io Programmo 23/IOPROG_23.ISO/SOFT/ASM/GRDBDL17.ZIP/PCI.ASM

Assembly Source File | 1998-10-26 | 5.5 KB | 220 lines

;
; GRDB
;
; Copyright(c) LADsoft
;
; David Lindauer, [e-mail]
;
; this module donated by:
;
;  Trung Nguyen <[e-mail]>
;
; a BIOS developer at texas micro inc.
;
;
; PCI.ASM
;
; Function: PCI commands
;
;
    ;MASM MODE
    .MODEL SMALL
    .386

include  eprints.inc
include  einput.inc
include  emtrap.inc

IODELAY MACRO
        out     0EDh, al
ENDM

    PUBLIC pci

    .data

    .CODE
pci    PROC
    lodsb
    cmp    al,'?'        ; verify subcommand
        jz      pfaCmd          ; PFA command
    call    ReadNumber    ; PFA
    jc    pciErr
        cmp     eax, 0FFFFh     ; Q:Valid PFA
        ja      pciErr          ;   N:
        mov     ebx, eax
    call    WadeSpace    ;
    jz    pciErr
    call    ReadNumber    ; Reg
    jc    pciErr
        cmp     eax, 0FFh       ; Q:Valid Reg
        ja      pciErr          ;   N:
        mov     ah, al
        push    ax
    call    WadeSpace    ;
        pop     ax
    jnz    pciDoWrite
        call    PciByteRead
        push    ax
    call    crlf
        pop     ax
        call    PrintByte
        jmp     pciNoErr

pciDoWrite:
        push    ax
    call    ReadNumber    ; Value
    jc    pciErr
        cmp     eax, 0FFh       ; Q:Valid val
        ja      pciErr          ;   N:
        mov     cl, al
        pop     ax
        mov     al, cl
        push    ax
    call    WadeSpace    ;
        pop     ax
    jnz    pciErr
        call    pciByteWrite
        jmp     pciNoErr

pfaCmd:
    call    WadeSpace    ; get operator
    jz    pciErr
        xor     ebx, ebx
    call    ReadNumber    ; Bus
    jc    pciErr
        cmp     eax, 0FFh       ; Q:Valid Bus
        ja      pciErr          ;   N:
        mov     bl, al          ;   Y: Get bus
        shl     bx, 8
    call    WadeSpace    ; get operator
    jz    pciErr
    call    ReadNumber    ; Dev
    jc    pciErr
        cmp     eax, 01Fh       ; Q:Valid Dev
        ja      pciErr          ;   N:
        mov     bl, al          ;   Y: Get Dev
        shl     bl, 3
    call    WadeSpace    ; get operator
    jz    pciErr
    call    ReadNumber    ; Func
    jc    pciErr
        cmp     eax, 07h        ; Q:Valid Func
        ja      pciErr          ;   N:
        or      bl, al
    call    WadeSpace
    jnz    pciErr
    call    crlf
        mov     ax, bx
        call    PrintWord

pciNoErr:
        clc
        jmp     pciDone

pciErr:
        stc

pciDone:
        ret
pci    endp


;----------------------------------------------------------------------------
;       PciByteRead -
;       This proc will read the byte from the register and device
;
;       Entry:  BX = PFA
;                    Bit<15..8>=Bus
;                    Bit<7...3>=Dev
;                    Bit<2..0>=Func
;               AH = Reg
;       Exit:
;               AL = register contents.
;       Affected registers:
;               AL is destroyed, all other registers are preserved.
;
PciByteRead PROC
        push    cx
        push    dx
        push    eax
        mov     ch, ah          ; Save register in CH
        mov     eax,0800000h
        or      ax, bx          ; Get PFA
        shl     eax, 8          ; Make room for register
        mov     al, ch          ; Place register info in location
        and     al,0FCh         ; Strip off alignment data.
        mov     dx,0CF8h        ;
        out     dx,eax
        IODELAY
        call    PointToByte     ; Align the PCI data port to out byte.
        in      al,dx           ; Fetch the data.
        IODELAY
        mov     cl, al          ; Save data first
        pop     eax
        mov     al, cl          ; Place data back
        pop     dx
        pop     cx
        ret
PciByteRead ENDP

;----------------------------------------------------------------------------
;       PciByteWrite -
;       This proc will write a byte to the register and device
;
;       Entry:  BX = PFA
;                    Bit<15..8>=Bus
;                    Bit<7...3>=Dev
;                    Bit<2..0>=Func
;               AH = Reg
;               AL = Value
;       Exit:
;               None.
;       Affected registers:
;               All registers are preserved.
;
PciByteWrite PROC
        push    cx
        push    dx
        push    eax
        mov     cx, ax          ; Save register and value in CX
        mov     eax,0800000h
        or      ax, bx          ; Get PFA
        shl     eax, 8          ; Make room for register
        mov     al, ch          ; Place register info in location
        and     al,0FCh         ; Strip off alignment data.
        mov     dx,0CF8h        ;
        out     dx,eax
        IODELAY
        call    PointToByte     ; Align the PCI data port to out byte.
        mov     al, cl          ; Get value back
        out     dx, al          ; BlastIT!!!!
        IODELAY
        pop     eax
        pop     dx
        pop     cx
        ret
PciByteWrite ENDP

;----------------------------------------------------------------------------
;       PointToByte
;       This proc provides the appropriate PCI IO port address to properly
;       access data in the PCI CFG space.
;       Entry:
;               CH = Register to use.
;       Exit:
;               DX = PCI data port IO address.
;       Affected registers:
;               DX is modified, all other registers are preserved.
;
PointToByte PROC
        push    cx
        and     cx,0300h        ; Strip all but byte information.
        xchg    ch, cl          ; Swap the LSB and MSB
        mov     dx,0CFCh        ; Base PCI IO port.
        add     dx,cx           ; Point to our register.
        pop     cx
        ret
PointToByte ENDP

end