wok annotate linux/stuff/linux-header.u @ rev 15203

linux: update boot sector
author Pascal Bellard <pascal.bellard@slitaz.org>
date Sun Sep 08 22:26:29 2013 +0000 (2013-09-08)
parents 48a3c0a87ff7
children 4e70419518ab
rev   line source
pascal@12556 1 --- linux-3.2.14/arch/x86/boot/header.S
pascal@12556 2 +++ linux-3.2.14/arch/x86/boot/header.S
pascal@15203 3 @@ -7,12 +7,14 @@
slaxemulator@8085 4 * modified by more people than can be counted
slaxemulator@8085 5 *
pascal@12556 6 * Rewritten as a common file by H. Peter Anvin (Apr 2007)
slaxemulator@8085 7 + * Rewritten Pascal Bellard (Nov 2009)
slaxemulator@8085 8 *
slaxemulator@8085 9 * BIG FAT NOTE: We're in real mode using 64k segments. Therefore segment
slaxemulator@8085 10 * addresses must be multiplied by 16 to obtain their respective linear
pascal@15203 11 * addresses. To avoid confusion, linear addresses are written using leading
pascal@15203 12 * hex while segment addresses are written as segment:offset.
pascal@15203 13 *
pascal@15203 14 + * Assume protocol 2.00+ (kernel >= 1.3.73)
pascal@15203 15 */
pascal@15203 16
pascal@15203 17 #include <asm/segment.h>
pascal@15203 18 @@ -27,6 +29,8 @@
slaxemulator@8085 19
slaxemulator@8085 20 BOOTSEG = 0x07C0 /* original address of boot-sector */
slaxemulator@8085 21 SYSSEG = 0x1000 /* historical load address >> 4 */
slaxemulator@8085 22 +INITSEG = 0x9000 /* boot address >> 4 */
slaxemulator@8085 23 +SETUPSEG = 0x9020 /* setup address >> 4 */
slaxemulator@8085 24
slaxemulator@8085 25 #ifndef SVGA_MODE
slaxemulator@8085 26 #define SVGA_MODE ASK_VGA
pascal@15203 27 @@ -40,53 +44,476 @@
pascal@15203 28 #define ROOT_RDONLY 1
slaxemulator@8085 29 #endif
pascal@15203 30
pascal@15203 31 +setup_sects = 497
pascal@15203 32 +syssize = 500
pascal@15203 33 +cmd_line_ptr = 0x228
pascal@15203 34 +
pascal@15203 35 +/* some extra features */
pascal@15203 36 +#define EXE_SUPPORT real mode dos .exe file support (no himem.sys)
pascal@15203 37 +#define CMDLINE kernel >= 2.4
pascal@15203 38 +#define OLDCMDLINE kernel < 2.4
pascal@15203 39 +#define HELP display version for ? argument
pascal@15203 40 +#define MORETHAN16M up to 4Gb RAM, not 16Mb
pascal@15203 41 +#define KEYBOARDLESS_SUPPORT scan floppy swap each 5 seconds
pascal@15203 42 +#define FULL_ZIMAGE Up to 512K system zImage
pascal@15203 43 +
pascal@15203 44 +/* some limitations to reduce code size */
pascal@15203 45 +//#define FLOPPY_1440K_ONLY 1.44M floppies support only
pascal@15203 46 +
pascal@15203 47 .code16
pascal@15203 48 .section ".bstext", "ax"
slaxemulator@8085 49
slaxemulator@8085 50 .global bootsect_start
slaxemulator@8085 51 bootsect_start:
pascal@15203 52
pascal@15203 53 - # Normalize the start address
pascal@15203 54 - ljmp $BOOTSEG, $start2
pascal@15203 55 +#ifdef EXE_SUPPORT
pascal@15203 56 +#define CODESZ 0x8000
pascal@15203 57 +#define EXEADRS(x) x+0xE0
pascal@15203 58 +stacktop = 0x9E00 # in 0x8000 .. 0xA000
pascal@15203 59 + decw %bp // Magic number: MZ
pascal@15203 60 + popw %dx
pascal@15203 61 + jmp start // Bytes on last page of file
pascal@15203 62 + .word (CODESZ+511)/512 // Pages in file
pascal@15203 63 + .word 0 // Relocations
pascal@15203 64 + .word 2 // Size of header in paragraphs
pascal@15203 65 + .word 4096 // Minimum extra paragraphs needed
pascal@15203 66 + .word -1 // Maximum extra paragraphs needed
pascal@15203 67 + .word (CODESZ+15)/16 // Initial (relative) SS value
pascal@15203 68 + .word stacktop // Initial SP value
pascal@15203 69 + .word 0 // Checksum
pascal@15203 70 + .word EXEADRS(comstart) // Initial IP value
pascal@15203 71 + .word 0xFFF0 // Initial (relative) CS value
pascal@15203 72 +// .word 0x001C // File address of relocation table
pascal@15203 73 +// .word 0,0,0 // Overlay number
pascal@15203 74 +swap_floppy:
pascal@15203 75 + .ascii "Next!"
