Merge branch 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik...
[linux-2.6] / arch / m68k / mm / kmap.c
1 /*
2  *  linux/arch/m68k/mm/kmap.c
3  *
4  *  Copyright (C) 1997 Roman Hodek
5  *
6  *  10/01/99 cleaned up the code and changing to the same interface
7  *           used by other architectures                /Roman Zippel
8  */
9
10 #include <linux/module.h>
11 #include <linux/mm.h>
12 #include <linux/kernel.h>
13 #include <linux/string.h>
14 #include <linux/types.h>
15 #include <linux/slab.h>
16 #include <linux/vmalloc.h>
17
18 #include <asm/setup.h>
19 #include <asm/segment.h>
20 #include <asm/page.h>
21 #include <asm/pgalloc.h>
22 #include <asm/io.h>
23 #include <asm/system.h>
24
25 #undef DEBUG
26
27 #define PTRTREESIZE     (256*1024)
28
29 /*
30  * For 040/060 we can use the virtual memory area like other architectures,
31  * but for 020/030 we want to use early termination page descriptor and we
32  * can't mix this with normal page descriptors, so we have to copy that code
33  * (mm/vmalloc.c) and return appriorate aligned addresses.
34  */
35
36 #ifdef CPU_M68040_OR_M68060_ONLY
37
38 #define IO_SIZE         PAGE_SIZE
39
40 static inline struct vm_struct *get_io_area(unsigned long size)
41 {
42         return get_vm_area(size, VM_IOREMAP);
43 }
44
45
46 static inline void free_io_area(void *addr)
47 {
48         vfree((void *)(PAGE_MASK & (unsigned long)addr));
49 }
50
51 #else
52
53 #define IO_SIZE         (256*1024)
54
55 static struct vm_struct *iolist;
56
57 static struct vm_struct *get_io_area(unsigned long size)
58 {
59         unsigned long addr;
60         struct vm_struct **p, *tmp, *area;
61
62         area = (struct vm_struct *)kmalloc(sizeof(*area), GFP_KERNEL);
63         if (!area)
64                 return NULL;
65         addr = KMAP_START;
66         for (p = &iolist; (tmp = *p) ; p = &tmp->next) {
67                 if (size + addr < (unsigned long)tmp->addr)
68                         break;
69                 if (addr > KMAP_END-size)
70                         return NULL;
71                 addr = tmp->size + (unsigned long)tmp->addr;
72         }
73         area->addr = (void *)addr;
74         area->size = size + IO_SIZE;
75         area->next = *p;
76         *p = area;
77         return area;
78 }
79
80 static inline void free_io_area(void *addr)
81 {
82         struct vm_struct **p, *tmp;
83
84         if (!addr)
85                 return;
86         addr = (void *)((unsigned long)addr & -IO_SIZE);
87         for (p = &iolist ; (tmp = *p) ; p = &tmp->next) {
88                 if (tmp->addr == addr) {
89                         *p = tmp->next;
90                         __iounmap(tmp->addr, tmp->size);
91                         kfree(tmp);
92                         return;
93                 }
94         }
95 }
96
97 #endif
98
99 /*
100  * Map some physical address range into the kernel address space. The
101  * code is copied and adapted from map_chunk().
102  */
103 /* Rewritten by Andreas Schwab to remove all races. */
104
105 void __iomem *__ioremap(unsigned long physaddr, unsigned long size, int cacheflag)
106 {
107         struct vm_struct *area;
108         unsigned long virtaddr, retaddr;
109         long offset;
110         pgd_t *pgd_dir;
111         pmd_t *pmd_dir;
112         pte_t *pte_dir;
113
114         /*
115          * Don't allow mappings that wrap..
116          */
117         if (!size || size > physaddr + size)
118                 return NULL;
119
120 #ifdef CONFIG_AMIGA
121         if (MACH_IS_AMIGA) {
122                 if ((physaddr >= 0x40000000) && (physaddr + size < 0x60000000)
123                     && (cacheflag == IOMAP_NOCACHE_SER))
124                         return (void __iomem *)physaddr;
125         }
126 #endif
127
128 #ifdef DEBUG
129         printk("ioremap: 0x%lx,0x%lx(%d) - ", physaddr, size, cacheflag);
130 #endif
131         /*
132          * Mappings have to be aligned
133          */
134         offset = physaddr & (IO_SIZE - 1);
135         physaddr &= -IO_SIZE;
136         size = (size + offset + IO_SIZE - 1) & -IO_SIZE;
137
138         /*
139          * Ok, go for it..
