xref: /openbmc/linux/arch/m68k/sun3/sun3dvma.c (revision fd589a8f)
1 /*
2  * linux/arch/m68k/sun3/sun3dvma.c
3  *
4  * Copyright (C) 2000 Sam Creasey
5  *
6  * Contains common routines for sun3/sun3x DVMA management.
7  */
8 
9 #include <linux/module.h>
10 #include <linux/kernel.h>
11 #include <linux/mm.h>
12 #include <linux/list.h>
13 
14 #include <asm/page.h>
15 #include <asm/pgtable.h>
16 #include <asm/dvma.h>
17 
18 #undef DVMA_DEBUG
19 
20 #ifdef CONFIG_SUN3X
21 extern void dvma_unmap_iommu(unsigned long baddr, int len);
22 #else
23 static inline void dvma_unmap_iommu(unsigned long a, int b)
24 {
25 }
26 #endif
27 
28 #ifdef CONFIG_SUN3
29 extern void sun3_dvma_init(void);
30 #endif
31 
32 static unsigned long iommu_use[IOMMU_TOTAL_ENTRIES];
33 
34 #define dvma_index(baddr) ((baddr - DVMA_START) >> DVMA_PAGE_SHIFT)
35 
36 #define dvma_entry_use(baddr)		(iommu_use[dvma_index(baddr)])
37 
38 struct hole {
39 	unsigned long start;
40 	unsigned long end;
41 	unsigned long size;
42 	struct list_head list;
43 };
44 
45 static struct list_head hole_list;
46 static struct list_head hole_cache;
47 static struct hole initholes[64];
48 
49 #ifdef DVMA_DEBUG
50 
51 static unsigned long dvma_allocs;
52 static unsigned long dvma_frees;
53 static unsigned long long dvma_alloc_bytes;
54 static unsigned long long dvma_free_bytes;
55 
56 static void print_use(void)
57 {
58 
59 	int i;
60 	int j = 0;
61 
62 	printk("dvma entry usage:\n");
63 
64 	for(i = 0; i < IOMMU_TOTAL_ENTRIES; i++) {
65 		if(!iommu_use[i])
66 			continue;
67 
68 		j++;
69 
70 		printk("dvma entry: %08lx len %08lx\n",
71 		       ( i << DVMA_PAGE_SHIFT) + DVMA_START,
72 		       iommu_use[i]);
73 	}
74 
75 	printk("%d entries in use total\n", j);
76 
77 	printk("allocation/free calls: %lu/%lu\n", dvma_allocs, dvma_frees);
78 	printk("allocation/free bytes: %Lx/%Lx\n", dvma_alloc_bytes,
79 	       dvma_free_bytes);
80 }
81 
82 static void print_holes(struct list_head *holes)
83 {
84 
85 	struct list_head *cur;
86 	struct hole *hole;
87 
88 	printk("listing dvma holes\n");
89 	list_for_each(cur, holes) {
90 		hole = list_entry(cur, struct hole, list);
91 
92 		if((hole->start == 0) && (hole->end == 0) && (hole->size == 0))
93 			continue;
94 
95 		printk("hole: start %08lx end %08lx size %08lx\n", hole->start, hole->end, hole->size);
96 	}
97 
98 	printk("end of hole listing...\n");
99 
100 }
101 #endif /* DVMA_DEBUG */
102 
103 static inline int refill(void)
104 {
105 
106 	struct hole *hole;
107 	struct hole *prev = NULL;
108 	struct list_head *cur;
109 	int ret = 0;
110 
111 	list_for_each(cur, &hole_list) {
112 		hole = list_entry(cur, struct hole, list);
113 
114 		if(!prev) {
115 			prev = hole;
116 			continue;
117 		}
118 
119 		if(hole->end == prev->start) {
120 			hole->size += prev->size;
