aboutsummaryrefslogtreecommitdiffstats
path: root/arch/m68k/mm/kmap_mm.c
blob: 69345849454b9c03991258aa1eff409472896e2b (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
/*
 *  linux/arch/m68k/mm/kmap.c
 *
 *  Copyright (C) 1997 Roman Hodek
 *
 *  10/01/99 cleaned up the code and changing to the same interface
 *	     used by other architectures		/Roman Zippel
 */

#include <linux/module.h>
#include <linux/mm.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>

#include <asm/setup.h>
#include <asm/segment.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
#include <asm/io.h>
#include <asm/system.h>

#undef DEBUG

#define PTRTREESIZE	(256*1024)

/*
 * For 040/060 we can use the virtual memory area like other architectures,
 * but for 020/030 we want to use early termination page descriptor and we
 * can't mix this with normal page descriptors, so we have to copy that code
 * (mm/vmalloc.c) and return appriorate aligned addresses.
 */

#ifdef CPU_M68040_OR_M68060_ONLY

#define IO_SIZE		PAGE_SIZE

static inline struct vm_struct *get_io_area(unsigned long size)
{
	return get_vm_area(size, VM_IOREMAP);
}


static inline void free_io_area(void *addr)
{
	vfree((void *)(PAGE_MASK & (unsigned long)addr));
}

#else

#define IO_SIZE		(256*1024)

static struct vm_struct *iolist;

static struct vm_struct *get_io_area(unsigned long size)
{
	unsigned long addr;
	struct vm_struct **p, *tmp, *area;

	area = kmalloc(sizeof(*area), GFP_KERNEL);
	if (!area)
		return NULL;
	addr = KMAP_START;
	for (p = &iolist; (tmp = *p) ; p = &tmp->next) {
		if (size + addr < (unsigned long)tmp->addr)
			break;
		if (addr > KMAP_END-size) {
			kfree(area);
			return NULL;
		}
		addr = tmp->size + (unsigned long)tmp->addr;
	}
	area->addr = (void *)addr;
	area->size = size + IO_SIZE;
	area->next = *p;
	*p = area;
	return area;
}

static inline void free_io_area(void *addr)
{
	struct vm_struct **p, *tmp;

	if (!addr)
		return;
	addr = (void *)((unsigned long)addr & -IO_SIZE);
	for (p = &iolist ; (tmp = *p) ; p = &tmp->next) {
		if (tmp->addr == addr) {
			*p = tmp->next;
			__iounmap(tmp->addr, tmp->size);
			kfree(tmp);
			return;
		}
	}
}

#endif

/*
 * Map some physical address range into the kernel address space.
 */
/* Rewritten by Andreas Schwab to remove all races. */

void __iomem *__ioremap(unsigned long physaddr, unsigned long size, int cacheflag)
{
	struct vm_struct *area;
	unsigned long virtaddr, retaddr;
	long offset;
	pgd_t *pgd_dir;
	pmd_t *pmd_dir;
	pte_t *pte_dir;

	/*
	 * Don't allow mappings that wrap..
	 */
	if (!size || physaddr > (unsigned long)(-size))
		return NULL;

#ifdef CONFIG_AMIGA
	if (MACH_IS_AMIGA) {
		if ((physaddr >= 0x40000000) && (physaddr + size < 0x60000000)
		    && (cacheflag == IOMAP_NOCACHE_SER))
			return (void __iomem *)physaddr;
	}
#endif

#ifdef DEBUG
	printk("ioremap: 0x%lx,0x%lx(%d) - ", physaddr, size, cacheflag);
#endif
	/*
	 * Mappings have to be aligned
	 */
	offset = physaddr & (IO_SIZE - 1);
	physaddr &= -IO_SIZE;
	size = (size + offset + IO_SIZE - 1) & -IO_SIZE;

	/*
	 * Ok, go for it..
	 */
	area = get_io_area(size);
	if (!area)
		return NULL;

	virtaddr = (unsigned long)area->addr;
	retaddr = virtaddr + offset;
#ifdef DEBUG
	printk("0x%lx,0x%lx,0x%lx", physaddr, virtaddr, retaddr);
#endif

	/*
	 * add cache and table flags to physical address
	 */
	if (CPU_IS_040_OR_060) {
		physaddr |= (_PAGE_PRESENT | _PAGE_GLOBAL040 |
			     _PAGE_ACCESSED | _PAGE_DIRTY);
		switch (cacheflag) {
		case IOMAP_FULL_CACHING:
			physaddr |= _PAGE_CACHE040;
			break;
		case IOMAP_NOCACHE_SER:
		default:
			physaddr |= _PAGE_NOCACHE_S;
			break;
		case IOMAP_NOCACHE_NONSER:
			physaddr |= _PAGE_NOCACHE;
			break;
		case IOMAP_WRITETHROUGH:
			physaddr |= _PAGE_CACHE040W;
			break;
		}
	} else {
		physaddr |= (_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_DIRTY);
		switch (cacheflag) {
		case IOMAP_NOCACHE_SER:
		case IOMAP_NOCACHE_NONSER:
		default:
			physaddr |= _PAGE_NOCACHE030;
			break;
		case IOMAP_FULL_CACHING:
		case IOMAP_WRITETHROUGH:
			break;
		}
	}

	while ((long)size > 0) {
#ifdef DEBUG
		if (!(virtaddr & (PTRTREESIZE-1)))
			printk ("\npa=%#lx va=%#lx ", physaddr, virtaddr);
#endif
		pgd_dir = pgd_offset_k(virtaddr);
		pmd_dir = pmd_alloc(&init_mm, pgd_dir, virtaddr);
		if (!pmd_dir) {
			printk("ioremap: no mem for pmd_dir\n");
			return NULL;
		}

