wok-6.x annotate runcom/stuff/debug8086.S @ rev 20666

cookutils: patch to make correct packages database.
All packages.* and SliTaz Cooking on the Repology are affected.
author Aleksej Bobylev <al.bobylev@gmail.com>
date Sat Jan 19 13:41:36 2019 +0200 (2019-01-19)
parents 289a2f495cd6
children
rev   line source
pascal@11674 1 // Usage:
pascal@11674 2 //
pascal@11674 3 // f DX:CX load one CHS sector to 0000:7C00
pascal@11674 4 // t trace one step
pascal@11674 5 // g <address> go to adrs
pascal@11674 6 // d <address> display 16 bytes, CR for next 16 bytes...
pascal@11674 7 // e <address> <words>... enter memory byte/word/dword
pascal@11674 8 // m <segment> self move
pascal@11674 9 // + <segment> default segment offset
pascal@11674 10 //
pascal@11674 11 // Example:
pascal@11674 12 // m 0FC0 move debugger to 0FC0:0000 0FC0:01FF
pascal@11674 13 // f 1 read floppy boot sector to 0000:7C00
pascal@13055 14 // f 80:1 read hard disk master boot sector to 0000:7C00
pascal@11674 15 // g 7C0E ...
pascal@11674 16
pascal@11674 17 #define ADJESDI 16 bytes add segment overflow support for e and d
pascal@11674 18 #define ASCIIDUMP 20 bytes display hexa and ascii datas
pascal@11674 19 #define INPUTBUFFER 2 bytes overload init code with a 32+ bytes input buffer
pascal@11674 20 //#define CPU186 -26 bytes 80186+ CPU
pascal@11674 21
pascal@11674 22 .macro pusham
pascal@11674 23 pushw %ax
pascal@11674 24 pushw %cx
pascal@11674 25 pushw %dx
pascal@11674 26 pushw %bx
pascal@11674 27 movw %sp, %bx
pascal@11674 28 leaw 14(%bx), %bx # adjust SP with [FLAGS CS IP AX CX DX BX] size
pascal@11674 29 pushw %bx # %sp
pascal@11674 30 pushw %bp
pascal@11674 31 pushw %si
pascal@11674 32 pushw %di
pascal@11674 33 .endm
pascal@11674 34
pascal@11674 35 .macro popam
pascal@11674 36 popw %di
pascal@11674 37 popw %si
pascal@11674 38 popw %bp
pascal@11674 39 popw %ax # %sp
pascal@11674 40 popw %bx
pascal@11674 41 popw %dx
pascal@11674 42 popw %cx
pascal@11674 43 popw %ax
pascal@11674 44 .endm
pascal@11674 45
pascal@11674 46 #ifdef INPUTBUFFER
pascal@11674 47 //#define ABS(x) (x-(setvectors-_start))
pascal@11674 48 #define ABS(x) (x-30)
pascal@11674 49 #else
pascal@11674 50 #define ABS(x) (x)
pascal@11674 51 #endif
pascal@11674 52
pascal@11674 53 #define SEGREGSZ 6
pascal@11674 54 #define REGSZ 16
pascal@11674 55 #define USER_SP REGSZ+SEGREGSZ-10(%bp)
pascal@11674 56 #define USER_FLAGS REGSZ+SEGREGSZ+4(%bp)
pascal@11674 57 #define USER_FLAGS_HIGH REGSZ+SEGREGSZ+5(%bp)
pascal@11674 58 #define USER_IP REGSZ+SEGREGSZ(%bp)
pascal@11674 59 #define USER_CS REGSZ+SEGREGSZ+2(%bp)
pascal@11674 60 #define USER_CSIP REGSZ+SEGREGSZ(%bp)
pascal@11674 61
pascal@11674 62 .macro initcode
pascal@11674 63 movw $0x0FC0, %di # move (and jump) to 0FC0:0000
pascal@11674 64 subw $_startz-_start, USER_IP
pascal@11674 65 movw USER_IP, %ax
pascal@11674 66 #ifdef CPU186
pascal@11674 67 cld # ensure movsb will work
pascal@11674 68 shrw $4, %ax # _start MUST be aligned on paragraph
pascal@11674 69 #else
pascal@11674 70 movb $4, %cl
pascal@11674 71 shrw %cl, %ax # _start MUST be aligned on paragraph
