LXR linux/arch/sparc/prom/memory.c

   1// SPDX-License-Identifier: GPL-2.0
   2/* memory.c: Prom routine for acquiring various bits of information
   3 *           about RAM on the machine, both virtual and physical.
   4 *
   5 * Copyright (C) 1995, 2008 David S. Miller (davem@davemloft.net)
   6 * Copyright (C) 1997 Michael A. Griffith (grif@acm.org)
   7 */
   8
   9#include <linux/kernel.h>
  10#include <linux/sort.h>
  11#include <linux/init.h>
  12
  13#include <asm/openprom.h>
  14#include <asm/oplib.h>
  15#include <asm/page.h>
  16
  17static int __init prom_meminit_v0(void)
  18{
  19        struct linux_mlist_v0 *p;
  20        int index;
  21
  22        index = 0;
  23        for (p = *(romvec->pv_v0mem.v0_available); p; p = p->theres_more) {
  24                sp_banks[index].base_addr = (unsigned long) p->start_adr;
  25                sp_banks[index].num_bytes = p->num_bytes;
  26                index++;
  27        }
  28
  29        return index;
  30}
  31
  32static int __init prom_meminit_v2(void)
  33{
  34        struct linux_prom_registers reg[64];
  35        phandle node;
  36        int size, num_ents, i;
  37
  38        node = prom_searchsiblings(prom_getchild(prom_root_node), "memory");
  39        size = prom_getproperty(node, "available", (char *) reg, sizeof(reg));
  40        num_ents = size / sizeof(struct linux_prom_registers);
  41
  42        for (i = 0; i < num_ents; i++) {
  43                sp_banks[i].base_addr = reg[i].phys_addr;
  44                sp_banks[i].num_bytes = reg[i].reg_size;
  45        }
  46
  47        return num_ents;
  48}
  49
  50static int sp_banks_cmp(const void *a, const void *b)
  51{
  52        const struct sparc_phys_banks *x = a, *y = b;
  53
  54        if (x->base_addr > y->base_addr)
  55                return 1;
  56        if (x->base_addr < y->base_addr)
  57                return -1;
  58        return 0;
  59}
  60
  61/* Initialize the memory lists based upon the prom version. */
  62void __init prom_meminit(void)
  63{
  64        int i, num_ents = 0;
  65
  66        switch (prom_vers) {
  67        case PROM_V0:
  68                num_ents = prom_meminit_v0();
  69                break;
  70
  71        case PROM_V2:
  72        case PROM_V3:
  73                num_ents = prom_meminit_v2();
  74                break;
  75
  76        default:
  77                break;
  78        }
  79        sort(sp_banks, num_ents, sizeof(struct sparc_phys_banks),
  80             sp_banks_cmp, NULL);
  81
  82        /* Sentinel.  */
  83        sp_banks[num_ents].base_addr = 0xdeadbeef;
  84        sp_banks[num_ents].num_bytes = 0;
  85
  86        for (i = 0; i < num_ents; i++)
  87                sp_banks[i].num_bytes &= PAGE_MASK;
  88}
  89