Chip 1994 February/CHIP0294.ISO/digital/magazin/trumpet/pktdrvs/isolan.asm

Assembly Source File | 1993-06-11 | 14.3 KB | 657 lines

version    equ    2

    include    defs.asm    ;SEE ENCLOSED COPYRIGHT MESSAGE

; Packet driver for BICC Data Networks' ISOLAN 4110 ethernet
; controller, written by
;    Rainer Toebbicke
;    European Organisation of Nuclear Research (CERN)
;    Geneva, Switzerland
; based on the "generic" packet driver by Russell Nelson.



; BICC ISOLAN card constants

IS_SAP    struc            ;Service Access Point channel
IS_S_Data    db    ?    ;data semaphore
IS_S_Taken    db    ?    ;taken semaphore
        dw    ?

IS_S_Event    db    ?

IS_S_SrcEaddr    db    6 dup(?)    ;source Ethernet address
IS_S_SrcLsap    db    ?
IS_S_DstEaddr    db    6 dup(?)
IS_S_DstLsap    db    ?
        db    ?
IS_S_Status    dw    ?
        db    ?
IS_S_SDUptr    dw    ?
IS_SAP        ends

; Bits defined in IS_S_Event
IS_M_Init    equ    0ch
IS_M_DataRq    equ    09h
IS_M_DataInd    equ    0ah
IS_Board_Init    equ    0dh


IS        segment    at 0
        org    8000h
IS_Sign        db    ?        ;test for card presence
IS_Reset    db    ?
IS_Diagok    db    ?
IS_Error    db    ?
IS_ErrCode    db    ?
        org    800eh
IS_PgmStart    dw    ?

IS_IER        db    ?        ;interrupt enable register
IS_I_Tx        equ    01h        ;transmit interrupt
IS_I_Rx        equ    02h        ;receive interrupt

IS_ISR        db    ?        ;interrupt status reg
        org    8014h
IS_BlueBook    db    ?
IS_LLC1        db    ?
IS_Precv    db    ?        ;promiscuous receive flag
IS_LanceRev    db    ?
IS_MacReflSup    db    ?        ;MAC reflection suppression
        org    8020h
IS_Xmit        IS_SAP    <>        ;Transmit channel
        org    8040h
IS_Rcv        IS_SAP    <>        ;Receive channel
        org    8060h
IS_Eaddr    db    6 dup(?)    ;This card's Ethernet address

IS        ends


IS_SDU        struc
IS_SDU_DataOff    db    ?        ;offset to data
IS_SDU_L    dw    ?        ;length of packet
IS_SDU        ends


ENET_HDR    equ    EADDR_LEN*2+2    ;length of ethernet header



code    segment    word public
    assume    cs:code, ds:code

    public    int_no,    MemBase
int_no    db    2,0,0,0            ;must be four bytes long for get_number.
MemBase    dw    0b800h,0

    public    driver_class, driver_type, driver_name, driver_function, parameter_list
driver_class    db    BLUEBOOK, IEEE8023, 0        ;from the packet spec
driver_type    db    4+128        ;from the packet spec
driver_name    db    'ISOLAN',0    ;name of the driver.
driver_function    db    2
parameter_list    label    byte
    db    1    ;major rev of packet driver
    db    9    ;minor rev of packet driver
    db    14    ;length of parameter list
    db    EADDR_LEN    ;length of MAC-layer address
    dw    GIANT    ;MTU, including MAC headers
    dw    MAX_MULTICAST * EADDR_LEN    ;buffer size of multicast addrs
    dw    0    ;(# of back-to-back MTU rcvs) - 1
    dw    0    ;(# of successive xmits) - 1
int_num    dw    0    ;Interrupt # to hook for post-EOI
            ;processing, 0 == none,

    public    rcv_modes
rcv_modes    dw    4        ;number of receive modes in our table.
        dw    0,0,0,rcv_mode_3