pascal@11674 72 #endif
pascal@11674 73 addw USER_CS, %ax # normalize %cs to have _start=0
pascal@11674 74 movw %ax, %ds
pascal@11674 75 .endm
pascal@11674 76 .text
pascal@11674 77 .code16
pascal@11674 78 #ifdef CPU186
pascal@11674 79 .arch i186
pascal@11674 80 #else
pascal@11674 81 .arch i8086
pascal@11674 82 #endif
pascal@11674 83 .org 0
pascal@11674 84
pascal@11674 85 .globl _start
pascal@11674 86 _start:
pascal@11674 87 pushf
pascal@11674 88 pushw %cs
pascal@11674 89 stc
pascal@11674 90 call init # the start code will be overwritten by the input buffer
pascal@11674 91 _startz:
pascal@11674 92
pascal@11674 93 #ifdef INPUTBUFFER
pascal@11674 94 isinit:
pascal@11674 95 initcode
pascal@11674 96 movw $setvectors, %si
pascal@11674 97 jmp moveself
pascal@11674 98 #endif
pascal@11674 99
pascal@11674 100 setvectors:
pascal@11674 101 xorw %si, %si # set interrupt vectors in 0 segment
pascal@11674 102 movw %si, %ds
pascal@11674 103 movb $0xF9, %ch # skip nmi
pascal@11674 104 hooklp: # interrupts: 0=div0 1=step 2=nmi 3=brk 4=ov 5=bound 6=invalid
pascal@11674 105 movw $ABS(dbgstart), (%si) # set %cs:dbgstart
pascal@11674 106 lodsw # %si += 2
pascal@11674 107 movw %cs, (%si) # to interrupt vector
pascal@11674 108 skiphook:
pascal@11674 109 lodsw # %si += 2
pascal@11674 110 shrb $1,%ch
pascal@11674 111 jnc skiphook
pascal@11674 112 jnz hooklp # note %cx will be cleared: SP will be untouched
pascal@11674 113 #ifdef CPU186
pascal@11674 114 decw (3-7)*4(%si) # update int3 vector
pascal@11674 115 #else
pascal@11674 116 movb $ABS(int3), (3-7)*4(%si) # update int3 vector
pascal@11674 117 #endif
pascal@11674 118 jmp dbgstartz # registers are already pushed by startup code
pascal@11674 119
pascal@11674 120 regs:
pascal@11674 121 .ascii "ss"
pascal@11674 122 .ascii "es"
pascal@11674 123 .ascii "ds"
pascal@11674 124 .ascii "di"
pascal@11674 125 .ascii "si"
pascal@11674 126 .ascii "bp"
pascal@11674 127 .ascii "sp"
pascal@11674 128 .ascii "bx"
pascal@11674 129 .ascii "dx"
pascal@11674 130 .ascii "cx"
pascal@11674 131 .ascii "ax"
pascal@11674 132 .ascii "ip"
pascal@11674 133 .ascii "cs"
pascal@11674 134 # Bit Label Desciption
pascal@11674 135 # ---------------------------
pascal@11674 136 # 0 CF Carry flag
pascal@11674 137 # 2 PF Parity flag
pascal@11674 138 # 4 AF Auxiliary carry flag
pascal@11674 139 # 6 ZF Zero flag
pascal@11674 140 # 7 SF Sign flag
pascal@11674 141 # 8 TF Trap flag
pascal@11674 142 # 9 IF Interrupt enable flag
pascal@11674 143 # 10 DF Direction flag
pascal@11674 144 # 11 OF Overflow flag
pascal@11674 145 .ascii "oditsz?a?p c=" # flags bits
pascal@11674 146
pascal@11674 147 int3:
pascal@11674 148 #ifdef CPU186
pascal@11674 149 .byte 0x68 # push $0x086A OV UP DI NT PL ZR - NA - PO - NC
pascal@11674 150 # interrupt entry point: the registers [FLAGS CS IP] are already pushed
pascal@11674 151 dbgstart:
pascal@11674 152 .byte 0x6A, 0x08 # push $0x08 NV UP DI NT PL NZ - NA - PO - NC
pascal@11674 153 popf
pascal@11674 154 init:
pascal@11674 155 pushaw # [FLAGS CS IP] AX CX DX BX SP BP SI DI [DS ES SS]
