/*
 *  linux/init/main.c
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 *
 *  GK 2/5/95  -  Changed to support mounting root fs via NFS
 *  Added initrd & change_root: Werner Almesberger & Hans Lermen, Feb '96
 *  Moan early if gcc is old, avoiding bogus kernels - Paul Gortmaker, May '96
 *  Simplified starting of init:  Michael A. Griffith <grif@acm.org> 
 */

#define __KERNEL_SYSCALLS__

#include <linux/config.h>
#include <linux/proc_fs.h>
#include <linux/devfs_fs_kernel.h>
#include <linux/unistd.h>
#include <linux/string.h>
#include <linux/ctype.h>
#include <linux/delay.h>
#include <linux/utsname.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/smp_lock.h>
#include <linux/blk.h>
#include <linux/hdreg.h>
#include <linux/iobuf.h>
#include <linux/bootmem.h>
#include <linux/tty.h>

#include <asm/io.h>
#include <asm/bugs.h>

#if defined(CONFIG_ARCH_S390)
#include <asm/s390mach.h>
#include <asm/ccwcache.h>
#endif

#ifdef CONFIG_PCI
#include <linux/pci.h>
#endif

#ifdef CONFIG_DIO
#include <linux/dio.h>
#endif

#ifdef CONFIG_ZORRO
#include <linux/zorro.h>
#endif

#ifdef CONFIG_MTRR
#  include <asm/mtrr.h>
#endif

#ifdef CONFIG_NUBUS
#include <linux/nubus.h>
#endif

#ifdef CONFIG_ISAPNP
#include <linux/isapnp.h>
#endif

#ifdef CONFIG_IRDA
extern int irda_proto_init(void);
extern int irda_device_init(void);
#endif

#ifdef CONFIG_X86_LOCAL_APIC
#include <asm/smp.h>
#endif

/*
 * Versions of gcc older than that listed below may actually compile
 * and link okay, but the end product can have subtle run time bugs.
 * To avoid associated bogus bug reports, we flatly refuse to compile
 * with a gcc that is known to be too old from the very beginning.
 */
#if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 91)
#error Sorry, your GCC is too old. It builds incorrect kernels.
#endif

extern char _stext, _etext;
extern char *linux_banner;

static int init(void *);

extern void init_IRQ(void);
extern void init_modules(void);
extern void sock_init(void);
extern void fork_init(unsigned long);
extern void mca_init(void);
extern void sbus_init(void);
extern void ppc_init(void);
extern void sysctl_init(void);
extern void signals_init(void);
extern int init_pcmcia_ds(void);

extern void free_initmem(void);

#ifdef CONFIG_TC
extern void tc_init(void);
#endif

extern void ecard_init(void);

#if defined(CONFIG_SYSVIPC)
extern void ipc_init(void);
#endif
#ifdef CONFIG_PERFMON
extern void perfmon_init(void);
#endif

/*
 * Boot command-line arguments
 */
#define MAX_INIT_ARGS 8
#define MAX_INIT_ENVS 8

extern void time_init(void);
extern void softirq_init(void);

int rows, cols;

#ifdef CONFIG_BLK_DEV_INITRD
unsigned int real_root_dev;     /* do_proc_dointvec cannot handle kdev_t */
#endif

int root_mountflags = MS_RDONLY;
char *execute_command;
char root_device_name[64];


static char * argv_init[MAX_INIT_ARGS+2] = { "init", NULL, };
static char * envp_init[MAX_INIT_ENVS+2] = { "HOME=/", "TERM=linux", NULL, };

static int __init profile_setup(char *str)
{
    int par;
    if (get_option(&str,&par)) prof_shift = par;
        return 1;
}

