1#ifndef _ASM_M32R_PGTABLE_H
2#define _ASM_M32R_PGTABLE_H
3
4#include <asm-generic/4level-fixup.h>
5
6#ifdef __KERNEL__
7/*
8 * The Linux memory management assumes a three-level page table setup. On
9 * the M32R, we use that, but "fold" the mid level into the top-level page
10 * table, so that we physically have the same two-level page table as the
11 * M32R mmu expects.
12 *
13 * This file contains the functions and defines necessary to modify and use
14 * the M32R page table tree.
15 */
16
17/* CAUTION!: If you change macro definitions in this file, you might have to
18 * change arch/m32r/mmu.S manually.
19 */
20
21#ifndef __ASSEMBLY__
22
23#include <linux/threads.h>
24#include <linux/bitops.h>
25#include <asm/processor.h>
26#include <asm/addrspace.h>
27#include <asm/page.h>
28
29struct mm_struct;
30struct vm_area_struct;
31
32extern pgd_t swapper_pg_dir[1024];
33extern void paging_init(void);
34
35/*
36 * ZERO_PAGE is a global shared page that is always zero: used
37 * for zero-mapped memory areas etc..
38 */
39extern unsigned long empty_zero_page[1024];
40#define ZERO_PAGE(vaddr)	(virt_to_page(empty_zero_page))
41
42#endif /* !__ASSEMBLY__ */
43
44#ifndef __ASSEMBLY__
45#include <asm/pgtable-2level.h>
46#endif
47
48#define pgtable_cache_init()	do { } while (0)
49
50#define PMD_SIZE	(1UL << PMD_SHIFT)
51#define PMD_MASK	(~(PMD_SIZE - 1))
52#define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
53#define PGDIR_MASK	(~(PGDIR_SIZE - 1))
54
55#define USER_PTRS_PER_PGD	(TASK_SIZE / PGDIR_SIZE)
56#define FIRST_USER_ADDRESS	0UL
57
58#ifndef __ASSEMBLY__
59/* Just any arbitrary offset to the start of the vmalloc VM area: the
60 * current 8MB value just means that there will be a 8MB "hole" after the
61 * physical memory until the kernel virtual memory starts.  That means that
62 * any out-of-bounds memory accesses will hopefully be caught.
63 * The vmalloc() routines leaves a hole of 4kB between each vmalloced
64 * area for the same reason. ;)
65 */
66#define VMALLOC_START		KSEG2
67#define VMALLOC_END		KSEG3
68
69/*
70 *     M32R TLB format
71 *
72 *     [0]    [1:19]           [20:23]       [24:31]
73 *     +-----------------------+----+-------------+
74 *     |          VPN          |0000|    ASID     |
75 *     +-----------------------+----+-------------+
76 *     +-+---------------------+----+-+---+-+-+-+-+
77 *     |0         PPN          |0000|N|AC |L|G|V| |
78 *     +-+---------------------+----+-+---+-+-+-+-+
79 *                                     RWX
80 */
81
82#define _PAGE_BIT_DIRTY		0	/* software: page changed */
83#define _PAGE_BIT_PRESENT	1	/* Valid: page is valid */
84#define _PAGE_BIT_GLOBAL	2	/* Global */
85#define _PAGE_BIT_LARGE		3	/* Large */
86#define _PAGE_BIT_EXEC		4	/* Execute */
87#define _PAGE_BIT_WRITE		5	/* Write */
88#define _PAGE_BIT_READ		6	/* Read */
89#define _PAGE_BIT_NONCACHABLE	7	/* Non cachable */
90#define _PAGE_BIT_ACCESSED	8	/* software: page referenced */
91#define _PAGE_BIT_PROTNONE	9	/* software: if not present */
92
93#define _PAGE_DIRTY		(1UL << _PAGE_BIT_DIRTY)
94#define _PAGE_PRESENT		(1UL << _PAGE_BIT_PRESENT)
95#define _PAGE_GLOBAL		(1UL << _PAGE_BIT_GLOBAL)
96#define _PAGE_LARGE		(1UL << _PAGE_BIT_LARGE)
97#define _PAGE_EXEC		(1UL << _PAGE_BIT_EXEC)
98#define _PAGE_WRITE		(1UL << _PAGE_BIT_WRITE)
