xref: /openbmc/linux/arch/m68k/sun3/sun3dvma.c (revision eb3fcf00)
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/bootmem.h>
10 #include <linux/init.h>
11 #include <linux/module.h>
12 #include <linux/kernel.h>
13 #include <linux/gfp.h>
14 #include <linux/mm.h>
15 #include <linux/list.h>
16 
17 #include <asm/page.h>
18 #include <asm/pgtable.h>
19 #include <asm/dvma.h>
20 
21 #undef DVMA_DEBUG
22 
23 #ifdef CONFIG_SUN3X
24 extern void dvma_unmap_iommu(unsigned long baddr, int len);
25 #else
26 static inline void dvma_unmap_iommu(unsigned long a, int b)
27 {
28 }
29 #endif
30 
31 #ifdef CONFIG_SUN3
32 extern void sun3_dvma_init(void);
33 #endif
34 
35 static unsigned long *iommu_use;
36 
37 #define dvma_index(baddr) ((baddr - DVMA_START) >> DVMA_PAGE_SHIFT)
38 
39 #define dvma_entry_use(baddr)		(iommu_use[dvma_index(baddr)])
40 
41 struct hole {
42 	unsigned long start;
43 	unsigned long end;
44 	unsigned long size;
45 	struct list_head list;
46 };
47 
48 static struct list_head hole_list;
49 static struct list_head hole_cache;
50 static struct hole initholes[64];
51 
52 #ifdef DVMA_DEBUG
53 
54 static unsigned long dvma_allocs;
55 static unsigned long dvma_frees;
56 static unsigned long long dvma_alloc_bytes;
57 static unsigned long long dvma_free_bytes;
58 
59 static void print_use(void)
60 {
61 
62 	int i;
63 	int j = 0;
64 
65 	printk("dvma entry usage:\n");
66 
67 	for(i = 0; i < IOMMU_TOTAL_ENTRIES; i++) {
68 		if(!iommu_use[i])
69 			continue;
70 
71 		j++;
72 
73 		printk("dvma entry: %08lx len %08lx\n",
74 		       ( i << DVMA_PAGE_SHIFT) + DVMA_START,
75 		       iommu_use[i]);
76 	}
77 
78 	printk("%d entries in use total\n", j);
79 
80 	printk("allocation/free calls: %lu/%lu\n", dvma_allocs, dvma_frees);
81 	printk("allocation/free bytes: %Lx/%Lx\n", dvma_alloc_bytes,
82 	       dvma_free_bytes);
83 }
84 
85 static void print_holes(struct list_head *holes)
86 {
87 
88 	struct list_head *cur;
89 	struct hole *hole;
90 
91 	printk("listing dvma holes\n");
92 	list_for_each(cur, holes) {
93 		hole = list_entry(cur, struct hole, list);
94 
95 		if((hole->start == 0) && (hole->end == 0) && (hole->size == 0))
96 			continue;
97 
98 		printk("hole: start %08lx end %08lx size %08lx\n", hole->start, hole->end, hole->size);
99 	}
100 
101 	printk("end of hole listing...\n");
102 
103 }
104 #endif /* DVMA_DEBUG */
105 
106 static inline int refill(void)
107 {
108 
109 	struct hole *hole;
110 	struct hole *prev = NULL;
111 	struct list_head *cur;
112 	int ret = 0;
113 
114 	list_for_each(cur, &hole_list) {
115 		hole = list_entry(cur, struct hole, list);
116 
117 		if(!prev) {
118 			prev = hole;
119 			continue;
120 		}
121 
122 		if(hole->end == prev->start) {
123 			hole->size += prev->size;
124 			hole->end = prev->end;
125 			list_move(&(prev->list), &hole_cache);
126 			ret++;
127 		}
128 
129 	}
130 
131 	return ret;
132 }
133 
134 static inline struct hole *rmcache(void)
135 {
136 	struct hole *ret;
137 
138 	if(list_empty(&hole_cache)) {
139 		if(!refill()) {
140 			printk("out of dvma hole cache!\n");
141 			BUG();
142 		}
143 	}
144 
145 	ret = list_entry(hole_cache.next, struct hole, list);
146 	list_del(&(ret->list));
147 
148 	return ret;
149 
150 }
151 
152 static inline unsigned long get_baddr(int len, unsigned long align)
153 {
154 
155 	struct list_head *cur;
156 	struct hole *hole;
157 
158 	if(list_empty(&hole_list)) {
159 #ifdef DVMA_DEBUG
160 		printk("out of dvma holes! (printing hole cache)\n");
161 		print_holes(&hole_cache);
162 		print_use();
163 #endif
164 		BUG();
165 	}
166 
167 	list_for_each(cur, &hole_list) {
168 		unsigned long newlen;
169 
170 		hole = list_entry(cur, struct hole, list);
171 
172 		if(align > DVMA_PAGE_SIZE)
173 			newlen = len + ((hole->end - len) & (align-1));
174 		else
175 			newlen = len;
176 
177 		if(hole->size > newlen) {
178 			hole->end -= newlen;
179 			hole->size -= newlen;
180 			dvma_entry_use(hole->end) = newlen;
181 #ifdef DVMA_DEBUG
182 			dvma_allocs++;
183 			dvma_alloc_bytes += newlen;
184 #endif
185 			return hole->end;
186 		} else if(hole->size == newlen) {
187 			list_move(&(hole->list), &hole_cache);
188 			dvma_entry_use(hole->start) = newlen;
189 #ifdef DVMA_DEBUG
