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Bochs/bochs/bios/rombios.c
Bryce Denney 7a095b60e4 - now floppy controller returns a proper error response if you try to write 
a read-only disk image.  For systems such as DOS that actually use the
  BIOS services, it was also necessary to add code in int13_diskette_function
  to recognize a write-protected error and return the correct error
  status code (AH=3, Carry Set).
2001-06-13 07:06:10 +00:00

4885 lines
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// Copyright (C) 2001 MandrakeSoft S.A.
//
// MandrakeSoft S.A.
// 43, rue d'Aboukir
// 75002 Paris - France
// http://www.linux-mandrake.com/
// http://www.mandrakesoft.com/
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
/* includes a subset of config.h that can be compiled by bcc, and applies
to this file */
#include "biosconfig.h"
// ROM BIOS for use with Bochs x86 emulation environment
// ROM BIOS compatability entry points:
// ===================================
// $e05b ; POST Entry Point
// $e2c3 ; NMI Handler Entry Point
// $e3fe ; INT 13h Fixed Disk Services Entry Point
// $e401 ; Fixed Disk Parameter Table
// $e6f2 ; INT 19h Boot Load Service Entry Point
// $e6f5 ; Configuration Data Table
// $e729 ; Baud Rate Generator Table
// $e739 ; INT 14h Serial Communications Service Entry Point
// $e82e ; INT 16h Keyboard Service Entry Point
// $e987 ; INT 09h Keyboard Service Entry Point
// $ec59 ; INT 13h Diskette Service Entry Point
// $ef57 ; INT 0Eh Diskette Hardware ISR Entry Point
// $efc7 ; Diskette Controller Parameter Table
// $efd2 ; INT 17h Printer Service Entry Point
// $f045 ; INT 10 Functions 0-Fh Entry Point
// $f065 ; INT 10h Video Support Service Entry Point
// $f0a4 ; MDA/CGA Video Parameter Table (INT 1Dh)
// $f841 ; INT 12h Memory Size Service Entry Point
// $f84d ; INT 11h Equipment List Service Entry Point
// $f859 ; INT 15h System Services Entry Point
// $fa6e ; Character Font for 320x200 & 640x200 Graphics (lower 128 characters)
// $fe6e ; INT 1Ah Time-of-day Service Entry Point
// $fea5 ; INT 08h System Timer ISR Entry Point
// $fef3 ; Initial Interrupt Vector Offsets Loaded by POST
// $ff53 ; IRET Instruction for Dummy Interrupt Handler
// $ff54 ; INT 05h Print Screen Service Entry Point
// $fff0 ; Power-up Entry Point
// $fff5 ; ASCII Date ROM was built - 8 characters in MM/DD/YY
// $fffe ; System Model ID
// old NOTES:
// int74 needs to be reworked. Uses direct [bp] offsets.
// take out int13 printf()s, or conditionally compile them
// int13:
// f04 (verify sectors) isn't complete
// f02/03/04 should set current cyl,etc in BDA
//
// int1a:
// f03/f05 are not complete - just CLC for now
//
// int16_function: default case ?
// NOTES:
// 990104:
// - NMI access (bit7 of addr written to 70h)
// - timer ISR should deal with floppy counter and turn floppy motor off
#define BX_CPU 3
#define BX_USE_PS2_MOUSE 1
#define BX_CALL_INT15_4F 1
#define BX_USE_EBDA 1
#define BX_SUPPORT_FLOPPY 1
/* model byte 0xFC = AT */
#define SYS_MODEL_ID 0xFC
#define SYS_SUBMODEL_ID 0x00
#define BIOS_REVISION 1
#define BIOS_CONFIG_TABLE 0xe6f5
// 1K of base memory used for Extended Bios Data Area (EBDA)
// EBDA is used for PS/2 mouse support, and IDE BIOS, etc.
#define BASE_MEM_IN_K (640 - 1)
#define EBDA_SEG 0x9FC0
#define PANIC_PORT 0x400
// #20 is dec 20
// #$20 is hex 20 = 32
// LDA #$20
// JSR $E820
// LDD .i,S
// JSR $C682
// mov al, #$20
// all hex literals should be prefixed with '0x'
// grep "#[0-9a-fA-F][0-9a-fA-F]" rombios.c
// no mov SEG-REG, #value, must mov register into seg-reg
// grep -i "mov[ ]*.s" rombios.c
#asm
.rom
.org 0x0000
#if BX_CPU >= 3
use16 386
#else
use16 286
#endif
MACRO HALT
;; the HALT macro is called with the line number of the HALT call.
;; The line number is then sent to the PANIC_PORT, causing Bochs to
;; print a BX_PANIC message. This will normally halt the simulation
;; with a message such as "BIOS panic at rombios.c, line 4091".
;; However, users can choose to make panics non-fatal and continue.
mov dx,#PANIC_PORT
mov ax,#?1
out dx,ax
MEND
MACRO JMP_AP
db 0xea
dw ?2
dw ?1
MEND
MACRO SET_INT_VECTOR
mov ax, ?3
mov ?1*4, ax
mov ax, ?2
mov ?1*4+2, ax
MEND
#endasm
typedef unsigned char Bit8u;
typedef unsigned short Bit16u;
typedef unsigned short Boolean;
// for access to RAM area which is used by interrupt vectors
// and BIOS Data Area
typedef struct {
unsigned char filler1[0x400];
unsigned char filler2[0x6c];
Bit16u ticks_low;
Bit16u ticks_high;
Bit8u midnight_flag;
} bios_data_t;
#define BiosData ((bios_data_t *) 0)
typedef struct {
union {
struct {
Bit16u di, si, bp, sp;
Bit16u bx, dx, cx, ax;
} r16;
struct {
Bit16u filler[4];
Bit8u bl, bh, dl, dh, cl, ch, al, ah;
} r8;
} u;
} pusha_regs_t;
typedef struct {
union {
struct {
Bit16u flags;
} r16;
struct {
Bit8u flagsl;
Bit8u flagsh;
} r8;
} u;
} flags_t;
#define SetCF(x) x.u.r8.flagsl |= 0x01
#define SetZF(x) x.u.r8.flagsl |= 0x40
#define ClearCF(x) x.u.r8.flagsl &= 0xfe
#define ClearZF(x) x.u.r8.flagsl &= 0xbf
#define GetCF(x) (x.u.r8.flagsl & 0x01)
typedef struct {
Bit16u ip;
Bit16u cs;
flags_t flags;
} iret_addr_t;
static Bit8u inb();
static Bit8u inb_cmos();
static void outb();
static void outb_cmos();
static Bit16u inw();
static void outw();
static void init_rtc();
static Boolean rtc_updating();
static Bit8u read_byte();
static Bit16u read_word();
static void write_byte();
static void write_word();
static void bios_printf();
static Bit16u UDIV();
static Bit8u inhibit_mouse_int_and_events();
static void enable_mouse_int_and_events();
static Bit8u send_to_mouse_ctrl();
static Bit8u get_mouse_data();
static void set_kbd_command_byte();
static void int09_function();
static void int13_function();
static void int13_diskette_function();
static void int15_function();
static void int16_function();
static void int1a_function();
static void int70_function();
static void int74_function();
//static Bit16u get_DS();
//static void set_DS();
static Bit16u get_SS();
static void enqueue_key();
static unsigned int dequeue_key();
static void set_disk_ret_status();
static void get_hd_geometry();
static void set_diskette_ret_status();
static void set_diskette_current_cyl();
static void determine_floppy_media();
static Boolean floppy_drive_exists();
static Boolean floppy_drive_recal();
static Boolean floppy_media_known();
static Boolean floppy_media_sense();
static void cli();
static Boolean set_enable_a20();
static void debugger_on();
static void debugger_off();
static void keyboard_panic();
static void boot_failure_msg();
static void nmi_handler_msg();
static void print_bios_banner();
static char bios_version_string[] = "BIOS Version is $Id: rombios.c,v 1.14 2001-06-13 07:06:10 bdenney Exp $";
#define DEBUG_ROMBIOS 0
#if DEBUG_ROMBIOS
# define printf(format, p...) bios_printf(0, format, ##p)
# define panic(format, p...) bios_printf(1, format, ##p)
#else
# define printf(format, p...)
# define panic(format, p...) bios_printf(1, format, ##p)
#endif
#define SET_AL(val8) AX = ((AX & 0xff00) | (val8))
#define SET_BL(val8) BX = ((BX & 0xff00) | (val8))
#define SET_CL(val8) CX = ((CX & 0xff00) | (val8))
#define SET_DL(val8) DX = ((DX & 0xff00) | (val8))
#define SET_AH(val8) AX = ((AX & 0x00ff) | ((val8) << 8))
#define SET_BH(val8) BX = ((BX & 0x00ff) | ((val8) << 8))
#define SET_CH(val8) CX = ((CX & 0x00ff) | ((val8) << 8))
#define SET_DH(val8) DX = ((DX & 0x00ff) | ((val8) << 8))
#define GET_AL() ( AX & 0x00ff )
#define GET_BL() ( BX & 0x00ff )
#define GET_CL() ( CX & 0x00ff )
#define GET_DL() ( DX & 0x00ff )
#define GET_AH() ( AX >> 8 )
#define GET_BH() ( BX >> 8 )
#define GET_CH() ( CX >> 8 )
#define GET_DH() ( DX >> 8 )
#define SET_CF() FLAGS |= 0x0001
#define CLEAR_CF() FLAGS &= 0xfffe
#define GET_CF() (FLAGS & 0x0001)
#define SET_ZF() FLAGS |= 0x0040
#define CLEAR_ZF() FLAGS &= 0xffbf
#define GET_ZF() (FLAGS & 0x0040)
#define UNSUPPORTED_FUNCTION 0x86
#define none 0
#define MAX_SCAN_CODE 0x53
static struct {
Bit16u normal;
Bit16u shift;
Bit16u control;
Bit16u alt;
} scan_to_scanascii[MAX_SCAN_CODE + 1] = {
{ none, none, none, none },
{ 0x011b, 0x011b, 0x011b, 0x0100 }, /* escape */
{ 0x0231, 0x0221, none, 0x7800 }, /* 1! */
{ 0x0332, 0x0340, 0x0300, 0x7900 }, /* 2@ */
{ 0x0433, 0x0423, none, 0x7a00 }, /* 3# */
{ 0x0534, 0x0524, none, 0x7b00 }, /* 4$ */
{ 0x0635, 0x0625, none, 0x7c00 }, /* 5% */
{ 0x0736, 0x075e, 0x071e, 0x7d00 }, /* 6^ */
{ 0x0837, 0x0826, none, 0x7e00 }, /* 7& */
{ 0x0938, 0x092a, none, 0x7f00 }, /* 8* */
{ 0x0a39, 0x0a28, none, 0x8000 }, /* 9( */
{ 0x0b30, 0x0b29, none, 0x8100 }, /* 0) */
{ 0x0c2d, 0x0c5f, 0x0c1f, 0x8200 }, /* -_ */
{ 0x0d3d, 0x0d2b, none, 0x8300 }, /* =+ */
{ 0x0e08, 0x0e08, 0x0e7f, none }, /* backspace */
{ 0x0f09, 0x0f00, none, none }, /* tab */
{ 0x1071, 0x1051, 0x1011, 0x1000 }, /* Q */
{ 0x1177, 0x1157, 0x1117, 0x1100 }, /* W */
{ 0x1265, 0x1245, 0x1205, 0x1200 }, /* E */
{ 0x1372, 0x1352, 0x1312, 0x1300 }, /* R */
{ 0x1474, 0x1454, 0x1414, 0x1400 }, /* T */
{ 0x1579, 0x1559, 0x1519, 0x1500 }, /* Y */
{ 0x1675, 0x1655, 0x1615, 0x1600 }, /* U */
{ 0x1769, 0x1749, 0x1709, 0x1700 }, /* I */
{ 0x186f, 0x184f, 0x180f, 0x1800 }, /* O */
{ 0x1970, 0x1950, 0x1910, 0x1900 }, /* P */
{ 0x1a5b, 0x1a7b, 0x1a1b, none }, /* [{ */
{ 0x1b5d, 0x1b7d, 0x1b1d, none }, /* ]} */
{ 0x1c0d, 0x1c0d, 0x1c0a, none }, /* Enter */
{ none, none, none, none }, /* L Ctrl */
{ 0x1e61, 0x1e41, 0x1e01, 0x1e00 }, /* A */
{ 0x1f73, 0x1f53, 0x1f13, 0x1f00 }, /* S */
{ 0x2064, 0x2044, 0x2004, 0x2000 }, /* D */
{ 0x2166, 0x2146, 0x2106, 0x2100 }, /* F */
{ 0x2267, 0x2247, 0x2207, 0x2200 }, /* G */
{ 0x2368, 0x2348, 0x2308, 0x2300 }, /* H */
{ 0x246a, 0x244a, 0x240a, 0x2400 }, /* J */
{ 0x256b, 0x254b, 0x250b, 0x2500 }, /* K */
{ 0x266c, 0x264c, 0x260c, 0x2600 }, /* L */
{ 0x273b, 0x273a, none, none }, /* ;: */
{ 0x2827, 0x2822, none, none }, /* '" */
{ 0x2960, 0x297e, none, none }, /* `~ */
{ none, none, none, none }, /* L shift */
{ 0x2b5c, 0x2b7c, 0x2b1c, none }, /* |\ */
{ 0x2c7a, 0x2c5a, 0x2c1a, 0x2c00 }, /* Z */
{ 0x2d78, 0x2d58, 0x2d18, 0x2d00 }, /* X */
{ 0x2e63, 0x2e43, 0x2e03, 0x2e00 }, /* C */
{ 0x2f76, 0x2f56, 0x2f16, 0x2f00 }, /* V */
{ 0x3062, 0x3042, 0x3002, 0x3000 }, /* B */
{ 0x316e, 0x314e, 0x310e, 0x3100 }, /* N */
{ 0x326d, 0x324d, 0x320d, 0x3200 }, /* M */
{ 0x332c, 0x333c, none, none }, /* ,< */
{ 0x342e, 0x343e, none, none }, /* .> */
{ 0x352f, 0x353f, none, none }, /* /? */
{ none, none, none, none }, /* R Shift */
{ 0x372a, 0x372a, none, none }, /* * */
{ none, none, none, none }, /* L Alt */
{ 0x3920, 0x3920, 0x3920, 0x3920 }, /* space */
{ none, none, none, none }, /* caps lock */
{ 0x3b00, 0x5400, 0x5e00, 0x6800 }, /* F1 */
{ 0x3c00, 0x5500, 0x5f00, 0x6900 }, /* F2 */
{ 0x3d00, 0x5600, 0x6000, 0x6a00 }, /* F3 */
{ 0x3e00, 0x5700, 0x6100, 0x6b00 }, /* F4 */
{ 0x3f00, 0x5800, 0x6200, 0x6c00 }, /* F5 */
{ 0x4000, 0x5900, 0x6300, 0x6d00 }, /* F6 */
{ 0x4100, 0x5a00, 0x6400, 0x6e00 }, /* F7 */
{ 0x4200, 0x5b00, 0x6500, 0x6f00 }, /* F8 */
{ 0x4300, 0x5c00, 0x6600, 0x7000 }, /* F9 */
{ 0x4400, 0x5d00, 0x6700, 0x7100 }, /* F10 */
{ none, none, none, none }, /* Num Lock */
{ none, none, none, none }, /* Scroll Lock */
{ 0x4700, 0x4737, 0x7700, none }, /* 7 Home */
{ 0x4800, 0x4838, none, none }, /* 8 UP */
{ 0x4900, 0x4939, 0x8400, none }, /* 9 PgUp */
{ 0x4a2d, 0x4a2d, none, none }, /* - */
{ 0x4b00, 0x4b34, 0x7300, none }, /* 4 Left */
{ 0x4c00, 0x4c35, none, none }, /* 5 */
{ 0x4d00, 0x4d36, 0x7400, none }, /* 6 Right */
{ 0x4e2b, 0x4e2b, none, none }, /* + */
{ 0x4f00, 0x4f31, 0x7500, none }, /* 1 End */
{ 0x5000, 0x5032, none, none }, /* 2 Down */
{ 0x5100, 0x5133, 0x7600, none }, /* 3 PgDn */
{ 0x5200, 0x5230, none, none }, /* 0 Ins */
{ 0x5300, 0x532e, none, none } /* Del */
};
Bit8u
inb(port)
Bit16u port;
{
#asm
push bp
mov bp, sp
push dx
mov dx, 4[bp]
in al, dx
pop dx
pop bp
#endasm
}
#if 0
Bit16u
inw(port)
Bit16u port;
{
#asm
push bp
mov bp, sp
push dx
mov dx, 4[bp]
in ax, dx
pop dx
pop bp
#endasm
}
#endif
void
outb(port, val)
Bit16u port;
Bit8u val;
{
#asm
push bp
mov bp, sp
push ax
push dx
mov dx, 4[bp]
mov al, 6[bp]
out dx, al
pop dx
pop ax
pop bp
#endasm
}
#if 0
void
outw(port, val)
Bit16u port;
Bit16u val;
{
#asm
push bp
mov bp, sp
push ax
push dx
mov dx, 4[bp]
mov ax, 6[bp]
out dx, ax
pop dx
pop ax
pop bp
#endasm
}
#endif
void
outb_cmos(cmos_reg, val)
Bit8u cmos_reg;
Bit8u val;
{
#asm
push bp
mov bp, sp
mov al, 4[bp] ;; cmos_reg
out 0x70, al
mov al, 6[bp] ;; val
out 0x71, al
pop bp
#endasm
}
Bit8u
inb_cmos(cmos_reg)
Bit8u cmos_reg;
{
#asm
push bp
mov bp, sp
mov al, 4[bp] ;; cmos_reg
out 0x70, al
in al, 0x71
pop bp
#endasm
}
void
init_rtc()
{
outb_cmos(0x0a, 0x26);
outb_cmos(0x0b, 0x02);
inb_cmos(0x0c);
inb_cmos(0x0d);
}
Boolean
rtc_updating()
{
// This function checks to see if the update-in-progress bit
// is set in CMOS Status Register A. If not, it returns 0.
