1 #ifndef _PARISC_PGTABLE_H
2 #define _PARISC_PGTABLE_H
3 
4 #include <asm/fixmap.h>
5 
6 #ifndef __ASSEMBLY__
7 /*
8  * we simulate an x86-style page table for the linux mm code
9  */
10 
11 #include <linux/spinlock.h>
12 #include <asm/processor.h>
13 #include <asm/cache.h>
14 #include <asm/bitops.h>
15 
16 #define ARCH_STACK_GROWSUP
17 
18 /*
19  * kern_addr_valid(ADDR) tests if ADDR is pointing to valid kernel
20  * memory.  For the return value to be meaningful, ADDR must be >=
21  * PAGE_OFFSET.  This operation can be relatively expensive (e.g.,
22  * require a hash-, or multi-level tree-lookup or something of that
23  * sort) but it guarantees to return TRUE only if accessing the page
24  * at that address does not cause an error.  Note that there may be
25  * addresses for which kern_addr_valid() returns FALSE even though an
26  * access would not cause an error (e.g., this is typically true for
27  * memory mapped I/O regions.
28  *
29  * XXX Need to implement this for parisc.
30  */
31 #define kern_addr_valid(addr)	(1)
32 
33 /* Certain architectures need to do special things when PTEs
34  * within a page table are directly modified.  Thus, the following
35  * hook is made available.
36  */
37 #define set_pte(pteptr, pteval)                                 \
38         do{                                                     \
39                 *(pteptr) = (pteval);                           \
40         } while(0)
41 
42 #endif /* !__ASSEMBLY__ */
43 
44 #define pte_ERROR(e) \
45 	printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
46 #define pmd_ERROR(e) \
47 	printk("%s:%d: bad pmd %08lx.\n", __FILE__, __LINE__, pmd_val(e))
48 #define pgd_ERROR(e) \
49 	printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
50 
51  /* Note: If you change ISTACK_SIZE, you need to change the corresponding
52   * values in vmlinux.lds and vmlinux64.lds (init_istack section). Also,
53   * the "order" and size need to agree.
54   */
55 
56 #define  ISTACK_SIZE  32768 /* Interrupt Stack Size */
57 #define  ISTACK_ORDER 3
58 
59 /*
60  * NOTE: Many of the below macros use PT_NLEVELS because
61  *       it is convenient that PT_NLEVELS == LOG2(pte size in bytes),
62  *       i.e. we use 3 level page tables when we use 8 byte pte's
63  *       (for 64 bit) and 2 level page tables when we use 4 byte pte's
64  */
65 
66 #ifdef __LP64__
67 #define PT_NLEVELS 3
68 #define PT_INITIAL 4 /* Number of initial page tables */
69 #else
70 #define PT_NLEVELS 2
71 #define PT_INITIAL 2 /* Number of initial page tables */
72 #endif
73 
74 #define MAX_ADDRBITS (PAGE_SHIFT + (PT_NLEVELS)*(PAGE_SHIFT - PT_NLEVELS))
75 #define MAX_ADDRESS (1UL << MAX_ADDRBITS)
76 
77 #define SPACEID_SHIFT (MAX_ADDRBITS - 32)
78 
79 /* Definitions for 1st level */
80 
81 #define PGDIR_SHIFT  (PAGE_SHIFT + (PT_NLEVELS - 1)*(PAGE_SHIFT - PT_NLEVELS))
82 #define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
83 #define PGDIR_MASK	(~(PGDIR_SIZE-1))
84 #define PTRS_PER_PGD    (1UL << (PAGE_SHIFT - PT_NLEVELS))
85 #define USER_PTRS_PER_PGD       PTRS_PER_PGD
86 
87 /* Definitions for 2nd level */
88 #define pgtable_cache_init()	do { } while (0)
89 
90 #define PMD_SHIFT       (PAGE_SHIFT + (PAGE_SHIFT - PT_NLEVELS))
91 #define PMD_SIZE	(1UL << PMD_SHIFT)
92 #define PMD_MASK	(~(PMD_SIZE-1))
93 #if PT_NLEVELS == 3
94 #define PTRS_PER_PMD    (1UL << (PAGE_SHIFT - PT_NLEVELS))
95 #else
96 #define PTRS_PER_PMD    1
97 #endif
98 
99 /* Definitions for 3rd level */
100 
101 #define PTRS_PER_PTE    (1UL << (PAGE_SHIFT - PT_NLEVELS))
102 
103 /*
104  * pgd entries used up by user/kernel:
105  */
106 
107 #define FIRST_USER_PGD_NR	0
108 
109 #ifndef __ASSEMBLY__
110 extern  void *vmalloc_start;
111 #define PCXL_DMA_MAP_SIZE   (8*1024*1024)
112 #define VMALLOC_START   ((unsigned long)vmalloc_start)
113 #define VMALLOC_VMADDR(x) ((unsigned long)(x))
114 #define VMALLOC_END	(FIXADDR_START)
115 #endif
116 
117 /* NB: The tlb miss handlers make certain assumptions about the order */