140          */
141         area = get_io_area(size);
142         if (!area)
143                 return NULL;
144
145         virtaddr = (unsigned long)area->addr;
146         retaddr = virtaddr + offset;
147 #ifdef DEBUG
148         printk("0x%lx,0x%lx,0x%lx", physaddr, virtaddr, retaddr);
149 #endif
150
151         /*
152          * add cache and table flags to physical address
153          */
154         if (CPU_IS_040_OR_060) {
155                 physaddr |= (_PAGE_PRESENT | _PAGE_GLOBAL040 |
156                              _PAGE_ACCESSED | _PAGE_DIRTY);
157                 switch (cacheflag) {
158                 case IOMAP_FULL_CACHING:
159                         physaddr |= _PAGE_CACHE040;
160                         break;
161                 case IOMAP_NOCACHE_SER:
162                 default:
163                         physaddr |= _PAGE_NOCACHE_S;
164                         break;
165                 case IOMAP_NOCACHE_NONSER:
166                         physaddr |= _PAGE_NOCACHE;
167                         break;
168                 case IOMAP_WRITETHROUGH:
169                         physaddr |= _PAGE_CACHE040W;
170                         break;
171                 }
172         } else {
173                 physaddr |= (_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_DIRTY);
174                 switch (cacheflag) {
175                 case IOMAP_NOCACHE_SER:
176                 case IOMAP_NOCACHE_NONSER:
177                 default:
178                         physaddr |= _PAGE_NOCACHE030;
179                         break;
180                 case IOMAP_FULL_CACHING:
181                 case IOMAP_WRITETHROUGH:
182                         break;
183                 }
184         }
185
186         while ((long)size > 0) {
187 #ifdef DEBUG
188                 if (!(virtaddr & (PTRTREESIZE-1)))
189                         printk ("\npa=%#lx va=%#lx ", physaddr, virtaddr);
190 #endif
191                 pgd_dir = pgd_offset_k(virtaddr);
192                 pmd_dir = pmd_alloc(&init_mm, pgd_dir, virtaddr);
193                 if (!pmd_dir) {
194                         printk("ioremap: no mem for pmd_dir\n");
195                         return NULL;
196                 }
197
198                 if (CPU_IS_020_OR_030) {
199                         pmd_dir->pmd[(virtaddr/PTRTREESIZE) & 15] = physaddr;
200                         physaddr += PTRTREESIZE;
201                         virtaddr += PTRTREESIZE;
202                         size -= PTRTREESIZE;
203                 } else {
204                         pte_dir = pte_alloc_kernel(pmd_dir, virtaddr);
205                         if (!pte_dir) {
206                                 printk("ioremap: no mem for pte_dir\n");
207                                 return NULL;
208                         }
209
210                         pte_val(*pte_dir) = physaddr;
211                         virtaddr += PAGE_SIZE;
212                         physaddr += PAGE_SIZE;
213                         size -= PAGE_SIZE;
214                 }
215         }
216 #ifdef DEBUG
217         printk("\n");
218 #endif
219         flush_tlb_all();
220
221         return (void __iomem *)retaddr;
222 }
223 EXPORT_SYMBOL(__ioremap);
224
225 /*
226  * Unmap a ioremap()ed region again
227  */
228 void iounmap(void __iomem *addr)
229 {
230 #ifdef CONFIG_AMIGA
231         if ((!MACH_IS_AMIGA) ||
232             (((unsigned long)addr < 0x40000000) ||
233              ((unsigned long)addr > 0x60000000)))
234                         free_io_area((__force void *)addr);
235 #else
236         free_io_area((__force void *)addr);
237 #endif
238 }
239 EXPORT_SYMBOL(iounmap);
240
241 /*
242  * __iounmap unmaps nearly everything, so be careful
243  * it doesn't free currently pointer/page tables anymore but it
244  * wans't used anyway and might be added later.