pascal@15203 76 + .byte 7,13,0 # swap detection needs 13, 0
pascal@15203 77 +#ifdef OLDCMDLINE
pascal@15203 78 + .word 0xA33F
pascal@15203 79 + .word stacktop
pascal@15203 80 +#endif
pascal@15203 81 +start:
pascal@15203 82 + pushw %dx
pascal@15203 83 +#endif
pascal@15203 84
pascal@15203 85 -start2:
pascal@15203 86 - movw %cs, %ax
pascal@15203 87 - movw %ax, %ds
pascal@15203 88 - movw %ax, %es
pascal@15203 89 - movw %ax, %ss
pascal@15203 90 - xorw %sp, %sp
pascal@15203 91 - sti
pascal@15203 92 - cld
pascal@15203 93 +#ifdef FULL_ZIMAGE
pascal@15203 94 +#define LOADSEG 0x8800 // Up to 512K zImage
pascal@15203 95 +#else
pascal@15203 96 +#define LOADSEG 0x8000 // 0x1000 multiple, up to 480K zImage
pascal@15203 97 +#endif
pascal@15203 98 +#define LOADSZ 0x8000
pascal@15203 99
pascal@15203 100 - movw $bugger_off_msg, %si
pascal@15203 101 +bootsect_start:
slaxemulator@8085 102 + cld # assume nothing
slaxemulator@8085 103 +stacktop = 0x9E00 # in 0x8000 .. 0xA000
pascal@12556 104 +zeroed = 48+12 # gdt + zeroed registers
slaxemulator@8085 105 + movw $stacktop-12-zeroed, %di # stacktop is an arbitrary value >=
slaxemulator@8085 106 + # length of bootsect + length of
slaxemulator@8085 107 + # setup + room for stack;
slaxemulator@8085 108 + # 12 is disk parm size.
slaxemulator@8085 109 + pushw $INITSEG
pascal@12556 110 + popw %ss # %ss contain INITSEG
slaxemulator@8085 111 + movw %di, %sp # put stack at INITSEG:stacktop-...
pascal@15203 112 +
slaxemulator@8085 113 +# Many BIOS's default disk parameter tables will not recognize
slaxemulator@8085 114 +# multi-sector reads beyond the maximum sector number specified
slaxemulator@8085 115 +# in the default diskette parameter tables - this may mean 7
slaxemulator@8085 116 +# sectors in some cases.
slaxemulator@8085 117 +#
slaxemulator@8085 118 +# Since single sector reads are slow and out of the question,
slaxemulator@8085 119 +# we must take care of this by creating new parameter tables
slaxemulator@8085 120 +# (for the first disk) in RAM. We can set the maximum sector
slaxemulator@8085 121 +# count to 36 - the most we will encounter on an ED 2.88.