pascal@11674 156 #else
pascal@11674 157 stc
pascal@11674 158 .byte 0x73 # jnc
pascal@11674 159 # interrupt entry point: the registers [FLAGS CS IP] are already pushed
pascal@11674 160 dbgstart:
pascal@11674 161 clc
pascal@11674 162 pushw %ax
pascal@11674 163 sbbw %ax,%ax # copy CF to SF
pascal@11674 164 clc
pascal@11674 165 popw %ax
pascal@11674 166 init:
pascal@11674 167 cld # ensure movsb will work
pascal@11674 168 pusham # [FLAGS CS IP] AX CX DX BX SP BP SI DI [DS ES SS]
pascal@11674 169 #endif
pascal@11674 170 pushw %ds
pascal@11674 171 pushw %es
pascal@11674 172 pushw %ss
pascal@11674 173 movw %sp, %bp
pascal@11674 174 #ifdef CPU186
pascal@11674 175 pushf
pascal@11674 176 addw $6, USER_SP # adjust SP with [FLAGS CS IP] size
pascal@11674 177 popf
pascal@11674 178 #endif
pascal@11674 179 jc isinit
pascal@11674 180 jns notint3
pascal@11674 181 decw USER_IP
pascal@11674 182 lesw USER_CSIP, %di
pascal@11674 183 #define OPCODE_BRK 0xCC
pascal@11674 184 .byte 0xB0 # movb $IM, %al
pascal@11674 185 break:
pascal@11674 186 .byte 0xCC
pascal@11674 187 stosb
pascal@11674 188 notint3:
pascal@11674 189 dbgstartz:
pascal@11674 190 dbgregslp:
pascal@11674 191 call getcmd
pascal@11674 192 .byte 0x81, 0xC3 # addw $0, %bx
pascal@11674 193 offset_value:
pascal@11674 194 .word 0
pascal@11674 195 movw %bx, %es
pascal@11674 196 xchgw %ax, %di
pascal@11674 197 subb $'m', %al
pascal@11674 198 jne isinotmove
pascal@11674 199 #ifdef INPUTBUFFER
pascal@11674 200 ismove:
pascal@11674 201 xchgw %ax, %si
pascal@11674 202 moveself:
pascal@11674 203 #else
pascal@11674 204 isinit:
pascal@11674 205 jmp ismove
pascal@11674 206 initcode
pascal@11674 207 ismove:
pascal@11674 208 #endif
pascal@11674 209 movw %di, %es # move code to %di:0
pascal@11674 210 pushw %di
pascal@11674 211 #ifdef INPUTBUFFER
pascal@11674 212 xorw %di, %di # and jmp into (%di:setvectors) with retf
pascal@11674 213 #else
pascal@11674 214 movw $setvectors, %di # and jmp into (%di:setvectors) with retf
pascal@11674 215 movw %di, %si
pascal@11674 216 #endif
pascal@11674 217 movw $_end-setvectors, %cx
pascal@11674 218 pushw %di
pascal@11674 219 rep movsb
pascal@11674 220 retf
pascal@11674 221
pascal@11674 222 isinotmove:
pascal@11674 223 subb $'+'-'m', %al
pascal@11674 224 jne not_offset
pascal@11674 225 movw %di, ABS(offset_value)
pascal@11674 226 not_offset:
pascal@11674 227 orb $1, USER_FLAGS_HIGH # set TF
pascal@11674 228 subb $'t'-'+', %al
pascal@11674 229 je done
pascal@11674 230 subb $'d'-'t', %al
pascal@11674 231 xchgw %ax, %cx
pascal@11674 232 jcxz dump # 'd' ?
pascal@11674 233 loop noenter # 'e' ?
pascal@11674 234 nextval:
pascal@11674 235 call getval
pascal@11674 236 jcxz dbgregslp
pascal@11674 237 xchgb %dl, %dh
pascal@11674 238 mextmsb:
pascal@11674 239 stosb
pascal@11674 240 xchgw %ax, %dx
pascal@11674 241 xchgb %al, %dh
pascal@11674 242 #ifdef ADJESDI
pascal@11674 243 call adjustESDI
pascal@11674 244 #endif
pascal@11674 245 decw %cx
pascal@11674 246 loopne mextmsb
pascal@11674 247 jmp nextval
pascal@11674 248 noenter:
pascal@11674 249 loop not_floppy_load # f DX:CX ?
