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1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __ASM_SH_PGTABLE_32_H
3 #define __ASM_SH_PGTABLE_32_H
4
5 /*
6 * Linux PTEL encoding.
7 *
8 * Hardware and software bit definitions for the PTEL value (see below for
9 * notes on SH-X2 MMUs and 64-bit PTEs):
10 *
11 * - Bits 0 and 7 are reserved on SH-3 (_PAGE_WT and _PAGE_SZ1 on SH-4).
12 *
13 * - Bit 1 is the SH-bit, but is unused on SH-3 due to an MMU bug (the
14 * hardware PTEL value can't have the SH-bit set when MMUCR.IX is set,
15 * which is the default in cpu-sh3/mmu_context.h:MMU_CONTROL_INIT).
16 *
17 * In order to keep this relatively clean, do not use these for defining
18 * SH-3 specific flags until all of the other unused bits have been
19 * exhausted.
20 *
21 * - Bit 9 is reserved by everyone and used by _PAGE_PROTNONE.
22 *
23 * - Bits 10 and 11 are low bits of the PPN that are reserved on >= 4K pages.
24 * Bit 10 is used for _PAGE_ACCESSED, and bit 11 is used for _PAGE_SPECIAL.
25 *
26 * - On 29 bit platforms, bits 31 to 29 are used for the space attributes
27 * and timing control which (together with bit 0) are moved into the
28 * old-style PTEA on the parts that support it.
29 *
30 * SH-X2 MMUs and extended PTEs
31 *
32 * SH-X2 supports an extended mode TLB with split data arrays due to the
33 * number of bits needed for PR and SZ (now EPR and ESZ) encodings. The PR and
34 * SZ bit placeholders still exist in data array 1, but are implemented as
35 * reserved bits, with the real logic existing in data array 2.
36 *
37 * The downside to this is that we can no longer fit everything in to a 32-bit
38 * PTE encoding, so a 64-bit pte_t is necessary for these parts. On the plus
39 * side, this gives us quite a few spare bits to play with for future usage.
40 */
41 /* Legacy and compat mode bits */
42 #define _PAGE_WT 0x001 /* WT-bit on SH-4, 0 on SH-3 */
43 #define _PAGE_HW_SHARED 0x002 /* SH-bit : shared among processes */
44 #define _PAGE_DIRTY 0x004 /* D-bit : page changed */
45 #define _PAGE_CACHABLE 0x008 /* C-bit : cachable */
46 #define _PAGE_SZ0 0x010 /* SZ0-bit : Size of page */
47 #define _PAGE_RW 0x020 /* PR0-bit : write access allowed */
48 #define _PAGE_USER 0x040 /* PR1-bit : user space access allowed*/
49 #define _PAGE_SZ1 0x080 /* SZ1-bit : Size of page (on SH-4) */
50 #define _PAGE_PRESENT 0x100 /* V-bit : page is valid */
51 #define _PAGE_PROTNONE 0x200 /* software: if not present */
52 #define _PAGE_ACCESSED 0x400 /* software: page referenced */
53 #define _PAGE_SPECIAL 0x800 /* software: special page */
54
55 #define _PAGE_SZ_MASK (_PAGE_SZ0 | _PAGE_SZ1)
56 #define _PAGE_PR_MASK (_PAGE_RW | _PAGE_USER)
57
58 /* Extended mode bits */
59 #define _PAGE_EXT_ESZ0 0x0010 /* ESZ0-bit: Size of page */
60 #define _PAGE_EXT_ESZ1 0x0020 /* ESZ1-bit: Size of page */