99#define _PAGE_READ		(1UL << _PAGE_BIT_READ)
100#define _PAGE_NONCACHABLE	(1UL << _PAGE_BIT_NONCACHABLE)
101#define _PAGE_ACCESSED		(1UL << _PAGE_BIT_ACCESSED)
102#define _PAGE_PROTNONE		(1UL << _PAGE_BIT_PROTNONE)
103
104#define _PAGE_TABLE	\
105	( _PAGE_PRESENT | _PAGE_WRITE | _PAGE_READ | _PAGE_ACCESSED \
106	| _PAGE_DIRTY )
107#define _KERNPG_TABLE	\
108	( _PAGE_PRESENT | _PAGE_WRITE | _PAGE_READ | _PAGE_ACCESSED \
109	| _PAGE_DIRTY )
110#define _PAGE_CHG_MASK	\
111	( PTE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY )
112
113#ifdef CONFIG_MMU
114#define PAGE_NONE	\
115	__pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED)
116#define PAGE_SHARED	\
117	__pgprot(_PAGE_PRESENT | _PAGE_WRITE | _PAGE_READ | _PAGE_ACCESSED)
118#define PAGE_SHARED_EXEC \
119	__pgprot(_PAGE_PRESENT | _PAGE_EXEC | _PAGE_WRITE | _PAGE_READ \
120		| _PAGE_ACCESSED)
121#define PAGE_COPY	\
122	__pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_ACCESSED)
123#define PAGE_COPY_EXEC	\
124	__pgprot(_PAGE_PRESENT | _PAGE_EXEC | _PAGE_READ | _PAGE_ACCESSED)
125#define PAGE_READONLY	\
126	__pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_ACCESSED)
127#define PAGE_READONLY_EXEC \
128	__pgprot(_PAGE_PRESENT | _PAGE_EXEC | _PAGE_READ | _PAGE_ACCESSED)
129
130#define __PAGE_KERNEL	\
131	( _PAGE_PRESENT | _PAGE_EXEC | _PAGE_WRITE | _PAGE_READ | _PAGE_DIRTY \
132	| _PAGE_ACCESSED )
133#define __PAGE_KERNEL_RO	( __PAGE_KERNEL & ~_PAGE_WRITE )
134#define __PAGE_KERNEL_NOCACHE	( __PAGE_KERNEL | _PAGE_NONCACHABLE)
135
136#define MAKE_GLOBAL(x)	__pgprot((x) | _PAGE_GLOBAL)
137
138#define PAGE_KERNEL		MAKE_GLOBAL(__PAGE_KERNEL)
139#define PAGE_KERNEL_RO		MAKE_GLOBAL(__PAGE_KERNEL_RO)
140#define PAGE_KERNEL_NOCACHE	MAKE_GLOBAL(__PAGE_KERNEL_NOCACHE)
141
142#else
143#define PAGE_NONE		__pgprot(0)
144#define PAGE_SHARED		__pgprot(0)
145#define PAGE_SHARED_EXEC	__pgprot(0)
146#define PAGE_COPY		__pgprot(0)
147#define PAGE_COPY_EXEC		__pgprot(0)
148#define PAGE_READONLY		__pgprot(0)
149#define PAGE_READONLY_EXEC	__pgprot(0)
150
151#define PAGE_KERNEL		__pgprot(0)
152#define PAGE_KERNEL_RO		__pgprot(0)
153#define PAGE_KERNEL_NOCACHE	__pgprot(0)
154#endif /* CONFIG_MMU */
155
156	/* xwr */
157#define __P000	PAGE_NONE
158#define __P001	PAGE_READONLY
159#define __P010	PAGE_COPY
160#define __P011	PAGE_COPY
161#define __P100	PAGE_READONLY_EXEC
162#define __P101	PAGE_READONLY_EXEC
163#define __P110	PAGE_COPY_EXEC
164#define __P111	PAGE_COPY_EXEC
165
166#define __S000	PAGE_NONE
167#define __S001	PAGE_READONLY
168#define __S010	PAGE_SHARED
169#define __S011	PAGE_SHARED
170#define __S100	PAGE_READONLY_EXEC
171#define __S101	PAGE_READONLY_EXEC
172#define __S110	PAGE_SHARED_EXEC
173#define __S111	PAGE_SHARED_EXEC
174
175/* page table for 0-4MB for everybody */
176
177#define pte_present(x)	(pte_val(x) & (_PAGE_PRESENT | _PAGE_PROTNONE))
178#define pte_clear(mm,addr,xp)	do { set_pte_at(mm, addr, xp, __pte(0)); } while (0)
179
180#define pmd_none(x)	(!pmd_val(x))
181#define pmd_present(x)	(pmd_val(x) & _PAGE_PRESENT)
182#define pmd_clear(xp)	do { set_pmd(xp, __pmd(0)); } while (0)
183#define	pmd_bad(x)	((pmd_val(x) & ~PAGE_MASK) != _KERNPG_TABLE)
184
185#define pages_to_mb(x)	((x) >> (20 - PAGE_SHIFT))
186
187/*
188 * The following only work if pte_present() is true.
189 * Undefined behaviour if not..
