setup.c

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/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 1995 Linus Torvalds
 * Copyright (C) 1995 Waldorf Electronics
 * Copyright (C) 1994, 95, 96, 97, 98, 99, 2000, 01, 02, 03  Ralf Baechle
 * Copyright (C) 1996 Stoned Elipot
 * Copyright (C) 1999 Silicon Graphics, Inc.
 * Copyright (C) 2000, 2001, 2002, 2007  Maciej W. Rozycki
 */
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/export.h>
#include <linux/screen_info.h>
#include <linux/memblock.h>
#include <linux/bootmem.h>
#include <linux/initrd.h>
#include <linux/root_dev.h>
#include <linux/highmem.h>
#include <linux/console.h>
#include <linux/pfn.h>
#include <linux/debugfs.h>

#include <asm/addrspace.h>
#include <asm/bootinfo.h>
#include <asm/bugs.h>
#include <asm/cache.h>
#include <asm/cpu.h>
#include <asm/sections.h>
#include <asm/setup.h>
#include <asm/smp-ops.h>
#include <asm/prom.h>

struct cpuinfo_mips cpu_data[NR_CPUS] __read_mostly;

EXPORT_SYMBOL(cpu_data);

#ifdef CONFIG_VT
struct screen_info screen_info;
#endif

/*
 * Despite it's name this variable is even if we don't have PCI
 */
unsigned int PCI_DMA_BUS_IS_PHYS;

EXPORT_SYMBOL(PCI_DMA_BUS_IS_PHYS);

/*
 * Setup information
 *
 * These are initialized so they are in the .data section
 */
unsigned long mips_machtype __read_mostly = MACH_UNKNOWN;

EXPORT_SYMBOL(mips_machtype);

struct boot_mem_map boot_mem_map;

static char __initdata command_line[COMMAND_LINE_SIZE];
char __initdata arcs_cmdline[COMMAND_LINE_SIZE];

#ifdef CONFIG_CMDLINE_BOOL
static char __initdata builtin_cmdline[COMMAND_LINE_SIZE] = CONFIG_CMDLINE;
#endif

/*
 * mips_io_port_base is the begin of the address space to which x86 style
 * I/O ports are mapped.
 */
const unsigned long mips_io_port_base = -1;
EXPORT_SYMBOL(mips_io_port_base);

static struct resource code_resource = { .name = "Kernel code", };
static struct resource data_resource = { .name = "Kernel data", };

void __init add_memory_region(phys_t start, phys_t size, long type)
{
    int x = boot_mem_map.nr_map;
    int i;

    /* Sanity check */
    if (start + size < start) {
        pr_warning("Trying to add an invalid memory region, skipped\n");
        return;
    }

    /*
     * Try to merge with existing entry, if any.
     */
    for (i = 0; i < boot_mem_map.nr_map; i++) {
        struct boot_mem_map_entry *entry = boot_mem_map.map + i;
        unsigned long top;

        if (entry->type != type)
            continue;

        if (start + size < entry->addr)
            continue;           /* no overlap */

        if (entry->addr + entry->size < start)
            continue;           /* no overlap */

        top = max(entry->addr + entry->size, start + size);
        entry->addr = min(entry->addr, start);
        entry->size = top - entry->addr;

        return;
    }

    if (boot_mem_map.nr_map == BOOT_MEM_MAP_MAX) {
        pr_err("Ooops! Too many entries in the memory map!\n");
        return;
    }

    boot_mem_map.map[x].addr = start;
    boot_mem_map.map[x].size = size;
    boot_mem_map.map[x].type = type;
    boot_mem_map.nr_map++;
}

static void __init print_memory_map(void)
{
    int i;
    const int field = 2 * sizeof(unsigned long);

    for (i = 0; i < boot_mem_map.nr_map; i++) {
        printk(KERN_INFO " memory: %0*Lx @ %0*Lx ",
               field, (unsigned long long) boot_mem_map.map[i].size,
               field, (unsigned long long) boot_mem_map.map[i].addr);

        switch (boot_mem_map.map[i].type) {
        case BOOT_MEM_RAM:
            printk(KERN_CONT "(usable)\n");
            break;
        case BOOT_MEM_INIT_RAM:
            printk(KERN_CONT "(usable after init)\n");
            break;
        case BOOT_MEM_ROM_DATA:
            printk(KERN_CONT "(ROM data)\n");
            break;
        case BOOT_MEM_RESERVED:
            printk(KERN_CONT "(reserved)\n");
            break;
        default:
            printk(KERN_CONT "type %lu\n", boot_mem_map.map[i].type);
            break;
        }
    }
}

