1#ifdef __KERNEL__
2#ifndef _PPC_PGTABLE_H
3#define _PPC_PGTABLE_H
4
5#include <asm-generic/4level-fixup.h>
6
7
8#ifndef __ASSEMBLY__
9#include <linux/sched.h>
10#include <linux/threads.h>
11#include <asm/processor.h>		/* For TASK_SIZE */
12#include <asm/mmu.h>
13#include <asm/page.h>
14#include <asm/io.h>			/* For sub-arch specific PPC_PIN_SIZE */
15struct mm_struct;
16
17extern unsigned long va_to_phys(unsigned long address);
18extern pte_t *va_to_pte(unsigned long address);
19extern unsigned long ioremap_bot, ioremap_base;
20#endif /* __ASSEMBLY__ */
21
22/*
23 * The PowerPC MMU uses a hash table containing PTEs, together with
24 * a set of 16 segment registers (on 32-bit implementations), to define
25 * the virtual to physical address mapping.
26 *
27 * We use the hash table as an extended TLB, i.e. a cache of currently
28 * active mappings.  We maintain a two-level page table tree, much
29 * like that used by the i386, for the sake of the Linux memory
30 * management code.  Low-level assembler code in hashtable.S
31 * (procedure hash_page) is responsible for extracting ptes from the
32 * tree and putting them into the hash table when necessary, and
33 * updating the accessed and modified bits in the page table tree.
34 */
35
36/*
37 * The PowerPC MPC8xx uses a TLB with hardware assisted, software tablewalk.
38 * We also use the two level tables, but we can put the real bits in them
39 * needed for the TLB and tablewalk.  These definitions require Mx_CTR.PPM = 0,
40 * Mx_CTR.PPCS = 0, and MD_CTR.TWAM = 1.  The level 2 descriptor has
41 * additional page protection (when Mx_CTR.PPCS = 1) that allows TLB hit
42 * based upon user/super access.  The TLB does not have accessed nor write
43 * protect.  We assume that if the TLB get loaded with an entry it is
44 * accessed, and overload the changed bit for write protect.  We use
45 * two bits in the software pte that are supposed to be set to zero in
46 * the TLB entry (24 and 25) for these indicators.  Although the level 1
47 * descriptor contains the guarded and writethrough/copyback bits, we can
48 * set these at the page level since they get copied from the Mx_TWC
49 * register when the TLB entry is loaded.  We will use bit 27 for guard, since
50 * that is where it exists in the MD_TWC, and bit 26 for writethrough.
51 * These will get masked from the level 2 descriptor at TLB load time, and
52 * copied to the MD_TWC before it gets loaded.
53 * Large page sizes added.  We currently support two sizes, 4K and 8M.
54 * This also allows a TLB hander optimization because we can directly
55 * load the PMD into MD_TWC.  The 8M pages are only used for kernel
56 * mapping of well known areas.  The PMD (PGD) entries contain control
57 * flags in addition to the address, so care must be taken that the
58 * software no longer assumes these are only pointers.
59 */
60
61/*
62 * At present, all PowerPC 400-class processors share a similar TLB
63 * architecture. The instruction and data sides share a unified,
64 * 64-entry, fully-associative TLB which is maintained totally under
65 * software control. In addition, the instruction side has a
66 * hardware-managed, 4-entry, fully-associative TLB which serves as a
67 * first level to the shared TLB. These two TLBs are known as the UTLB
68 * and ITLB, respectively (see "mmu.h" for definitions).
69 */
70
71/*
72 * The normal case is that PTEs are 32-bits and we have a 1-page
73 * 1024-entry pgdir pointing to 1-page 1024-entry PTE pages.  -- paulus
74 *
75 * For any >32-bit physical address platform, we can use the following
76 * two level page table layout where the pgdir is 8KB and the MS 13 bits
77 * are an index to the second level table.  The combined pgdir/pmd first
78 * level has 2048 entries and the second level has 512 64-bit PTE entries.
79 * -Matt
80 */
81/* PMD_SHIFT determines the size of the area mapped by the PTE pages */
82#define PMD_SHIFT	(PAGE_SHIFT + PTE_SHIFT)
83#define PMD_SIZE	(1UL << PMD_SHIFT)
84#define PMD_MASK	(~(PMD_SIZE-1))
85
86/* PGDIR_SHIFT determines what a top-level page table entry can map */
87#define PGDIR_SHIFT	PMD_SHIFT
88#define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
89#define PGDIR_MASK	(~(PGDIR_SIZE-1))
90
91/*
92 * entries per page directory level: our page-table tree is two-level, so
93 * we don't really have any PMD directory.