__setup("profile=", profile_setup);


static struct dev_name_struct {
        const char *name;
        const int num;
} root_dev_names[] __initdata = {
        { "nfs",     0x00ff },
        { "hda",     0x0300 },
        { "hdb",     0x0340 },
        { "loop",    0x0700 },
        { "hdc",     0x1600 },
        { "hdd",     0x1640 },
        { "hde",     0x2100 },
        { "hdf",     0x2140 },
        { "hdg",     0x2200 },
        { "hdh",     0x2240 },
        { "hdi",     0x3800 },
        { "hdj",     0x3840 },
        { "hdk",     0x3900 },
        { "hdl",     0x3940 },
        { "hdm",     0x5800 },
        { "hdn",     0x5840 },
        { "hdo",     0x5900 },
        { "hdp",     0x5940 },
        { "hdq",     0x5A00 },
        { "hdr",     0x5A40 },
        { "hds",     0x5B00 },
        { "hdt",     0x5B40 },
        { "sda",     0x0800 },
        { "sdb",     0x0810 },
        { "sdc",     0x0820 },
        { "sdd",     0x0830 },
        { "sde",     0x0840 },
        { "sdf",     0x0850 },
        { "sdg",     0x0860 },
        { "sdh",     0x0870 },
        { "sdi",     0x0880 },
        { "sdj",     0x0890 },
        { "sdk",     0x08a0 },
        { "sdl",     0x08b0 },
        { "sdm",     0x08c0 },
        { "sdn",     0x08d0 },
        { "sdo",     0x08e0 },
        { "sdp",     0x08f0 },
        { "ada",     0x1c00 },
        { "adb",     0x1c10 },
        { "adc",     0x1c20 },
        { "add",     0x1c30 },
        { "ade",     0x1c40 },
        { "fd",      0x0200 },
        { "md",      0x0900 },       
        { "xda",     0x0d00 },
        { "xdb",     0x0d40 },
        { "ram",     0x0100 },
        { "scd",     0x0b00 },
        { "mcd",     0x1700 },
        { "cdu535",  0x1800 },
        { "sonycd",  0x1800 },
        { "aztcd",   0x1d00 },
        { "cm206cd", 0x2000 },
        { "gscd",    0x1000 },
        { "sbpcd",   0x1900 },
        { "eda",     0x2400 },
        { "edb",     0x2440 },
        { "pda",        0x2d00 },
        { "pdb",        0x2d10 },
        { "pdc",        0x2d20 },
        { "pdd",        0x2d30 },
        { "pcd",        0x2e00 },
        { "pf",         0x2f00 },
        { "apblock", APBLOCK_MAJOR << 8},
        { "ddv", DDV_MAJOR << 8},
        { "jsfd",    JSFD_MAJOR << 8},
#if defined(CONFIG_ARCH_S390)
        { "dasda", (DASD_MAJOR << MINORBITS) },
        { "dasdb", (DASD_MAJOR << MINORBITS) + (1 << 2) },
        { "dasdc", (DASD_MAJOR << MINORBITS) + (2 << 2) },
        { "dasdd", (DASD_MAJOR << MINORBITS) + (3 << 2) },
        { "dasde", (DASD_MAJOR << MINORBITS) + (4 << 2) },
        { "dasdf", (DASD_MAJOR << MINORBITS) + (5 << 2) },
        { "dasdg", (DASD_MAJOR << MINORBITS) + (6 << 2) },
        { "dasdh", (DASD_MAJOR << MINORBITS) + (7 << 2) },
#endif
#if defined(CONFIG_BLK_CPQ_DA) || defined(CONFIG_BLK_CPQ_DA_MODULE)
        { "ida/c0d0p",0x4800 },
        { "ida/c0d1p",0x4810 },
        { "ida/c0d2p",0x4820 },
        { "ida/c0d3p",0x4830 },
        { "ida/c0d4p",0x4840 },
        { "ida/c0d5p",0x4850 },
        { "ida/c0d6p",0x4860 },
        { "ida/c0d7p",0x4870 },
        { "ida/c0d8p",0x4880 },
        { "ida/c0d9p",0x4890 },
        { "ida/c0d10p",0x48A0 },
        { "ida/c0d11p",0x48B0 },
        { "ida/c0d12p",0x48C0 },
        { "ida/c0d13p",0x48D0 },
        { "ida/c0d14p",0x48E0 },
        { "ida/c0d15p",0x48F0 },
#endif
#if defined(CONFIG_BLK_CPQ_CISS_DA) || defined(CONFIG_BLK_CPQ_CISS_DA_MODULE)
        { "cciss/c0d0p",0x6800 },
        { "cciss/c0d1p",0x6810 },
        { "cciss/c0d2p",0x6820 },
        { "cciss/c0d3p",0x6830 },
        { "cciss/c0d4p",0x6840 },
        { "cciss/c0d5p",0x6850 },
        { "cciss/c0d6p",0x6860 },
        { "cciss/c0d7p",0x6870 },
        { "cciss/c0d8p",0x6880 },
        { "cciss/c0d9p",0x6890 },
        { "cciss/c0d10p",0x68A0 },
        { "cciss/c0d11p",0x68B0 },
        { "cciss/c0d12p",0x68C0 },
        { "cciss/c0d13p",0x68D0 },
        { "cciss/c0d14p",0x68E0 },
        { "cciss/c0d15p",0x68F0 },
#endif
        { "nftla", 0x5d00 },
        { "nftlb", 0x5d10 },
        { "nftlc", 0x5d20 },
        { "nftld", 0x5d30 },
        { "ftla", 0x2c00 },
        { "ftlb", 0x2c08 },
        { "ftlc", 0x2c10 },
        { "ftld", 0x2c18 },
        { "mtdblock", 0x1f00 },
        { NULL, 0 }
};

