1 #ifndef _ASM_POWERPC_PGTABLE_PPC32_H
2 #define _ASM_POWERPC_PGTABLE_PPC32_H
3 
4 #include <asm-generic/pgtable-nopmd.h>
5 
6 #ifndef __ASSEMBLY__
7 #include <linux/sched.h>
8 #include <linux/threads.h>
9 #include <asm/io.h>			/* For sub-arch specific PPC_PIN_SIZE */
10 
11 extern unsigned long va_to_phys(unsigned long address);
12 extern pte_t *va_to_pte(unsigned long address);
13 extern unsigned long ioremap_bot;
14 
15 #ifdef CONFIG_44x
16 extern int icache_44x_need_flush;
17 #endif
18 
19 #endif /* __ASSEMBLY__ */
20 
21 /*
22  * The normal case is that PTEs are 32-bits and we have a 1-page
23  * 1024-entry pgdir pointing to 1-page 1024-entry PTE pages.  -- paulus
24  *
25  * For any >32-bit physical address platform, we can use the following
26  * two level page table layout where the pgdir is 8KB and the MS 13 bits
27  * are an index to the second level table.  The combined pgdir/pmd first
28  * level has 2048 entries and the second level has 512 64-bit PTE entries.
29  * -Matt
30  */
31 /* PGDIR_SHIFT determines what a top-level page table entry can map */
32 #define PGDIR_SHIFT	(PAGE_SHIFT + PTE_SHIFT)
33 #define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
34 #define PGDIR_MASK	(~(PGDIR_SIZE-1))
35 
36 /*
37  * entries per page directory level: our page-table tree is two-level, so
38  * we don't really have any PMD directory.
39  */
40 #ifndef __ASSEMBLY__
41 #define PTE_TABLE_SIZE	(sizeof(pte_t) << PTE_SHIFT)
42 #define PGD_TABLE_SIZE	(sizeof(pgd_t) << (32 - PGDIR_SHIFT))
43 #endif	/* __ASSEMBLY__ */
44 
45 #define PTRS_PER_PTE	(1 << PTE_SHIFT)
46 #define PTRS_PER_PMD	1
47 #define PTRS_PER_PGD	(1 << (32 - PGDIR_SHIFT))
48 
49 #define USER_PTRS_PER_PGD	(TASK_SIZE / PGDIR_SIZE)
50 #define FIRST_USER_ADDRESS	0
51 
52 #define pte_ERROR(e) \
53 	printk("%s:%d: bad pte %llx.\n", __FILE__, __LINE__, \
54 		(unsigned long long)pte_val(e))
55 #define pgd_ERROR(e) \
56 	printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
57 
58 /*
59  * This is the bottom of the PKMAP area with HIGHMEM or an arbitrary
60  * value (for now) on others, from where we can start layout kernel
61  * virtual space that goes below PKMAP and FIXMAP
62  */
63 #ifdef CONFIG_HIGHMEM
64 #define KVIRT_TOP	PKMAP_BASE
65 #else
66 #define KVIRT_TOP	(0xfe000000UL)	/* for now, could be FIXMAP_BASE ? */
67 #endif
68 
69 /*
70  * ioremap_bot starts at that address. Early ioremaps move down from there,
71  * until mem_init() at which point this becomes the top of the vmalloc
72  * and ioremap space
73  */
74 #ifdef CONFIG_NOT_COHERENT_CACHE
75 #define IOREMAP_TOP	((KVIRT_TOP - CONFIG_CONSISTENT_SIZE) & PAGE_MASK)
76 #else
77 #define IOREMAP_TOP	KVIRT_TOP
78 #endif
79 
80 /*
81  * Just any arbitrary offset to the start of the vmalloc VM area: the
82  * current 16MB value just means that there will be a 64MB "hole" after the
83  * physical memory until the kernel virtual memory starts.  That means that
84  * any out-of-bounds memory accesses will hopefully be caught.