118 /*     of the following bits, so be careful (One example, bits 25-31  */
119 /*     are moved together in one instruction).                        */
120 
121 #define _PAGE_READ_BIT     31   /* (0x001) read access allowed */
122 #define _PAGE_WRITE_BIT    30   /* (0x002) write access allowed */
123 #define _PAGE_EXEC_BIT     29   /* (0x004) execute access allowed */
124 #define _PAGE_GATEWAY_BIT  28   /* (0x008) privilege promotion allowed */
125 #define _PAGE_DMB_BIT      27   /* (0x010) Data Memory Break enable (B bit) */
126 #define _PAGE_DIRTY_BIT    26   /* (0x020) Page Dirty (D bit) */
127 #define _PAGE_REFTRAP_BIT  25   /* (0x040) Page Ref. Trap enable (T bit) */
128 #define _PAGE_NO_CACHE_BIT 24   /* (0x080) Uncached Page (U bit) */
129 #define _PAGE_ACCESSED_BIT 23   /* (0x100) Software: Page Accessed */
130 #define _PAGE_PRESENT_BIT  22   /* (0x200) Software: translation valid */
131 #define _PAGE_FLUSH_BIT    21   /* (0x400) Software: translation valid */
132 				/*             for cache flushing only */
133 #define _PAGE_USER_BIT     20   /* (0x800) Software: User accessable page */
134 
135 /* N.B. The bits are defined in terms of a 32 bit word above, so the */
136 /*      following macro is ok for both 32 and 64 bit.                */
137 
138 #define xlate_pabit(x) (31 - x)
139 
140 #define _PAGE_READ     (1 << xlate_pabit(_PAGE_READ_BIT))
141 #define _PAGE_WRITE    (1 << xlate_pabit(_PAGE_WRITE_BIT))
142 #define _PAGE_RW       (_PAGE_READ | _PAGE_WRITE)
143 #define _PAGE_EXEC     (1 << xlate_pabit(_PAGE_EXEC_BIT))
144 #define _PAGE_GATEWAY  (1 << xlate_pabit(_PAGE_GATEWAY_BIT))
145 #define _PAGE_DMB      (1 << xlate_pabit(_PAGE_DMB_BIT))
146 #define _PAGE_DIRTY    (1 << xlate_pabit(_PAGE_DIRTY_BIT))
147 #define _PAGE_REFTRAP  (1 << xlate_pabit(_PAGE_REFTRAP_BIT))
148 #define _PAGE_NO_CACHE (1 << xlate_pabit(_PAGE_NO_CACHE_BIT))
149 #define _PAGE_ACCESSED (1 << xlate_pabit(_PAGE_ACCESSED_BIT))
150 #define _PAGE_PRESENT  (1 << xlate_pabit(_PAGE_PRESENT_BIT))
151 #define _PAGE_FLUSH    (1 << xlate_pabit(_PAGE_FLUSH_BIT))
152 #define _PAGE_USER     (1 << xlate_pabit(_PAGE_USER_BIT))
153 
154 #define _PAGE_TABLE	(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE |  _PAGE_DIRTY | _PAGE_ACCESSED)
155 #define _PAGE_CHG_MASK	(PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
156 #define _PAGE_KERNEL	(_PAGE_PRESENT | _PAGE_EXEC | _PAGE_READ | _PAGE_WRITE | _PAGE_DIRTY | _PAGE_ACCESSED)
157 
158 #ifndef __ASSEMBLY__
159 
160 #define PAGE_NONE	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
161 #define PAGE_SHARED	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_WRITE | _PAGE_ACCESSED)
162 /* Others seem to make this executable, I don't know if that's correct
163    or not.  The stack is mapped this way though so this is necessary
164    in the short term - dhd@linuxcare.com, 2000-08-08 */
165 #define PAGE_READONLY	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_ACCESSED)
166 #define PAGE_WRITEONLY  __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_WRITE | _PAGE_ACCESSED)
167 #define PAGE_EXECREAD   __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_EXEC |_PAGE_ACCESSED)
168 #define PAGE_COPY       PAGE_EXECREAD
169 #define PAGE_RWX        __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_WRITE | _PAGE_EXEC |_PAGE_ACCESSED)
170 #define PAGE_KERNEL	__pgprot(_PAGE_KERNEL)
171 #define PAGE_KERNEL_RO	__pgprot(_PAGE_PRESENT | _PAGE_EXEC | _PAGE_READ | _PAGE_DIRTY | _PAGE_ACCESSED)
172 #define PAGE_KERNEL_UNC	__pgprot(_PAGE_KERNEL | _PAGE_NO_CACHE)
173 #define PAGE_GATEWAY    __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED | _PAGE_GATEWAY| _PAGE_READ)
174 #define PAGE_FLUSH      __pgprot(_PAGE_FLUSH)
175 
176 
177 /*
178  * We could have an execute only page using "gateway - promote to priv
179  * level 3", but that is kind of silly. So, the way things are defined
180  * now, we must always have read permission for pages with execute
181  * permission. For the fun of it we'll go ahead and support write only
182  * pages.