// If it is set, it tries to wait until there is a transition
// to 0, and will return 0 if such a transition occurs. A 1
// is returned only after timing out. The maximum period
// that this bit should be set is constrained to 244useconds.
// The count I use below guarantees coverage or more than
// this time, with any reasonable IPS setting.
Bit16u count;
count = 25000;
while (--count != 0) {
if ( (inb_cmos(0x0a) & 0x80) == 0 )
return(0);
}
return(1); // update-in-progress never transitioned to 0
}
Bit8u
read_byte(seg, offset)
Bit16u seg;
Bit16u offset;
{
#asm
push bp
mov bp, sp
push bx
push ds
mov ax, 4[bp] ; segment
mov ds, ax
mov bx, 6[bp] ; offset
mov al, [bx]
;; al = return value (byte)
pop ds
pop bx
pop bp
#endasm
}
Bit16u
read_word(seg, offset)
Bit16u seg;
Bit16u offset;
{
#asm
push bp
mov bp, sp
push bx
push ds
mov ax, 4[bp] ; segment
mov ds, ax
mov bx, 6[bp] ; offset
mov ax, [bx]
;; ax = return value (word)
pop ds
pop bx
pop bp
#endasm
}
void
write_byte(seg, offset, data)
Bit16u seg;
Bit16u offset;
{
#asm
push bp
mov bp, sp
push ax
push bx
push ds
mov ax, 4[bp] ; segment
mov ds, ax
mov bx, 6[bp] ; offset
mov al, 8[bp] ; data byte
mov [bx], al ; write data byte
pop ds
pop bx
pop ax
pop bp
#endasm
}
void
write_word(seg, offset, data)
Bit16u seg;
Bit16u offset;
{
#asm
push bp
mov bp, sp
push ax
push bx
push ds
mov ax, 4[bp] ; segment
mov ds, ax
mov bx, 6[bp] ; offset
mov ax, 8[bp] ; data word
mov [bx], ax ; write data word
pop ds
pop bx
pop ax
pop bp
#endasm
}
Bit16u
UDIV(a, b)
Bit16u a, b;
{
// divide a by b
// return value in AX is: AL=quotient, AH=remainder
#asm
push bp
mov bp, sp
push bx
mov ax, 4[bp] ;; a
mov bx, 6[bp] ;; b: only low eight bits used
div bl ;; AX / BL --> quotient=AL, remainder=AH
pop bx
pop bp
#endasm
}
Bit16u
UDIV16(a, b)
Bit16u a, b;
{
// divide a by b, discarding remainder
#asm
push bp
mov bp, sp
push dx
push bx
xor dx,dx
mov ax, 4[bp] ;; a
mov bx, 6[bp] ;; b
div bx ;; DX:AX / BX -> AX, DX = remainder
pop bx
pop dx
pop bp
#endasm
}
// Bit16u
//get_DS()
//{
//#asm
// mov ax, ds
//#endasm
//}
// void
//set_DS(ds_selector)
// Bit16u ds_selector;
//{
//#asm
// push bp
// mov bp, sp
//
// push ax
// mov ax, 4[bp] ; ds_selector
// mov ds, ax
// pop ax
//
// pop bp
//#endasm
//}
Bit16u
get_SS()
{
#asm
mov ax, ss
#endasm
}
void
put_int(val, width, neg)
short val, width;
Boolean neg;
{
short nval = UDIV16(val, 10);
if (nval)
put_int(nval, width - 1, neg);
else {
while (--width > 0) outb(0xfff0, ' ');
if (neg) outb(0xfff0, '-');
}
outb(0xfff0, val - (nval * 10) + '0');
}
//--------------------------------------------------------------------------
// bios_printf()
// A compact variable argument printf function which prints its output via
// an I/O port so that it can be logged by Bochs. Currently, only %x is
// supported (or %02x, %04x, etc).
//--------------------------------------------------------------------------
void
bios_printf(bomb, s)
Boolean bomb;
Bit8u *s;
{
Bit8u c, format_char;
Boolean in_format;
short i;
Bit16u *arg_ptr;
Bit16u arg_seg, arg, nibble, shift_count, format_width;
arg_ptr = &s;
arg_seg = get_SS();
in_format = 0;
format_width = 0;
while (c = read_byte(0xf000, s)) {
if ( c == '%' ) {
in_format = 1;
format_width = 0;
}
else if (in_format) {
if ( (c>='0') && (c<='9') ) {
format_width = (format_width * 10) + (c - '0');
}
else if (c == 'x') {
arg_ptr++; // increment to next arg
arg = read_word(arg_seg, arg_ptr);
if (format_width == 0)
format_width = 4;
for (i=format_width-1; i>=0; i--) {
nibble = (arg >> (4 * i)) & 0x000f;
if (nibble <= 9)
outb(0xfff0, nibble + '0');
else
outb(0xfff0, (nibble - 10) + 'A');
}
in_format = 0;
}
else if (c == 'd') {
arg_ptr++; // increment to next arg
arg = read_word(arg_seg, arg_ptr);
if (arg & 0x8000)
put_int(-arg, format_width - 1, 1);
else
put_int(arg, format_width, 0);
in_format = 0;
}
else
panic("bios_printf: unknown format\n");
}
else {
outb(0xfff0, c);
}
s ++;
}
if (bomb) {
#asm
HALT(__LINE__)
#endasm
}
}
void
cli()
{
#asm
cli
#endasm
}
void
keyboard_panic()
{
panic("Keyboard RESET error\n");
}
void
boot_failure_msg(drive)
Bit16u drive;
{
if (drive < 0x80) {
bios_printf(0, "Boot Failure! I could not read floppy drive %d.\n", drive);
} else {
drive &= 0x7f;
bios_printf(0, "Boot Failure! I could not read hard disk %d.\n", drive);
}
}
void
nmi_handler_msg()
{
bios_printf(0, "NMI Handler called\n");
}
void
print_bios_banner()
{
bios_printf(0, bios_version_string);
bios_printf(0, "\n");
}
Boolean
set_enable_a20(val)
Boolean val;
{
Bit8u oldval;
// Use PS2 System Control port A to set A20 enable
// get current setting first
oldval = inb(0x92);
// change A20 status
if (val)
outb(0x92, oldval | 0x02);
else
outb(0x92, oldval & 0xfd);
return((oldval & 0x02) != 0);
}
void
debugger_on()
{
outb(0xfedc, 0x01);
}
void
debugger_off()
{
outb(0xfedc, 0x00);
}
void
int15_function(DI, SI, BP, SP, BX, DX, CX, AX, ES, DS, FLAGS)
Bit16u DI, SI, BP, SP, BX, DX, CX, AX, ES, DS, FLAGS;
{
Bit16u ebda_seg;
Bit8u mouse_flags_1, mouse_flags_2;
Bit16u mouse_driver_seg;
Bit16u mouse_driver_offset;
Bit8u in_byte;
Bit8u response, prev_command_byte;
Boolean prev_a20_enable;
Bit16u base15_00;
Bit8u base23_16;
Bit16u ss;
Bit8u ret, mouse_data1, mouse_data2, mouse_data3;
Bit8u comm_byte;
switch (GET_AH()) {
case 0x24: /* A20 Control */
printf("BIOS: int15: Func 24h, subfunc %02xh, A20 gate control not supported\n", (unsigned) GET_AL());
SET_CF();
SET_AH(UNSUPPORTED_FUNCTION);
break;
case 0x41:
SET_CF();
SET_AH(UNSUPPORTED_FUNCTION);
break;
case 0x4f:
/* keyboard intercept, ignore */
SET_CF();
#if BX_CPU < 2
SET_AH(UNSUPPORTED_FUNCTION);
#endif
break;
case 0x87:
#if BX_CPU < 3
# error "Int15 function 87h not supported on < 80386"
#endif
// +++ should probably have descriptor checks
// +++ should have exception handlers
cli();
prev_a20_enable = set_enable_a20(1); // enable A20 line
// 128K max of transfer on 386+ ???
// source == destination ???
// ES:SI points to descriptor table
// offset use initially comments
// ==============================================
// 00..07 Unused zeros Null descriptor
// 08..0f GDT zeros filled in by BIOS
// 10..17 source ssssssss source of data
// 18..1f dest dddddddd destination of data
// 20..27 CS zeros filled in by BIOS
// 28..2f SS zeros filled in by BIOS
//es:si
//eeee0
//0ssss
//-----
// check for access rights of source & dest here
// Initialize GDT descriptor
base15_00 = (ES << 4) + SI;
base23_16 = ES >> 12;
if (base15_00 < (ES<<4))
base23_16++;
write_word(ES, SI+0x08+0, 47); // limit 15:00 = 6 * 8bytes/descriptor
write_word(ES, SI+0x08+2, base15_00);// base 15:00
write_byte(ES, SI+0x08+4, base23_16);// base 23:16
write_byte(ES, SI+0x08+5, 0x93); // access
write_word(ES, SI+0x08+6, 0x0000); // base 31:24/reserved/limit 19:16
// Initialize CS descriptor
write_word(ES, SI+0x20+0, 0xffff);// limit 15:00 = normal 64K limit
write_word(ES, SI+0x20+2, 0x0000);// base 15:00
write_byte(ES, SI+0x20+4, 0x000f);// base 23:16
write_byte(ES, SI+0x20+5, 0x9b); // access
write_word(ES, SI+0x20+6, 0x0000);// base 31:24/reserved/limit 19:16
// Initialize SS descriptor
ss = get_SS();
base15_00 = ss << 4;
base23_16 = ss >> 12;
write_word(ES, SI+0x28+0, 0xffff); // limit 15:00 = normal 64K limit
write_word(ES, SI+0x28+2, base15_00);// base 15:00
write_byte(ES, SI+0x28+4, base23_16);// base 23:16
write_byte(ES, SI+0x28+5, 0x93); // access
write_word(ES, SI+0x28+6, 0x0000); // base 31:24/reserved/limit 19:16
#asm
// Compile generates locals offset info relative to SP.
// Get CX (word count) from stack.
mov bx, sp
SEG SS
mov cx, _int15_function.CX [bx]
// since we need to set SS:SP, save them to the BDA
// for future restore
mov ax, #0x00
mov ds, ax
mov 0x0469, ss
mov 0x0467, sp
SEG ES
lgdt [si + 0x08]
SEG CS
lidt [pmode_IDT_info]
;; perhaps do something with IDT here
;; set PE bit in CR0
xor eax, eax
mov al, #0x01
mov cr0, eax
;; far jump to flush CPU queue after transition to protected mode
JMP_AP(0x0020, protected_mode)
protected_mode:
;; GDT points to valid descriptor table, now load SS, DS, ES
mov ax, #0x28 ;; 101 000 = 5th descriptor in table, TI=GDT, RPL=00
mov ss, ax
mov ax, #0x10 ;; 010 000 = 2nd descriptor in table, TI=GDT, RPL=00
mov ds, ax
mov ax, #0x18 ;; 011 000 = 3rd descriptor in table, TI=GDT, RPL=00
mov es, ax
xor si, si
xor di, di
cld
rep
movsw ;; move CX words from DS:SI to ES:DI
;; clear CR3 and reset PG bit in CR0 ???
xor eax, eax
mov cr0, eax
;; far jump to flush CPU queue after transition to real mode
JMP_AP(0xf000, real_mode)
real_mode:
;; restore IDT to normal real-mode defaults
SEG CS
lidt [rmode_IDT_info]
// restore SS:SP from the BDA
mov ax, #0x00
mov ds, ax
mov ss, 0x0469
mov sp, 0x0467
#endasm
set_enable_a20(prev_a20_enable);
SET_AH(0);
CLEAR_CF();
break;
case 0x88: /* extended memory size */
#if BX_CPU < 2
SET_AH(UNSUPPORTED_FUNCTION);
SET_CF();
#else
/* ??? change this back later... */
/* number of 1K blocks of extended memory, subtract off 1st 1Meg */
// AX = bx_mem.get_memory_in_k() - 1024;
in_byte = inb_cmos(0x30);
SET_AL(in_byte);
in_byte = inb_cmos(0x31);
SET_AH(in_byte);
CLEAR_CF();
#endif
break;
case 0x90:
/* Device busy interrupt. Called by Int 16h when no key available */
break;
case 0x91:
/* Interrupt complete. Called by Int 16h when key becomes available */
break;
case 0xbf:
printf("BIOS: *** int 15h function AH=bf not yet supported!\n");
SET_CF();
SET_AH(UNSUPPORTED_FUNCTION);
break;
case 0xC0:
#if 0
SET_CF();
SET_AH(UNSUPPORTED_FUNCTION);
break;
#endif
CLEAR_CF();
SET_AH(0);
BX = BIOS_CONFIG_TABLE;
ES = 0xF000;
break;
case 0xc1:
#if BX_USE_PS2_MOUSE
ES = read_word(0x0040, 0x000E);
CLEAR_CF();
#else
SET_CF();
SET_AH(UNSUPPORTED_FUNCTION);
#endif
break;
case 0xC2:
// Return Codes status in AH
// =========================
// 00: success
// 01: invalid subfunction (AL > 7)
// 02: invalid input value (out of allowable range)
// 03: interface error
// 04: resend command received from mouse controller,
// device driver should attempt command again
// 05: cannot enable mouse, since no far call has been installed
// 80/86: mouse service not implemented
#if BX_USE_PS2_MOUSE < 1
SET_CF();
SET_AH(UNSUPPORTED_FUNCTION);
#else
ebda_seg = read_word(0x0040, 0x000E);
switch (GET_AL()) {
case 0: // Disable/Enable Mouse
printf("case 0:\n");
switch (GET_BH()) {
case 0: // Disable Mouse
printf("case 0: disable mouse\n");
inhibit_mouse_int_and_events(); // disable IRQ12 and packets
ret = send_to_mouse_ctrl(0xF5); // disable mouse command
if (ret == 0) {
ret = get_mouse_data(&mouse_data1);
if ( (ret == 0) || (mouse_data1 == 0xFA) ) {
CLEAR_CF();
SET_AH(0);
return;
}
}
// error
SET_CF();
SET_AH(ret);
return;
break;
case 1: // Enable Mouse
printf("case 1: enable mouse\n");
mouse_flags_2 = read_byte(ebda_seg, 0x0027);
if ( (mouse_flags_2 & 0x80) == 0 ) {
//printf("INT 15h C2 Enable Mouse, no far call handler\n");
SET_CF(); // error
SET_AH(5); // no far call installed
return;
}
inhibit_mouse_int_and_events(); // disable IRQ12 and packets
ret = send_to_mouse_ctrl(0xF4); // enable mouse command
if (ret == 0) {
ret = get_mouse_data(&mouse_data1);
if ( (ret == 0) && (mouse_data1 == 0xFA) ) {
enable_mouse_int_and_events(); // turn IRQ12 and packet generation on
CLEAR_CF();
SET_AH(0);
return;
}
}
SET_CF();
SET_AH(ret);
return;
default: // invalid subfunction
//printf("INT 15h C2 AL=0, BH=%02x\n", (unsigned) GET_BH());
SET_CF(); // error
SET_AH(1); // invalid subfunction
return;
}
break;
case 1: // Reset Mouse
case 5: // Initialize Mouse
printf("case 1 or 5:\n");
if (GET_AL() == 5) {
if (GET_BH() != 3)
panic("INT 15h C2 AL=5, BH=%02x\n", (unsigned) GET_BH());
mouse_flags_2 = read_byte(ebda_seg, 0x0027);
mouse_flags_2 = (mouse_flags_2 & 0x00) | GET_BH();
mouse_flags_1 = 0x00;
write_byte(ebda_seg, 0x0026, mouse_flags_1);
write_byte(ebda_seg, 0x0027, mouse_flags_2);
}
inhibit_mouse_int_and_events(); // disable IRQ12 and packets
ret = send_to_mouse_ctrl(0xFF); // disable mouse command
if (ret == 0) {
ret = get_mouse_data(&mouse_data3);
if (mouse_data3 != 0xfa)
panic("Mouse reset returned %02x (should be ack)\n", (unsigned)mouse_data3);
if ( ret == 0 ) {
ret = get_mouse_data(&mouse_data1);
if ( ret == 0 ) {
ret = get_mouse_data(&mouse_data2);
if ( ret == 0 ) {
// turn IRQ12 and packet generation on
enable_mouse_int_and_events();
CLEAR_CF();
SET_AH(0);
SET_BL(mouse_data1);
SET_BH(mouse_data2);
return;
}
}
}
}
// error
SET_CF();
SET_AH(ret);
return;
case 2: // Set Sample Rate
printf("case 2:\n");
switch (GET_BH()) {
case 0: // 10 reports/sec
case 1: // 20 reports/sec
case 2: // 40 reports/sec
case 3: // 60 reports/sec
case 4: // 80 reports/sec
case 5: // 100 reports/sec (default)
case 6: // 200 reports/sec
CLEAR_CF();
SET_AH(0);
break;
default:
panic("INT 15h C2 AL=2, BH=%02x\n", (unsigned) GET_BH());
}
break;
case 3: // Set Resolution
printf("case 3:\n");
// BX:
// 0 = 25 dpi, 1 count per millimeter
// 1 = 50 dpi, 2 counts per millimeter
// 2 = 100 dpi, 4 counts per millimeter
// 3 = 200 dpi, 8 counts per millimeter
CLEAR_CF();
SET_AH(0);
break;
case 4: // Get Device ID
printf("case 4:\n");
CLEAR_CF();
SET_AH(0);
SET_BH(0);
break;
case 6: // Return Status & Set Scaling Factor...