85  * The vmalloc() routines leaves a hole of 4kB between each vmalloced
86  * area for the same reason. ;)
87  *
88  * We no longer map larger than phys RAM with the BATs so we don't have
89  * to worry about the VMALLOC_OFFSET causing problems.  We do have to worry
90  * about clashes between our early calls to ioremap() that start growing down
91  * from ioremap_base being run into the VM area allocations (growing upwards
92  * from VMALLOC_START).  For this reason we have ioremap_bot to check when
93  * we actually run into our mappings setup in the early boot with the VM
94  * system.  This really does become a problem for machines with good amounts
95  * of RAM.  -- Cort
96  */
97 #define VMALLOC_OFFSET (0x1000000) /* 16M */
98 #ifdef PPC_PIN_SIZE
99 #define VMALLOC_START (((_ALIGN((long)high_memory, PPC_PIN_SIZE) + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
100 #else
101 #define VMALLOC_START ((((long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
102 #endif
103 #define VMALLOC_END	ioremap_bot
104 
105 /*
106  * Bits in a linux-style PTE.  These match the bits in the
107  * (hardware-defined) PowerPC PTE as closely as possible.
108  */
109 
110 #if defined(CONFIG_40x)
111 #include <asm/pte-40x.h>
112 #elif defined(CONFIG_44x)
113 #include <asm/pte-44x.h>
114 #elif defined(CONFIG_FSL_BOOKE) && defined(CONFIG_PTE_64BIT)
115 #include <asm/pte-book3e.h>
116 #elif defined(CONFIG_FSL_BOOKE)
117 #include <asm/pte-fsl-booke.h>
118 #elif defined(CONFIG_8xx)
119 #include <asm/pte-8xx.h>
120 #else /* CONFIG_6xx */
121 #include <asm/pte-hash32.h>
122 #endif
123 
124 /* And here we include common definitions */
125 #include <asm/pte-common.h>
126 
127 #ifndef __ASSEMBLY__
128 
129 #define pte_clear(mm, addr, ptep) \
130 	do { pte_update(ptep, ~_PAGE_HASHPTE, 0); } while (0)
131 
132 #define pmd_none(pmd)		(!pmd_val(pmd))
133 #define	pmd_bad(pmd)		(pmd_val(pmd) & _PMD_BAD)
134 #define	pmd_present(pmd)	(pmd_val(pmd) & _PMD_PRESENT_MASK)
135 #define	pmd_clear(pmdp)		do { pmd_val(*(pmdp)) = 0; } while (0)
136 
137 /*
138  * When flushing the tlb entry for a page, we also need to flush the hash
139  * table entry.  flush_hash_pages is assembler (for speed) in hashtable.S.
140  */
141 extern int flush_hash_pages(unsigned context, unsigned long va,
142 			    unsigned long pmdval, int count);
143 
144 /* Add an HPTE to the hash table */
145 extern void add_hash_page(unsigned context, unsigned long va,
146 			  unsigned long pmdval);
147 
148 /* Flush an entry from the TLB/hash table */
149 extern void flush_hash_entry(struct mm_struct *mm, pte_t *ptep,
150 			     unsigned long address);
151 
152 /*
153  * PTE updates. This function is called whenever an existing
154  * valid PTE is updated. This does -not- include set_pte_at()
155  * which nowadays only sets a new PTE.
156  *
157  * Depending on the type of MMU, we may need to use atomic updates
158  * and the PTE may be either 32 or 64 bit wide. In the later case,
159  * when using atomic updates, only the low part of the PTE is
160  * accessed atomically.
161  *
162  * In addition, on 44x, we also maintain a global flag indicating
163  * that an executable user mapping was modified, which is needed
164  * to properly flush the virtually tagged instruction cache of
165  * those implementations.