183  */
184 
185 	 /*xwr*/
186 #define __P000  PAGE_NONE
187 #define __P001  PAGE_READONLY
188 #define __P010  __P000 /* copy on write */
189 #define __P011  __P001 /* copy on write */
190 #define __P100  PAGE_EXECREAD
191 #define __P101  PAGE_EXECREAD
192 #define __P110  __P100 /* copy on write */
193 #define __P111  __P101 /* copy on write */
194 
195 #define __S000  PAGE_NONE
196 #define __S001  PAGE_READONLY
197 #define __S010  PAGE_WRITEONLY
198 #define __S011  PAGE_SHARED
199 #define __S100  PAGE_EXECREAD
200 #define __S101  PAGE_EXECREAD
201 #define __S110  PAGE_RWX
202 #define __S111  PAGE_RWX
203 
204 extern pgd_t swapper_pg_dir[]; /* declared in init_task.c */
205 
206 /* initial page tables for 0-8MB for kernel */
207 
208 extern unsigned long pg0[];
209 
210 /* zero page used for uninitialized stuff */
211 
212 extern unsigned long *empty_zero_page;
213 
214 /*
215  * ZERO_PAGE is a global shared page that is always zero: used
216  * for zero-mapped memory areas etc..
217  */
218 
219 #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
220 
221 #define pte_none(x)     ((pte_val(x) == 0) || (pte_val(x) & _PAGE_FLUSH))
222 #define pte_present(x)	(pte_val(x) & _PAGE_PRESENT)
223 #define pte_clear(xp)	do { pte_val(*(xp)) = 0; } while (0)
224 
225 #define pmd_none(x)	(!pmd_val(x))
226 #define pmd_bad(x)	((pmd_val(x) & ~PAGE_MASK) != _PAGE_TABLE)
227 #define pmd_present(x)	(pmd_val(x) & _PAGE_PRESENT)
228 #define pmd_clear(xp)	do { pmd_val(*(xp)) = 0; } while (0)
229 
230 
231 
232 #ifdef __LP64__
233 #define pgd_page(pgd) ((unsigned long) __va(pgd_val(pgd) & PAGE_MASK))
234 
235 /* For 64 bit we have three level tables */
236 
237 #define pgd_none(x)     (!pgd_val(x))
238 #define pgd_bad(x)      ((pgd_val(x) & ~PAGE_MASK) != _PAGE_TABLE)
239 #define pgd_present(x)  (pgd_val(x) & _PAGE_PRESENT)
240 #define pgd_clear(xp)   do { pgd_val(*(xp)) = 0; } while (0)
241 #else
242 /*
243  * The "pgd_xxx()" functions here are trivial for a folded two-level
244  * setup: the pgd is never bad, and a pmd always exists (as it's folded
245  * into the pgd entry)
246  */
pgd_none(pgd_t pgd)247 extern inline int pgd_none(pgd_t pgd)		{ return 0; }
pgd_bad(pgd_t pgd)248 extern inline int pgd_bad(pgd_t pgd)		{ return 0; }
pgd_present(pgd_t pgd)249 extern inline int pgd_present(pgd_t pgd)	{ return 1; }
pgd_clear(pgd_t * pgdp)250 extern inline void pgd_clear(pgd_t * pgdp)	{ }
251 #endif
252 
253 /*
254  * The following only work if pte_present() is true.
255  * Undefined behaviour if not..
