Chip 1994 February/CHIP0294.ISO/digital/magazin/trumpet/pktdrvs/3c501.asm

Assembly Source File | 1993-10-08 | 15.4 KB | 685 lines

version    equ    2

    include    defs.asm

;Ported from Phil Karn's ec.c, a C-language driver for the 3COM 3C501
;by Russell Nelson.  Any bugs are due to Russell Nelson.
;*  Updated to version 1.08 Feb. 17, 1989.

;  Copyright, 1988-1992, Russell Nelson, Crynwr Software

;   This program is free software; you can redistribute it and/or modify
;   it under the terms of the GNU General Public License as published by
;   the Free Software Foundation, version 1.
;
;   This program is distributed in the hope that it will be useful,
;   but WITHOUT ANY WARRANTY; without even the implied warranty of
;   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;   GNU General Public License for more details.
;
;   You should have received a copy of the GNU General Public License
;   along with this program; if not, write to the Free Software
;   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

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

;The various IE command registers
EDLC_ADDR    equ    00h    ;EDLC station address, 6 bytes
EDLC_RCV    equ    06h    ;EDLC receive csr
EDLC_XMT    equ    07h    ;EDLC transmit csr
IE_GP        equ    08h    ;GP pointer
IE_RP        equ    0ah    ;Receive buffer pointer
IE_SAPROM    equ    0ch    ;window on station addr prom
IE_CSR        equ    0eh    ;IE command/status
IE_BFR        equ    0fh    ;window on packet buffer

;Bits in EDLC_RCV, interrupt enable on write, status when read
EDLC_NONE    equ    000h    ;match mode in bits 5-6, write only
EDLC_ALL    equ    040h    ;promiscuous receive, write only
EDLC_BROAD    equ    080h    ;station address plus broadcast
EDLC_MULTI    equ    0c0h    ;station address plus multicast

EDLC_STALE    equ    80h    ;receive CSR status previously read
EDLC_GOOD    equ    20h    ;well formed packets only
EDLC_ANY    equ    10h    ;any packet, even those with errors
EDLC_SHORT    equ    08h    ;short frame
EDLC_DRIBBLE    equ    04h    ;dribble error
EDLC_FCS    equ    02h    ;CRC error
EDLC_OVER    equ    01h    ;data overflow

EDLC_RERROR    equ    EDLC_SHORT or EDLC_DRIBBLE or EDLC_FCS or EDLC_OVER
EDLC_RMASK    equ    EDLC_GOOD or EDLC_ANY or EDLC_RERROR

;bits in EDLC_XMT, interrupt enable on write, status when read
EDLC_IDLE    equ    08h    ;transmit idle
EDLC_16        equ    04h    ;packet experienced 16 collisions
EDLC_JAM    equ    02h    ;packet experienced a collision
EDLC_UNDER    equ    01h    ;data underflow

;bits in IE_CSR
IE_RESET    equ    80h    ;reset the controller (wo)
IE_XMTBSY    equ    80h    ;Transmitter busy (ro)
IE_RIDE        equ    40h    ;request interrupt/DMA enable (rw)
IE_DMA        equ    20h    ;DMA request (rw)
IE_EDMA        equ    10h    ;DMA done (ro)

IE_BUFCTL    equ    0ch    ;mask for buffer control field (rw)
IE_LOOP        equ    0ch    ;2 bit field in bits 2,3, loopback
IE_RCVEDLC    equ    08h    ;gives buffer to receiver
IE_XMTEDLC    equ    04h    ;gives buffer to transmit
IE_SYSBFR    equ    00h    ;gives buffer to processor

IE_CRC        equ    01h    ;causes CRC error on transmit (wo)
IE_RCVBSY    equ    01h    ;receive in progress (ro)

