xref: /openbmc/linux/arch/parisc/include/asm/pgtable.h (revision b830f94f)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _PARISC_PGTABLE_H
3 #define _PARISC_PGTABLE_H
4 
5 #include <asm-generic/4level-fixup.h>
6 
7 #include <asm/fixmap.h>
8 
9 #ifndef __ASSEMBLY__
10 /*
11  * we simulate an x86-style page table for the linux mm code
12  */
13 
14 #include <linux/bitops.h>
15 #include <linux/spinlock.h>
16 #include <linux/mm_types.h>
17 #include <asm/processor.h>
18 #include <asm/cache.h>
19 
20 static inline spinlock_t *pgd_spinlock(pgd_t *);
21 
22 /*
23  * kern_addr_valid(ADDR) tests if ADDR is pointing to valid kernel
24  * memory.  For the return value to be meaningful, ADDR must be >=
25  * PAGE_OFFSET.  This operation can be relatively expensive (e.g.,
26  * require a hash-, or multi-level tree-lookup or something of that
27  * sort) but it guarantees to return TRUE only if accessing the page
28  * at that address does not cause an error.  Note that there may be
29  * addresses for which kern_addr_valid() returns FALSE even though an
30  * access would not cause an error (e.g., this is typically true for
31  * memory mapped I/O regions.
32  *
33  * XXX Need to implement this for parisc.
34  */
35 #define kern_addr_valid(addr)	(1)
36 
37 /* This is for the serialization of PxTLB broadcasts. At least on the N class
38  * systems, only one PxTLB inter processor broadcast can be active at any one
39  * time on the Merced bus.
40 
41  * PTE updates are protected by locks in the PMD.
42  */
43 extern spinlock_t pa_tlb_flush_lock;
44 extern spinlock_t pa_swapper_pg_lock;
45 #if defined(CONFIG_64BIT) && defined(CONFIG_SMP)
46 extern int pa_serialize_tlb_flushes;
47 #else
48 #define pa_serialize_tlb_flushes        (0)
49 #endif
50 
51 #define purge_tlb_start(flags)  do { \
52 	if (pa_serialize_tlb_flushes)	\
53 		spin_lock_irqsave(&pa_tlb_flush_lock, flags); \
54 	else \
55 		local_irq_save(flags);	\
56 	} while (0)
57 #define purge_tlb_end(flags)	do { \
58 	if (pa_serialize_tlb_flushes)	\
59 		spin_unlock_irqrestore(&pa_tlb_flush_lock, flags); \
60 	else \
61 		local_irq_restore(flags); \
62 	} while (0)
63 
64 /* Purge data and instruction TLB entries. The TLB purge instructions
65  * are slow on SMP machines since the purge must be broadcast to all CPUs.
66  */
67 
68 static inline void purge_tlb_entries(struct mm_struct *mm, unsigned long addr)
69 {
70 	unsigned long flags;
71 
72 	purge_tlb_start(flags);
73 	mtsp(mm->context, 1);
74 	pdtlb(addr);
75 	pitlb(addr);
76 	purge_tlb_end(flags);
77 }
78 
79 /* Certain architectures need to do special things when PTEs
80  * within a page table are directly modified.  Thus, the following
81  * hook is made available.