256  */
pte_read(pte_t pte)257 extern inline int pte_read(pte_t pte)		{ return pte_val(pte) & _PAGE_READ; }
pte_dirty(pte_t pte)258 extern inline int pte_dirty(pte_t pte)		{ return pte_val(pte) & _PAGE_DIRTY; }
pte_young(pte_t pte)259 extern inline int pte_young(pte_t pte)		{ return pte_val(pte) & _PAGE_ACCESSED; }
pte_write(pte_t pte)260 extern inline int pte_write(pte_t pte)		{ return pte_val(pte) & _PAGE_WRITE; }
261 
pte_rdprotect(pte_t pte)262 extern inline pte_t pte_rdprotect(pte_t pte)	{ pte_val(pte) &= ~_PAGE_READ; return pte; }
pte_mkclean(pte_t pte)263 extern inline pte_t pte_mkclean(pte_t pte)	{ pte_val(pte) &= ~_PAGE_DIRTY; return pte; }
pte_mkold(pte_t pte)264 extern inline pte_t pte_mkold(pte_t pte)	{ pte_val(pte) &= ~_PAGE_ACCESSED; return pte; }
pte_wrprotect(pte_t pte)265 extern inline pte_t pte_wrprotect(pte_t pte)	{ pte_val(pte) &= ~_PAGE_WRITE; return pte; }
pte_mkread(pte_t pte)266 extern inline pte_t pte_mkread(pte_t pte)	{ pte_val(pte) |= _PAGE_READ; return pte; }
pte_mkdirty(pte_t pte)267 extern inline pte_t pte_mkdirty(pte_t pte)	{ pte_val(pte) |= _PAGE_DIRTY; return pte; }
pte_mkyoung(pte_t pte)268 extern inline pte_t pte_mkyoung(pte_t pte)	{ pte_val(pte) |= _PAGE_ACCESSED; return pte; }
pte_mkwrite(pte_t pte)269 extern inline pte_t pte_mkwrite(pte_t pte)	{ pte_val(pte) |= _PAGE_WRITE; return pte; }
270 
271 /*
272  * Conversion functions: convert a page and protection to a page entry,
273  * and a page entry and page directory to the page they refer to.
274  */
275 #define __mk_pte(addr,pgprot) \
276 ({									\
277 	pte_t __pte;							\
278 									\
279 	pte_val(__pte) = ((addr)+pgprot_val(pgprot));			\
280 									\
281 	__pte;								\
282 })
283 
284 /*
285  * Change "struct page" to physical address.
286  */
287 #define page_to_phys(page)      PAGE_TO_PA(page)
288 
289 #ifdef CONFIG_DISCONTIGMEM
290 #define PAGE_TO_PA(page) \
291 		((((page)-(page)->zone->zone_mem_map) << PAGE_SHIFT) \
292 		+ ((page)->zone->zone_start_paddr))
293 #else
294 #define PAGE_TO_PA(page) ((page - mem_map) << PAGE_SHIFT)
295 #endif
296 
297 #define mk_pte(page, pgprot)						\
298 ({									\
299 	pte_t __pte;                                                    \
300 									\
301 	pte_val(__pte) = ((unsigned long)(PAGE_TO_PA(page))) |		\
302 						pgprot_val(pgprot);	\
303 									\
304 	__pte;								\
305 })
306 
307 /* This takes a physical page address that is used by the remapping functions */
308 #define mk_pte_phys(physpage, pgprot) \
309 ({ pte_t __pte; pte_val(__pte) = physpage + pgprot_val(pgprot); __pte; })
310 
pte_modify(pte_t pte,pgprot_t newprot)311 extern inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
312 { pte_val(pte) = (pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot); return pte; }
313 
314 /* Permanent address of a page.  On parisc we don't have highmem. */
315 
316 #ifdef CONFIG_DISCONTIGMEM
317 #define pte_page(x) (phys_to_page(pte_val(x)))
318 #else
319 #define pte_page(x) (mem_map+(pte_val(x) >> PAGE_SHIFT))
320 #endif
321 
322 
323 #define pmd_page(pmd) ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
324 
325 #define pgd_index(address) ((address) >> PGDIR_SHIFT)
326 
327 /* to find an entry in a page-table-directory */
328 #define pgd_offset(mm, address) \
329 ((mm)->pgd + ((address) >> PGDIR_SHIFT))
330 
331 /* to find an entry in a kernel page-table-directory */
332 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
333 
334 /* Find an entry in the second-level page table.. */