121 			hole->end = prev->end;
122 			list_move(&(prev->list), &hole_cache);
123 			ret++;
124 		}
125 
126 	}
127 
128 	return ret;
129 }
130 
131 static inline struct hole *rmcache(void)
132 {
133 	struct hole *ret;
134 
135 	if(list_empty(&hole_cache)) {
136 		if(!refill()) {
137 			printk("out of dvma hole cache!\n");
138 			BUG();
139 		}
140 	}
141 
142 	ret = list_entry(hole_cache.next, struct hole, list);
143 	list_del(&(ret->list));
144 
145 	return ret;
146 
147 }
148 
149 static inline unsigned long get_baddr(int len, unsigned long align)
150 {
151 
152 	struct list_head *cur;
153 	struct hole *hole;
154 
155 	if(list_empty(&hole_list)) {
156 #ifdef DVMA_DEBUG
157 		printk("out of dvma holes! (printing hole cache)\n");
158 		print_holes(&hole_cache);
159 		print_use();
160 #endif
161 		BUG();
162 	}
163 
164 	list_for_each(cur, &hole_list) {
165 		unsigned long newlen;
166 
167 		hole = list_entry(cur, struct hole, list);
168 
169 		if(align > DVMA_PAGE_SIZE)
170 			newlen = len + ((hole->end - len) & (align-1));
171 		else
172 			newlen = len;
173 
174 		if(hole->size > newlen) {
175 			hole->end -= newlen;
176 			hole->size -= newlen;
177 			dvma_entry_use(hole->end) = newlen;
178 #ifdef DVMA_DEBUG
179 			dvma_allocs++;
180 			dvma_alloc_bytes += newlen;
181 #endif
182 			return hole->end;
183 		} else if(hole->size == newlen) {
184 			list_move(&(hole->list), &hole_cache);
185 			dvma_entry_use(hole->start) = newlen;
186 #ifdef DVMA_DEBUG
187 			dvma_allocs++;
188 			dvma_alloc_bytes += newlen;
189 #endif
190 			return hole->start;
191 		}
192 
193 	}
194 
195 	printk("unable to find dvma hole!\n");
196 	BUG();
197 	return 0;
198 }
199 
200 static inline int free_baddr(unsigned long baddr)
201 {
202 
203 	unsigned long len;
204 	struct hole *hole;
205 	struct list_head *cur;
206 	unsigned long orig_baddr;
207 
208 	orig_baddr = baddr;
209 	len = dvma_entry_use(baddr);
210 	dvma_entry_use(baddr) = 0;
211 	baddr &= DVMA_PAGE_MASK;
212 	dvma_unmap_iommu(baddr, len);
213 
214 #ifdef DVMA_DEBUG
215 	dvma_frees++;
216 	dvma_free_bytes += len;
217 #endif
218 
219 	list_for_each(cur, &hole_list) {
220 		hole = list_entry(cur, struct hole, list);
221 
222 		if(hole->end == baddr) {
223 			hole->end += len;
224 			hole->size += len;
225 			return 0;
226 		} else if(hole->start == (baddr + len)) {
227 			hole->start = baddr;
228 			hole->size += len;
229 			return 0;
230 		}
231 
232 	}
233 
234 	hole = rmcache();
235 
236 	hole->start = baddr;
237 	hole->end = baddr + len;
238 	hole->size = len;
239 
240 //	list_add_tail(&(hole->list), cur);
241 	list_add(&(hole->list), cur);
242 
243 	return 0;
244 
245 }
246 
247 void dvma_init(void)
248 {
249 
250 	struct hole *hole;
251 	int i;
252 
253 	INIT_LIST_HEAD(&hole_list);
254 	INIT_LIST_HEAD(&hole_cache);
255 
256 	/* prepare the hole cache */