printf("case 6:\n");
switch (GET_BH()) {
case 0: // Return Status
comm_byte = inhibit_mouse_int_and_events(); // disable IRQ12 and packets
ret = send_to_mouse_ctrl(0xE9); // get mouse info command
if (ret == 0) {
ret = get_mouse_data(&mouse_data1);
if (mouse_data1 != 0xfa)
panic("Mouse status returned %02x (should be ack)\n", (unsigned)mouse_data1);
if (ret == 0) {
ret = get_mouse_data(&mouse_data1);
if ( ret == 0 ) {
ret = get_mouse_data(&mouse_data2);
if ( ret == 0 ) {
ret = get_mouse_data(&mouse_data3);
if ( ret == 0 ) {
CLEAR_CF();
SET_AH(0);
SET_BL(mouse_data1);
SET_CL(mouse_data2);
SET_DL(mouse_data3);
set_kbd_command_byte(comm_byte); // restore IRQ12 and serial enable
return;
}
}
}
}
}
// error
SET_CF();
SET_AH(ret);
set_kbd_command_byte(comm_byte); // restore IRQ12 and serial enable
return;
case 1: // Set Scaling Factor to 1:1
CLEAR_CF();
SET_AH(0);
break;
default:
panic("INT 15h C2 AL=6, BH=%02x\n", (unsigned) GET_BH());
}
break;
case 7: // Set Mouse Handler Address
printf("case 7:\n");
mouse_driver_seg = ES;
mouse_driver_offset = BX;
write_word(ebda_seg, 0x0022, mouse_driver_offset);
write_word(ebda_seg, 0x0024, mouse_driver_seg);
mouse_flags_2 = read_byte(ebda_seg, 0x0027);
mouse_flags_2 |= 0x80;
write_byte(ebda_seg, 0x0027, mouse_flags_2);
CLEAR_CF();
SET_AH(0);
break;
default:
printf("case default:\n");
SET_AH(1); // invalid function
SET_CF();
}
#endif
break;
case 0xC4:
printf("BIOS: *** int 15h function AX=%04x, BX=%04x not yet supported!\n",
(unsigned) AX, (unsigned) BX);
SET_CF();
SET_AH(UNSUPPORTED_FUNCTION);
break;
case 0xD8:
printf("BIOS: *** int 15h function AX=D8 not yet supported!\n");
SET_CF();
SET_AH(UNSUPPORTED_FUNCTION);
break;
case 0xe0:
printf("BIOS: *** int 15h function AH=e0 not yet supported!\n");
SET_CF();
SET_AH(UNSUPPORTED_FUNCTION);
break;
default:
printf("BIOS: *** int 15h function AH=%02x not yet supported!\n",
(unsigned) GET_AH());
SET_CF();
SET_AH(UNSUPPORTED_FUNCTION);
break;
}
}
void
int16_function(DI, SI, BP, SP, BX, DX, CX, AX, FLAGS)
Bit16u DI, SI, BP, SP, BX, DX, CX, AX, FLAGS;
{
Bit8u scan_code, ascii_code, shift_flags;
switch (GET_AH()) {
case 0x00: /* read keyboard input */
if ( !dequeue_key(&scan_code, &ascii_code, 1) ) {
panic("KBD: int16h: out of keyboard input\n");
}
AX = (scan_code << 8) | ascii_code;
break;
case 0x01: /* check keyboard status */
if ( !dequeue_key(&scan_code, &ascii_code, 0) ) {
SET_ZF();
return;
}
AX = (scan_code << 8) | ascii_code;
CLEAR_ZF();
break;
case 0x02: /* get shift flag status */
/*AL = 0;*/
shift_flags = read_byte(0x0040, 0x17);
SET_AL(shift_flags);
break;
default:
/*bx_cpu.set_ZF(1);*/
/* ??? */
printf("KBD: unsupported int 16h function %02x\n", GET_AH());
}
}
unsigned int
dequeue_key(scan_code, ascii_code, incr)
Bit8u *scan_code;
Bit8u *ascii_code;
unsigned int incr;
{
Bit16u buffer_start, buffer_end, buffer_head, buffer_tail;
Bit16u ss;
Bit8u acode, scode;
#if BX_CPU < 2
buffer_start = 0x001E;
buffer_end = 0x003E;
#else
buffer_start = read_word(0x0040, 0x0080);
buffer_end = read_word(0x0040, 0x0082);
#endif
buffer_head = read_word(0x0040, 0x001a);
buffer_tail = read_word(0x0040, 0x001c);
if (buffer_head != buffer_tail) {
ss = get_SS();
acode = read_byte(0x0040, buffer_head);
scode = read_byte(0x0040, buffer_head+1);
write_byte(ss, ascii_code, acode);
write_byte(ss, scan_code, scode);
if (incr) {
buffer_head += 2;
if (buffer_head >= buffer_end)
buffer_head = buffer_start;
write_word(0x0040, 0x001a, buffer_head);
}
return(1);
}
else {
return(0);
}
}
Bit8u
inhibit_mouse_int_and_events()
{
Bit8u command_byte, prev_command_byte;
// Turn off IRQ generation and aux data line
if ( inb(0x64) & 0x02 )
panic("inhibmouse: keyboard input buffer full\n");
outb(0x64, 0x20); // get command byte
while ( (inb(0x64) & 0x01) != 0x01 );
prev_command_byte = inb(0x60);
command_byte = prev_command_byte;
//while ( (inb(0x64) & 0x02) );
if ( inb(0x64) & 0x02 )
panic("inhibmouse, keyboard input buffer full\n");
command_byte &= 0xfd; // turn off IRQ 12 generation
command_byte |= 0x20; // disable mouse serial clock line
outb(0x64, 0x60); // write command byte
outb(0x60, command_byte);
return(prev_command_byte);
}
void
enable_mouse_int_and_events()
{
Bit8u command_byte;
// Turn on IRQ generation and aux data line
if ( inb(0x64) & 0x02 )
panic("enabmouse: keyboard input buffer full\n");
outb(0x64, 0x20); // get command byte
while ( (inb(0x64) & 0x01) != 0x01 );
command_byte = inb(0x60);
//while ( (inb(0x64) & 0x02) );
if ( inb(0x64) & 0x02 )
panic("enabmouse, keyboard input buffer full\n");
command_byte |= 0x02; // turn on IRQ 12 generation
command_byte &= 0xdf; // enable mouse serial clock line
outb(0x64, 0x60); // write command byte
outb(0x60, command_byte);
}
Bit8u
send_to_mouse_ctrl(sendbyte)
Bit8u sendbyte;
{
Bit8u response;
// wait for chance to write to ctrl
if ( inb(0x64) & 0x02 )
panic("sendmouse, keyboard input buffer full\n");
outb(0x64, 0xD4);
outb(0x60, sendbyte);
return(0);
}
Bit8u
get_mouse_data(data)
Bit8u *data;
{
Bit8u response;
Bit16u ss;
while ( (inb(0x64) & 0x21) != 0x21 ) {
}
response = inb(0x60);
ss = get_SS();
write_byte(ss, data, response);
return(0);
}
void
set_kbd_command_byte(command_byte)
Bit8u command_byte;
{
if ( inb(0x64) & 0x02 )
panic("setkbdcomm, input buffer full\n");
outb(0x64, 0x60); // write command byte
outb(0x60, command_byte);
}
void
int09_function(DI, SI, BP, SP, BX, DX, CX, AX)
Bit16u DI, SI, BP, SP, BX, DX, CX, AX;
{
Bit8u scancode, asciicode, shift_flags;
//
// DS has been set to F000 before call
//
scancode = GET_AL();
if (scancode == 0) {
printf("KBD: int09 handler: AL=0\n");
return;
}
shift_flags = read_byte(0x0040, 0x17);
switch (scancode) {
case 0x3a: /* Caps Lock press */
shift_flags |= 0x40;
write_byte(0x0040, 0x17, shift_flags);
break;
case 0xba: /* Caps Lock release */
shift_flags &= ~0x40;
write_byte(0x0040, 0x17, shift_flags);
break;
case 0x2a: /* L Shift press */
shift_flags |= 0x02;
write_byte(0x0040, 0x17, shift_flags);
break;
case 0xaa: /* L Shift release */
shift_flags &= ~0x02;
write_byte(0x0040, 0x17, shift_flags);
break;
case 0x36: /* R Shift press */
shift_flags |= 0x01;
write_byte(0x0040, 0x17, shift_flags);
break;
case 0xb6: /* R Shift release */
shift_flags &= ~0x01;
write_byte(0x0040, 0x17, shift_flags);
break;
case 0x1d: /* L Cttrl press */
shift_flags |= 0x04;
write_byte(0x0040, 0x17, shift_flags);
break;
case 0x9d: /* L Cttrl release */
shift_flags &= ~0x04;
write_byte(0x0040, 0x17, shift_flags);
break;
case 0x38: /* L Alt press */
shift_flags |= 0x08;
write_byte(0x0040, 0x17, shift_flags);
break;
case 0xb8: /* L Alt release */
shift_flags &= ~0x08;
write_byte(0x0040, 0x17, shift_flags);
break;
case 0x45: /* Num Lock press */
shift_flags |= 0x20;
write_byte(0x0040, 0x17, shift_flags);
break;
case 0xc5: /* Num Lock release */
shift_flags &= ~0x20;
write_byte(0x0040, 0x17, shift_flags);
break;
default:
if (scancode & 0x80) return; /* toss key releases ... */
if (scancode > MAX_SCAN_CODE) {
panic("KBD: int09h_handler(): unknown scancode read!\n");
return;
}
if (shift_flags & 0x08) { /* ALT */
asciicode = scan_to_scanascii[scancode].alt;
scancode = scan_to_scanascii[scancode].alt >> 8;
}
else if (shift_flags & 0x04) { /* CONTROL */
asciicode = scan_to_scanascii[scancode].control;
scancode = scan_to_scanascii[scancode].control >> 8;
}
else if (shift_flags & 0x43) { /* CAPSLOCK + LSHIFT + RSHIFT */
/* check if both CAPSLOCK and a SHIFT key are pressed */
if ((shift_flags & 0x03) && (shift_flags & 0x40)) {
asciicode = scan_to_scanascii[scancode].normal;
scancode = scan_to_scanascii[scancode].normal >> 8;
}
else {
asciicode = scan_to_scanascii[scancode].shift;
scancode = scan_to_scanascii[scancode].shift >> 8;
}
}
else {
asciicode = scan_to_scanascii[scancode].normal;
scancode = scan_to_scanascii[scancode].normal >> 8;
}
if (scancode==0 && asciicode==0) {
panic("KBD: int09h_handler(): scancode & asciicode are zero?\n");
}
enqueue_key(scancode, asciicode);
break;
}
}
void
enqueue_key(scan_code, ascii_code)
Bit8u scan_code, ascii_code;
{
Bit16u buffer_start, buffer_end, buffer_head, buffer_tail, temp_tail;
//printf("KBD: enqueue_key() called scan:%02x, ascii:%02x\n",
// scan_code, ascii_code);
#if BX_CPU < 2
buffer_start = 0x001E;
buffer_end = 0x003E;
#else
buffer_start = read_word(0x0040, 0x0080);
buffer_end = read_word(0x0040, 0x0082);
#endif
buffer_head = read_word(0x0040, 0x001A);
buffer_tail = read_word(0x0040, 0x001C);
temp_tail = buffer_tail;
buffer_tail += 2;
if (buffer_tail >= buffer_end)
buffer_tail = buffer_start;
if (buffer_tail == buffer_head) {
panic("KBD: dropped key scan=%02x, ascii=%02x\n",
(int) scan_code, (int) ascii_code);
return;
}
write_byte(0x0040, temp_tail, ascii_code);
write_byte(0x0040, temp_tail+1, scan_code);
write_word(0x0040, 0x001C, buffer_tail);
}
void
int74_function(make_farcall, Z, Y, X, status)
Bit16u make_farcall, Z, Y, X, status;
{
Bit8u in_byte, index, package_count;
Bit16u ebda_seg;
Bit8u mouse_flags_1, mouse_flags_2;
printf("entering int74_function\n");
make_farcall = 0;
in_byte = inb(0x64);
if ( (in_byte & 0x21) != 0x21 ) {
return;
}
in_byte = inb(0x60);
printf("int74: read byte %02x\n", in_byte);
ebda_seg = read_word(0x0040, 0x000E);
mouse_flags_1 = read_byte(ebda_seg, 0x0026);
mouse_flags_2 = read_byte(ebda_seg, 0x0027);
if ( (mouse_flags_2 & 0x80) != 0x80 ) {
panic("int74_function:\n");
}
package_count = mouse_flags_2 & 0x07;
index = mouse_flags_1 & 0x07;
write_byte(ebda_seg, 0x28 + index, in_byte);
if ( (index+1) >= package_count ) {
printf("int74_function: make_farcall=1\n");
status = read_byte(ebda_seg, 0x0028 + 0);
X = read_byte(ebda_seg, 0x0028 + 1);
Y = read_byte(ebda_seg, 0x0028 + 2);
Z = 0;
mouse_flags_1 = 0;
// check if far call handler installed
if (mouse_flags_2 & 0x80)
make_farcall = 1;
}
else {
mouse_flags_1++;
}
write_byte(ebda_seg, 0x0026, mouse_flags_1);
}
void
int13_function(DI, SI, BP, SP, BX, DX, CX, AX, ES, FLAGS)
Bit16u DI, SI, BP, SP, BX, DX, CX, AX, ES, FLAGS;
{
Bit8u drive, num_sectors, sector, head, status, mod;
Bit8u n_drives;
Bit16u cyl_mod, ax;
Bit16u max_cylinder, cylinder, total_sectors;
Bit16u hd_cylinders;
Bit8u hd_heads, hd_sectors;
Bit16u val16;
Bit8u sector_count;
unsigned int i;
Bit16u tempbx;
write_byte(0x0040, 0x008e, 0); // clear completion flag
/* at this point, DL is >= 0x80 to be passed from the floppy int13h
handler code */
/* check how many disks first (cmos reg 0x12), return an error if
DL > n_drives */
n_drives = inb_cmos(0x12);
n_drives = ((n_drives & 0xf0)==0) ? 0 :
((n_drives & 0x0f) ? 2 : 1);
if (!((GET_DL()&0x7f) < n_drives)) { /* allow 0, 1, or 2 disks */
SET_AH(0x01);
set_disk_ret_status(0x01);
SET_CF(); /* error occurred */
return;
}
switch (GET_AH()) {
case 0x00: /* disk controller reset */
printf("int13_f00\n");
SET_AH(0);
set_disk_ret_status(0);
set_diskette_ret_status(0);
set_diskette_current_cyl(0, 0); /* current cylinder, diskette 1 */
set_diskette_current_cyl(1, 0); /* current cylinder, diskette 2 */
CLEAR_CF(); /* successful */
return;
break;
case 0x01: /* read disk status */
printf("int13_f01\n");
status = read_byte(0x0040, 0x0074);
SET_AH(status);
set_disk_ret_status(0);
/* set CF if error status read */
if (status) SET_CF();
else CLEAR_CF();
return;
break;
case 0x04: // verify disk sectors
case 0x02: // read disk sectors
drive = GET_DL();
get_hd_geometry(drive, &hd_cylinders, &hd_heads, &hd_sectors);
num_sectors = GET_AL();
cylinder = GET_CH();
cylinder |= ( ((Bit16u) GET_CL()) << 2) & 0x300;
sector = (GET_CL() & 0x3f);
head = GET_DH();
if (hd_cylinders > 1024) {
if (hd_cylinders <= 2048) {
cylinder <<= 1;
}
else if (hd_cylinders <= 4096) {
cylinder <<= 2;
}
else if (hd_cylinders <= 8192) {
cylinder <<= 3;
}
else { // hd_cylinders <= 16384
cylinder <<= 4;
}
ax = UDIV(head, hd_heads);
cyl_mod = ax & 0xff;
head = ax >> 8;
cylinder |= cyl_mod;
}
if ( (cylinder >= hd_cylinders) ||
(sector > hd_sectors) ||
(head >= hd_heads) ) {
SET_AH(1);
set_disk_ret_status(1);
SET_CF(); /* error occurred */
return;
}
if ( (num_sectors > 128) || (num_sectors == 0) )
panic("int13_function(): num_sectors out of range!\n");
if (head > 15)
panic("hard drive BIOS:(read/verify) head > 15\n");
if ( GET_AH() == 0x04 ) {
SET_AH(0);
set_disk_ret_status(0);
CLEAR_CF();
return;
}
status = inb(0x1f7);
if (status & 0x80) {
panic("hard drive BIOS:(read/verify) BUSY bit set\n");
}
outb(0x01f2, num_sectors);
outb(0x01f3, sector);
outb(0x01f4, cylinder & 0x00ff);
outb(0x01f5, cylinder >> 8);
outb(0x01f6, 0xa0 | ((drive&1)<<4) | (head & 0x0f));
outb(0x01f7, 0x20);
while (1) {
status = inb(0x1f7);
if ( !(status & 0x80) ) break;
}
if ( !(status & 0x08) ) {
printf("status was %02x\n", (unsigned) status);
panic("hard drive BIOS:(read/verify) data-request bit not set\n");
}
sector_count = 0;
tempbx = BX;
#asm
sti ;; enable higher priority interrupts
#endasm
while (1) {
#asm
;; store temp bx in real DI register
push bp
mov bp, sp
mov di, _int13_function.tempbx + 2 [bp]
pop bp
;; adjust if there will be an overrun
cmp di, #0xfe00
jbe i13_f02_no_adjust
i13_f02_adjust:
sub di, #0x0200 ; sub 512 bytes from offset
mov ax, es
add ax, #0x0020 ; add 512 to segment
mov es, ax
i13_f02_no_adjust:
mov cx, #0x0100 ;; counter (256 words = 512b)
mov dx, #0x01f0 ;; AT data read port
rep
insw ;; CX words transfered from port(DX) to ES:[DI]
i13_f02_done:
;; store real DI register back to temp bx
push bp
mov bp, sp
mov _int13_function.tempbx + 2 [bp], di
pop bp
#endasm
sector_count++;
num_sectors--;
if (num_sectors == 0) {
status = inb(0x1f7);
if ( (status & 0xc9) != 0x40 )
panic("no sectors left to read/verify, status is %02x\n", (unsigned) status);
break;
}
else {
status = inb(0x1f7);
if ( (status & 0xc9) != 0x48 )
panic("more sectors left to read/verify, status is %02x\n", (unsigned) status);
continue;
}
}
SET_AH(0);
set_disk_ret_status(0);
SET_AL(sector_count);
CLEAR_CF(); /* successful */
return;
break;
case 0x03: /* write disk sectors */
printf("int13_f03\n");
drive = GET_DL ();
get_hd_geometry(drive, &hd_cylinders, &hd_heads, &hd_sectors);
num_sectors = GET_AL();
cylinder = GET_CH();