61 #define _PAGE_EXT_ESZ2 0x0040 /* ESZ2-bit: Size of page */
62 #define _PAGE_EXT_ESZ3 0x0080 /* ESZ3-bit: Size of page */
63
64 #define _PAGE_EXT_USER_EXEC 0x0100 /* EPR0-bit: User space executable */
65 #define _PAGE_EXT_USER_WRITE 0x0200 /* EPR1-bit: User space writable */
66 #define _PAGE_EXT_USER_READ 0x0400 /* EPR2-bit: User space readable */
67
68 #define _PAGE_EXT_KERN_EXEC 0x0800 /* EPR3-bit: Kernel space executable */
69 #define _PAGE_EXT_KERN_WRITE 0x1000 /* EPR4-bit: Kernel space writable */
70 #define _PAGE_EXT_KERN_READ 0x2000 /* EPR5-bit: Kernel space readable */
71
72 #define _PAGE_EXT_WIRED 0x4000 /* software: Wire TLB entry */
73
74 /* Wrapper for extended mode pgprot twiddling */
75 #define _PAGE_EXT(x) ((unsigned long long)(x) << 32)
76
77 #ifdef CONFIG_X2TLB
78 #define _PAGE_PCC_MASK 0x00000000 /* No legacy PTEA support */
79 #else
80
81 /* software: moves to PTEA.TC (Timing Control) */
82 #define _PAGE_PCC_AREA5 0x00000000 /* use BSC registers for area5 */
83 #define _PAGE_PCC_AREA6 0x80000000 /* use BSC registers for area6 */
84
85 /* software: moves to PTEA.SA[2:0] (Space Attributes) */
86 #define _PAGE_PCC_IODYN 0x00000001 /* IO space, dynamically sized bus */
87 #define _PAGE_PCC_IO8 0x20000000 /* IO space, 8 bit bus */
88 #define _PAGE_PCC_IO16 0x20000001 /* IO space, 16 bit bus */
89 #define _PAGE_PCC_COM8 0x40000000 /* Common Memory space, 8 bit bus */
90 #define _PAGE_PCC_COM16 0x40000001 /* Common Memory space, 16 bit bus */
91 #define _PAGE_PCC_ATR8 0x60000000 /* Attribute Memory space, 8 bit bus */
92 #define _PAGE_PCC_ATR16 0x60000001 /* Attribute Memory space, 6 bit bus */
93
94 #define _PAGE_PCC_MASK 0xe0000001
95
96 /* copy the ptea attributes */
97 static inline unsigned long copy_ptea_attributes(unsigned long x)
98 {
99 return ((x >> 28) & 0xe) | (x & 0x1);
100 }
101 #endif
102
103 /* Mask which drops unused bits from the PTEL value */
104 #if defined(CONFIG_CPU_SH3)
105 #define _PAGE_CLEAR_FLAGS (_PAGE_PROTNONE | _PAGE_ACCESSED| \
106 _PAGE_SZ1 | _PAGE_HW_SHARED)
107 #elif defined(CONFIG_X2TLB)
108 /* Get rid of the legacy PR/SZ bits when using extended mode */
109 #define _PAGE_CLEAR_FLAGS (_PAGE_PROTNONE | _PAGE_ACCESSED | \
110 _PAGE_PR_MASK | _PAGE_SZ_MASK)
111 #else
112 #define _PAGE_CLEAR_FLAGS (_PAGE_PROTNONE | _PAGE_ACCESSED)
113 #endif
114
115 #define _PAGE_FLAGS_HARDWARE_MASK (phys_addr_mask() & ~(_PAGE_CLEAR_FLAGS))
116
117 /* Hardware flags, page size encoding */
118 #if !defined(CONFIG_MMU)
119 # define _PAGE_FLAGS_HARD 0ULL
120 #elif defined(CONFIG_X2TLB)
121 # if defined(CONFIG_PAGE_SIZE_4KB)
122 # define _PAGE_FLAGS_HARD _PAGE_EXT(_PAGE_EXT_ESZ0)
123 # elif defined(CONFIG_PAGE_SIZE_8KB)
124 # define _PAGE_FLAGS_HARD _PAGE_EXT(_PAGE_EXT_ESZ1)
125 # elif defined(CONFIG_PAGE_SIZE_64KB)
126 # define _PAGE_FLAGS_HARD _PAGE_EXT(_PAGE_EXT_ESZ2)
127 # endif
128 #else