BFRSIZ        equ    2048    ;number of bytes in a buffer

    public    int_no
int_no        db    3,0,0,0        ; interrupt number.
io_addr        dw    0300h,0        ; I/O address for card (jumpers)

    public    driver_class, driver_type, driver_name, driver_function, parameter_list
driver_class    db    BLUEBOOK, IEEE8023, 0        ;from the packet spec
driver_type    db    1        ;from the packet spec
driver_name    db    '3C501',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    7        ;number of receive modes in our table.
        dw    0               ;There is no mode zero
        dw    rcv_mode_1
        dw    0        ;don't want to bother.
        dw    rcv_mode_3
        dw    0        ;haven't set up perfect filtering yet.
        dw    rcv_mode_5
        dw    rcv_mode_6

ipkt_size    dw    ?
opkt_size    dw    ?

    extrn    is_186: byte        ;=0 if 808[68], =1 if 80[123]86.
our_type    dw    ?,?

    include    io8.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

    cmp    cx,RUNT        ; minimum length for Ether
    jae    oklen
    mov    cx,RUNT        ; make sure size at least RUNT
oklen:
    inc    cx            ;round size up to next even number.
    and    cx,not 1

;Wait for transmitter ready, if necessary. IE_XMTBSY is valid
;only in the transmit mode, hence the initial check.

    loadport
    setport    IE_CSR
    in    al,dx
    and    al,IE_BUFCTL
    cmp    al,IE_XMTEDLC
    jne    send_pkt_2

    mov    bx,20000        ;try this many times.
send_pkt_3:
    in    al,dx            ;if not busy, exit.
    and    al,IE_XMTBSY
    je    send_pkt_2
    dec    bx
    jne    send_pkt_3
    mov    dh,CANT_SEND        ;timed out, can't send.
    stc
    ret
send_pkt_toobig:
    mov    dh,NO_SPACE
    stc
    ret
send_pkt_2:

;Get control of the board buffer and disable receiver
    mov    al,IE_RIDE or IE_SYSBFR
    setport    IE_CSR
    out    dx,al

;Point GP at beginning of packet
    mov    ax,BFRSIZ
    sub    ax,cx
    setport    IE_GP
    out    dx,ax

    setport    IE_BFR

    mov    opkt_size,cx    ; opkt_size = cx;
    call    repoutsb

;Start transmitter
;Point GP at beginning of packet
    mov    ax,BFRSIZ
    sub    ax,opkt_size
    setport    IE_GP
    out    dx,ax

    mov    al,IE_RIDE or IE_XMTEDLC
    setport    IE_CSR
    out    dx,al

  if 1
    mov    bx,20000        ;try this many times.
send_pkt_4:
    in    al,dx            ;if not busy, exit.
    and    al,IE_XMTBSY
    je    send_pkt_5
    dec    bx
    jne    send_pkt_4
    mov    dh,CANT_SEND        ;timed out, can't send.
    stc
    ret
send_pkt_5:

  endif

    clc
    ret


;Set Ethernet address on controller
    public    set_address
set_address:
    assume    ds:nothing
;enter with ds:si -> Ethernet address, CX = length of address.
;exit with nc if okay, or cy, dh=error if any errors.
;
    cmp    cx,EADDR_LEN        ;ensure that their address is okay.
    je    set_address_4
    mov    dh,BAD_ADDRESS
    stc
    jmp    short set_address_done
set_address_4:

    loadport
    setport    EDLC_ADDR
set_address_1:
    lodsb
    out    dx,al
    inc    dx
    loop    set_address_1
set_address_okay:
    mov    cx,EADDR_LEN        ;return their address length.
    clc
set_address_done:
    movseg    ds,cs
    assume    ds:code
    ret


rcv_mode_1:
;Set up the receiver interrupts and flush status
    mov    al,EDLC_NONE
    loadport
    setport    EDLC_RCV
    out    dx,al
    in    al,dx            ;flush status.

    ret


rcv_mode_3:
;Set up the receiver interrupts and flush status
    mov    al,EDLC_BROAD or EDLC_GOOD or EDLC_ANY or EDLC_SHORT or EDLC_DRIBBLE or EDLC_FCS or EDLC_OVER
    loadport
    setport    EDLC_RCV
    out    dx,al
    in    al,dx            ;flush status.