190 */
191static inline int pte_dirty(pte_t pte)
192{
193	return pte_val(pte) & _PAGE_DIRTY;
194}
195
196static inline int pte_young(pte_t pte)
197{
198	return pte_val(pte) & _PAGE_ACCESSED;
199}
200
201static inline int pte_write(pte_t pte)
202{
203	return pte_val(pte) & _PAGE_WRITE;
204}
205
206static inline int pte_special(pte_t pte)
207{
208	return 0;
209}
210
211static inline pte_t pte_mkclean(pte_t pte)
212{
213	pte_val(pte) &= ~_PAGE_DIRTY;
214	return pte;
215}
216
217static inline pte_t pte_mkold(pte_t pte)
218{
219	pte_val(pte) &= ~_PAGE_ACCESSED;
220	return pte;
221}
222
223static inline pte_t pte_wrprotect(pte_t pte)
224{
225	pte_val(pte) &= ~_PAGE_WRITE;
226	return pte;
227}
228
229static inline pte_t pte_mkdirty(pte_t pte)
230{
231	pte_val(pte) |= _PAGE_DIRTY;
232	return pte;
233}
234
235static inline pte_t pte_mkyoung(pte_t pte)
236{
237	pte_val(pte) |= _PAGE_ACCESSED;
238	return pte;
239}
240
241static inline pte_t pte_mkwrite(pte_t pte)
242{
243	pte_val(pte) |= _PAGE_WRITE;
244	return pte;
245}
246
247static inline pte_t pte_mkspecial(pte_t pte)
248{
249	return pte;
250}
251
252static inline  int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
253{
254	return test_and_clear_bit(_PAGE_BIT_ACCESSED, ptep);
255}
256
257static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
258{
259	clear_bit(_PAGE_BIT_WRITE, ptep);
260}
261
262/*
263 * Macro and implementation to make a page protection as uncachable.
264 */
265static inline pgprot_t pgprot_noncached(pgprot_t _prot)
266{
267	unsigned long prot = pgprot_val(_prot);
268
269	prot |= _PAGE_NONCACHABLE;
270	return __pgprot(prot);
271}
272
273#define pgprot_writecombine(prot) pgprot_noncached(prot)
274
275/*
276 * Conversion functions: convert a page and protection to a page entry,
277 * and a page entry and page directory to the page they refer to.
278 */
279#define mk_pte(page, pgprot)	pfn_pte(page_to_pfn(page), pgprot)
280
281static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
282{
283	set_pte(&pte, __pte((pte_val(pte) & _PAGE_CHG_MASK) \
284		| pgprot_val(newprot)));
285
286	return pte;
287}
288
289/*
290 * Conversion functions: convert a page and protection to a page entry,
291 * and a page entry and page directory to the page they refer to.
292 */
293
294static inline void pmd_set(pmd_t * pmdp, pte_t * ptep)
295{
296	pmd_val(*pmdp) = (((unsigned long) ptep) & PAGE_MASK);
297}
298
299#define pmd_page_vaddr(pmd)	\
300	((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
301
302#ifndef CONFIG_DISCONTIGMEM
303#define pmd_page(pmd)	(mem_map + ((pmd_val(pmd) >> PAGE_SHIFT) - PFN_BASE))
304#endif /* !CONFIG_DISCONTIGMEM */
305
306/* to find an entry in a page-table-directory. */
307#define pgd_index(address)	\
308	(((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1))
309
310#define pgd_offset(mm, address)	((mm)->pgd + pgd_index(address))
311
312/* to find an entry in a kernel page-table-directory */
313#define pgd_offset_k(address)	pgd_offset(&init_mm, address)
314
315#define pmd_index(address)	\
316	(((address) >> PMD_SHIFT) & (PTRS_PER_PMD - 1))
317
318#define pte_index(address)	\
319	(((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
320#define pte_offset_kernel(dir, address)	\
321	((pte_t *)pmd_page_vaddr(*(dir)) + pte_index(address))
322#define pte_offset_map(dir, address)	\
323	((pte_t *)page_address(pmd_page(*(dir))) + pte_index(address))
324#define pte_unmap(pte)		do { } while (0)
325
326/* Encode and de-code a swap entry */
327#define __swp_type(x)			(((x).val >> 2) & 0x1f)
328#define __swp_offset(x)			((x).val >> 10)
329#define __swp_entry(type, offset)	\
330	((swp_entry_t) { ((type) << 2) | ((offset) << 10) })
331#define __pte_to_swp_entry(pte)		((swp_entry_t) { pte_val(pte) })
332#define __swp_entry_to_pte(x)		((pte_t) { (x).val })
333
334#endif /* !__ASSEMBLY__ */
335
336/* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
337#define kern_addr_valid(addr)	(1)
338
339#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
340#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
341#define __HAVE_ARCH_PTEP_SET_WRPROTECT
342#define __HAVE_ARCH_PTE_SAME
343#include <asm-generic/pgtable.h>
344
345#endif /* __KERNEL__ */
346
347#endif /* _ASM_M32R_PGTABLE_H */
348