Chip 1994 February/CHIP0294.ISO/digital/magazin/trumpet/pktdrvs/exos205.asm

Assembly Source File | 1993-11-13 | 12.7 KB | 495 lines

version    equ    1

    include    defs.asm

; a driver for the EXOS 205 Ethernet controller by Dirk Koeppen ([e-mail])

; 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.


    public    int_no
    public    driver_class, driver_type, driver_name, driver_function
    public    parameter_list
    public    usage_msg
    public    copyright_msg
    public    parse_args
    public    print_parameters

; inform 82586.asm that we have a larger amount of memory
SEG586    equ    0fh

; equates for controlling EXOS 205 i/o ports
P_INTR        EQU    0        ; interrupt EXOS 205
P_CTRL1        EQU    2        ; control port 1
    P1_186    EQU     00000001b    ; enable 80186
    P1_586    EQU     00000010b    ; enable 82586
    P1_A12    EQU     00000100b    ; address bit 12 of EXOS memory
    P1_NET    EQU    00001000b    ; enable net (disable loopback)
    P1_A13    EQU    00010000b    ; address bit 13 of EXOS memory
    P1_CA    EQU    00100000b    ; do a channel attention by host
    P1_A14    EQU    01000000b    ; address bit 14 of EXOS memory
    P1_A15    EQU    10000000b    ; address bit 15 of EXOS memory
P_CTRL2        EQU    3        ; control port 2
    P2_A16    EQU    00000001b    ; address bit 16 of EXOS memory
    P2_SHM    EQU    01111110b    ; EXOS shared memory address on host
    P2_ACC    EQU    10000000b    ; enable access to EXOS memory
P_ACK        EQU    4        ; acknowledge interrupt


; here are some equates to syncronise the i186 and the host via a semaphore
S_INST        EQU    0aah        ; a fancy value to flag installed code
S_EXEC        EQU    0a5h        ; .. code is executing
S_FAILED    EQU    05ah        ; .. i186 has failed to execute code
S_STOP        EQU    055h        ; .. code was successfully executed


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

int_no        db    2, 0, 0, 0    ; interrupt number
io_addr        dw    310h, 0        ; I/O address for card
base_addr    dw      0cc00h, 0    ; base segment for board

ex_eaddr    db      6 dup (0)    ; boards Ethernet address
ex_ctrl1    db    0        ; copy of control port 1
ex_ctrl2    db    0        ; .. port2

driver_class    db    BLUEBOOK, IEEE8023, 0    ; from the packet spec
driver_type    db    13            ; from the packet spec
driver_name    db    "EXOS205", 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

usage_msg    db "usage: exos205 [options] <packet_int_no> [int_no] [io_addr] [base_addr]",CR,LF,'$'

copyright_msg    db    "Packet driver for the EXOS 205, version ",'0'+(majver / 10),'0'+(majver mod 10),".",'0'+version,".",'0'+i82586_version,CR,LF
        db    "Portions Copyright 1988 The Board of Trustees of the University of Illinois.",CR,LF
        db    "Portions Copyright 1992 Dirk Koeppen ([e-mail]).",CR,LF,'$'

no_exos205    db    "Unable to initialize the EXOS 205 adapter.",CR,LF,'$'

int_no_name    db    "Interrupt number ",'$'
io_addr_name    db    "I/O port ",'$'
base_addr_name    db    "Shared memory address ",'$'


; ENABLE_NETWORK - switch on the transceiver
enable_network:
    ret        ; is on all the time


; RESET_586 - reset the network controller
reset_586:
    push    ds        ; could be called from different segment
    push    ax
    mov    ax, cs
    mov    ds, ax

    loadport
    setport P_CTRL1        ; load the i/o control register
    mov    al, ex_ctrl1
    or    al, P1_CA    ; set CA
    and    al, NOT P1_586    ; disable i82586
    out    dx, al        ; trigger the port
    jmp    $+2        ; let the signal dry
    or    al, NOT P1_586    ; enable i82586
    out    dx, al
    mov    ex_ctrl1, al    ; save a copy
    pop    ax
    pop    ds
    ret


