cbios/mm.180

   1         page    255
   2         .z80
   3
   4
   5         public mmuinit
   6         public bnk2log,bnk2phy,hwl2phy,phy2log
   7         public isv_sw
   8         public b_ld_a,b_ld_hl,b_st_a,b_st_hl
   9
  10
  11         extrn @cbnk
  12         extrn ijphl
  13
  14
  15         maclib z180reg.inc
  16         maclib config.inc
  17
  18
  19 ;----------------------------------------------------------------------
  20 ; Memory Map 1:
  21 ;
  22 ;       Common  CAStart ..     0FFFF
  23 ;       Bank 0    00000 .. CAStart-1
  24 ;       Bank 1    10000 ..
  25 ;       Bank 2
  26 ;
  27 ; Memory Map 2:
  28 ;
  29 ;       Common    18000 .. 1BFFF        BANK1
  30 ;
  31 ;       Bank 0    00000 .. 0BFFF        0
  32 ;       Bank 1    0C000 .. 17FFF        1*BNK_SIZE
  33 ;       Bank 2    1C000 .. 27FFF        2*BNK_SIZE + CMN_SIZE
  34 ;       Bank 3    28000 .. 33FFF        3*BNK_SIZE + CMN_SIZE
  35 ;       Bank n                          n*BNK_SIZE + (n < 2) ? 0 : CMN_SIZE
  36 ;
  37 ;----------------------------------------------------------------------
  38
  39         cseg
  40
  41 mmuinit:
  42         ld      a,USR$CBAR
  43         out0    (cbar),a
  44         ret
  45
  46 ;--------------------------------------------------------------------
  47 ; Return the BBR value for the given bank number
  48 ;
  49 ; in  a: Bank number
  50 ; out a: bbr value
  51
  52    if 0 ; Memory Map 1
  53
  54 bnk2log:
  55         or      a               ;
  56         ret     z               ; Bank 0 is at physical address 0
  57
  58         dec     a               ;
  59         push    bc              ;
  60         ld      c,a             ;
  61         ld      b,BNK_SIZE      ;
  62         mlt     bc              ; bank size * bank number
  63         ld      a,c             ;
  64         add     a,10h           ; add bank0 + common
  65         pop     bc              ;
  66         ret                     ;
  67
  68    else ; Memory Map 2
  69
  70 bnk2log:
  71         or      a
  72         ret     z               ; Bank 0 is at physical address 0
  73
  74         push    bc
  75         ld      c,a             ;
  76         ld      b,BNK_SIZE      ;
  77         mlt     bc              ; bank size * bank number
  78         cp      2               ;
  79         ld      a,c             ;
  80         pop     bc
  81         ret     c
  82         add     a,CMN_SIZE
  83         ret
  84
  85     endif
  86
  87     if 0 ; table version
  88
  89         push    hl
  90         ld      hl,bnk_table    ;
  91         add     a,l             ;
  92         ld      l,a             ;
  93         jr      nc,$+3          ;
  94         inc     h               ;
  95         ld      a,(hl)          ;
  96         pop     hl
  97         ret
  98
  99     endif
 100
 101 ;--------------------------------------------------------------
 102
 103 ;in  hl: Log. Address
 104 ;     a: Bank number
 105 ;
 106 ;out ahl: Phys. (linear) Address
 107
 108
 109 bnk2phy:
 110         push    bc
 111         ld      c,a
 112         ld      a,h
 113         and     a,0f0h
 114         cp      CA*16
 115         ld      a,c
 116         pop     bc
 117         jr      c,b2p_banked
 118                                 ; address is in common
 119     if 0 ; Memory Map 1
 120         ld      a,0             ; base is 0
 121     else ; Memory Map 2
 122         ld      a,1             ; same as bank1
 123     endif
 124
 125 b2p_banked:
 126         call    bnk2log         ; get address base
 127
 128         ; fall thru
 129
 130 ;--------------------------------------------------------------
 131 ;
 132 ; hl: Log. Address
 133 ;  a: Bank base (bbr)
 134 ;
 135 ;            2           0       0
 136 ;            0   6       8       0
 137 ; hl              hhhhhhhhllllllll
 138 ;  a    +     bbbbbbbb
 139 ;
 140 ; OP: ahl = (a<<12) + (h<<8) + l
 141 ;
 142 ;out ahl: Phys. (linear) Address
 143
 144 log2phy:
 145         push    bc              ;
 146 l2p_i:
 147         ld      c,a             ;
 148         ld      b,16            ;
 149         mlt     bc              ; bc = a<<4
 150         ld      a,c             ;
 151         add     a,h             ;
 152         ld      h,a             ;
 153         ld      a,b             ;
 154         adc     a,0             ;
 155         pop     bc              ;
 156         ret                     ;
 157
 158 ;--------------------------------------------------------------
 159 ;
 160 ; hl: Log. Address
 161 ;
 162 ;
 163 ; OP: ahl = (bankbase<<12) + (h<<8) + l
 164 ;
 165 ;out ahl: Phys. (linear) Address
 166
 167
 168 hwl2phy:
 169         push    bc              ;
 170         in0     c,(cbar)        ;
 171         ld      a,h             ;
 172         or      00fh            ; log. addr in common1?