/*
 * Manage initrd
 */
#ifdef CONFIG_BLK_DEV_INITRD

static int __init rd_start_early(char *p)
{
    unsigned long start = memparse(p, &p);

#ifdef CONFIG_64BIT
    /* Guess if the sign extension was forgotten by bootloader */
    if (start < XKPHYS)
        start = (int)start;
#endif
    initrd_start = start;
    initrd_end += start;
    return 0;
}
early_param("rd_start", rd_start_early);

static int __init rd_size_early(char *p)
{
    initrd_end += memparse(p, &p);
    return 0;
}
early_param("rd_size", rd_size_early);

/* it returns the next free pfn after initrd */
static unsigned long __init init_initrd(void)
{
    unsigned long end;

    /*
     * Board specific code or command line parser should have
     * already set up initrd_start and initrd_end. In these cases
     * perfom sanity checks and use them if all looks good.
     */
    if (!initrd_start || initrd_end <= initrd_start)
        goto disable;

    if (initrd_start & ~PAGE_MASK) {
        pr_err("initrd start must be page aligned\n");
        goto disable;
    }
    if (initrd_start < PAGE_OFFSET) {
        pr_err("initrd start < PAGE_OFFSET\n");
        goto disable;
    }

    /*
     * Sanitize initrd addresses. For example firmware
     * can't guess if they need to pass them through
     * 64-bits values if the kernel has been built in pure
     * 32-bit. We need also to switch from KSEG0 to XKPHYS
     * addresses now, so the code can now safely use __pa().
     */
    end = __pa(initrd_end);
    initrd_end = (unsigned long)__va(end);
    initrd_start = (unsigned long)__va(__pa(initrd_start));

    ROOT_DEV = Root_RAM0;
    return PFN_UP(end);
disable:
    initrd_start = 0;
    initrd_end = 0;
    return 0;
}

static void __init finalize_initrd(void)
{
    unsigned long size = initrd_end - initrd_start;

    if (size == 0) {
        printk(KERN_INFO "Initrd not found or empty");
        goto disable;
    }
    if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) {
        printk(KERN_ERR "Initrd extends beyond end of memory");
        goto disable;
    }

    reserve_bootmem(__pa(initrd_start), size, BOOTMEM_DEFAULT);
    initrd_below_start_ok = 1;

    pr_info("Initial ramdisk at: 0x%lx (%lu bytes)\n",
        initrd_start, size);
    return;
disable:
    printk(KERN_CONT " - disabling initrd\n");
    initrd_start = 0;
    initrd_end = 0;
}

#else  /* !CONFIG_BLK_DEV_INITRD */

static unsigned long __init init_initrd(void)
{
    return 0;
}

#define finalize_initrd()   do {} while (0)

#endif

/*
 * Initialize the bootmem allocator. It also setup initrd related data
 * if needed.
 */
#ifdef CONFIG_SGI_IP27

static void __init bootmem_init(void)
{
    init_initrd();
    finalize_initrd();
}

#else  /* !CONFIG_SGI_IP27 */

static void __init bootmem_init(void)
{
    unsigned long reserved_end;
    unsigned long mapstart = ~0UL;
    unsigned long bootmap_size;
    int i;

    /*
     * Init any data related to initrd. It's a nop if INITRD is
     * not selected. Once that done we can determine the low bound
     * of usable memory.
     */
    reserved_end = max(init_initrd(),
               (unsigned long) PFN_UP(__pa_symbol(&_end)));

    /*
     * max_low_pfn is not a number of pages. The number of pages
     * of the system is given by 'max_low_pfn - min_low_pfn'.
     */
    min_low_pfn = ~0UL;
    max_low_pfn = 0;

    /*
     * Find the highest page frame number we have available.
     */
    for (i = 0; i < boot_mem_map.nr_map; i++) {
        unsigned long start, end;

        if (boot_mem_map.map[i].type != BOOT_MEM_RAM)
            continue;

        start = PFN_UP(boot_mem_map.map[i].addr);
        end = PFN_DOWN(boot_mem_map.map[i].addr
                + boot_mem_map.map[i].size);

        if (end > max_low_pfn)
            max_low_pfn = end;
        if (start < min_low_pfn)
            min_low_pfn = start;
        if (end <= reserved_end)
            continue;
        if (start >= mapstart)
            continue;
        mapstart = max(reserved_end, start);
    }

    if (min_low_pfn >= max_low_pfn)
        panic("Incorrect memory mapping !!!");
    if (min_low_pfn > ARCH_PFN_OFFSET) {
        pr_info("Wasting %lu bytes for tracking %lu unused pages\n",
            (min_low_pfn - ARCH_PFN_OFFSET) * sizeof(struct page),
            min_low_pfn - ARCH_PFN_OFFSET);
    } else if (min_low_pfn < ARCH_PFN_OFFSET) {
        pr_info("%lu free pages won't be used\n",
            ARCH_PFN_OFFSET - min_low_pfn);
    }
    min_low_pfn = ARCH_PFN_OFFSET;

