Category : Network Files
Archive   : TCP_SRC.ZIP
Filename : NE2.ASM

; Packet driver for Novell's NE/2
; Written by:
; Eric Henderson
; Brigham Young University
;
; Based on the "generic" packet driver by Russell Nelson with help
; from the western digital pd by Russell Nelson.
; 80[123]86 processor support lifted from 3com driver by permission
; from Russell Nelson
;
; Portions (C) Copyright 1990 BYU

version equ 5

.286
include defs.asm

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

;*****************************************************************************
;
; NE/2 controller board offsets
; IO port definition (BASE in io_addr)
;*****************************************************************************
ADDROM EQU 10h ; LAN Address ROM
RACK EQU 10h ; NE2 Port Window
NERESET EQU 20h ; Issue a read for reset

; 8390 LAN Controller (page0) register offset for read and write
CMDR EQU 00h ; command register for read & write
CLDA0 EQU 01h ; current local dma addr 0 for read
PSTART EQU 01h ; page start register for write
CLDA1 EQU 02h ; current local dma addr 1 for read
PSTOP EQU 02h ; page stop register for write
BNRY EQU 03h ; boundary reg for rd and wr
TSR EQU 04h ; tx status reg for rd
TPSR EQU 04h ; tx start page start reg for wr
NCR EQU 05h ; number of collision reg for rd
TBCR0 EQU 05h ; tx byte count 0 reg for wr
FIFO EQU 06h ; FIFO for rd
TBCR1 EQU 06h ; tx byte count 1 reg for wr
ISR EQU 07h ; interrupt status reg for rd and wr
CRDA0 EQU 08h ; current remote dma address 0 for rd
RSAR0 EQU 08h ; remote start address reg 0 for wr
CRDA1 EQU 09h ; current remote dma address 1 for rd
RSAR1 EQU 09h ; remote start address reg 1 for wr
RBCR0 EQU 0Ah ; remote byte count reg 0 for wr
RBCR1 EQU 0Bh ; remote byte count reg 1 for wr
RSR EQU 0Ch ; rx status reg for rd
RCRWD EQU 0Ch ; rx configuration reg for wr
CNTR0 EQU 0Dh ; tally cnt 0 for frm alg err for rd
TCR EQU 0Dh ; tx configuration reg for wr
CNTR1 EQU 0Eh ; tally cnt 1 for crc err for rd
DCR EQU 0Eh ; data configuration reg for wr
CNTR2 EQU 0Fh ; tally cnt 2 for missed pkt for rd
IMR EQU 0Fh ; interrupt mask reg for wr
; 8390 LAN Controller (page1) register offset for read and write
PAR0 EQU 01h ; physical addr reg 0 for rd and wr
PAR1 EQU 02h ; physical addr reg 1 for rd and wr
PAR2 EQU 03h ; physical addr reg 2 for rd and wr
PAR3 EQU 04h ; physical addr reg 3 for rd and wr
PAR4 EQU 05h ; physical addr reg 4 for rd and wr
PAR5 EQU 06h ; physical addr reg 5 for rd and wr
CURR EQU 07h ; current page reg for rd and wr
MAR0 EQU 08h ; multicast addr reg 0 fro rd and WR
MAR1 EQU 09h ; multicast addr reg 1 fro rd and WR
MAR2 EQU 0Ah ; multicast addr reg 2 fro rd and WR
MAR3 EQU 0Bh ; multicast addr reg 3 fro rd and WR
MAR4 EQU 0Ch ; multicast addr reg 4 fro rd and WR
MAR5 EQU 0Dh ; multicast addr reg 5 fro rd and WR
MAR6 EQU 0Eh ; multicast addr reg 6 fro rd and WR
MAR7 EQU 0Fh ; multicast addr reg 7 fro rd and WR

;***********************************************************************
;
; 8003 control register operations
;***********************************************************************

MSK_RESET EQU 80h ; reset LAN controller
MSK_ENASH EQU 40h ; enable PC access to shared mem
MSK_DECOD EQU 3Fh ; ???? memory decode bits, corresponding
; to SA 18-13. SA 19 assumed to be 1
;***********************************************************************
;
; 8390 CMDR MASK
;***********************************************************************

MSK_STP EQU 01h ; software reset, take 8390 off line
MSK_STA EQU 02h ; activate the 8390 NIC
MSK_TXP EQU 26h ; initial txing of a frm (With DMA)
MSK_RD2 EQU 20h ; abort remote DMA
MSK_PG0 EQU 00h ; select register page 0
MSK_PG1 EQU 40h ; select register page 1
MSK_PG2 EQU 80h ; select register page 2
MSK_DMA_RD EQU 0ah ; start DMA read
MSK_DMA_WR EQU 12h ; start DMA write