kdev_t __init name_to_kdev_t(char *line)
{
        int base = 0;

        if (strncmp(line,"/dev/",5) == 0) {
                struct dev_name_struct *dev = root_dev_names;
                line += 5;
                do {
                        int len = strlen(dev->name);
                        if (strncmp(line,dev->name,len) == 0) {
                                line += len;
                                base = dev->num;
                                break;
                        }
                        dev++;
                } while (dev->name);
        }
        return to_kdev_t(base + simple_strtoul(line,NULL,base?10:16));
}

static int __init root_dev_setup(char *line)
{
        int i;
        char ch;

        ROOT_DEV = name_to_kdev_t(line);
        memset (root_device_name, 0, sizeof root_device_name);
        if (strncmp (line, "/dev/", 5) == 0) line += 5;
        for (i = 0; i < sizeof root_device_name - 1; ++i)
        {
            ch = line[i];
            if ( isspace (ch) || (ch == ',') || (ch == '\0') ) break;
            root_device_name[i] = ch;
        }
        return 1;
}

__setup("root=", root_dev_setup);

static int __init checksetup(char *line)
{
        struct kernel_param *p;

        p = &__setup_start;
        do {
                int n = strlen(p->str);
                if (!strncmp(line,p->str,n)) {
                        if (p->setup_func(line+n))
                                return 1;
                }
                p++;
        } while (p < &__setup_end);
        return 0;
}

/* this should be approx 2 Bo*oMips to start (note initial shift), and will
   still work even if initially too large, it will just take slightly longer */
unsigned long loops_per_jiffy = (1<<12);

/* This is the number of bits of precision for the loops_per_jiffy.  Each
   bit takes on average 1.5/HZ seconds.  This (like the original) is a little
   better than 1% */
#define LPS_PREC 8

void __init calibrate_delay(void)
{
        unsigned long ticks, loopbit;
        int lps_precision = LPS_PREC;

        loops_per_jiffy = (1<<12);

        printk("Calibrating delay loop... ");
        while (loops_per_jiffy <<= 1) {
                /* wait for "start of" clock tick */
                ticks = jiffies;
                while (ticks == jiffies)
                        /* nothing */;
                /* Go .. */
                ticks = jiffies;
                __delay(loops_per_jiffy);
                ticks = jiffies - ticks;
                if (ticks)
                        break;
        }

/* Do a binary approximation to get loops_per_jiffy set to equal one clock
   (up to lps_precision bits) */
        loops_per_jiffy >>= 1;
        loopbit = loops_per_jiffy;
        while ( lps_precision-- && (loopbit >>= 1) ) {
                loops_per_jiffy |= loopbit;
                ticks = jiffies;
                while (ticks == jiffies);
                ticks = jiffies;
                __delay(loops_per_jiffy);
                if (jiffies != ticks)   /* longer than 1 tick */
                        loops_per_jiffy &= ~loopbit;
        }

