arch/sparc/prom/memory.c

   1 /* memory.c: Prom routine for acquiring various bits of information
   2  *           about RAM on the machine, both virtual and physical.
   3  *
   4  * Copyright (C) 1995, 2008 David S. Miller (davem@davemloft.net)
   5  * Copyright (C) 1997 Michael A. Griffith (grif@acm.org)
   6  */
   7
   8 #include <linux/kernel.h>
   9 #include <linux/sort.h>
  10 #include <linux/init.h>
  11
  12 #include <asm/openprom.h>
  13 #include <asm/oplib.h>
  14 #include <asm/page.h>
  15
  16 static int __init prom_meminit_v0(void)
  17 {
  18         struct linux_mlist_v0 *p;
  19         int index;
  20
  21         index = 0;
  22         for (p = *(romvec->pv_v0mem.v0_available); p; p = p->theres_more) {
  23                 sp_banks[index].base_addr = (unsigned long) p->start_adr;
  24                 sp_banks[index].num_bytes = p->num_bytes;
  25                 index++;
  26         }
  27
  28         return index;
  29 }
  30
  31 static int __init prom_meminit_v2(void)
  32 {
  33         struct linux_prom_registers reg[64];
  34         int node, size, num_ents, i;
  35
  36         node = prom_searchsiblings(prom_getchild(prom_root_node), "memory");
  37         size = prom_getproperty(node, "available", (char *) reg, sizeof(reg));
  38         num_ents = size / sizeof(struct linux_prom_registers);
  39
  40         for (i = 0; i < num_ents; i++) {
  41                 sp_banks[i].base_addr = reg[i].phys_addr;
  42                 sp_banks[i].num_bytes = reg[i].reg_size;
  43         }
  44
  45         return num_ents;
  46 }
  47
  48 static int sp_banks_cmp(const void *a, const void *b)
  49 {
  50         const struct sparc_phys_banks *x = a, *y = b;
  51
  52         if (x->base_addr > y->base_addr)
  53                 return 1;
  54         if (x->base_addr < y->base_addr)
  55                 return -1;
  56         return 0;
  57 }
  58
  59 /* Initialize the memory lists based upon the prom version. */
  60 void __init prom_meminit(void)
  61 {
  62         int i, num_ents = 0;
  63
  64         switch (prom_vers) {
  65         case PROM_V0:
  66                 num_ents = prom_meminit_v0();
  67                 break;
  68
  69         case PROM_V2:
  70         case PROM_V3:
  71                 num_ents = prom_meminit_v2();
  72                 break;
  73
  74         default:
  75                 break;
  76         }
  77         sort(sp_banks, num_ents, sizeof(struct sparc_phys_banks),
  78              sp_banks_cmp, NULL);
  79
  80         /* Sentinel.  */
  81         sp_banks[num_ents].base_addr = 0xdeadbeef;
  82         sp_banks[num_ents].num_bytes = 0;
  83
  84         for (i = 0; i < num_ents; i++)
  85                 sp_banks[i].num_bytes &= PAGE_MASK;
  86 }