94 */
95#define PTRS_PER_PTE	(1 << PTE_SHIFT)
96#define PTRS_PER_PMD	1
97#define PTRS_PER_PGD	(1 << (32 - PGDIR_SHIFT))
98
99#define USER_PTRS_PER_PGD	(TASK_SIZE / PGDIR_SIZE)
100#define FIRST_USER_ADDRESS	0
101
102#define USER_PGD_PTRS (PAGE_OFFSET >> PGDIR_SHIFT)
103#define KERNEL_PGD_PTRS (PTRS_PER_PGD-USER_PGD_PTRS)
104
105#define pte_ERROR(e) \
106	printk("%s:%d: bad pte "PTE_FMT".\n", __FILE__, __LINE__, pte_val(e))
107#define pmd_ERROR(e) \
108	printk("%s:%d: bad pmd %08lx.\n", __FILE__, __LINE__, pmd_val(e))
109#define pgd_ERROR(e) \
110	printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
111
112/*
113 * Just any arbitrary offset to the start of the vmalloc VM area: the
114 * current 64MB value just means that there will be a 64MB "hole" after the
115 * physical memory until the kernel virtual memory starts.  That means that
116 * any out-of-bounds memory accesses will hopefully be caught.
117 * The vmalloc() routines leaves a hole of 4kB between each vmalloced
118 * area for the same reason. ;)
119 *
120 * We no longer map larger than phys RAM with the BATs so we don't have
121 * to worry about the VMALLOC_OFFSET causing problems.  We do have to worry
122 * about clashes between our early calls to ioremap() that start growing down
123 * from ioremap_base being run into the VM area allocations (growing upwards
124 * from VMALLOC_START).  For this reason we have ioremap_bot to check when
125 * we actually run into our mappings setup in the early boot with the VM
126 * system.  This really does become a problem for machines with good amounts
127 * of RAM.  -- Cort
128 */
129#define VMALLOC_OFFSET (0x1000000) /* 16M */
130#ifdef PPC_PIN_SIZE
131#define VMALLOC_START (((_ALIGN((long)high_memory, PPC_PIN_SIZE) + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
132#else
133#define VMALLOC_START ((((long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
134#endif
135#define VMALLOC_END	ioremap_bot
136
137/*
138 * Bits in a linux-style PTE.  These match the bits in the
139 * (hardware-defined) PowerPC PTE as closely as possible.
140 */
141
142#if defined(CONFIG_40x)
143
144/* There are several potential gotchas here.  The 40x hardware TLBLO
145   field looks like this:
146
147   0  1  2  3  4  ... 18 19 20 21 22 23 24 25 26 27 28 29 30 31
148   RPN.....................  0  0 EX WR ZSEL.......  W  I  M  G
149
150   Where possible we make the Linux PTE bits match up with this
151
152   - bits 20 and 21 must be cleared, because we use 4k pages (40x can
153     support down to 1k pages), this is done in the TLBMiss exception
154     handler.
155   - We use only zones 0 (for kernel pages) and 1 (for user pages)
156     of the 16 available.  Bit 24-26 of the TLB are cleared in the TLB
157     miss handler.  Bit 27 is PAGE_USER, thus selecting the correct
158     zone.
159   - PRESENT *must* be in the bottom two bits because swap cache
160     entries use the top 30 bits.  Because 40x doesn't support SMP
161     anyway, M is irrelevant so we borrow it for PAGE_PRESENT.  Bit 30
162     is cleared in the TLB miss handler before the TLB entry is loaded.
163   - All other bits of the PTE are loaded into TLBLO without
164     modification, leaving us only the bits 20, 21, 24, 25, 26, 30 for
165     software PTE bits.  We actually use use bits 21, 24, 25, and
166     30 respectively for the software bits: ACCESSED, DIRTY, RW, and
167     PRESENT.
168*/
169
170/* Definitions for 40x embedded chips. */
171#define	_PAGE_GUARDED	0x001	/* G: page is guarded from prefetch */
172#define _PAGE_FILE	0x001	/* when !present: nonlinear file mapping */
173#define _PAGE_PRESENT	0x002	/* software: PTE contains a translation */
174#define	_PAGE_NO_CACHE	0x004	/* I: caching is inhibited */
175#define	_PAGE_WRITETHRU	0x008	/* W: caching is write-through */
176#define	_PAGE_USER	0x010	/* matches one of the zone permission bits */
177#define	_PAGE_RW	0x040	/* software: Writes permitted */
178#define	_PAGE_DIRTY	0x080	/* software: dirty page */
179#define _PAGE_HWWRITE	0x100	/* hardware: Dirty & RW, set in exception */
180#define _PAGE_HWEXEC	0x200	/* hardware: EX permission */
181#define _PAGE_ACCESSED	0x400	/* software: R: page referenced */
182
183#define _PMD_PRESENT	0x400	/* PMD points to page of PTEs */
184#define _PMD_BAD	0x802
185#define _PMD_SIZE	0x0e0	/* size field, != 0 for large-page PMD entry */
186#define _PMD_SIZE_4M	0x0c0
187#define _PMD_SIZE_16M	0x0e0
188#define PMD_PAGE_SIZE(pmdval)	(1024 << (((pmdval) & _PMD_SIZE) >> 4))
189
190#elif defined(CONFIG_44x)
191/*
192 * Definitions for PPC440
193 *
194 * Because of the 3 word TLB entries to support 36-bit addressing,
195 * the attribute are difficult to map in such a fashion that they
196 * are easily loaded during exception processing.  I decided to
197 * organize the entry so the ERPN is the only portion in the
198 * upper word of the PTE and the attribute bits below are packed
199 * in as sensibly as they can be in the area below a 4KB page size
200 * oriented RPN.  This at least makes it easy to load the RPN and
201 * ERPN fields in the TLB. -Matt
202 *
203 * Note that these bits preclude future use of a page size
204 * less than 4KB.