    include    movemem.asm
    include    timeout.asm

    public bad_command_intercept
bad_command_intercept:
;called with ah=command, unknown to the skeleton.
;exit with nc if okay, cy, dh=error if not.
    mov    dh,BAD_COMMAND
    stc
    ret

    public    as_send_pkt
; The Asynchronous Transmit Packet routine.
; Enter with es:di -> i/o control block, ds:si -> packet, cx = packet length,
;   interrupts possibly enabled.
; Exit with nc if ok, or else cy if error, dh set to error number.
;   es:di and interrupt enable flag preserved on exit.
as_send_pkt:
    ret

    public    drop_pkt
; Drop a packet from the queue.
; Enter with es:di -> iocb.
drop_pkt:
    assume    ds:nothing
    ret

    public    xmit
; Process a transmit interrupt with the least possible latency to achieve
;   back-to-back packet transmissions.
; May only use ax and dx.
xmit:
    assume    ds:nothing
    ret


    public    send_pkt
send_pkt:
;enter with es:di->upcall routine, (0:0) if no upcall is desired.
;  (only if the high-performance bit is set in driver_function)
;enter with ds:si -> packet, cx = packet length.
;exit with nc if ok, or else cy if error, dh set to error number.
    assume    ds:nothing

    cmp    cx,GIANT        ; Is this packet too large?
    ja    send_pkt_toobig

    cld                ;moves go forward
    mov    ax,MemBase
    mov    es,ax            ;address the card
    assume    es:IS
    push    cx            ;save length

; Wait for the transmit channel to become free
    mov    cx,10            ;wait 10 36ths of a second.
    call    set_timeout
tx_wait:
    test    IS_Xmit.IS_S_Data,0ffh
    jnz    tx_idle
    call    do_timeout
    jnz    tx_wait
    pop    cx            ;remove from stack
    mov    dh,CANT_SEND        ;transmit error
    stc
    ret

send_pkt_toobig:
    mov    dh,NO_SPACE
    stc
    ret

tx_idle:
    mov    IS_Xmit.IS_S_Data,0        ;our channel now
    mov    IS_Xmit.IS_S_Event,IS_M_DataRq    ;sending Data

; copy destination ethernet addr
    mov    cx,EADDR_LEN/2
    lea    di,IS_Xmit.IS_S_DstEaddr
    rep    movsw

; copy source ethernet addr
    mov    cx,EADDR_LEN/2
    lea    di,IS_Xmit.IS_S_SrcEaddr
    rep    movsw

; copy type field
    lodsw
    xchg    ah,al                ;8086 order
    mov    IS_Xmit.IS_S_Status,ax

    pop    cx                ;restore count
    sub    cx,ENET_HDR            ;minus header

    mov    di,IS_Xmit.IS_S_SDUptr        ;point to SDU
    mov    es:IS_SDU_L[di],cx        ;set count
    xor    ah,ah
    mov    al,es:IS_SDU_DataOff[di]
    add    di,ax                ;point to data

    call    movemem                ; now copy the buffer

    mov    IS_Xmit.IS_S_Taken,1        ;release channel
    clc                    ;no error occurred
    ret
    assume    es:nothing


    public    set_address
set_address:
;enter with ds:si -> Ethernet address, CX = length of address.
;exit with nc if okay, or cy, dh=error if any errors.
    assume    ds:nothing
    cmp    cx,EADDR_LEN
    jnb    set_addr_ok        ;buffer ok
    mov    dh,BAD_ADDRESS
    stc
    ret

set_addr_ok:
    push    es
    push    di
    mov    ax,MemBase        ;point to interface
    mov    es,ax
    assume    es:IS

    mov    di,offset IS_Eaddr    ;point to our E-net addr
    mov    cx,EADDR_LEN/2
    rep    movsw

; reset the board's software, don't really know if this is needed
    mov    IS_Xmit.IS_S_Data,0        ;our channel now
    mov    IS_Xmit.IS_S_Event,IS_Board_Init ;reboot
    mov    IS_Xmit.IS_S_Taken,1        ;issue the command