 173         cp      c
 174         jr      c,hlp_1
 175
 176         in0     a,(cbr)         ; yes, cbr is address base
 177         jr      hl2p_x
 178 hlp_1:
 179         ld      b,16            ; log. address in baked area?
 180         mlt     bc
 181         ld      a,h
 182         cp      c
 183         jr      c,hlp_2
 184         in0     a,(bbr)         ; yes, bbr is address base
 185         jr      hl2p_x
 186 hlp_2:
 187         xor     a               ; common1
 188 hl2p_x:
 189         jr      nz,l2p_i
 190
 191         pop     bc              ; bank part is 0, no translation
 192         ret                     ;
 193
 194
 195 ;--------------------------------------------------------------
 196 ; return logical bank 0 address for given physical address.
 197 ;
 198 ; in: ahl: pyhsical addres (20 bit)
 199 ; out  hl: logical address.
 200 ;          logical address is in bank 0 or common, no bank number returned
 201 ;
 202
 203 phy2log:
 204         or      a
 205         ret     z
 206
 207         push    bc
 208         push    hl
 209         ld      l,h
 210         ld      h,0
 211         ld      bc,-16*SYS$CBR
 212         add     hl,bc
 213         ld      h,l
 214         pop     bc
 215         ld      l,c
 216         pop     bc
 217         ret
 218
 219 ;--------------------------------------------------------------
 220 ; Trampoline for routines in banked ram.
 221 ; Switch stack pointer to "system" stack in top ram
 222 ; Save cbar
 223 ;
 224         cseg    ; common!
 225
 226         public  _b0call
 227
 228    if 0
 229
 230 _b0call:
 231         push    af
 232         in0     a,(bbr)
 233         jr      nz,b0c_doit
 234         pop     af
 235
 236         ex      (sp),hl                 ;16
 237         push    de
 238         ld      e,(hl)
 239         inc     hl
 240         ld      d,(hl)
 241         inc     hl
 242         ld      (b0c_fast_go),de
 243         pop     de
 244         ex      (sp),hl                 ;16
 245 b0c_fast_go equ $+1
 246         jp      0
 247
 248 b0c_doit:
 249         ld      (b0_save_hl),hl
 250         ld      (b0_save_de),de
 251         pop     hl
 252         ld      (b0_save_af),hl
 253
 254         pop     de                      ;get ptr to 'function address' in de
 255         ld      hl,2
 256         add     hl,de
 257         push    hl                      ;put return address on stack
 258
 259    if 0 ; link80
 260
 261         ld      hl,0
 262         add     hl,sp                   ;
 263         ld      a,h
 264         cp      high (bs$stack-bs$stack$size) ;link80 can't process this
 265         jr      nc,$ + 5                ;skip if stack allready in common bios ram
 266
 267    else
 268
 269         ld      hl,bs$stack-bs$stack$size
 270         ld      a,h
 271         dec     a
 272         ld      hl,0
 273         add     hl,sp                   ;
 274         cp      h
 275         jr      c,$ + 5                 ;skip if stack allready in common bios ram
 276    endif
 277         ld      sp,bs$stack             ;
 278
 279         push    hl                      ;save   user stack pointer
 280
 281         in0     h,(bbr)                 ;
 282         push    hl                      ;
 283         ld      hl,b0c_ret
 284         push    hl
 285         xor     a
 286         out0    (bbr),a                 ;
