Subversion Repositories Kolibri OS

;***************************************************************************

;

;  PCI CODE FOLLOWS

;

;  the following functions provide access to the PCI interface.

;  These functions are used by scan_bus, and also some ethernet drivers

;

;***************************************************************************

; PCI Bus defines

PCI_HEADER_TYPE             equ     0x0e  ;8 bit

PCI_BASE_ADDRESS_0          equ     0x10  ;32 bit

PCI_BASE_ADDRESS_5          equ     0x24  ;32 bits

PCI_BASE_ADDRESS_SPACE_IO   equ     0x01

PCI_VENDOR_ID               equ     0x00  ;16 bit

PCI_BASE_ADDRESS_IO_MASK    equ     0xFFFFFFFC

;***************************************************************************

;   Function

;      config_cmd

;

;   Description

;       creates a command dword  for use with the PCI bus

;       bus # in ebx

;      devfn in ecx

;       where in edx

;

;      command dword returned in eax

;       Only eax destroyed

;***************************************************************************

config_cmd:

    push    ecx

    mov     eax, ebx

    shl     eax, 16

    or      eax, 0x80000000

    shl     ecx, 8

    or      eax, ecx

    pop     ecx

    or      eax, edx

    and     eax, 0xFFFFFFFC

    ret

;***************************************************************************

;   Function

;      pcibios_read_config_byte

;

;   Description

;       reads a byte from the PCI config space

;       bus # in ebx

;      devfn in ecx

;       where in edx ( ls 16 bits significant )

;

;      byte returned in al ( rest of eax zero )

;       Only eax/edx destroyed

;***************************************************************************

pcibios_read_config_byte:

    call    config_cmd

    push    dx

    mov     dx, 0xCF8

    out     dx, eax

    pop     dx

    xor     eax, eax

    and     dx, 0x03

    add     dx, 0xCFC

;   and     dx, 0xFFC

    in      al, dx

    ret

;***************************************************************************

;   Function

;      pcibios_read_config_word

;

;   Description

;       reads a word from the PCI config space

;       bus # in ebx

;      devfn in ecx

;       where in edx ( ls 16 bits significant )

;

;      word returned in ax ( rest of eax zero )

;       Only eax/edx destroyed

;***************************************************************************

pcibios_read_config_word:

    call    config_cmd

    push    dx

    mov     dx, 0xCF8

    out     dx, eax

    pop     dx

    xor     eax, eax

    and     dx, 0x02

    add     dx, 0xCFC

;   and     dx, 0xFFC

    in      ax, dx

    ret

;***************************************************************************

;   Function

;      pcibios_read_config_dword

;

;   Description

;       reads a dword from the PCI config space

;       bus # in ebx

;      devfn in ecx

;       where in edx ( ls 16 bits significant )

;

;      dword returned in eax

;       Only eax/edx destroyed

;***************************************************************************

pcibios_read_config_dword:

    push    edx

    call    config_cmd

    push    dx

    mov     dx, 0xCF8

    out     dx, eax

    pop     dx

    xor     eax, eax

    mov     dx, 0xCFC

    in      eax, dx

    pop     edx

    ret

;***************************************************************************

;   Function

;      pcibios_write_config_byte

;

;   Description

;       write a byte in al to the PCI config space

;       bus # in ebx

;      devfn in ecx

;       where in edx ( ls 16 bits significant )

;

;       Only eax/edx destroyed

;***************************************************************************

pcibios_write_config_byte:

    push    ax

    call    config_cmd

    push    dx

    mov     dx, 0xCF8

    out     dx, eax

    pop     dx

    pop     ax

    and     dx, 0x03

    add     dx, 0xCFC

    out     dx, al

    ret

;***************************************************************************

;   Function

;      pcibios_write_config_word

;

;   Description

;       write a word in ax to the PCI config space

;       bus # in ebx

;      devfn in ecx

;       where in edx ( ls 16 bits significant )

;

;       Only eax/edx destroyed

;***************************************************************************

pcibios_write_config_word:

    push    ax

    call    config_cmd

    push    dx

    mov     dx, 0xCF8

    out     dx, eax

    pop     dx

    pop     ax

    and     dx, 0x02

    add     dx, 0xCFC

    out     dx, ax

    ret

;***************************************************************************

;   Function

;      delay_us

;

;   Description

;       delays for 30 to 60 us

;

;        I would prefer this routine to be able to delay for

;       a selectable number of microseconds, but this works for now.