;***********************************************************************
;
; 8390 ISR & IMR MASK
;***********************************************************************

MSK_PRX EQU 01h ; rx with no error
MSK_PTX EQU 02h ; tx with no error
MSK_RXE EQU 04h ; rx with error
MSK_TXE EQU 08h ; tx with error
MSK_OVW EQU 10h ; overwrite warning
MSK_CNT EQU 20h ; MSB of one of the tally counters is set
MSK_RDC EQU 40h ; remote dma completed
MSK_RST EQU 80h ; reset state indicator
MaskByte equ 0
UnmaskByte equ 1fh
InterruptMask equ 0fh

;***********************************************************************
;
; 8390 DCR MASK
;***********************************************************************

MSK_WTS EQU 01h ; word transfer mode selection
MSK_BOS EQU 02h ; byte order selection
MSK_LAS EQU 04h ; long addr selection
MSK_BMS EQU 08h ; burst mode selection
MSK_ARM EQU 10h ; atuoinitialize remote
MSK_FT00 EQU 00h ; burst lrngth selection
MSK_FT01 EQU 20h ; burst lrngth selection
MSK_FT10 EQU 40h ; burst lrngth selection
MSK_FT11 EQU 60h ; burst lrngth selection

;***********************************************************************
;
; 8390 RCR MASK
;***********************************************************************

MSK_SEP EQU 01h ; save error pkts
MSK_AR EQU 02h ; accept runt pkt
MSK_AB EQU 04h ; accept broadcast
MSK_AM EQU 08h ; accept multicast
MSK_PRO EQU 10h ; promiscuous physical
; accept all pkt with physical adr
MSK_MON EQU 20h ; monitor mode

;***********************************************************************
;
; 8390 TCR MASK
;***********************************************************************

MSK_CRC EQU 01h ; inhibit CRC, do not append crc
MSK_LB01 EQU 06h ; encoded loopback control
MSK_ATD EQU 08h ; auto tx disable
MSK_OFST EQU 10h ; collision offset enable

;***********************************************************************
;
; 8390 RSR MASK
;***********************************************************************

SMK_PRX EQU 01h ; rx without error
SMK_CRC EQU 02h ; CRC error
SMK_FAE EQU 04h ; frame alignment error
SMK_FO EQU 08h ; FIFO overrun
SMK_MPA EQU 10h ; missed pkt
SMK_PHY EQU 20h ; physical/multicase address
SMK_DIS EQU 40h ; receiver disable. set in monitor mode
SMK_DEF EQU 80h ; deferring

;***********************************************************************
;
; 8390 TSR MASK
;***********************************************************************

SMK_PTX EQU 01h ; tx without error
SMK_DFR EQU 02h ; non deferred tx
SMK_COL EQU 04h ; tx collided
SMK_ABT EQU 08h ; tx aboort because of excessive collisions
SMK_CRS EQU 10h ; carrier sense lost
SMK_FU EQU 20h ; FIFO underrun
SMK_CDH EQU 40h ; collision detect heartbeat
SMK_OWC EQU 80h ; out of window collision

;***********************************************************************
;
; on board memory constant definition
;***********************************************************************
; for rcv buff ring of onboard mem
START_PG EQU 46h ; start at page 46
STOP_PG EQU 80h ; end at page 80
; for tx buff of shr mem
TB_SIZE EQU 1 ; number of tb buff in shr mem
TB_PGNO EQU 6 ; number of pages in one tb buff

EIGHTBITSLOT db 0 ;8-bit machine flag
Path dw ?
RxPath dw ?

extrn is_at: byte

public int_no, io_addr
int_no db 3,0,0,0 ;must be four bytes long for get_number.
io_addr dw 1000h,0 ; I/O address for card (jumpers)
my_eaddr db 6 dup(?) ; 6 byte LAN address
m_channel dw 0 ; micro channel flag
is_186 db 0 ;=0 if 808[68], =1 if 80[123]86.

rd_NE MACRO port
mov DX, CS:io_addr
add DX, port ; DX contains address of port
in AL, DX ; AL contains data read from port
ENDM

wr_NE MACRO port
mov DX, CS:io_addr
add DX, port ; DX contains address of port
out DX, AL ; AL contains data to be written to port
ENDM

ReceiveHeaderStructure struc
RReceiveStatus db ?
RNextBuffer db ?
RByteCount dw ?

