1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
4  * Copyright (C) 2008-2009 PetaLogix
5  * Copyright (C) 2006 Atmark Techno, Inc.
6  */
7 
8 #ifndef _ASM_MICROBLAZE_PGTABLE_H
9 #define _ASM_MICROBLAZE_PGTABLE_H
10 
11 #include <asm/setup.h>
12 
13 #ifndef __ASSEMBLY__
14 extern int mem_init_done;
15 #endif
16 
17 #ifndef CONFIG_MMU
18 
19 #define pgd_present(pgd)	(1) /* pages are always present on non MMU */
20 #define pgd_none(pgd)		(0)
21 #define pgd_bad(pgd)		(0)
22 #define pgd_clear(pgdp)
23 #define kern_addr_valid(addr)	(1)
24 #define	pmd_offset(a, b)	((void *) 0)
25 
26 #define PAGE_NONE		__pgprot(0) /* these mean nothing to non MMU */
27 #define PAGE_SHARED		__pgprot(0) /* these mean nothing to non MMU */
28 #define PAGE_COPY		__pgprot(0) /* these mean nothing to non MMU */
29 #define PAGE_READONLY		__pgprot(0) /* these mean nothing to non MMU */
30 #define PAGE_KERNEL		__pgprot(0) /* these mean nothing to non MMU */
31 
32 #define pgprot_noncached(x)	(x)
33 #define pgprot_writecombine	pgprot_noncached
34 #define pgprot_device		pgprot_noncached
35 
36 #define __swp_type(x)		(0)
37 #define __swp_offset(x)		(0)
38 #define __swp_entry(typ, off)	((swp_entry_t) { ((typ) | ((off) << 7)) })
39 #define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })
40 #define __swp_entry_to_pte(x)	((pte_t) { (x).val })
41 
42 #define ZERO_PAGE(vaddr)	({ BUG(); NULL; })
43 
44 #define swapper_pg_dir ((pgd_t *) NULL)
45 
46 #define arch_enter_lazy_cpu_mode()	do {} while (0)
47 
48 #define pgprot_noncached_wc(prot)	prot
49 
50 /*
51  * All 32bit addresses are effectively valid for vmalloc...
52  * Sort of meaningless for non-VM targets.
53  */
54 #define	VMALLOC_START	0
55 #define	VMALLOC_END	0xffffffff
56 
57 #else /* CONFIG_MMU */
58 
59 #include <asm-generic/pgtable-nopmd.h>
60 
61 #ifdef __KERNEL__
62 #ifndef __ASSEMBLY__
63 
64 #include <linux/sched.h>
65 #include <linux/threads.h>
66 #include <asm/processor.h>		/* For TASK_SIZE */
67 #include <asm/mmu.h>
68 #include <asm/page.h>
69 
70 #define FIRST_USER_ADDRESS	0UL
71 
72 extern unsigned long va_to_phys(unsigned long address);
73 extern pte_t *va_to_pte(unsigned long address);
74 
75 /*
76  * The following only work if pte_present() is true.
77  * Undefined behaviour if not..
78  */
79 
80 /* Start and end of the vmalloc area. */
81 /* Make sure to map the vmalloc area above the pinned kernel memory area
82    of 32Mb.  */
83 #define VMALLOC_START	(CONFIG_KERNEL_START + CONFIG_LOWMEM_SIZE)
84 #define VMALLOC_END	ioremap_bot
85 
86 #endif /* __ASSEMBLY__ */
87 
88 /*
89  * Macro to mark a page protection value as "uncacheable".
90  */
91 
92 #define _PAGE_CACHE_CTL	(_PAGE_GUARDED | _PAGE_NO_CACHE | \
93 							_PAGE_WRITETHRU)
94 
95 #define pgprot_noncached(prot) \
96 			(__pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) | \
97 					_PAGE_NO_CACHE | _PAGE_GUARDED))
98 
99 #define pgprot_noncached_wc(prot) \
100 			 (__pgprot((pgprot_val(prot) & ~_PAGE_CACHE_CTL) | \
101 							_PAGE_NO_CACHE))
102 
103 /*
104  * The MicroBlaze MMU is identical to the PPC-40x MMU, and uses a hash
105  * table containing PTEs, together with a set of 16 segment registers, to
106  * define the virtual to physical address mapping.