205 *
206 *
207 * PPC 440 core has following TLB attribute fields;
208 *
209 *   TLB1:
210 *   0  1  2  3  4  ... 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
211 *   RPN.................................  -  -  -  -  -  - ERPN.......
212 *
213 *   TLB2:
214 *   0  1  2  3  4  ... 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
215 *   -  -  -  -  -    - U0 U1 U2 U3 W  I  M  G  E   - UX UW UR SX SW SR
216 *
217 * There are some constrains and options, to decide mapping software bits
218 * into TLB entry.
219 *
220 *   - PRESENT *must* be in the bottom three bits because swap cache
221 *     entries use the top 29 bits for TLB2.
222 *
223 *   - FILE *must* be in the bottom three bits because swap cache
224 *     entries use the top 29 bits for TLB2.
225 *
226 *   - CACHE COHERENT bit (M) has no effect on PPC440 core, because it
227 *     doesn't support SMP. So we can use this as software bit, like
228 *     DIRTY.
229 *
230 * With the PPC 44x Linux implementation, the 0-11th LSBs of the PTE are used
231 * for memory protection related functions (see PTE structure in
232 * include/asm-ppc/mmu.h).  The _PAGE_XXX definitions in this file map to the
233 * above bits.  Note that the bit values are CPU specific, not architecture
234 * specific.
235 *
236 * The kernel PTE entry holds an arch-dependent swp_entry structure under
237 * certain situations. In other words, in such situations some portion of
238 * the PTE bits are used as a swp_entry. In the PPC implementation, the
239 * 3-24th LSB are shared with swp_entry, however the 0-2nd three LSB still
240 * hold protection values. That means the three protection bits are
241 * reserved for both PTE and SWAP entry at the most significant three
242 * LSBs.
243 *
244 * There are three protection bits available for SWAP entry:
245 *	_PAGE_PRESENT
246 *	_PAGE_FILE
247 *	_PAGE_HASHPTE (if HW has)
248 *
249 * So those three bits have to be inside of 0-2nd LSB of PTE.
250 *
251 */
252
253#define _PAGE_PRESENT	0x00000001		/* S: PTE valid */
254#define	_PAGE_RW	0x00000002		/* S: Write permission */
255#define _PAGE_FILE	0x00000004		/* S: nonlinear file mapping */
256#define _PAGE_ACCESSED	0x00000008		/* S: Page referenced */
257#define _PAGE_HWWRITE	0x00000010		/* H: Dirty & RW */
258#define _PAGE_HWEXEC	0x00000020		/* H: Execute permission */
259#define	_PAGE_USER	0x00000040		/* S: User page */
260#define	_PAGE_ENDIAN	0x00000080		/* H: E bit */
261#define	_PAGE_GUARDED	0x00000100		/* H: G bit */
262#define	_PAGE_DIRTY	0x00000200		/* S: Page dirty */
263#define	_PAGE_NO_CACHE	0x00000400		/* H: I bit */
264#define	_PAGE_WRITETHRU	0x00000800		/* H: W bit */
265
266/* TODO: Add large page lowmem mapping support */
267#define _PMD_PRESENT	0
268#define _PMD_PRESENT_MASK (PAGE_MASK)
269#define _PMD_BAD	(~PAGE_MASK)
270
271/* ERPN in a PTE never gets cleared, ignore it */
272#define _PTE_NONE_MASK	0xffffffff00000000ULL
273
274#elif defined(CONFIG_FSL_BOOKE)
275/*
276   MMU Assist Register 3:
277
278   32 33 34 35 36  ... 50 51 52 53 54 55 56 57 58 59 60 61 62 63
279   RPN......................  0  0 U0 U1 U2 U3 UX SX UW SW UR SR
280
281   - PRESENT *must* be in the bottom three bits because swap cache
282     entries use the top 29 bits.
283
284   - FILE *must* be in the bottom three bits because swap cache
285     entries use the top 29 bits.