166  */
167 #ifndef CONFIG_PTE_64BIT
pte_update(pte_t * p,unsigned long clr,unsigned long set)168 static inline unsigned long pte_update(pte_t *p,
169 				       unsigned long clr,
170 				       unsigned long set)
171 {
172 #ifdef PTE_ATOMIC_UPDATES
173 	unsigned long old, tmp;
174 
175 	__asm__ __volatile__("\
176 1:	lwarx	%0,0,%3\n\
177 	andc	%1,%0,%4\n\
178 	or	%1,%1,%5\n"
179 	PPC405_ERR77(0,%3)
180 "	stwcx.	%1,0,%3\n\
181 	bne-	1b"
182 	: "=&r" (old), "=&r" (tmp), "=m" (*p)
183 	: "r" (p), "r" (clr), "r" (set), "m" (*p)
184 	: "cc" );
185 #else /* PTE_ATOMIC_UPDATES */
186 	unsigned long old = pte_val(*p);
187 	*p = __pte((old & ~clr) | set);
188 #endif /* !PTE_ATOMIC_UPDATES */
189 
190 #ifdef CONFIG_44x
191 	if ((old & _PAGE_USER) && (old & _PAGE_EXEC))
192 		icache_44x_need_flush = 1;
193 #endif
194 	return old;
195 }
196 #else /* CONFIG_PTE_64BIT */
pte_update(pte_t * p,unsigned long clr,unsigned long set)197 static inline unsigned long long pte_update(pte_t *p,
198 					    unsigned long clr,
199 					    unsigned long set)
200 {
201 #ifdef PTE_ATOMIC_UPDATES
202 	unsigned long long old;
203 	unsigned long tmp;
204 
205 	__asm__ __volatile__("\
206 1:	lwarx	%L0,0,%4\n\
207 	lwzx	%0,0,%3\n\
208 	andc	%1,%L0,%5\n\
209 	or	%1,%1,%6\n"
210 	PPC405_ERR77(0,%3)
211 "	stwcx.	%1,0,%4\n\
212 	bne-	1b"
213 	: "=&r" (old), "=&r" (tmp), "=m" (*p)
214 	: "r" (p), "r" ((unsigned long)(p) + 4), "r" (clr), "r" (set), "m" (*p)
215 	: "cc" );
216 #else /* PTE_ATOMIC_UPDATES */
217 	unsigned long long old = pte_val(*p);
218 	*p = __pte((old & ~(unsigned long long)clr) | set);
219 #endif /* !PTE_ATOMIC_UPDATES */
220 
221 #ifdef CONFIG_44x
222 	if ((old & _PAGE_USER) && (old & _PAGE_EXEC))
223 		icache_44x_need_flush = 1;
224 #endif
225 	return old;
226 }
227 #endif /* CONFIG_PTE_64BIT */
228 
229 /*
230  * 2.6 calls this without flushing the TLB entry; this is wrong
231  * for our hash-based implementation, we fix that up here.
232  */
233 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
__ptep_test_and_clear_young(unsigned int context,unsigned long addr,pte_t * ptep)234 static inline int __ptep_test_and_clear_young(unsigned int context, unsigned long addr, pte_t *ptep)
235 {
236 	unsigned long old;
237 	old = pte_update(ptep, _PAGE_ACCESSED, 0);
238 #if _PAGE_HASHPTE != 0
239 	if (old & _PAGE_HASHPTE) {
240 		unsigned long ptephys = __pa(ptep) & PAGE_MASK;
241 		flush_hash_pages(context, addr, ptephys, 1);
242 	}
243 #endif
244 	return (old & _PAGE_ACCESSED) != 0;
245 }
246 #define ptep_test_and_clear_young(__vma, __addr, __ptep) \
247 	__ptep_test_and_clear_young((__vma)->vm_mm->context.id, __addr, __ptep)
248 
249 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
ptep_get_and_clear(struct mm_struct * mm,unsigned long addr,pte_t * ptep)250 static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
251 				       pte_t *ptep)
252 {
253 	return __pte(pte_update(ptep, ~_PAGE_HASHPTE, 0));
254 }
255 
256 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
ptep_set_wrprotect(struct mm_struct * mm,unsigned long addr,pte_t * ptep)257 static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr,
258 				      pte_t *ptep)
259 {
260 	pte_update(ptep, (_PAGE_RW | _PAGE_HWWRITE), 0);