82  */
83 #define set_pte(pteptr, pteval)                                 \
84         do{                                                     \
85                 *(pteptr) = (pteval);                           \
86         } while(0)
87 
88 #define set_pte_at(mm, addr, ptep, pteval)			\
89 	do {							\
90 		pte_t old_pte;					\
91 		unsigned long flags;				\
92 		spin_lock_irqsave(pgd_spinlock((mm)->pgd), flags);\
93 		old_pte = *ptep;				\
94 		set_pte(ptep, pteval);				\
95 		purge_tlb_entries(mm, addr);			\
96 		spin_unlock_irqrestore(pgd_spinlock((mm)->pgd), flags);\
97 	} while (0)
98 
99 #endif /* !__ASSEMBLY__ */
100 
101 #include <asm/page.h>
102 
103 #define pte_ERROR(e) \
104 	printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
105 #define pmd_ERROR(e) \
106 	printk("%s:%d: bad pmd %08lx.\n", __FILE__, __LINE__, (unsigned long)pmd_val(e))
107 #define pgd_ERROR(e) \
108 	printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, (unsigned long)pgd_val(e))
109 
110 /* This is the size of the initially mapped kernel memory */
111 #if defined(CONFIG_64BIT)
112 #define KERNEL_INITIAL_ORDER	26	/* 1<<26 = 64MB */
113 #else
114 #define KERNEL_INITIAL_ORDER	25	/* 1<<25 = 32MB */
115 #endif
116 #define KERNEL_INITIAL_SIZE	(1 << KERNEL_INITIAL_ORDER)
117 
118 #if CONFIG_PGTABLE_LEVELS == 3
119 #define PGD_ORDER	1 /* Number of pages per pgd */
120 #define PMD_ORDER	1 /* Number of pages per pmd */
121 #define PGD_ALLOC_ORDER	(2 + 1) /* first pgd contains pmd */
122 #else
123 #define PGD_ORDER	1 /* Number of pages per pgd */
124 #define PGD_ALLOC_ORDER	(PGD_ORDER + 1)
125 #endif
126 
127 /* Definitions for 3rd level (we use PLD here for Page Lower directory
128  * because PTE_SHIFT is used lower down to mean shift that has to be
129  * done to get usable bits out of the PTE) */
130 #define PLD_SHIFT	PAGE_SHIFT
131 #define PLD_SIZE	PAGE_SIZE
132 #define BITS_PER_PTE	(PAGE_SHIFT - BITS_PER_PTE_ENTRY)
133 #define PTRS_PER_PTE    (1UL << BITS_PER_PTE)
134 
135 /* Definitions for 2nd level */
136 #define pgtable_cache_init()	do { } while (0)
137 
138 #define PMD_SHIFT       (PLD_SHIFT + BITS_PER_PTE)
139 #define PMD_SIZE	(1UL << PMD_SHIFT)
140 #define PMD_MASK	(~(PMD_SIZE-1))
141 #if CONFIG_PGTABLE_LEVELS == 3
142 #define BITS_PER_PMD	(PAGE_SHIFT + PMD_ORDER - BITS_PER_PMD_ENTRY)
143 #else
144 #define __PAGETABLE_PMD_FOLDED 1
145 #define BITS_PER_PMD	0
146 #endif
147 #define PTRS_PER_PMD    (1UL << BITS_PER_PMD)
148 
149 /* Definitions for 1st level */
150 #define PGDIR_SHIFT	(PMD_SHIFT + BITS_PER_PMD)
151 #if (PGDIR_SHIFT + PAGE_SHIFT + PGD_ORDER - BITS_PER_PGD_ENTRY) > BITS_PER_LONG
152 #define BITS_PER_PGD	(BITS_PER_LONG - PGDIR_SHIFT)
153 #else
154 #define BITS_PER_PGD	(PAGE_SHIFT + PGD_ORDER - BITS_PER_PGD_ENTRY)
155 #endif
156 #define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
157 #define PGDIR_MASK	(~(PGDIR_SIZE-1))
158 #define PTRS_PER_PGD    (1UL << BITS_PER_PGD)
159 #define USER_PTRS_PER_PGD       PTRS_PER_PGD
160 
161 #ifdef CONFIG_64BIT
162 #define MAX_ADDRBITS	(PGDIR_SHIFT + BITS_PER_PGD)
163 #define MAX_ADDRESS	(1UL << MAX_ADDRBITS)
164 #define SPACEID_SHIFT	(MAX_ADDRBITS - 32)
165 #else
166 #define MAX_ADDRBITS	(BITS_PER_LONG)
167 #define MAX_ADDRESS	(1UL << MAX_ADDRBITS)
168 #define SPACEID_SHIFT	0
169 #endif
170 
