arch/ppc64/kernel/lmb.c

   1 /*
   2  * Procedures for interfacing to Open Firmware.
   3  *
   4  * Peter Bergner, IBM Corp.     June 2001.
   5  * Copyright (C) 2001 Peter Bergner.
   6  *
   7  *      This program is free software; you can redistribute it and/or
   8  *      modify it under the terms of the GNU General Public License
   9  *      as published by the Free Software Foundation; either version
  10  *      2 of the License, or (at your option) any later version.
  11  */
  12
  13 #include <linux/config.h>
  14 #include <linux/kernel.h>
  15 #include <linux/init.h>
  16 #include <linux/bitops.h>
  17 #include <asm/types.h>
  18 #include <asm/page.h>
  19 #include <asm/prom.h>
  20 #include <asm/lmb.h>
  21 #include <asm/abs_addr.h>
  22
  23 struct lmb lmb;
  24
  25 #undef DEBUG
  26
  27 void lmb_dump_all(void)
  28 {
  29 #ifdef DEBUG
  30         unsigned long i;
  31
  32         udbg_printf("lmb_dump_all:\n");
  33         udbg_printf("    memory.cnt               = 0x%lx\n",
  34                     lmb.memory.cnt);
  35         udbg_printf("    memory.size              = 0x%lx\n",
  36                     lmb.memory.size);
  37         for (i=0; i < lmb.memory.cnt ;i++) {
  38                 udbg_printf("    memory.region[0x%x].base       = 0x%lx\n",
  39                             i, lmb.memory.region[i].base);
  40                 udbg_printf("                 .physbase = 0x%lx\n",
  41                             lmb.memory.region[i].physbase);
  42                 udbg_printf("                 .size     = 0x%lx\n",
  43                             lmb.memory.region[i].size);
  44         }
  45
  46         udbg_printf("\n    reserved.cnt   = 0x%lx\n",
  47                     lmb.reserved.cnt);
  48         udbg_printf("    reserved.size    = 0x%lx\n",
  49                     lmb.reserved.size);
  50         for (i=0; i < lmb.reserved.cnt ;i++) {
  51                 udbg_printf("    reserved.region[0x%x].base       = 0x%lx\n",
  52                             i, lmb.reserved.region[i].base);
  53                 udbg_printf("                 .physbase = 0x%lx\n",
  54                             lmb.reserved.region[i].physbase);
  55                 udbg_printf("                 .size     = 0x%lx\n",
  56                             lmb.reserved.region[i].size);
  57         }
  58 #endif /* DEBUG */
  59 }
  60
  61 static unsigned long __init
  62 lmb_addrs_overlap(unsigned long base1, unsigned long size1,
  63                   unsigned long base2, unsigned long size2)
  64 {
  65         return ((base1 < (base2+size2)) && (base2 < (base1+size1)));
  66 }
  67
  68 static long __init
  69 lmb_addrs_adjacent(unsigned long base1, unsigned long size1,
  70                    unsigned long base2, unsigned long size2)
  71 {
  72         if (base2 == base1 + size1)
  73                 return 1;
  74         else if (base1 == base2 + size2)
  75                 return -1;
  76
  77         return 0;
  78 }
  79
  80 static long __init
  81 lmb_regions_adjacent(struct lmb_region *rgn, unsigned long r1, unsigned long r2)
  82 {
  83         unsigned long base1 = rgn->region[r1].base;
  84         unsigned long size1 = rgn->region[r1].size;
  85         unsigned long base2 = rgn->region[r2].base;
  86         unsigned long size2 = rgn->region[r2].size;
  87
  88         return lmb_addrs_adjacent(base1, size1, base2, size2);
  89 }
  90
  91 /* Assumption: base addr of region 1 < base addr of region 2 */
  92 static void __init
  93 lmb_coalesce_regions(struct lmb_region *rgn, unsigned long r1, unsigned long r2)
  94 {
  95         unsigned long i;
  96
  97         rgn->region[r1].size += rgn->region[r2].size;
  98         for (i=r2; i < rgn->cnt-1; i++) {
  99                 rgn->region[i].base = rgn->region[i+1].base;
 100                 rgn->region[i].physbase = rgn->region[i+1].physbase;
 101                 rgn->region[i].size = rgn->region[i+1].size;
 102         }
 103         rgn->cnt--;
 104 }
 105
 106 /* This routine called with relocation disabled. */
 107 void __init
 108 lmb_init(void)
 109 {
 110         /* Create a dummy zero size LMB which will get coalesced away later.