cylinder |= ( ((Bit16u) GET_CL()) << 2) & 0x300;
sector = (GET_CL() & 0x3f);
head = GET_DH();
if (hd_cylinders > 1024) {
if (hd_cylinders <= 2048) {
cylinder <<= 1;
}
else if (hd_cylinders <= 4096) {
cylinder <<= 2;
}
else if (hd_cylinders <= 8192) {
cylinder <<= 3;
}
else { // hd_cylinders <= 16384
cylinder <<= 4;
}
ax = UDIV(head, hd_heads);
cyl_mod = ax & 0xff;
head = ax >> 8;
cylinder |= cyl_mod;
}
if ( (cylinder >= hd_cylinders) ||
(sector > hd_sectors) ||
(head >= hd_heads) ) {
SET_AH( 1);
set_disk_ret_status(1);
SET_CF(); /* error occurred */
return;
}
if ( (num_sectors > 128) || (num_sectors == 0) )
panic("int13_function(): num_sectors out of range!\n");
if (head > 15)
panic("hard drive BIOS:(read) head > 15\n");
status = inb(0x1f7);
if (status & 0x80) {
panic("hard drive BIOS:(read) BUSY bit set\n");
}
// should check for Drive Ready Bit also in status reg
outb(0x01f2, num_sectors);
outb(0x01f3, sector);
outb(0x01f4, cylinder & 0x00ff);
outb(0x01f5, cylinder >> 8);
outb(0x01f6, 0xa0 | ((drive&1)<<4) | (head & 0x0f));
outb(0x01f7, 0x30);
// wait for busy bit to turn off after seeking
while (1) {
status = inb(0x1f7);
if ( !(status & 0x80) ) break;
}
if ( !(status & 0x08) ) {
printf("status was %02x\n", (unsigned) status);
panic("hard drive BIOS:(write) data-request bit not set\n");
}
sector_count = 0;
tempbx = BX;
#asm
sti ;; enable higher priority interrupts
#endasm
while (1) {
#asm
;; store temp bx in real SI register
push bp
mov bp, sp
mov si, _int13_function.tempbx + 2 [bp]
pop bp
;; adjust if there will be an overrun
cmp si, #0xfe00
jbe i13_f03_no_adjust
i13_f03_adjust:
sub si, #0x0200 ; sub 512 bytes from offset
mov ax, es
add ax, #0x0020 ; add 512 to segment
mov es, ax
i13_f03_no_adjust:
mov cx, #0x0100 ;; counter (256 words = 512b)
mov dx, #0x01f0 ;; AT data read port
seg ES
rep
outsw ;; CX words tranfered from ES:[SI] to port(DX)
;; store real SI register back to temp bx
push bp
mov bp, sp
mov _int13_function.tempbx + 2 [bp], si
pop bp
#endasm
sector_count++;
num_sectors--;
if (num_sectors == 0) {
status = inb(0x1f7);
if ( (status & 0xe9) != 0x40 )
panic("no sectors left to write, status is %02x\n", (unsigned) status);
break;
}
else {
status = inb(0x1f7);
if ( (status & 0xc9) != 0x48 )
panic("more sectors left to write, status is %02x\n", (unsigned) status);
continue;
}
}
SET_AH(0);
set_disk_ret_status(0);
SET_AL(sector_count);
CLEAR_CF(); /* successful */
return;
break;
case 0x05: /* format disk track */
printf("int13_f05\n");
panic("format disk track called\n");
/* nop */
SET_AH(0);
set_disk_ret_status(0);
CLEAR_CF(); /* successful */
return;
break;
case 0x08: /* read disk drive parameters */
printf("int13_f08\n");
drive = GET_DL ();
get_hd_geometry(drive, &hd_cylinders, &hd_heads, &hd_sectors);
// translate CHS
//
if (hd_cylinders <= 1024) {
// hd_cylinders >>= 0;
// hd_heads <<= 0;
}
else if (hd_cylinders <= 2048) {
hd_cylinders >>= 1;
hd_heads <<= 1;
}
else if (hd_cylinders <= 4096) {
hd_cylinders >>= 2;
hd_heads <<= 2;
}
else if (hd_cylinders <= 8192) {
hd_cylinders >>= 3;
hd_heads <<= 3;
}
else { // hd_cylinders <= 16384
hd_cylinders >>= 4;
hd_heads <<= 4;
}
max_cylinder = hd_cylinders - 2; /* 0 based */
SET_AL(0);
SET_CH(max_cylinder & 0xff);
SET_CL(((max_cylinder >> 2) & 0xc0) | (hd_sectors & 0x3f));
SET_DH(hd_heads - 1);
SET_DL(n_drives); /* returns 0, 1, or 2 hard drives */
SET_AH(0);
set_disk_ret_status(0);
CLEAR_CF(); /* successful */
return;
break;
case 0x09: /* initialize drive parameters */
printf("int13_f09\n");
SET_AH(0);
set_disk_ret_status(0);
CLEAR_CF(); /* successful */
return;
break;
case 0x0a: /* read disk sectors with ECC */
printf("int13_f0a\n");
case 0x0b: /* write disk sectors with ECC */
printf("int13_f0b\n");
panic("int13h Functions 0Ah & 0Bh not implemented!\n");
return;
break;
case 0x0c: /* seek to specified cylinder */
printf("int13_f0c\n");
printf("int13h function 0ch (seek) not implemented!\n");
SET_AH(0);
set_disk_ret_status(0);
CLEAR_CF(); /* successful */
return;
break;
case 0x0d: /* alternate disk reset */
printf("int13_f0d\n");
SET_AH(0);
set_disk_ret_status(0);
CLEAR_CF(); /* successful */
return;
break;
case 0x10: /* check drive ready */
printf("int13_f10\n");
//SET_AH(0);
//set_disk_ret_status(0);
//CLEAR_CF(); /* successful */
//return;
//break;
// should look at 40:8E also???
status = inb(0x01f7);
if ( (status & 0xc0) == 0x40 ) {
SET_AH(0);
set_disk_ret_status(0);
CLEAR_CF(); // drive ready
return;
}
else {
SET_AH(0xAA);
set_disk_ret_status(0xAA);
SET_CF(); // not ready
return;
}
break;
case 0x11: /* recalibrate */
printf("int13_f11\n");
SET_AH(0);
set_disk_ret_status(0);
CLEAR_CF(); /* successful */
return;
break;
case 0x14: /* controller internal diagnostic */
printf("int13_f14\n");
SET_AH(0);
set_disk_ret_status(0);
CLEAR_CF(); /* successful */
SET_AL(0);
return;
break;
case 0x15: /* read disk drive size */
drive = GET_DL();
get_hd_geometry(drive, &hd_cylinders, &hd_heads, &hd_sectors);
#asm
push bp
mov bp, sp
mov al, _int13_function.hd_heads + 2 [bp]
mov ah, _int13_function.hd_sectors + 2 [bp]
mul al, ah ;; ax = heads * sectors
mov bx, _int13_function.hd_cylinders + 2 [bp]
dec bx ;; use (cylinders - 1) ???
mul ax, bx ;; dx:ax = (cylinders -1) * (heads * sectors)
;; now we need to move the 32bit result dx:ax to what the
;; BIOS wants which is cx:dx.
;; and then into CX:DX on the stack
mov _int13_function.CX + 2 [bp], dx
mov _int13_function.DX + 2 [bp], ax
pop bp
#endasm
SET_AH(3); // hard disk accessible
set_disk_ret_status(0); // ??? should this be 0
CLEAR_CF(); // successful
return;
break;
case 0x18: /* */
case 0x41: // IBM/MS installation check
printf("int13_f18,41\n");
SET_AH(1); // unsupported
set_disk_ret_status(1);
SET_CF(); /* unsuccessful */
return;
break;
default:
panic("case 0x%x found in int13_function()\n", (unsigned) GET_AH());
break;
}
}
//////////////////////
// FLOPPY functions //
//////////////////////
Boolean
floppy_media_known(drive)
Bit16u drive;
{
Bit8u val8;
Bit16u media_state_offset;
val8 = read_byte(0x0040, 0x003e); // diskette recal status
if (drive)
val8 >>= 1;
val8 &= 0x01;
if (val8 == 0)
return(0);
media_state_offset = 0x0090;
if (drive)
media_state_offset += 1;
val8 = read_byte(0x0040, media_state_offset);
val8 = (val8 >> 4) & 0x01;
if (val8 == 0)
return(0);
// check pass, return KNOWN
return(1);
}
Boolean
floppy_media_sense(drive)
Bit16u drive;
{
Boolean retval;
Bit16u media_state_offset;
Bit8u drive_type, config_data, media_state;
if (floppy_drive_recal(drive) == 0) {
return(0);
}
// for now cheat and get drive type from CMOS,
// assume media is same as drive type
drive_type = inb_cmos(0x10);
if (drive == 0)
drive_type >>= 4;
else
drive_type &= 0x0f;
if ( drive_type == 2 ) {
// 1.2 MB 5.25" drive
config_data = 0x00; // 0000 0000
media_state = 0x25; // 0001 0101
retval = 1;
}
else if ( drive_type == 3 ) {
// 720K 3.5" drive
config_data = 0x00; // 0000 0000 ???
media_state = 0x17; // 0001 0111
retval = 1;
}
else if ( drive_type == 4 ) {
// 1.44 MB 3.5" drive
config_data = 0x00; // 0000 0000
media_state = 0x17; // 0001 0111
retval = 1;
}
else if ( drive_type == 5 ) {
// 2.88 MB 3.5" drive
config_data = 0xCC; // 1100 1100
media_state = 0xD7; // 1101 0111
retval = 1;
}
else {
// not recognized
config_data = 0x00; // 0000 0000
media_state = 0x00; // 0000 0000
retval = 0;
}
if (drive == 0)
media_state_offset = 0x90;
else
media_state_offset = 0x91;
write_byte(0x0040, 0x008B, config_data);
write_byte(0x0040, media_state_offset, media_state);
return(retval);
}
Boolean
floppy_drive_recal(drive)
Bit16u drive;
{
Bit8u val8, dor;
Bit16u curr_cyl_offset;
// set 40:3e bit 7 to 0
val8 = read_byte(0x0000, 0x043e);
val8 &= 0x7f;
write_byte(0x0000, 0x043e, val8);
// turn on motor of selected drive, DMA & int enabled, normal operation
if (drive)
dor = 0x20;
else
dor = 0x10;
dor |= 0x0c;
dor |= drive;
outb(0x03f2, dor);
// check port 3f4 for drive readiness
val8 = inb(0x3f4);
if ( (val8 & 0xf0) != 0x80 )
panic("floppy recal:f07: ctrl not ready\n");
// send Recalibrate command (2 bytes) to controller
outb(0x03f5, 0x07); // 07: Recalibrate
outb(0x03f5, drive); // 0=drive0, 1=drive1
// turn on interrupts
#asm
sti
#endasm
// wait on 40:3e bit 7 to become 1
val8 = (read_byte(0x0000, 0x043e) & 0x80);
while ( val8 == 0 ) {
val8 = (read_byte(0x0000, 0x043e) & 0x80);
}
val8 = 0; // separate asm from while() loop
// turn off interrupts
#asm
cli
#endasm
// set 40:3e bit 7 to 0, and calibrated bit
val8 = read_byte(0x0000, 0x043e);
val8 &= 0x7f;
if (drive) {
val8 |= 0x02; // Drive 1 calibrated
curr_cyl_offset = 0x0095;
}
else {
val8 |= 0x01; // Drive 0 calibrated
curr_cyl_offset = 0x0094;
}
write_byte(0x0040, 0x003e, val8);
write_byte(0x0040, curr_cyl_offset, 0); // current cylinder is 0
return(1);
}
Boolean
floppy_drive_exists(drive)
Bit16u drive;
{
Bit8u drive_type;
// check CMOS to see if drive exists
drive_type = inb_cmos(0x10);
if (drive == 0)
drive_type >>= 4;
else
drive_type &= 0x0f;
if ( drive_type == 0 )
return(0);
else
return(1);
}
#if BX_SUPPORT_FLOPPY
void
int13_diskette_function(DI, SI, BP, SP, BX, DX, CX, AX, ES, FLAGS)
Bit16u DI, SI, BP, SP, BX, DX, CX, AX, ES, FLAGS;
{
Bit8u drive, num_sectors, track, sector, head, status;
Bit16u base_address, base_count, base_es;
Bit8u page, mode_register, val8, dor;
Bit8u return_status[7];
Bit8u drive_type, num_floppies, ah;
Bit16u es, last_addr;
//printf("BIOS: int13: AX=%04x BX=%04x CX=%04x DX=%04x\n", AX, BX, CX, DX);
ah = GET_AH();
switch ( ah ) {
case 0x00: // diskette controller reset
printf("floppy f00\n");
drive = GET_DL();
if (drive > 1) {
SET_AH(1); // invalid param
set_diskette_ret_status(1);
SET_CF();
return;
}
drive_type = inb_cmos(0x10);
if (drive == 0)
drive_type >>= 4;
else
drive_type &= 0x0f;
if (drive_type == 0) {
SET_AH(0x80); // drive not responding
set_diskette_ret_status(0x80);
SET_CF();
return;
}
SET_AH(0);
set_diskette_ret_status(0);
CLEAR_CF(); // successful
set_diskette_current_cyl(drive, 0); // current cylinder
return;
case 0x01: // Read Diskette Status
CLEAR_CF();
val8 = read_byte(0x0000, 0x0441);
SET_AH(val8);
if (val8) {
SET_CF();
}
return;
case 0x02: // Read Diskette Sectors
case 0x03: // Write Diskette Sectors
case 0x04: // Verify Diskette Sectors
num_sectors = GET_AL();
track = GET_CH();
sector = GET_CL();
head = GET_DH();
drive = GET_DL();
if ( (drive > 1) || (head > 1) ||
(num_sectors == 0) || (num_sectors > 72) ) {
printf("floppy: drive>1 || head>1 ...\n");
SET_AH(1);
set_diskette_ret_status(1);
SET_AL(0); // no sectors read
SET_CF(); // error occurred
return;
}
// see if drive exists
if (floppy_drive_exists(drive) == 0) {
SET_AH(0x80); // not responding
set_diskette_ret_status(0x80);
SET_AL(0); // no sectors read
SET_CF(); // error occurred
return;
}
// see if media in drive, and type is known
if (floppy_media_known(drive) == 0) {
if (floppy_media_sense(drive) == 0) {
SET_AH(0x0C); // Media type not found
set_diskette_ret_status(0x0C);
SET_AL(0); // no sectors read
SET_CF(); // error occurred
return;
}
}
if (ah == 0x02) {
// Read Diskette Sectors
//-----------------------------------
// set up DMA controller for transfer
//-----------------------------------
// es:bx = pointer to where to place information from diskette
// port 04: DMA-1 base and current address, channel 2
// port 05: DMA-1 base and current count, channel 2
page = (ES >> 12); // upper 4 bits
base_es = (ES << 4); // lower 16bits contributed by ES
base_address = base_es + BX; // lower 16 bits of address
// contributed by ES:BX
if ( base_address < base_es ) {
// in case of carry, adjust page by 1
page++;
}
base_count = (num_sectors * 512) - 1;
// check for 64K boundary overrun
last_addr = base_address + base_count;
if (last_addr < base_address) {
SET_AH(0x09);
set_diskette_ret_status(0x09);
SET_AL(0); // no sectors read
SET_CF(); // error occurred
return;
}
printf("masking DMA-1 c2\n");
outb(0x000a, 0x06);
printf("clear flip-flop\n");
outb(0x000c, 0x00); // clear flip-flop
outb(0x0004, base_address);
outb(0x0004, base_address>>8);
printf("clear flip-flop\n");
outb(0x000c, 0x00); // clear flip-flop
outb(0x0005, base_count);
outb(0x0005, base_count>>8);
// port 0b: DMA-1 Mode Register
mode_register = 0x46; // single mode, increment, autoinit disable,
// transfer type=write, channel 2
printf("setting mode register\n");
outb(0x000b, mode_register);
printf("setting page register\n");
// port 81: DMA-1 Page Register, channel 2
outb(0x0081, page);
printf("unmask chan 2\n");
outb(0x000a, 0x02); // unmask channel 2
printf("unmasking DMA-1 c2\n");
outb(0x000a, 0x02);
//--------------------------------------
// set up floppy controller for transfer
//--------------------------------------
// set 40:3e bit 7 to 0
val8 = read_byte(0x0000, 0x043e);
val8 &= 0x7f;
write_byte(0x0000, 0x043e, val8);
// turn on motor of selected drive, DMA & int enabled, normal operation
if (drive)
dor = 0x20;
else
dor = 0x10;
dor |= 0x0c;
dor |= drive;
outb(0x03f2, dor);
// check port 3f4 for drive readiness
val8 = inb(0x3f4);
if ( (val8 & 0xf0) != 0x80 )
panic("int13_diskette:f02: ctrl not ready\n");
// send read-normal-data command (9 bytes) to controller
outb(0x03f5, 0xe6); // e6: read normal data
outb(0x03f5, (head << 2) | drive); // HD DR1 DR2
outb(0x03f5, track);
outb(0x03f5, head);
outb(0x03f5, sector);
outb(0x03f5, 2); // 512 byte sector size
outb(0x03f5, 0); // last sector number possible on track
outb(0x03f5, 0); // Gap length
outb(0x03f5, 0xff); // Gap length
// turn on interrupts
#asm
sti
#endasm
// wait on 40:3e bit 7 to become 1
val8 = (read_byte(0x0000, 0x043e) & 0x80);
while ( val8 == 0 ) {
val8 = (read_byte(0x0000, 0x043e) & 0x80);
}
val8 = 0; // separate asm from while() loop
// turn off interrupts
#asm
cli
#endasm
// set 40:3e bit 7 to 0
val8 = read_byte(0x0000, 0x043e);
val8 &= 0x7f;
write_byte(0x0000, 0x043e, val8);
// check port 3f4 for accessibility to status bytes
val8 = inb(0x3f4);
if ( (val8 & 0xc0) != 0xc0 )
panic("int13_diskette: ctrl not ready\n");
// read 7 return status bytes from controller
// using loop index broken, have to unroll...
