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/kernel.h>
  10 #include <linux/mm.h>
  11 #include <linux/list.h>
  12
  13 #include <asm/page.h>
  14 #include <asm/pgtable.h>
  15 #include <asm/dvma.h>
  16
  17 #undef DVMA_DEBUG
  18
  19 #ifdef CONFIG_SUN3X
  20 extern void dvma_unmap_iommu(unsigned long baddr, int len);
  21 #else
  22 static inline void dvma_unmap_iommu(unsigned long a, int b)
  23 {
  24 }
  25 #endif
  26
  27 #ifdef CONFIG_SUN3
  28 extern void sun3_dvma_init(void);
  29 #endif
  30
  31 unsigned long iommu_use[IOMMU_TOTAL_ENTRIES];
  32
  33 #define dvma_index(baddr) ((baddr - DVMA_START) >> DVMA_PAGE_SHIFT)
  34
  35 #define dvma_entry_use(baddr)           (iommu_use[dvma_index(baddr)])
  36
  37 struct hole {
  38         unsigned long start;
  39         unsigned long end;
  40         unsigned long size;
  41         struct list_head list;
  42 };
  43
  44 static struct list_head hole_list;
  45 static struct list_head hole_cache;
  46 static struct hole initholes[64];
  47
  48 #ifdef DVMA_DEBUG
  49
  50 static unsigned long dvma_allocs;
  51 static unsigned long dvma_frees;
  52 static unsigned long long dvma_alloc_bytes;
  53 static unsigned long long dvma_free_bytes;
  54
  55 static void print_use(void)
  56 {
  57
  58         int i;
  59         int j = 0;
  60
  61         printk("dvma entry usage:\n");
  62
  63         for(i = 0; i < IOMMU_TOTAL_ENTRIES; i++) {
  64                 if(!iommu_use[i])
  65                         continue;
  66
  67                 j++;
  68
  69                 printk("dvma entry: %08lx len %08lx\n",
  70                        ( i << DVMA_PAGE_SHIFT) + DVMA_START,
  71                        iommu_use[i]);
  72         }
  73
  74         printk("%d entries in use total\n", j);
  75
  76         printk("allocation/free calls: %lu/%lu\n", dvma_allocs, dvma_frees);
  77         printk("allocation/free bytes: %Lx/%Lx\n", dvma_alloc_bytes,
  78                dvma_free_bytes);
  79 }
  80
  81 static void print_holes(struct list_head *holes)
  82 {
  83
  84         struct list_head *cur;
  85         struct hole *hole;
  86
  87         printk("listing dvma holes\n");
  88         list_for_each(cur, holes) {
  89                 hole = list_entry(cur, struct hole, list);
  90
  91                 if((hole->start == 0) && (hole->end == 0) && (hole->size == 0))
  92                         continue;
  93
  94                 printk("hole: start %08lx end %08lx size %08lx\n", hole->start, hole->end, hole->size);
  95         }
  96
  97         printk("end of hole listing...\n");
  98
  99 }
 100 #endif /* DVMA_DEBUG */
 101
 102 static inline int refill(void)
 103 {
 104
 105         struct hole *hole;
 106         struct hole *prev = NULL;
 107         struct list_head *cur;
 108         int ret = 0;
 109
 110         list_for_each(cur, &hole_list) {
 111                 hole = list_entry(cur, struct hole, list);
 112
 113                 if(!prev) {
 114                         prev = hole;
 115                         continue;
 116                 }
 117
 118                 if(hole->end == prev->start) {
 119                         hole->size += prev->size;
 120                         hole->end = prev->end;
 121                         list_del(&(prev->list));
 122                         list_add(&(prev->list), &hole_cache);
 123                         ret++;
 124                 }
 125
 126         }
 127
 128         return ret;
 129 }
 130
 131 static inline struct hole *rmcache(void)
 132 {
 133         struct hole *ret;
 134
 135         if(list_empty(&hole_cache)) {
 136                 if(!refill()) {
 137                         printk("out of dvma hole cache!\n");
 138                         BUG();
 139                 }
 140         }
 141
 142         ret = list_entry(hole_cache.next, struct hole, list);
 143         list_del(&(ret->list));
 144
 145         return ret;
 146
 147 }
 148
 149 static inline unsigned long get_baddr(int len, unsigned long align)
 150 {
 151
 152         struct list_head *cur;
 153         struct hole *hole;
 154
 155         if(list_empty(&hole_list)) {
 156 #ifdef DVMA_DEBUG
 157                 printk("out of dvma holes! (printing hole cache)\n");
 158                 print_holes(&hole_cache);
 159                 print_use();
 160 #endif
 161                 BUG();
 162         }
 163
 164         list_for_each(cur, &hole_list) {
 165                 unsigned long newlen;
 166
 167                 hole = list_entry(cur, struct hole, list);
 168
 169                 if(align > DVMA_PAGE_SIZE)
 170                         newlen = len + ((hole->end - len) & (align-1));
 171                 else
 172                         newlen = len;
 173
 174                 if(hole->size > newlen) {
 175                         hole->end -= newlen;
 176                         hole->size -= newlen;
 177                         dvma_entry_use(hole->end) = newlen;
 178 #ifdef DVMA_DEBUG
 179                         dvma_allocs++;
 180                         dvma_alloc_bytes += newlen;
 181 #endif
 182                         return hole->end;
 183                 } else if(hole->size == newlen) {
 184                         list_del(&(hole->list));
 185                         list_add(&(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
 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
 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 #ifdef DEBUG
 344         printk("dvma_malloc request %lx bytes\n", len);
 345 #endif
 346         len = ((len + (DVMA_PAGE_SIZE-1)) & DVMA_PAGE_MASK);
 347
 348         if((kaddr = __get_free_pages(GFP_ATOMIC, get_order(len))) == 0)
 349                 return NULL;
 350
 351         if((baddr = (unsigned long)dvma_map_align(kaddr, len, align)) == 0) {
 352                 free_pages(kaddr, get_order(len));
 353                 return NULL;
 354         }
 355
 356         vaddr = dvma_btov(baddr);
 357
 358         if(dvma_map_cpu(kaddr, vaddr, len) < 0) {
 359                 dvma_unmap((void *)baddr);
 360                 free_pages(kaddr, get_order(len));
 361                 return NULL;
 362         }
 363
 364 #ifdef DEBUG
 365         printk("mapped %08lx bytes %08lx kern -> %08lx bus\n",
 366                len, kaddr, baddr);
 367 #endif
 368
 369         return (void *)vaddr;
 370
 371 }
 372
 373 void dvma_free(void *vaddr)
 374 {
 375
 376         return;
 377
 378 }