slaxemulator@8085 122 +#
slaxemulator@8085 123 +# High doesn't hurt. Low does. Let's use the max: 63
pascal@15203 124 +
pascal@12556 125 + pushw %ss
pascal@12556 126 + popw %es # %es = %ss = INITSEG
slaxemulator@8085 127 + xorw %ax, %ax # %ax = 0
pascal@15203 128 +#ifdef EXE_SUPPORT
pascal@15203 129 + cwd # floppy = head = 0
pascal@15203 130 +#endif
slaxemulator@8085 131 + movw $zeroed/2, %cx # clear gdt + offset, %ds, limits
slaxemulator@8085 132 + rep # don't worry about cld
slaxemulator@8085 133 + stosw # already done above
slaxemulator@8085 134 + popw %bx # offset = 0
slaxemulator@8085 135 + popw %ds # %ds = 0
pascal@12556 136 + popw %fs # %fs = 0
pascal@15203 137 +
slaxemulator@8085 138 + movb setup_sects+0x7C00, %al # read bootsector + setup (%ds = 0)
slaxemulator@8085 139 + incw %ax
pascal@15203 140 +
pascal@12556 141 + ldsw 0x78(%bx), %si # %ds:%bx+0x78 is parameter table address
slaxemulator@8085 142 + pushw %es
pascal@12556 143 + pushw %di
slaxemulator@8085 144 + movb $6, %cl # copy 12 bytes
slaxemulator@8085 145 + rep # don't worry about cld
slaxemulator@8085 146 + movsw # already done above
pascal@12556 147 + pushw %ss
slaxemulator@8085 148 + popw %ds # now %ds = %es = %ss = INITSEG
pascal@12556 149 + popl %fs:0x78(%bx) # update parameter table address
slaxemulator@8085 150 + movb $63, 0x4-12(%di) # patch sector count, %di = stacktop
slaxemulator@8085 151 + cli
slaxemulator@8085 152 +
slaxemulator@8085 153 + xchg %ax, %di # sector count
slaxemulator@8085 154 + popw %ax # limits = 0
pascal@12556 155 + incw %cx # cylinder 0, sector 1, clear Z
slaxemulator@8085 156 + call read_first_sectors # read setup
pascal@15203 157 +loadsys:
slaxemulator@8085 158 + movw $0x200,%si
pascal@12556 159 +type_of_loader = 0x10
pascal@12556 160 +loadflags = 0x11
pascal@12556 161 +heap_end_ptr = 0x24
pascal@12556 162 + orw $0x8020, type_of_loader(%si) # loader type = 0x20 = bootsect-loader
pascal@12556 163 + movb $(stacktop-0x300)/256, heap_end_ptr+1(%si)
pascal@15203 164 + call puts_version # show which kernel we are loading
slaxemulator@8085 165 +
pascal@12556 166 +# This routine loads the system at address LOADSEG, making sure
slaxemulator@8085 167 +# no 64kB boundaries are crossed. We try to load it as fast as
slaxemulator@8085 168 +# possible, loading whole tracks whenever we can.
pascal@15203 169 +
slaxemulator@8085 170 +ramdisk_image = 0x0218
slaxemulator@8085 171 +ramdisk_size = 0x021C
pascal@12556 172 +bootsect_src_limit = 16
pascal@12556 173 +bootsect_dst_limit = 24
pascal@12556 174 +bootsect_src_base = 18
pascal@15203 175 +bootsect_dst_base = 26 # bits 0..23
pascal@15203 176 +bootsect_dst_base_hi = 31 # bits 24..31
pascal@12556 177 + popw %bx # clear %bx
slaxemulator@8085 178 + movw %sp, %si # for bootsect_gdt
pascal@12556 179 +init_gdt:
pascal@12556 180 + decw bootsect_src_limit(%bx,%si) # max 64Kb
pascal@15203 181 +#if LOADSEG % 0x1000 == 0
pascal@15203 182 + movw $0x9300+(LOADSEG/0x1000), bootsect_src_base+2(%bx,%si)
pascal@15203 183 +#else
pascal@15203 184 + movl $0x93000000+(LOADSEG*0x10), bootsect_src_base(%bx,%si)
pascal@15203 185 +#endif
pascal@12556 186 + xorb $bootsect_dst_limit-bootsect_src_limit, %bl
pascal@12556 187 + jne init_gdt
pascal@12556 188 +code32_start = 0x214
pascal@15203 189 +#ifdef MORETHAN16M
pascal@15203 190 + movb code32_start+3, %al # destination = 0x00100000 or 0x00010000
pascal@15203 191 + movb %al, bootsect_dst_base_hi(%si) # load high (> 16M) ?