    /*
     * Determine low and high memory ranges
     */
    max_pfn = max_low_pfn;
    if (max_low_pfn > PFN_DOWN(HIGHMEM_START)) {
#ifdef CONFIG_HIGHMEM
        highstart_pfn = PFN_DOWN(HIGHMEM_START);
        highend_pfn = max_low_pfn;
#endif
        max_low_pfn = PFN_DOWN(HIGHMEM_START);
    }

    /*
     * Initialize the boot-time allocator with low memory only.
     */
    bootmap_size = init_bootmem_node(NODE_DATA(0), mapstart,
                     min_low_pfn, max_low_pfn);


    for (i = 0; i < boot_mem_map.nr_map; i++) {
        unsigned long start, end;

        start = PFN_UP(boot_mem_map.map[i].addr);
        end = PFN_DOWN(boot_mem_map.map[i].addr
                + boot_mem_map.map[i].size);

        if (start <= min_low_pfn)
            start = min_low_pfn;
        if (start >= end)
            continue;

#ifndef CONFIG_HIGHMEM
        if (end > max_low_pfn)
            end = max_low_pfn;

        /*
         * ... finally, is the area going away?
         */
        if (end <= start)
            continue;
#endif

        memblock_add_node(PFN_PHYS(start), PFN_PHYS(end - start), 0);
    }

    /*
     * Register fully available low RAM pages with the bootmem allocator.
     */
    for (i = 0; i < boot_mem_map.nr_map; i++) {
        unsigned long start, end, size;

        start = PFN_UP(boot_mem_map.map[i].addr);
        end   = PFN_DOWN(boot_mem_map.map[i].addr
                    + boot_mem_map.map[i].size);

        /*
         * Reserve usable memory.
         */
        switch (boot_mem_map.map[i].type) {
        case BOOT_MEM_RAM:
            break;
        case BOOT_MEM_INIT_RAM:
            memory_present(0, start, end);
            continue;
        default:
            /* Not usable memory */
            continue;
        }

        /*
         * We are rounding up the start address of usable memory
         * and at the end of the usable range downwards.
         */
        if (start >= max_low_pfn)
            continue;
        if (start < reserved_end)
            start = reserved_end;
        if (end > max_low_pfn)
            end = max_low_pfn;

        /*
         * ... finally, is the area going away?
         */
        if (end <= start)
            continue;
        size = end - start;

        /* Register lowmem ranges */
        free_bootmem(PFN_PHYS(start), size << PAGE_SHIFT);
        memory_present(0, start, end);
    }

    /*
     * Reserve the bootmap memory.
     */
    reserve_bootmem(PFN_PHYS(mapstart), bootmap_size, BOOTMEM_DEFAULT);

    /*
     * Reserve initrd memory if needed.
     */
    finalize_initrd();
}

#endif  /* CONFIG_SGI_IP27 */

/*
 * arch_mem_init - initialize memory management subsystem
 *
 *  o plat_mem_setup() detects the memory configuration and will record detected
 *    memory areas using add_memory_region.
 *
 * At this stage the memory configuration of the system is known to the
 * kernel but generic memory management system is still entirely uninitialized.
 *
 *  o bootmem_init()
 *  o sparse_init()
 *  o paging_init()
 *
 * At this stage the bootmem allocator is ready to use.
 *
 * NOTE: historically plat_mem_setup did the entire platform initialization.
 *       This was rather impractical because it meant plat_mem_setup had to
 * get away without any kind of memory allocator.  To keep old code from
 * breaking plat_setup was just renamed to plat_setup and a second platform
 * initialization hook for anything else was introduced.
 */

static int usermem __initdata;

static int __init early_parse_mem(char *p)
{
    unsigned long start, size;

    /*
     * If a user specifies memory size, we
     * blow away any automatically generated
     * size.
     */
    if (usermem == 0) {
        boot_mem_map.nr_map = 0;
        usermem = 1;
    }
    start = 0;
    size = memparse(p, &p);
    if (*p == '@')
        start = memparse(p + 1, &p);

    add_memory_region(start, size, BOOT_MEM_RAM);
    return 0;
}
early_param("mem", early_parse_mem);

static void __init arch_mem_init(char **cmdline_p)
{
    phys_t init_mem, init_end, init_size;

    extern void plat_mem_setup(void);