 287         ex      de,hl                   ;ptr
 288         ld      e,(hl)                  ;get 'function address'
 289         inc     hl                      ;
 290         ld      d,(hl)                  ;
 291         push    de                      ;put on (switched) stack
 292
 293         ld      hl,(b0_save_af)         ;get back users registers
 294         push    hl
 295         pop     af
 296         ld      de,(b0_save_de)
 297         ld      hl,(b0_save_hl)
 298         ret                             ;go to function
 299 b0c_ret:
 300         ld      (b0_save_hl),hl
 301
 302         pop     hl                      ;
 303         out0    (bbr),h                 ;
 304         pop     hl                      ;
 305         ld      sp,hl                   ;
 306         ld      hl,(b0_save_hl)
 307         ret                             ;
 308    else
 309
 310 _b0call:
 311         push    af
 312         ld      (b0_save_hl),hl
 313         ld      (b0_save_de),de
 314         pop     hl
 315         ld      (b0_save_af),hl
 316
 317         pop     de                      ;get ptr to 'function address' in de
 318         ld      hl,2
 319         add     hl,de
 320         push    hl                      ;put return address on stack
 321
 322    if 0 ; link80
 323
 324         ld      hl,0
 325         add     hl,sp                   ;
 326         ld      a,h
 327         cp      high (bs$stack-bs$stack$size) ;link80 can't process this
 328         jr      nc,$ + 5                ;skip if stack allready in common bios ram
 329
 330    else
 331
 332         ld      hl,bs$stack-bs$stack$size
 333         ld      a,h
 334         dec     a
 335         ld      hl,0
 336         add     hl,sp                   ;
 337         cp      h
 338         jr      c,$ + 5                 ;skip if stack allready in common bios ram
 339    endif
 340         ld      sp,bs$stack             ;
 341
 342         push    hl                      ;save   user stack pointer
 343
 344         in0     h,(bbr)                 ;
 345         push    hl                      ;
 346         ld      hl,b0c_ret
 347         push    hl
 348         xor     a
 349         out0    (bbr),a                 ;
 350         ex      de,hl                   ;ptr
 351         ld      e,(hl)                  ;get 'function address'
 352         inc     hl                      ;
 353         ld      d,(hl)                  ;
 354         push    de                      ;put on (switched) stack
 355
 356         ld      hl,(b0_save_af)         ;get back users registers
 357         push    hl
 358         pop     af
 359         ld      de,(b0_save_de)
 360         ld      hl,(b0_save_hl)
 361         ret                             ;go to function
 362 b0c_ret:
 363         ld      (b0_save_hl),hl
 364
 365         pop     hl                      ;
 366         out0    (bbr),h                 ;
 367         pop     hl                      ;
 368         ld      sp,hl                   ;
 369         ld      hl,(b0_save_hl)
 370         ret                             ;
 371    endif
 372
 373 b0_save_hl: dw  0
 374 b0_save_de: dw  0
 375 b0_save_af: dw  0
 376
 377
 378 ;--------------------------------------------------------------------
 379 ; Trampoline for interrupt routines in banked ram.