pascal@15203 192 +#endif
pascal@12556 193 + movw code32_start+1, %ax # destination = 0x00100000 or 0x00010000
pascal@15203 194 + movl syssize, %ebx
pascal@12556 195 + decl %ebx
pascal@15203 196 + shrl $5, %ebx
pascal@15203 197 + incl %ebx
slaxemulator@8085 198 +syslp:
pascal@12556 199 + movw %ax, bootsect_dst_base+1(%si)
pascal@15203 200 + movw $LOADSZ/512, %di # size in sectors
pascal@15203 201 + subl $LOADSZ/512, %ebx
slaxemulator@8085 202 + pushf
slaxemulator@8085 203 + jnc not_last
pascal@12556 204 + addw %bx, %di
slaxemulator@8085 205 +not_last:
slaxemulator@8085 206 + pushw %ax
slaxemulator@8085 207 + pushw %si
pascal@12556 208 + pushw %bx
pascal@12556 209 + xorw %bx,%bx
pascal@15203 210 + pushw $LOADSEG
pascal@15203 211 + popw %es
pascal@15203 212 +patchcall:
pascal@12556 213 + call read_sectors # update %bp
pascal@12556 214 + popw %bx
slaxemulator@8085 215 + popw %si
pascal@15203 216 + movw $LOADSZ/2, %cx # word count
slaxemulator@8085 217 + movb $0x87, %ah
pascal@12556 218 + pushw %ss
pascal@12556 219 + popw %es # restore es
pascal@15203 220 + int $0x15 # max 16M, maybe more...
slaxemulator@8085 221 + popw %ax
pascal@15203 222 + addw $LOADSZ/256, %ax # next dest
pascal@15203 223 +#ifdef MORETHAN16M
pascal@15203 224 + adcb %cl, bootsect_dst_base_hi(%si) # breaks 16M limit ?
pascal@15203 225 +#endif
slaxemulator@8085 226 + popf
slaxemulator@8085 227 + ja syslp
pascal@12556 228
pascal@15203 229 -msg_loop:
pascal@15203 230 - lodsb
pascal@15203 231 - andb %al, %al
pascal@15203 232 - jz bs_die
pascal@15203 233 - movb $0xe, %ah
pascal@15203 234 - movw $7, %bx
pascal@15203 235 - int $0x10
pascal@15203 236 - jmp msg_loop
pascal@15203 237 -
pascal@15203 238 -bs_die:
pascal@15203 239 - # Allow the user to press a key, then reboot
pascal@15203 240 - xorw %ax, %ax
slaxemulator@8085 241 +# This procedure turns off the floppy drive motor, so
slaxemulator@8085 242 +# that we enter the kernel in a known state, and
slaxemulator@8085 243 +# don't have to worry about it later.
pascal@15203 244 +
pascal@12556 245 +kill_motor:
pascal@12556 246 + xchgw %ax, %di # reset FDC (%di < 128)
pascal@12556 247 + int $0x13
slaxemulator@8085 248 +
slaxemulator@8085 249 +# After that (everything loaded), we jump to the setup-routine
slaxemulator@8085 250 +# loaded directly after the bootblock:
slaxemulator@8085 251 +# Segments are as follows: %ds = %ss = INITSEG
slaxemulator@8085 252 +
slaxemulator@8085 253 + ljmp $SETUPSEG, $0
slaxemulator@8085 254 +
slaxemulator@8085 255 +# read_sectors reads %di sectors into %es:0 buffer.
