[PATCH] m68k: fix __iounmap for 030
[linux-3.10.git] / 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/config.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
224 /*
225  * Unmap a ioremap()ed region again
226  */
227 void iounmap(void __iomem *addr)
228 {
229 #ifdef CONFIG_AMIGA
230         if ((!MACH_IS_AMIGA) ||
231             (((unsigned long)addr < 0x40000000) ||
232              ((unsigned long)addr > 0x60000000)))
233                         free_io_area((__force void *)addr);
234 #else
235         free_io_area((__force void *)addr);
236 #endif
237 }
238
239 /*
240  * __iounmap unmaps nearly everything, so be careful
241  * it doesn't free currently pointer/page tables anymore but it
242  * wans't used anyway and might be added later.
243  */
244 void __iounmap(void *addr, unsigned long size)
245 {
246         unsigned long virtaddr = (unsigned long)addr;
247         pgd_t *pgd_dir;
248         pmd_t *pmd_dir;
249         pte_t *pte_dir;
250
251         while ((long)size > 0) {
252                 pgd_dir = pgd_offset_k(virtaddr);
253                 if (pgd_bad(*pgd_dir)) {
254                         printk("iounmap: bad pgd(%08lx)\n", pgd_val(*pgd_dir));
255                         pgd_clear(pgd_dir);
256                         return;
257                 }
258                 pmd_dir = pmd_offset(pgd_dir, virtaddr);
259
260                 if (CPU_IS_020_OR_030) {
261                         int pmd_off = (virtaddr/PTRTREESIZE) & 15;
262                         int pmd_type = pmd_dir->pmd[pmd_off] & _DESCTYPE_MASK;
263
264                         if (pmd_type == _PAGE_PRESENT) {
265                                 pmd_dir->pmd[pmd_off] = 0;
266                                 virtaddr += PTRTREESIZE;
267                                 size -= PTRTREESIZE;
268                                 continue;
269                         } else if (pmd_type == 0)
270                                 continue;
271                 }
272
273                 if (pmd_bad(*pmd_dir)) {
274                         printk("iounmap: bad pmd (%08lx)\n", pmd_val(*pmd_dir));
275                         pmd_clear(pmd_dir);
276                         return;
277                 }
278                 pte_dir = pte_offset_kernel(pmd_dir, virtaddr);
279
280                 pte_val(*pte_dir) = 0;
281                 virtaddr += PAGE_SIZE;
282                 size -= PAGE_SIZE;
283         }
284
285         flush_tlb_all();
286 }
287
288 /*
289  * Set new cache mode for some kernel address space.
290  * The caller must push data for that range itself, if such data may already
291  * be in the cache.
292  */
293 void kernel_set_cachemode(void *addr, unsigned long size, int cmode)
294 {
295         unsigned long virtaddr = (unsigned long)addr;
296         pgd_t *pgd_dir;
297         pmd_t *pmd_dir;
298         pte_t *pte_dir;
299
300         if (CPU_IS_040_OR_060) {
301                 switch (cmode) {
302                 case IOMAP_FULL_CACHING:
303                         cmode = _PAGE_CACHE040;
304                         break;
305                 case IOMAP_NOCACHE_SER:
306                 default:
307                         cmode = _PAGE_NOCACHE_S;
308                         break;
309                 case IOMAP_NOCACHE_NONSER:
310                         cmode = _PAGE_NOCACHE;
311                         break;
312                 case IOMAP_WRITETHROUGH:
313                         cmode = _PAGE_CACHE040W;
314                         break;
315                 }
316         } else {
317                 switch (cmode) {
318                 case IOMAP_NOCACHE_SER:
319                 case IOMAP_NOCACHE_NONSER:
320                 default:
321                         cmode = _PAGE_NOCACHE030;
322                         break;
323                 case IOMAP_FULL_CACHING:
324                 case IOMAP_WRITETHROUGH:
325                         cmode = 0;
326                 }
327         }
328
329         while ((long)size > 0) {
330                 pgd_dir = pgd_offset_k(virtaddr);
331                 if (pgd_bad(*pgd_dir)) {
332                         printk("iocachemode: bad pgd(%08lx)\n", pgd_val(*pgd_dir));
333                         pgd_clear(pgd_dir);
334                         return;
335                 }
336                 pmd_dir = pmd_offset(pgd_dir, virtaddr);
337
338                 if (CPU_IS_020_OR_030) {
339                         int pmd_off = (virtaddr/PTRTREESIZE) & 15;
340
341                         if ((pmd_dir->pmd[pmd_off] & _DESCTYPE_MASK) == _PAGE_PRESENT) {
342                                 pmd_dir->pmd[pmd_off] = (pmd_dir->pmd[pmd_off] &
343                                                          _CACHEMASK040) | cmode;
344                                 virtaddr += PTRTREESIZE;
345                                 size -= PTRTREESIZE;
346                                 continue;
347                         }
348                 }
349
350                 if (pmd_bad(*pmd_dir)) {
351                         printk("iocachemode: bad pmd (%08lx)\n", pmd_val(*pmd_dir));
352                         pmd_clear(pmd_dir);
353                         return;
354                 }
355                 pte_dir = pte_offset_kernel(pmd_dir, virtaddr);
356
357                 pte_val(*pte_dir) = (pte_val(*pte_dir) & _CACHEMASK040) | cmode;
358                 virtaddr += PAGE_SIZE;
359                 size -= PAGE_SIZE;
360         }
361
362         flush_tlb_all();
363 }