129 # if defined(CONFIG_PAGE_SIZE_4KB)
130 # define _PAGE_FLAGS_HARD _PAGE_SZ0
131 # elif defined(CONFIG_PAGE_SIZE_64KB)
132 # define _PAGE_FLAGS_HARD _PAGE_SZ1
133 # endif
134 #endif
135
136 #if defined(CONFIG_X2TLB)
137 # if defined(CONFIG_HUGETLB_PAGE_SIZE_64K)
138 # define _PAGE_SZHUGE (_PAGE_EXT_ESZ2)
139 # elif defined(CONFIG_HUGETLB_PAGE_SIZE_256K)
140 # define _PAGE_SZHUGE (_PAGE_EXT_ESZ0 | _PAGE_EXT_ESZ2)
141 # elif defined(CONFIG_HUGETLB_PAGE_SIZE_1MB)
142 # define _PAGE_SZHUGE (_PAGE_EXT_ESZ0 | _PAGE_EXT_ESZ1 | _PAGE_EXT_ESZ2)
143 # elif defined(CONFIG_HUGETLB_PAGE_SIZE_4MB)
144 # define _PAGE_SZHUGE (_PAGE_EXT_ESZ3)
145 # elif defined(CONFIG_HUGETLB_PAGE_SIZE_64MB)
146 # define _PAGE_SZHUGE (_PAGE_EXT_ESZ2 | _PAGE_EXT_ESZ3)
147 # endif
148 # define _PAGE_WIRED (_PAGE_EXT(_PAGE_EXT_WIRED))
149 #else
150 # if defined(CONFIG_HUGETLB_PAGE_SIZE_64K)
151 # define _PAGE_SZHUGE (_PAGE_SZ1)
152 # elif defined(CONFIG_HUGETLB_PAGE_SIZE_1MB)
153 # define _PAGE_SZHUGE (_PAGE_SZ0 | _PAGE_SZ1)
154 # endif
155 # define _PAGE_WIRED (0)
156 #endif
157
158 /*
159 * Stub out _PAGE_SZHUGE if we don't have a good definition for it,
160 * to make pte_mkhuge() happy.
161 */
162 #ifndef _PAGE_SZHUGE
163 # define _PAGE_SZHUGE (_PAGE_FLAGS_HARD)
164 #endif
165
166 /*
167 * Mask of bits that are to be preserved across pgprot changes.
168 */
169 #define _PAGE_CHG_MASK \
170 (PTE_MASK | _PAGE_ACCESSED | _PAGE_CACHABLE | \
171 _PAGE_DIRTY | _PAGE_SPECIAL)
172
173 #ifndef __ASSEMBLY__
174
175 #if defined(CONFIG_X2TLB) /* SH-X2 TLB */
176 #define PAGE_NONE __pgprot(_PAGE_PROTNONE | _PAGE_CACHABLE | \
177 _PAGE_ACCESSED | _PAGE_FLAGS_HARD)
178
179 #define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \
180 _PAGE_CACHABLE | _PAGE_FLAGS_HARD | \
181 _PAGE_EXT(_PAGE_EXT_KERN_READ | \
182 _PAGE_EXT_KERN_WRITE | \
183 _PAGE_EXT_USER_READ | \
184 _PAGE_EXT_USER_WRITE))
185
186 #define PAGE_EXECREAD __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \
187 _PAGE_CACHABLE | _PAGE_FLAGS_HARD | \
188 _PAGE_EXT(_PAGE_EXT_KERN_EXEC | \
189 _PAGE_EXT_KERN_READ | \
190 _PAGE_EXT_USER_EXEC | \
191 _PAGE_EXT_USER_READ))
192
193 #define PAGE_COPY PAGE_EXECREAD
194
195 #define PAGE_READONLY __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \
196 _PAGE_CACHABLE | _PAGE_FLAGS_HARD | \
197 _PAGE_EXT(_PAGE_EXT_KERN_READ | \
198 _PAGE_EXT_USER_READ))
199
200 #define PAGE_WRITEONLY __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \
201 _PAGE_CACHABLE | _PAGE_FLAGS_HARD | \
202 _PAGE_EXT(_PAGE_EXT_KERN_WRITE | \
203 _PAGE_EXT_USER_WRITE))
204
205 #define PAGE_RWX __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \
206 _PAGE_CACHABLE | _PAGE_FLAGS_HARD | \
207 _PAGE_EXT(_PAGE_EXT_KERN_WRITE | \
208 _PAGE_EXT_KERN_READ | \
209 _PAGE_EXT_KERN_EXEC | \
210 _PAGE_EXT_USER_WRITE | \
211 _PAGE_EXT_USER_READ | \
212 _PAGE_EXT_USER_EXEC))