286*/
287
288/* Definitions for FSL Book-E Cores */
289#define _PAGE_PRESENT	0x00001	/* S: PTE contains a translation */
290#define _PAGE_USER	0x00002	/* S: User page (maps to UR) */
291#define _PAGE_FILE	0x00002	/* S: when !present: nonlinear file mapping */
292#define _PAGE_ACCESSED	0x00004	/* S: Page referenced */
293#define _PAGE_HWWRITE	0x00008	/* H: Dirty & RW, set in exception */
294#define _PAGE_RW	0x00010	/* S: Write permission */
295#define _PAGE_HWEXEC	0x00020	/* H: UX permission */
296
297#define _PAGE_ENDIAN	0x00040	/* H: E bit */
298#define _PAGE_GUARDED	0x00080	/* H: G bit */
299#define _PAGE_COHERENT	0x00100	/* H: M bit */
300#define _PAGE_NO_CACHE	0x00200	/* H: I bit */
301#define _PAGE_WRITETHRU	0x00400	/* H: W bit */
302
303#ifdef CONFIG_PTE_64BIT
304#define _PAGE_DIRTY	0x08000	/* S: Page dirty */
305
306/* ERPN in a PTE never gets cleared, ignore it */
307#define _PTE_NONE_MASK	0xffffffffffff0000ULL
308#else
309#define _PAGE_DIRTY	0x00800	/* S: Page dirty */
310#endif
311
312#define _PMD_PRESENT	0
313#define _PMD_PRESENT_MASK (PAGE_MASK)
314#define _PMD_BAD	(~PAGE_MASK)
315
316#elif defined(CONFIG_8xx)
317/* Definitions for 8xx embedded chips. */
318#define _PAGE_PRESENT	0x0001	/* Page is valid */
319#define _PAGE_FILE	0x0002	/* when !present: nonlinear file mapping */
320#define _PAGE_NO_CACHE	0x0002	/* I: cache inhibit */
321#define _PAGE_SHARED	0x0004	/* No ASID (context) compare */
322
323/* These five software bits must be masked out when the entry is loaded
324 * into the TLB.
325 */
326#define _PAGE_EXEC	0x0008	/* software: i-cache coherency required */
327#define _PAGE_GUARDED	0x0010	/* software: guarded access */
328#define _PAGE_DIRTY	0x0020	/* software: page changed */
329#define _PAGE_RW	0x0040	/* software: user write access allowed */
330#define _PAGE_ACCESSED	0x0080	/* software: page referenced */
331
332/* Setting any bits in the nibble with the follow two controls will
333 * require a TLB exception handler change.  It is assumed unused bits
334 * are always zero.
335 */
336#define _PAGE_HWWRITE	0x0100	/* h/w write enable: never set in Linux PTE */
337#define _PAGE_USER	0x0800	/* One of the PP bits, the other is USER&~RW */
338
339#define _PMD_PRESENT	0x0001
340#define _PMD_BAD	0x0ff0
341#define _PMD_PAGE_MASK	0x000c
342#define _PMD_PAGE_8M	0x000c
343
344/*
345 * The 8xx TLB miss handler allegedly sets _PAGE_ACCESSED in the PTE
346 * for an address even if _PAGE_PRESENT is not set, as a performance
347 * optimization.  This is a bug if you ever want to use swap unless
348 * _PAGE_ACCESSED is 2, which it isn't, or unless you have 8xx-specific
349 * definitions for __swp_entry etc. below, which would be gross.
350 *  -- paulus
351 */
352#define _PTE_NONE_MASK _PAGE_ACCESSED
353
354#else /* CONFIG_6xx */
355/* Definitions for 60x, 740/750, etc. */
356#define _PAGE_PRESENT	0x001	/* software: pte contains a translation */
357#define _PAGE_HASHPTE	0x002	/* hash_page has made an HPTE for this pte */
358#define _PAGE_FILE	0x004	/* when !present: nonlinear file mapping */
359#define _PAGE_USER	0x004	/* usermode access allowed */
360#define _PAGE_GUARDED	0x008	/* G: prohibit speculative access */
361#define _PAGE_COHERENT	0x010	/* M: enforce memory coherence (SMP systems) */
362#define _PAGE_NO_CACHE	0x020	/* I: cache inhibit */
363#define _PAGE_WRITETHRU	0x040	/* W: cache write-through */
364#define _PAGE_DIRTY	0x080	/* C: page changed */
365#define _PAGE_ACCESSED	0x100	/* R: page referenced */
366#define _PAGE_EXEC	0x200	/* software: i-cache coherency required */
367#define _PAGE_RW	0x400	/* software: user write access allowed */
368
369#define _PTE_NONE_MASK	_PAGE_HASHPTE
370
371#define _PMD_PRESENT	0
372#define _PMD_PRESENT_MASK (PAGE_MASK)
373#define _PMD_BAD	(~PAGE_MASK)
374#endif
375
376/*
377 * Some bits are only used on some cpu families...
378 */
379#ifndef _PAGE_HASHPTE
380#define _PAGE_HASHPTE	0
381#endif
382#ifndef _PTE_NONE_MASK
383#define _PTE_NONE_MASK 0
384#endif
385#ifndef _PAGE_SHARED
386#define _PAGE_SHARED	0
387#endif
388#ifndef _PAGE_HWWRITE
389#define _PAGE_HWWRITE	0
390#endif
391#ifndef _PAGE_HWEXEC
392#define _PAGE_HWEXEC	0
393#endif
394#ifndef _PAGE_EXEC
395#define _PAGE_EXEC	0
396#endif
397#ifndef _PMD_PRESENT_MASK
398#define _PMD_PRESENT_MASK	_PMD_PRESENT
399#endif
400#ifndef _PMD_SIZE
401#define _PMD_SIZE	0
402#define PMD_PAGE_SIZE(pmd)	bad_call_to_PMD_PAGE_SIZE()
403#endif
404
405#define _PAGE_CHG_MASK	(PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
406
407/*
408 * Note: the _PAGE_COHERENT bit automatically gets set in the hardware
409 * PTE if CONFIG_SMP is defined (hash_page does this); there is no need
410 * to have it in the Linux PTE, and in fact the bit could be reused for
411 * another purpose.  -- paulus.