RDestinationAddress db 6 dup(?)
RSourceAddress db 6 dup(?)
RPacketLength dw ?
RChecksum dw ?
RRPacketLength dw ?
RTranControl db ?
RHPacketType db ?
RDestinationNet db 4 dup(?)
RDestinationNode db 6 dup(?)
RDestinationSocket dw ?
ReceiveHeaderStructure ends

ReceiveHeader ReceiveHeaderStructure <>

Current equ InterruptStatus
CurrentDMA0 equ RemoteStartAddress0
CurrentDMA1 equ RemoteStartAddress1
ForRSTBit equ 80h

NIC struc
Command db ?
PageStart db ?
PageStop db ?
Boundry db ?
TransmitStatus db ?
TransmitByteCount0 db ?
TransmitByteCount1 db ?
InterruptStatus db ?
RemoteStartAddress0 db ?
RemoteStartAddress1 db ?
RemoteByteCount0 db ?
RemoteByteCount1 db ?
ReceiveConfiguration db ?
TransmitConfiguration db ?
DataConfiguration db ?
IntMask db ?
DataPort db ?
db 15 dup (?)
Reset db ?
NIC ends

BLUEBOOK equ 1
IEEE8023 equ 11
public driver_class, driver_type, driver_name, driver_function, parameter_list
driver_class db BLUEBOOK, IEEE8023, 0 ;from the packet spec

driver_type dw 0ffffh ;Wild card matches any type
driver_name db 'NE/2',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
dw 0 ;Interrupt # to hook for post-EOI
;processing, 0 == none,

mcast_list_bits db 0,0,0,0,0,0,0,0 ;Bit mask from last set_multicast_list
mcast_all_flag db 0 ;Non-zero if hware should have all

public rcv_modes
rcv_modes dw 7 ;number of receive modes in our table.
dw 0 ;there is no mode 1.
dw rcv_mode_1
dw rcv_mode_2
dw rcv_mode_3
dw rcv_mode_4
dw rcv_mode_5
dw rcv_mode_6
rxcr_bits db MSK_AB ; Default to ours plus multicast


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 ds:si -> packet, cx = packet length.
;exit with nc if ok, or else cy if error, dh set to error number.
assume ds:nothing
; get txblk length
inc cx
and cl, 0feh
cmp CX, RUNT
jnb length_ok
mov cx, RUNT
length_ok:
cmp cx, GIANT
jbe length1_ok
mov dh, NO_SPACE
stc
jmp count_out_err
length1_ok:
;new stuff
mov AX, CX
wr_NE TBCR0 ; Transmit byte count

mov al, ah
wr_NE TBCR1
mov al, 0
wr_NE RSAR0
mov al, 40h
wr_NE RSAR1
mov ax, cx
wr_NE RBCR0 ; Remote byte count
mov al, ah
wr_NE RBCR1

; Clear out DMA complete interrupt
mov al, MSK_PG0
wr_NE CMDR
mov al, 40h
wr_NE ISR

mov al, MSK_DMA_WR
wr_NE CMDR

mov DX, CS:io_addr
add DX, RACK ; DX has address NE/2 Port window

shr cx, 1
rep outsw

xor cx, cx ; Prevent infinite loop
WaitForDMAComplete:
rd_NE ISR
test al, 40h
jnz DMAComplete
loop WaitForDMAComplete

DMAComplete:
mov al, MSK_TXP
wr_NE CMDR
clc
exit_now:
ret


public get_address
get_address:
;get the address of the interface.
;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.
assume ds:code
cmp cx, EADDR_LEN ; Caller wants a reasonable length?
jb get_addr_x ; No, fail.
mov cx, EADDR_LEN ; Yes. Set count for loop
mov si, offset cs:my_eaddr
cld ; Make sure string mode is right
rep movsb
mov cx, EADDR_LEN ; Tell caller how many bytes we fed him
clc ; Carry off says success
ret
get_addr_x:
stc ; Tell caller our addr is too big for him
ret


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.
;This proc will set the first CX bytes of the ethernet address, leaving
; the rest unchanged.
assume ds:nothing

cmp cx, 6
jbe set1
mov dh, BAD_ADDRESS
stc
ret
set1:
push es
push di
mov di, offset my_eaddr
mov ax, cs
mov es, ax

mov al, 61h
wr_NE CMDR
mov DX, CS:io_addr
add DX, PAR0 ; DX has address 8390 Phys Address Reg
AddressToChip1:
lodsb
out dx, al
mov es:[di], al
inc di
inc dx
nop
nop
nop
nop
loop AddressToChip1
pop di
pop es