 111          * This simplifies the lmb_add() code below...
 112          */
 113         lmb.memory.region[0].base = 0;
 114         lmb.memory.region[0].size = 0;
 115         lmb.memory.cnt = 1;
 116
 117         /* Ditto. */
 118         lmb.reserved.region[0].base = 0;
 119         lmb.reserved.region[0].size = 0;
 120         lmb.reserved.cnt = 1;
 121 }
 122
 123 /* This routine called with relocation disabled. */
 124 void __init
 125 lmb_analyze(void)
 126 {
 127         unsigned long i;
 128         unsigned long mem_size = 0;
 129         unsigned long size_mask = 0;
 130 #ifdef CONFIG_MSCHUNKS
 131         unsigned long physbase = 0;
 132 #endif
 133
 134         for (i=0; i < lmb.memory.cnt; i++) {
 135                 unsigned long lmb_size;
 136
 137                 lmb_size = lmb.memory.region[i].size;
 138
 139 #ifdef CONFIG_MSCHUNKS
 140                 lmb.memory.region[i].physbase = physbase;
 141                 physbase += lmb_size;
 142 #else
 143                 lmb.memory.region[i].physbase = lmb.memory.region[i].base;
 144 #endif
 145                 mem_size += lmb_size;
 146                 size_mask |= lmb_size;
 147         }
 148
 149         lmb.memory.size = mem_size;
 150 }
 151
 152 /* This routine called with relocation disabled. */
 153 static long __init
 154 lmb_add_region(struct lmb_region *rgn, unsigned long base, unsigned long size)
 155 {
 156         unsigned long i, coalesced = 0;
 157         long adjacent;
 158
 159         /* First try and coalesce this LMB with another. */
 160         for (i=0; i < rgn->cnt; i++) {
 161                 unsigned long rgnbase = rgn->region[i].base;
 162                 unsigned long rgnsize = rgn->region[i].size;
 163
 164                 adjacent = lmb_addrs_adjacent(base,size,rgnbase,rgnsize);
 165                 if ( adjacent > 0 ) {
 166                         rgn->region[i].base -= size;
 167                         rgn->region[i].physbase -= size;
 168                         rgn->region[i].size += size;
 169                         coalesced++;
 170                         break;
 171                 }
 172                 else if ( adjacent < 0 ) {
 173                         rgn->region[i].size += size;
 174                         coalesced++;
 175                         break;
 176                 }
 177         }
 178
 179         if ((i < rgn->cnt-1) && lmb_regions_adjacent(rgn, i, i+1) ) {
 180                 lmb_coalesce_regions(rgn, i, i+1);
 181                 coalesced++;
 182         }
 183
 184         if ( coalesced ) {
 185                 return coalesced;
 186         } else if ( rgn->cnt >= MAX_LMB_REGIONS ) {
 187                 return -1;
 188         }
 189
 190         /* Couldn't coalesce the LMB, so add it to the sorted table. */
 191         for (i=rgn->cnt-1; i >= 0; i--) {
 192                 if (base < rgn->region[i].base) {
 193                         rgn->region[i+1].base = rgn->region[i].base;
 194                         rgn->region[i+1].physbase = rgn->region[i].physbase;
 195                         rgn->region[i+1].size = rgn->region[i].size;
 196                 }  else {
 197                         rgn->region[i+1].base = base;
 198                         rgn->region[i+1].physbase = lmb_abs_to_phys(base);
 199                         rgn->region[i+1].size = size;
 200                         break;
 201                 }
 202         }
 203         rgn->cnt++;
 204
 205         return 0;
 206 }
 207
 208 /* This routine called with relocation disabled. */
 209 long __init
 210 lmb_add(unsigned long base, unsigned long size)
 211 {
 212         struct lmb_region *_rgn = &(lmb.memory);
 213
 214         /* On pSeries LPAR systems, the first LMB is our RMO region. */
 215         if ( base == 0 )
 216                 lmb.rmo_size = size;
 217