171 /* This calculates the number of initial pages we need for the initial
172  * page tables */
173 #if (KERNEL_INITIAL_ORDER) >= (PMD_SHIFT)
174 # define PT_INITIAL	(1 << (KERNEL_INITIAL_ORDER - PMD_SHIFT))
175 #else
176 # define PT_INITIAL	(1)  /* all initial PTEs fit into one page */
177 #endif
178 
179 /*
180  * pgd entries used up by user/kernel:
181  */
182 
183 #define FIRST_USER_ADDRESS	0UL
184 
185 /* NB: The tlb miss handlers make certain assumptions about the order */
186 /*     of the following bits, so be careful (One example, bits 25-31  */
187 /*     are moved together in one instruction).                        */
188 
189 #define _PAGE_READ_BIT     31   /* (0x001) read access allowed */
190 #define _PAGE_WRITE_BIT    30   /* (0x002) write access allowed */
191 #define _PAGE_EXEC_BIT     29   /* (0x004) execute access allowed */
192 #define _PAGE_GATEWAY_BIT  28   /* (0x008) privilege promotion allowed */
193 #define _PAGE_DMB_BIT      27   /* (0x010) Data Memory Break enable (B bit) */
194 #define _PAGE_DIRTY_BIT    26   /* (0x020) Page Dirty (D bit) */
195 #define _PAGE_REFTRAP_BIT  25   /* (0x040) Page Ref. Trap enable (T bit) */
196 #define _PAGE_NO_CACHE_BIT 24   /* (0x080) Uncached Page (U bit) */
197 #define _PAGE_ACCESSED_BIT 23   /* (0x100) Software: Page Accessed */
198 #define _PAGE_PRESENT_BIT  22   /* (0x200) Software: translation valid */
199 #define _PAGE_HPAGE_BIT    21   /* (0x400) Software: Huge Page */
200 #define _PAGE_USER_BIT     20   /* (0x800) Software: User accessible page */
201 
202 /* N.B. The bits are defined in terms of a 32 bit word above, so the */
203 /*      following macro is ok for both 32 and 64 bit.                */
204 
205 #define xlate_pabit(x) (31 - x)
206 
207 /* this defines the shift to the usable bits in the PTE it is set so
208  * that the valid bits _PAGE_PRESENT_BIT and _PAGE_USER_BIT are set
209  * to zero */
210 #define PTE_SHIFT	   	xlate_pabit(_PAGE_USER_BIT)
211 
212 /* PFN_PTE_SHIFT defines the shift of a PTE value to access the PFN field */
213 #define PFN_PTE_SHIFT		12
214 
215 #define _PAGE_READ     (1 << xlate_pabit(_PAGE_READ_BIT))
216 #define _PAGE_WRITE    (1 << xlate_pabit(_PAGE_WRITE_BIT))
217 #define _PAGE_RW       (_PAGE_READ | _PAGE_WRITE)
218 #define _PAGE_EXEC     (1 << xlate_pabit(_PAGE_EXEC_BIT))
219 #define _PAGE_GATEWAY  (1 << xlate_pabit(_PAGE_GATEWAY_BIT))
220 #define _PAGE_DMB      (1 << xlate_pabit(_PAGE_DMB_BIT))
221 #define _PAGE_DIRTY    (1 << xlate_pabit(_PAGE_DIRTY_BIT))
222 #define _PAGE_REFTRAP  (1 << xlate_pabit(_PAGE_REFTRAP_BIT))
223 #define _PAGE_NO_CACHE (1 << xlate_pabit(_PAGE_NO_CACHE_BIT))
224 #define _PAGE_ACCESSED (1 << xlate_pabit(_PAGE_ACCESSED_BIT))
225 #define _PAGE_PRESENT  (1 << xlate_pabit(_PAGE_PRESENT_BIT))
226 #define _PAGE_HUGE     (1 << xlate_pabit(_PAGE_HPAGE_BIT))
227 #define _PAGE_USER     (1 << xlate_pabit(_PAGE_USER_BIT))
228 
229 #define _PAGE_TABLE	(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | _PAGE_DIRTY | _PAGE_ACCESSED)
230 #define _PAGE_CHG_MASK	(PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
231 #define _PAGE_KERNEL_RO	(_PAGE_PRESENT | _PAGE_READ | _PAGE_DIRTY | _PAGE_ACCESSED)
232 #define _PAGE_KERNEL_EXEC	(_PAGE_KERNEL_RO | _PAGE_EXEC)
233 #define _PAGE_KERNEL_RWX	(_PAGE_KERNEL_EXEC | _PAGE_WRITE)