412 */
413
414#ifdef CONFIG_44x
415#define _PAGE_BASE	(_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_GUARDED)
416#else
417#define _PAGE_BASE	(_PAGE_PRESENT | _PAGE_ACCESSED)
418#endif
419#define _PAGE_WRENABLE	(_PAGE_RW | _PAGE_DIRTY | _PAGE_HWWRITE)
420#define _PAGE_KERNEL	(_PAGE_BASE | _PAGE_SHARED | _PAGE_WRENABLE)
421
422#ifdef CONFIG_PPC_STD_MMU
423/* On standard PPC MMU, no user access implies kernel read/write access,
424 * so to write-protect kernel memory we must turn on user access */
425#define _PAGE_KERNEL_RO	(_PAGE_BASE | _PAGE_SHARED | _PAGE_USER)
426#else
427#define _PAGE_KERNEL_RO	(_PAGE_BASE | _PAGE_SHARED)
428#endif
429
430#define _PAGE_IO	(_PAGE_KERNEL | _PAGE_NO_CACHE | _PAGE_GUARDED)
431#define _PAGE_RAM	(_PAGE_KERNEL | _PAGE_HWEXEC)
432
433#if defined(CONFIG_KGDB) || defined(CONFIG_XMON) || defined(CONFIG_BDI_SWITCH)
434/* We want the debuggers to be able to set breakpoints anywhere, so
435 * don't write protect the kernel text */
436#define _PAGE_RAM_TEXT	_PAGE_RAM
437#else
438#define _PAGE_RAM_TEXT	(_PAGE_KERNEL_RO | _PAGE_HWEXEC)
439#endif
440
441#define PAGE_NONE	__pgprot(_PAGE_BASE)
442#define PAGE_READONLY	__pgprot(_PAGE_BASE | _PAGE_USER)
443#define PAGE_READONLY_X	__pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC)
444#define PAGE_SHARED	__pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW)
445#define PAGE_SHARED_X	__pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW | _PAGE_EXEC)
446#define PAGE_COPY	__pgprot(_PAGE_BASE | _PAGE_USER)
447#define PAGE_COPY_X	__pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC)
448
449#define PAGE_KERNEL		__pgprot(_PAGE_RAM)
450#define PAGE_KERNEL_NOCACHE	__pgprot(_PAGE_IO)
451
452/*
453 * The PowerPC can only do execute protection on a segment (256MB) basis,
454 * not on a page basis.  So we consider execute permission the same as read.
455 * Also, write permissions imply read permissions.
456 * This is the closest we can get..
457 */
458#define __P000	PAGE_NONE
459#define __P001	PAGE_READONLY_X
460#define __P010	PAGE_COPY
461#define __P011	PAGE_COPY_X
462#define __P100	PAGE_READONLY
463#define __P101	PAGE_READONLY_X
464#define __P110	PAGE_COPY
465#define __P111	PAGE_COPY_X
466
467#define __S000	PAGE_NONE
468#define __S001	PAGE_READONLY_X
469#define __S010	PAGE_SHARED
470#define __S011	PAGE_SHARED_X
471#define __S100	PAGE_READONLY
472#define __S101	PAGE_READONLY_X
473#define __S110	PAGE_SHARED
474#define __S111	PAGE_SHARED_X
475
476#ifndef __ASSEMBLY__
477/* Make sure we get a link error if PMD_PAGE_SIZE is ever called on a
478 * kernel without large page PMD support */
479extern unsigned long bad_call_to_PMD_PAGE_SIZE(void);
480
481/*
482 * Conversions between PTE values and page frame numbers.
483 */
484
485/* in some case we want to additionaly adjust where the pfn is in the pte to
486 * allow room for more flags */
487#if defined(CONFIG_FSL_BOOKE) && defined(CONFIG_PTE_64BIT)
488#define PFN_SHIFT_OFFSET	(PAGE_SHIFT + 8)
489#else
490#define PFN_SHIFT_OFFSET	(PAGE_SHIFT)
491#endif
492
493#define pte_pfn(x)		(pte_val(x) >> PFN_SHIFT_OFFSET)
494#define pte_page(x)		pfn_to_page(pte_pfn(x))
495
496#define pfn_pte(pfn, prot)	__pte(((pte_basic_t)(pfn) << PFN_SHIFT_OFFSET) |\
497					pgprot_val(prot))
498#define mk_pte(page, prot)	pfn_pte(page_to_pfn(page), prot)
499
500/*
501 * ZERO_PAGE is a global shared page that is always zero: used
502 * for zero-mapped memory areas etc..