257 	for(i = 0; i < 64; i++)
258 		list_add(&(initholes[i].list), &hole_cache);
259 
260 	hole = rmcache();
261 	hole->start = DVMA_START;
262 	hole->end = DVMA_END;
263 	hole->size = DVMA_SIZE;
264 
265 	list_add(&(hole->list), &hole_list);
266 
267 	memset(iommu_use, 0, sizeof(iommu_use));
268 
269 	dvma_unmap_iommu(DVMA_START, DVMA_SIZE);
270 
271 #ifdef CONFIG_SUN3
272 	sun3_dvma_init();
273 #endif
274 
275 }
276 
277 inline unsigned long dvma_map_align(unsigned long kaddr, int len, int align)
278 {
279 
280 	unsigned long baddr;
281 	unsigned long off;
282 
283 	if(!len)
284 		len = 0x800;
285 
286 	if(!kaddr || !len) {
287 //		printk("error: kaddr %lx len %x\n", kaddr, len);
288 //		*(int *)4 = 0;
289 		return 0;
290 	}
291 
292 #ifdef DEBUG
293 	printk("dvma_map request %08lx bytes from %08lx\n",
294 	       len, kaddr);
295 #endif
296 	off = kaddr & ~DVMA_PAGE_MASK;
297 	kaddr &= PAGE_MASK;
298 	len += off;
299 	len = ((len + (DVMA_PAGE_SIZE-1)) & DVMA_PAGE_MASK);
300 
301 	if(align == 0)
302 		align = DVMA_PAGE_SIZE;
303 	else
304 		align = ((align + (DVMA_PAGE_SIZE-1)) & DVMA_PAGE_MASK);
305 
306 	baddr = get_baddr(len, align);
307 //	printk("using baddr %lx\n", baddr);
308 
309 	if(!dvma_map_iommu(kaddr, baddr, len))
310 		return (baddr + off);
311 
312 	printk("dvma_map failed kaddr %lx baddr %lx len %x\n", kaddr, baddr, len);
313 	BUG();
314 	return 0;
315 }
316 EXPORT_SYMBOL(dvma_map_align);
317 
318 void dvma_unmap(void *baddr)
319 {
320 	unsigned long addr;
321 
322 	addr = (unsigned long)baddr;
323 	/* check if this is a vme mapping */
324 	if(!(addr & 0x00f00000))
325 		addr |= 0xf00000;
326 
327 	free_baddr(addr);
328 
329 	return;
330 
331 }
332 EXPORT_SYMBOL(dvma_unmap);
333 
334 void *dvma_malloc_align(unsigned long len, unsigned long align)
335 {
336 	unsigned long kaddr;
337 	unsigned long baddr;
338 	unsigned long vaddr;
339 
340 	if(!len)
341 		return NULL;
342 
343 #ifdef DEBUG
344 	printk("dvma_malloc request %lx bytes\n", len);
345 #endif
346 	len = ((len + (DVMA_PAGE_SIZE-1)) & DVMA_PAGE_MASK);
347 
348         if((kaddr = __get_free_pages(GFP_ATOMIC, get_order(len))) == 0)
349 		return NULL;
350 
351 	if((baddr = (unsigned long)dvma_map_align(kaddr, len, align)) == 0) {
352 		free_pages(kaddr, get_order(len));
353 		return NULL;
354 	}
355 
356 	vaddr = dvma_btov(baddr);
357 
358 	if(dvma_map_cpu(kaddr, vaddr, len) < 0) {
359 		dvma_unmap((void *)baddr);
360 		free_pages(kaddr, get_order(len));
361 		return NULL;
362 	}
363 
364 #ifdef DEBUG
365 	printk("mapped %08lx bytes %08lx kern -> %08lx bus\n",
366 	       len, kaddr, baddr);
367 #endif
368 
369 	return (void *)vaddr;
370 
371 }
372 EXPORT_SYMBOL(dvma_malloc_align);
373 
374 void dvma_free(void *vaddr)
375 {
376 
377 	return;
378 
379 }
380 EXPORT_SYMBOL(dvma_free);
381