/* Round the value and print it */      
        printk("%lu.%02lu BogoMIPS\n",
                loops_per_jiffy/(500000/HZ),
                (loops_per_jiffy/(5000/HZ)) % 100);
}

static int __init readonly(char *str)
{
        if (*str)
                return 0;
        root_mountflags |= MS_RDONLY;
        return 1;
}

static int __init readwrite(char *str)
{
        if (*str)
                return 0;
        root_mountflags &= ~MS_RDONLY;
        return 1;
}

static int __init debug_kernel(char *str)
{
        if (*str)
                return 0;
        console_loglevel = 10;
        return 1;
}

static int __init quiet_kernel(char *str)
{
        if (*str)
                return 0;
        console_loglevel = 4;
        return 1;
}

__setup("ro", readonly);
__setup("rw", readwrite);
__setup("debug", debug_kernel);
__setup("quiet", quiet_kernel);

/*
 * This is a simple kernel command line parsing function: it parses
 * the command line, and fills in the arguments/environment to init
 * as appropriate. Any cmd-line option is taken to be an environment
 * variable if it contains the character '='.
 *
 * This routine also checks for options meant for the kernel.
 * These options are not given to init - they are for internal kernel use only.
 */
static void __init parse_options(char *line)
{
        char *next,*quote;
        int args, envs;

        if (!*line)
                return;
        args = 0;
        envs = 1;       /* TERM is set to 'linux' by default */
        next = line;
        while ((line = next) != NULL) {
                quote = strchr(line,'"');
                next = strchr(line, ' ');
                while (next != NULL && quote != NULL && quote < next) {
                        /* we found a left quote before the next blank
                         * now we have to find the matching right quote
                         */
                        next = strchr(quote+1, '"');
                        if (next != NULL) {
                                quote = strchr(next+1, '"');
                                next = strchr(next+1, ' ');
                        }
                }
                if (next != NULL)
                        *next++ = 0;
                if (!strncmp(line,"init=",5)) {
                        line += 5;
                        execute_command = line;
                        /* In case LILO is going to boot us with default command line,
                         * it prepends "auto" before the whole cmdline which makes
                         * the shell think it should execute a script with such name.
                         * So we ignore all arguments entered _before_ init=... [MJ]
                         */
                        args = 0;
                        continue;
                }
                if (checksetup(line))
                        continue;
                
                /*
                 * Then check if it's an environment variable or
                 * an option.
                 */
                if (strchr(line,'=')) {
                        if (envs >= MAX_INIT_ENVS)
                                break;
                        envp_init[++envs] = line;
                } else {
                        if (args >= MAX_INIT_ARGS)
                                break;
                        if (*line)
                                argv_init[++args] = line;
                }
        }
        argv_init[args+1] = NULL;
        envp_init[envs+1] = NULL;
}


extern void setup_arch(char **);
extern void cpu_idle(void);

unsigned long wait_init_idle;

#ifndef CONFIG_SMP

#ifdef CONFIG_X86_LOCAL_APIC
static void __init smp_init(void)
{
        APIC_init_uniprocessor();
}
#else
#define smp_init()      do { } while (0)
#endif

#else


/* Called by boot processor to activate the rest. */
static void __init smp_init(void)
{
        /* Get other processors into their bootup holding patterns. */
        smp_boot_cpus();
        wait_init_idle = cpu_online_map;
        clear_bit(current->processor, &wait_init_idle); /* Don't wait on me! */

        smp_threads_ready=1;
        smp_commence();

        /* Wait for the other cpus to set up their idle processes */
        printk("Waiting on wait_init_idle (map = 0x%lx)\n", wait_init_idle);
        while (wait_init_idle) {
                cpu_relax();
                barrier();
        }
        printk("All processors have done init_idle\n");
}

#endif

/*
 * We need to finalize in a non-__init function or else race conditions
 * between the root thread and the init thread may cause start_kernel to
 * be reaped by free_initmem before the root thread has proceeded to
 * cpu_idle.
 */

static void rest_init(void)
{
        kernel_thread(init, NULL, CLONE_FS | CLONE_FILES | CLONE_SIGNAL);
        unlock_kernel();
        current->need_resched = 1;
        cpu_idle();
} 

