test4.c

linux 的引导程序源码The Microsoft&reg Windows&reg Software Development Kit (SDK) provides the documentation

	    dword s, e;
	    s = start[k];
	    e = s + length[k];
	    for (j=k+1; j<i; j++) {
	    	dword ss, ee;
	    	ss = start[j];
	    	ee = ss + length[j];
		if (!(ss < s && ee <= s || ss >= e && ee > e)) {
		    printf("*** Memory areas %d and %d overlap ***\n", k, j);
		    ovlap++;
		}
	    }
	}
	if (!ovlap) printf("No memory areas overlap\n");
    } else {
	printf("Returns:\n");
	if (b==-1) print_carry(1);
	else if (b==-2) printf("    EAX=<trash>\n");
	else if (b==-3) printf("    EAX=%lx  EBX=********  ECX=<trash>\n", E820_MAGIC);
	else printf("    EAX=%lx  EBX=00000000\n", E820_MAGIC);
	printf("\nFunction is not supported.\n");
    }


    pause();
    printf(SPACER
    		"Int 15h  Function E801h\t\t[EXT]\n"
    		"Get Extended Memory Blocks\n\n"
    		"Call With:\n    ");
    reg.x.ax = 0xE801;
    print_regs(&reg);
    int86(0x15, &reg, &oreg);
    printf("\nReturns:\n    ");
    print_regs(&oreg);
    print_carry(oreg.x.cflag);

    if (!oreg.x.cflag) {
	printf("\nNumber of 1K blocks between 1M and 16M:  %u\n", oreg.x.ax);
	printf(  "Number of 64K blocks above 16M:  %u\n", oreg.x.bx);
	t = 1024L*(oreg.x.ax+1024);
	t += 64L*1024L*oreg.x.bx;
	if (!hma) hma = t;
	else if (hma!=t) printf("A different amount of memory is reported by this function\n");
    }
    else printf("\nFunction is not supported.\n");

    pause();
    printf(SPACER
    		"Int 15h  Function 88h\t\t[AT][PS/2]\n"
    		"Get Extended Memory Size\n\n"
    		"Call With:\n    ");
    reg.x.ax = 0x8800;
    print_regs(&reg);
    int86(0x15, &reg, &reg);
    printf("\nReturns:\n    ");
    print_regs(&reg);
    printf("\nThere is ");
    decimal( (unsigned long)reg.x.ax );
    printf("K of extended memory.\n");

    t = (reg.x.ax + 1024L) * 1024L;
    if (!hma) hma = t;
}    
    
static
int get_video_mode(void)
{
    int m, row, col;
    
    pause();
    printf(SPACER
    		"Int 10h  Function 0Fh\t\t[MDA][CGA][PCjr]\n"
    		"Get Video Mode\t\t\t[EGA][MCGA][VGA]\n\n"
    		"Call With:\n    ");
    reg.x.ax = 0x0F00;
    reg.x.bx = -1;
    print_regs(&reg);
    int86(0x10, &reg, &reg);
    printf("\nReturns:\n    ");
    print_regs(&reg);
    m = reg.h.al;
    __set_es(0x40);		/* address BIOS data area */
    reg.h.bl = row = __peek_es(0x84);
    printf("Fetch 0040:0084 (rows-1) to BL\n"
    	"--> ");
    print_regs(&reg);
    col = reg.h.ah;
    printf("\nVideo mode = 0x%02x (%dx%d %s)\n", m, col, row+1,
    	m==7 ? "monochrome" : m==3 ? "color" : "unknown");
    printf("Active display page = %d\n", (int)reg.h.bh);
    
    return !(m==7 || col<80);
}

static
int get_cfg_info(void)
{
    pause();
    printf(SPACER
    		"Int 10h  Function 12h\t\t[EGA][VGA]\n"
    		"Subfunction 10h\n"
    		"Get Configuration Information\n\n"
    		"Call With:\n    ");
    reg.x.ax = 0x1200;
    reg.x.bx = 0xFF10;
    print_regs(&reg);
    int86(0x10, &reg, &reg);
    printf("\nReturns:\n    ");
    print_regs(&reg);
    if (reg.h.bh > 1) return 0;
    