; DOCA - do a channel attention
doca:
    push    ds        ; could be called from different segment
    push    ax
    mov    ax, cs
    mov    ds, ax

    loadport
    setport P_CTRL1        ; load the i/o control register
    mov    al, ex_ctrl1
    and    al, NOT P1_CA    ; clear CA
    or    al, P1_586    ; enable i82586 if not already enabled
    out    dx, al        ; trigger the port
    jmp    $+2        ; let the signal dry
     jmp    $+2
    or    al, P1_CA    ; set CA
    out    dx, al
    mov    ex_ctrl1, al    ; save a copy

    setport    P_ACK        ; acknowledge intr (placed here because
    out    dx, ax        ; .. recv_isr calls doca each time)

    pop    ax
    pop    ds
    ret


; EX_INIT - initialize the EXOS205
ex_init:
    loadport        ; base of device
    mov    ex_ctrl1, P1_NET+P1_A12+P1_A13+P1_A14+P1_A15 ; highest mem page

    mov    ax, base_addr    ; where the shared memory should get to
    shr    ah, 1         ; shift it to the right place
    and    ah, P2_SHM    ; zero all other bits
    or    ah, P2_A16    ; set address bit 16
    mov    ex_ctrl2, ah

    setport    P_CTRL1        ; set the EXOS memory address
    mov    al, ex_ctrl1
    out    dx, al

    setport    P_CTRL2
    mov    al, ex_ctrl2
    out    dx, al
    jmp    $+2        ; let it dry
    jmp    $+2
    or    ex_ctrl2, P2_ACC ; enable the memory
    mov    al, ex_ctrl2
    out    dx, al

init_i186:
    push    es        ; save 'C' register type loop-counters
    push    si
    push    di
    push    ds
    mov    es, base_addr    ; ES:DI -> EXOS205 memory (end of last 16K page)
    mov    di, 03fffh
    mov    ax, cs        ; DS:SI -> code to be downloaded (end of code)
    mov    ds, ax
    mov    si, offset i186_end
    mov    cx, (offset i186_end-offset i186_code) ; amount to be downloaded
    inc    cx        ; one more because loops end at 0
    std            ; copy backwards

    rep    movsb        ; copy the code

    cld
    pop    ds        ; restore original DS
    mov    di, 03fffh     ; where the semaphore is located
    sub     di, (offset i186_end-offset i186_sema)
    mov    al, es:[di]    ; get semaphore
    cmp    al, S_INST    ; check if code is installed
    jne    init_failed    ; failed to init board

    setport    P_CTRL1
    mov    al, ex_ctrl1    ; release the i186, let it execute the code
    or    al, P1_186
    mov    ex_ctrl1, al    ; .. and let it run forever
    out    dx, al

    mov    ax, (36*2)    ; give it 2 seconds to start execution
    call    set_timeout

init_loop1:
    mov    al, es:[di]    ; get semaphore
    cmp    al, S_EXEC    ; does it execute ?
    je    init_i186exec

    call    do_timeout    ; loop until timeout
    jne    init_loop1

    jmp    init_failed    ; failed to init board

init_i186exec:
    mov    ax, (36*5)    ; give it 5 seconds to initialize
    call    set_timeout

init_loop2:
    mov    al, es:[di]    ; get semaphore
    cmp    al, S_STOP    ; did it stop ?
    je    init_i186stop

    call    do_timeout    ; loop until timeout
    jne    init_loop2

    jmp    init_failed    ; failed to init board

init_i186stop:
    xor    ax, ax         ; flag that everything worked all right
    push    ax
    mov    di, 03fffh     ; where the Ethernet address is located
    sub     di, (offset i186_end-offset i186_addr)
    mov    bx, offset ex_eaddr
    mov    cx, 6        ; 6 bytes to move