/*
 *      Activate the first processor.
 */

asmlinkage void __init start_kernel(void)
{
        char * command_line;
        unsigned long mempages;
        extern char saved_command_line[];
/*
 * Interrupts are still disabled. Do necessary setups, then
 * enable them
 */
        lock_kernel();
        printk(linux_banner);
        setup_arch(&command_line);
        printk("Kernel command line: %s\n", saved_command_line);
        parse_options(command_line);
        trap_init();
        init_IRQ();
        sched_init();
        softirq_init();
        time_init();

        /*
         * HACK ALERT! This is early. We're enabling the console before
         * we've done PCI setups etc, and console_init() must be aware of
         * this. But we do want output early, in case something goes wrong.
         */
        console_init();
#ifdef CONFIG_MODULES
        init_modules();
#endif
        if (prof_shift) {
                unsigned int size;
                /* only text is profiled */
                prof_len = (unsigned long) &_etext - (unsigned long) &_stext;
                prof_len >>= prof_shift;
                
                size = prof_len * sizeof(unsigned int) + PAGE_SIZE-1;
                prof_buffer = (unsigned int *) alloc_bootmem(size);
        }

        kmem_cache_init();
        sti();
        calibrate_delay();
#ifdef CONFIG_BLK_DEV_INITRD
        if (initrd_start && !initrd_below_start_ok &&
                        initrd_start < min_low_pfn << PAGE_SHIFT) {
                printk(KERN_CRIT "initrd overwritten (0x%08lx < 0x%08lx) - "
                    "disabling it.\n",initrd_start,min_low_pfn << PAGE_SHIFT);
                initrd_start = 0;
        }
#endif
        mem_init();
        kmem_cache_sizes_init();
        pgtable_cache_init();

#ifdef CONFIG_PERFMON
        perfmon_init();
#endif
        mempages = num_physpages;

        fork_init(mempages);
        proc_caches_init();
        vfs_caches_init(mempages);
        buffer_init(mempages);
        page_cache_init(mempages);
#if defined(CONFIG_ARCH_S390)
        ccwcache_init();
#endif
        signals_init();
#ifdef CONFIG_PROC_FS
        proc_root_init();
#endif
#if defined(CONFIG_SYSVIPC)
        ipc_init();
#endif
        check_bugs();
        printk("POSIX conformance testing by UNIFIX\n");

        /* 
         *      We count on the initial thread going ok 
         *      Like idlers init is an unlocked kernel thread, which will
         *      make syscalls (and thus be locked).
         */
        smp_init();
        rest_init();
}

#ifdef CONFIG_BLK_DEV_INITRD
static int do_linuxrc(void * shell)
{
        static char *argv[] = { "linuxrc", NULL, };

        close(0);close(1);close(2);
        setsid();
        (void) open("/dev/console",O_RDWR,0);
        (void) dup(0);
        (void) dup(0);
        return execve(shell, argv, envp_init);
}

#endif

struct task_struct *child_reaper = &init_task;

static void __init do_initcalls(void)
{
        initcall_t *call;

        call = &__initcall_start;
        do {
                (*call)();
                call++;
        } while (call < &__initcall_end);

        /* Make sure there is no pending stuff from the initcall sequence */
        flush_scheduled_tasks();
}

/*
 * Ok, the machine is now initialized. None of the devices
 * have been touched yet, but the CPU subsystem is up and
 * running, and memory and process management works.
 *
 * Now we can finally start doing some real work..
 */
static void __init do_basic_setup(void)
{

        /*
         * Tell the world that we're going to be the grim
         * reaper of innocent orphaned children.
         *
         * We don't want people to have to make incorrect
         * assumptions about where in the task array this
         * can be found.
         */
        child_reaper = current;

#if defined(CONFIG_MTRR)        /* Do this after SMP initialization */
/*
 * We should probably create some architecture-dependent "fixup after
 * everything is up" style function where this would belong better
 * than in init/main.c..
 */
        mtrr_init();
#endif