    printf("\n%s display\n", reg.h.bh==0 ? "Color" : reg.h.bh==1 ? "Monochrome" : "Unknown");
    printf("EGA memory = %dK\n", reg.h.bl <= 3 ? (reg.h.bl+1)*64 : 0);
    printf("Feature bits = 0x%02x\n", (int)reg.h.ch);
    printf("Configuration switch = 0x%02x\n", (int)reg.h.cl);
    
    return 1;
}

static
int get_comb_code(void)
{
static char *dcode[] = { "none", "Monochrome", "CGA", "reserved",
  "EGA (color)", "EGA (mono)", "PGA", "VGA (monochrome)", "VGA (color)",
  "reserved", "MCGA (digital color)", "MCGA (monochrome)", "MCGA (color)",
  "UNKNOWN" };
    int code;
    
    pause();
    printf(SPACER
    		"Int 10h  Function 1Ah\t\t[PS/2]\n"
    		"Subfunction 00h\n"
    		"Get Display Combination Code\n\n"
    		"Call With:\n    ");
    reg.x.ax = 0x1A00;
    reg.x.bx = reg.x.cx = 0;
    print_regs(&reg);
    int86(0x10, &reg, &reg);
    printf("\nReturns:\n    ");
    print_regs(&reg);
    if (reg.h.al != 0x1A) return 0;
    
    code = reg.h.bl <= 12 ? reg.h.bl : 13;
    printf("\nActive display: %s\n", dcode[code]);
    code = reg.h.bh <= 12 ? reg.h.bh : 13;
    printf("Inactive display: %s\n", dcode[code]);

    return (reg.h.bl>=4);
}

static void print_io_status(int status)
{
static char *errmsg[] = {"no error", "invalid command", 		/* 0-1 */
	"address mark not found", "disk write-protected",	/* 2-3 */
	"sector not found", "reset failed", "floppy disk removed", /* 4-6 */
	"bad parameter table", "DMA overrun",			/* 7-8 */
	"DMA crossed 64k boundary", "bad sector flag",		/* 9-A */
	"bad track flag", "media type not found",		/* B-C */
	"invalid number of sectors on format",			/* D */
	"control data address mark detected",			/* E */
	"DMA arbitration level out of range",			/* F */
	"uncorrectable CRC or ECC data error",			/* 10 */
	"ECC corrected data error"				/* 11 */
			};
    char *err;
			
    if (status <= 0x11) err = errmsg[status];
    else switch(status) {
    	case 0x20: err = "controller failure"; break;
    	case 0x40: err = "seek failed"; break;
    	case 0x80: err = "disk timeout (failed to respond)"; break;
    	case 0xAA: err = "drive not ready"; break;
    	case 0xBB: err = "undefined error"; break;
    	case 0xCC: err = "write fault"; break;
    	case 0xE0: err = "status register error"; break;
    	case 0xFF: err = "sense operation failed"; break;
    	default:   err = "???";
    }
    printf("    BIOS error code = 0x%02x  (%s)\n", status, err);
}

static
void do_edd(int dev)
{
    int m, subset;
    
    pause();
    printf(SPACER
    		"Int 13h  Function 41h\t\t[EDD]\n"
    		"Check EDD Extensions Present (device %02xh)\n\n"
    		"Call With:\n    ", dev);
    reg.x.ax = 0x41ED;
    reg.x.bx = 0x55AA;
    reg.x.dx = dev;
    print_regs(&reg);
    int86(0x13, &reg, &oreg);
    printf("\nReturns:\n    ");
    print_regs(&oreg);
    print_carry(oreg.x.cflag);
    m = 0;
    if (oreg.x.cflag) print_io_status(oreg.h.ah);
    else if (oreg.x.bx == 0xAA55 && (oreg.x.cx&EDD_SUBSET+EDD_LOCK+EDD_PACKET)) {
	m = 1;
	printf("\nEnhanced Disk Drive support: "); yesno(subset=oreg.x.cx&EDD_SUBSET);
	printf("Drive locking and ejecting: "); yesno(oreg.x.cx&EDD_LOCK);
	printf("Device access using packet calls: "); yesno(oreg.x.cx&EDD_PACKET);
	printf("EDD extensions version%s (hex code %02xh)\n",
		oreg.h.ah==0x30 ? " 3.0" : oreg.h.ah==0x21 ? " 1.1" : "" ,oreg.h.ah);
    }
    
