arch/mips/arc/memory.c

   1 /*
   2  * memory.c: PROM library functions for acquiring/using memory descriptors
   3  *           given to us from the ARCS firmware.
   4  *
   5  * Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
   6  *
   7  * $Id: memory.c,v 1.10 2000/01/27 23:21:57 ralf Exp $
   8  */
   9 #include <linux/init.h>
  10 #include <linux/kernel.h>
  11 #include <linux/types.h>
  12 #include <linux/sched.h>
  13 #include <linux/mm.h>
  14 #include <linux/bootmem.h>
  15 #include <linux/swap.h>
  16
  17 #include <asm/sgialib.h>
  18 #include <asm/page.h>
  19 #include <asm/pgtable.h>
  20 #include <asm/bootinfo.h>
  21
  22 #undef DEBUG
  23
  24 extern char _end;
  25
  26 struct linux_mdesc * __init
  27 ArcGetMemoryDescriptor(struct linux_mdesc *Current)
  28 {
  29         return romvec->get_mdesc(Current);
  30 }
  31
  32 #ifdef DEBUG /* convenient for debugging */
  33 static char *arcs_mtypes[8] = {
  34         "Exception Block",
  35         "ARCS Romvec Page",
  36         "Free/Contig RAM",
  37         "Generic Free RAM",
  38         "Bad Memory",
  39         "Standlong Program Pages",
  40         "ARCS Temp Storage Area",
  41         "ARCS Permanent Storage Area"
  42 };
  43
  44 static char *arc_mtypes[8] = {
  45         "Exception Block",
  46         "SystemParameterBlock",
  47         "FreeMemory",
  48         "Bad Memory",
  49         "LoadedProgram",
  50         "FirmwareTemporary",
  51         "FirmwarePermanent",
  52         "FreeContigiuous"
  53 };
  54 #define mtypes(a) (prom_flags & PROM_FLAG_ARCS) ? arcs_mtypes[a.arcs] : arc_mtypes[a.arc]
  55 #endif
  56
  57 static struct prom_pmemblock pblocks[PROM_MAX_PMEMBLOCKS];
  58
  59 #define MEMTYPE_DONTUSE   0
  60 #define MEMTYPE_PROM      1
  61 #define MEMTYPE_FREE      2
  62
  63 static inline int memtype_classify_arcs (union linux_memtypes type)
  64 {
  65         switch (type.arcs) {
  66         case arcs_fcontig:
  67         case arcs_free:
  68                 return MEMTYPE_FREE;
  69         case arcs_atmp:
  70                 return MEMTYPE_PROM;
  71         case arcs_eblock:
  72         case arcs_rvpage:
  73         case arcs_bmem:
  74         case arcs_prog:
  75         case arcs_aperm:
  76                 return MEMTYPE_DONTUSE;
  77         default:
  78                 BUG();
  79         }
  80         while(1);                               /* Nuke warning.  */
  81 }
  82
  83 static inline int memtype_classify_arc (union linux_memtypes type)
  84 {
  85         switch (type.arc) {
  86         case arc_free:
  87         case arc_fcontig:
  88                 return MEMTYPE_FREE;
  89         case arc_atmp:
  90                 return MEMTYPE_PROM;
  91         case arc_eblock:
  92         case arc_rvpage:
  93         case arc_bmem:
  94         case arc_prog:
  95         case arc_aperm:
  96                 return MEMTYPE_DONTUSE;
  97         default:
  98                 BUG();
  99         }
 100         while(1);                               /* Nuke warning.  */
 101 }
 102
 103 static int __init prom_memtype_classify (union linux_memtypes type)
 104 {
 105         if (prom_flags & PROM_FLAG_ARCS)        /* SGI is ``different'' ...  */
 106                 return memtype_classify_arcs(type);
 107
 108         return memtype_classify_arc(type);
 109 }
 110
 111 static inline unsigned long find_max_low_pfn(void)
 112 {
 113         struct prom_pmemblock *p, *highest;
 114         unsigned long pfn;
 115
 116         p = pblocks;
 117         highest = 0;
 118         while (p->size != 0) {
 119                 if (!highest || p->base > highest->base)
 120                         highest = p;
 121                 p++;
 122         }
 123
 124         pfn = (highest->base + highest->size) >> PAGE_SHIFT;
 125 #ifdef DEBUG
 126         prom_printf("find_max_low_pfn: 0x%lx pfns.\n", pfn);
 127 #endif
 128         return pfn;
 129 }
 130