107  *
108  * We use the hash table as an extended TLB, i.e. a cache of currently
109  * active mappings.  We maintain a two-level page table tree, much
110  * like that used by the i386, for the sake of the Linux memory
111  * management code.  Low-level assembler code in hashtable.S
112  * (procedure hash_page) is responsible for extracting ptes from the
113  * tree and putting them into the hash table when necessary, and
114  * updating the accessed and modified bits in the page table tree.
115  */
116 
117 /*
118  * The MicroBlaze processor has a TLB architecture identical to PPC-40x. The
119  * instruction and data sides share a unified, 64-entry, semi-associative
120  * TLB which is maintained totally under software control. In addition, the
121  * instruction side has a hardware-managed, 2,4, or 8-entry, fully-associative
122  * TLB which serves as a first level to the shared TLB. These two TLBs are
123  * known as the UTLB and ITLB, respectively (see "mmu.h" for definitions).
124  */
125 
126 /*
127  * The normal case is that PTEs are 32-bits and we have a 1-page
128  * 1024-entry pgdir pointing to 1-page 1024-entry PTE pages.  -- paulus
129  *
130  */
131 
132 /* PGDIR_SHIFT determines what a top-level page table entry can map */
133 #define PGDIR_SHIFT	(PAGE_SHIFT + PTE_SHIFT)
134 #define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
135 #define PGDIR_MASK	(~(PGDIR_SIZE-1))
136 
137 /*
138  * entries per page directory level: our page-table tree is two-level, so
139  * we don't really have any PMD directory.
140  */
141 #define PTRS_PER_PTE	(1 << PTE_SHIFT)
142 #define PTRS_PER_PMD	1
143 #define PTRS_PER_PGD	(1 << (32 - PGDIR_SHIFT))
144 
145 #define USER_PTRS_PER_PGD	(TASK_SIZE / PGDIR_SIZE)
146 #define FIRST_USER_PGD_NR	0
147 
148 #define USER_PGD_PTRS (PAGE_OFFSET >> PGDIR_SHIFT)
149 #define KERNEL_PGD_PTRS (PTRS_PER_PGD-USER_PGD_PTRS)
150 
151 #define pte_ERROR(e) \
152 	printk(KERN_ERR "%s:%d: bad pte "PTE_FMT".\n", \
153 		__FILE__, __LINE__, pte_val(e))
154 #define pgd_ERROR(e) \
155 	printk(KERN_ERR "%s:%d: bad pgd %08lx.\n", \
156 		__FILE__, __LINE__, pgd_val(e))
157 
158 /*
159  * Bits in a linux-style PTE.  These match the bits in the
160  * (hardware-defined) PTE as closely as possible.
161  */
162 
163 /* There are several potential gotchas here.  The hardware TLBLO
164  * field looks like this:
165  *
166  * 0  1  2  3  4  ... 18 19 20 21 22 23 24 25 26 27 28 29 30 31
167  * RPN.....................  0  0 EX WR ZSEL.......  W  I  M  G
168  *
169  * Where possible we make the Linux PTE bits match up with this
170  *
171  * - bits 20 and 21 must be cleared, because we use 4k pages (4xx can
172  * support down to 1k pages), this is done in the TLBMiss exception
173  * handler.
174  * - We use only zones 0 (for kernel pages) and 1 (for user pages)
175  * of the 16 available.  Bit 24-26 of the TLB are cleared in the TLB
176  * miss handler.  Bit 27 is PAGE_USER, thus selecting the correct
177  * zone.
