memory.c

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/* memory.c: Prom routine for acquiring various bits of information
 *           about RAM on the machine, both virtual and physical.
 *
 * Copyright (C) 1995, 2008 David S. Miller ([email protected])
 * Copyright (C) 1997 Michael A. Griffith ([email protected])
 */

#include <linux/kernel.h>
#include <linux/sort.h>
#include <linux/init.h>

#include <asm/openprom.h>
#include <asm/oplib.h>
#include <asm/page.h>

static int __init prom_meminit_v0(void)
{
    struct linux_mlist_v0 *p;
    int index;

    index = 0;
    for (p = *(romvec->pv_v0mem.v0_available); p; p = p->theres_more) {
        sp_banks[index].base_addr = (unsigned long) p->start_adr;
        sp_banks[index].num_bytes = p->num_bytes;
        index++;
    }

    return index;
}

static int __init prom_meminit_v2(void)
{
    struct linux_prom_registers reg[64];
    phandle node;
    int size, num_ents, i;

    node = prom_searchsiblings(prom_getchild(prom_root_node), "memory");
    size = prom_getproperty(node, "available", (char *) reg, sizeof(reg));
    num_ents = size / sizeof(struct linux_prom_registers);

    for (i = 0; i < num_ents; i++) {
        sp_banks[i].base_addr = reg[i].phys_addr;
        sp_banks[i].num_bytes = reg[i].reg_size;
    }

    return num_ents;
}

static int sp_banks_cmp(const void *a, const void *b)
{
    const struct sparc_phys_banks *x = a, *y = b;

    if (x->base_addr > y->base_addr)
        return 1;
    if (x->base_addr < y->base_addr)
        return -1;
    return 0;
}

/* Initialize the memory lists based upon the prom version. */
void __init prom_meminit(void)
{
    int i, num_ents = 0;

    switch (prom_vers) {
    case PROM_V0:
        num_ents = prom_meminit_v0();
        break;

    case PROM_V2:
    case PROM_V3:
        num_ents = prom_meminit_v2();
        break;

    default:
        break;
    }
    sort(sp_banks, num_ents, sizeof(struct sparc_phys_banks),
         sp_banks_cmp, NULL);

    /* Sentinel.  */
    sp_banks[num_ents].base_addr = 0xdeadbeef;
    sp_banks[num_ents].num_bytes = 0;

    for (i = 0; i < num_ents; i++)
        sp_banks[i].num_bytes &= PAGE_MASK;
}