xref: /openbmc/linux/arch/m68k/sun3/sun3dvma.c (revision d236d361)
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 	pr_info("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 		pr_info("dvma entry: %08x len %08lx\n",
74 			(i << DVMA_PAGE_SHIFT) + DVMA_START, iommu_use[i]);
75 	}
76 
77 	pr_info("%d entries in use total\n", j);
78 
79 	pr_info("allocation/free calls: %lu/%lu\n", dvma_allocs, dvma_frees);
80 	pr_info("allocation/free bytes: %Lx/%Lx\n", dvma_alloc_bytes,
81 		dvma_free_bytes);
82 }
83 
84 static void print_holes(struct list_head *holes)
85 {
86 
87 	struct list_head *cur;
88 	struct hole *hole;
89 
90 	pr_info("listing dvma holes\n");
91 	list_for_each(cur, holes) {
92 		hole = list_entry(cur, struct hole, list);
93 
94 		if((hole->start == 0) && (hole->end == 0) && (hole->size == 0))
95 			continue;
96 
97 		pr_info("hole: start %08lx end %08lx size %08lx\n",
98 			hole->start, hole->end, hole->size);
99 	}
100 
101 	pr_info("end of hole listing...\n");
102 }
103 #endif /* DVMA_DEBUG */
104 
105 static inline int refill(void)
106 {
107 
108 	struct hole *hole;
109 	struct hole *prev = NULL;
110 	struct list_head *cur;
111 	int ret = 0;
112 
113 	list_for_each(cur, &hole_list) {
114 		hole = list_entry(cur, struct hole, list);
115 
116 		if(!prev) {
117 			prev = hole;
118 			continue;
119 		}
120 
121 		if(hole->end == prev->start) {
122 			hole->size += prev->size;
123 			hole->end = prev->end;
124 			list_move(&(prev->list), &hole_cache);
125 			ret++;
126 		}
127 
128 	}
129 
130 	return ret;
131 }
132 
133 static inline struct hole *rmcache(void)
134 {
135 	struct hole *ret;
136 
137 	if(list_empty(&hole_cache)) {
138 		if(!refill()) {
139 			pr_crit("out of dvma hole cache!\n");
140 			BUG();
141 		}
142 	}
143 
144 	ret = list_entry(hole_cache.next, struct hole, list);
145 	list_del(&(ret->list));
146 
147 	return ret;
148 
149 }
150 
151 static inline unsigned long get_baddr(int len, unsigned long align)
152 {
153 
154 	struct list_head *cur;
155 	struct hole *hole;
156 
157 	if(list_empty(&hole_list)) {
158 #ifdef DVMA_DEBUG
159 		pr_crit("out of dvma holes! (printing hole cache)\n");
160 		print_holes(&hole_cache);
161 		print_use();
162 #endif
163 		BUG();
164 	}
165 
166 	list_for_each(cur, &hole_list) {
167 		unsigned long newlen;
168 
169 		hole = list_entry(cur, struct hole, list);
170 
171 		if(align > DVMA_PAGE_SIZE)
172 			newlen = len + ((hole->end - len) & (align-1));
173 		else
174 			newlen = len;
175 
176 		if(hole->size > newlen) {
177 			hole->end -= newlen;
178 			hole->size -= newlen;
179 			dvma_entry_use(hole->end) = newlen;
180 #ifdef DVMA_DEBUG
181 			dvma_allocs++;
182 			dvma_alloc_bytes += newlen;
183 #endif
184 			return hole->end;
185 		} else if(hole->size == newlen) {
186 			list_move(&(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 	pr_crit("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 __init 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 	iommu_use = alloc_bootmem(IOMMU_TOTAL_ENTRIES * sizeof(unsigned long));
270 
271 	dvma_unmap_iommu(DVMA_START, DVMA_SIZE);
272 
273 #ifdef CONFIG_SUN3
274 	sun3_dvma_init();
275 #endif
276 
277 }
278 
279 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 //		pr_err("error: kaddr %lx len %x\n", kaddr, len);
290 //		*(int *)4 = 0;
291 		return 0;
292 	}
293 
294 	pr_debug("dvma_map request %08x bytes from %08lx\n", len, kaddr);
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 //	pr_info("using baddr %lx\n", baddr);
307 
308 	if(!dvma_map_iommu(kaddr, baddr, len))
309 		return (baddr + off);
310 
311 	pr_crit("dvma_map failed kaddr %lx baddr %lx len %x\n", kaddr, baddr,
312 	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 	pr_debug("dvma_malloc request %lx bytes\n", len);
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 	pr_debug("mapped %08lx bytes %08lx kern -> %08lx bus\n", len, kaddr,
363 		 baddr);
364 
365 	return (void *)vaddr;
366 
367 }
368 EXPORT_SYMBOL(dvma_malloc_align);
369 
370 void dvma_free(void *vaddr)
371 {
372 
373 	return;
374 
375 }
376 EXPORT_SYMBOL(dvma_free);
377