    if (m) {
	struct EDDparam {
	    short size;		/* size of this structure */
	    short flags;	/* information flags */
	    long pcyls;		/* number of physical cylinders */
	    long pheads;	/* number of physical heads/cylinder */
	    long psects;	/* number of physical sectors/track */
	    unsigned		/* number of physical sectors on volume */
	    long sectors_lo, sectors_hi;	/* this is 8 bytes long */
	    short sec_size;	/* number of bytes per sector */
	    unsigned
	    long params;	/* EDD config params (valid only if EDD_SUBSET) */
	} eddparam;

	pause();
	printf(SPACER
		"Int 13h  Function 48h\t\t[EDD]\n"
		"EDD Get Drive Parameters (device %02xh)\n\n"
		"Call With:\n    ", dev);
	eddparam.size = sizeof(eddparam);
	reg.x.si = &eddparam;	/* DS:SI points to buffer */
	reg.x.ax =0x48C6;
	segread(&sreg);
	print_sregs(&sreg);
	printf("    ");
	print_regs(&reg);
	int86x(0x13, &reg, &reg, &sreg);
	printf("\nReturns:\n    ");
	print_sregs(&sreg);
	printf("    ");
	print_regs(&reg);
	print_carry(reg.x.cflag);
#define fl eddparam.flags	
	printf("\nDMA boundary errors handled transparently: "); yesno(fl&1);
	printf("Geometry supplied: "); yesno(fl&2);
	printf("Device is removable: "); yesno(fl&4);
	printf("Device supports write with verify: "); yesno(fl&8);
	if (fl&4) {
	    printf("Device has change-line support: "); yesno(fl&16);
	    printf("Device is lockable: "); yesno(fl&32);
	    printf("No media present; geometry is set to maximum: "); yesno(fl&64);
	}
	printf("Disk geometry (");
	if (fl&2) {
	    printf("C:H:S) = %ld:%ld:%ld (", eddparam.pcyls, eddparam.pheads,
	    			eddparam.psects);
	}
	if (eddparam.sectors_hi == 0) 
	    decimal(eddparam.sectors_lo);
	else printf("0x%x%08x", eddparam.sectors_hi, eddparam.sectors_lo);
	printf(" sectors)\n");
    }
#undef fl
}

static
int do_disk(int dev)
{
static char *drvtyp[] = {"No drive present", "Floppy w/o change-line support",
	"Floppy with change-line support"};
static char *dt[] = {	"5.25\", 40 track, 360K",
			"5.25\", 80 track, 1.2M",
			"3.5\", 80 track, 720K",
			"3.5\", 80 track, 1.44M" };
    int m, mm;
    int c,h,s;
    unsigned long sect;
    
    pause();
    printf(SPACER
    		"Int 13h  Function 15h\t\t[AT][PS/2]\n"
    		"Get Disk Type  (device %02xh)\n\n"
    		"Call With:\n    ", dev);
    reg.x.ax = 0x1500;
    reg.x.bx = 0;
    reg.x.dx = dev;
    print_regs(&reg);
    int86(0x13, &reg, &oreg);
    printf("\nReturns:\n    ");
    print_regs(&oreg);
    print_carry(oreg.x.cflag);
    mm = (oreg.x.cflag==0 && oreg.h.ah!=0);
    m = mm || (dev&0x80)==0;
    if (oreg.x.cflag) print_io_status((int)oreg.h.ah);
    else {
	printf("\n%s",
	    oreg.h.ah < 3 ? drvtyp[oreg.h.ah] :
	    oreg.h.ah != 3 ? "unknown drive type" : "");
	if (oreg.h.ah == 3) {
	    printf("Fixed disk with ");
	    sect = (long)oreg.x.cx<<16 | oreg.x.dx;
	    decimal(sect);
	    printf(" sectors = ");
	    sizeit(sect);
	}
	printf("\n");
    }