503 */
504extern unsigned long empty_zero_page[1024];
505#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
506
507#endif /* __ASSEMBLY__ */
508
509#define pte_none(pte)		((pte_val(pte) & ~_PTE_NONE_MASK) == 0)
510#define pte_present(pte)	(pte_val(pte) & _PAGE_PRESENT)
511#define pte_clear(mm,addr,ptep)	do { set_pte_at((mm), (addr), (ptep), __pte(0)); } while (0)
512
513#define pmd_none(pmd)		(!pmd_val(pmd))
514#define	pmd_bad(pmd)		(pmd_val(pmd) & _PMD_BAD)
515#define	pmd_present(pmd)	(pmd_val(pmd) & _PMD_PRESENT_MASK)
516#define	pmd_clear(pmdp)		do { pmd_val(*(pmdp)) = 0; } while (0)
517
518#ifndef __ASSEMBLY__
519/*
520 * The "pgd_xxx()" functions here are trivial for a folded two-level
521 * setup: the pgd is never bad, and a pmd always exists (as it's folded
522 * into the pgd entry)
523 */
524static inline int pgd_none(pgd_t pgd)		{ return 0; }
525static inline int pgd_bad(pgd_t pgd)		{ return 0; }
526static inline int pgd_present(pgd_t pgd)	{ return 1; }
527#define pgd_clear(xp)				do { } while (0)
528
529#define pgd_page_vaddr(pgd) \
530	((unsigned long) __va(pgd_val(pgd) & PAGE_MASK))
531
532/*
533 * The following only work if pte_present() is true.
534 * Undefined behaviour if not..
535 */
536static inline int pte_read(pte_t pte)		{ return pte_val(pte) & _PAGE_USER; }
537static inline int pte_write(pte_t pte)		{ return pte_val(pte) & _PAGE_RW; }
538static inline int pte_exec(pte_t pte)		{ return pte_val(pte) & _PAGE_EXEC; }
539static inline int pte_dirty(pte_t pte)		{ return pte_val(pte) & _PAGE_DIRTY; }
540static inline int pte_young(pte_t pte)		{ return pte_val(pte) & _PAGE_ACCESSED; }
541static inline int pte_file(pte_t pte)		{ return pte_val(pte) & _PAGE_FILE; }
542
543static inline void pte_uncache(pte_t pte)       { pte_val(pte) |= _PAGE_NO_CACHE; }
544static inline void pte_cache(pte_t pte)         { pte_val(pte) &= ~_PAGE_NO_CACHE; }
545
546static inline pte_t pte_rdprotect(pte_t pte) {
547	pte_val(pte) &= ~_PAGE_USER; return pte; }
548static inline pte_t pte_wrprotect(pte_t pte) {
549	pte_val(pte) &= ~(_PAGE_RW | _PAGE_HWWRITE); return pte; }
550static inline pte_t pte_exprotect(pte_t pte) {
551	pte_val(pte) &= ~_PAGE_EXEC; return pte; }
552static inline pte_t pte_mkclean(pte_t pte) {
553	pte_val(pte) &= ~(_PAGE_DIRTY | _PAGE_HWWRITE); return pte; }
554static inline pte_t pte_mkold(pte_t pte) {
555	pte_val(pte) &= ~_PAGE_ACCESSED; return pte; }
556
557static inline pte_t pte_mkread(pte_t pte) {
558	pte_val(pte) |= _PAGE_USER; return pte; }
559static inline pte_t pte_mkexec(pte_t pte) {
560	pte_val(pte) |= _PAGE_USER | _PAGE_EXEC; return pte; }
561static inline pte_t pte_mkwrite(pte_t pte) {
562	pte_val(pte) |= _PAGE_RW; return pte; }
563static inline pte_t pte_mkdirty(pte_t pte) {
564	pte_val(pte) |= _PAGE_DIRTY; return pte; }
565static inline pte_t pte_mkyoung(pte_t pte) {
566	pte_val(pte) |= _PAGE_ACCESSED; return pte; }
567
568static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
569{
570	pte_val(pte) = (pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot);
571	return pte;
572}
573
574/*
575 * When flushing the tlb entry for a page, we also need to flush the hash
576 * table entry.  flush_hash_pages is assembler (for speed) in hashtable.S.
577 */
578extern int flush_hash_pages(unsigned context, unsigned long va,
579			    unsigned long pmdval, int count);
580
581/* Add an HPTE to the hash table */
582extern void add_hash_page(unsigned context, unsigned long va,
583			  unsigned long pmdval);
584
585/*
586 * Atomic PTE updates.