178  * - PRESENT *must* be in the bottom two bits because swap cache
179  * entries use the top 30 bits.  Because 4xx doesn't support SMP
180  * anyway, M is irrelevant so we borrow it for PAGE_PRESENT.  Bit 30
181  * is cleared in the TLB miss handler before the TLB entry is loaded.
182  * - All other bits of the PTE are loaded into TLBLO without
183  *  * modification, leaving us only the bits 20, 21, 24, 25, 26, 30 for
184  * software PTE bits.  We actually use bits 21, 24, 25, and
185  * 30 respectively for the software bits: ACCESSED, DIRTY, RW, and
186  * PRESENT.
187  */
188 
189 /* Definitions for MicroBlaze. */
190 #define	_PAGE_GUARDED	0x001	/* G: page is guarded from prefetch */
191 #define _PAGE_PRESENT	0x002	/* software: PTE contains a translation */
192 #define	_PAGE_NO_CACHE	0x004	/* I: caching is inhibited */
193 #define	_PAGE_WRITETHRU	0x008	/* W: caching is write-through */
194 #define	_PAGE_USER	0x010	/* matches one of the zone permission bits */
195 #define	_PAGE_RW	0x040	/* software: Writes permitted */
196 #define	_PAGE_DIRTY	0x080	/* software: dirty page */
197 #define _PAGE_HWWRITE	0x100	/* hardware: Dirty & RW, set in exception */
198 #define _PAGE_HWEXEC	0x200	/* hardware: EX permission */
199 #define _PAGE_ACCESSED	0x400	/* software: R: page referenced */
200 #define _PMD_PRESENT	PAGE_MASK
201 
202 /*
203  * Some bits are unused...
204  */
205 #ifndef _PAGE_HASHPTE
206 #define _PAGE_HASHPTE	0
207 #endif
208 #ifndef _PTE_NONE_MASK
209 #define _PTE_NONE_MASK	0
210 #endif
211 #ifndef _PAGE_SHARED
212 #define _PAGE_SHARED	0
213 #endif
214 #ifndef _PAGE_EXEC
215 #define _PAGE_EXEC	0
216 #endif
217 
218 #define _PAGE_CHG_MASK	(PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
219 
220 /*
221  * Note: the _PAGE_COHERENT bit automatically gets set in the hardware
222  * PTE if CONFIG_SMP is defined (hash_page does this); there is no need
223  * to have it in the Linux PTE, and in fact the bit could be reused for
224  * another purpose.  -- paulus.
225  */
226 #define _PAGE_BASE	(_PAGE_PRESENT | _PAGE_ACCESSED)
227 #define _PAGE_WRENABLE	(_PAGE_RW | _PAGE_DIRTY | _PAGE_HWWRITE)
228 
229 #define _PAGE_KERNEL \
230 	(_PAGE_BASE | _PAGE_WRENABLE | _PAGE_SHARED | _PAGE_HWEXEC)
231 
232 #define _PAGE_IO	(_PAGE_KERNEL | _PAGE_NO_CACHE | _PAGE_GUARDED)
233 
234 #define PAGE_NONE	__pgprot(_PAGE_BASE)
235 #define PAGE_READONLY	__pgprot(_PAGE_BASE | _PAGE_USER)
236 #define PAGE_READONLY_X	__pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC)
237 #define PAGE_SHARED	__pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW)
238 #define PAGE_SHARED_X \
239 		__pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_RW | _PAGE_EXEC)
240 #define PAGE_COPY	__pgprot(_PAGE_BASE | _PAGE_USER)
241 #define PAGE_COPY_X	__pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC)
242 
243 #define PAGE_KERNEL	__pgprot(_PAGE_KERNEL)
244 #define PAGE_KERNEL_RO	__pgprot(_PAGE_BASE | _PAGE_SHARED)
245 #define PAGE_KERNEL_CI	__pgprot(_PAGE_IO)
246 
247 /*
248  * We consider execute permission the same as read.
249  * Also, write permissions imply read permissions.