    if (m) {
	pause();
	printf(SPACER
			"Int 13h  Function 08h\t\t[PC][AT][PS/2]\n"
			"Get Drive Parameters  (device %02xh)\n\n"
			"Call With:\n    ", dev);
	reg.x.ax = 0x0800;
	reg.x.dx = dev;
	segread(&sreg);
	sreg.es = 0;
	print_sregs(&sreg);
	printf("    ");
	print_regs(&reg);
	int86x(0x13, &reg, &oreg, &sreg);
	printf("\nReturns:\n    ");
	print_sregs(&sreg);
	printf("    ");
	print_regs(&oreg);
	print_carry(oreg.x.cflag);
	if (oreg.x.cflag) print_io_status((int)oreg.h.ah);
	else {
	    last_good_disk = dev;
	    if (mm) {
		printf("\n");
		if (!(dev&0x80)) {
		    printf("Disk type %d = %s\n", (int)oreg.h.bl,
					dt[(oreg.h.bl-1)&3] );
		    printf("Parameter table at %04x:%04x\n",
					sreg.es, oreg.x.di);
		}
		s = (oreg.h.cl & 0x3F);		/* sectors 1..63 */
		h = (int)oreg.h.dh + 1;		/* heads 0..254 */
		c = (((oreg.h.cl & 0xC0)<<2) | oreg.h.ch) + 1;
		printf("Disk geometry (C:H:S) = %d:%d:%d (", c, h, s);
		decimal( sect=(long)c*h*s );
		printf(" sectors) = ");
		sizeit(sect);
		printf("\n%s disks on system = %d\n",
			dev&0x80 ? "Fixed" : "Floppy", oreg.h.dl);
		if (dev & 0x80) {
		    if (dev == 0x80) num_hd = oreg.h.dl;
		    do_edd(dev);
		}
	    }
	}
    }
    
    return m;
}

static
int do_rw(int tries)
{
    int code;
    
    while (tries--) {
	int86x(0x13, &reg, &oreg, &sreg);
	if (oreg.x.cflag == 0 && oreg.x.ax == 0x0001) return 0;
	code = oreg.h.ah;
	oreg.x.ax = 0;
	int86(0x13, &oreg, &oreg);
    }
    return code;
}

static
void do_get_pt(int dev)
{
    int m;
    char buf[SECTOR_SIZE];
    
    printf("Get partition table (device = 0x%x): ", dev);
    segread(&sreg);
    sreg.es = sreg.ss;
    reg.x.ax = 0x0201;
    reg.x.bx = buf;
    reg.x.cx = 1;
    reg.x.dx = dev & 0xFF;
    m = do_rw(5);
    if (m) print_io_status(m);
    else printf("  okay");
    printf("\n");
}

static
void do_vesa(void)
{
    int i;
    char vesa[512];
    
    pause();
    printf(SPACER
    		"Int 10h  Function 4Fh\t\t[VESA]\n"
    		"Subfunction 00h\n"
    		"Check VESA Extensions Present\n\n"
    		"Call With:\n    ");
    reg.x.ax = 0x4F00;
    reg.x.bx = 0;
    segread(&sreg);
    sreg.es = sreg.ss;
    reg.x.di = &vesa[0];
    print_sregs(&sreg);
    printf("    ");
    print_regs(&reg);
    int86x(0x10, &reg, &oreg, &sreg);
    printf("\nReturns:\n    ");
    print_sregs(&sreg);
    printf("    ");
    print_regs(&oreg);
    if (oreg.x.ax != 0x004F) {
	printf("\nVESA BIOS extensions not present\n");
	return;
    }
    if (strncmp(vesa, "VESA", 4)) {
	printf("\nVESA signature not found\n");
	return;
    }
    vesa[4] = 0;
    printf("\n\"%s\" BIOS extensions present\n", vesa);