587 *
588 * pte_update clears and sets bit atomically, and returns
589 * the old pte value.  In the 64-bit PTE case we lock around the
590 * low PTE word since we expect ALL flag bits to be there
591 */
592#ifndef CONFIG_PTE_64BIT
593static inline unsigned long pte_update(pte_t *p, unsigned long clr,
594				       unsigned long set)
595{
596	unsigned long old, tmp;
597
598	__asm__ __volatile__("\
5991:	lwarx	%0,0,%3\n\
600	andc	%1,%0,%4\n\
601	or	%1,%1,%5\n"
602	PPC405_ERR77(0,%3)
603"	stwcx.	%1,0,%3\n\
604	bne-	1b"
605	: "=&r" (old), "=&r" (tmp), "=m" (*p)
606	: "r" (p), "r" (clr), "r" (set), "m" (*p)
607	: "cc" );
608	return old;
609}
610#else
611static inline unsigned long long pte_update(pte_t *p, unsigned long clr,
612				       unsigned long set)
613{
614	unsigned long long old;
615	unsigned long tmp;
616
617	__asm__ __volatile__("\
6181:	lwarx	%L0,0,%4\n\
619	lwzx	%0,0,%3\n\
620	andc	%1,%L0,%5\n\
621	or	%1,%1,%6\n"
622	PPC405_ERR77(0,%3)
623"	stwcx.	%1,0,%4\n\
624	bne-	1b"
625	: "=&r" (old), "=&r" (tmp), "=m" (*p)
626	: "r" (p), "r" ((unsigned long)(p) + 4), "r" (clr), "r" (set), "m" (*p)
627	: "cc" );
628	return old;
629}
630#endif
631
632/*
633 * set_pte stores a linux PTE into the linux page table.
634 * On machines which use an MMU hash table we avoid changing the
635 * _PAGE_HASHPTE bit.
636 */
637static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
638			      pte_t *ptep, pte_t pte)
639{
640#if _PAGE_HASHPTE != 0
641	pte_update(ptep, ~_PAGE_HASHPTE, pte_val(pte) & ~_PAGE_HASHPTE);
642#else
643	*ptep = pte;
644#endif
645}
646
647/*
648 * 2.6 calles this without flushing the TLB entry, this is wrong
649 * for our hash-based implementation, we fix that up here
650 */
651#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
652static inline int __ptep_test_and_clear_young(unsigned int context, unsigned long addr, pte_t *ptep)
653{
654	unsigned long old;
655	old = pte_update(ptep, _PAGE_ACCESSED, 0);
656#if _PAGE_HASHPTE != 0
657	if (old & _PAGE_HASHPTE) {
658		unsigned long ptephys = __pa(ptep) & PAGE_MASK;
659		flush_hash_pages(context, addr, ptephys, 1);
660	}
661#endif
662	return (old & _PAGE_ACCESSED) != 0;
663}
664#define ptep_test_and_clear_young(__vma, __addr, __ptep) \
665	__ptep_test_and_clear_young((__vma)->vm_mm->context.id, __addr, __ptep)
666
667#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_DIRTY
668static inline int ptep_test_and_clear_dirty(struct vm_area_struct *vma,
669					    unsigned long addr, pte_t *ptep)
670{
671	return (pte_update(ptep, (_PAGE_DIRTY | _PAGE_HWWRITE), 0) & _PAGE_DIRTY) != 0;
672}
673
674#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
675static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
676				       pte_t *ptep)
677{
678	return __pte(pte_update(ptep, ~_PAGE_HASHPTE, 0));
679}
680
681#define __HAVE_ARCH_PTEP_SET_WRPROTECT
682static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr,
683				      pte_t *ptep)
684{
685	pte_update(ptep, (_PAGE_RW | _PAGE_HWWRITE), 0);
686}
687
688#define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
689static inline void __ptep_set_access_flags(pte_t *ptep, pte_t entry, int dirty)
690{
691	unsigned long bits = pte_val(entry) &
692		(_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW);
693	pte_update(ptep, 0, bits);
694}
695
696#define  ptep_set_access_flags(__vma, __address, __ptep, __entry, __dirty) \
697({									   \
698	int __changed = !pte_same(*(__ptep), __entry);			   \
699	if (__changed) {						   \
700		__ptep_set_access_flags(__ptep, __entry, __dirty);    	   \
701		flush_tlb_page_nohash(__vma, __address);		   \
702	}								   \
703	__changed;							   \
704})
705
706/*
707 * Macro to mark a page protection value as "uncacheable".