pascal@11674 250 movw %es, %dx
pascal@11674 251 movw %cx, %es
pascal@11674 252 movw %di, %cx
pascal@11674 253 movw $0x0201, %ax
pascal@11674 254 movw $0x7C00, %bx
pascal@11674 255 pushw %bx
pascal@11674 256 int $0x13
pascal@11674 257 popw %di
pascal@11674 258 godbgregslpifc:
pascal@11674 259 jc dbgregslp
pascal@11674 260 dump:
pascal@11674 261 movw %es, %ax
pascal@11674 262 call putax
pascal@11674 263 movw %di, %ax
pascal@11674 264 call putax
pascal@11674 265 movw $16, %cx
pascal@11674 266 dhex:
pascal@11674 267 movb %es:(%di), %ah
pascal@11674 268 #ifdef ASCIIDUMP
pascal@11674 269 movb %ah, (%si)
pascal@11674 270 incw %si
pascal@11674 271 #endif
pascal@11674 272 #ifdef ADJESDI
pascal@11674 273 call incESDI
pascal@11674 274 #else
pascal@11674 275 incw %di
pascal@11674 276 #endif
pascal@11674 277 movb $0x01, %dh # the data has 2 digits
pascal@11674 278 call putx
pascal@11674 279 loop dhex
pascal@11674 280 #ifdef ASCIIDUMP
pascal@11674 281 movb $16, %cl
pascal@11674 282 subw %cx, %si
pascal@11674 283 dascii:
pascal@11674 284 lodsb
pascal@11674 285 cmpb $0x7F, %al
pascal@11674 286 jnc skipascii
pascal@11674 287 cmpb $0x20, %al
pascal@11674 288 cmc
pascal@11674 289 skipascii:
pascal@11674 290 call dbgputcbit
pascal@11674 291 loop dascii
pascal@11674 292 #endif
pascal@11674 293 call dbgputcr
pascal@11674 294 int $0x16
pascal@11674 295 cmpb $13, %al
pascal@11674 296 je dump
pascal@11674 297 notdump:
pascal@11674 298 not_floppy_load:
pascal@11674 299 stc
pascal@11674 300 loop godbgregslpifc # g ?
pascal@11674 301 isgo:
pascal@11674 302 andb $0xfe, USER_FLAGS_HIGH # clear TF
pascal@11674 303 xchgw %ax, %cx
pascal@11674 304 jcxz done
pascal@11674 305 setbreak:
pascal@11674 306 movb $OPCODE_BRK, %al
pascal@11674 307 xchgb %al, %es:(%di)
pascal@11674 308 movb %al, ABS(break)
pascal@11674 309 done:
pascal@11674 310 popw %ax # %ss
pascal@11674 311 popw %es
pascal@11674 312 popw %ds
pascal@11674 313 #ifdef CPU186
pascal@11674 314 popaw
pascal@11674 315 #else
pascal@11674 316 popam
pascal@11674 317 #endif
pascal@11674 318 iret
pascal@11674 319
pascal@11674 320 #ifdef ADJESDI
pascal@11674 321 adjustESDI:
pascal@11674 322 decw %di
pascal@11674 323 incESDI:
pascal@11674 324 incw %di
pascal@11674 325 jnz esok
pascal@11674 326 pushw %es
pascal@11674 327 addb $0x10,-3(%bp)
pascal@11674 328 popw %es
pascal@11674 329 esok:
pascal@11674 330 ret
pascal@11674 331 #endif
pascal@11674 332
pascal@11674 333 putreg:
pascal@11674 334 call dbgput2c
pascal@11674 335 movb $'=', %al
pascal@11674 336 call dbgputc
pascal@11674 337 putr16:
pascal@11674 338 # movw _start-ABS(regs)-2(%bp,%si), %ax
pascal@11674 339 .byte 0x8b, 0x42, _start-ABS(regs)-2
pascal@11674 340 putax:
pascal@11674 341 movb $0x07, %dh # the data has 4 digits
pascal@11674 342 putx:
pascal@11674 343 putxlp:
pascal@11674 344 #ifdef CPU186
pascal@11674 345 rolw $4, %ax
pascal@11674 346 #else
pascal@11674 347 pushw %cx
pascal@11674 348 movb $4, %cl
pascal@11674 349 rolw %cl, %ax
pascal@11674 350 popw %cx
pascal@11674 351 #endif
pascal@11674 352 pushw %ax
pascal@11674 353 andb $0xf, %al
pascal@11674 354 addb $0x90, %al
pascal@11674 355 daa
pascal@11674 356 adcb $0x40, %al
pascal@11674 357 daa
pascal@11674 358 call dbgputc
pascal@11674 359 popw %ax
pascal@11674 360 shrb $1, %dh
pascal@11674 361 jc putxlp
pascal@11674 362 dbgputcbit:
pascal@11674 363 jc dbgputc
pascal@11674 364 mov $0x20, %al
pascal@11674 365 dbgputc:
