Changeset 557 in xtideuniversalbios


Ignore:
Timestamp:
Jun 19, 2013, 6:47:58 PM (11 years ago)
Author:
aitotat@…
google:author:
aitotat@gmail.com
Message:

Changes to XTIDE Universal BIOS:

  • Finally fixed the Windows 98 problem (blue sceen when loading hsflop.pdr). Windows didn't like INT 13 handler being changed.
File:
1 edited

Legend:

Unmodified
Added
Removed
  • trunk/XTIDE_Universal_BIOS/Src/Handlers/Int13h.asm

    r556 r557  
    103103%ifdef MODULE_DRIVEXLATE
    104104    call    DriveXlate_ToOrBack
    105     mov     [RAMVARS.xlateVars+XLATEVARS.bXlatedDrv], dl
    106105%endif
    107106    call    FindDPT_ForDriveNumberInDL  ; DS:DI points to our DPT, or NULL if not our drive
     
    166165UnsupportedFunction:
    167166Int13h_DirectCallToAnotherBios:
    168     call    ExchangeCurrentInt13hHandlerWithOldInt13hHandler
     167%ifdef MODULE_DRIVEXLATE
     168    ; Disable drive number translations in case of recursive INT 13h calls
     169    mov     [RAMVARS.xlateVars+XLATEVARS.bXlatedDrv], dl
     170    push    WORD [RAMVARS.xlateVars+XLATEVARS.wFDandHDswap]
     171    mov     WORD [RAMVARS.xlateVars+XLATEVARS.wFDandHDswap], 8000h  ; No translation
     172%endif
     173
     174    push    bp                          ; Store offset to IDEPACK (SS:SP now points it)
     175
     176    ; Simulate INT by pushing flags and return address
     177    push    WORD [bp+IDEPACK.intpack+INTPACK.flags]
     178    popf
     179    pushf                               ; Simulate INT by pushing flags
     180    push    cs
     181    ePUSH_T di, .ReturnFromAnotherBios  ; Can not corrupt flags
     182
     183    ; Push old INT 13h handler and restore registers
     184    push    WORD [RAMVARS.fpOldI13h+2]
     185    push    WORD [RAMVARS.fpOldI13h]
    169186    mov     bx, [bp+IDEPACK.intpack+INTPACK.bx]
    170187    mov     di, [bp+IDEPACK.intpack+INTPACK.di]
    171188    mov     ds, [bp+IDEPACK.intpack+INTPACK.ds]
    172     push    WORD [bp+IDEPACK.intpack+INTPACK.flags]
    173     popf
    174     push    bp
    175189    mov     bp, [bp+IDEPACK.intpack+INTPACK.bp]
    176 
    177     test    dl, dl
    178     js      SHORT .CallHardDiskHandler
    179     int     BIOS_DISKETTE_INTERRUPT_40h ; Windows 98 requires we call INT 40h for floppy drives (reason unknown)
    180     SKIP2B  bp                          ; Skip INT 13h
    181 .CallHardDiskHandler:
    182     int     BIOS_DISK_INTERRUPT_13h     ; Can safely do as much recursion as it wants
    183 
    184     ; Store returned values to INTPACK
    185     pop     bp  ; Standard INT 13h functions never uses BP as return register
     190    retf                                ; "Return" to old INT 13h
     191.ReturnFromAnotherBios:
     192
     193%if 0
     194    ; We need to restore our pointer to IDEPACK but we cannot corrupt any register
     195    push    ax                          ; Dummy WORD
     196    cli
     197    xchg    bp, sp
     198    mov     [bp], sp                    ; Replace dummy WORD with returned BP
     199    mov     sp, [bp+2]                  ; Load offset to IDEPACK
     200    xchg    sp, bp
     201    sti                                 ; We would have set IF anyway when exiting INT 13h
     202    pop     WORD [bp+IDEPACK.intpack+INTPACK.bp]
     203%endif
     204    ; Actually we can corrupt BP since no standard INT 13h function uses it as return
     205    ; register. Above code is kept here just in case if there is some non-standard function.
     206    ; POP BP below also belongs to the above code.
     207    pop     bp                          ; Clean IDEPACK offset from stack
     208
     209    ; Store remaining returned values to INTPACK
    186210%ifdef USE_386
     211; We do not use GS or FS at the moment
    187212;   mov     [bp+IDEPACK.intpack+INTPACK.gs], gs
    188213;   mov     [bp+IDEPACK.intpack+INTPACK.fs], fs
     
    205230
    206231%ifdef MODULE_DRIVEXLATE
     232    ; Restore drive number translation back to what it was
     233    pop     WORD [RAMVARS.xlateVars+XLATEVARS.wFDandHDswap]
    207234    cmp     dl, [RAMVARS.xlateVars+XLATEVARS.bXlatedDrv]    ; DL is still drive number?
    208     je      SHORT .ExchangeInt13hHandlers
     235    je      SHORT Int13h_ReturnFromHandlerAfterStoringErrorCodeFromAH
    209236    mov     [bp+IDEPACK.intpack+INTPACK.dl], dl ; Something is returned in DL
    210 ALIGN JUMP_ALIGN
    211 .ExchangeInt13hHandlers:
    212 %endif
    213 
    214 %ifdef USE_186
    215     push    Int13h_ReturnFromHandlerAfterStoringErrorCodeFromAH
    216     jmp     SHORT ExchangeCurrentInt13hHandlerWithOldInt13hHandler
    217 %else
    218     call    ExchangeCurrentInt13hHandlerWithOldInt13hHandler
     237%endif
    219238    jmp     SHORT Int13h_ReturnFromHandlerAfterStoringErrorCodeFromAH
    220 %endif
    221239
    222240
     
    295313ALIGN JUMP_ALIGN
    296314Int13h_CallPreviousInt13hHandler:
    297     call    ExchangeCurrentInt13hHandlerWithOldInt13hHandler
    298     int     BIOS_DISK_INTERRUPT_13h
    299 ;;;  fall-through to ExchangeCurrentInt13hHandlerWithOldInt13hHandler
    300 
    301 ;--------------------------------------------------------------------
    302 ; ExchangeCurrentInt13hHandlerWithOldInt13hHandler
    303 ;   Parameters:
    304 ;       DS:     RAMVARS segment
    305 ;   Returns:
    306 ;       Nothing
    307 ;   Corrupts registers:
    308 ;       Nothing
    309 ;       Note: Flags are preserved
    310 ;--------------------------------------------------------------------
    311 ALIGN JUMP_ALIGN
    312 ExchangeCurrentInt13hHandlerWithOldInt13hHandler:
    313     push    es
    314     push    si
    315     LOAD_BDA_SEGMENT_PRESERVE_FLAGS_TO  es, si
    316     mov     si, [RAMVARS.fpOldI13h]
    317     cli
    318     xchg    si, [es:BIOS_DISK_INTERRUPT_13h*4]
    319     mov     [RAMVARS.fpOldI13h], si
    320     mov     si, [RAMVARS.fpOldI13h+2]
    321     xchg    si, [es:BIOS_DISK_INTERRUPT_13h*4+2]
    322     sti
    323     mov     [RAMVARS.fpOldI13h+2], si
    324     pop     si
    325     pop     es
     315    pushf                       ; Simulate INT by pushing flags
     316    call far [RAMVARS.fpOldI13h]
    326317    ret
    327318
Note: See TracChangeset for help on using the changeset viewer.