708 */
709#define pgprot_noncached(prot)	(__pgprot(pgprot_val(prot) | _PAGE_NO_CACHE | _PAGE_GUARDED))
710
711struct file;
712extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
713				     unsigned long size, pgprot_t vma_prot);
714#define __HAVE_PHYS_MEM_ACCESS_PROT
715
716#define __HAVE_ARCH_PTE_SAME
717#define pte_same(A,B)	(((pte_val(A) ^ pte_val(B)) & ~_PAGE_HASHPTE) == 0)
718
719/*
720 * Note that on Book E processors, the pmd contains the kernel virtual
721 * (lowmem) address of the pte page.  The physical address is less useful
722 * because everything runs with translation enabled (even the TLB miss
723 * handler).  On everything else the pmd contains the physical address
724 * of the pte page.  -- paulus
725 */
726#ifndef CONFIG_BOOKE
727#define pmd_page_vaddr(pmd)	\
728	((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
729#define pmd_page(pmd)		\
730	(mem_map + (pmd_val(pmd) >> PAGE_SHIFT))
731#else
732#define pmd_page_vaddr(pmd)	\
733	((unsigned long) (pmd_val(pmd) & PAGE_MASK))
734#define pmd_page(pmd)		\
735	(mem_map + (__pa(pmd_val(pmd)) >> PAGE_SHIFT))
736#endif
737
738/* to find an entry in a kernel page-table-directory */
739#define pgd_offset_k(address) pgd_offset(&init_mm, address)
740
741/* to find an entry in a page-table-directory */
742#define pgd_index(address)	 ((address) >> PGDIR_SHIFT)
743#define pgd_offset(mm, address)	 ((mm)->pgd + pgd_index(address))
744
745/* Find an entry in the second-level page table.. */
746static inline pmd_t * pmd_offset(pgd_t * dir, unsigned long address)
747{
748	return (pmd_t *) dir;
749}
750
751/* Find an entry in the third-level page table.. */
752#define pte_index(address)		\
753	(((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
754#define pte_offset_kernel(dir, addr)	\
755	((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(addr))
756#define pte_offset_map(dir, addr)		\
757	((pte_t *) kmap_atomic(pmd_page(*(dir)), KM_PTE0) + pte_index(addr))
758#define pte_offset_map_nested(dir, addr)	\
759	((pte_t *) kmap_atomic(pmd_page(*(dir)), KM_PTE1) + pte_index(addr))
760
761#define pte_unmap(pte)		kunmap_atomic(pte, KM_PTE0)
762#define pte_unmap_nested(pte)	kunmap_atomic(pte, KM_PTE1)
763
764extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
765
766extern void paging_init(void);
767
768/*
769 * Encode and decode a swap entry.
770 * Note that the bits we use in a PTE for representing a swap entry
771 * must not include the _PAGE_PRESENT bit, the _PAGE_FILE bit, or the
772 *_PAGE_HASHPTE bit (if used).  -- paulus
773 */
774#define __swp_type(entry)		((entry).val & 0x1f)
775#define __swp_offset(entry)		((entry).val >> 5)
776#define __swp_entry(type, offset)	((swp_entry_t) { (type) | ((offset) << 5) })
777#define __pte_to_swp_entry(pte)		((swp_entry_t) { pte_val(pte) >> 3 })
778#define __swp_entry_to_pte(x)		((pte_t) { (x).val << 3 })
779
780/* Encode and decode a nonlinear file mapping entry */
781#define PTE_FILE_MAX_BITS	29
782#define pte_to_pgoff(pte)	(pte_val(pte) >> 3)
783#define pgoff_to_pte(off)	((pte_t) { ((off) << 3) | _PAGE_FILE })
784
785/* CONFIG_APUS */
786/* For virtual address to physical address conversion */
787extern void cache_clear(__u32 addr, int length);
788extern void cache_push(__u32 addr, int length);
789extern int mm_end_of_chunk (unsigned long addr, int len);
790extern unsigned long iopa(unsigned long addr);
791extern unsigned long mm_ptov(unsigned long addr) __attribute_const__;
792
793/* Values for nocacheflag and cmode */
794/* These are not used by the APUS kernel_map, but prevents
795   compilation errors. */
796#define	KERNELMAP_FULL_CACHING		0
797#define	KERNELMAP_NOCACHE_SER		1
798#define	KERNELMAP_NOCACHE_NONSER	2
799#define	KERNELMAP_NO_COPYBACK		3
800
801/*
802 * Map some physical address range into the kernel address space.
803 */
804extern unsigned long kernel_map(unsigned long paddr, unsigned long size,
805				int nocacheflag, unsigned long *memavailp );
806
807/*
808 * Set cache mode of (kernel space) address range.
809 */
810extern void kernel_set_cachemode (unsigned long address, unsigned long size,
811                                 unsigned int cmode);
812
813/* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
814#define kern_addr_valid(addr)	(1)
815
816#ifdef CONFIG_PHYS_64BIT
817extern int remap_pfn_range(struct vm_area_struct *vma, unsigned long from,
818			unsigned long paddr, unsigned long size, pgprot_t prot);
819
820static inline int io_remap_pfn_range(struct vm_area_struct *vma,
821					unsigned long vaddr,
822					unsigned long pfn,
823					unsigned long size,
824					pgprot_t prot)
825{
826	phys_addr_t paddr64 = fixup_bigphys_addr(pfn << PAGE_SHIFT, size);
827	return remap_pfn_range(vma, vaddr, paddr64 >> PAGE_SHIFT, size, prot);
828}
829#else
830#define io_remap_pfn_range(vma, vaddr, pfn, size, prot)		\
831		remap_pfn_range(vma, vaddr, pfn, size, prot)
832#endif
833
834/*
835 * No page table caches to initialise
836 */
837#define pgtable_cache_init()	do { } while (0)
838
839extern int get_pteptr(struct mm_struct *mm, unsigned long addr, pte_t **ptep,
840		      pmd_t **pmdp);
841
842#include <asm-generic/pgtable.h>
843
844#endif /* !__ASSEMBLY__ */
845
846#endif /* _PPC_PGTABLE_H */
847#endif /* __KERNEL__ */
848