250  */
251 #define __P000	PAGE_NONE
252 #define __P001	PAGE_READONLY_X
253 #define __P010	PAGE_COPY
254 #define __P011	PAGE_COPY_X
255 #define __P100	PAGE_READONLY
256 #define __P101	PAGE_READONLY_X
257 #define __P110	PAGE_COPY
258 #define __P111	PAGE_COPY_X
259 
260 #define __S000	PAGE_NONE
261 #define __S001	PAGE_READONLY_X
262 #define __S010	PAGE_SHARED
263 #define __S011	PAGE_SHARED_X
264 #define __S100	PAGE_READONLY
265 #define __S101	PAGE_READONLY_X
266 #define __S110	PAGE_SHARED
267 #define __S111	PAGE_SHARED_X
268 
269 #ifndef __ASSEMBLY__
270 /*
271  * ZERO_PAGE is a global shared page that is always zero: used
272  * for zero-mapped memory areas etc..
273  */
274 extern unsigned long empty_zero_page[1024];
275 #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
276 
277 #endif /* __ASSEMBLY__ */
278 
279 #define pte_none(pte)		((pte_val(pte) & ~_PTE_NONE_MASK) == 0)
280 #define pte_present(pte)	(pte_val(pte) & _PAGE_PRESENT)
281 #define pte_clear(mm, addr, ptep) \
282 	do { set_pte_at((mm), (addr), (ptep), __pte(0)); } while (0)
283 
284 #define pmd_none(pmd)		(!pmd_val(pmd))
285 #define	pmd_bad(pmd)		((pmd_val(pmd) & _PMD_PRESENT) == 0)
286 #define	pmd_present(pmd)	((pmd_val(pmd) & _PMD_PRESENT) != 0)
287 #define	pmd_clear(pmdp)		do { pmd_val(*(pmdp)) = 0; } while (0)
288 
289 #define pte_page(x)		(mem_map + (unsigned long) \
290 				((pte_val(x) - memory_start) >> PAGE_SHIFT))
291 #define PFN_SHIFT_OFFSET	(PAGE_SHIFT)
292 
293 #define pte_pfn(x)		(pte_val(x) >> PFN_SHIFT_OFFSET)
294 
295 #define pfn_pte(pfn, prot) \
296 	__pte(((pte_basic_t)(pfn) << PFN_SHIFT_OFFSET) | pgprot_val(prot))
297 
298 #ifndef __ASSEMBLY__
299 /*
300  * The following only work if pte_present() is true.
301  * Undefined behaviour if not..
302  */
303 static inline int pte_read(pte_t pte)  { return pte_val(pte) & _PAGE_USER; }
304 static inline int pte_write(pte_t pte) { return pte_val(pte) & _PAGE_RW; }
305 static inline int pte_exec(pte_t pte)  { return pte_val(pte) & _PAGE_EXEC; }
306 static inline int pte_dirty(pte_t pte) { return pte_val(pte) & _PAGE_DIRTY; }
307 static inline int pte_young(pte_t pte) { return pte_val(pte) & _PAGE_ACCESSED; }
308 
309 static inline void pte_uncache(pte_t pte) { pte_val(pte) |= _PAGE_NO_CACHE; }
310 static inline void pte_cache(pte_t pte)   { pte_val(pte) &= ~_PAGE_NO_CACHE; }
311 
312 static inline pte_t pte_rdprotect(pte_t pte) \
313 		{ pte_val(pte) &= ~_PAGE_USER; return pte; }
314 static inline pte_t pte_wrprotect(pte_t pte) \
315 	{ pte_val(pte) &= ~(_PAGE_RW | _PAGE_HWWRITE); return pte; }
316 static inline pte_t pte_exprotect(pte_t pte) \
317 	{ pte_val(pte) &= ~_PAGE_EXEC; return pte; }
318 static inline pte_t pte_mkclean(pte_t pte) \
319 	{ pte_val(pte) &= ~(_PAGE_DIRTY | _PAGE_HWWRITE); return pte; }
320 static inline pte_t pte_mkold(pte_t pte) \
321 	{ pte_val(pte) &= ~_PAGE_ACCESSED; return pte; }
322 
323 static inline pte_t pte_mkread(pte_t pte) \
324 	{ pte_val(pte) |= _PAGE_USER; return pte; }
325 static inline pte_t pte_mkexec(pte_t pte) \
326 	{ pte_val(pte) |= _PAGE_USER | _PAGE_EXEC; return pte; }
327 static inline pte_t pte_mkwrite(pte_t pte) \
328 	{ pte_val(pte) |= _PAGE_RW; return pte; }
329 static inline pte_t pte_mkdirty(pte_t pte) \
330 	{ pte_val(pte) |= _PAGE_DIRTY; return pte; }
331 static inline pte_t pte_mkyoung(pte_t pte) \
332 	{ pte_val(pte) |= _PAGE_ACCESSED; return pte; }
333 
334 /*
335  * Conversion functions: convert a page and protection to a page entry,
336  * and a page entry and page directory to the page they refer to.