    ret


rcv_mode_5:
;Set up the receiver interrupts and flush status
    mov    al,EDLC_MULTI or EDLC_GOOD or EDLC_ANY or EDLC_SHORT or EDLC_DRIBBLE or EDLC_FCS or EDLC_OVER
    loadport
    setport    EDLC_RCV
    out    dx,al
    in    al,dx            ;flush status.

    ret


rcv_mode_6:
;Set up the receiver interrupts and flush status
    mov    al,EDLC_ALL or EDLC_GOOD or EDLC_ANY or EDLC_SHORT or EDLC_DRIBBLE or EDLC_FCS or EDLC_OVER
    loadport
    setport    EDLC_RCV
    out    dx,al
    in    al,dx            ;flush status.

    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:
;Pulse IE_RESET
    mov    al,IE_RESET
    loadport
    setport    IE_CSR
    out    dx,al
    mov    al,0
    out    dx,al

    ret

    public    reset_interface
reset_interface:
;reset the interface.
;we don't do anything.
    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

;Check for transmit jam

    loadport
    setport    IE_CSR
    in    al,dx
    and    al,IE_XMTBSY
    jne    recv_isr_1

    setport    EDLC_XMT
    in    al,dx
    test    al,EDLC_16
    je    recv_isr_2
;ecp->estats.jam16++;
    call    rcv_fixup
    jmp    short     recv_isr_3
recv_isr_2:
    test    al,EDLC_JAM
    je    recv_isr_3
;Crank counter back to beginning and restart transmit
;ecp->estats.jam++;
    mov    al,IE_RIDE or IE_SYSBFR
    setport    IE_CSR
    out    dx,al

    mov    ax,BFRSIZ
    sub    ax,opkt_size
    setport    IE_GP
    out    dx,ax

    mov    al,IE_RIDE or IE_XMTEDLC
    setport    IE_CSR
    out    dx,al

recv_isr_3:

recv_isr_1:
    loadport
    setport    EDLC_RCV
    in    al,dx
    test    al,EDLC_STALE
    jne    recv_isr_4_j_1
    test    al,EDLC_OVER
    je    recv_isr_5
;ecp->estats.over++;
    call    rcv_fixup
    jmp    recv_isr_1
recv_isr_5:
    test    al,EDLC_SHORT or EDLC_FCS or EDLC_DRIBBLE
    je    recv_isr_6
;ecp->estats.bad++;
    call    rcv_fixup
    jmp    recv_isr_1
recv_isr_4_j_1:
    jmp    recv_isr_4
recv_isr_6:
    test    al,EDLC_ANY
    je    recv_isr_4_j_1
;Get control of the buffer
    mov    al,IE_RIDE or IE_SYSBFR
    setport    IE_CSR
    out    dx,al

    setport    IE_RP
    in    ax,dx            ;get the size.
    mov    ipkt_size,ax
    cmp    ax,RUNT            ;less than RUNT?
    jb    recv_isr_7        ;yes.
    cmp    ax,GIANT        ;greater than GIANT?
    jbe    recv_isr_8        ;no.
recv_isr_7:
    call    count_in_err
;ecp->estats.bad++;
    jmp    recv_isr_9
recv_isr_8:
;Put it on the receive queue

    mov    ax,EADDR_LEN+EADDR_LEN    ;seek to the type word.
    setport    IE_GP
    out    dx,ax

    setport    IE_BFR
    in    al,dx            ;read the type word out of the board.
    mov    ah,al
    in    al,dx
    xchg    al,ah            ;should be in network byte order.
    mov    our_type,ax
    in    al,dx            ;read the type word out of the board.
    mov    ah,al
    in    al,dx
    xchg    al,ah            ;should be in network byte order.
    mov    our_type+2,ax

    movseg    es,ds            ;look up our type.
    mov    di,offset our_type

    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:

    mov    cx,ipkt_size
    call    recv_find

    mov    ax,es            ;is this pointer null?
    or    ax,di
    je    recv_isr_9        ;yes - just free the frame.

