pci.txt

比较详尽的VGA端口寄存器的文档

There are two configuration methods, depending on the PCI chipsets used:

Configuration Type 1:

CF8h D(R/W):
bit   0-7  Index into the configuration space to read/write at CFCh
    11-15  Card ID (0 - 31)
    16-19  PCI Bus ID (0 - 15)
       31  Set to enable the PCI bus configuration space

CFCh D(R/W):
bit  0-31  The index register identified by the PCI bus/card ID/Index in CF8h
           can be accessed here.


Configuration Type 2:

CF8h (R/W):
bit   7  Set to select the PCI configuration space

CFAh (R/W):
bit 0-?  Bus select ?


Finding the PCI devices:

  PCItype:=0;
  outp($CF8,0);
  outp($CFA,0);
  if (inp($CF8)=0) and (inp($CFA)=0) then PCItype:=2
  else begin
    tmp=inpl($CF8);
    outpl($CF8,$80000000);
    if inpl($CF8)=$80000000 then PCItype:=1;
    outpl($CF8,tmp);
  end;
  case PCItype of
    1:begin   {PCI type 1}
        for i:=0 to 511 do
        begin
          outpl($CF8,$80000000+i*longint(2048));
          tmp:=inpl($CFC);
          if ((tmp and $FFFF)<>$FFFF) and ((tmp shr 16)<>$FFFF) then
            _PCI Device: Vendor: (l and $FFFF)  Device: (l shr 16)_
        end;
      end;
    2:begin   {PCI type 2}
        outp($CF8,$80);
        outp($CFA,0);   {Bus select?}
        for i:=0 to 15 do
        begin
          tmp:=inpl(i*256 +$C000);
          if ((tmp and $FFFF)<>$FFFF) and ((tmp shr 16)<>$FFFF) then
            _PCI Device: Vendor: (l and $FFFF)  Device: (l shr 16)_
        end;
        outp($CF8,0);
      end;
  end;


The PCI BIOS interface requires a 386 or better CPU.


--------X-1AB001-----------------------------
INT 1A - ? PCI ? - INSTALLATION CHECK
        AX = B001h
Return: CF clear if installed
            DX = 4350h ('CP')
            CX = 2049h (' I')
--------X-1AB002-----------------------------
INT 1A - ? PCI ? - FIND PCI DEVICE
        AX = B002h
        CX = device ID
        DX = vendor ID
        SI = device index (0-n)
Return: CF clear if successful
                BH = bus number
                BL = device/function number (bits 7-3 device, bits 2-0 func)
--------X-1AB00A-----------------------------
INT 1A - ? PCI ? - READ CONFIGURATION DWORD
        AX = B00Ah
        BH = bus number
        BL = device/function number (bits 7-3 device, bits 2-0 function)
        DI = register number (0000h-00FFh)
Return: CF clear if successful
          CX = Low 16 bit of the DWORD
          DX = High 16 bit of the DWORD

--------X-1AB101-----------------------------
INT 1A - Intel PCI BIOS v2.0c - INSTALLATION CHECK
        AX = B101h
Return: AH = 00h if installed
            CF clear
            EDX = 20494350h (' ICP')
            EDI = physical address of protected-mode entry point (see #0528)
            AL = PCI hardware characteristics (see #0527)
            BH = PCI interface level major version (BCD)
            BL = PCI interface level minor version (BCD)
            CL = number of last PCI bus in system
        EAX, EBX, ECX, and EDX may be modified
        all other flags (except IF) may be modified
Note:   this function may require up to 1024 byte of stack; it will not enable
        interrupts if they were disabled before making the call

Bitfields for PCI hardware characteristics:
Bit(s)  Description (Table 0527)
 0      configuration space access mechanism 1 supported
 1      configuration space access mechanism 2 supported
 2-3    reserved
 4      Special Cycle generation mechanism 1 supported
 5      Special Cycle generation mechanism 2 supported
 6-7    reserved