335 
336 #ifdef __LP64__
337 #define pmd_offset(dir,address) \
338 ((pmd_t *) pgd_page(*(dir)) + (((address)>>PMD_SHIFT) & (PTRS_PER_PMD-1)))
339 #else
340 #define pmd_offset(dir,addr) ((pmd_t *) dir)
341 #endif
342 
343 /* Find an entry in the third-level page table.. */
344 #define pte_offset(pmd, address) \
345 ((pte_t *) pmd_page(*(pmd)) + (((address)>>PAGE_SHIFT) & (PTRS_PER_PTE-1)))
346 
347 extern void paging_init (void);
348 
349 /* Used for deferring calls to flush_dcache_page() */
350 
351 #define PG_dcache_dirty         PG_arch_1
352 
353 struct vm_area_struct; /* forward declaration (include/linux/mm.h) */
354 extern void update_mmu_cache(struct vm_area_struct *, unsigned long, pte_t);
355 
356 /* Encode and de-code a swap entry */
357 
358 #define SWP_TYPE(x)                     ((x).val & 0x1f)
359 #define SWP_OFFSET(x)                   ( (((x).val >> 5) &  0xf) | \
360 					  (((x).val >> 7) & ~0xf) )
361 #define SWP_ENTRY(type, offset)         ((swp_entry_t) { (type) | \
362 					    ((offset &  0xf) << 5) | \
363 					    ((offset & ~0xf) << 7) })
364 #define pte_to_swp_entry(pte)		((swp_entry_t) { pte_val(pte) })
365 #define swp_entry_to_pte(x)		((pte_t) { (x).val })
366 
ptep_test_and_clear_young(pte_t * ptep)367 static inline int ptep_test_and_clear_young(pte_t *ptep)
368 {
369 #ifdef CONFIG_SMP
370 	return test_and_clear_bit(xlate_pabit(_PAGE_ACCESSED_BIT), ptep);
371 #else
372 	pte_t pte = *ptep;
373 	if (!pte_young(pte))
374 		return 0;
375 	set_pte(ptep, pte_mkold(pte));
376 	return 1;
377 #endif
378 }
379 
ptep_test_and_clear_dirty(pte_t * ptep)380 static inline int ptep_test_and_clear_dirty(pte_t *ptep)
381 {
382 #ifdef CONFIG_SMP
383 	return test_and_clear_bit(xlate_pabit(_PAGE_DIRTY_BIT), ptep);
384 #else
385 	pte_t pte = *ptep;
386 	if (!pte_dirty(pte))
387 		return 0;
388 	set_pte(ptep, pte_mkclean(pte));
389 	return 1;
390 #endif
391 }
392 
393 #ifdef CONFIG_SMP
394 extern spinlock_t pa_dbit_lock;
395 #else
396 static int pa_dbit_lock; /* dummy to keep the compilers happy */
397 #endif
398 
ptep_get_and_clear(pte_t * ptep)399 static inline pte_t ptep_get_and_clear(pte_t *ptep)
400 {
401 	pte_t old_pte;
402 	pte_t pte;
403 
404 	spin_lock(&pa_dbit_lock);
405 	pte = old_pte = *ptep;
406 	pte_val(pte) &= ~_PAGE_PRESENT;
407 	pte_val(pte) |= _PAGE_FLUSH;
408 	set_pte(ptep,pte);
409 	spin_unlock(&pa_dbit_lock);
410 
411 	return old_pte;
412 }
413 
ptep_set_wrprotect(pte_t * ptep)414 static inline void ptep_set_wrprotect(pte_t *ptep)
415 {
416 #ifdef CONFIG_SMP
417 	unsigned long new, old;
418 
419 	do {
420 		old = pte_val(*ptep);
421 		new = pte_val(pte_wrprotect(__pte (old)));
422 	} while (cmpxchg((unsigned long *) ptep, old, new) != old);
423 #else
424 	pte_t old_pte = *ptep;
425 	set_pte(ptep, pte_wrprotect(old_pte));
426 #endif
427 }
428 
ptep_mkdirty(pte_t * ptep)429 static inline void ptep_mkdirty(pte_t *ptep)
430 {
431 #ifdef CONFIG_SMP
432 	set_bit(xlate_pabit(_PAGE_DIRTY_BIT), ptep);
433 #else
434 	pte_t old_pte = *ptep;
435 	set_pte(ptep, pte_mkdirty(old_pte));
436 #endif
437 }
438 
439 #define pte_same(A,B)	(pte_val(A) == pte_val(B))
440 
441 
442 #endif /* !__ASSEMBLY__ */
443 
444 /* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
445 #define PageSkip(page)		(0)
446 
447 #define io_remap_page_range remap_page_range
448 
449 /* We provide our own get_unmapped_area to provide cache coherency */
450 
451 #define HAVE_ARCH_UNMAPPED_AREA
452 
453 #endif /* _PARISC_PGTABLE_H */
454