xref: /openbmc/linux/arch/m68k/sun3/sun3dvma.c (revision 63dc02bd)
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/gfp.h>
12 #include <linux/mm.h>
13 #include <linux/list.h>
14 
15 #include <asm/page.h>
16 #include <asm/pgtable.h>
17 #include <asm/dvma.h>
18 
19 #undef DVMA_DEBUG
20 
21 #ifdef CONFIG_SUN3X
22 extern void dvma_unmap_iommu(unsigned long baddr, int len);
23 #else
24 static inline void dvma_unmap_iommu(unsigned long a, int b)
25 {
26 }
27 #endif
28 
29 #ifdef CONFIG_SUN3
30 extern void sun3_dvma_init(void);
31 #endif
32 
33 static unsigned long iommu_use[IOMMU_TOTAL_ENTRIES];
34 
35 #define dvma_index(baddr) ((baddr - DVMA_START) >> DVMA_PAGE_SHIFT)
36 
37 #define dvma_entry_use(baddr)		(iommu_use[dvma_index(baddr)])
38 
39 struct hole {
40 	unsigned long start;
41 	unsigned long end;
42 	unsigned long size;
43 	struct list_head list;
44 };
45 
46 static struct list_head hole_list;
47 static struct list_head hole_cache;
48 static struct hole initholes[64];
49 
50 #ifdef DVMA_DEBUG
51 
52 static unsigned long dvma_allocs;
53 static unsigned long dvma_frees;
54 static unsigned long long dvma_alloc_bytes;
55 static unsigned long long dvma_free_bytes;
56 
57 static void print_use(void)
58 {
59 
60 	int i;
61 	int j = 0;
62 
63 	printk("dvma entry usage:\n");
64 
65 	for(i = 0; i < IOMMU_TOTAL_ENTRIES; i++) {
66 		if(!iommu_use[i])
67 			continue;
68 
69 		j++;
70 
71 		printk("dvma entry: %08lx len %08lx\n",
72 		       ( i << DVMA_PAGE_SHIFT) + DVMA_START,
73 		       iommu_use[i]);
74 	}
75 
76 	printk("%d entries in use total\n", j);
77 
78 	printk("allocation/free calls: %lu/%lu\n", dvma_allocs, dvma_frees);
79 	printk("allocation/free bytes: %Lx/%Lx\n", dvma_alloc_bytes,
80 	       dvma_free_bytes);
81 }
82 
83 static void print_holes(struct list_head *holes)
84 {
85 
86 	struct list_head *cur;
87 	struct hole *hole;
88 
89 	printk("listing dvma holes\n");
90 	list_for_each(cur, holes) {
91 		hole = list_entry(cur, struct hole, list);
92 
93 		if((hole->start == 0) && (hole->end == 0) && (hole->size == 0))
94 			continue;
95 
96 		printk("hole: start %08lx end %08lx size %08lx\n", hole->start, hole->end, hole->size);
97 	}
98 
99 	printk("end of hole listing...\n");
100 
101 }
102 #endif /* DVMA_DEBUG */
103 
104 static inline int refill(void)
105 {
106 
107 	struct hole *hole;
108 	struct hole *prev = NULL;
109 	struct list_head *cur;
110 	int ret = 0;
111 
112 	list_for_each(cur, &hole_list) {
113 		hole = list_entry(cur, struct hole, list);
114 
115 		if(!prev) {
116 			prev = hole;
117 			continue;
118 		}
119 
120 		if(hole->end == prev->start) {
121 			hole->size += prev->size;
122 			hole->end = prev->end;
123 			list_move(&(prev->list), &hole_cache);
124 			ret++;
125 		}
126 
127 	}
128 
129 	return ret;
130 }
131 
132 static inline struct hole *rmcache(void)
133 {
134 	struct hole *ret;
135 
136 	if(list_empty(&hole_cache)) {
137 		if(!refill()) {
138 			printk("out of dvma hole cache!\n");
139 			BUG();
140 		}
141 	}
142 
143 	ret = list_entry(hole_cache.next, struct hole, list);
144 	list_del(&(ret->list));
145 
146 	return ret;
147 
148 }
149 
150 static inline unsigned long get_baddr(int len, unsigned long align)
151 {
152 
153 	struct list_head *cur;
154 	struct hole *hole;
155 
156 	if(list_empty(&hole_list)) {
157 #ifdef DVMA_DEBUG
158 		printk("out of dvma holes! (printing hole cache)\n");
159 		print_holes(&hole_cache);
160 		print_use();
161 #endif
162 		BUG();
163 	}
164 
165 	list_for_each(cur, &hole_list) {
166 		unsigned long newlen;
167 
168 		hole = list_entry(cur, struct hole, list);
169 
170 		if(align > DVMA_PAGE_SIZE)
171 			newlen = len + ((hole->end - len) & (align-1));
172 		else
173 			newlen = len;
174 
175 		if(hole->size > newlen) {
176 			hole->end -= newlen;
177 			hole->size -= newlen;
178 			dvma_entry_use(hole->end) = newlen;
179 #ifdef DVMA_DEBUG
180 			dvma_allocs++;
181 			dvma_alloc_bytes += newlen;
182 #endif
183 			return hole->end;
184 		} else if(hole->size == newlen) {
185 			list_move(&(hole->list), &hole_cache);
186 			dvma_entry_use(hole->start) = newlen;
187 #ifdef DVMA_DEBUG
188 			dvma_allocs++;