		if (CPU_IS_020_OR_030) {
			pmd_dir->pmd[(virtaddr/PTRTREESIZE) & 15] = physaddr;
			physaddr += PTRTREESIZE;
			virtaddr += PTRTREESIZE;
			size -= PTRTREESIZE;
		} else {
			pte_dir = pte_alloc_kernel(pmd_dir, virtaddr);
			if (!pte_dir) {
				printk("ioremap: no mem for pte_dir\n");
				return NULL;
			}

			pte_val(*pte_dir) = physaddr;
			virtaddr += PAGE_SIZE;
			physaddr += PAGE_SIZE;
			size -= PAGE_SIZE;
		}
	}
#ifdef DEBUG
	printk("\n");
#endif
	flush_tlb_all();

	return (void __iomem *)retaddr;
}
EXPORT_SYMBOL(__ioremap);

/*
 * Unmap a ioremap()ed region again
 */
void iounmap(void __iomem *addr)
{
#ifdef CONFIG_AMIGA
	if ((!MACH_IS_AMIGA) ||
	    (((unsigned long)addr < 0x40000000) ||
	     ((unsigned long)addr > 0x60000000)))
			free_io_area((__force void *)addr);
#else
	free_io_area((__force void *)addr);
#endif
}
EXPORT_SYMBOL(iounmap);

/*
 * __iounmap unmaps nearly everything, so be careful
 * it doesn't free currently pointer/page tables anymore but it
 * wans't used anyway and might be added later.
 */
void __iounmap(void *addr, unsigned long size)
{
	unsigned long virtaddr = (unsigned long)addr;
	pgd_t *pgd_dir;
	pmd_t *pmd_dir;
	pte_t *pte_dir;

	while ((long)size > 0) {
		pgd_dir = pgd_offset_k(virtaddr);
		if (pgd_bad(*pgd_dir)) {
			printk("iounmap: bad pgd(%08lx)\n", pgd_val(*pgd_dir));
			pgd_clear(pgd_dir);
			return;
		}
		pmd_dir = pmd_offset(pgd_dir, virtaddr);

		if (CPU_IS_020_OR_030) {
			int pmd_off = (virtaddr/PTRTREESIZE) & 15;
			int pmd_type = pmd_dir->pmd[pmd_off] & _DESCTYPE_MASK;

			if (pmd_type == _PAGE_PRESENT) {
				pmd_dir->pmd[pmd_off] = 0;
				virtaddr += PTRTREESIZE;
				size -= PTRTREESIZE;
				continue;
			} else if (pmd_type == 0)
				continue;
		}

		if (pmd_bad(*pmd_dir)) {
			printk("iounmap: bad pmd (%08lx)\n", pmd_val(*pmd_dir));
			pmd_clear(pmd_dir);
			return;
		}
		pte_dir = pte_offset_kernel(pmd_dir, virtaddr);

		pte_val(*pte_dir) = 0;
		virtaddr += PAGE_SIZE;
		size -= PAGE_SIZE;
	}

	flush_tlb_all();
}

/*
 * Set new cache mode for some kernel address space.
 * The caller must push data for that range itself, if such data may already
 * be in the cache.
 */
void kernel_set_cachemode(void *addr, unsigned long size, int cmode)
{
	unsigned long virtaddr = (unsigned long)addr;
	pgd_t *pgd_dir;
	pmd_t *pmd_dir;
	pte_t *pte_dir;

	if (CPU_IS_040_OR_060) {
		switch (cmode) {
		case IOMAP_FULL_CACHING:
			cmode = _PAGE_CACHE040;
			break;
		case IOMAP_NOCACHE_SER:
		default:
			cmode = _PAGE_NOCACHE_S;
			break;
		case IOMAP_NOCACHE_NONSER:
			cmode = _PAGE_NOCACHE;
			break;
		case IOMAP_WRITETHROUGH:
			cmode = _PAGE_CACHE040W;
			break;
		}
	} else {
		switch (cmode) {
		case IOMAP_NOCACHE_SER:
		case IOMAP_NOCACHE_NONSER:
		default:
			cmode = _PAGE_NOCACHE030;
			break;
		case IOMAP_FULL_CACHING:
		case IOMAP_WRITETHROUGH:
			cmode = 0;
		}
	}

	while ((long)size > 0) {
		pgd_dir = pgd_offset_k(virtaddr);
		if (pgd_bad(*pgd_dir)) {
			printk("iocachemode: bad pgd(%08lx)\n", pgd_val(*pgd_dir));
			pgd_clear(pgd_dir);
			return;
		}
		pmd_dir = pmd_offset(pgd_dir, virtaddr);

		if (CPU_IS_020_OR_030) {
			int pmd_off = (virtaddr/PTRTREESIZE) & 15;

			if ((pmd_dir->pmd[pmd_off] & _DESCTYPE_MASK) == _PAGE_PRESENT) {
				pmd_dir->pmd[pmd_off] = (pmd_dir->pmd[pmd_off] &
							 _CACHEMASK040) | cmode;
				virtaddr += PTRTREESIZE;
				size -= PTRTREESIZE;
				continue;
			}
		}

		if (pmd_bad(*pmd_dir)) {
			printk("iocachemode: bad pmd (%08lx)\n", pmd_val(*pmd_dir));
			pmd_clear(pmd_dir);
			return;
		}
		pte_dir = pte_offset_kernel(pmd_dir, virtaddr);

		pte_val(*pte_dir) = (pte_val(*pte_dir) & _CACHEMASK040) | cmode;
		virtaddr += PAGE_SIZE;
		size -= PAGE_SIZE;
	}

	flush_tlb_all();
}
EXPORT_SYMBOL(kernel_set_cachemode);