234 #define _PAGE_KERNEL		(_PAGE_KERNEL_RO | _PAGE_WRITE)
235 
236 /* The pgd/pmd contains a ptr (in phys addr space); since all pgds/pmds
237  * are page-aligned, we don't care about the PAGE_OFFSET bits, except
238  * for a few meta-information bits, so we shift the address to be
239  * able to effectively address 40/42/44-bits of physical address space
240  * depending on 4k/16k/64k PAGE_SIZE */
241 #define _PxD_PRESENT_BIT   31
242 #define _PxD_ATTACHED_BIT  30
243 #define _PxD_VALID_BIT     29
244 
245 #define PxD_FLAG_PRESENT  (1 << xlate_pabit(_PxD_PRESENT_BIT))
246 #define PxD_FLAG_ATTACHED (1 << xlate_pabit(_PxD_ATTACHED_BIT))
247 #define PxD_FLAG_VALID    (1 << xlate_pabit(_PxD_VALID_BIT))
248 #define PxD_FLAG_MASK     (0xf)
249 #define PxD_FLAG_SHIFT    (4)
250 #define PxD_VALUE_SHIFT   (PFN_PTE_SHIFT-PxD_FLAG_SHIFT)
251 
252 #ifndef __ASSEMBLY__
253 
254 #define PAGE_NONE	__pgprot(_PAGE_PRESENT | _PAGE_USER)
255 #define PAGE_SHARED	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_WRITE)
256 /* Others seem to make this executable, I don't know if that's correct
257    or not.  The stack is mapped this way though so this is necessary
258    in the short term - dhd@linuxcare.com, 2000-08-08 */
259 #define PAGE_READONLY	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ)
260 #define PAGE_WRITEONLY  __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_WRITE)
261 #define PAGE_EXECREAD   __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_EXEC)
262 #define PAGE_COPY       PAGE_EXECREAD
263 #define PAGE_RWX        __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_WRITE | _PAGE_EXEC)
264 #define PAGE_KERNEL	__pgprot(_PAGE_KERNEL)
265 #define PAGE_KERNEL_EXEC	__pgprot(_PAGE_KERNEL_EXEC)
266 #define PAGE_KERNEL_RWX	__pgprot(_PAGE_KERNEL_RWX)
267 #define PAGE_KERNEL_RO	__pgprot(_PAGE_KERNEL_RO)
268 #define PAGE_KERNEL_UNC	__pgprot(_PAGE_KERNEL | _PAGE_NO_CACHE)
269 #define PAGE_GATEWAY    __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_GATEWAY| _PAGE_READ)
270 
271 
272 /*
273  * We could have an execute only page using "gateway - promote to priv
274  * level 3", but that is kind of silly. So, the way things are defined
275  * now, we must always have read permission for pages with execute
276  * permission. For the fun of it we'll go ahead and support write only
277  * pages.
278  */
279 
280 	 /*xwr*/
281 #define __P000  PAGE_NONE
282 #define __P001  PAGE_READONLY
283 #define __P010  __P000 /* copy on write */
284 #define __P011  __P001 /* copy on write */
285 #define __P100  PAGE_EXECREAD
286 #define __P101  PAGE_EXECREAD
287 #define __P110  __P100 /* copy on write */
288 #define __P111  __P101 /* copy on write */
289 
290 #define __S000  PAGE_NONE
291 #define __S001  PAGE_READONLY
292 #define __S010  PAGE_WRITEONLY
293 #define __S011  PAGE_SHARED
294 #define __S100  PAGE_EXECREAD
295 #define __S101  PAGE_EXECREAD
296 #define __S110  PAGE_RWX
297 #define __S111  PAGE_RWX
298 
299 
300 extern pgd_t swapper_pg_dir[]; /* declared in init_task.c */
301 
302 /* initial page tables for 0-8MB for kernel */
303 
304 extern pte_t pg0[];
305 
306 /* zero page used for uninitialized stuff */
307 
308 extern unsigned long *empty_zero_page;
309 
310 /*
311  * ZERO_PAGE is a global shared page that is always zero: used
312  * for zero-mapped memory areas etc..
