memory.c

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/*
 * memory.c: PROM library functions for acquiring/using memory descriptors
 *           given to us from the ARCS firmware.
 *
 * Copyright (C) 1996 by David S. Miller
 * Copyright (C) 1999, 2000, 2001 by Ralf Baechle
 * Copyright (C) 1999, 2000 by Silicon Graphics, Inc.
 *
 * PROM library functions for acquiring/using memory descriptors given to us
 * from the ARCS firmware.  This is only used when CONFIG_ARC_MEMORY is set
 * because on some machines like SGI IP27 the ARC memory configuration data
 * completly bogus and alternate easier to use mechanisms are available.
 */
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/bootmem.h>
#include <linux/swap.h>

#include <asm/sgialib.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/bootinfo.h>

#undef DEBUG

/*
 * For ARC firmware memory functions the unit of meassuring memory is always
 * a 4k page of memory
 */
#define ARC_PAGE_SHIFT  12

struct linux_mdesc * __init ArcGetMemoryDescriptor(struct linux_mdesc *Current)
{
    return (struct linux_mdesc *) ARC_CALL1(get_mdesc, Current);
}

#ifdef DEBUG /* convenient for debugging */
static char *arcs_mtypes[8] = {
    "Exception Block",
    "ARCS Romvec Page",
    "Free/Contig RAM",
    "Generic Free RAM",
    "Bad Memory",
    "Standalone Program Pages",
    "ARCS Temp Storage Area",
    "ARCS Permanent Storage Area"
};

static char *arc_mtypes[8] = {
    "Exception Block",
    "SystemParameterBlock",
    "FreeMemory",
    "Bad Memory",
    "LoadedProgram",
    "FirmwareTemporary",
    "FirmwarePermanent",
    "FreeContiguous"
};
#define mtypes(a) (prom_flags & PROM_FLAG_ARCS) ? arcs_mtypes[a.arcs] \
                        : arc_mtypes[a.arc]
#endif

static inline int memtype_classify_arcs(union linux_memtypes type)
{
    switch (type.arcs) {
    case arcs_fcontig:
    case arcs_free:
        return BOOT_MEM_RAM;
    case arcs_atmp:
        return BOOT_MEM_ROM_DATA;
    case arcs_eblock:
    case arcs_rvpage:
    case arcs_bmem:
    case arcs_prog:
    case arcs_aperm:
        return BOOT_MEM_RESERVED;
    default:
        BUG();
    }
    while(1);               /* Nuke warning.  */
}

static inline int memtype_classify_arc(union linux_memtypes type)
{
    switch (type.arc) {
    case arc_free:
    case arc_fcontig:
        return BOOT_MEM_RAM;
    case arc_atmp:
        return BOOT_MEM_ROM_DATA;
    case arc_eblock:
    case arc_rvpage:
    case arc_bmem:
    case arc_prog:
    case arc_aperm:
        return BOOT_MEM_RESERVED;
    default:
        BUG();
    }
    while(1);               /* Nuke warning.  */
}

static int __init prom_memtype_classify(union linux_memtypes type)
{
    if (prom_flags & PROM_FLAG_ARCS)    /* SGI is ``different'' ... */
        return memtype_classify_arcs(type);

    return memtype_classify_arc(type);
}

void __init prom_meminit(void)
{
    struct linux_mdesc *p;

#ifdef DEBUG
    int i = 0;

    printk("ARCS MEMORY DESCRIPTOR dump:\n");
    p = ArcGetMemoryDescriptor(PROM_NULL_MDESC);
    while(p) {
        printk("[%d,%p]: base<%08lx> pages<%08lx> type<%s>\n",
               i, p, p->base, p->pages, mtypes(p->type));
        p = ArcGetMemoryDescriptor(p);
        i++;
    }
#endif

    p = PROM_NULL_MDESC;
    while ((p = ArcGetMemoryDescriptor(p))) {
        unsigned long base, size;
        long type;

        base = p->base << ARC_PAGE_SHIFT;
        size = p->pages << ARC_PAGE_SHIFT;
        type = prom_memtype_classify(p->type);

        add_memory_region(base, size, type);
    }
}

void __init prom_free_prom_memory(void)
{
    unsigned long addr;
    int i;

    if (prom_flags & PROM_FLAG_DONT_FREE_TEMP)
        return;

    for (i = 0; i < boot_mem_map.nr_map; i++) {
        if (boot_mem_map.map[i].type != BOOT_MEM_ROM_DATA)
            continue;

        addr = boot_mem_map.map[i].addr;
        free_init_pages("prom memory",
                addr, addr + boot_mem_map.map[i].size);
    }
}