slaxemulator@8085 256 +# %es:0 is updated to the next memory location.
slaxemulator@8085 257 +# First, sectors are read sector by sector until
slaxemulator@8085 258 +# sector per track count is known. Then they are
slaxemulator@8085 259 +# read track by track.
slaxemulator@8085 260 +# Assume no error on first track.
slaxemulator@8085 261 +
slaxemulator@8085 262 +#define FLOPPY_CYLINDERS 80 /* 80 cylinders minimum */
slaxemulator@8085 263 +#define FLOPPY_HEADS 2 /* 2 heads minimum */
slaxemulator@8085 264 +#define FLOPPY_SECTORS 18 /* 18 sectors minimum */
slaxemulator@8085 265 +
slaxemulator@8085 266 +check_limits:
pascal@15203 267 +#ifndef FLOPPY_1440K_ONLY
pascal@15203 268 + popw %dx
slaxemulator@8085 269 + cmpb $FLOPPY_SECTORS+1, %cl # 18 sectors minimum
slaxemulator@8085 270 + jb check_head
slaxemulator@8085 271 + cmpb %al, %cl # max sector known ?
slaxemulator@8085 272 + ja next_head # no -> store it
slaxemulator@8085 273 +check_head:
slaxemulator@8085 274 + cmpb $FLOPPY_HEADS, %dh # 2 heads minimum
slaxemulator@8085 275 + jb check_cylinder
slaxemulator@8085 276 + cmpb %ah, %dh # max head known ?
slaxemulator@8085 277 + ja next_cylinder # no -> store it
slaxemulator@8085 278 +check_cylinder:
pascal@15203 279 +#endif
slaxemulator@8085 280 + pushaw
pascal@15203 281 +#ifndef FLOPPY_1440K_ONLY
slaxemulator@8085 282 + cbw # %ah = 0
pascal@15203 283 +#endif
slaxemulator@8085 284 + int $0x13 # reset controler
pascal@15203 285 + stc
pascal@15203 286 + call putcdot # print '-'
pascal@15203 287 +read_sectorslp:
slaxemulator@8085 288 + popaw
pascal@15203 289 +bdendlp:
slaxemulator@8085 290 + pushw %dx # some bios break dx...
pascal@15203 291 +#ifndef FLOPPY_1440K_ONLY
slaxemulator@8085 292 + pushw %ax # limits
slaxemulator@8085 293 + subb %cl, %al # sectors remaining in track
slaxemulator@8085 294 + ja tolastsect
slaxemulator@8085 295 + movb $1, %al # 1 sector mini
slaxemulator@8085 296 +tolastsect:
pascal@15203 297 +#else
pascal@15203 298 + mov $FLOPPY_SECTORS+1, %al
pascal@15203 299 + subb %cl, %al # sectors remaining in track
pascal@15203 300 +#endif
slaxemulator@8085 301 + cbw
slaxemulator@8085 302 + cmpw %di, %ax
slaxemulator@8085 303 + jb more1trk
slaxemulator@8085 304 + movw %di, %ax # sectors to read
slaxemulator@8085 305 +more1trk:
slaxemulator@8085 306 + pushw %ax # save context
slaxemulator@8085 307 + movb $2, %ah # cmd: read chs
slaxemulator@8085 308 + int $0x13
pascal@15203 309 +#ifndef FLOPPY_1440K_ONLY
pascal@15203 310 + popw %dx # save %ax
slaxemulator@8085 311 + popw %ax # limits
pascal@15203 312 +#else
pascal@15203 313 + popw %ax # restore context
slaxemulator@8085 314 + popw %dx
pascal@15203 315 +#endif
slaxemulator@8085 316 + jc check_limits
pascal@15203 317 +#ifndef FLOPPY_1440K_ONLY
slaxemulator@8085 318 + xchgw %ax, %bp
pascal@15203 319 + addw %dx,%cx # next sector