313  */
314 
315 #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
316 
317 #define pte_none(x)     (pte_val(x) == 0)
318 #define pte_present(x)	(pte_val(x) & _PAGE_PRESENT)
319 #define pte_clear(mm, addr, xp)  set_pte_at(mm, addr, xp, __pte(0))
320 
321 #define pmd_flag(x)	(pmd_val(x) & PxD_FLAG_MASK)
322 #define pmd_address(x)	((unsigned long)(pmd_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)
323 #define pgd_flag(x)	(pgd_val(x) & PxD_FLAG_MASK)
324 #define pgd_address(x)	((unsigned long)(pgd_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)
325 
326 #if CONFIG_PGTABLE_LEVELS == 3
327 /* The first entry of the permanent pmd is not there if it contains
328  * the gateway marker */
329 #define pmd_none(x)	(!pmd_val(x) || pmd_flag(x) == PxD_FLAG_ATTACHED)
330 #else
331 #define pmd_none(x)	(!pmd_val(x))
332 #endif
333 #define pmd_bad(x)	(!(pmd_flag(x) & PxD_FLAG_VALID))
334 #define pmd_present(x)	(pmd_flag(x) & PxD_FLAG_PRESENT)
335 static inline void pmd_clear(pmd_t *pmd) {
336 #if CONFIG_PGTABLE_LEVELS == 3
337 	if (pmd_flag(*pmd) & PxD_FLAG_ATTACHED)
338 		/* This is the entry pointing to the permanent pmd
339 		 * attached to the pgd; cannot clear it */
340 		__pmd_val_set(*pmd, PxD_FLAG_ATTACHED);
341 	else
342 #endif
343 		__pmd_val_set(*pmd,  0);
344 }
345 
346 
347 
348 #if CONFIG_PGTABLE_LEVELS == 3
349 #define pgd_page_vaddr(pgd) ((unsigned long) __va(pgd_address(pgd)))
350 #define pgd_page(pgd)	virt_to_page((void *)pgd_page_vaddr(pgd))
351 
352 /* For 64 bit we have three level tables */
353 
354 #define pgd_none(x)     (!pgd_val(x))
355 #define pgd_bad(x)      (!(pgd_flag(x) & PxD_FLAG_VALID))
356 #define pgd_present(x)  (pgd_flag(x) & PxD_FLAG_PRESENT)
357 static inline void pgd_clear(pgd_t *pgd) {
358 #if CONFIG_PGTABLE_LEVELS == 3
359 	if(pgd_flag(*pgd) & PxD_FLAG_ATTACHED)
360 		/* This is the permanent pmd attached to the pgd; cannot
361 		 * free it */
362 		return;
363 #endif
364 	__pgd_val_set(*pgd, 0);
365 }
366 #else
367 /*
368  * The "pgd_xxx()" functions here are trivial for a folded two-level
369  * setup: the pgd is never bad, and a pmd always exists (as it's folded
370  * into the pgd entry)
371  */
372 static inline int pgd_none(pgd_t pgd)		{ return 0; }
373 static inline int pgd_bad(pgd_t pgd)		{ return 0; }
374 static inline int pgd_present(pgd_t pgd)	{ return 1; }
375 static inline void pgd_clear(pgd_t * pgdp)	{ }
376 #endif
377 
378 /*
379  * The following only work if pte_present() is true.
380  * Undefined behaviour if not..
381  */
382 static inline int pte_dirty(pte_t pte)		{ return pte_val(pte) & _PAGE_DIRTY; }
383 static inline int pte_young(pte_t pte)		{ return pte_val(pte) & _PAGE_ACCESSED; }
384 static inline int pte_write(pte_t pte)		{ return pte_val(pte) & _PAGE_WRITE; }
385 static inline int pte_special(pte_t pte)	{ return 0; }
386 
387 static inline pte_t pte_mkclean(pte_t pte)	{ pte_val(pte) &= ~_PAGE_DIRTY; return pte; }
388 static inline pte_t pte_mkold(pte_t pte)	{ pte_val(pte) &= ~_PAGE_ACCESSED; return pte; }
389 static inline pte_t pte_wrprotect(pte_t pte)	{ pte_val(pte) &= ~_PAGE_WRITE; return pte; }
390 static inline pte_t pte_mkdirty(pte_t pte)	{ pte_val(pte) |= _PAGE_DIRTY; return pte; }
391 static inline pte_t pte_mkyoung(pte_t pte)	{ pte_val(pte) |= _PAGE_ACCESSED; return pte; }
392 static inline pte_t pte_mkwrite(pte_t pte)	{ pte_val(pte) |= _PAGE_WRITE; return pte; }
393 static inline pte_t pte_mkspecial(pte_t pte)	{ return pte; }
394 
395 /*
396  * Huge pte definitions.