#ifdef CONFIG_SYSCTL
        sysctl_init();
#endif

        /*
         * Ok, at this point all CPU's should be initialized, so
         * we can start looking into devices..
         */
#if defined(CONFIG_ARCH_S390)
        s390_init_machine_check();
#endif

#ifdef CONFIG_PCI
        pci_init();
#endif
#ifdef CONFIG_SBUS
        sbus_init();
#endif
#if defined(CONFIG_PPC)
        ppc_init();
#endif
#ifdef CONFIG_MCA
        mca_init();
#endif
#ifdef CONFIG_ARCH_ACORN
        ecard_init();
#endif
#ifdef CONFIG_ZORRO
        zorro_init();
#endif
#ifdef CONFIG_DIO
        dio_init();
#endif
#ifdef CONFIG_NUBUS
        nubus_init();
#endif
#ifdef CONFIG_ISAPNP
        isapnp_init();
#endif
#ifdef CONFIG_TC
        tc_init();
#endif

        /* Networking initialization needs a process context */ 
        sock_init();

        start_context_thread();
        do_initcalls();

#ifdef CONFIG_IRDA
        irda_proto_init();
        irda_device_init(); /* Must be done after protocol initialization */
#endif
#ifdef CONFIG_PCMCIA
        init_pcmcia_ds();               /* Do this last */
#endif
}

extern void rd_load(void);
extern void initrd_load(void);

/*
 * Prepare the namespace - decide what/where to mount, load ramdisks, etc.
 */
static void prepare_namespace(void)
{
#ifdef CONFIG_BLK_DEV_INITRD
        int real_root_mountflags = root_mountflags;
        if (!initrd_start)
                mount_initrd = 0;
        if (mount_initrd)
                root_mountflags &= ~MS_RDONLY;
        real_root_dev = ROOT_DEV;
#endif

#ifdef CONFIG_BLK_DEV_RAM
#ifdef CONFIG_BLK_DEV_INITRD
        if (mount_initrd)
                initrd_load();
        else
#endif
        rd_load();
#endif

        /* Mount the root filesystem.. */
        mount_root();

        mount_devfs_fs ();

#ifdef CONFIG_BLK_DEV_INITRD
        root_mountflags = real_root_mountflags;
        if (mount_initrd && ROOT_DEV != real_root_dev
            && MAJOR(ROOT_DEV) == RAMDISK_MAJOR && MINOR(ROOT_DEV) == 0) {
                int error;
                int i, pid;

                pid = kernel_thread(do_linuxrc, "/linuxrc", SIGCHLD);
                if (pid > 0) {
                        while (pid != wait(&i)) {
                                current->policy |= SCHED_YIELD;
                                schedule();
                        }
                }
                if (MAJOR(real_root_dev) != RAMDISK_MAJOR
                     || MINOR(real_root_dev) != 0) {
                        error = change_root(real_root_dev,"/initrd");
                        if (error)
                                printk(KERN_ERR "Change root to /initrd: "
                                    "error %d\n",error);
                }
        }
#endif
}

static int init(void * unused)
{
        lock_kernel();
        do_basic_setup();

        prepare_namespace();

        /*
         * Ok, we have completed the initial bootup, and
         * we're essentially up and running. Get rid of the
         * initmem segments and start the user-mode stuff..
         */
        free_initmem();
        unlock_kernel();

        if (open("/dev/console", O_RDWR, 0) < 0)
                printk("Warning: unable to open an initial console.\n");

        (void) dup(0);
        (void) dup(0);
        
        /*
         * We try each of these until one succeeds.
         *
         * The Bourne shell can be used instead of init if we are 
         * trying to recover a really broken machine.
         */

        if (execute_command)
                execve(execute_command,argv_init,envp_init);
        execve("/sbin/init",argv_init,envp_init);
        execve("/etc/init",argv_init,envp_init);
        execve("/bin/init",argv_init,envp_init);
        execve("/bin/sh",argv_init,envp_init);
        panic("No init found.  Try passing init= option to kernel.");
}