337  */
338 
339 static inline pte_t mk_pte_phys(phys_addr_t physpage, pgprot_t pgprot)
340 {
341 	pte_t pte;
342 	pte_val(pte) = physpage | pgprot_val(pgprot);
343 	return pte;
344 }
345 
346 #define mk_pte(page, pgprot) \
347 ({									   \
348 	pte_t pte;							   \
349 	pte_val(pte) = (((page - mem_map) << PAGE_SHIFT) + memory_start) |  \
350 			pgprot_val(pgprot);				   \
351 	pte;								   \
352 })
353 
354 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
355 {
356 	pte_val(pte) = (pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot);
357 	return pte;
358 }
359 
360 /*
361  * Atomic PTE updates.
362  *
363  * pte_update clears and sets bit atomically, and returns
364  * the old pte value.
365  * The ((unsigned long)(p+1) - 4) hack is to get to the least-significant
366  * 32 bits of the PTE regardless of whether PTEs are 32 or 64 bits.
367  */
368 static inline unsigned long pte_update(pte_t *p, unsigned long clr,
369 				unsigned long set)
370 {
371 	unsigned long flags, old, tmp;
372 
373 	raw_local_irq_save(flags);
374 
375 	__asm__ __volatile__(	"lw	%0, %2, r0	\n"
376 				"andn	%1, %0, %3	\n"
377 				"or	%1, %1, %4	\n"
378 				"sw	%1, %2, r0	\n"
379 			: "=&r" (old), "=&r" (tmp)
380 			: "r" ((unsigned long)(p + 1) - 4), "r" (clr), "r" (set)
381 			: "cc");
382 
383 	raw_local_irq_restore(flags);
384 
385 	return old;
386 }
387 
388 /*
389  * set_pte stores a linux PTE into the linux page table.