    /* call board setup routine */
    plat_mem_setup();

    init_mem = PFN_UP(__pa_symbol(&__init_begin)) << PAGE_SHIFT;
    init_end = PFN_DOWN(__pa_symbol(&__init_end)) << PAGE_SHIFT;
    init_size = init_end - init_mem;
    if (init_size) {
        /* Make sure it is in the boot_mem_map */
        int i, found;
        found = 0;
        for (i = 0; i < boot_mem_map.nr_map; i++) {
            if (init_mem >= boot_mem_map.map[i].addr &&
                init_mem < (boot_mem_map.map[i].addr +
                    boot_mem_map.map[i].size)) {
                found = 1;
                break;
            }
        }
        if (!found)
            add_memory_region(init_mem, init_size,
                      BOOT_MEM_INIT_RAM);
    }

    pr_info("Determined physical RAM map:\n");
    print_memory_map();

#ifdef CONFIG_CMDLINE_BOOL
#ifdef CONFIG_CMDLINE_OVERRIDE
    strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
#else
    if (builtin_cmdline[0]) {
        strlcat(arcs_cmdline, " ", COMMAND_LINE_SIZE);
        strlcat(arcs_cmdline, builtin_cmdline, COMMAND_LINE_SIZE);
    }
    strlcpy(boot_command_line, arcs_cmdline, COMMAND_LINE_SIZE);
#endif
#else
    strlcpy(boot_command_line, arcs_cmdline, COMMAND_LINE_SIZE);
#endif
    strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);

    *cmdline_p = command_line;

    parse_early_param();

    if (usermem) {
        pr_info("User-defined physical RAM map:\n");
        print_memory_map();
    }

    bootmem_init();
    device_tree_init();
    sparse_init();
    plat_swiotlb_setup();
    paging_init();
}

static void __init resource_init(void)
{
    int i;

    if (UNCAC_BASE != IO_BASE)
        return;

    code_resource.start = __pa_symbol(&_text);
    code_resource.end = __pa_symbol(&_etext) - 1;
    data_resource.start = __pa_symbol(&_etext);
    data_resource.end = __pa_symbol(&_edata) - 1;

    /*
     * Request address space for all standard RAM.
     */
    for (i = 0; i < boot_mem_map.nr_map; i++) {
        struct resource *res;
        unsigned long start, end;

        start = boot_mem_map.map[i].addr;
        end = boot_mem_map.map[i].addr + boot_mem_map.map[i].size - 1;
        if (start >= HIGHMEM_START)
            continue;
        if (end >= HIGHMEM_START)
            end = HIGHMEM_START - 1;

        res = alloc_bootmem(sizeof(struct resource));
        switch (boot_mem_map.map[i].type) {
        case BOOT_MEM_RAM:
        case BOOT_MEM_INIT_RAM:
        case BOOT_MEM_ROM_DATA:
            res->name = "System RAM";
            break;
        case BOOT_MEM_RESERVED:
        default:
            res->name = "reserved";
        }

        res->start = start;
        res->end = end;

        res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
        request_resource(&iomem_resource, res);

        /*
         *  We don't know which RAM region contains kernel data,
         *  so we try it repeatedly and let the resource manager
         *  test it.
         */
        request_resource(res, &code_resource);
        request_resource(res, &data_resource);
    }
}

void __init setup_arch(char **cmdline_p)
{
    cpu_probe();
    prom_init();

#ifdef CONFIG_EARLY_PRINTK
    setup_early_printk();
#endif
    cpu_report();
    check_bugs_early();

#if defined(CONFIG_VT)
#if defined(CONFIG_VGA_CONSOLE)
    conswitchp = &vga_con;
#elif defined(CONFIG_DUMMY_CONSOLE)
    conswitchp = &dummy_con;
#endif
#endif

    arch_mem_init(cmdline_p);

    resource_init();
    plat_smp_setup();

    cpu_cache_init();
}

unsigned long kernelsp[NR_CPUS];
unsigned long fw_arg0, fw_arg1, fw_arg2, fw_arg3;

#ifdef CONFIG_DEBUG_FS
struct dentry *mips_debugfs_dir;
static int __init debugfs_mips(void)
{
    struct dentry *d;

    d = debugfs_create_dir("mips", NULL);
    if (!d)
        return -ENOMEM;
    mips_debugfs_dir = d;
    return 0;
}
arch_initcall(debugfs_mips);
#endif