; wait for request to complete
    mov    cx,10            ;wait 10 36ths of a second.
    call    set_timeout
set_wait_2:
    test    IS_Xmit.IS_S_Data,0ffh
    jnz    set_done
    call    do_timeout
    jnz    set_wait_2

set_done:
    mov    cx,EADDR_LEN        ;return their address length.
    pop    di
    pop    es
    assume    es:nothing
    clc
    ret



rcv_mode_3:
;receive mode 3 is the only one we support, so we don't have to do anything.
    ret


    public    set_multicast_list
set_multicast_list:
;enter with ds:si ->list of multicast addresses, ax = number of addresses,
;  cx = number of bytes.
;return nc if we set all of them, or cy,dh=error if we didn't.
    mov    dh,NO_MULTICAST
    stc
    ret


    public    terminate
terminate:
    ret

    public    reset_interface
reset_interface:
;reset the interface.
    assume    ds:code
    push    ds
    mov    ax,MemBase
    mov    ds,ax
    assume    ds:IS
    mov    IS_IER,0
    pop    ds
    ret


;called when we want to determine what to do with a received packet.
;enter with cx = packet length, es:di -> packet type, dl = packet class.
    extrn    recv_find: near

;called after we have copied the packet into the buffer.
;enter with ds:si ->the packet, cx = length of the packet.
    extrn    recv_copy: near

;call this routine to schedule a subroutine that gets run after the
;recv_isr.  This is done by stuffing routine's address in place
;of the recv_isr iret's address.  This routine should push the flags when it
;is entered, and should jump to recv_exiting_exit to leave.
;enter with ax = address of routine to run.
    extrn    schedule_exiting: near

;recv_exiting jumps here to exit, after pushing the flags.
    extrn    recv_exiting_exit: near

    extrn    count_in_err: near
    extrn    count_out_err: near

    public    recv
recv:
;called from the recv isr.  All registers have been saved, and ds=cs.
;Upon exit, the interrupt will be acknowledged.
    assume    ds:code
    mov    ax,MemBase
    mov    ds,ax
    assume    ds:IS

    mov    al,IS_ISR        ;get interrupt status
    test    al,IS_I_RX        ;receive interrupt?
    jnz    rcv_test_errors        ;yes...
    jmp    rcv_done

rcv_test_errors:

; some thorough testing missing here
; anyway, don't know what to test


rcv_no_errors:
    mov    IS_Rcv.IS_S_Data,0    ;block channel
    mov    di,IS_Rcv.IS_S_SDUptr    ;point to SDU
    mov    cx,IS_SDU_L[di]        ;get length
    add    cx,ENET_HDR        ;plus ethernet header


; These following lines correctly point to the type field.
; Addressability to the whole buffer on the 'receiver' call
; would be lost, a feature useful to some applications

;    mov     ax,IS_Rcv.IS_S_Status ;get type field
;    xchg    ah,al         ;in network byte order
;    push    ax         ;have to place it somewhere
;    mov    di,sp
;    push    ss
;    pop    es            ;es:di at type field

; The following 'hack' keeps addressability to the packet
; on the 'receiver' call but stays compatible with the
; packet driver skeleton.
; This feature is indicated by a bit in the type number (ugly)
; which the application can examine

    mov    al,IS_SDU_DataOff[di]    ;offset to to data
    sub    al,2            ;offset to type field
    cbw
    add    di,ax            ;point to type field
    movseg    es,ds

    movseg    ds,cs
    assume    ds:code

    mov    dl, BLUEBOOK        ;assume bluebook Ethernet.
    mov    ax, es:[di]
    xchg    ah, al
    cmp     ax, 1500
    ja    BlueBookPacket
    inc    di            ;set di to 802.2 header
    inc    di
    mov    dl, IEEE8023
BlueBookPacket:
    call    recv_find        ;do we want this packet?
;    add    sp,2               ;remove type field

