page,pgprot)						\
244 ({	pte_t __pte;							\
245 									\
246 	set_pte(&__pte, __pte(PHYSADDR(page_address(page))		\
247 				+pgprot_val(pgprot)));			\
248 	__pte;								\
249 })
250 
251 /* This takes a physical page address that is used by the remapping functions */
252 #define mk_pte_phys(physpage, pgprot) \
253 ({ pte_t __pte; set_pte(&__pte, __pte(physpage + pgprot_val(pgprot))); __pte; })
254 
pte_modify(pte_t pte,pgprot_t newprot)255 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
256 { set_pte(&pte, __pte((pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot))); return pte; }
257 
258 #define page_pte(page) page_pte_prot(page, __pgprot(0))
259 
260 #define pmd_page(pmd) \
261 ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
262 
263 /* to find an entry in a page-table-directory. */
264 #define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
265 #define __pgd_offset(address) pgd_index(address)
266 #define pgd_offset(mm, address) ((mm)->pgd+pgd_index(address))
267 
268 /* to find an entry in a kernel page-table-directory */
269 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
270 
271 /* Find an entry in the third-level page table.. */
272 #define __pte_offset(address) \
273 		((address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
274 #define pte_offset(dir, address) ((pte_t *) pmd_page(*(dir)) + \
275 			__pte_offset(address))
276 
277 extern void update_mmu_cache(struct vm_area_struct * vma,
278 			     unsigned long address, pte_t pte);
279 
280 /* Encode and de-code a swap entry */
281 /*
282  * NOTE: We should set ZEROs at the position of _PAGE_PRESENT
283  *       and _PAGE_PROTONOE bits
284  */
285 #define SWP_TYPE(x)		((x).val & 0xff)
286 #define SWP_OFFSET(x)		((x).val >> 10)
287 #define SWP_ENTRY(type, offset)	((swp_entry_t) { (type) | ((offset) << 10) })
288 #define pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
289 #define swp_entry_to_pte(x)	((pte_t) { (x).val })
290 
291 /*
292  * Routines for update of PTE
293  *
294  * We just can use generic implementation, as SuperH has no SMP feature.
295  * (We needed atomic implementation for SMP)
296  *
297  */
298 
299 #define pte_same(A,B)	(pte_val(A) == pte_val(B))
300 
301 #endif /* !__ASSEMBLY__ */
302 
303 /* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
304 #define PageSkip(page)		(0)
305 #define kern_addr_valid(addr)	(1)
306 
307 #define io_remap_page_range remap_page_range
308 
309 /*
310  * No page table caches to initialise
311  */
312 #define pgtable_cache_init()	do { } while (0)
313 
314 /*
315  * Set pg flags to non-cached
316  */
317 #define pgprot_noncached(_prot) __pgprot(pgprot_val(_prot) &= ~_PAGE_CACHABLE)
318 
319 
320 #endif /* __ASM_SH_PAGE_H */
321