init_acpy:
    mov    al, es:[di]    ; copy address
    mov    ds:[bx], al
    inc    di        ; next byte
    inc    bx
    loop    init_acpy    ; loop for all byte

init_end:
    pop    ax

    setport    P_ACK        ; acknowledge intr to reset hardware logic
    out    dx, ax

    pop    di         ; restore saved registers
    pop    si
    pop    es
    or    ax, ax        ; setup zero flag
    ret

init_failed:
    setport    P_CTRL1        ; stop the i186
    mov    al, ex_ctrl1
    and    al, NOT P1_186    ; .. forever
    mov    ex_ctrl1, al
    out    dx, al
    mov    ax, -1        ; failed to init board
    push    ax
    jmp    init_end


; I186_CODE - this code is downloaded to the EXOS205 to be executed by the i186
i186_code:
i186_addr:
    db    08h, 00h, 14h    ; unique EXOS Ethernet address (byte 5-3)
    db    0, 0, 0        ; .. byte 2-0 of the boards Ethernet address

i186_sema:
    db    S_INST        ; semaphore will be S_STOP if code was executed

i186_ipl:            ; i186 bootstrap
    cli            ; disable interrupts
    xor    ax, ax        ; zero relocation register
    mov    dx, 0fffeh
    out    dx, ax
    mov    ax, 0fff8h    ; setup UMCS register
    out    0a0h, ax
    mov    ax, 0007ch    ; .. PACS register
    out    0a4h, ax
    mov    ax, 080bch    ; .. MPCS register
    out    0a8h, ax

    mov    ax, cs        ; DS -> CS
    mov    ds, ax

    ; flag code execution
    mov    bx, 00fffh - (offset i186_end-offset i186_sema)
    mov    byte ptr ds:[bx], S_EXEC
    xor    cx, cx

i186_wait:            ; spend some time to let host read the semaphore
    jmp    $+2
    jmp    $+2
    jmp    $+2
    loop    i186_wait

    ; where to write the boards Ethernet addr to (starts 3 bytes after code)
    mov    si, 00fffh - (offset i186_end-offset i186_addr) + 3

    mov    dx, 0502h    ; low order nibble of byte 2 Ethernet address
    xor    bx, bx        ; zero checksum
    mov    cx, 3        ; 3 bytes of Ethernet address are to be read

i186_acpy:
    in    al, dx        ; read one nibble
    and    al, 00001111b    ; .. mask valid bits (just to get shure !)
    mov    ah, al        ; .. store it
    add    bl, al        ; .. add to checksum
    inc    dx         ; go to high order nibble
    inc    dx
    in    al, dx        ; .. read it
    add    bl, al        ; .. add to checksum
    shl    al, 1         ; .. shift it to be high order nibble
    shl    al, 1
    shl    al, 1
    shl    al, 1
    or    al, ah        ; pack those two nibbles into one byte
    mov    ds:[si], al     ; .. and store the byte

    inc    dx        ; go to next nibble of Ethernet address
    inc    dx
    inc    si
    loop    i186_acpy    ; loop until all 3 bytes are read

    mov    ah, bl        ; add bottom to top nibble
    shr    ah, 1        ; top nibble
    shr    ah, 1
    shr    ah, 1
    shr    ah, 1
    and    bl, 00001111b    ; bottom nibble
    add    ah, bl        ; add them
    xor    ah, 5        ; is x-ored by 5 to avoid 0x00 or 0xff problem

    in    al, dx        ; DX -> checksum
    cmp    ah, al
    je    i186_ok

    mov    byte ptr ds:[si], S_FAILED; flag that checksum failed

    jmp    $        ; stop execution (i186 will be stopped by host)

