_pmdos.asm

AT91RM9200-U-Boot at91rm9200u-boot移植源代码

        popfd
        pop     ecx
        pop     ebx
        pop     eax
else
        pushf
ifdef   USE_NASM
        call far dword [_PM_prevKey15]
else
        call    [_PM_prevKey15]
endif
endif
@@Exit: pop     es
        pop     ds
ifdef flatmodel
        retf    4
else
        retf    2
endif

cprocend

;----------------------------------------------------------------------------
; PM_breakISR - Control Break interrupt subroutine dispatcher
;----------------------------------------------------------------------------
; Hardware interrupt handler for the Ctrl-Break interrupt. We simply set
; the Ctrl-Break flag to a 1 and leave (note that this is accessed through
; a far pointer, as it may well be located in conventional memory).
;----------------------------------------------------------------------------
cprocfar    _PM_breakISR

        sti
        push    ds              ; Save value of DS
        push    es
        push    _bx

        LOAD_DS                 ; Load DS register
ifdef flatmodel
        mov     ebx,[_PM_ctrlBPtr]
else
        les     bx,[_PM_ctrlBPtr]
endif
        mov     [UINT _ES _bx],1

; Run alternate break handler code if installed

        cmp     [CPTR _PM_breakHandler],0
        je      @@Exit

        pushad
        mov     _ax,1
        push    _ax
        call    [CPTR _PM_breakHandler] ; Call C code
        pop     _ax
        popad

@@Exit: pop     _bx
        pop     es
        pop     ds
        iret                    ; Return from interrupt

cprocend

;----------------------------------------------------------------------------
; int PM_ctrlBreakHit(int clearFlag)
;----------------------------------------------------------------------------
; Returns the current state of the Ctrl-Break flag and possibly clears it.
;----------------------------------------------------------------------------
cprocstart  PM_ctrlBreakHit

        ARG     clearFlag:UINT

        enter_c
        pushf                   ; Save interrupt status
        push    es
ifdef flatmodel
        mov     ebx,[_PM_ctrlBPtr]
else
        les     bx,[_PM_ctrlBPtr]
endif
        cli                     ; No interrupts thanks!
        mov     _ax,[_ES _bx]
        test    [BYTE clearFlag],1
        jz      @@Done
        mov     [UINT _ES _bx],0

@@Done: pop     es
        popf                    ; Restore interrupt status
        leave_c
        ret

cprocend

;----------------------------------------------------------------------------
; PM_ctrlCISR - Control Break interrupt subroutine dispatcher
;----------------------------------------------------------------------------
; Hardware interrupt handler for the Ctrl-C interrupt. We simply set
; the Ctrl-C flag to a 1 and leave (note that this is accessed through
; a far pointer, as it may well be located in conventional memory).
;----------------------------------------------------------------------------
cprocfar    _PM_ctrlCISR

        sti
        push    ds              ; Save value of DS
        push    es
        push    _bx

        LOAD_DS                 ; Load DS register
ifdef flatmodel
        mov     ebx,[_PM_ctrlCPtr]
else
        les     bx,[_PM_ctrlCPtr]
endif
        mov     [UINT _ES _bx],1

; Run alternate break handler code if installed

        cmp     [CPTR _PM_breakHandler],0
        je      @@Exit

        pushad
        mov     _ax,0
        push    _ax
        call    [CPTR _PM_breakHandler] ; Call C code
        pop     _ax
        popad

@@Exit: pop     _bx
        pop     es
        pop     ds
        iret                    ; Return from interrupt
        iretd

cprocend

;----------------------------------------------------------------------------
; int PM_ctrlCHit(int clearFlag)
;----------------------------------------------------------------------------
; Returns the current state of the Ctrl-C flag and possibly clears it.
;----------------------------------------------------------------------------
cprocstart  PM_ctrlCHit

        ARG     clearFlag:UINT

        enter_c
        pushf                   ; Save interrupt status
        push    es
ifdef flatmodel
        mov     ebx,[_PM_ctrlCPtr]
else
        les     bx,[_PM_ctrlCPtr]
endif
        cli                     ; No interrupts thanks!
        mov     _ax,[_ES _bx]
        test    [BYTE clearFlag],1
        jz      @@Done
        mov     [UINT _ES _bx],0

@@Done:
        pop     es
        popf                    ; Restore interrupt status
        leave_c
        ret

cprocend

;----------------------------------------------------------------------------
; PM_criticalISR - Control Error handler interrupt subroutine dispatcher
;----------------------------------------------------------------------------
; Interrupt handler for the MSDOS Critical Error interrupt, to dispatch
; control to high level C based subroutines. We save the state of all
; registers in this routine, and switch to a local stack. We also pass
; the values of the AX and DI registers to the as pointers, so that the
; values can be modified before returning to MSDOS.
;----------------------------------------------------------------------------
cprocfar    _PM_criticalISR

        sti
        push    ds              ; Save value of DS
        push    es
        push    _bx             ; Save register values changed
        cld                     ; Clear direction flag

        LOAD_DS                 ; Load DS register
ifdef flatmodel
        mov     ebx,[_PM_critPtr]
else
        les     bx,[_PM_critPtr]
endif
        mov     [_ES _bx],ax
        mov     [_ES _bx+2],di