return_status[0] = inb(0x3f5);
return_status[1] = inb(0x3f5);
return_status[2] = inb(0x3f5);
return_status[3] = inb(0x3f5);
return_status[4] = inb(0x3f5);
return_status[5] = inb(0x3f5);
return_status[6] = inb(0x3f5);
// record in BIOS Data Area
write_byte(0x0040, 0x0042, return_status[0]);
write_byte(0x0040, 0x0043, return_status[1]);
write_byte(0x0040, 0x0044, return_status[2]);
write_byte(0x0040, 0x0045, return_status[3]);
write_byte(0x0040, 0x0046, return_status[4]);
write_byte(0x0040, 0x0047, return_status[5]);
write_byte(0x0040, 0x0048, return_status[6]);
if ( (return_status[0] & 0xc0) != 0 ) {
SET_AH(0x20);
set_diskette_ret_status(0x20);
SET_AL(0); // no sectors read
SET_CF(); // error occurred
return;
}
// ??? should track be new val from return_status[3] ?
set_diskette_current_cyl(drive, track);
// AL = number of sectors read (same value as passed)
SET_AH(0x00); // success
CLEAR_CF(); // success
return;
}
else if (ah == 0x03) {
// Write Diskette Sectors
//-----------------------------------
// set up DMA controller for transfer
//-----------------------------------
// es:bx = pointer to where to place information from diskette
// port 04: DMA-1 base and current address, channel 2
// port 05: DMA-1 base and current count, channel 2
page = (ES >> 12); // upper 4 bits
base_es = (ES << 4); // lower 16bits contributed by ES
base_address = base_es + BX; // lower 16 bits of address
// contributed by ES:BX
if ( base_address < base_es ) {
// in case of carry, adjust page by 1
page++;
}
base_count = (num_sectors * 512) - 1;
// check for 64K boundary overrun
last_addr = base_address + base_count;
if (last_addr < base_address) {
SET_AH(0x09);
set_diskette_ret_status(0x09);
SET_AL(0); // no sectors read
SET_CF(); // error occurred
return;
}
printf("masking DMA-1 c2\n");
outb(0x000a, 0x06);
outb(0x000c, 0x00); // clear flip-flop
outb(0x0004, base_address);
outb(0x0004, base_address>>8);
outb(0x000c, 0x00); // clear flip-flop
outb(0x0005, base_count);
outb(0x0005, base_count>>8);
// port 0b: DMA-1 Mode Register
mode_register = 0x4a; // single mode, increment, autoinit disable,
// transfer type=read, channel 2
outb(0x000b, mode_register);
// port 81: DMA-1 Page Register, channel 2
outb(0x0081, page);
printf("unmasking DMA-1 c2\n");
outb(0x000a, 0x02);
//--------------------------------------
// set up floppy controller for transfer
//--------------------------------------
// set 40:3e bit 7 to 0
val8 = read_byte(0x0000, 0x043e);
val8 &= 0x7f;
write_byte(0x0000, 0x043e, val8);
// turn on motor of selected drive, DMA & int enabled, normal operation
if (drive)
dor = 0x20;
else
dor = 0x10;
dor |= 0x0c;
dor |= drive;
outb(0x03f2, dor);
// check port 3f4 for drive readiness
val8 = inb(0x3f4);
if ( (val8 & 0xf0) != 0x80 )
panic("int13_diskette:f03: ctrl not ready\n");
// send read-normal-data command (9 bytes) to controller
outb(0x03f5, 0xc5); // c5: write normal data
outb(0x03f5, (head << 2) | drive); // HD DR1 DR2
outb(0x03f5, track);
outb(0x03f5, head);
outb(0x03f5, sector);
outb(0x03f5, 2); // 512 byte sector size
outb(0x03f5, 0); // last sector number possible on track
outb(0x03f5, 0); // Gap length
outb(0x03f5, 0xff); // Gap length
// turn on interrupts
#asm
sti
#endasm
// wait on 40:3e bit 7 to become 1
val8 = (read_byte(0x0000, 0x043e) & 0x80);
while ( val8 == 0 ) {
val8 = (read_byte(0x0000, 0x043e) & 0x80);
}
val8 = 0; // separate asm from while() loop
// turn off interrupts
#asm
cli
#endasm
// set 40:3e bit 7 to 0
val8 = read_byte(0x0000, 0x043e);
val8 &= 0x7f;
write_byte(0x0000, 0x043e, val8);
// check port 3f4 for accessibility to status bytes
val8 = inb(0x3f4);
if ( (val8 & 0xc0) != 0xc0 )
panic("int13_diskette: ctrl not ready\n");
// read 7 return status bytes from controller
// using loop index broken, have to unroll...
return_status[0] = inb(0x3f5);
return_status[1] = inb(0x3f5);
return_status[2] = inb(0x3f5);
return_status[3] = inb(0x3f5);
return_status[4] = inb(0x3f5);
return_status[5] = inb(0x3f5);
return_status[6] = inb(0x3f5);
// record in BIOS Data Area
write_byte(0x0040, 0x0042, return_status[0]);
write_byte(0x0040, 0x0043, return_status[1]);
write_byte(0x0040, 0x0044, return_status[2]);
write_byte(0x0040, 0x0045, return_status[3]);
write_byte(0x0040, 0x0046, return_status[4]);
write_byte(0x0040, 0x0047, return_status[5]);
write_byte(0x0040, 0x0048, return_status[6]);
if ( (return_status[0] & 0xc0) != 0 ) {
if ( (return_status[1] & 0x02) != 0 ) {
// diskette not writable.
// AH=status code=0x03 (tried to write on write-protected disk)
// AL=number of sectors written=0
AX = 0x0300;
SET_CF();
return;
} else {
panic("int13_diskette_function: read error\n");
}
}
// ??? should track be new val from return_status[3] ?
set_diskette_current_cyl(drive, track);
// AL = number of sectors read (same value as passed)
SET_AH(0x00); // success
CLEAR_CF(); // success
return;
}
else { // if (ah == 0x04)
// Verify Diskette Sectors
// ??? should track be new val from return_status[3] ?
set_diskette_current_cyl(drive, track);
// AL = number of sectors verified (same value as passed)
CLEAR_CF(); // success
SET_AH(0x00); // success
return;
}
case 0x05: // format diskette track
printf("floppy f05\n");
num_sectors = GET_AL();
track = GET_CH();
head = GET_DH();
drive = GET_DL();
if (drive > 1) {
SET_AH(1);
set_diskette_ret_status(1);
SET_CF(); // error occurred
}
drive_type = inb_cmos(0x10);
if (drive == 0)
drive_type >>= 4;
else
drive_type &= 0x0f;
if (drive_type == 0) {
SET_AH(0x80); // drive not responding
set_diskette_ret_status(0x80);
SET_CF(); // error occurred
return;
}
/* nop */
SET_AH(0);
set_diskette_ret_status(0);
set_diskette_current_cyl(drive, track);
CLEAR_CF(); // successful
return;
case 0x08: // read diskette drive parameters
printf("floppy f08\n");
drive = GET_DL();
if (drive>1) {
AX = 0;
BX = 0;
CX = 0;
DX = 0;
//ES = 0; // ???
SET_DL(num_floppies);
//set_diskette_ret_status(AH=1);
SET_CF();
return;
}
drive_type = inb_cmos(0x10);
num_floppies = 0;
if (drive_type & 0xf0)
num_floppies++;
if (drive_type & 0x0f)
num_floppies++;
if (drive == 0)
drive_type >>= 4;
else
drive_type &= 0x0f;
SET_BH(0);
SET_BL(drive_type);
SET_AH(0);
SET_AL(0);
SET_DL(num_floppies);
switch (drive_type) {
case 0: // none
CX = 0;
SET_DH(0); // max head #
break;
case 1: // 360KB, 5.25"
CX = 0x2709; // 40 tracks, 9 sectors
SET_DH(1); // max head #
break;
case 2: // 1.2MB, 5.25"
CX = 0x4f0f; // 80 tracks, 15 sectors
SET_DH(1); // max head #
break;
case 3: // 720KB, 3.5"
CX = 0x4f09; // 80 tracks, 9 sectors
SET_DH(1); // max head #
break;
case 4: // 1.44MB, 3.5"
CX = 0x4f12; // 80 tracks, 18 sectors
SET_DH(1); // max head #
break;
case 5: // 2.88MB, 3.5"
CX = 0x4f24; // 80 tracks, 36 sectors
SET_DH(1); // max head #
break;
default: // ?
panic("floppy: int13: bad floppy type\n");
}
/* set es & di to point to 11 byte diskette param table */
DI = read_word(0x0000, 0x0078);
ES = read_word(0x0000, 0x007a);
CLEAR_CF(); // success
/* disk status not changed upon success */
return;
case 0x15: // read diskette drive type
printf("floppy f15\n");
drive = GET_DL();
if (drive > 1) {
SET_AH(0); // only 2 drives supported
// set_diskette_ret_status here ???
SET_CF();
return;
}
drive_type = inb_cmos(0x10);
if (drive == 0)
drive_type >>= 4;
else
drive_type &= 0x0f;
CLEAR_CF(); // successful, not present
if (drive_type==0) {
SET_AH(0); // drive not present
}
else {
SET_AH(1); // drive present, does not support change line
}
return;
case 0x16: // get diskette change line status
printf("floppy f16\n");
drive = GET_DL();
if (drive > 1) {
SET_AH(0x01); // invalid drive
set_diskette_ret_status(0x01);
SET_CF();
return;
}
SET_AH(0x06); // change line not supported
set_diskette_ret_status(0x06);
SET_CF();
return;
case 0x17: // set diskette type for format(old)
printf("floppy f17\n");
/* not used for 1.44M floppies */
SET_AH(0x01); // not supported
set_diskette_ret_status(1); /* not supported */
SET_CF();
return;
case 0x18: // set diskette type for format(new)
printf("floppy f18\n");
SET_AH(0x01); // do later
set_diskette_ret_status(1);
SET_CF();
return;
default:
if ( (ah==0x20) || ((ah>=0x41) && (ah<=0x49)) || (ah==0x4e) ) {
SET_AH(0x01); // ???
set_diskette_ret_status(1);
SET_CF();
printf("floppy: int13: 0x%02x\n", ah);
return;
}
panic("int13_diskette: AH=%02x\n", ah);
}
}
#else // #if BX_SUPPORT_FLOPPY
void
int13_diskette_function(DI, SI, BP, SP, BX, DX, CX, AX, ES, FLAGS)
Bit16u DI, SI, BP, SP, BX, DX, CX, AX, ES, FLAGS;
{
Bit8u val8;
switch ( GET_AH() ) {
case 0x01: // Read Diskette Status
CLEAR_CF();
val8 = read_byte(0x0000, 0x0441);
SET_AH(val8);
if (val8) {
SET_CF();
}
return;
default:
SET_CF();
write_byte(0x0000, 0x0441, 0x01);
SET_AH(0x01);
}
}
#endif // #if BX_SUPPORT_FLOPPY
void
set_disk_ret_status(val)
Bit8u val;
{
write_byte(0x0040, 0x0074, val);
}
void
set_diskette_ret_status(value)
Bit8u value;
{
write_byte(0x0040, 0x0041, value);
}
void
set_diskette_current_cyl(drive, cyl)
Bit8u drive;
Bit8u cyl;
{
if (drive > 1)
panic("set_diskette_current_cyl(): drive > 1\n");
write_byte(0x0040, 0x0094+drive, cyl);
}
void
determine_floppy_media(drive)
Bit16u drive;
{
#if 0
Bit8u val8, DOR, ctrl_info;
ctrl_info = read_byte(0x0040, 0x008F);
if (drive==1)
ctrl_info >>= 4;
else
ctrl_info &= 0x0f;
#if 0
if (drive == 0) {
DOR = 0x1c; // DOR: drive0 motor on, DMA&int enabled, normal op, drive select 0
}
else {
DOR = 0x2d; // DOR: drive1 motor on, DMA&int enabled, normal op, drive select 1
}
#endif
if ( (ctrl_info & 0x04) != 0x04 ) {
// Drive not determined means no drive exists, done.
return;
}
#if 0
// check Main Status Register for readiness
val8 = inb(0x03f4) & 0x80; // Main Status Register
if (val8 != 0x80)
panic("d_f_m: MRQ bit not set\n");
// change line
// existing BDA values
// turn on drive motor
outb(0x03f2, DOR); // Digital Output Register
//
#endif
panic("d_f_m: OK so far\n");
#endif
}
void
get_hd_geometry(drive, hd_cylinders, hd_heads, hd_sectors)
Bit8u drive;
Bit16u *hd_cylinders;
Bit8u *hd_heads;
Bit8u *hd_sectors;
{
Bit8u hd_type;
Bit16u ss;
Bit16u cylinders;
Bit8u iobase;
ss = get_SS();
if (drive == 0x80) {
hd_type = inb_cmos(0x12) & 0xf0;
if (hd_type != 0xf0)
panic("HD0 cmos reg 12h not type F\n");
hd_type = inb_cmos(0x19); // HD0: extended type
if (hd_type != 47)
panic("HD0 cmos reg 19h not user definable type 47\n");
iobase = 0x1b;
} else {
hd_type = inb_cmos(0x12) & 0x0f;
if (hd_type != 0x0f)
panic("HD1 cmos reg 12h not type F\n");
hd_type = inb_cmos(0x1a); // HD0: extended type
if (hd_type != 47)
panic("HD1 cmos reg 1ah not user definable type 47\n");
iobase = 0x24;
}
// cylinders
cylinders = inb_cmos(iobase) | (inb_cmos(iobase+1) << 8);
write_word(ss, hd_cylinders, cylinders);
// heads
write_byte(ss, hd_heads, inb_cmos(iobase+2));
// sectors per track
write_byte(ss, hd_sectors, inb_cmos(iobase+8));
}
void
int1a_function(regs, ds, iret_addr)
pusha_regs_t regs; // regs pushed from PUSHA instruction
Bit16u ds; // previous DS:, DS set to 0x0000 by asm wrapper
iret_addr_t iret_addr; // CS,IP,Flags pushed from original INT call
{
Bit8u val8;
#asm
sti
#endasm
switch (regs.u.r8.ah) {
case 0: // get current clock count
#asm
cli
#endasm
regs.u.r16.cx = BiosData->ticks_high;
regs.u.r16.dx = BiosData->ticks_low;
regs.u.r8.al = BiosData->midnight_flag;
BiosData->midnight_flag = 0; // reset flag
#asm
sti
#endasm
// AH already 0
ClearCF(iret_addr.flags); // OK
break;
case 1: // Set Current Clock Count
#asm
cli
#endasm
BiosData->ticks_high = regs.u.r16.cx;
BiosData->ticks_low = regs.u.r16.dx;
BiosData->midnight_flag = 0; // reset flag
#asm
sti
#endasm
regs.u.r8.ah = 0;
ClearCF(iret_addr.flags); // OK
break;
case 2: // Read CMOS Time
if (rtc_updating()) {
SetCF(iret_addr.flags);
break;
}
regs.u.r8.dh = inb_cmos(0x00); // Seconds
regs.u.r8.cl = inb_cmos(0x02); // Minutes
regs.u.r8.ch = inb_cmos(0x04); // Hours
regs.u.r8.dl = inb_cmos(0x0b) & 0x01; // Stat Reg B
regs.u.r8.ah = 0;
regs.u.r8.al = regs.u.r8.ch;
ClearCF(iret_addr.flags); // OK
break;
case 3: // Set CMOS Time
// Using a debugger, I notice the following masking/setting
// of bits in Status Register B, by setting Reg B to
// a few values and getting its value after INT 1A was called.