 218         return lmb_add_region(_rgn, base, size);
 219
 220 }
 221
 222 long __init
 223 lmb_reserve(unsigned long base, unsigned long size)
 224 {
 225         struct lmb_region *_rgn = &(lmb.reserved);
 226
 227         return lmb_add_region(_rgn, base, size);
 228 }
 229
 230 long __init
 231 lmb_overlaps_region(struct lmb_region *rgn, unsigned long base, unsigned long size)
 232 {
 233         unsigned long i;
 234
 235         for (i=0; i < rgn->cnt; i++) {
 236                 unsigned long rgnbase = rgn->region[i].base;
 237                 unsigned long rgnsize = rgn->region[i].size;
 238                 if ( lmb_addrs_overlap(base,size,rgnbase,rgnsize) ) {
 239                         break;
 240                 }
 241         }
 242
 243         return (i < rgn->cnt) ? i : -1;
 244 }
 245
 246 unsigned long __init
 247 lmb_alloc(unsigned long size, unsigned long align)
 248 {
 249         return lmb_alloc_base(size, align, LMB_ALLOC_ANYWHERE);
 250 }
 251
 252 unsigned long __init
 253 lmb_alloc_base(unsigned long size, unsigned long align, unsigned long max_addr)
 254 {
 255         long i, j;
 256         unsigned long base = 0;
 257
 258         for (i=lmb.memory.cnt-1; i >= 0; i--) {
 259                 unsigned long lmbbase = lmb.memory.region[i].base;
 260                 unsigned long lmbsize = lmb.memory.region[i].size;
 261
 262                 if ( max_addr == LMB_ALLOC_ANYWHERE )
 263                         base = _ALIGN_DOWN(lmbbase+lmbsize-size, align);
 264                 else if ( lmbbase < max_addr )
 265                         base = _ALIGN_DOWN(min(lmbbase+lmbsize,max_addr)-size, align);
 266                 else
 267                         continue;
 268
 269                 while ( (lmbbase <= base) &&
 270                         ((j = lmb_overlaps_region(&lmb.reserved,base,size)) >= 0) ) {
 271                         base = _ALIGN_DOWN(lmb.reserved.region[j].base-size, align);
 272                 }
 273
 274                 if ( (base != 0) && (lmbbase <= base) )
 275                         break;
 276         }
 277
 278         if ( i < 0 )
 279                 return 0;
 280
 281         lmb_add_region(&lmb.reserved, base, size);
 282
 283         return base;
 284 }
 285
 286 unsigned long __init
 287 lmb_phys_mem_size(void)
 288 {
 289 #ifdef CONFIG_MSCHUNKS
 290         return lmb.memory.size;
 291 #else
 292         unsigned long total = 0;
 293         int i;
 294
 295         /* add all physical memory to the bootmem map */
 296         for (i=0; i < lmb.memory.cnt; i++)
 297                 total += lmb.memory.region[i].size;
 298         return total;
 299 #endif /* CONFIG_MSCHUNKS */
 300 }
 301
 302 unsigned long __init
 303 lmb_end_of_DRAM(void)
 304 {
 305         int idx = lmb.memory.cnt - 1;
 306
 307 #ifdef CONFIG_MSCHUNKS
 308         return (lmb.memory.region[idx].physbase + lmb.memory.region[idx].size);
 309 #else
 310         return (lmb.memory.region[idx].base + lmb.memory.region[idx].size);
 311 #endif /* CONFIG_MSCHUNKS */
 312
 313         return 0;
 314 }
 315
 316 /*
 317  * Truncate the lmb list to memory_limit if it's set
 318  * You must call lmb_analyze() after this.
 319  */
 320 void __init lmb_enforce_memory_limit(void)
 321 {
 322         extern unsigned long memory_limit;
 323         unsigned long i, limit;
 324
 325         if (! memory_limit)
 326                 return;
 327
 328         limit = memory_limit;
 329         for (i = 0; i < lmb.memory.cnt; i++) {
 330                 if (limit > lmb.memory.region[i].size) {
 331                         limit -= lmb.memory.region[i].size;
 332                         continue;
 333                 }
 334
 335                 lmb.memory.region[i].size = limit;
 336                 lmb.memory.cnt = i + 1;
 337                 break;
 338         }
 339 }