245  */
246 void __iounmap(void *addr, unsigned long size)
247 {
248         unsigned long virtaddr = (unsigned long)addr;
249         pgd_t *pgd_dir;
250         pmd_t *pmd_dir;
251         pte_t *pte_dir;
252
253         while ((long)size > 0) {
254                 pgd_dir = pgd_offset_k(virtaddr);
255                 if (pgd_bad(*pgd_dir)) {
256                         printk("iounmap: bad pgd(%08lx)\n", pgd_val(*pgd_dir));
257                         pgd_clear(pgd_dir);
258                         return;
259                 }
260                 pmd_dir = pmd_offset(pgd_dir, virtaddr);
261
262                 if (CPU_IS_020_OR_030) {
263                         int pmd_off = (virtaddr/PTRTREESIZE) & 15;
264                         int pmd_type = pmd_dir->pmd[pmd_off] & _DESCTYPE_MASK;
265
266                         if (pmd_type == _PAGE_PRESENT) {
267                                 pmd_dir->pmd[pmd_off] = 0;
268                                 virtaddr += PTRTREESIZE;
269                                 size -= PTRTREESIZE;
270                                 continue;
271                         } else if (pmd_type == 0)
272                                 continue;
273                 }
274
275                 if (pmd_bad(*pmd_dir)) {
276                         printk("iounmap: bad pmd (%08lx)\n", pmd_val(*pmd_dir));
277                         pmd_clear(pmd_dir);
278                         return;
279                 }
280                 pte_dir = pte_offset_kernel(pmd_dir, virtaddr);
281
282                 pte_val(*pte_dir) = 0;
283                 virtaddr += PAGE_SIZE;
284                 size -= PAGE_SIZE;
285         }
286
287         flush_tlb_all();
288 }
289
290 /*
291  * Set new cache mode for some kernel address space.
292  * The caller must push data for that range itself, if such data may already
293  * be in the cache.
294  */
295 void kernel_set_cachemode(void *addr, unsigned long size, int cmode)
296 {
297         unsigned long virtaddr = (unsigned long)addr;
298         pgd_t *pgd_dir;
299         pmd_t *pmd_dir;
300         pte_t *pte_dir;
301
302         if (CPU_IS_040_OR_060) {
303                 switch (cmode) {
304                 case IOMAP_FULL_CACHING:
305                         cmode = _PAGE_CACHE040;
306                         break;
307                 case IOMAP_NOCACHE_SER:
308                 default:
309                         cmode = _PAGE_NOCACHE_S;
310                         break;
311                 case IOMAP_NOCACHE_NONSER:
312                         cmode = _PAGE_NOCACHE;
313                         break;
314                 case IOMAP_WRITETHROUGH:
315                         cmode = _PAGE_CACHE040W;
316                         break;
317                 }
318         } else {
319                 switch (cmode) {
320                 case IOMAP_NOCACHE_SER:
321                 case IOMAP_NOCACHE_NONSER:
322                 default:
323                         cmode = _PAGE_NOCACHE030;
324                         break;
325                 case IOMAP_FULL_CACHING:
326                 case IOMAP_WRITETHROUGH:
327                         cmode = 0;
328                 }
329         }
330
331         while ((long)size > 0) {
332                 pgd_dir = pgd_offset_k(virtaddr);
333                 if (pgd_bad(*pgd_dir)) {
334                         printk("iocachemode: bad pgd(%08lx)\n", pgd_val(*pgd_dir));
335                         pgd_clear(pgd_dir);
336                         return;
337                 }
338                 pmd_dir = pmd_offset(pgd_dir, virtaddr);
339
340                 if (CPU_IS_020_OR_030) {
341                         int pmd_off = (virtaddr/PTRTREESIZE) & 15;
342
343                         if ((pmd_dir->pmd[pmd_off] & _DESCTYPE_MASK) == _PAGE_PRESENT) {
344                                 pmd_dir->pmd[pmd_off] = (pmd_dir->pmd[pmd_off] &
345                                                          _CACHEMASK040) | cmode;
346                                 virtaddr += PTRTREESIZE;
347                                 size -= PTRTREESIZE;
348                                 continue;
349                         }
350                 }
351
352                 if (pmd_bad(*pmd_dir)) {
353                         printk("iocachemode: bad pmd (%08lx)\n", pmd_val(*pmd_dir));
354                         pmd_clear(pmd_dir);
355                         return;
356                 }
357                 pte_dir = pte_offset_kernel(pmd_dir, virtaddr);
358
359                 pte_val(*pte_dir) = (pte_val(*pte_dir) & _CACHEMASK040) | cmode;
360                 virtaddr += PAGE_SIZE;
361                 size -= PAGE_SIZE;
362         }
363
364         flush_tlb_all();
365 }
366 EXPORT_SYMBOL(kernel_set_cachemode);