    mov    ax,es
    or    ax,di
    jz    rcv_done_0        ;pointer zero, give up

    push    es
    push    di            ;save pointer

    mov    ax,MemBase
    mov    ds,ax
    assume    ds:IS

; set up ethernet header
    mov    cx,EADDR_LEN/2
    mov    si,offset IS_Rcv.IS_S_DstEaddr
    rep    movsw
    mov    cx,EADDR_LEN/2
    mov    si,offset IS_Rcv.IS_S_SrcEaddr
    rep    movsw
    mov    ax,IS_Rcv.IS_S_Status        ;type field
    xchg    ah,al                ;in network byte order
    stosw

    mov    si,IS_Rcv.IS_S_SDUptr        ;point to SDU
    mov    cx,IS_SDU_L[si]            ;get length
    push    cx                ;save for later
    mov    al,IS_SDU_DataOff[si]
    xor    ah,ah
    add    si,ax                ;point to data

    call    movemem

    pop    cx            ;restore count
    pop    si            ;restore pointer
    pop    ds            ;restore pointer
    assume    ds:nothing

    add    cx,ENET_HDR        ;adjust length
    call    recv_copy        ;wake up client

rcv_done_0:
    mov    ax,MemBase        ;point to interface
    mov    ds,ax
    assume    ds:IS

rcv_done:
    mov    IS_Rcv.IS_S_Taken,1    ;release channel
    mov    IS_ISR,0        ;clear interrupt
    movseg    ds,cs
    assume    ds:code
    ret


    public    timer_isr
timer_isr:
;if the first instruction is an iret, then the timer is not hooked
    iret

;any code after this will not be kept after initialization. Buffers
;used by the program, if any, are allocated from the memory between
;end_resident and end_free_mem.
    public end_resident,end_free_mem
end_resident    label    byte
end_free_mem    label    byte


    public    usage_msg
usage_msg db "usage: ISOLAN [options] <packet_int_no> <int_level>    <mem_addr>",CR,LF,'$'

    public    copyright_msg
copyright_msg    db    "Packet    driver for BICC    ISOLAN device, version ",'0'+(majver / 10),'0'+(majver mod 10),".",'0'+version,CR,LF
        db    "Portions Copyright 1989, R.Toebbicke, CERN, Switzerland",CR,LF
        db    '$'

errmsg1    db    "No BICC Isolan    board found at this address.",CR,LF,'$'
diag_errmsg    db    "Error - ISOLAN    Diagnostics failed.",CR,LF,'$'

diag_start_msg    db    "ISOLAN    Diagnostics running... $"
diag_end_msg    db    " done.",CR,LF,'$'

int_no_name    db    "Interrupt number $"
MemBaseName    db    "Shared    Memory address $"
MemPrt    dw    0c000h,0



    extrn    set_recv_isr: near

;enter with si -> argument string, di -> word to store.
;if there is no number, don't change the number.
    extrn    get_number: near

;enter with dx -> name of word, di -> dword to print.
    extrn    print_number: near

;-> the assigned Ethernet address of the card.
    extrn    rom_address: byte

    public    parse_args
parse_args:
;exit with nc if all went well, cy otherwise.
    mov    di,offset int_no
    call    get_number
    mov    di,offset MemPrt
    call    get_number
    mov    di,MemPrt
    sub    di,800h            ;BICC standard notation
    mov    MemBase,di
    clc
    ret


bad_board:
    mov    dx,offset errmsg1
    assume    ds:nothing
    movseg    ds,cs
    stc
    ret


    public    etopen
etopen:
    mov    ax,MemBase
    mov    ds,ax
    assume    ds:IS