;

;       If you know a better way to do 2us delay, pleae tell me!

;***************************************************************************

delay_us:

    push    eax

    push    ecx

    mov     ecx,2

    in      al,0x61

    and     al,0x10

    mov     ah,al

    cld

dcnt1:

    in      al,0x61

    and     al,0x10

    cmp     al,ah

    jz      dcnt1

    mov     ah,al

    loop    dcnt1

    pop     ecx

    pop     eax

    ret

;***************************************************************************

;   Function

;      scan_bus

;

;   Description

;       Scans the PCI bus for a supported device

;        If a supported device is found, the drvr_ variables are initialised

;       to that drivers functions ( as defined in the PCICards table)

;

;        io_addr   holds card I/O space. 32 bit, but only LS 16 bits valid

;        pci_data  holds the PCI vendor + device code

;       pci_dev   holds PCI bus dev #

;       pci_bus   holds PCI bus #

;

;        io_addr will be zero if no card found

;

;***************************************************************************

scan_bus:

    xor     eax, eax

    mov     [hdrtype], al

    mov     [pci_data], eax

    xor     ebx, ebx         ; ebx = bus# 0 .. 255

sb_bus_loop:

    xor     ecx, ecx         ; ecx = devfn# 0 .. 254  ( not 255? )

sb_devf_loop:

    mov     eax, ecx

    and     eax, 0x07

    cmp     eax, 0

    jne     sb_001

    mov     edx, PCI_HEADER_TYPE

    call    pcibios_read_config_byte

    mov     [hdrtype], al

    jmp     sb_002

sb_001:

    mov     al, [hdrtype]

    and     al, 0x80

    cmp     al, 0x80

    jne     sb_inc_devf

sb_002:

    mov     edx, PCI_VENDOR_ID

    call    pcibios_read_config_dword

    mov     [vendor_device], eax

    cmp     eax, 0xffffffff

    je      sb_empty

    cmp     eax, 0

    jne     sb_check_vendor

sb_empty:

    mov     [hdrtype], byte 0

    jmp     sb_inc_devf

sb_check_vendor:

    ; iterate though PCICards until end or match found

    mov     esi, PCICards

sb_check:

    cmp     [esi], dword 0

    je      sb_inc_devf                ; Quit if at last entry

    cmp     eax, [esi]

    je      sb_got_card

    add     esi, PCICARDS_ENTRY_SIZE

    jmp     sb_check

sb_got_card:

    ; indicate that we have found the card

    mov     [pci_data], eax

    mov     [pci_dev], ecx

    mov     [pci_bus], ebx

    ; Define the driver functions

    push    eax

    mov     eax, [esi+4]

    mov     [drvr_probe], eax

    mov     eax, [esi+8]

    mov     [drvr_reset], eax

    mov     eax, [esi+12]

    mov     [drvr_poll], eax

    mov     eax, [esi+16]

    mov     [drvr_transmit], eax

    pop     eax

    mov     edx, PCI_BASE_ADDRESS_0

sb_reg_check:

    call    pcibios_read_config_dword

    mov     [io_addr], eax

    and     eax, PCI_BASE_ADDRESS_IO_MASK

    cmp     eax, 0

    je      sb_inc_reg

    mov     eax, [io_addr]

    and     eax, PCI_BASE_ADDRESS_SPACE_IO

    cmp     eax, 0

    je      sb_inc_reg

    mov     eax, [io_addr]

    and     eax, PCI_BASE_ADDRESS_IO_MASK

    mov     [io_addr], eax

sb_exit1:

    ret

sb_inc_reg:

    add     edx, 4

    cmp     edx, PCI_BASE_ADDRESS_5

    jbe     sb_reg_check

sb_inc_devf:

    inc     ecx

    cmp     ecx, 255

    jb      sb_devf_loop

    inc     ebx

    cmp     ebx, 256

    jb      sb_bus_loop

    ; We get here if we didn't find our card

    ; set io_addr to 0 as an indication

    xor     eax, eax

    mov     [io_addr], eax

sb_exit2:

    ret