213
214 #define PAGE_KERNEL __pgprot(_PAGE_PRESENT | _PAGE_CACHABLE | \
215 _PAGE_DIRTY | _PAGE_ACCESSED | \
216 _PAGE_HW_SHARED | _PAGE_FLAGS_HARD | \
217 _PAGE_EXT(_PAGE_EXT_KERN_READ | \
218 _PAGE_EXT_KERN_WRITE | \
219 _PAGE_EXT_KERN_EXEC))
220
221 #define PAGE_KERNEL_NOCACHE \
222 __pgprot(_PAGE_PRESENT | _PAGE_DIRTY | \
223 _PAGE_ACCESSED | _PAGE_HW_SHARED | \
224 _PAGE_FLAGS_HARD | \
225 _PAGE_EXT(_PAGE_EXT_KERN_READ | \
226 _PAGE_EXT_KERN_WRITE | \
227 _PAGE_EXT_KERN_EXEC))
228
229 #define PAGE_KERNEL_RO __pgprot(_PAGE_PRESENT | _PAGE_CACHABLE | \
230 _PAGE_DIRTY | _PAGE_ACCESSED | \
231 _PAGE_HW_SHARED | _PAGE_FLAGS_HARD | \
232 _PAGE_EXT(_PAGE_EXT_KERN_READ | \
233 _PAGE_EXT_KERN_EXEC))
234
235 #define PAGE_KERNEL_PCC(slot, type) \
236 __pgprot(0)
237
238 #elif defined(CONFIG_MMU) /* SH-X TLB */
239 #define PAGE_NONE __pgprot(_PAGE_PROTNONE | _PAGE_CACHABLE | \
240 _PAGE_ACCESSED | _PAGE_FLAGS_HARD)
241
242 #define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | \
243 _PAGE_CACHABLE | _PAGE_ACCESSED | \
244 _PAGE_FLAGS_HARD)
245
246 #define PAGE_COPY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_CACHABLE | \
247 _PAGE_ACCESSED | _PAGE_FLAGS_HARD)
248
249 #define PAGE_READONLY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_CACHABLE | \
250 _PAGE_ACCESSED | _PAGE_FLAGS_HARD)
251
252 #define PAGE_EXECREAD PAGE_READONLY
253 #define PAGE_RWX PAGE_SHARED
254 #define PAGE_WRITEONLY PAGE_SHARED
255
256 #define PAGE_KERNEL __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_CACHABLE | \
257 _PAGE_DIRTY | _PAGE_ACCESSED | \
258 _PAGE_HW_SHARED | _PAGE_FLAGS_HARD)
259
260 #define PAGE_KERNEL_NOCACHE \
261 __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | \
262 _PAGE_ACCESSED | _PAGE_HW_SHARED | \
263 _PAGE_FLAGS_HARD)
264
265 #define PAGE_KERNEL_RO __pgprot(_PAGE_PRESENT | _PAGE_CACHABLE | \
266 _PAGE_DIRTY | _PAGE_ACCESSED | \
267 _PAGE_HW_SHARED | _PAGE_FLAGS_HARD)
268
269 #define PAGE_KERNEL_PCC(slot, type) \
270 __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | \
271 _PAGE_ACCESSED | _PAGE_FLAGS_HARD | \
272 (slot ? _PAGE_PCC_AREA5 : _PAGE_PCC_AREA6) | \
273 (type))
274 #else /* no mmu */
275 #define PAGE_NONE __pgprot(0)
276 #define PAGE_SHARED __pgprot(0)
277 #define PAGE_COPY __pgprot(0)
278 #define PAGE_EXECREAD __pgprot(0)
279 #define PAGE_RWX __pgprot(0)
280 #define PAGE_READONLY __pgprot(0)
281 #define PAGE_WRITEONLY __pgprot(0)
282 #define PAGE_KERNEL __pgprot(0)
283 #define PAGE_KERNEL_NOCACHE __pgprot(0)
284 #define PAGE_KERNEL_RO __pgprot(0)
285
286 #define PAGE_KERNEL_PCC(slot, type) \
287 __pgprot(0)
288 #endif
289
290 #endif /* __ASSEMBLY__ */
291
292 #ifndef __ASSEMBLY__
293
294 /*
295 * Certain architectures need to do special things when PTEs
296 * within a page table are directly modified. Thus, the following
297 * hook is made available.