    push    es            ;remember where the buffer pointer is.
    push    di

    xor    ax,ax            ;seek to the beginning again.
    loadport
    setport    IE_GP
    out    dx,ax

    mov    cx,ipkt_size
    setport    IE_BFR

    call    repinsb

    pop    si
    pop    ds
    assume    ds:nothing
    mov    cx,ipkt_size
    call    recv_copy        ;tell them that we copied it.

    movseg    ds,cs
    assume    ds:code

recv_isr_9:
    mov    al,IE_RIDE or IE_RCVEDLC
    loadport
    setport    IE_CSR
    out    dx,al
    xor    al,al
    setport    IE_RP
    out    dx,al
recv_isr_4:
;Clear any spurious interrupts
    loadport
    setport    EDLC_RCV
    in    al,dx

    setport    EDLC_XMT
    in    al,dx

    ret


rcv_fixup:
    call    count_out_err

    mov    al,IE_RIDE or IE_SYSBFR
    loadport
    setport    IE_CSR
    out    dx,al

    mov    al,IE_RIDE or IE_RCVEDLC
    setport    IE_CSR
    out    dx,al

    mov    al,0
    setport    IE_RP
    out    dx,al

    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.  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: 3C501 [options] <packet_int_no> <hardware_irq> <io_addr>",CR,LF,'$'

    public    copyright_msg
copyright_msg    db    "Packet driver for the 3COM 3C501, version ",'0'+(majver / 10),'0'+(majver mod 10),".",'0'+version,CR,LF
        db    "Portions Copyright 1988 Phil Karn",CR,LF,'$'

no_3c501_msg    db    "No 3C501 found at that address.",CR,LF,'$'
ether_bdcst    db    6 dup(-1)    ;ethernet broadcast address.

int_no_name    db    "Interrupt number ",'$'
io_addr_name    db    "I/O port ",'$'

    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 io_addr
    call    get_number
    clc
    ret


    public    etopen
etopen:
;  Initialize the Ethernet board, set receive type.
;
;  check for correct EPROM location
;
;Pulse IE_RESET
    mov    al,IE_RESET
    loadport
    setport    IE_CSR
    out    dx,al

    call    set_recv_isr

    movseg    es,ds
    mov    di,offset rom_address
    mov    cx,EADDR_LEN
    xor    bx,bx
get_address_1:
    mov    ax,bx
    loadport
    setport    IE_GP
    out    dx,ax

    setport    IE_SAPROM
    in    al,dx
    stosb
    inc    bx
    loop    get_address_1

;See if there really is a 3c501 there.
    mov    cx,EADDR_LEN
    mov    si,offset rom_address
    mov    di,offset ether_bdcst
    repe    cmpsb
    jne    have_3c501        ;not broadcast address -- must be real.
    mov    dx,offset no_3c501_msg
    stc
    ret
have_3c501:

    mov    si,offset rom_address
    mov    cx,EADDR_LEN
    call    set_address

;Enable DMA/interrupt request, gain control of buffer
    mov    al,IE_RIDE or IE_SYSBFR
    loadport
    setport    IE_CSR
    out    dx,al

;Enable transmit interrupts
    mov    al,EDLC_16 or EDLC_JAM
    setport    EDLC_XMT
    out    dx,al

;Set up the receiver interrupts and flush status
    mov    al,EDLC_MULTI or EDLC_GOOD or EDLC_ANY or EDLC_SHORT or EDLC_DRIBBLE or EDLC_FCS or EDLC_OVER
    setport    EDLC_RCV
    out    dx,al
    in    al,dx            ;flush status.

;Start receiver
    mov    ax,0            ;Reset read pointer
    setport    IE_RP
    out    dx,ax
    mov    al,IE_RIDE or IE_RCVEDLC
    setport    IE_CSR
    out    dx,al

    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.

    clc
    ret

    public    print_parameters
print_parameters:
    mov    di,offset int_no
    mov    dx,offset int_no_name
    call    print_number
    mov    di,offset io_addr
    mov    dx,offset io_addr_name
    call    print_number
    ret


code    ends

    end