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