//
// try#1 try#2 try#3
// before 1111 1101 0111 1101 0000 0000
// after 0110 0010 0110 0010 0000 0010
//
// Bit4 in try#1 flipped in hardware (forced low) due to bit7=1
// My assumption: RegB = ((RegB & 01100000b) | 00000010b)
if (rtc_updating()) {
init_rtc();
// fall through as if an update were not in progress
}
outb_cmos(0x00, regs.u.r8.dh); // Seconds
outb_cmos(0x02, regs.u.r8.cl); // Minutes
outb_cmos(0x04, regs.u.r8.ch); // Hours
// Set Daylight Savings time enabled bit to requested value
val8 = (inb_cmos(0x0b) & 0x60) | 0x02 | (regs.u.r8.dl & 0x01);
// (reg B already selected)
outb_cmos(0x0b, val8);
regs.u.r8.ah = 0;
regs.u.r8.al = val8; // val last written to Reg B
ClearCF(iret_addr.flags); // OK
break;
case 4: // Read CMOS Date
regs.u.r8.ah = 0;
if (rtc_updating()) {
SetCF(iret_addr.flags);
break;
}
regs.u.r8.cl = inb_cmos(0x09); // Year
regs.u.r8.dh = inb_cmos(0x08); // Month
regs.u.r8.dl = inb_cmos(0x07); // Day of Month
regs.u.r8.ch = inb_cmos(0x32); // Century
regs.u.r8.al = regs.u.r8.ch;
ClearCF(iret_addr.flags); // OK
break;
case 5: // Set CMOS Date
// Using a debugger, I notice the following masking/setting
// of bits in Status Register B, by setting Reg B to
// a few values and getting its value after INT 1A was called.
//
// try#1 try#2 try#3 try#4
// before 1111 1101 0111 1101 0000 0010 0000 0000
// after 0110 1101 0111 1101 0000 0010 0000 0000
//
// Bit4 in try#1 flipped in hardware (forced low) due to bit7=1
// My assumption: RegB = (RegB & 01111111b)
if (rtc_updating()) {
init_rtc();
SetCF(iret_addr.flags);
break;
}
outb_cmos(0x09, regs.u.r8.cl); // Year
outb_cmos(0x08, regs.u.r8.dh); // Month
outb_cmos(0x07, regs.u.r8.dl); // Day of Month
outb_cmos(0x32, regs.u.r8.ch); // Century
val8 = inb_cmos(0x0b) & 0x7f; // clear halt-clock bit
outb_cmos(0x0b, val8);
regs.u.r8.ah = 0;
regs.u.r8.al = val8; // AL = val last written to Reg B
ClearCF(iret_addr.flags); // OK
break;
case 6: // Set Alarm Time in CMOS
// Using a debugger, I notice the following masking/setting
// of bits in Status Register B, by setting Reg B to
// a few values and getting its value after INT 1A was called.
//
// try#1 try#2 try#3
// before 1101 1111 0101 1111 0000 0000
// after 0110 1111 0111 1111 0010 0000
//
// Bit4 in try#1 flipped in hardware (forced low) due to bit7=1
// My assumption: RegB = ((RegB & 01111111b) | 00100000b)
val8 = inb_cmos(0x0b); // Get Status Reg B
regs.u.r16.ax = 0;
if (val8 & 0x20) {
// Alarm interrupt enabled already
SetCF(iret_addr.flags); // Error: alarm in use
break;
}
if (rtc_updating()) {
init_rtc();
// fall through as if an update were not in progress
}
outb_cmos(0x01, regs.u.r8.dh); // Seconds alarm
outb_cmos(0x03, regs.u.r8.cl); // Minutes alarm
outb_cmos(0x05, regs.u.r8.ch); // Hours alarm
outb(0xa1, inb(0xa1) & 0xfe); // enable IRQ 8
// enable Status Reg B alarm bit, clear halt clock bit
outb_cmos(0x0b, (val8 & 0x7f) | 0x20);
ClearCF(iret_addr.flags); // OK
break;
case 7: // Turn off Alarm
// Using a debugger, I notice the following masking/setting
// of bits in Status Register B, by setting Reg B to
// a few values and getting its value after INT 1A was called.
//
// try#1 try#2 try#3 try#4
// before 1111 1101 0111 1101 0010 0000 0010 0010
// after 0100 0101 0101 0101 0000 0000 0000 0010
//
// Bit4 in try#1 flipped in hardware (forced low) due to bit7=1
// My assumption: RegB = (RegB & 01010111b)
val8 = inb_cmos(0x0b); // Get Status Reg B
// clear clock-halt bit, disable alarm bit
outb_cmos(0x0b, val8 & 0x57); // disable alarm bit
regs.u.r8.ah = 0;
regs.u.r8.al = val8; // val last written to Reg B
ClearCF(iret_addr.flags); // OK
break;
default:
SetCF(iret_addr.flags); // Unsupported
}
}
void
int70_function(regs, ds, iret_addr)
pusha_regs_t regs; // regs pushed from PUSHA instruction
Bit16u ds; // previous DS:, DS set to 0x0000 by asm wrapper
iret_addr_t iret_addr; // CS,IP,Flags pushed from original INT call
{
// INT 70h: IRQ 8 - CMOS RTC interrupt from periodic or alarm modes
Bit8u val8;
val8 = inb_cmos(0x0c); // Status Reg C
if (val8 == 0) panic("int70: regC 0\n");
if (val8 & 0x40) panic("int70: periodic request\n");
if (val8 & 0x20) {
// Alarm Flag indicates alarm time matches current time
// call user INT 4Ah alarm handler
#asm
sti
//pushf
//;; call_ep [ds:loc]
//CALL_EP( 0x4a << 2 )
int #0x4a
cli
#endasm
}
#asm
;; send EOI to slave & master PICs
mov al, #0x20
out #0xA0, al ;; slave PIC EOI
out #0x20, al ;; master PIC EOI
#endasm
}
#asm
;------------------------------------------
;- INT74h : PS/2 mouse hardware interrupt -
;------------------------------------------
int74_handler:
sti
pusha
push ds ;; save DS
push #0x00 ;; placeholder for status
push #0x00 ;; placeholder for X
push #0x00 ;; placeholder for Y
push #0x00 ;; placeholder for Z
push #0x00 ;; placeholder for make_far_call boolean
call _int74_function
pop cx ;; remove make_far_call from stack
jcxz int74_done
;; make far call to EBDA:0022
push #0x00
pop ds
push 0x040E ;; push 0000:040E (opcodes 0xff, 0x36, 0x0E, 0x04)
pop ds
//CALL_EP(0x0022) ;; call far routine (call_Ep DS:0022 :opcodes 0xff, 0x1e, 0x22, 0x00)
call far ptr[0x22]
int74_done:
cli
mov al, #0x20
;; send EOI to slave & master PICs
out #0xA0, al ;; slave PIC EOI
out #0x20, al ;; master PIC EOI
add sp, #8 ;; pop status, x, y, z
pop ds ;; restore DS
popa
iret
;; This will perform an IRET, but will retain value of current CF
;; by altering flags on stack. Better than RETF #02.
iret_modify_cf:
jc carry_set
push bp
mov bp, sp
and BYTE [bp + 0x06], #0xfe
pop bp
iret
carry_set:
push bp
mov bp, sp
or BYTE [bp + 0x06], #0x01
pop bp
iret
;----------------------
;- INT13h (relocated) -
;----------------------
int13_relocated:
pushf
test dl, #0x80
jz int13_floppy
int13_disk:
;; pushf already done
push es
pusha
call _int13_function
popa
pop es
popf
// JMPL(iret_modify_cf)
jmp iret_modify_cf
int13_floppy:
popf
// JMPL(int13_diskette)
jmp int13_diskette
;----------------------
;- INT19h (relocated) -
;----------------------
int19_relocated:
;; check bit 5 in CMOS reg 0x2d. load either 0x00 or 0x80 into DL
;; in preparation for the intial INT 13h (0=floppy A:, 0x80=C:)
;; 0: system boot sequence, first drive C: then A:
;; 1: system boot sequence, first drive A: then C:
mov al, #0x2d
out 0x70, al
in al, 0x71
and al, #0x20
jz int19_usedisk
int19_usefloppy:
mov dl, #0x00
jmp int19_loadsector
int19_usedisk:
mov dl, #0x80
int19_loadsector:
mov ax, #0x0000
mov es, ax ;; seg = 0000
mov bx, #0x7c00 ;; load boot sector into 0000:7c000
mov ah, #0x02 ;; function 2, read diskette sector
mov al, #0x01 ;; read 1 sector
mov ch, #0x00 ;; track 0
mov cl, #0x01 ;; sector 1
mov dh, #0x00 ;; head 0
int #0x13
jc bootstrap_problem
JMP_AP(0x0000, 0x7c00)
bootstrap_problem:
xor dh,dh
push dx
call _boot_failure_msg
int #0x18 ;; Boot failure
iret
;----------
;- INT18h -
;----------
int18_handler: ;; Boot Failure routing
HALT(__LINE__)
iret
;----------
;- INT1Ch -
;----------
int1c_handler: ;; User Timer Tick
iret
;----------------------
;- POST: Floppy Drive -
;----------------------
floppy_drive_post:
mov ax, #0x0000
mov ds, ax
mov al, #0x00
mov 0x043e, al ;; drive 0 & 1 uncalibrated, no interrupt has occurred
mov 0x043f, al ;; diskette motor status: read op, drive0, motors off
mov 0x0440, al ;; diskette motor timeout counter: not active
mov 0x0441, al ;; diskette controller status return code
mov 0x0442, al ;; disk & diskette controller status register 0
mov 0x0443, al ;; diskette controller status register 1
mov 0x0444, al ;; diskette controller status register 2
mov 0x0445, al ;; diskette controller cylinder number
mov 0x0446, al ;; diskette controller head number
mov 0x0447, al ;; diskette controller sector number
mov 0x0448, al ;; diskette controller bytes written
mov 0x048b, al ;; diskette configuration data
;; -----------------------------------------------------------------
;; (048F) diskette controller information
;;
mov al, #0x10 ;; get CMOS diskette drive type
out 0x70, AL
in AL, 0x71
mov ah, al ;; save byte to AH
look_drive0:
shr al, #4 ;; look at top 4 bits for drive 0
jz f0_missing ;; jump if no drive0
mov bl, #0x07 ;; drive0 determined, multi-rate, has changed line
jmp look_drive1
f0_missing:
mov bl, #0x00 ;; no drive0
look_drive1:
mov al, ah ;; restore from AH
and al, #0x0f ;; look at bottom 4 bits for drive 1
jz f1_missing ;; jump if no drive1
or bl, #0x70 ;; drive1 determined, multi-rate, has changed line
f1_missing:
;; leave high bits in BL zerod
mov 0x048f, bl ;; put new val in BDA (diskette controller information)
;; -----------------------------------------------------------------
mov al, #0x00
mov 0x0490, al ;; diskette 0 media state
mov 0x0491, al ;; diskette 1 media state
;; diskette 0,1 operational starting state
;; drive type has not been determined,
;; has no changed detection line
mov 0x0492, al
mov 0x0493, al
mov 0x0494, al ;; diskette 0 current cylinder
mov 0x0495, al ;; diskette 1 current cylinder
mov al, #0x02
out #0x0a, al ;; clear DMA-1 channel 2 mask bit
SET_INT_VECTOR(0x1E, #0xF000, #diskette_param_table)
SET_INT_VECTOR(0x40, #0xF000, #int13_diskette)
SET_INT_VECTOR(0x0E, #0xF000, #int0e_handler) ;; IRQ 6
ret
;--------------------
;- POST: HARD DRIVE -
;--------------------
; relocated here because the primary POST area isnt big enough.
hard_drive_post:
// IRQ 14 = INT 76h
// INT 76h calls INT 15h function ax=9100
mov al, #0x0a ; 0000 1010 = reserved, disable IRQ 14
mov dx, #0x03f6
out dx, al
mov ax, #0x0000
mov ds, ax
mov 0x0474, al /* hard disk status of last operation */
mov 0x0477, al /* hard disk port offset (XT only ???) */
mov 0x048c, al /* hard disk status register */
mov 0x048d, al /* hard disk error register */
mov 0x048e, al /* hard disk task complete flag */
mov al, #0x01
mov 0x0475, al /* hard disk number attached */
mov al, #0xc0
mov 0x0476, al /* hard disk control byte */
SET_INT_VECTOR(0x13, #0xF000, #int13_handler)
SET_INT_VECTOR(0x76, #0xF000, #int76_handler)
;; INT 41h: hard disk 0 configuration pointer
;; INT 46h: hard disk 1 configuration pointer
SET_INT_VECTOR(0x41, #EBDA_SEG, #0x003D)
SET_INT_VECTOR(0x46, #EBDA_SEG, #0x004D)
;; move disk geometry data from CMOS to EBDA disk parameter table(s)
mov al, #0x12
out #0x70, al
in al, #0x71
and al, #0xf0
cmp al, #0xf0
je post_d0_extended
jmp check_for_hd1
post_d0_extended:
mov al, #0x19
out #0x70, al
in al, #0x71
cmp al, #47 ;; decimal 47 - user definable
je post_d0_type47
HALT(__LINE__)
post_d0_type47:
;; CMOS purpose param table offset
;; 1b cylinders low 0
;; 1c cylinders high 1
;; 1d heads 2
;; 1e write pre-comp low 5
;; 1f write pre-comp high 6
;; 20 retries/bad map/heads>8 8
;; 21 landing zone low C
;; 22 landing zone high D
;; 23 sectors/track E
mov ax, #EBDA_SEG
mov ds, ax
;;; Filling EBDA table for hard disk 0.
mov al, #0x1f
out #0x70, al
in al, #0x71
mov ah, al
mov al, #0x1e
out #0x70, al
in al, #0x71
mov (0x003d + 0x05), ax ;; write precomp word
mov al, #0x20
out #0x70, al
in al, #0x71
mov (0x003d + 0x08), al ;; drive control byte
mov al, #0x22
out #0x70, al
in al, #0x71
mov ah, al
mov al, #0x21
out #0x70, al
in al, #0x71
mov (0x003d + 0x0C), ax ;; landing zone word
mov al, #0x1c ;; get cylinders word in AX
out #0x70, al
in al, #0x71 ;; high byte
mov ah, al
mov al, #0x1b
out #0x70, al
in al, #0x71 ;; low byte
mov bx, ax ;; BX = cylinders
mov al, #0x1d
out #0x70, al
in al, #0x71
mov cl, al ;; CL = heads
mov al, #0x23
out #0x70, al
in al, #0x71
mov dl, al ;; DL = sectors
cmp bx, #1024
jnbe hd0_post_logical_chs ;; if cylinders > 1024, use translated style CHS
hd0_post_physical_chs:
;; no logical CHS mapping used, just physical CHS
;; use Standard Fixed Disk Parameter Table (FDPT)
mov (0x003d + 0x00), bx ;; number of physical cylinders
mov (0x003d + 0x02), cl ;; number of physical heads
mov (0x003d + 0x0E), dl ;; number of physical sectors
jmp check_for_hd1
hd0_post_logical_chs:
;; complies with Phoenix style Translated Fixed Disk Parameter Table (FDPT)
mov (0x003d + 0x09), bx ;; number of physical cylinders
mov (0x003d + 0x0b), cl ;; number of physical heads
mov (0x003d + 0x04), dl ;; number of physical sectors
mov (0x003d + 0x0e), dl ;; number of logical sectors (same)
mov al, #0xa0
mov (0x003d + 0x03), al ;; A0h signature, indicates translated table
cmp bx, #2048
jnbe hd0_post_above_2048
;; 1024 < c <= 2048 cylinders
shr bx, #0x01
shl cl, #0x01
jmp hd0_post_store_logical
hd0_post_above_2048:
cmp bx, #4096
jnbe hd0_post_above_4096
;; 2048 < c <= 4096 cylinders
shr bx, #0x02
shl cl, #0x02
jmp hd0_post_store_logical
hd0_post_above_4096:
cmp bx, #8192
jnbe hd0_post_above_8192
;; 4096 < c <= 8192 cylinders
shr bx, #0x03
shl cl, #0x03
jmp hd0_post_store_logical
hd0_post_above_8192:
;; 8192 < c <= 16384 cylinders
shr bx, #0x04
shl cl, #0x04
hd0_post_store_logical:
mov (0x003d + 0x00), bx ;; number of physical cylinders
mov (0x003d + 0x02), cl ;; number of physical heads
;; checksum
mov cl, #0x0f ;; repeat count
mov si, #0x003d ;; offset to disk0 FDPT
mov al, #0x00 ;; sum
hd0_post_checksum_loop:
add al, [si]
inc si
dec cl
jnz hd0_post_checksum_loop
not al ;; now take 2s complement
inc al
mov [si], al
;;; Done filling EBDA table for hard disk 0.
check_for_hd1:
;; is there really a second hard disk? if not, return now
mov al, #0x12
out #0x70, al
in al, #0x71
and al, #0x0f
jnz post_d1_exists
ret
post_d1_exists:
;; check that the hd type is really 0x0f.
cmp al, #0x0f
jz post_d1_extended
HALT(__LINE__)
post_d1_extended:
;; check that the extended type is 47 - user definable
mov al, #0x1a
out #0x70, al
in al, #0x71
cmp al, #47 ;; decimal 47 - user definable
je post_d1_type47
HALT(__LINE__)
post_d1_type47:
;; Table for disk1.