pascal@12556 320 + movw %cx, %gs
pascal@15203 321 + addb %dl,%bh
pascal@15203 322 + addb %dl,%bh # next location
pascal@15203 323 + subw %dx,%di # update sector counter
pascal@15203 324 + popw %dx
slaxemulator@8085 325 + jz putcdot
pascal@15203 326 +#else
pascal@15203 327 + addw %ax,%cx # next sector
pascal@15203 328 + movw %cx, %gs
pascal@15203 329 + addb %al,%bh
pascal@15203 330 + addb %al,%bh # next location
pascal@15203 331 + subw %ax,%di # update sector counter
pascal@15203 332 + jz putcdot
pascal@15203 333 +#endif
slaxemulator@8085 334 +read_sectors:
pascal@12556 335 + movw %gs, %cx
pascal@15203 336 +#ifndef FLOPPY_1440K_ONLY
pascal@12556 337 +# al is last sector+1
pascal@12556 338 +# ah is last cylinder+1
slaxemulator@8085 339 + xchgw %ax, %bp
pascal@15203 340 +#endif
pascal@15203 341 +#ifndef FLOPPY_1440K_ONLY
slaxemulator@8085 342 + cmpb %al,%cl # reach sector limit ?
slaxemulator@8085 343 + jne bdendlp
slaxemulator@8085 344 +next_head:
slaxemulator@8085 345 + movb %cl,%al
pascal@15203 346 +#else
pascal@15203 347 + cmpb $FLOPPY_SECTORS+1,%cl # reach sector limit ?
pascal@15203 348 + jne bdendlp
pascal@15203 349 +#endif
slaxemulator@8085 350 + incb %dh # next head
slaxemulator@8085 351 + movb $1,%cl # first sector
pascal@15203 352 +#ifndef FLOPPY_1440K_ONLY
slaxemulator@8085 353 + cmpb %ah, %dh # reach head limit ?
slaxemulator@8085 354 + jne bdendlp
slaxemulator@8085 355 +next_cylinder:
slaxemulator@8085 356 + movb %dh,%ah
pascal@15203 357 +#else
pascal@15203 358 + cmpb %cl,%dh # reach head limit ?
pascal@15203 359 + je bdendlp
pascal@15203 360 +#endif
slaxemulator@8085 361 +# NOTE : support 256 cylinders max
slaxemulator@8085 362 + incb %ch # next cylinder
slaxemulator@8085 363 +read_first_sectors:
pascal@15203 364 + cmpb $FLOPPY_CYLINDERS,%ch # reach cylinder limit ?
slaxemulator@8085 365 + movb $0,%dh # first head
pascal@12556 366 + jne bdendlp
slaxemulator@8085 367 +next_floppy:
slaxemulator@8085 368 + movb $0,%ch # first cylinder
slaxemulator@8085 369 + pushaw
slaxemulator@8085 370 + movw $swap_floppy,%si
pascal@15203 371 +#ifdef KEYBOARDLESS_SUPPORT
slaxemulator@8085 372 + pushw %bx
pascal@12556 373 + call puts
slaxemulator@8085 374 + popw %bx
slaxemulator@8085 375 +waitfloppy:
slaxemulator@8085 376 + call wait
slaxemulator@8085 377 + jne waitfloppydone
slaxemulator@8085 378 + pushw %dx # some bios break dx...
slaxemulator@8085 379 + cbw
slaxemulator@8085 380 + int $0x13 # reset FDC
slaxemulator@8085 381 + movw $0x201,%ax
slaxemulator@8085 382 + int $0x13 # read first sector
slaxemulator@8085 383 + popw %dx
slaxemulator@8085 384 + rclb $1,%ah # floppy changed 06=>0D no error 00
slaxemulator@8085 385 + cmpb -2(%si), %ah # 0D then 00
slaxemulator@8085 386 + jne waitfloppy # no => try again
slaxemulator@8085 387 + incw %si
pascal@15203 388 + decw %ax # was 0001 ?