 131 static inline struct prom_pmemblock *find_largest_memblock(void)
 132 {
 133         struct prom_pmemblock *p, *largest;
 134
 135         p = pblocks;
 136         largest = 0;
 137         while (p->size != 0) {
 138                 if (!largest || p->size > largest->size)
 139                         largest = p;
 140                 p++;
 141         }
 142
 143         return largest;
 144 }
 145
 146 void __init prom_meminit(void)
 147 {
 148         struct prom_pmemblock *largest;
 149         unsigned long bootmap_size;
 150         struct linux_mdesc *p;
 151         int totram;
 152         int i = 0;
 153
 154 #ifdef DEBUG
 155         prom_printf("ARCS MEMORY DESCRIPTOR dump:\n");
 156         p = ArcGetMemoryDescriptor(PROM_NULL_MDESC);
 157         while(p) {
 158                 prom_printf("[%d,%p]: base<%08lx> pages<%08lx> type<%s>\n",
 159                             i, p, p->base, p->pages, mtypes(p->type));
 160                 p = ArcGetMemoryDescriptor(p);
 161                 i++;
 162         }
 163 #endif
 164
 165         totram = 0;
 166         i = 0;
 167         p = PROM_NULL_MDESC;
 168         while ((p = ArcGetMemoryDescriptor(p))) {
 169                 pblocks[i].type = prom_memtype_classify(p->type);
 170                 pblocks[i].base = p->base << PAGE_SHIFT;
 171                 pblocks[i].size = p->pages << PAGE_SHIFT;
 172
 173                 switch (pblocks[i].type) {
 174                 case MEMTYPE_FREE:
 175                         totram += pblocks[i].size;
 176 #ifdef DEBUG
 177                         prom_printf("free_chunk[%d]: base=%08lx size=%x\n",
 178                                     i, pblocks[i].base,
 179                                     pblocks[i].size);
 180 #endif
 181                         i++;
 182                         break;
 183                 case MEMTYPE_PROM:
 184 #ifdef DEBUG
 185                         prom_printf("prom_chunk[%d]: base=%08lx size=%x\n",
 186                                     i, pblocks[i].base,
 187                                     pblocks[i].size);
 188 #endif
 189                         i++;
 190                         break;
 191                 default:
 192                         break;
 193                 }
 194         }
 195         pblocks[i].size = 0;
 196
 197         max_low_pfn = find_max_low_pfn();
 198         largest = find_largest_memblock();
 199         bootmap_size = init_bootmem(largest->base >> PAGE_SHIFT, max_low_pfn);
 200
 201         for (i = 0; pblocks[i].size; i++)
 202                 if (pblocks[i].type == MEMTYPE_FREE)
 203                         free_bootmem(pblocks[i].base, pblocks[i].size);
 204
 205         /* This test is simpleminded.  It will fail if the bootmem bitmap
 206            falls into multiple adjacent ARC memory areas.  */
 207         if (bootmap_size > largest->size) {
 208                 prom_printf("CRITIAL: overwriting PROM data.\n");
 209                 BUG();
 210         }
 211         reserve_bootmem(largest->base, bootmap_size);
 212
 213         printk("PROMLIB: Total free ram %dK / %dMB.\n",
 214                totram >> 10, totram >> 20);
 215 }
 216
 217 void __init
 218 prom_free_prom_memory (void)
 219 {
 220         struct prom_pmemblock *p;
 221         unsigned long freed = 0;
 222         unsigned long addr;
 223
 224         for (p = pblocks; p->size != 0; p++) {
 225                 if (p->type != MEMTYPE_PROM)
 226                         continue;
 227
 228                 addr = PAGE_OFFSET + p->base;
 229                 while (addr < p->base + p->size) {
 230                         ClearPageReserved(mem_map + MAP_NR(addr));
 231                         set_page_count(mem_map + MAP_NR(addr), 1);
 232                         free_page(addr);
 233                         addr += PAGE_SIZE;
 234                         freed += PAGE_SIZE;
 235                 }
 236         }
 237         printk("Freeing prom memory: %ldkb freed\n", freed >> 10);
 238 }