xref: /linux/arch/m68k/sun3/sun3dvma.c (revision 14b42963f64b98ab61fa9723c03d71aa5ef4f862)
1 /*
2  * linux/arch/m68k/mm/sun3dvma.c
3  *
4  * Copyright (C) 2000 Sam Creasey
5  *
6  * Contains common routines for sun3/sun3x DVMA management.
7  */
8 
9 #include <linux/kernel.h>
10 #include <linux/mm.h>
11 #include <linux/list.h>
12 
13 #include <asm/page.h>
14 #include <asm/pgtable.h>
15 #include <asm/dvma.h>
16 
17 #undef DVMA_DEBUG
18 
19 #ifdef CONFIG_SUN3X
20 extern void dvma_unmap_iommu(unsigned long baddr, int len);
21 #else
22 static inline void dvma_unmap_iommu(unsigned long a, int b)
23 {
24 }
25 #endif
26 
27 #ifdef CONFIG_SUN3
28 extern void sun3_dvma_init(void);
29 #endif
30 
31 unsigned long iommu_use[IOMMU_TOTAL_ENTRIES];
32 
33 #define dvma_index(baddr) ((baddr - DVMA_START) >> DVMA_PAGE_SHIFT)
34 
35 #define dvma_entry_use(baddr)		(iommu_use[dvma_index(baddr)])
36 
37 struct hole {
38 	unsigned long start;
39 	unsigned long end;
40 	unsigned long size;
41 	struct list_head list;
42 };
43 
44 static struct list_head hole_list;
45 static struct list_head hole_cache;
46 static struct hole initholes[64];
47 
48 #ifdef DVMA_DEBUG
49 
50 static unsigned long dvma_allocs;
51 static unsigned long dvma_frees;
52 static unsigned long long dvma_alloc_bytes;
53 static unsigned long long dvma_free_bytes;
54 
55 static void print_use(void)
56 {
57 
58 	int i;
59 	int j = 0;
60 
61 	printk("dvma entry usage:\n");
62 
63 	for(i = 0; i < IOMMU_TOTAL_ENTRIES; i++) {
64 		if(!iommu_use[i])
65 			continue;
66 
67 		j++;
68 
69 		printk("dvma entry: %08lx len %08lx\n",
70 		       ( i << DVMA_PAGE_SHIFT) + DVMA_START,
71 		       iommu_use[i]);
72 	}
73 
74 	printk("%d entries in use total\n", j);
75 
76 	printk("allocation/free calls: %lu/%lu\n", dvma_allocs, dvma_frees);
77 	printk("allocation/free bytes: %Lx/%Lx\n", dvma_alloc_bytes,
78 	       dvma_free_bytes);
79 }
80 
81 static void print_holes(struct list_head *holes)
82 {
83 
84 	struct list_head *cur;
85 	struct hole *hole;
86 
87 	printk("listing dvma holes\n");
88 	list_for_each(cur, holes) {
89 		hole = list_entry(cur, struct hole, list);
90 
91 		if((hole->start == 0) && (hole->end == 0) && (hole->size == 0))
92 			continue;
93 
94 		printk("hole: start %08lx end %08lx size %08lx\n", hole->start, hole->end, hole->size);
95 	}
96 
97 	printk("end of hole listing...\n");
98 
99 }
100 #endif /* DVMA_DEBUG */
101 
102 static inline int refill(void)
103 {
104 
105 	struct hole *hole;
106 	struct hole *prev = NULL;
107 	struct list_head *cur;
108 	int ret = 0;
109 
110 	list_for_each(cur, &hole_list) {
111 		hole = list_entry(cur, struct hole, list);
112 
113 		if(!prev) {
114 			prev = hole;
115 			continue;
116 		}
117 
118 		if(hole->end == prev->start) {
119 			hole->size += prev->size;
120 			hole->end = prev->end;
121 			list_move(&(prev->list), &hole_cache);
122 			ret++;
123 		}
124 
125 	}
126 
127 	return ret;
128 }
129 
130 static inline struct hole *rmcache(void)
131 {
132 	struct hole *ret;
133 
134 	if(list_empty(&hole_cache)) {
135 		if(!refill()) {
136 			printk("out of dvma hole cache!\n");
137 			BUG();
138 		}
139 	}
140 
141 	ret = list_entry(hole_cache.next, struct hole, list);
142 	list_del(&(ret->list));
143 
144 	return ret;
145 
146 }
147 
148 static inline unsigned long get_baddr(int len, unsigned long align)
149 {
150 
151 	struct list_head *cur;
152 	struct hole *hole;
153 
154 	if(list_empty(&hole_list)) {
155 #ifdef DVMA_DEBUG
156 		printk("out of dvma holes! (printing hole cache)\n");
157 		print_holes(&hole_cache);
158 		print_use();
159 #endif
160 		BUG();
161 	}
162 
163 	list_for_each(cur, &hole_list) {
164 		unsigned long newlen;
165 
166 		hole = list_entry(cur, struct hole, list);
167 
168 		if(align > DVMA_PAGE_SIZE)
169 			newlen = len + ((hole->end - len) & (align-1));
170 		else
171 			newlen = len;
172 
173 		if(hole->size > newlen) {
174 			hole->end -= newlen;
175 			hole->size -= newlen;
176 			dvma_entry_use(hole->end) = newlen;
177 #ifdef DVMA_DEBUG
178 			dvma_allocs++;
179 			dvma_alloc_bytes += newlen;
180 #endif
181 			return hole->end;
182 		} else if(hole->size == newlen) {