slaxemulator@8085 389 + jne waitfloppy
slaxemulator@8085 390 +waitfloppydone:
pascal@15203 391 +#else
pascal@15203 392 + call puts
pascal@15203 393 + cbw # %ah = 0, get keyboard character
pascal@15203 394 int $0x16
pascal@15203 395 - int $0x19
pascal@15203 396 +#endif
slaxemulator@8085 397 + jmp read_sectorslp
slaxemulator@8085 398 +
pascal@15203 399 +#ifdef EXE_SUPPORT
pascal@15203 400 +read_sectors_dos:
pascal@15203 401 + pushw %es
pascal@15203 402 + popw %ds
pascal@15203 403 + movb $0x3F, %ah // read
pascal@15203 404 + cwd // write to %ds:%dx, not %es:%bx
pascal@15203 405 + movw %di, %cx
pascal@15203 406 + shlw $9, %cx // byte count
pascal@15203 407 + movw %bp, %bx
pascal@15203 408 + int $0x21
pascal@15203 409 + pushw %ss
pascal@15203 410 + popw %ds
pascal@15203 411 +#endif
pascal@15203 412
pascal@15203 413 - # int 0x19 should never return. In case it does anyway,
pascal@15203 414 - # invoke the BIOS reset code...
pascal@15203 415 - ljmp $0xf000,$0xfff0
pascal@15203 416 -
pascal@15203 417 - .section ".bsdata", "a"
pascal@15203 418 -bugger_off_msg:
pascal@15203 419 - .ascii "Direct booting from floppy is no longer supported.\r\n"
pascal@15203 420 - .ascii "Please use a boot loader program instead.\r\n"
pascal@15203 421 - .ascii "\n"
pascal@15203 422 - .ascii "Remove disk and press any key to reboot . . .\r\n"
pascal@15203 423 - .byte 0
slaxemulator@8085 424 +putcdot:
pascal@15203 425 + movb $'.'+3, %al // . = success, - = failure
slaxemulator@8085 426 +putclf:
pascal@15203 427 + sbbb $3, %al
slaxemulator@8085 428 +putc:
slaxemulator@8085 429 + movb $0xe, %ah
slaxemulator@8085 430 + movw $7, %bx # one dot each 64k
slaxemulator@8085 431 + int $0x10
slaxemulator@8085 432 + cmp $0xd, %al # CR ?
slaxemulator@8085 433 + je putclf
slaxemulator@8085 434 + ret
slaxemulator@8085 435 +
pascal@15203 436 +#ifdef KEYBOARDLESS_SUPPORT
slaxemulator@8085 437 +clock = 0x46C
slaxemulator@8085 438 +wait:
slaxemulator@8085 439 +wait4key:
slaxemulator@8085 440 + movw $clock, %di
slaxemulator@8085 441 +#define DELAY 5
pascal@15203 442 + movb $257-(DELAY*182)/10, %fs:(%di)
slaxemulator@8085 443 +waitkbd:
slaxemulator@8085 444 + movw $0x10D, %ax # test keyboard, timeout => CR
pascal@15203 445 + cmpb %fs:(%di),%ah
slaxemulator@8085 446 + je waitdone
pascal@12556 447 + int $0x16
slaxemulator@8085 448 + jz waitkbd
slaxemulator@8085 449 + cbw
slaxemulator@8085 450 + int $0x16 # eat char
pascal@12556 451 + movw %di, %fs # disable timeout
slaxemulator@8085 452 + incw %di # clear Z
slaxemulator@8085 453 +waitdone:
slaxemulator@8085 454 + ret
pascal@15203 455 +#endif
pascal@15203 456
pascal@15203 457 +#ifdef EXE_SUPPORT
pascal@15203 458 +comstart:
pascal@15203 459 + cld # assume nothing
pascal@15203 460 + pushw $INITSEG
pascal@15203 461 + popw %es
pascal@15203 462 + pushw %es
pascal@15203 463 + popw %ss
pascal@15203 464 +#ifdef CMDLINE
pascal@15203 465 + movw %sp, %di
pascal@15203 466 + movw $0x80, %si
pascal@15203 467 + lodsb
pascal@15203 468 + cbw
pascal@15203 469 + xchgw %ax, %cx
pascal@15203 470 + rep
pascal@15203 471 + movsb
pascal@15203 472 + movb $(48+2)/2, %cl
pascal@15203 473 + xorw %bx, %bx
pascal@15203 474 +clearstacklp:
pascal@15203 475 + pushw %bx
pascal@15203 476 + loop clearstacklp
pascal@15203 477 +# ifdef HELP
pascal@15203 478 + cmpb $'?', -1(%si)
pascal@15203 479 + movw $EXEADRS(0x200), %si
pascal@15203 480 + movw setup_sects-0x200(%si), %di // bits 0..6
pascal@15203 481 + je puts_version
pascal@15203 482 + smsww %ax
pascal@15203 483 + andb $1, %al
pascal@15203 484 + jne puts_version // real mode only...