189 			dvma_alloc_bytes += newlen;
190 #endif
191 			return hole->start;
192 		}
193 
194 	}
195 
196 	printk("unable to find dvma hole!\n");
197 	BUG();
198 	return 0;
199 }
200 
201 static inline int free_baddr(unsigned long baddr)
202 {
203 
204 	unsigned long len;
205 	struct hole *hole;
206 	struct list_head *cur;
207 	unsigned long orig_baddr;
208 
209 	orig_baddr = baddr;
210 	len = dvma_entry_use(baddr);
211 	dvma_entry_use(baddr) = 0;
212 	baddr &= DVMA_PAGE_MASK;
213 	dvma_unmap_iommu(baddr, len);
214 
215 #ifdef DVMA_DEBUG
216 	dvma_frees++;
217 	dvma_free_bytes += len;
218 #endif
219 
220 	list_for_each(cur, &hole_list) {
221 		hole = list_entry(cur, struct hole, list);
222 
223 		if(hole->end == baddr) {
224 			hole->end += len;
225 			hole->size += len;
226 			return 0;
227 		} else if(hole->start == (baddr + len)) {
228 			hole->start = baddr;
229 			hole->size += len;
230 			return 0;
231 		}
232 
233 	}
234 
235 	hole = rmcache();
236 
237 	hole->start = baddr;
238 	hole->end = baddr + len;
239 	hole->size = len;
240 
241 //	list_add_tail(&(hole->list), cur);
242 	list_add(&(hole->list), cur);
243 
244 	return 0;
245 
246 }
247 
248 void dvma_init(void)
249 {
250 
251 	struct hole *hole;
252 	int i;
253 
254 	INIT_LIST_HEAD(&hole_list);
255 	INIT_LIST_HEAD(&hole_cache);
256 
257 	/* prepare the hole cache */
258 	for(i = 0; i < 64; i++)
259 		list_add(&(initholes[i].list), &hole_cache);
260 
261 	hole = rmcache();
262 	hole->start = DVMA_START;
263 	hole->end = DVMA_END;
264 	hole->size = DVMA_SIZE;
265 
266 	list_add(&(hole->list), &hole_list);
267 
268 	memset(iommu_use, 0, sizeof(iommu_use));
269 
270 	dvma_unmap_iommu(DVMA_START, DVMA_SIZE);
271 
272 #ifdef CONFIG_SUN3
273 	sun3_dvma_init();
274 #endif
275 
276 }
277 
278 inline unsigned long dvma_map_align(unsigned long kaddr, int len, int align)
279 {
280 
281 	unsigned long baddr;
282 	unsigned long off;
283 
284 	if(!len)
285 		len = 0x800;
286 
287 	if(!kaddr || !len) {
288 //		printk("error: kaddr %lx len %x\n", kaddr, len);
289 //		*(int *)4 = 0;
290 		return 0;
291 	}
292 
293 #ifdef DEBUG
294 	printk("dvma_map request %08lx bytes from %08lx\n",
295 	       len, kaddr);
296 #endif
297 	off = kaddr & ~DVMA_PAGE_MASK;
298 	kaddr &= PAGE_MASK;
299 	len += off;
300 	len = ((len + (DVMA_PAGE_SIZE-1)) & DVMA_PAGE_MASK);
301 
302 	if(align == 0)
303 		align = DVMA_PAGE_SIZE;
304 	else
305 		align = ((align + (DVMA_PAGE_SIZE-1)) & DVMA_PAGE_MASK);
306 
307 	baddr = get_baddr(len, align);
308 //	printk("using baddr %lx\n", baddr);
309 
310 	if(!dvma_map_iommu(kaddr, baddr, len))
311 		return (baddr + off);
312 
313 	printk("dvma_map failed kaddr %lx baddr %lx len %x\n", kaddr, baddr, len);
314 	BUG();
315 	return 0;
316 }
317 EXPORT_SYMBOL(dvma_map_align);
318 
319 void dvma_unmap(void *baddr)
320 {
321 	unsigned long addr;
322 
323 	addr = (unsigned long)baddr;
324 	/* check if this is a vme mapping */
325 	if(!(addr & 0x00f00000))
326 		addr |= 0xf00000;
327 
328 	free_baddr(addr);
329 
330 	return;
331 
332 }
333 EXPORT_SYMBOL(dvma_unmap);
334 
335 void *dvma_malloc_align(unsigned long len, unsigned long align)
336 {
337 	unsigned long kaddr;
338 	unsigned long baddr;
339 	unsigned long vaddr;
340 
341 	if(!len)
342 		return NULL;
343 
344 #ifdef DEBUG
345 	printk("dvma_malloc request %lx bytes\n", len);
346 #endif
347 	len = ((len + (DVMA_PAGE_SIZE-1)) & DVMA_PAGE_MASK);
348 
349         if((kaddr = __get_free_pages(GFP_ATOMIC, get_order(len))) == 0)
350 		return NULL;
351 
352 	if((baddr = (unsigned long)dvma_map_align(kaddr, len, align)) == 0) {
353 		free_pages(kaddr, get_order(len));
354 		return NULL;
355 	}
356 
357 	vaddr = dvma_btov(baddr);
358 
359 	if(dvma_map_cpu(kaddr, vaddr, len) < 0) {
360 		dvma_unmap((void *)baddr);
361 		free_pages(kaddr, get_order(len));
362 		return NULL;
363 	}
364 
365 #ifdef DEBUG
366 	printk("mapped %08lx bytes %08lx kern -> %08lx bus\n",
367 	       len, kaddr, baddr);
368 #endif
369 
370 	return (void *)vaddr;
371 
372 }
373 EXPORT_SYMBOL(dvma_malloc_align);
374 
375 void dvma_free(void *vaddr)
376 {
377 
378 	return;
379 
380 }
381 EXPORT_SYMBOL(dvma_free);
382