pascal@11674 366 movw $7, %bx
pascal@11674 367 mov $0xE, %ah
pascal@11674 368 int $0x10
pascal@11674 369 xchgw %ax, %bx
pascal@11674 370 ret
pascal@11674 371
pascal@11674 372 getline:
pascal@11674 373 movw $ABS(regs), %si
pascal@11674 374 movw $13, %cx
pascal@11674 375 regslp:
pascal@11674 376 call putreg # display register name and value
pascal@11674 377 loop regslp
pascal@11674 378 movw USER_FLAGS, %dx
pascal@11674 379 pushw %si
pascal@11674 380 movb $13, %cl
pascal@11674 381 stc # add trailing =
pascal@11674 382 rcrw %cl, %dx
pascal@11674 383 nextbit:
pascal@11674 384 lodsb
pascal@11674 385 shlw $1, %dx
pascal@11674 386 call dbgputcbit # display active flags bits
pascal@11674 387 loop nextbit
pascal@11674 388 popw %si
pascal@11674 389 movb $8, %cl
pascal@11674 390 stacklp:
pascal@11674 391 lodsw # si += 2
pascal@11674 392 call putr16 # display flags and the beginning of the stack
pascal@11674 393 loop stacklp
pascal@11674 394 call dbgputcr
pascal@11674 395 getlinebs:
pascal@11674 396 cmpw $ABS(buffer), %si
pascal@11674 397 je getc
pascal@11674 398 decw %si
pascal@11674 399 getlinelp:
pascal@11674 400 call dbgputc
pascal@11674 401 getc:
pascal@11674 402 int $0x16
pascal@11674 403 cmpb $8, %al
pascal@11674 404 je getlinebs
pascal@11674 405 orb $0x20, %al
pascal@11674 406 movb %al, (%si)
pascal@11674 407 inc %si
pascal@11674 408 cmpb $0x2D, %al
pascal@11674 409 jne getlinelp
pascal@11674 410 dbgputcr:
pascal@11674 411 movw $ABS(crlf), %si
pascal@11674 412 dbgput2c:
pascal@11674 413 call dbgput1c
pascal@11674 414 dbgput1c:
pascal@11674 415 lodsb
pascal@11674 416 jmp dbgputc
pascal@11674 417
pascal@11674 418 getcmd:
pascal@11674 419 pushw %cs
pascal@11674 420 popw %ds
pascal@11674 421 call getline
pascal@11674 422 lodsb
pascal@11674 423 xchgw %ax, %di
pascal@11674 424 # get value in DX:AX, BX is segment CX is digits count.
pascal@11674 425 getval:
pascal@11674 426 xorw %bx, %bx
pascal@11674 427 xorw %cx, %cx
pascal@11674 428 getvalz:
pascal@11674 429 pushw %bx # save segment
pascal@11674 430 xorw %bx, %bx
pascal@11674 431 mul %bx # clear %dx:%ax
pascal@11674 432 decw %cx
pascal@11674 433 isx:
pascal@11674 434 incw %cx
pascal@11674 435 orb $0xE0, %dh
pascal@11674 436 getvalbit:
pascal@11674 437 shlw $1, %bx
pascal@11674 438 rclw $1, %dx
pascal@11674 439 jc getvalbit
pascal@11674 440 orb %al, %bl
pascal@11674 441 gotspc:
pascal@11674 442 lodsb
pascal@11674 443 cmpb $0x20, %al # space ?
pascal@11674 444 jne notspc
pascal@11674 445 jcxz gotspc
pascal@11674 446 notspc:
pascal@11674 447 sub $'0', %al
pascal@11674 448 cmpb $10, %al # in 0..9 ?
pascal@11674 449 jb isx
pascal@11674 450 sub $'a'-'0'-10, %al
pascal@11674 451 cmpb $16, %al # in a..f ?
pascal@11674 452 jb isx
pascal@11674 453 cmpb $':'-'a'+10, %al
pascal@11674 454 popw %ax
pascal@11674 455 je getvalz # store segment in %bx
pascal@11674 456 xchgw %ax, %bx
pascal@11674 457 pushw %dx
pascal@11674 458 #ifdef CPU186
pascal@11674 459 shlw $12, %dx
pascal@11674 460 #else
pascal@11674 461 pushw %cx
pascal@11674 462 movb $12, %cl
pascal@11674 463 shlw %cl, %dx
pascal@11674 464 popw %cx
pascal@11674 465 #endif
pascal@11674 466 addw %dx, %bx
pascal@11674 467 popw %dx
pascal@11674 468 ret
pascal@11674 469
pascal@11674 470 crlf:
pascal@11674 471 .byte 13,10
pascal@11674 472 _end:
pascal@11674 473 buffer:
pascal@11674 474
pascal@11674 475 .org 510
pascal@11674 476 .byte 0x55, 0xAA
pascal@11674 477