397  */
398 #ifdef CONFIG_HUGETLB_PAGE
399 #define pte_huge(pte)           (pte_val(pte) & _PAGE_HUGE)
400 #define pte_mkhuge(pte)         (__pte(pte_val(pte) | \
401 				 (parisc_requires_coherency() ? 0 : _PAGE_HUGE)))
402 #else
403 #define pte_huge(pte)           (0)
404 #define pte_mkhuge(pte)         (pte)
405 #endif
406 
407 
408 /*
409  * Conversion functions: convert a page and protection to a page entry,
410  * and a page entry and page directory to the page they refer to.
411  */
412 #define __mk_pte(addr,pgprot) \
413 ({									\
414 	pte_t __pte;							\
415 									\
416 	pte_val(__pte) = ((((addr)>>PAGE_SHIFT)<<PFN_PTE_SHIFT) + pgprot_val(pgprot));	\
417 									\
418 	__pte;								\
419 })
420 
421 #define mk_pte(page, pgprot)	pfn_pte(page_to_pfn(page), (pgprot))
422 
423 static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot)
424 {
425 	pte_t pte;
426 	pte_val(pte) = (pfn << PFN_PTE_SHIFT) | pgprot_val(pgprot);
427 	return pte;
428 }
429 
430 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
431 { pte_val(pte) = (pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot); return pte; }
432 
433 /* Permanent address of a page.  On parisc we don't have highmem. */
434 
435 #define pte_pfn(x)		(pte_val(x) >> PFN_PTE_SHIFT)
436 
437 #define pte_page(pte)		(pfn_to_page(pte_pfn(pte)))
438 
439 #define pmd_page_vaddr(pmd)	((unsigned long) __va(pmd_address(pmd)))
440 
441 #define __pmd_page(pmd) ((unsigned long) __va(pmd_address(pmd)))
442 #define pmd_page(pmd)	virt_to_page((void *)__pmd_page(pmd))
443 
444 #define pgd_index(address) ((address) >> PGDIR_SHIFT)
445 
446 /* to find an entry in a page-table-directory */
447 #define pgd_offset(mm, address) \
448 ((mm)->pgd + ((address) >> PGDIR_SHIFT))
449 
450 /* to find an entry in a kernel page-table-directory */
451 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
452 
453 /* Find an entry in the second-level page table.. */
454 
455 #if CONFIG_PGTABLE_LEVELS == 3
456 #define pmd_index(addr)         (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1))
457 #define pmd_offset(dir,address) \
458 ((pmd_t *) pgd_page_vaddr(*(dir)) + pmd_index(address))
459 #else
460 #define pmd_offset(dir,addr) ((pmd_t *) dir)
461 #endif
462 
463 /* Find an entry in the third-level page table.. */
464 #define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE-1))
465 #define pte_offset_kernel(pmd, address) \
466 	((pte_t *) pmd_page_vaddr(*(pmd)) + pte_index(address))
467 #define pte_offset_map(pmd, address) pte_offset_kernel(pmd, address)
468 #define pte_unmap(pte) do { } while (0)
469 
470 #define pte_unmap(pte)			do { } while (0)
471 #define pte_unmap_nested(pte)		do { } while (0)
472 
473 extern void paging_init (void);
474 
475 /* Used for deferring calls to flush_dcache_page() */
476 
477 #define PG_dcache_dirty         PG_arch_1
478 
479 extern void update_mmu_cache(struct vm_area_struct *, unsigned long, pte_t *);
480 
481 /* Encode and de-code a swap entry */
482 
483 #define __swp_type(x)                     ((x).val & 0x1f)
484 #define __swp_offset(x)                   ( (((x).val >> 6) &  0x7) | \
485 					  (((x).val >> 8) & ~0x7) )