298 */
299 #ifdef CONFIG_X2TLB
300 static inline void set_pte(pte_t *ptep, pte_t pte)
301 {
302 ptep->pte_high = pte.pte_high;
303 smp_wmb();
304 ptep->pte_low = pte.pte_low;
305 }
306 #else
307 #define set_pte(pteptr, pteval) (*(pteptr) = pteval)
308 #endif
309
310 #define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
311
312 /*
313 * (pmds are folded into pgds so this doesn't get actually called,
314 * but the define is needed for a generic inline function.)
315 */
316 #define set_pmd(pmdptr, pmdval) (*(pmdptr) = pmdval)
317
318 #define pfn_pte(pfn, prot) \
319 __pte(((unsigned long long)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
320 #define pfn_pmd(pfn, prot) \
321 __pmd(((unsigned long long)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
322
323 #define pte_none(x) (!pte_val(x))
324 #define pte_present(x) ((x).pte_low & (_PAGE_PRESENT | _PAGE_PROTNONE))
325
326 #define pte_clear(mm,addr,xp) do { set_pte_at(mm, addr, xp, __pte(0)); } while (0)
327
328 #define pmd_none(x) (!pmd_val(x))
329 #define pmd_present(x) (pmd_val(x))
330 #define pmd_clear(xp) do { set_pmd(xp, __pmd(0)); } while (0)
331 #define pmd_bad(x) (pmd_val(x) & ~PAGE_MASK)
332
333 #define pages_to_mb(x) ((x) >> (20-PAGE_SHIFT))
334 #define pte_page(x) pfn_to_page(pte_pfn(x))
335
336 /*
337 * The following only work if pte_present() is true.
338 * Undefined behaviour if not..
339 */
340 #define pte_not_present(pte) (!((pte).pte_low & _PAGE_PRESENT))
341 #define pte_dirty(pte) ((pte).pte_low & _PAGE_DIRTY)
342 #define pte_young(pte) ((pte).pte_low & _PAGE_ACCESSED)
343 #define pte_special(pte) ((pte).pte_low & _PAGE_SPECIAL)
344
345 #ifdef CONFIG_X2TLB
346 #define pte_write(pte) \
347 ((pte).pte_high & (_PAGE_EXT_USER_WRITE | _PAGE_EXT_KERN_WRITE))
348 #else
349 #define pte_write(pte) ((pte).pte_low & _PAGE_RW)
350 #endif
351
352 #define PTE_BIT_FUNC(h,fn,op) \
353 static inline pte_t pte_##fn(pte_t pte) { pte.pte_##h op; return pte; }
354
355 #ifdef CONFIG_X2TLB
356 /*
357 * We cheat a bit in the SH-X2 TLB case. As the permission bits are
358 * individually toggled (and user permissions are entirely decoupled from
359 * kernel permissions), we attempt to couple them a bit more sanely here.
360 */
361 PTE_BIT_FUNC(high, wrprotect, &= ~(_PAGE_EXT_USER_WRITE | _PAGE_EXT_KERN_WRITE));
362 PTE_BIT_FUNC(high, mkwrite, |= _PAGE_EXT_USER_WRITE | _PAGE_EXT_KERN_WRITE);
363 PTE_BIT_FUNC(high, mkhuge, |= _PAGE_SZHUGE);
364 #else
365 PTE_BIT_FUNC(low, wrprotect, &= ~_PAGE_RW);
366 PTE_BIT_FUNC(low, mkwrite, |= _PAGE_RW);
367 PTE_BIT_FUNC(low, mkhuge, |= _PAGE_SZHUGE);
368 #endif
369
370 PTE_BIT_FUNC(low, mkclean, &= ~_PAGE_DIRTY);
371 PTE_BIT_FUNC(low, mkdirty, |= _PAGE_DIRTY);
372 PTE_BIT_FUNC(low, mkold, &= ~_PAGE_ACCESSED);
373 PTE_BIT_FUNC(low, mkyoung, |= _PAGE_ACCESSED);
374 PTE_BIT_FUNC(low, mkspecial, |= _PAGE_SPECIAL);
375
376 /*
377 * Macro and implementation to make a page protection as uncachable.