261 }
huge_ptep_set_wrprotect(struct mm_struct * mm,unsigned long addr,pte_t * ptep)262 static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
263 					   unsigned long addr, pte_t *ptep)
264 {
265 	ptep_set_wrprotect(mm, addr, ptep);
266 }
267 
268 
__ptep_set_access_flags(pte_t * ptep,pte_t entry)269 static inline void __ptep_set_access_flags(pte_t *ptep, pte_t entry)
270 {
271 	unsigned long bits = pte_val(entry) &
272 		(_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW | _PAGE_EXEC);
273 	pte_update(ptep, 0, bits);
274 }
275 
276 #define __HAVE_ARCH_PTE_SAME
277 #define pte_same(A,B)	(((pte_val(A) ^ pte_val(B)) & ~_PAGE_HASHPTE) == 0)
278 
279 /*
280  * Note that on Book E processors, the pmd contains the kernel virtual
281  * (lowmem) address of the pte page.  The physical address is less useful
282  * because everything runs with translation enabled (even the TLB miss
283  * handler).  On everything else the pmd contains the physical address
284  * of the pte page.  -- paulus
285  */
286 #ifndef CONFIG_BOOKE
287 #define pmd_page_vaddr(pmd)	\
288 	((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
289 #define pmd_page(pmd)		\
290 	pfn_to_page(pmd_val(pmd) >> PAGE_SHIFT)
291 #else
292 #define pmd_page_vaddr(pmd)	\
293 	((unsigned long) (pmd_val(pmd) & PAGE_MASK))
294 #define pmd_page(pmd)		\
295 	pfn_to_page((__pa(pmd_val(pmd)) >> PAGE_SHIFT))
296 #endif
297 
298 /* to find an entry in a kernel page-table-directory */
299 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
300 
301 /* to find an entry in a page-table-directory */
302 #define pgd_index(address)	 ((address) >> PGDIR_SHIFT)
303 #define pgd_offset(mm, address)	 ((mm)->pgd + pgd_index(address))
304 
305 /* Find an entry in the third-level page table.. */
306 #define pte_index(address)		\
307 	(((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
308 #define pte_offset_kernel(dir, addr)	\
309 	((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(addr))
310 #define pte_offset_map(dir, addr)		\
311 	((pte_t *) kmap_atomic(pmd_page(*(dir))) + pte_index(addr))
312 #define pte_unmap(pte)		kunmap_atomic(pte)
313 
314 /*
315  * Encode and decode a swap entry.
316  * Note that the bits we use in a PTE for representing a swap entry
317  * must not include the _PAGE_PRESENT bit, the _PAGE_FILE bit, or the
318  *_PAGE_HASHPTE bit (if used).  -- paulus
319  */
320 #define __swp_type(entry)		((entry).val & 0x1f)
321 #define __swp_offset(entry)		((entry).val >> 5)
322 #define __swp_entry(type, offset)	((swp_entry_t) { (type) | ((offset) << 5) })
323 #define __pte_to_swp_entry(pte)		((swp_entry_t) { pte_val(pte) >> 3 })
324 #define __swp_entry_to_pte(x)		((pte_t) { (x).val << 3 })
325 
326 /* Encode and decode a nonlinear file mapping entry */
327 #define PTE_FILE_MAX_BITS	29
328 #define pte_to_pgoff(pte)	(pte_val(pte) >> 3)
329 #define pgoff_to_pte(off)	((pte_t) { ((off) << 3) | _PAGE_FILE })
330 
331 /*
332  * No page table caches to initialise
333  */
334 #define pgtable_cache_init()	do { } while (0)
335 
336 extern int get_pteptr(struct mm_struct *mm, unsigned long addr, pte_t **ptep,
337 		      pmd_t **pmdp);
338 
339 #endif /* !__ASSEMBLY__ */
340 
341 #endif /* _ASM_POWERPC_PGTABLE_PPC32_H */
342