; test if board exists
    mov    IS_Sign,42
    cmp    IS_Sign,42
    jne    bad_board

    mov    IS_Sign,0ffh-42
    cmp    IS_Sign,0ffh-42
    jne    bad_board

    cmp    IS_Reset,01h        ;already running?
    jne    diag_not_ok
    jmp    diag_ok            ;yes, let it run
diag_not_ok:

    mov    IS_Reset,0
    mov    cx,10            ;wait 10 36ths of a second.
    call    set_timeout
diag_w_0:
    cmp    IS_Reset,0fah
    je    diag_1
    call    do_timeout
    jne    diag_w_0

diag_1:
    mov    IS_Reset,0ffh
    mov    cx,10            ;wait 10 36ths of a second.
    call    set_timeout
diag_w_1:
    cmp    IS_Reset,0fah
    je    diag_2
    call    do_timeout
    jne    diag_w_1

diag_2:
    mov    IS_Reset,0e5h
    mov    cx,10            ;wait 10 36ths of a second.
    call    set_timeout
diag_w_2:
    cmp    IS_Reset,0fah
    je    diag_3
    call    do_timeout
    jne    diag_w_2

diag_3:
    mov    IS_Reset,09dh        ;start diagnostics

    push    ds
    push    cs
    pop    ds
    mov    dx,offset diag_start_msg
    mov    ah,9
    int    21h
    pop    ds

    mov    bx,72            ;double loop, takes some time
diag_w_3_0:
    mov    cx,10            ;wait 10 36ths of a second.
    call    set_timeout
diag_w_3:
    cmp    IS_Diagok,01h
    je    diag_4
    call    do_timeout
    jne    diag_w_3
    dec    bx
    jnz    diag_w_3_0
    mov    dx,offset diag_errmsg
    stc
    ret

diag_4:
    push    ds
    push    cs
    pop    ds
    mov    dx,offset diag_end_msg
    mov    ah,9
    int    21h
    pop    ds

    mov    ax,0800h
    mov    IS_PgmStart,ax
    mov    IS_Reset,01h        ;run the program


; enable the board's interrupts
diag_ok:

; get the board's Ethernet address.
      push    cs
    pop    es
    mov    si,offset IS_Eaddr    ;point to our E-net addr
    mov    di,offset rom_address
    mov    cx,EADDR_LEN/2
    rep    movsw

; enable the board's interrupts
    push    ds
    mov    ax,cs
    mov    ds,ax            ;set ds=cs
    call    set_recv_isr
    pop    ds

    mov    IS_BlueBook,1        ;enable Blue Book MAC
    mov    IS_LLC1,1        ;disable LLC1 service
    mov    IS_MacReflSup,1        ;suppress MAC reflection
    mov    IS_IER,IS_I_RX        ;enable for receive
    mov    IS_ISR,0        ;clear previous

; reset the board's software, just in case...
    mov    IS_Xmit.IS_S_Data,0        ;our channel now
    mov    IS_Xmit.IS_S_Event,IS_Board_Init ;init MAC layer
    mov    IS_Xmit.IS_S_Taken,1        ;issue the command

; again wait for request to complete
    mov    cx,10            ;wait 10 36ths of a second.
    call    set_timeout
in_wait_2:
    test    IS_Xmit.IS_S_Data,0ffh
    jnz    in_done
    call    do_timeout
    jne    in_wait_2

in_done:

    mov    al, int_no        ; Get board's interrupt vector
    add    al, 8
    cmp    al, 8+8            ; Is it a slave 8259 interrupt?
    jb    set_int_num        ; No.
    add    al, 70h - 8 - 8        ; Map it to the real interrupt.
set_int_num:
    xor    ah, ah            ; Clear high byte
    mov    int_num, ax        ; Set parameter_list int num.

;if all is okay,
    movseg    ds,cs
    clc
    ret

    public    print_parameters
print_parameters:
;echo our command-line parameters
    mov    di,offset int_no
    mov    dx,offset int_no_name
    call    print_number
    mov    di,offset MemPrt
    mov    dx,offset MemBaseName
    call    print_number
    ret


code    ends

    end