|
|
title "PCI bus Support Assembley Code";++;; Copyright (c) 1989 Microsoft Corporation;; Module Name:;; hwpcia.asm;; Abstract:;; Calls the PCI rom function to determine what type of PCI; support is prsent, if any.;; Base code provided by Intel;; Author:;;--
.386p .xlistinclude hwpci.inc .list
if DBG extrn _BlPrint:PROCendif
_DATA SEGMENT PARA USE16 PUBLIC 'DATA'
if DBGcr equ 11
PciBIOSSig db 'PCI: Scanning for "PCI "', cr, 0PciBIOSSigNotFound db 'PCI: BIOS "PCI " not found', cr, 0
PciInt db 'PCI: Calling PCI_BIOS_PRESENT', cr, 0PciIntFailed db 'PCI: PCI_BIOS_PRESENT returned carry', cr, 0PciIntAhFailed db 'PCI: PCI_BIOS_PRESENT returned bad AH value', cr, 0PciIDFailed db 'PCI: PCI_BIOS_PRESENT invalid PCI id', cr, 0PciInt10IdFailed db 'PCI: PCI10_BIOS_PRESENT invalid PCI id', cr, 0
PciFound db 'PCI BUS FOUND', cr, 0
PciBadRead db 'PCI BAD READ', cr, 0endif
_DATA ends
_TEXT SEGMENT PARA USE16 PUBLIC 'CODE' ASSUME CS: _TEXT
;++;; BOOLEAN; HwGetPciSystemData (; PPCI_SYSTEM_DATA PciSystemData; );; Routine Description:;; This function retrieves the PCI System Data;; Arguments:;; PciSystemData - Supplies a pointer to the structure which will; receive the PCI System Data.;; Return Value:;; True - PCI System Detected and System Data valid; False - PCI System Not Detected;;--
SystemInfoPointer equ [bp + 4]BiosDateFound equ [bp + 6]
public _HwGetPciSystemData_HwGetPciSystemData proc push bp ; The following INT 15H destroies mov bp, sp ; ALL the general registers. push si push di push bx;; Set for no PCI buses present;
mov bx, SystemInfoPointer mov byte ptr [bx].NoBuses, 0
;; Is the BIOS date >= 11/01/92? If so, make the int-1a call; push ds cmp byte ptr [BiosDateFound], 0 jnz gpci00
;; A valid BIOS date was not found, check for "PCI " in bios code.;
if DBG push offset PciBIOSSig call _BlPrint add sp, 2endif mov bx, 0f000h mov ds, bx mov bx, 0fffch
spci05: cmp dword ptr ds:[bx], ' ICP' ; 'PCI ' found at this addr? je short gpci00 ; found
dec bx ; next location jnz short spci05 ; loop jmp spci_notfound ; wrapped, all done - not found
gpci00: pop ds
if DBG push offset PciInt call _BlPrint add sp, 2endif;; Check for a PCI system. Issue the PCI Present request.;
mov ax, PCI_BIOS_PRESENT ; Real Mode Presence Request int PCI_INTERFACE_INT ; Just Do It!
jc gpci10 ; Carry Set => No PCI
cmp ah, 0 ; If PCI Present AH == 0 jne gpci12 ; AH != 0 => No PCI
cmp edx, " ICP" ; "PCI" Backwards (with a trailing space) jne gpci14 ; PCI Signature in EDX => PCI Exists
;; Found PCI BIOS Version > 1.0;; The only thing left to do is squirrel the data away for the caller;
mov dx, bx ; Save revision level mov bx, SystemInfoPointer ; Get caller's Pointer
mov byte ptr [bx].MajorRevision, dh mov byte ptr [bx].MinorRevision, dl inc cl ; NoBuses = LastBus+1
if 0;; Some PIC BIOS returns very large number of NoBuses. As a work-; around we mask the value to 16, unless the BIOS also return CH as; neg cl then we believe it.;
cmp cl, 16 jbe short @f
neg ch inc ch cmp cl, ch je short @f
mov cl, 16@@:endif
mov byte ptr [bx].NoBuses, cl mov byte ptr [bx].HwMechanism, al jmp Done ; We're done
if DBGgpci10: mov ax, offset PciIntFailed jmp short gpci_oldbios
gpci12: mov ax, offset PciIntAhFailed jmp short gpci_oldbios
gpci14: mov ax, offset PciIDFailedgpci_oldbios: push ax call _BlPrint add sp, 2
else
gpci10:gpci12:gpci14:
endif
; ; Look for BIOS Version 1.0, This has a different function # ;
mov ax, PCI10_BIOS_PRESENT ; Real Mode Presence Request int PCI_INTERFACE_INT ; Just Do It!
; Version 1.0 has "PCI " in dx and cx, the Version number in ax, and the ; carry flag cleared. These are all the indications available. ;
cmp dx, "CP" ; "PC" Backwards jne gpci50 ; PCI Signature not in DX & CX => No PCI
cmp cx, " I" ; "I " Backwards jne gpci50 ; PCI Signature not in EDX => No PCI
;; Found PCI BIOS Version 1.0;; The only thing left to do is squirrel the data away for the caller;
mov bx, SystemInfoPointer ; Get caller's Pointer
mov byte ptr [bx].MajorRevision, ah mov byte ptr [bx].MinorRevision, al
; ; The Version 1.0 BIOS is only on early HW that had couldn't support ; Multi Function devices or multiple bus's. So without reading any ; device data, mark it as such. ;
mov byte ptr [bx].HwMechanism, 2 mov byte ptr [bx].NoBuses, 1 jmp Done
spci_notfound: pop ds ; restore dsif DBG push offset PciBIOSSigNotFound call _BlPrint add sp, 2endif jmp gpci_exit
if DBGgpci50: push offset PciInt10IdFailed jmp Done10
Done: push offset PciFoundDone10: call _BlPrint add sp, 2
else
; non-debug no printsgpci50:Done:
endif
gpci_exit: pop bx pop di pop si pop bp ret
_HwGetPciSystemData endp
RouteBuffer equ [bp + 4]ExclusiveIRQs equ [bp + 8]
public _HwGetPciIrqRoutingOptions_HwGetPciIrqRoutingOptions proc push bp mov bp, sp ; Create 'C' stack frame.
push ebx push edi push esi ; Save registers used.
push es push ds
xor edi, edi les di, RouteBuffer mov bx, 0f000h mov ds, bx xor ebx, ebx mov ax, 0B10Eh
int PCI_INTERFACE_INT
pop ds pop es
mov di, ExclusiveIRQs mov [di], bx
mov al, ah
pop esi ; Restore registers. pop edi pop ebx pop bp ret
_HwGetPciIrqRoutingOptions endp
Bus equ [bp + 4]Device equ [bp + 6]Function equ [bp + 8]RegOffset equ [bp + 10]DataRead equ [bp + 12]
public _HwGetPciConfigurationDword_HwGetPciConfigurationDword proc push bp mov bp, sp ; Create 'C' stack frame.
push ebx push ecx push edi push esi ; Save registers used.
push es push ds
mov bl, Device shl bl, 3 or bl, Function mov bh, Bus mov di, RegOffset mov ax, 0B10Ah
int PCI_INTERFACE_INT
jc gbadread ; Carry Set => Read failed pop ds pop es
mov di, DataRead mov [di], ecx
mov al, ah jmp greaddone
if DBGgbadread: push offset PciBadRead call _BlPrint add sp, 2 mov al, 087helsegbadread:endifgreaddone: pop esi ; Restore registers. pop edi pop ecx pop ebx pop bp ret
_HwGetPciConfigurationDword endp
_TEXT ends end
|
