arch/m68k/sun3/sun3dvma.c

   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 }