183 			list_move(&(hole->list), &hole_cache);
184 			dvma_entry_use(hole->start) = newlen;
185 #ifdef DVMA_DEBUG
186 			dvma_allocs++;
187 			dvma_alloc_bytes += newlen;
188 #endif
189 			return hole->start;
190 		}
191 
192 	}
193 
194 	printk("unable to find dvma hole!\n");
195 	BUG();
196 	return 0;
197 }
198 
199 static inline int free_baddr(unsigned long baddr)
200 {
201 
202 	unsigned long len;
203 	struct hole *hole;
204 	struct list_head *cur;
205 	unsigned long orig_baddr;
206 
207 	orig_baddr = baddr;
208 	len = dvma_entry_use(baddr);
209 	dvma_entry_use(baddr) = 0;
210 	baddr &= DVMA_PAGE_MASK;
211 	dvma_unmap_iommu(baddr, len);
212 
213 #ifdef DVMA_DEBUG
214 	dvma_frees++;
215 	dvma_free_bytes += len;
216 #endif
217 
218 	list_for_each(cur, &hole_list) {
219 		hole = list_entry(cur, struct hole, list);
220 
221 		if(hole->end == baddr) {
222 			hole->end += len;
223 			hole->size += len;
224 			return 0;
225 		} else if(hole->start == (baddr + len)) {
226 			hole->start = baddr;
227 			hole->size += len;
228 			return 0;
229 		}
230 
231 	}
232 
233 	hole = rmcache();
234 
235 	hole->start = baddr;
236 	hole->end = baddr + len;
237 	hole->size = len;
238 
239 //	list_add_tail(&(hole->list), cur);
240 	list_add(&(hole->list), cur);
241 
242 	return 0;
243 
244 }
245 
246 void dvma_init(void)
247 {
248 
249 	struct hole *hole;
250 	int i;
251 
252 	INIT_LIST_HEAD(&hole_list);
253 	INIT_LIST_HEAD(&hole_cache);
254 
255 	/* prepare the hole cache */
256 	for(i = 0; i < 64; i++)
257 		list_add(&(initholes[i].list), &hole_cache);
258 
259 	hole = rmcache();
260 	hole->start = DVMA_START;
261 	hole->end = DVMA_END;
262 	hole->size = DVMA_SIZE;
263 
264 	list_add(&(hole->list), &hole_list);
265 
266 	memset(iommu_use, 0, sizeof(iommu_use));
267 
268 	dvma_unmap_iommu(DVMA_START, DVMA_SIZE);
269 
270 #ifdef CONFIG_SUN3
271 	sun3_dvma_init();
272 #endif
273 
274 }
275 
276 inline unsigned long dvma_map_align(unsigned long kaddr, int len, int align)
277 {
278 
279 	unsigned long baddr;
280 	unsigned long off;
281 
282 	if(!len)
283 		len = 0x800;
284 
285 	if(!kaddr || !len) {
286 //		printk("error: kaddr %lx len %x\n", kaddr, len);
287 //		*(int *)4 = 0;
288 		return 0;
289 	}
290 
291 #ifdef DEBUG
292 	printk("dvma_map request %08lx bytes from %08lx\n",
293 	       len, kaddr);
294 #endif
295 	off = kaddr & ~DVMA_PAGE_MASK;
296 	kaddr &= PAGE_MASK;
297 	len += off;
298 	len = ((len + (DVMA_PAGE_SIZE-1)) & DVMA_PAGE_MASK);
299 
300 	if(align == 0)
301 		align = DVMA_PAGE_SIZE;
302 	else
303 		align = ((align + (DVMA_PAGE_SIZE-1)) & DVMA_PAGE_MASK);
304 
305 	baddr = get_baddr(len, align);
306 //	printk("using baddr %lx\n", baddr);
307 
308 	if(!dvma_map_iommu(kaddr, baddr, len))
309 		return (baddr + off);
310 
311 	printk("dvma_map failed kaddr %lx baddr %lx len %x\n", kaddr, baddr, len);
312 	BUG();
313 	return 0;
314 }
315 
316 void dvma_unmap(void *baddr)
317 {
318 	unsigned long addr;
319 
320 	addr = (unsigned long)baddr;
321 	/* check if this is a vme mapping */
322 	if(!(addr & 0x00f00000))
323 		addr |= 0xf00000;
324 
325 	free_baddr(addr);
326 
327 	return;
328 
329 }
330 
331 
332 void *dvma_malloc_align(unsigned long len, unsigned long align)
333 {
334 	unsigned long kaddr;
335 	unsigned long baddr;
336 	unsigned long vaddr;
337 
338 	if(!len)
339 		return NULL;
340 
341 #ifdef DEBUG
342 	printk("dvma_malloc request %lx bytes\n", len);
343 #endif
344 	len = ((len + (DVMA_PAGE_SIZE-1)) & DVMA_PAGE_MASK);
345 
346         if((kaddr = __get_free_pages(GFP_ATOMIC, get_order(len))) == 0)
347 		return NULL;
348 
349 	if((baddr = (unsigned long)dvma_map_align(kaddr, len, align)) == 0) {
350 		free_pages(kaddr, get_order(len));
351 		return NULL;
352 	}
353 
354 	vaddr = dvma_btov(baddr);
355 
356 	if(dvma_map_cpu(kaddr, vaddr, len) < 0) {
357 		dvma_unmap((void *)baddr);
358 		free_pages(kaddr, get_order(len));
359 		return NULL;
360 	}
361 
362 #ifdef DEBUG
363 	printk("mapped %08lx bytes %08lx kern -> %08lx bus\n",
364 	       len, kaddr, baddr);
365 #endif
366 
367 	return (void *)vaddr;
368 
369 }
370 
371 void dvma_free(void *vaddr)
372 {
373 
374 	return;
375 
376 }
377