xref: /openbmc/linux/arch/m68k/sun3/sun3dvma.c (revision 1da177e4)
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/config.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 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_del(&(prev->list));
123 			list_add(&(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_del(&(hole->list));
186 			list_add(&(hole->list), &hole_cache);
187 			dvma_entry_use(hole->start) = newlen;
188 #ifdef DVMA_DEBUG
189 			dvma_allocs++;
190 			dvma_alloc_bytes += newlen;
191 #endif
192 			return hole->start;
193 		}
194 
195 	}
196 
197 	printk("unable to find dvma hole!\n");
198 	BUG();
199 	return 0;
200 }
201 
202 static inline int free_baddr(unsigned long baddr)
203 {
204 
205 	unsigned long len;
206 	struct hole *hole;
207 	struct list_head *cur;
208 	unsigned long orig_baddr;
209 
210 	orig_baddr = baddr;
211 	len = dvma_entry_use(baddr);
212 	dvma_entry_use(baddr) = 0;
213 	baddr &= DVMA_PAGE_MASK;
214 	dvma_unmap_iommu(baddr, len);
215 
216 #ifdef DVMA_DEBUG
217 	dvma_frees++;
218 	dvma_free_bytes += len;
219 #endif
220 
221 	list_for_each(cur, &hole_list) {
222 		hole = list_entry(cur, struct hole, list);
223 
224 		if(hole->end == baddr) {
225 			hole->end += len;
226 			hole->size += len;
227 			return 0;
228 		} else if(hole->start == (baddr + len)) {
229 			hole->start = baddr;
230 			hole->size += len;
231 			return 0;
232 		}
233 
234 	}
235 
236 	hole = rmcache();
237 
238 	hole->start = baddr;
239 	hole->end = baddr + len;
240 	hole->size = len;
241 
242 //	list_add_tail(&(hole->list), cur);
243 	list_add(&(hole->list), cur);
244 
245 	return 0;
246 
247 }
248 
249 void dvma_init(void)
250 {
251 
252 	struct hole *hole;
253 	int i;
254 
255 	INIT_LIST_HEAD(&hole_list);
256 	INIT_LIST_HEAD(&hole_cache);
257 
258 	/* prepare the hole cache */
259 	for(i = 0; i < 64; i++)
260 		list_add(&(initholes[i].list), &hole_cache);
261 
262 	hole = rmcache();
263 	hole->start = DVMA_START;
264 	hole->end = DVMA_END;
265 	hole->size = DVMA_SIZE;
266 
267 	list_add(&(hole->list), &hole_list);
268 
269 	memset(iommu_use, 0, sizeof(iommu_use));
270 
271 	dvma_unmap_iommu(DVMA_START, DVMA_SIZE);
272 
273 #ifdef CONFIG_SUN3
274 	sun3_dvma_init();
275 #endif
276 
277 }
278 
279 inline unsigned long dvma_map_align(unsigned long kaddr, int len, int align)
280 {
281 
282 	unsigned long baddr;
283 	unsigned long off;
284 
285 	if(!len)
286 		len = 0x800;
287 
288 	if(!kaddr || !len) {
289 //		printk("error: kaddr %lx len %x\n", kaddr, len);
290 //		*(int *)4 = 0;
291 		return 0;
292 	}
293 
294 #ifdef DEBUG
295 	printk("dvma_map request %08lx bytes from %08lx\n",
296 	       len, kaddr);
297 #endif
298 	off = kaddr & ~DVMA_PAGE_MASK;
299 	kaddr &= PAGE_MASK;
300 	len += off;
301 	len = ((len + (DVMA_PAGE_SIZE-1)) & DVMA_PAGE_MASK);
302 
303 	if(align == 0)
304 		align = DVMA_PAGE_SIZE;
305 	else
306 		align = ((align + (DVMA_PAGE_SIZE-1)) & DVMA_PAGE_MASK);
307 
308 	baddr = get_baddr(len, align);
309 //	printk("using baddr %lx\n", baddr);
310 
311 	if(!dvma_map_iommu(kaddr, baddr, len))
312 		return (baddr + off);
313 
314 	printk("dvma_map failed kaddr %lx baddr %lx len %x\n", kaddr, baddr, len);
315 	BUG();
316 	return 0;
317 }
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 
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 
374 void dvma_free(void *vaddr)
375 {
376 
377 	return;
378 
379 }
380