; Run alternate critical handler code if installed

        cmp     [CPTR _PM_critHandler],0
        je      @@NoAltHandler

        pushad
        push    _di
        push    _ax
        call    [CPTR _PM_critHandler]  ; Call C code
        _add    sp,4,8
        popad

        pop     _bx
        pop     es
        pop     ds
        iret                    ; Return from interrupt

@@NoAltHandler:
        mov     ax,3            ; Tell MSDOS to fail the operation
        pop     _bx
        pop     es
        pop     ds
        iret                    ; Return from interrupt

cprocend

;----------------------------------------------------------------------------
; int PM_criticalError(int *axVal,int *diVal,int clearFlag)
;----------------------------------------------------------------------------
; Returns the current state of the critical error flags, and the values that
; MSDOS passed in the AX and DI registers to our handler.
;----------------------------------------------------------------------------
cprocstart  PM_criticalError

        ARG     axVal:DPTR, diVal:DPTR, clearFlag:UINT

        enter_c
        pushf                   ; Save interrupt status
        push    es
ifdef flatmodel
        mov     ebx,[_PM_critPtr]
else
        les     bx,[_PM_critPtr]
endif
        cli                     ; No interrupts thanks!
        xor     _ax,_ax
        xor     _di,_di
        mov     ax,[_ES _bx]
        mov     di,[_ES _bx+2]
        test    [BYTE clearFlag],1
        jz      @@NoClear
        mov     [ULONG _ES _bx],0
@@NoClear:
        _les    _bx,[axVal]
        mov     [_ES _bx],_ax
        _les    _bx,[diVal]
        mov     [_ES _bx],_di
        pop     es
        popf                    ; Restore interrupt status
        leave_c
        ret

cprocend

;----------------------------------------------------------------------------
; void PM_setMouseHandler(int mask, PM_mouseHandler mh)
;----------------------------------------------------------------------------
cprocstart  _PM_setMouseHandler

        ARG     mouseMask:UINT

        enter_c
        push    es

        mov     ax,0Ch          ; AX := Function 12 - install interrupt sub
        mov     _cx,[mouseMask] ; CX := mouse mask
        mov     _dx,offset _PM_mouseISR
        push    cs
        pop     es              ; ES:_DX -> mouse handler
        int     33h             ; Call mouse driver

        pop     es
        leave_c
        ret

cprocend

ifdef flatmodel

;----------------------------------------------------------------------------
; void PM_mousePMCB(void)
;----------------------------------------------------------------------------
; Mouse realmode callback routine. Upon entry to this routine, we recieve
; the following from the DPMI server:
;
;   Entry:  DS:_SI  -> Real mode stack at time of call
;           ES:_DI  -> Real mode register data structure
;           SS:_SP  -> Locked protected mode stack to use
;----------------------------------------------------------------------------
cprocfar    _PM_mousePMCB

        pushad
        mov     eax,[es:_di+1Ch]    ; Load register values from real mode
        mov     ebx,[es:_di+10h]
        mov     ecx,[es:_di+18h]
        mov     edx,[es:_di+14h]
        mov     esi,[es:_di+04h]
        mov     edi,[es:_di]
        call    _PM_mouseISR        ; Call the mouse handler
        popad

        mov     ax,[ds:_si]
        mov     [es:_di+2Ah],ax     ; Plug in return IP address
        mov     ax,[ds:_si+2]
        mov     [es:_di+2Ch],ax     ; Plug in return CS value
        add     [WORD es:_di+2Eh],4 ; Remove return address from stack
        iret                        ; Go back to real mode!

cprocend

;----------------------------------------------------------------------------
; void PM_int10PMCB(void)
;----------------------------------------------------------------------------
; int10 realmode callback routine. Upon entry to this routine, we recieve
; the following from the DPMI server:
;
;   Entry:  DS:ESI  -> Real mode stack at time of call
;           ES:EDI  -> Real mode register data structure
;           SS:ESP  -> Locked protected mode stack to use
;----------------------------------------------------------------------------
cprocfar        _PM_int10PMCB

        pushad
        push    ds
        push    es
        push    fs

        pushfd
        pop     eax
        mov     [es:edi+20h],ax     ; Save return flag status
        mov     ax,[ds:esi]
        mov     [es:edi+2Ah],ax     ; Plug in return IP address
        mov     ax,[ds:esi+2]
        mov     [es:edi+2Ch],ax     ; Plug in return CS value
        add     [WORD es:edi+2Eh],4 ; Remove return address from stack

; Call the install int10 handler in protected mode. This function gets called
; with DS set to the current data selector, and ES:EDI pointing the the
; real mode DPMI register structure at the time of the interrupt. The
; handle must be written in assembler to be able to extract the real mode
; register values from the structure

        push    es
        pop     fs                  ; FS:EDI -> real mode registers
        LOAD_DS
        NEWSTK  Int10Stack          ; Switch to local stack

        call    [_PM_int10Handler]

        RESTSTK Int10Stack          ; Restore previous stack
        pop     fs
        pop     es
        pop     ds
        popad
        iret                        ; Go back to real mode!

cprocend

endif

cpublic _PM_pmdosCodeEnd

endcodeseg  _pmdos

        END                     ; End of module