 380 ; Switch stack pointer to "system" stack in top ram
 381 ; Save bbr
 382
 383         cseg
 384
 385    if 0
 386
 387 isv_sw:                                 ;
 388         ex      (sp),hl                 ;save hl, 'return adr' in hl
 389         push    de                      ;
 390         push    af                      ;
 391         ex      de,hl                   ;'return address' in de
 392
 393   if 0
 394    if 0 ; link80
 395
 396         ld      hl,0
 397         add     hl,sp                   ;
 398         ld      a,h
 399         cp      high (bs$stack-bs$stack$size) ;link80 can't process this
 400         jr      nc,$ + 5                ;skip if stack allready in common bios ram
 401
 402    else
 403
 404         ld      hl,bs$stack-bs$stack$size
 405         ld      a,h
 406         dec     a
 407         ld      hl,0
 408         add     hl,sp                   ;
 409         cp      h
 410         jr      c,$ + 5                 ;skip if stack allready in common bios ram
 411    endif
 412         ld      sp,bs$stack             ;
 413   else
 414         ld      hl,0
 415         add     hl,sp
 416         ld      sp,istack
 417   endif
 418         push    hl                      ;save user stack pointer
 419         in0     h,(bbr)                 ;
 420         push    hl                      ;
 421         xor     a                       ;
 422         out0    (bbr),a                 ;
 423         ex      de,hl                   ;
 424         ld      e,(hl)                  ;
 425         inc     hl                      ;
 426         ld      d,(hl)                  ;
 427         ex      de,hl                   ;
 428         push    bc                      ;
 429         call    ijphl                   ;
 430
 431         pop     bc                      ;
 432         pop     hl                      ;
 433         out0    (bbr),h                 ;
 434         pop     hl                      ;
 435         ld      sp,hl                   ;
 436         pop     af                      ;
 437         pop     de                      ;
 438         pop     hl                      ;
 439         ei                              ;
 440         ret                             ;
 441
 442    else
 443
 444 isv_sw:                                 ;
 445         ex      (sp),hl                 ;save hl, 'return adr' in hl
 446
 447         ld      (i$stack),sp            ;save user stack pointer
 448         ld      sp,i$stack
 449         push    de                      ;
 450         push    bc                      ;
 451         push    af                      ;
 452         in0     a,(bbr)                 ;
 453         push    af                      ;
 454         xor     a                       ;
 455         out0    (bbr),a                 ;
 456         ld      e,(hl)                  ;
 457         inc     hl                      ;
 458         ld      d,(hl)                  ;
 459         ex      de,hl                   ;
 460         call    ijphl                   ;
 461
 462         pop     af                      ;
 463         out0    (bbr),a                 ;
 464         pop     af                      ;
 465         pop     bc                      ;
 466         pop     de                      ;
 467         ld      sp,(i$stack)            ;
 468         pop     hl                      ;
 469         ei                              ;
 470         ret                             ;
 471
 472    endif
 473
 474         public  i$stack
 475         rept    24
 476          db     '|'
 477         endm
 478 i$stack:
 479         dw      0
 480
 481         dseg
 482
 483 ;--------------------------------------------------------------------
 484 ; Load byte/word from user ram
 485 ;
 486 ;   de:  src address in users bank
 487 ; return
 488 ;    a:  value (byte)
 489 ;   hl:  value (word)
 490
 491 b_ld_a:
 492         push    hl
 493         or      a               ; clear carry == byte store
 494         jr      $+3
 495 b_ld_hl:
 496         scf                     ; set carry == word store
 497         push    af              ; save flag
 498         push    hl              ; make space on stack
 499
 500         ld      a,(@cbnk)
 501         ld      b,a             ; b = src bank
 502
 503         ld      hl,0
 504         ld      a,l
 505         ld      c,l             ; c = dst bank (0)
 506         add     hl,sp           ; hl = dst
 507         adc     a,1             ; a = count
 508         ex      de,hl
 509         call    dma_move