(Table 0528)
Call protected-mode entry point with:
        registers as for real/V86-mode INT call
        CS = ring 0 descriptor with access to full address space
Return: as for real/V86-mode call
--------X-1AB102-----------------------------
INT 1A - Intel PCI BIOS v2.0c - FIND PCI DEVICE
        AX = B102h
        CX = device ID
        DX = vendor ID
        SI = device index (0-n)
Return: CF clear if successful
        CF set on error
        AH = status
            00h successful
                BH = bus number
                BL = device/function number (bits 7-3 device, bits 2-0 func)
            83h bad vendor ID
            86h device not found
        EAX, EBX, ECX, and EDX may be modified
        all other flags (except IF) may be modified
Notes:  this function may require up to 1024 byte of stack; it will not enable
        interrupts if they were disabled before making the call device ID FFFFh
        may be reserved as a wildcard in future implementations the meanings of
        BL and BH on return were exchanged between the initial drafts of the
        specification and final implementation all devices sharing a single
        vendor ID and device ID may be enumerated by incrementing SI from 0
        until error 86h is returned
--------X-1AB103-----------------------------
INT 1A - Intel PCI BIOS v2.0c - FIND PCI CLASS CODE
        AX = B103h
        ECX = class code (bits 23-0)
        SI = device index (0-n)
Return: CF clear if successful
        CF set on error
        AH = status
            00h successful
                BH = bus number
                BL = device/function number (bits 7-3 device, bits 2-0 func)
            86h device not found
        EAX, EBX, ECX, and EDX may be modified
        all other flags (except IF) may be modified
Notes:  this function may require up to 1024 byte of stack; it will not enable
        interrupts if they were disabled before making the call the meanings
        of BL and BH on return were exchanged between the initial drafts of
        the specification and final implementation all devices sharing the
        same Class Code may be enumerated by incrementing SI from 0 until
        error 86h is returned
--------X-1AB106-----------------------------
INT 1A - Intel PCI BIOS v2.0c - PCI BUS-SPECIFIC OPERATIONS
        AX = B106h
        BL = bus number
        EDX = Special Cycle data
Return: CF clear if successful
        CF set on error
        AH = status
            00h successful
            81h unsupported function
        EAX, EBX, ECX, and EDX may be modified
        all other flags (except IF) may be modified
Note:   this function may require up to 1024 byte of stack; it will not enable
        interrupts if they were disabled before making the call
--------X-1AB108-----------------------------
INT 1A - Intel PCI BIOS v2.0c - READ CONFIGURATION BYTE
        AX = B108h
        BL = device/function number (bits 7-3 device, bits 2-0 function)
        BH = bus number
        DI = register number (0000h-00FFh)
Return: CF clear if successful
             CL = byte read
        CF set on error
        AH = status
             00h successful
             87h bad register number
        EAX, EBX, ECX, and EDX may be modified
        all other flags (except IF) may be modified
Notes:  this function may require up to 1024 byte of stack; it will not enable
        interrupts if they were disabled before making the call the meanings
        of BL and BH on return were exchanged between the initial drafts of
        the specification and final implementation
--------X-1AB109-----------------------------
INT 1A - Intel PCI BIOS v2.0c - READ CONFIGURATION WORD
        AX = B109h
        BL = device/function number (bits 7-3 device, bits 2-0 function)
        BH = bus number
        DI = register number (0000h-00FFh)
Return: CF clear if successful
            CX = word read
        CF set on error
        AH = status
            00h successful
            87h bad register number
        EAX, EBX, ECX, and EDX may be modified
        all other flags (except IF) may be modified
Notes:  this function may require up to 1024 byte of stack; it will not enable
        interrupts if they were disabled before making the call the meanings
        of BL and BH on return were exchanged between the initial drafts of
        the specification and final implementation
--------X-1AB10A-----------------------------
INT 1A - Intel PCI BIOS v2.0c - READ CONFIGURATION DWORD
        AX = B10Ah
        BH = bus number
        BL = device/function number (bits 7-3 device, bits 2-0 function)
        DI = register number (0000h-00FFh)
Return: CF clear if successful
            ECX = dword read
        CF set on error
        AH = status
            00h successful
            87h bad register number
        EAX, EBX, ECX, and EDX may be modified
        all other flags (except IF) may be modified
Notes: this function may require up to 1024 byte of stack; it will not enable
       interrupts if they were disabled before making the call the meanings of
       BL and BH on return were exchanged between the initial drafts of the
       specification and final implementation
--------X-1AB10B-----------------------------
INT 1A - Intel PCI BIOS v2.0c - WRITE CONFIGURATION BYTE
        AX = B10Bh
        BH = bus number
        BL = device/function number (bits 7-3 device, bits 2-0 function)
        DI = register number (0000h-00FFh)
        CL = byte to write
Return: CF clear if successful
        CF set on error
        AH = status
            00h successful
            87h bad register number