pascal@15203 485 +# endif
pascal@15203 486 +#else
pascal@15203 487 + movw $(48+2)/2, %cx
pascal@15203 488 + xorw %bx, %bx
pascal@15203 489 +clearstacklp:
pascal@15203 490 + pushw %bx
pascal@15203 491 + loop clearstacklp
pascal@15203 492 +#endif
pascal@15203 493 +#if !defined(CMDLINE) || !defined(HELP)
pascal@15203 494 + movw EXEADRS(setup_sects), %di // bits 0..6
pascal@15203 495 + movb $0, %al // access = RO
pascal@15203 496 +#endif
pascal@15203 497 + movw 0x2C(%bx), %ds // DOS 3.0+
pascal@15203 498 +loop1:
pascal@15203 499 + incw %bx
pascal@15203 500 + cmpw %cx, (%bx)
pascal@15203 501 + jne loop1
pascal@15203 502 + leaw 4(%bx), %dx // %ds:%dx filename
pascal@15203 503 + movb $0x3D, %ah // open, access = RO
pascal@15203 504 + int $0x21
pascal@15203 505 + jc dosexit
pascal@15203 506 + xchgw %ax, %bp // fd
pascal@15203 507 + incw %di
pascal@15203 508 + call read_sectors_dos // update %ds
pascal@15203 509 + addb $read_sectors_dos-read_sectors, patchcall+1
pascal@15203 510 +#ifdef CMDLINE
pascal@15203 511 +# ifdef OLDCMDLINE
pascal@15203 512 + movw $0x202, %bx
pascal@15203 513 + cmpw %bx, 0x206-0x202(%bx)
pascal@15203 514 + jb oldcmdline
pascal@15203 515 + movw $INITSEG/16+stacktop/256, cmd_line_ptr+1-0x202(%bx)
pascal@15203 516 +oldcmdline:
pascal@15203 517 +# else
pascal@15203 518 + movw $INITSEG/16+stacktop/256, cmd_line_ptr+1
pascal@15203 519 +# endif
pascal@15203 520 +#endif
pascal@15203 521 + ljmp $INITSEG, $loadsys
pascal@15203 522 +#endif
pascal@15203 523 +
pascal@15203 524 +#define kernel_version 0xE
pascal@15203 525 +puts_version:
pascal@15203 526 + addw kernel_version(%si),%si # starting protocol 2.00, Kernel 1.3.73
pascal@15203 527 +puts:
pascal@15203 528 + movb $0xd, %al # CR
pascal@15203 529 +putcs:
pascal@15203 530 + call putc
pascal@15203 531 + lodsb
pascal@15203 532 + cmpb $0, %al # end of string is any byte <= 0
pascal@15203 533 + jg putcs
pascal@15203 534 +dosexit:
pascal@15203 535 + ret
slaxemulator@8085 536
slaxemulator@8085 537 # Kernel attributes; used by setup. This is part 1 of the
slaxemulator@8085 538 # header, from the old boot sector.