 510         ex      de,hl
 511         pop     hl
 512         pop     af
 513         ret     c
 514         ld      a,l
 515         pop     hl
 516         ret
 517
 518 ;--------------------------------------------------------------------
 519 ; Store byte/word to user ram
 520 ;
 521 ;   de:  dst address in users bank
 522 ;    a:  value (byte)
 523 ;   hl:  value (word)
 524
 525 b_st_a:
 526         push    hl
 527         ld      l,a
 528         or      a               ; clear carry == byte store
 529         jr      $+3
 530 b_st_hl:
 531         scf                     ; set carry == word store
 532         push    af              ; save flag
 533         push    hl              ; put value on stack
 534
 535         ld      a,(@cbnk)       ;
 536         ld      c,a             ; c = dst bank
 537         ld      a,0
 538         ld      l,a
 539         ld      h,a
 540         ld      b,a             ; b = src bank (0)
 541         add     hl,sp           ; hl = src
 542         adc     a,1             ; a = count
 543
 544         call    dma_move
 545
 546         pop     hl              ; restore value
 547         pop     af              ; carry
 548         ret     c
 549         pop     hl
 550         ret
 551
 552 ;--------------------------------------------------------------------
 553 ;
 554 ;    hl: src
 555 ;    de: dst
 556 ;     b: src bank
 557 ;     c: dst bank
 558 ;     a: count
 559
 560 dma_move:
 561         out0    (bcr0l),a       ; setup DMA count
 562         xor     a
 563         out0    (bcr0h),a
 564
 565         push    hl
 566         ld      a,b
 567         call    bnk2phy
 568         out0    (sar0l),l       ; setup DMA src address
 569         out0    (sar0h),h
 570         out0    (sar0b),a
 571
 572         ld      l,e
 573         ld      h,d
 574         ld      a,c
 575         call    bnk2phy
 576         out0    (dar0l),l       ; setup DMA dst address
 577         out0    (dar0h),h
 578         out0    (dar0b),a
 579
 580         ld      a,M_MMOD        ; DMA burst mode
 581         out0    (dmode),a
 582         ld      a,M_DE0+M_NDWE1 ; enable DMA0
 583         out0    (dstat),a       ; move ...
 584         pop     hl
 585         ret
 586
 587
 588 ;====================================================================
 589
 590         cseg
 591
 592   if 0
 593
 594 ;--------------------------------------------------------------------
 595 ; Return the BBR value for the given bank number
 596
 597 bnk2bbr:
 598         or      a               ; 4
 599         ret     z               ; 5/10 | 11             14
 600
 601         push    bc              ;11 | 11
 602         ld      b,a             ; 4
 603         ld      c,CA            ; 6
 604         mlt     bc              ;17                         >45
 605         ld      a,c             ; 4
 606         add     a,10h           ; 6
 607         pop     bc              ; 9 | 10
 608         ret                     ; 9 | 10                76
 609
 610         push    ix              ;2 / 14 | 15
 611         ld      ix,bnktbl       ;4 / 12 | 14
 612         ld      ($+3+2),a       ;3 / 15 | 19
 613         ld      a,(ix+0)        ;3 / 14 | 19
 614         pop     ix              ;2 / 12 | 14
 615         ret                     ;1 /  9 | 10            15 / 76|91
 616
 617         push    hl              ;1 / 11 | 11
 618         ld      hl,bnktbl       ;3 /  9 | 10
 619         add     a,l             ;1 /  4 | 4
 620         ld      l,a             ;1 /  4 | 4
 621         ld      a,0             ;1 /  6 | 7
 622         adc     a,h             ;1 /  4 | 4
 623         ld      h,a             ;1 /  4 | 4
 624         ld      a,(hl)          ;1 /  6 | 7
 625         pop     hl              ;1 /  9 | 10
 626         ret                     ;1 /  9 | 10            12 / 66|71
 627
 628         push    hl              ;1 / 11 | 11
 629         add     a,low bnktbl    ;2 /  6 | 7
 630         ld      l,a             ;1 /  4 | 4
 631         ld      a,0             ;1 /  6 | 7
 632         adc     a,high bnktbl   ;2 /  6 | 7
 633         ld      h,a             ;1 /  4 | 4
 634         ld      a,(hl)          ;1 /  6 | 7
 635         pop     hl              ;1 /  9 | 10
 636         ret                     ;1 /  9 | 10            11 / 61|67
 637
 638   endif
 639
 640
 641         cseg
 642         public  bs$stack
 643
 644         rept bs$stack$size
 645          db     '|'
 646         endm
 647 bs$stack:
 648         dw      0
 649
 650         end