378 */
379 #define pgprot_writecombine(prot) \
380 __pgprot(pgprot_val(prot) & ~_PAGE_CACHABLE)
381
382 #define pgprot_noncached pgprot_writecombine
383
384 /*
385 * Conversion functions: convert a page and protection to a page entry,
386 * and a page entry and page directory to the page they refer to.
387 *
388 * extern pte_t mk_pte(struct page *page, pgprot_t pgprot)
389 */
390 #define mk_pte(page, pgprot) pfn_pte(page_to_pfn(page), (pgprot))
391
392 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
393 {
394 pte.pte_low &= _PAGE_CHG_MASK;
395 pte.pte_low |= pgprot_val(newprot);
396
397 #ifdef CONFIG_X2TLB
398 pte.pte_high |= pgprot_val(newprot) >> 32;
399 #endif
400
401 return pte;
402 }
403
404 #define pmd_page_vaddr(pmd) ((unsigned long)pmd_val(pmd))
405 #define pmd_page(pmd) (virt_to_page(pmd_val(pmd)))
406
407 /* to find an entry in a page-table-directory. */
408 #define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
409 #define pgd_offset(mm, address) ((mm)->pgd + pgd_index(address))
410 #define __pgd_offset(address) pgd_index(address)
411
412 /* to find an entry in a kernel page-table-directory */
413 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
414
415 #define __pud_offset(address) (((address) >> PUD_SHIFT) & (PTRS_PER_PUD-1))
416 #define __pmd_offset(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
417
418 /* Find an entry in the third-level page table.. */
419 #define pte_index(address) ((address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
420 #define __pte_offset(address) pte_index(address)
421
422 #define pte_offset_kernel(dir, address) \
423 ((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(address))
424 #define pte_offset_map(dir, address) pte_offset_kernel(dir, address)
425 #define pte_unmap(pte) do { } while (0)
426
427 #ifdef CONFIG_X2TLB
428 #define pte_ERROR(e) \
429 printk("%s:%d: bad pte %p(%08lx%08lx).\n", __FILE__, __LINE__, \
430 &(e), (e).pte_high, (e).pte_low)
431 #define pgd_ERROR(e) \
432 printk("%s:%d: bad pgd %016llx.\n", __FILE__, __LINE__, pgd_val(e))
433 #else
434 #define pte_ERROR(e) \
435 printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
436 #define pgd_ERROR(e) \
437 printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
438 #endif
439
440 /*
441 * Encode and de-code a swap entry
442 *
443 * Constraints:
444 * _PAGE_PRESENT at bit 8
445 * _PAGE_PROTNONE at bit 9
446 *
447 * For the normal case, we encode the swap type into bits 0:7 and the
448 * swap offset into bits 10:30. For the 64-bit PTE case, we keep the
449 * preserved bits in the low 32-bits and use the upper 32 as the swap
450 * offset (along with a 5-bit type), following the same approach as x86
451 * PAE. This keeps the logic quite simple.
452 *
453 * As is evident by the Alpha code, if we ever get a 64-bit unsigned
454 * long (swp_entry_t) to match up with the 64-bit PTEs, this all becomes
455 * much cleaner..
456 *
457 * NOTE: We should set ZEROs at the position of _PAGE_PRESENT
458 * and _PAGE_PROTNONE bits
459 */
460 #ifdef CONFIG_X2TLB
461 #define __swp_type(x) ((x).val & 0x1f)
462 #define __swp_offset(x) ((x).val >> 5)
463 #define __swp_entry(type, offset) ((swp_entry_t){ (type) | (offset) << 5})
464 #define __pte_to_swp_entry(pte) ((swp_entry_t){ (pte).pte_high })
465 #define __swp_entry_to_pte(x) ((pte_t){ 0, (x).val })
466
467 #else
468 #define __swp_type(x) ((x).val & 0xff)
469 #define __swp_offset(x) ((x).val >> 10)
470 #define __swp_entry(type, offset) ((swp_entry_t){(type) | (offset) <<10})
471
472 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) >> 1 })
473 #define __swp_entry_to_pte(x) ((pte_t) { (x).val << 1 })
474 #endif
475
476 #endif /* __ASSEMBLY__ */
477 #endif /* __ASM_SH_PGTABLE_32_H */