i186_ok:
    mov    byte ptr ds:[si], S_STOP ; flag that we have stopped execution
    xor    ax, ax        ; set the interrupt vector
    mov    ds, ax        ; .. i82586 is connected to INT2
    mov    si, 4*14    ; INT2 has vector type 14
    mov    word ptr ds:[si], 00fffh - (offset i186_end-offset i186_intr)
    inc    si
    inc    si
    mov    word ptr ds:[si], 0ff00h

    sti            ; enable interrupts

    mov    dx, 3ch        ; INT2 control register
    mov    ax, 3        ; level triggered, unmasked and prio 3
    out    dx, ax

    xor    bx, bx        ; zero counters
    xor    cx, cx
    mov    bp, 00fffh - (offset i186_end-offset i186_lcnt)

i186_loop:            ; endless loop to keep i186 doing something
    nop
    nop
    nop
    nop
    loop    i186_loop

    inc    bx        ; count
    mov    cs:[bp], bx    ; .. and store for debugging
    jmp    i186_loop    ; cycle endless while waiting for interrupts

i186_intr:            ; interrupt routine called by 82586 intr
    push    dx
    mov    dx, 00600h    ; interrupt host first
    out    dx, ax

    push    ax
    push    bx
    push    bp

    mov    bp, 00fffh - (offset i186_end-offset i186_icnt)
    mov    bx, cs:[bp]
    inc    bx        ; increment interrupt counter
    mov    cs:[bp], bx    ; .. and store for debugging

    mov    dx, 22h        ; acknowledge interrupt
    mov    ax, 8000h
    out    dx, ax

    pop    bp
    pop    bx
    pop    ax
    pop    dx
    iret

    db    'INTR cnt->'    ; some debugging variables
i186_icnt:
    dw    0        ; counts 82586 interrupts
    db    'LOOP cnt->'
i186_lcnt:
    dw    0        ; loops to flag execution

i586_reset_vector:
    db    0eah    dup (0)    ; reserved for the i82586 reset vector

i186_reset_vector:
    db    0eah        ; opcode 'jmp far'
    dw    00fffh - (offset i186_end-offset i186_ipl)
    dw    0ff00h
    db    0, 0, 0, 0, 0, 0, 0, 0, 0, 0 ; fill patterns

i186_end:
    db    0        ; one more fill pattern


; here we include the code that is common between 82586 implementations.
; everything above this is resident.
    include    82586.asm
; everything below this is discarded upon installation.

; CHECK_BOARD - check if there really is a EXOS 205 installed
check_board:
    mov    SCP, 0            ; 16 bit bus type in scb.

    call    ex_init            ; setup the board
    je    check_ok

    mov    dx, offset no_exos205    ; failed to init board
    jmp    error

check_ok:
    xor    ax, ax            ; have a return value
    ret


; PARSE_ARGS - read the command line option and overwrite defaults
parse_args:
    mov    di, offset int_no
    call    get_number
    mov    di, offset io_addr
    call    get_number
    mov    di, offset base_addr
    call    get_number
    clc
    ret

; PRINT_PARAMETERS - print out the boards configuration 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
    mov    ax, memory_begin
    mov    cl, 4
    shr    ax, cl
    add    base_addr, ax
    push    ax
    mov    di, offset base_addr
    mov    dx, offset base_addr_name
    call    print_number
    pop    ax
    sub    base_addr, ax
    ret

; GET_ADDRESS - get boards Ethernet address
;    enter with es:di -> place to get the address,
;        cx = size of address buffer.
;    exit with nc, cx = actual size of address,
;         or cy if buffer not big enough.
get_address:
    assume    ds: code
    mov    bx, offset ex_eaddr    ; where to copy is located
get_address_1:
    mov    al, ds:[bx]        ; copy a byte of the address
    stosb                ; put it away
    inc    bx            ; next address byte
    loop    get_address_1        ; go back for rest
    ret

    include    memtest.asm

code    ends
    end