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         phandle node;
  35         int size, num_ents, i;
  36
  37         node = prom_searchsiblings(prom_getchild(prom_root_node), "memory");
  38         size = prom_getproperty(node, "available", (char *) reg, sizeof(reg));
  39         num_ents = size / sizeof(struct linux_prom_registers);
  40
  41         for (i = 0; i < num_ents; i++) {
  42                 sp_banks[i].base_addr = reg[i].phys_addr;
  43                 sp_banks[i].num_bytes = reg[i].reg_size;
  44         }
  45
  46         return num_ents;
  47 }
  48
  49 static int sp_banks_cmp(const void *a, const void *b)
  50 {
  51         const struct sparc_phys_banks *x = a, *y = b;
  52
  53         if (x->base_addr > y->base_addr)
  54                 return 1;
  55         if (x->base_addr < y->base_addr)
  56                 return -1;
  57         return 0;
  58 }
  59
  60 /* Initialize the memory lists based upon the prom version. */
  61 void __init prom_meminit(void)
  62 {
  63         int i, num_ents = 0;
  64
  65         switch (prom_vers) {
  66         case PROM_V0:
  67                 num_ents = prom_meminit_v0();
  68                 break;
  69
  70         case PROM_V2:
  71         case PROM_V3:
  72                 num_ents = prom_meminit_v2();
  73                 break;
  74
  75         default:
  76                 break;
  77         }
  78         sort(sp_banks, num_ents, sizeof(struct sparc_phys_banks),
  79              sp_banks_cmp, NULL);
  80
  81         /* Sentinel.  */
  82         sp_banks[num_ents].base_addr = 0xdeadbeef;
  83         sp_banks[num_ents].num_bytes = 0;
  84
  85         for (i = 0; i < num_ents; i++)
  86                 sp_banks[i].num_bytes &= PAGE_MASK;
  87 }