390  */
391 static inline void set_pte(struct mm_struct *mm, unsigned long addr,
392 		pte_t *ptep, pte_t pte)
393 {
394 	*ptep = pte;
395 }
396 
397 static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
398 		pte_t *ptep, pte_t pte)
399 {
400 	*ptep = pte;
401 }
402 
403 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
404 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
405 		unsigned long address, pte_t *ptep)
406 {
407 	return (pte_update(ptep, _PAGE_ACCESSED, 0) & _PAGE_ACCESSED) != 0;
408 }
409 
410 static inline int ptep_test_and_clear_dirty(struct mm_struct *mm,
411 		unsigned long addr, pte_t *ptep)
412 {
413 	return (pte_update(ptep, \
414 		(_PAGE_DIRTY | _PAGE_HWWRITE), 0) & _PAGE_DIRTY) != 0;
415 }
416 
417 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
418 static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
419 		unsigned long addr, pte_t *ptep)
420 {
421 	return __pte(pte_update(ptep, ~_PAGE_HASHPTE, 0));
422 }
423 
424 /*static inline void ptep_set_wrprotect(struct mm_struct *mm,
425 		unsigned long addr, pte_t *ptep)
426 {
427 	pte_update(ptep, (_PAGE_RW | _PAGE_HWWRITE), 0);
428 }*/
429 
430 static inline void ptep_mkdirty(struct mm_struct *mm,
431 		unsigned long addr, pte_t *ptep)
432 {
433 	pte_update(ptep, 0, _PAGE_DIRTY);
434 }
435 
436 /*#define pte_same(A,B)	(((pte_val(A) ^ pte_val(B)) & ~_PAGE_HASHPTE) == 0)*/
437 
438 /* Convert pmd entry to page */
439 /* our pmd entry is an effective address of pte table*/
440 /* returns effective address of the pmd entry*/
441 #define pmd_page_kernel(pmd)	((unsigned long) (pmd_val(pmd) & PAGE_MASK))
442 
443 /* returns struct *page of the pmd entry*/
444 #define pmd_page(pmd)	(pfn_to_page(__pa(pmd_val(pmd)) >> PAGE_SHIFT))
445 
446 /* to find an entry in a kernel page-table-directory */
447 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
448 
449 /* to find an entry in a page-table-directory */
450 #define pgd_index(address)	 ((address) >> PGDIR_SHIFT)
451 #define pgd_offset(mm, address)	 ((mm)->pgd + pgd_index(address))
452 
453 /* Find an entry in the third-level page table.. */
454 #define pte_index(address)		\
455 	(((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
456 #define pte_offset_kernel(dir, addr)	\
457 	((pte_t *) pmd_page_kernel(*(dir)) + pte_index(addr))
458 #define pte_offset_map(dir, addr)		\
459 	((pte_t *) kmap_atomic(pmd_page(*(dir))) + pte_index(addr))
460 
461 #define pte_unmap(pte)		kunmap_atomic(pte)
462 
463 extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
464 
465 /*
466  * Encode and decode a swap entry.
467  * Note that the bits we use in a PTE for representing a swap entry
468  * must not include the _PAGE_PRESENT bit, or the _PAGE_HASHPTE bit
469  * (if used).  -- paulus
470  */
471 #define __swp_type(entry)		((entry).val & 0x3f)
472 #define __swp_offset(entry)	((entry).val >> 6)
473 #define __swp_entry(type, offset) \
474 		((swp_entry_t) { (type) | ((offset) << 6) })
475 #define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) >> 2 })
476 #define __swp_entry_to_pte(x)	((pte_t) { (x).val << 2 })
477 
478 extern unsigned long iopa(unsigned long addr);
479 
480 /* Values for nocacheflag and cmode */
481 /* These are not used by the APUS kernel_map, but prevents
482  * compilation errors.
483  */
484 #define	IOMAP_FULL_CACHING	0
485 #define	IOMAP_NOCACHE_SER	1
486 #define	IOMAP_NOCACHE_NONSER	2
487 #define	IOMAP_NO_COPYBACK	3
488 
489 /* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
490 #define kern_addr_valid(addr)	(1)
491 
492 void do_page_fault(struct pt_regs *regs, unsigned long address,
493 		   unsigned long error_code);
494 
495 void mapin_ram(void);
496 int map_page(unsigned long va, phys_addr_t pa, int flags);
497 
498 extern int mem_init_done;
499 
500 asmlinkage void __init mmu_init(void);
501 
502 void __init *early_get_page(void);
503 
504 #endif /* __ASSEMBLY__ */
505 #endif /* __KERNEL__ */
506 
507 #endif /* CONFIG_MMU */
508 
509 #ifndef __ASSEMBLY__
510 #include <asm-generic/pgtable.h>
511 
512 extern unsigned long ioremap_bot, ioremap_base;
513 
514 void setup_memory(void);
515 #endif /* __ASSEMBLY__ */
516 
517 #endif /* _ASM_MICROBLAZE_PGTABLE_H */
518