486 #define __swp_entry(type, offset)         ((swp_entry_t) { (type) | \
487 					    ((offset &  0x7) << 6) | \
488 					    ((offset & ~0x7) << 8) })
489 #define __pte_to_swp_entry(pte)		((swp_entry_t) { pte_val(pte) })
490 #define __swp_entry_to_pte(x)		((pte_t) { (x).val })
491 
492 
493 static inline spinlock_t *pgd_spinlock(pgd_t *pgd)
494 {
495 	if (unlikely(pgd == swapper_pg_dir))
496 		return &pa_swapper_pg_lock;
497 	return (spinlock_t *)((char *)pgd + (PAGE_SIZE << (PGD_ALLOC_ORDER - 1)));
498 }
499 
500 
501 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
502 {
503 	pte_t pte;
504 	unsigned long flags;
505 
506 	if (!pte_young(*ptep))
507 		return 0;
508 
509 	spin_lock_irqsave(pgd_spinlock(vma->vm_mm->pgd), flags);
510 	pte = *ptep;
511 	if (!pte_young(pte)) {
512 		spin_unlock_irqrestore(pgd_spinlock(vma->vm_mm->pgd), flags);
513 		return 0;
514 	}
515 	set_pte(ptep, pte_mkold(pte));
516 	purge_tlb_entries(vma->vm_mm, addr);
517 	spin_unlock_irqrestore(pgd_spinlock(vma->vm_mm->pgd), flags);
518 	return 1;
519 }
520 
521 struct mm_struct;
522 static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
523 {
524 	pte_t old_pte;
525 	unsigned long flags;
526 
527 	spin_lock_irqsave(pgd_spinlock(mm->pgd), flags);
528 	old_pte = *ptep;
529 	set_pte(ptep, __pte(0));
530 	purge_tlb_entries(mm, addr);
531 	spin_unlock_irqrestore(pgd_spinlock(mm->pgd), flags);
532 
533 	return old_pte;
534 }
535 
536 static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
537 {
538 	unsigned long flags;
539 	spin_lock_irqsave(pgd_spinlock(mm->pgd), flags);
540 	set_pte(ptep, pte_wrprotect(*ptep));
541 	purge_tlb_entries(mm, addr);
542 	spin_unlock_irqrestore(pgd_spinlock(mm->pgd), flags);
543 }
544 
545 #define pte_same(A,B)	(pte_val(A) == pte_val(B))
546 
547 struct seq_file;
548 extern void arch_report_meminfo(struct seq_file *m);
549 
550 #endif /* !__ASSEMBLY__ */
551 
552 
553 /* TLB page size encoding - see table 3-1 in parisc20.pdf */
554 #define _PAGE_SIZE_ENCODING_4K		0
555 #define _PAGE_SIZE_ENCODING_16K		1
556 #define _PAGE_SIZE_ENCODING_64K		2
557 #define _PAGE_SIZE_ENCODING_256K	3
558 #define _PAGE_SIZE_ENCODING_1M		4
559 #define _PAGE_SIZE_ENCODING_4M		5
560 #define _PAGE_SIZE_ENCODING_16M		6
561 #define _PAGE_SIZE_ENCODING_64M		7
562 
563 #if defined(CONFIG_PARISC_PAGE_SIZE_4KB)
564 # define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_4K
565 #elif defined(CONFIG_PARISC_PAGE_SIZE_16KB)
566 # define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_16K
567 #elif defined(CONFIG_PARISC_PAGE_SIZE_64KB)
568 # define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_64K
569 #endif
570 
571 
572 #define pgprot_noncached(prot) __pgprot(pgprot_val(prot) | _PAGE_NO_CACHE)
573 
574 /* We provide our own get_unmapped_area to provide cache coherency */
575 
576 #define HAVE_ARCH_UNMAPPED_AREA
577 #define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
578 
579 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
580 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
581 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
582 #define __HAVE_ARCH_PTE_SAME
583 #include <asm-generic/pgtable.h>
584 
585 #endif /* _PARISC_PGTABLE_H */
586