    pause();
    printf(SPACER
    		"Int 10h  Function 4Fh\t\t[VESA]\n"
    		"Subfunction 01h\n"
    		"Get VESA Mode Information 1\n\n"
    		"Call With:\n    ");
    reg.x.ax = 0x4F01;
    reg.x.cx = 0x101;
    segread(&sreg);
    sreg.es = sreg.ss;
    reg.x.di = &vesa[0];
    print_sregs(&sreg);
    printf("    ");
    print_regs(&reg);
    int86x(0x10, &reg, &oreg, &sreg);
    printf("\nReturns:\n    ");
    print_sregs(&sreg);
    printf("    ");
    print_regs(&oreg);
    i = *(int*)vesa;	/* get mode bits */
    printf("\nMode bits:  0x%04x\n", i);
    printf("640x480x256 mode supported: ");
    yesno(!(0x19 & ~i));
    
    pause();
    printf(SPACER
    		"Int 10h  Function 4Fh\t\t[VESA]\n"
    		"Subfunction 01h\n"
    		"Get VESA Mode Information 3\n\n"
    		"Call With:\n    ");
    reg.x.ax = 0x4F01;
    reg.x.cx = 0x103;
    segread(&sreg);
    sreg.es = sreg.ss;
    reg.x.di = &vesa[0];
    print_sregs(&sreg);
    printf("    ");
    print_regs(&reg);
    int86x(0x10, &reg, &oreg, &sreg);
    printf("\nReturns:\n    ");
    print_sregs(&sreg);
    printf("    ");
    print_regs(&oreg);
    i = *(int*)vesa;	/* get mode bits */
    printf("\nMode bits:  0x%04x\n", i);
    printf("800x600x256 mode supported: ");
    yesno(!(0x19 & ~i));
}

void main(void)
{
    int m, i, dev;
    
    if (!is_msdos()) {
/**	atexit(pause);	**/
	video_fix();	/* for Dumb DELL computers */
    }
#if DEBUG>=1
    printf("Beginning of '___cstartup'\n");
    print_regs(&__argr);
    printf("DS=%04x  ES=%04x  CS=%04x  SS=%04x  SP=%04x  BP=%04x\n",
    	__argseg.ds, __argseg.es, __argseg.cs, __argseg.ss,
    	__argr.x.flags, __argr.x.cflag);
        
    segread(&sreg);
    printf("\nBeginning of '_main'\n");
    print_sregs(&sreg);
#endif
    banner(DISK_VERSION);
    v86test();
#if DEBUG>=2
    sizeit((long)40*2*9);  putch('\n');
    sizeit((long)80*2*15);  putch('\n');
    sizeit((long)80*2*18);  putch('\n');
    sizeit((long)80*2*36);  putch('\n');
    sizeit((long)1024*255*63);  putch('\n');
    sizeit((long)24000*512);  putch('\n');
#endif
    get_equip_cfg();
    get_conv_mem();
    hma = 0;
    get_ext_mem();
    if (hma>1024L*1024L) mov_ext_mem();
    m = get_video_mode();
    if (m) m = get_cfg_info();
    if (m) m = get_comb_code();
    if (m) do_vesa();
#if DEBUG>=3
    printf("\n\nm=%x\n", m);
#endif
    dev = 0; m = 1;
    for (i=BD_MAX_FLOPPY; i && m;) {
	m = do_disk(dev);
	++dev;
	if (--i == 0  &&  (dev & 0x80)==0) {
	    dev = 0x80;
	    i = BD_MAX_HARD;
	}
	if ((dev & 0x7F) >= num_hd) m = 0;
    }
    pause();
    printf(SPACER);
    for (dev = 0x80; dev <= last_good_disk; dev++) do_get_pt(dev);
    
    if (!is_msdos()) {
	printf("\n\nInitial SEQ reg 1:  0x%02x\n", video_1);
	pause();
    }
}