;; CMOS purpose param table offset
;; 0x24 cylinders low 0
;; 0x25 cylinders high 1
;; 0x26 heads 2
;; 0x27 write pre-comp low 5
;; 0x28 write pre-comp high 6
;; 0x29 heads>8 8
;; 0x2a landing zone low C
;; 0x2b landing zone high D
;; 0x2c sectors/track E
;;; Fill EBDA table for hard disk 1.
mov al, #0x28
out #0x70, al
in al, #0x71
mov ah, al
mov al, #0x27
out #0x70, al
in al, #0x71
mov (0x004d + 0x05), ax ;; write precomp word
mov al, #0x29
out #0x70, al
in al, #0x71
mov (0x004d + 0x08), al ;; drive control byte
mov al, #0x2b
out #0x70, al
in al, #0x71
mov ah, al
mov al, #0x2a
out #0x70, al
in al, #0x71
mov (0x004d + 0x0C), ax ;; landing zone word
mov al, #0x25 ;; get cylinders word in AX
out #0x70, al
in al, #0x71 ;; high byte
mov ah, al
mov al, #0x24
out #0x70, al
in al, #0x71 ;; low byte
mov bx, ax ;; BX = cylinders
mov al, #0x26
out #0x70, al
in al, #0x71
mov cl, al ;; CL = heads
mov al, #0x2c
out #0x70, al
in al, #0x71
mov dl, al ;; DL = sectors
cmp bx, #1024
jnbe hd1_post_logical_chs ;; if cylinders > 1024, use translated style CHS
hd1_post_physical_chs:
;; no logical CHS mapping used, just physical CHS
;; use Standard Fixed Disk Parameter Table (FDPT)
mov (0x004d + 0x00), bx ;; number of physical cylinders
mov (0x004d + 0x02), cl ;; number of physical heads
mov (0x004d + 0x0E), dl ;; number of physical sectors
ret
hd1_post_logical_chs:
;; complies with Phoenix style Translated Fixed Disk Parameter Table (FDPT)
mov (0x004d + 0x09), bx ;; number of physical cylinders
mov (0x004d + 0x0b), cl ;; number of physical heads
mov (0x004d + 0x04), dl ;; number of physical sectors
mov (0x004d + 0x0e), dl ;; number of logical sectors (same)
mov al, #0xa0
mov (0x004d + 0x03), al ;; A0h signature, indicates translated table
cmp bx, #2048
jnbe hd1_post_above_2048
;; 1024 < c <= 2048 cylinders
shr bx, #0x01
shl cl, #0x01
jmp hd1_post_store_logical
hd1_post_above_2048:
cmp bx, #4096
jnbe hd1_post_above_4096
;; 2048 < c <= 4096 cylinders
shr bx, #0x02
shl cl, #0x02
jmp hd1_post_store_logical
hd1_post_above_4096:
cmp bx, #8192
jnbe hd1_post_above_8192
;; 4096 < c <= 8192 cylinders
shr bx, #0x03
shl cl, #0x03
jmp hd1_post_store_logical
hd1_post_above_8192:
;; 8192 < c <= 16384 cylinders
shr bx, #0x04
shl cl, #0x04
hd1_post_store_logical:
mov (0x004d + 0x00), bx ;; number of physical cylinders
mov (0x004d + 0x02), cl ;; number of physical heads
;; checksum
mov cl, #0x0f ;; repeat count
mov si, #0x004d ;; offset to disk0 FDPT
mov al, #0x00 ;; sum
hd1_post_checksum_loop:
add al, [si]
inc si
dec cl
jnz hd1_post_checksum_loop
not al ;; now take 2s complement
inc al
mov [si], al
;;; Done filling EBDA table for hard disk 0.
ret
BcdToBin:
;; in: AL in BCD format
;; out: AL in binary format, AH will always be 0
;; trashes BX
mov bl, al
and bl, #0x0f ;; bl has low digit
shr al, #4 ;; al has high digit
mov bh, #10
mul al, bh ;; multiply high digit by 10 (result in AX)
add al, bl ;; then add low digit
ret
timer_tick_post:
;; Setup the Timer Ticks Count (0x46C:dword) and
;; Timer Ticks Roller Flag (0x470:byte)
;; The Timer Ticks Count needs to be set according to
;; the current CMOS time, as if ticks have been occurring
;; at 18.2hz since midnight up to this point. Calculating
;; this is a little complicated. Here are the factors I gather
;; regarding this. 14,318,180 hz was the original clock speed,
;; chosen so it could be divided by either 3 to drive the 5Mhz CPU
;; at the time, or 4 to drive the CGA video adapter. The div3
;; source was divided again by 4 to feed a 1.193Mhz signal to
;; the timer. With a maximum 16bit timer count, this is again
;; divided down by 65536 to 18.2hz.
;;
;; 14,318,180 Hz clock
;; /3 = 4,772,726 Hz fed to orginal 5Mhz CPU
;; /4 = 1,193,181 Hz fed to timer
;; /65536 (maximum timer count) = 18.20650736 ticks/second
;; 1 second = 18.20650736 ticks
;; 1 minute = 1092.390442 ticks
;; 1 hour = 65543.42651 ticks
;;
;; Given the values in the CMOS clock, one could calculate
;; the number of ticks by the following:
;; ticks = (BcdToBin(seconds) * 18.206507) +
;; (BcdToBin(minutes) * 1092.3904)
;; (BcdToBin(hours) * 65543.427)
;; To get a little more accuracy, since Im using integer
;; arithmatic, I use:
;; ticks = (BcdToBin(seconds) * 18206507) / 1000000 +
;; (BcdToBin(minutes) * 10923904) / 10000 +
;; (BcdToBin(hours) * 65543427) / 1000
;; assuming DS=0000
;; get CMOS seconds
xor eax, eax ;; clear EAX
mov al, #0x00
out #0x70, al
in al, #0x71 ;; AL has CMOS seconds in BCD
call BcdToBin ;; EAX now has seconds in binary
mov edx, #18206507
mul eax, edx
mov ebx, #1000000
xor edx, edx
div eax, ebx
mov ecx, eax ;; ECX will accumulate total ticks
;; get CMOS minutes
xor eax, eax ;; clear EAX
mov al, #0x02
out #0x70, al
in al, #0x71 ;; AL has CMOS minutes in BCD
call BcdToBin ;; EAX now has minutes in binary
mov edx, #10923904
mul eax, edx
mov ebx, #10000
xor edx, edx
div eax, ebx
add ecx, eax ;; add to total ticks
;; get CMOS hours
xor eax, eax ;; clear EAX
mov al, #0x04
out #0x70, al
in al, #0x71 ;; AL has CMOS hours in BCD
call BcdToBin ;; EAX now has hours in binary
mov edx, #65543427
mul eax, edx
mov ebx, #1000
xor edx, edx
div eax, ebx
add ecx, eax ;; add to total ticks
mov 0x46C, ecx ;; Timer Ticks Count
xor al, al
mov 0x470, al ;; Timer Ticks Rollover Flag
ret
int76_handler:
;; record completion in BIOS task complete flag
push ax
push ds
mov ax, #0x0040
mov ds, ax
mov 0x008E, #0xff
mov al, #0x20
out #0xA0, al ;; slave PIC EOI
out #0x20, al ;; master PIC EOI
pop ds
pop ax
iret
;; for 'C' strings and other data, insert them here with
;; a the following hack:
;; DATA_SEG_DEFS_HERE
;--------
;- POST -
;--------
.org 0xe05b ; POST Entry Point
post:
;; Examine CMOS shutdown status.
;; 0 = normal startup
mov AL, #0x0f
out 0x70, AL
in AL, 0x71
cmp AL, #0x00
jz normal_post
HALT(__LINE__)
;
mov AL, #0x0f
out 0x70, AL ; select CMOS register Fh
mov AL, #0x00
out 0x71, AL ; set shutdown action to normal
;
;#if 0
; 0xb0, 0x20, /* mov al, #0x20 */
; 0xe6, 0x20, /* out 0x20, al ;send EOI to PIC */
;#endif
;
pop es
pop ds
popa
iret
normal_post:
; case 0: normal startup
cli
mov ax, #0xfffe
mov sp, ax
mov ax, #0x0000
mov ds, ax
mov ss, ax
;; zero out BIOS data area (40:00..40:ff)
mov es, ax
mov cx, #0x0080 ;; 128 words
mov di, #0x0400
cld
rep
stosw
;; set all interrupts to default handler
mov bx, #0x0000 ;; offset index
mov cx, #0x0100 ;; counter (256 interrupts)
mov ax, #dummy_iret_handler
mov dx, #0xF000
post_default_ints:
mov [bx], ax
inc bx
inc bx
mov [bx], dx
inc bx
inc bx
loop post_default_ints
;; base memory in K 40:13 (word)
mov ax, #BASE_MEM_IN_K
mov 0x0413, ax
;; Manufacturing Test 40:12
;; zerod out above
;; Warm Boot Flag 0040:0072
;; value of 1234h = skip memory checks
;; zerod out above
;; Printer Services vector
SET_INT_VECTOR(0x17, #0xF000, #int17_handler)
;; Bootstrap failure vector
SET_INT_VECTOR(0x18, #0xF000, #int18_handler)
;; Bootstrap Loader vector
SET_INT_VECTOR(0x19, #0xF000, #int19_handler)
;; User Timer Tick vector
SET_INT_VECTOR(0x1c, #0xF000, #int1c_handler)
;; Memory Size Check vector
SET_INT_VECTOR(0x12, #0xF000, #int12_handler)
;; Equipment Configuration Check vector
SET_INT_VECTOR(0x11, #0xF000, #int11_handler)
;; System Services
SET_INT_VECTOR(0x15, #0xF000, #int15_handler)
mov ax, #0x0000 ; mov EBDA seg into 40E
mov ds, ax
mov 0x40E, #EBDA_SEG
;; PIT setup
SET_INT_VECTOR(0x08, #0xF000, #int08_handler)
;; int 1C already points at dummy_iret_handler (above)
mov al, #0x34 ; timer0: binary count, 16bit count, mode 2
out 0x43, al
mov al, #0x00 ; maximum count of 0000H = 18.2Hz
out 0x40, al
out 0x40, al
;; Keyboard
SET_INT_VECTOR(0x09, #0xF000, #int09_handler)
SET_INT_VECTOR(0x16, #0xF000, #int16_handler)
mov ax, #0x0000
mov ds, ax
mov 0x0417, al /* keyboard shift flags, set 1 */
mov 0x0418, al /* keyboard shift flags, set 2 */
mov 0x0419, al /* keyboard alt-numpad work area */
mov 0x0471, al /* keyboard ctrl-break flag */
mov 0x0496, al /* keyboard status flags 3 */
mov 0x0497, al /* keyboard status flags 4 */
/* keyboard head of buffer pointer */
mov bx, #0x001E
mov 0x041A, bx
/* keyboard end of buffer pointer */
mov 0x041C, bx
/* keyboard buffer */
// for (i=0; i<16; i++)
// bx_mem.access_physical(0x41E + i*2, 2, BX_WRITE, &zero16);
/* keyboard pointer to start of buffer */
mov bx, #0x001E
mov 0x0480, bx
/* keyboard pointer to end of buffer */
mov bx, #0x003E
mov 0x0482, bx
/* (mch) Keyboard self-test */
mov al, #0xaa
out 0x64, al
in al, 0x60
cmp al, #0x55
je keyboard_ok
call _keyboard_panic
keyboard_ok:
#if BX_USE_PS2_MOUSE
in al, 0xa1
and al, #0xef
out 0xa1, al
// hack to tell CMOS & BIOS data area that we have a mouse
mov al, #0x14
out 0x70, al
in al, 0x71
or al, #0x04
out 0x71, al
#endif
;; mov CMOS Equipment Byte to BDA Equipment Word
mov ax, 0x0410
mov al, #0x14
out 0x70, al
in al, 0x71
mov 0x0410, ax
;; DMA
;; nothing for now
;; Parallel setup
SET_INT_VECTOR(0x0F, #0xF000, #dummy_iret_handler)
mov ax, #0x0000
mov ds, ax
mov 0x408, AX ; Parallel I/O address, port 1
mov 0x40A, AX ; Parallel I/O address, port 2
mov 0x40C, AX ; Parallel I/O address, port 3
mov 0x478, AL ; Parallel printer 1 timeout
mov 0x479, AL ; Parallel printer 2 timerout
mov 0x47A, AL ; Parallel printer 3 timerout
mov 0x47B, AL ; Parallel printer 4 timerout
;; Serial setup
SET_INT_VECTOR(0x0C, #0xF000, #dummy_iret_handler)
SET_INT_VECTOR(0x14, #0xF000, #int14_handler)
;; assuming AX==0, DS==0 from above
mov 0x400, AX ; Serial I/O address, port 1
mov 0x402, AX ; Serial I/O address, port 2
mov 0x404, AX ; Serial I/O address, port 3
mov 0x406, AX ; Serial I/O address, port 4
mov 0x47C, AL ; Serial 1 timeout
mov 0x47D, AL ; Serial 2 timeout
mov 0x47E, AL ; Serial 3 timeout
mov 0x47F, AL ; Serial 4 timeout
mov AX, 0x410 ; Equipment word bits 9..11 determing # serial ports
and AX, #0xf1ff ; clear bits 9..11 for now (zero ports)
mov 0x410, AX
;; CMOS RTC
SET_INT_VECTOR(0x1A, #0xF000, #int1a_handler)
SET_INT_VECTOR(0x4A, #0xF000, #dummy_iret_handler)
SET_INT_VECTOR(0x70, #0xF000, #int70_handler)
;; BIOS DATA AREA 0x4CE ???
call timer_tick_post
;; PS/2 mouse setup
SET_INT_VECTOR(0x74, #0xF000, #int74_handler)
;; Video setup
SET_INT_VECTOR(0x10, #0xF000, #int10_handler)
;; Call extension ROMs - scan C0000 to F4000 in 800 steps
mov bx, #0xc000
romscan:
mov ds, bx
mov ax, 0x0000
cmp ax, #0xAA55
jne notrom
xor ax,ax
mov ds,ax
push bx
push #3
mov bp,sp
db 0xff ; call 0[bp]
db 0x5e
db 0
pop ax
pop bx
notrom:
add bx,#0x80
cmp bx,#0xf400
jne romscan
xor ax,ax
mov ds,ax
;; PIC
mov al, #0x00
out 0x21, AL ;master pic: all IRQs unmasked
out 0xA1, AL ;slave pic: all IRQs unmasked
;;
;; Hard Drive setup
;;
call hard_drive_post
;;
;; Floppy setup
;;
call floppy_drive_post
call _print_bios_banner
int #0x19
//JMP_EP(0x0064) ; INT 19h location
.org 0xe2c3 ; NMI Handler Entry Point
call _nmi_handler_msg
HALT(__LINE__)
iret
;-------------------------------------------
;- INT 13h Fixed Disk Services Entry Point -
;-------------------------------------------
.org 0xe3fe ; INT 13h Fixed Disk Services Entry Point
int13_handler:
//JMPL(int13_relocated)
jmp int13_relocated
.org 0xe401 ; Fixed Disk Parameter Table
;----------
;- INT19h -
;----------
.org 0xe6f2 ; INT 19h Boot Load Service Entry Point
int19_handler:
//JMPL(int19_relocated)
jmp int19_relocated
;-------------------------------------------
;- System BIOS Configuration Data Table
;-------------------------------------------
.org BIOS_CONFIG_TABLE
db 0x08 ; Table size (bytes) -Lo
db 0x00 ; Table size (bytes) -Hi
db SYS_MODEL_ID
db SYS_SUBMODEL_ID
db BIOS_REVISION
; Feature byte 1
; b7: 1=DMA channel 3 used by hard disk
; b6: 1=2 interrupt controllers present
; b5: 1=RTC present
; b4: 1=BIOS calls int 15h/4Fh every key
; b3: 1=wait for extern event supported (Int 15h/41h)
; b2: 1=extended BIOS data area used
; b1: 0=AT or ESDI bus, 1=MicroChannel
; b0: 1=Dual bus (MicroChannel + ISA)
db (0 << 7) | \
(1 << 6) | \
(1 << 5) | \
(BX_CALL_INT15_4F << 4) | \
(0 << 3) | \
(BX_USE_EBDA << 2) | \
(0 << 1) | \
(0 << 0)
; Feature byte 2
; b7: 1=32-bit DMA supported
; b6: 1=int16h, function 9 supported
; b5: 1=int15h/C6h (get POS data) supported
; b4: 1=int15h/C7h (get mem map info) supported
; b3: 1=int15h/C8h (en/dis CPU) supported
; b2: 1=non-8042 kb controller
; b1: 1=data streaming supported
; b0: reserved
db 0x00
; Feature byte 3
; b7: not used
; b6: reserved
; b5: reserved
; b4: POST supports ROM-to-RAM enable/disable
; b3: SCSI on system board
; b2: info panel installed
; b1: Initial Machine Load (IML) system - BIOS on disk
; b0: SCSI supported in IML
db 0x00
; Feature byte 4
; b7: IBM private
; b6: EEPROM present
; b5-3: ABIOS presence (011 = not supported)
; b2: private
; b1: memory split above 16Mb supported
; b0: POSTEXT directly supported by POST
db 0x00
; Feature byte 5 (IBM)
; b1: enhanced mouse
; b0: flash EPROM
db 0x00
.org 0xe729 ; Baud Rate Generator Table
;----------
;- INT14h -
;----------
.org 0xe739 ; INT 14h Serial Communications Service Entry Point
int14_handler:
;; ??? should post message here
iret
;----------------------------------------
;- INT 16h Keyboard Service Entry Point -
;----------------------------------------
.org 0xe82e
int16_handler:
push ds
pushf
pusha
cmp ah, #0x00
je int16_F00
mov bx, #0xf000
mov ds, bx
call _int16_function
popa
popf
pop ds
jz int16_zero_set
int16_zero_clear:
push bp
mov bp, sp
//SEG SS
and BYTE [bp + 0x06], #0xbf
pop bp
iret
int16_zero_set:
push bp
mov bp, sp
//SEG SS
or BYTE [bp + 0x06], #0x40
pop bp
iret
int16_F00:
mov bx, #0x0040
mov ds, bx
int16_wait_for_key:
cli
mov bx, 0x001a
cmp bx, 0x001c
jne int16_key_found
sti
nop
#if 0
/* no key yet, call int 15h, function AX=9002 */
0x50, /* push AX */
0xb8, 0x02, 0x90, /* mov AX, #0x9002 */
0xcd, 0x15, /* int 15h */
0x58, /* pop AX */
0xeb, 0xea, /* jmp WAIT_FOR_KEY */
#endif
jmp int16_wait_for_key
int16_key_found:
mov bx, #0xf000
mov ds, bx
call _int16_function
popa
popf
pop ds
#if 0
/* notify int16 complete w/ int 15h, function AX=9102 */
0x50, /* push AX */
0xb8, 0x02, 0x91, /* mov AX, #0x9102 */
0xcd, 0x15, /* int 15h */
0x58, /* pop AX */
#endif
iret
;-------------------------------------------------
;- INT09h : Keyboard Harware Service Entry Point -
;-------------------------------------------------
.org 0xe987
int09_handler:
cli
push ax
mov al, #0xAD ;;disable keyboard
out #0x64, al
sti
;; see if there is really a key to read from the controller
in al, #0x64
test al, #0x01
jz int09_done ;; nope, skip processing
in al, #0x60 ;;read key from keyboard controller
//test al, #0x80 ;;look for key release
//jnz int09_process_key ;; dont pass releases to intercept?
