boot.h

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/*      boot.h - Info between different parts of boot.  Author: Kees J. Bot
 */

#ifndef DEBUG
#define DEBUG 0
#endif

/* Constants describing the metal: */

#define SECTOR_SIZE     512
#define SECTOR_SHIFT    9
#define RATIO(b)                ((b) / SECTOR_SIZE)

#define PARAMSEC        1       /* Sector containing boot parameters. */

#define DSKBASE         0x1E    /* Floppy disk parameter vector. */
#define DSKPARSIZE      11      /* There are this many bytes of parameters. */

#define ESC             '\33'   /* Escape key. */

#define HEADERPOS      0x00600L /* Place for an array of struct exec's. */

#define FREEPOS        0x08000L /* Memory from FREEPOS to caddr is free to
                                 * play with.
                                 */
#if BIOS
#define MSEC_PER_TICK     55    /* Clock does 18.2 ticks per second. */
#define TICKS_PER_DAY 0x1800B0L /* After 24 hours it wraps. */
#endif

#if UNIX
#define MSEC_PER_TICK   1000    /* Clock does 18.2 ticks per second. */
#define TICKS_PER_DAY  86400L   /* Doesn't wrap, but that doesn't matter. */
#endif

#define BOOTPOS        0x07C00L /* Bootstraps are loaded here. */
#define SIGNATURE       0xAA55  /* Proper bootstraps have this signature. */
#define SIGNATOFF       510     /* Offset within bootblock. */

/* BIOS video modes. */
#define MONO_MODE       0x07    /* 80x25 monochrome. */
#define COLOR_MODE      0x03    /* 80x25 color. */


/* Variables shared with boothead.s: */
#ifndef EXTERN
#define EXTERN extern
#endif

typedef struct vector {         /* 8086 vector */
        u16_t   offset;
        u16_t   segment;
} vector;

EXTERN vector rem_part;         /* Boot partition table entry. */

EXTERN u32_t caddr, daddr;      /* Code and data address of the boot program. */
EXTERN u32_t runsize;           /* Size of this program. */

EXTERN u16_t device;            /* Drive being booted from. */

typedef struct {                /* One chunk of free memory. */
        u32_t   base;           /* Start byte. */
        u32_t   size;           /* Number of bytes. */
} memory;

EXTERN memory mem[3];           /* List of available memory. */
EXTERN int mon_return;          /* Monitor stays in memory? */

typedef struct bios_env
{
        u16_t ax;
        u16_t bx;
        u16_t cx;
        u16_t flags;
} bios_env_t;

#define FL_CARRY        0x0001  /* carry flag */

/* Functions defined by boothead.s: */

void exit(int code);
                        /* Exit the monitor. */
u32_t mon2abs(void *ptr);
                        /* Local monitor address to absolute address. */
u32_t vec2abs(vector *vec);
                        /* Vector to absolute address. */
void raw_copy(u32_t dstaddr, u32_t srcaddr, u32_t count);
                        /* Copy bytes from anywhere to anywhere. */
u16_t get_word(u32_t addr);
                        /* Get a word from anywhere. */
void put_word(u32_t addr, U16_t word);
                        /* Put a word anywhere. */
void relocate(void);
                        /* Switch to a copy of this program. */
int dev_open(void), dev_close(void);
                        /* Open device and determine params / close device. */
int dev_boundary(u32_t sector);
                        /* True if sector is on a track boundary. */
int readsectors(u32_t bufaddr, u32_t sector, U8_t count);
                        /* Read 1 or more sectors from "device". */
int writesectors(u32_t bufaddr, u32_t sector, U8_t count);
                        /* Write 1 or more sectors to "device". */
int getch(void);
                        /* Read a keypress. */
void scan_keyboard(void);       
                        /* Read keypress directly from kb controller. */
void ungetch(int c);
                        /* Undo a keypress. */
int escape(void);
                        /* True if escape typed. */
void putch(int c);
                        /* Send a character to the screen. */
#if BIOS
void pause(void);
                        /* Wait for an interrupt. */
void serial_init(int line);
#endif                  /* Enable copying console I/O to a serial line. */

void set_mode(unsigned mode);
void clear_screen(void);
                        /* Set video mode / clear the screen. */

u16_t get_bus(void);
                        /* System bus type, XT, AT, or MCA. */
u16_t get_video(void);
                        /* Display type, MDA to VGA. */
u32_t get_tick(void);
                        /* Current value of the clock tick counter. */

void bootstrap(int device, struct part_entry *entry);
                        /* Execute a bootstrap routine for a different O.S. */
void minix(u32_t koff, u32_t kcs, u32_t kds,
                                char *bootparams, size_t paramsize, u32_t aout);
                        /* Start Minix. */
void int15(bios_env_t *);


/* Shared between boot.c and bootimage.c: */

/* Sticky attributes. */
#define E_SPECIAL       0x01    /* These are known to the program. */
#define E_DEV           0x02    /* The value is a device name. */
#define E_RESERVED      0x04    /* May not be set by user, e.g. 'boot' */
#define E_STICKY        0x07    /* Don't go once set. */

/* Volatile attributes. */
#define E_VAR           0x08    /* Variable */
#define E_FUNCTION      0x10    /* Function definition. */

/* Variables, functions, and commands. */
typedef struct environment {
        struct environment *next;
        char    flags;
        char    *name;          /* name = value */
        char    *arg;           /* name(arg) {value} */
        char    *value;
        char    *defval;        /* Safehouse for default values. */
} environment;

EXTERN environment *env;        /* Lists the environment. */

char *b_value(char *name);      /* Get/set the value of a variable. */
int b_setvar(int flags, char *name, char *value);

void parse_code(char *code);    /* Parse boot monitor commands. */

extern int fsok;        /* True if the boot device contains an FS. */
EXTERN u32_t lowsec;    /* Offset to the file system on the boot device. */

/* Called by boot.c: */

void bootminix(void);           /* Load and start a Minix image. */


/* Called by bootimage.c: */

void readerr(off_t sec, int err);
                        /* Report a read error. */
char *ul2a(u32_t n, unsigned b), *ul2a10(u32_t n);
                        /* Transform u32_t to ASCII at base b or base 10. */
long a2l(char *a);
                        /* Cheap atol(). */
unsigned a2x(char *a);
                        /* ASCII to hex. */
dev_t name2dev(char *name);
                        /* Translate a device name to a device number. */
int numprefix(char *s, char **ps);
                        /* True for a numeric prefix. */
int numeric(char *s);
                        /* True for a numeric string. */
char *unix_err(int err);
                        /* Give a descriptive text for some UNIX errors. */
int run_trailer(void);
                        /* Run the trailer function. */

#if DOS
/* The monitor runs under MS-DOS. */
extern char PSP[256];   /* Program Segment Prefix. */
EXTERN char *vdisk;     /* Name of the virtual disk. */
EXTERN char *drun;      /* Initial command from DOS command line. */
#else
/* The monitor uses only the BIOS. */
#define DOS     0
#endif

void readblock(off_t, char *, int);
void delay(char *);

/*
 * $PchId: boot.h,v 1.12 2002/02/27 19:42:45 philip Exp $
 */

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