190 			dvma_allocs++;
191 			dvma_alloc_bytes += newlen;
192 #endif
193 			return hole->start;
194 		}
195 
196 	}
197 
198 	printk("unable to find dvma hole!\n");
199 	BUG();
200 	return 0;
201 }
202 
203 static inline int free_baddr(unsigned long baddr)
204 {
205 
206 	unsigned long len;
207 	struct hole *hole;
208 	struct list_head *cur;
209 	unsigned long orig_baddr;
210 
211 	orig_baddr = baddr;
212 	len = dvma_entry_use(baddr);
213 	dvma_entry_use(baddr) = 0;
214 	baddr &= DVMA_PAGE_MASK;
215 	dvma_unmap_iommu(baddr, len);
216 
217 #ifdef DVMA_DEBUG
218 	dvma_frees++;
219 	dvma_free_bytes += len;
220 #endif
221 
222 	list_for_each(cur, &hole_list) {
223 		hole = list_entry(cur, struct hole, list);
224 
225 		if(hole->end == baddr) {
226 			hole->end += len;
227 			hole->size += len;
228 			return 0;
229 		} else if(hole->start == (baddr + len)) {
230 			hole->start = baddr;
231 			hole->size += len;
232 			return 0;
233 		}
234 
235 	}
236 
237 	hole = rmcache();
238 
239 	hole->start = baddr;
240 	hole->end = baddr + len;
241 	hole->size = len;
242 
243 //	list_add_tail(&(hole->list), cur);
244 	list_add(&(hole->list), cur);
245 
246 	return 0;
247 
248 }
249 
250 void __init dvma_init(void)
251 {
252 
253 	struct hole *hole;
254 	int i;
255 
256 	INIT_LIST_HEAD(&hole_list);
257 	INIT_LIST_HEAD(&hole_cache);
258 
259 	/* prepare the hole cache */
260 	for(i = 0; i < 64; i++)
261 		list_add(&(initholes[i].list), &hole_cache);
262 
263 	hole = rmcache();
264 	hole->start = DVMA_START;
265 	hole->end = DVMA_END;
266 	hole->size = DVMA_SIZE;
267 
268 	list_add(&(hole->list), &hole_list);
269 
270 	iommu_use = alloc_bootmem(IOMMU_TOTAL_ENTRIES * sizeof(unsigned long));
271 
272 	dvma_unmap_iommu(DVMA_START, DVMA_SIZE);
273 
274 #ifdef CONFIG_SUN3
275 	sun3_dvma_init();
276 #endif
277 
278 }
279 
280 unsigned long dvma_map_align(unsigned long kaddr, int len, int align)
281 {
282 
283 	unsigned long baddr;
284 	unsigned long off;
285 
286 	if(!len)
287 		len = 0x800;
288 
289 	if(!kaddr || !len) {
290 //		printk("error: kaddr %lx len %x\n", kaddr, len);
291 //		*(int *)4 = 0;
292 		return 0;
293 	}
294 
295 #ifdef DEBUG
296 	printk("dvma_map request %08lx bytes from %08lx\n",
297 	       len, kaddr);
298 #endif
299 	off = kaddr & ~DVMA_PAGE_MASK;
300 	kaddr &= PAGE_MASK;
301 	len += off;
302 	len = ((len + (DVMA_PAGE_SIZE-1)) & DVMA_PAGE_MASK);
303 
304 	if(align == 0)
305 		align = DVMA_PAGE_SIZE;
306 	else
307 		align = ((align + (DVMA_PAGE_SIZE-1)) & DVMA_PAGE_MASK);
308 
309 	baddr = get_baddr(len, align);
310 //	printk("using baddr %lx\n", baddr);
311 
312 	if(!dvma_map_iommu(kaddr, baddr, len))
313 		return (baddr + off);
314 
315 	printk("dvma_map failed kaddr %lx baddr %lx len %x\n", kaddr, baddr, len);
316 	BUG();
317 	return 0;
318 }
319 EXPORT_SYMBOL(dvma_map_align);
320 
321 void dvma_unmap(void *baddr)
322 {
323 	unsigned long addr;
324 
325 	addr = (unsigned long)baddr;
326 	/* check if this is a vme mapping */
327 	if(!(addr & 0x00f00000))
328 		addr |= 0xf00000;
329 
330 	free_baddr(addr);
331 
332 	return;
333 
334 }
335 EXPORT_SYMBOL(dvma_unmap);
336 
337 void *dvma_malloc_align(unsigned long len, unsigned long align)
338 {
339 	unsigned long kaddr;
340 	unsigned long baddr;
341 	unsigned long vaddr;
342 
343 	if(!len)
344 		return NULL;
345 
346 #ifdef DEBUG
347 	printk("dvma_malloc request %lx bytes\n", len);
348 #endif
349 	len = ((len + (DVMA_PAGE_SIZE-1)) & DVMA_PAGE_MASK);
350 
351         if((kaddr = __get_free_pages(GFP_ATOMIC, get_order(len))) == 0)
352 		return NULL;
353 
354 	if((baddr = (unsigned long)dvma_map_align(kaddr, len, align)) == 0) {
355 		free_pages(kaddr, get_order(len));
356 		return NULL;
357 	}
358 
359 	vaddr = dvma_btov(baddr);
360 
361 	if(dvma_map_cpu(kaddr, vaddr, len) < 0) {
362 		dvma_unmap((void *)baddr);
363 		free_pages(kaddr, get_order(len));
364 		return NULL;
365 	}
366 
367 #ifdef DEBUG
368 	printk("mapped %08lx bytes %08lx kern -> %08lx bus\n",
369 	       len, kaddr, baddr);
370 #endif
371 
372 	return (void *)vaddr;
373 
374 }
375 EXPORT_SYMBOL(dvma_malloc_align);
376 
377 void dvma_free(void *vaddr)
378 {
379 
380 	return;
381 
382 }
383 EXPORT_SYMBOL(dvma_free);
384