#ifdef BX_CALL_INT15_4F
mov ah, #0x4f ;; allow for keyboard intercept
stc
int #0x15
jnc int09_done
#endif
//int09_process_key:
push ds
pusha
mov bx, #0xf000
mov ds, bx
call _int09_function
popa
pop ds
int09_done:
cli
;; look at PIC in-service-register to see if EOI required
mov al, #0x0B
out #0x20, al
in al, #0x20
and al, #0x02 ;; IRQ 1 in service
jz int09_finish
mov al, #0x20 ;; send EOI to master PIC
out #0x20, al
int09_finish:
mov al, #0xAE ;;enable keyboard
out #0x64, al
pop ax
iret
;----------------------------------------
;- INT 13h Diskette Service Entry Point -
;----------------------------------------
.org 0xec59
int13_diskette:
pushf
push es
pusha
call _int13_diskette_function
popa
pop es
popf
//JMPL(iret_modify_cf)
jmp iret_modify_cf
#if 0
pushf
cmp ah, #0x01
je i13d_f01
;; pushf already done
push es
pusha
call _int13_diskette_function
popa
pop es
popf
//JMPL(iret_modify_cf)
jmp iret_modify_cf
i13d_f01:
popf
push ds
push bx
mov bx, #0x0000
mov ds, bx
mov ah, 0x0441
pop bx
pop ds
clc
;; ??? dont know if this service changes the return status
//JMPL(iret_modify_cf)
jmp iret_modify_cf
#endif
;---------------------------------------------
;- INT 0Eh Diskette Hardware ISR Entry Point -
;---------------------------------------------
.org 0xef57 ; INT 0Eh Diskette Hardware ISR Entry Point
int0e_handler:
push ax
push ds
mov ax, #0x0000 ;; segment 0000
mov ds, ax
mov al, #0x20
out 0x20, al ;; send EOI to PIC
mov al, 0x043e
or al, #0x80 ;; diskette interrupt has occurred
mov 0x043e, al
pop ds
pop ax
iret
.org 0xefc7 ; Diskette Controller Parameter Table
diskette_param_table:
;; Since no provisions are made for multiple drive types, most
;; values in this table are ignored. I set parameters for 1.44M
;; floppy here
db 0xAF
db 0x02 ;; head load time 0000001, DMA used
db 0x25
db 0x02
db 18
db 0x1B
db 0xFF
db 0x6C
db 0xF6
db 0x0F
db 0x01 ;; most systems default to 8
;----------------------------------------
;- INT17h : Printer Service Entry Point -
;----------------------------------------
.org 0xefd2
int17_handler:
iret ;; for now...
.org 0xf045 ; INT 10 Functions 0-Fh Entry Point
HALT(__LINE__)
iret
;----------
;- INT10h -
;----------
.org 0xf065 ; INT 10h Video Support Service Entry Point
int10_handler:
;; dont do anything, since the VGA BIOS handles int10h requests
iret
.org 0xf0a4 ; MDA/CGA Video Parameter Table (INT 1Dh)
;----------
;- INT12h -
;----------
.org 0xf841 ; INT 12h Memory Size Service Entry Point
; ??? different for Pentium (machine check)?
int12_handler:
push ds
mov ax, #0x0040
mov ds, ax
mov ax, 0x0013
pop ds
iret
;----------
;- INT11h -
;----------
.org 0xf84d ; INT 11h Equipment List Service Entry Point
int11_handler:
push ds
mov ax, #0x0040
mov ds, ax
mov ax, 0x0010
pop ds
iret
;----------
;- INT15h -
;----------
.org 0xf859 ; INT 15h System Services Entry Point
int15_handler:
pushf
push ds
push es
pusha
call _int15_function
popa
pop es
pop ds
popf
//JMPL(iret_modify_cf)
jmp iret_modify_cf
;; Protected mode IDT descriptor
;;
;; I just make the limit 0, so the machine will shutdown
;; if an exception occurs during protected mode memory
;; transfers.
;;
;; Set base to f0000 to correspond to beginning of BIOS,
;; in case I actually define an IDT later
;; Set limit to 0
pmode_IDT_info:
dw 0x0000 ;; limit 15:00
dw 0x0000 ;; base 15:00
db 0x0f ;; base 23:16
;; Real mode IDT descriptor
;;
;; Set to typical real-mode values.
;; base = 000000
;; limit = 03ff
rmode_IDT_info:
dw 0x03ff ;; limit 15:00
dw 0x0000 ;; base 15:00
db 0x00 ;; base 23:16
.org 0xfa6e ; Character Font for 320x200 & 640x200 Graphics (lower 128 characters)
;----------
;- INT1Ah -
;----------
.org 0xfe6e ; INT 1Ah Time-of-day Service Entry Point
int1a_handler:
push ds
pusha
mov ax, #0x0000
mov ds, ax
call _int1a_function
popa
pop ds
iret
;;
;; int70h: IRQ8 - CMOS RTC
;;
int70_handler:
push ds
pusha
mov ax, #0x0000
mov ds, ax
call _int70_function
popa
pop ds
iret
;---------
;- INT08 -
;---------
.org 0xfea5 ; INT 08h System Timer ISR Entry Point
int08_handler:
sti
push eax
push ds
mov ax, #0x0000
mov ds, ax
mov eax, 0x046c ;; get ticks dword
inc eax
;; compare eax to one days worth of timer ticks at 18.2 hz
cmp eax, #0x001800B0
jb int08_store_ticks
;; there has been a midnight rollover at this point
xor eax, eax ;; zero out counter
inc BYTE 0x0470 ;; increment rollover flag
int08_store_ticks:
mov 0x046c, eax ;; store new ticks dword
;; chain to user timer tick INT #0x1c
//pushf
//;; call_ep [ds:loc]
//CALL_EP( 0x1c << 2 )
int #0x1c
cli
mov al, #0x20
out 0x20, al ; send EOI to PIC
pop ds
pop eax
iret
.org 0xfef3 ; Initial Interrupt Vector Offsets Loaded by POST
;------------------------------------------------
;- IRET Instruction for Dummy Interrupt Handler -
;------------------------------------------------
.org 0xff53 ; IRET Instruction for Dummy Interrupt Handler
dummy_iret_handler:
iret
.org 0xff54 ; INT 05h Print Screen Service Entry Point
HALT(__LINE__)
iret
; .org 0xff00
; .ascii "(c) 1994-2000 Kevin P. Lawton"
.org 0xfff0 ; Power-up Entry Point
//JMPL(post)
jmp post
.org 0xfff5 ; ASCII Date ROM was built - 8 characters in MM/DD/YY
.ascii "06/23/99"
.org 0xfffe ; System Model ID
db SYS_MODEL_ID
db 0x00 ; filler
.org 0xd000
// bcc-generated data will be placed here
// For documentation of this config structure, look on developer.intel.com and
// search for multiprocessor specification. Note that when you change anything
// you must update the checksum (a pain!). It would be better to construct this
// with C structures, or at least fill in the checksum automatically.
#if (BX_SMP_PROCESSORS==1)
// no structure necessary.
#elif (BX_SMP_PROCESSORS==2)
// define the Intel MP Configuration Structure for 2 processors at
// APIC ID 0,1. I/O APIC at ID=2.
.align 16
mp_config_table:
db 0x50, 0x43, 0x4d, 0x50 ;; "PCMP" signature
dw (mp_config_end-mp_config_table) ;; table length
db 4 ;; spec rev
db 0x65 ;; checksum
.ascii "BOCHSCPU" ;; OEM id = "BOCHSCPU"
db 0x30, 0x2e, 0x31, 0x20 ;; vendor id = "0.1 "
db 0x20, 0x20, 0x20, 0x20
db 0x20, 0x20, 0x20, 0x20
dw 0,0 ;; oem table ptr
dw 0 ;; oem table size
dw 20 ;; entry count
dw 0x0000, 0xfee0 ;; memory mapped address of local APIC
dw 0 ;; extended table length
db 0 ;; extended table checksum
db 0 ;; reserved
mp_config_proc0:
db 0 ;; entry type=processor
db 0 ;; local APIC id
db 0x11 ;; local APIC version number
db 3 ;; cpu flags: enabled
db 0,6,0,0 ;; cpu signature
dw 0x201,0 ;; feature flags
dw 0,0 ;; reserved
dw 0,0 ;; reserved
mp_config_proc1:
db 0 ;; entry type=processor
db 1 ;; local APIC id
db 0x11 ;; local APIC version number
db 1 ;; cpu flags: enabled
db 0,6,0,0 ;; cpu signature
dw 0x201,0 ;; feature flags
dw 0,0 ;; reserved
dw 0,0 ;; reserved
mp_config_isa_bus:
db 1 ;; entry type=bus
db 0 ;; bus ID
db 0x49, 0x53, 0x41, 0x20, 0x20, 0x20 ;; bus type="ISA "
mp_config_ioapic:
db 2 ;; entry type=I/O APIC
db 2 ;; apic id=2. linux will set.
db 0x11 ;; I/O APIC version number
db 1 ;; flags=1=enabled
dw 0x0000, 0xfec0 ;; memory mapped address of I/O APIC
mp_config_irqs:
db 3 ;; entry type=I/O interrupt
db 0 ;; interrupt type=vectored interrupt
db 0,0 ;; flags po=0, el=0 (linux uses as default)
db 0 ;; source bus ID is ISA
db 0 ;; source bus IRQ
db 2 ;; destination I/O APIC ID
db 0 ;; destination I/O APIC interrrupt in
;; repeat pattern for interrupts 0-15
db 3,0,0,0,0,1,2,1
db 3,0,0,0,0,2,2,2
db 3,0,0,0,0,3,2,3
db 3,0,0,0,0,4,2,4
db 3,0,0,0,0,5,2,5
db 3,0,0,0,0,6,2,6
db 3,0,0,0,0,7,2,7
db 3,0,0,0,0,8,2,8
db 3,0,0,0,0,9,2,9
db 3,0,0,0,0,10,2,10
db 3,0,0,0,0,11,2,11
db 3,0,0,0,0,12,2,12
db 3,0,0,0,0,13,2,13
db 3,0,0,0,0,14,2,14
db 3,0,0,0,0,15,2,15
#elif (BX_SMP_PROCESSORS==4)
// define the Intel MP Configuration Structure for 4 processors at
// APIC ID 0,1,2,3. I/O APIC at ID=4.
.align 16
mp_config_table:
db 0x50, 0x43, 0x4d, 0x50 ;; "PCMP" signature
dw (mp_config_end-mp_config_table) ;; table length
db 4 ;; spec rev
db 0xdd ;; checksum
.ascii "BOCHSCPU" ;; OEM id = "BOCHSCPU"
db 0x30, 0x2e, 0x31, 0x20 ;; vendor id = "0.1 "
db 0x20, 0x20, 0x20, 0x20
db 0x20, 0x20, 0x20, 0x20
dw 0,0 ;; oem table ptr
dw 0 ;; oem table size
dw 22 ;; entry count
dw 0x0000, 0xfee0 ;; memory mapped address of local APIC
dw 0 ;; extended table length
db 0 ;; extended table checksum
db 0 ;; reserved
mp_config_proc0:
db 0 ;; entry type=processor
db 0 ;; local APIC id
db 0x11 ;; local APIC version number
db 1 ;; cpu flags: enabled
db 0,6,0,0 ;; cpu signature
dw 0x201,0 ;; feature flags
dw 0,0 ;; reserved
dw 0,0 ;; reserved
mp_config_proc1:
db 0 ;; entry type=processor
db 1 ;; local APIC id
db 0x11 ;; local APIC version number
db 1 ;; cpu flags: enabled
db 0,6,0,0 ;; cpu signature
dw 0x201,0 ;; feature flags
dw 0,0 ;; reserved
dw 0,0 ;; reserved
mp_config_proc2:
db 0 ;; entry type=processor
db 2 ;; local APIC id
db 0x11 ;; local APIC version number
db 3 ;; cpu flags: enabled, bootstrap processor
db 0,6,0,0 ;; cpu signature
dw 0x201,0 ;; feature flags
dw 0,0 ;; reserved
dw 0,0 ;; reserved
mp_config_proc3:
db 0 ;; entry type=processor
db 3 ;; local APIC id
db 0x11 ;; local APIC version number
db 1 ;; cpu flags: enabled
db 0,6,0,0 ;; cpu signature
dw 0x201,0 ;; feature flags
dw 0,0 ;; reserved
dw 0,0 ;; reserved
mp_config_isa_bus:
db 1 ;; entry type=bus
db 0 ;; bus ID
db 0x49, 0x53, 0x41, 0x20, 0x20, 0x20 ;; bus type="ISA "
mp_config_ioapic:
db 2 ;; entry type=I/O APIC
db 4 ;; apic id=2. linux will set.
db 0x11 ;; I/O APIC version number
db 1 ;; flags=1=enabled
dw 0x0000, 0xfec0 ;; memory mapped address of I/O APIC
mp_config_irqs:
db 3 ;; entry type=I/O interrupt
db 0 ;; interrupt type=vectored interrupt
db 0,0 ;; flags po=0, el=0 (linux uses as default)
db 0 ;; source bus ID is ISA
db 0 ;; source bus IRQ
db 4 ;; destination I/O APIC ID
db 0 ;; destination I/O APIC interrrupt in
;; repeat pattern for interrupts 0-15
db 3,0,0,0,0,1,4,1
db 3,0,0,0,0,2,4,2
db 3,0,0,0,0,3,4,3
db 3,0,0,0,0,4,4,4
db 3,0,0,0,0,5,4,5
db 3,0,0,0,0,6,4,6
db 3,0,0,0,0,7,4,7
db 3,0,0,0,0,8,4,8
db 3,0,0,0,0,9,4,9
db 3,0,0,0,0,10,4,10
db 3,0,0,0,0,11,4,11
db 3,0,0,0,0,12,4,12
db 3,0,0,0,0,13,4,13
db 3,0,0,0,0,14,4,14
db 3,0,0,0,0,15,4,15
#else
# error Sorry, rombios only has configurations for 1, 2, or 4 processors.
#endif // if (BX_SMP_PROCESSORS==...)
mp_config_end: // this label used to find length of mp structure
db 0
#if (BX_SMP_PROCESSORS>1)
.align 16
mp_floating_pointer_structure:
db 0x5f, 0x4d, 0x50, 0x5f ; "_MP_" signature
dw mp_config_table, 0xf ;; pointer to MP configuration table
db 1 ;; length of this struct in 16-bit byte chunks
db 4 ;; MP spec revision
db 0xc1 ;; checksum
db 0 ;; MP feature byte 1. value 0 means look at the config table
db 0,0,0,0 ;; MP feature bytes 2-5.
#endif
#endasm
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