mov al, 21h
wr_NE CMDR
clc
ret

; Routines to set address filtering modes in the DS8390
; This was lifted from R. Clements' WD PD
rcv_mode_1: ; Turn off receiver
mov al, MSK_MON ; Set to monitor for counts but accept none
jmp short rcv_mode_set
rcv_mode_2: ; Receive only packets to this interface
mov al, 0 ; Set for only our packets
jmp short rcv_mode_set
rcv_mode_3: ; Mode 2 plus broadcast packets (This is the default)
mov al, MSK_AB ; Set four ours plus broadcasts
jmp short rcv_mode_set
rcv_mode_4: ; Mode 3 plus selected multicast packets
mov al, MSK_AB+MSK_AM ; Ours, bcst, and filtered multicasts
mov mcast_all_flag,0
jmp short rcv_mode_set
rcv_mode_5: ; Mode 3 plus ALL multicast packets
mov al, MSK_AB+MSK_AM; Ours, bcst, and filtered multicasts
mov mcast_all_flag,1
jmp short rcv_mode_set
rcv_mode_6: ; Receive all packets (Promiscuous physical plus all multi)
mov al, MSK_AB+MSK_AM+MSK_PRO
mov mcast_all_flag,1
rcv_mode_set:
push ax ; Hold mode until masks are right
call set_8390_multi ; Set the multicast mask bits in chip
pop ax
WR_NE RCRWD
mov rxcr_bits,al ; Save a copy of what we set it to
ret

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

; Set the multicast filter mask bits in case promiscuous rcv wanted
; This was lifted from R. Clements' WD PD
set_8390_multi:

mov al,MSK_RD2+MSK_PG1
WR_NE CMDR
mov cx,8 ; Eight bytes of multicast filter
mov si,offset mcast_list_bits ; Where bits are, if not all ones
push cs
pop ds
cli ; Protect from irq changing page bits

mov DX, CS:io_addr
add DX, MAR0
mov al,mcast_all_flag ; Want all ones or just selected bits?
or al,al
jz set_mcast_2 ; z = just selected ones
mov al,0ffh ; Ones for filter
set_mcast_all:
out dx, al
inc dl ; Step to next one
jmp $+2 ; limit chip access rate
loop set_mcast_all
jmp short set_mcast_x

set_mcast_2:
lodsb ; Get a byte of mask bits
out dx,al ; Write a mask byte
inc dl ; Step to next I/O register
jmp $+2 ; limit chip access rate
loop set_mcast_2
set_mcast_x:
mov al, MSK_RD2+MSK_PG0
WR_NE CMDR
sti ; OK for interrupts now
ret


public terminate
terminate:
ret


public get_multicast_list
get_multicast_list:
;return with nc, es:di ->list of multicast addresses, cx = number of bytes.
;return cy, NO_ERROR if we don't remember all of the addresses ourselves.
;return cy, NO_MULTICAST if we don't implement multicast.
mov dh,NO_MULTICAST
stc
ret


public reset_interface
reset_interface:
;reset the interface.
assume ds:code
mov al, MSK_STP + MSK_RD2
wr_NE CMDR
mov al, 0ffh ; Clear all pending interrupts
wr_NE ISR
xor al, al ; Turn off all enables
wr_NE IMR
wr_NE NERESET ; Hard reset NE/2
wr_NE NERESET
wr_NE NERESET
wr_NE NERESET
wr_NE NERESET
wr_NE NERESET
wr_NE NERESET
wr_NE NERESET

rd_NE NERESET

mov al, 21h
wr_NE CMDR
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.
;It returns with es:di = 0 if don't want this type or if no buffer available.
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

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.
;Actually, not just receive, but all interrupts come here.
;Upon exit, the interrupt will be acknowledged.
assume ds:code

; read irq status register
mov al, MaskByte
wr_NE IMR
sti
rd_isr:
rd_NE ISR ; read isr into AL
and AL, 3Fh ; check bit0-bit5, if all 1's no irq
cmp AL, 0 ; if any irq
jne tst_ovw ; some irq
cli
mov al, UnmaskByte
wr_NE IMR
ret ; no more irq, exit

; process OVW (OVW = 1)
; may report error here
tst_ovw:
test AL, MSK_OVW ; if OVW irq
jnz prcs_ov ; OVW (OVW = 1)
jmp test_rx ; no OVW (OVW = 0)

; **************************************************************
; follow the DP8390 datasheet addendum to handle the buff ring overflow
prcs_ov:
; 1. issue a STOP mode command
mov AL, MSK_STP + MSK_RD2
wr_NE CMDR
; 6. remove one packet from the ring
rd_NE BNRY ; BNRY in AL
add AL, 1 ; start page of frm in AL
cmp AL, STOP_PG ; check boundary
jne get1
mov AL, START_PG
; ring not empty
get1:
mov BH, AL ; BX has the rx_frm pointer
mov al, SIZE ReceiveHeader
wr_NE RBCR0
xor al, al
wr_NE RBCR1
wr_NE RSAR0
mov al, bh
wr_NE RSAR1
mov al, MSK_DMA_RD
wr_NE CMDR

mov DX, CS:io_addr
add DX, RACK ; DX has address NE/2 Port window
mov di, OFFSET ReceiveHeader
mov ax, cs
mov es, ax
mov cx, SIZE ReceiveHeader
shr cx, 1
Receive1:
rep insw

SkipReceive1:
mov bx, offset ReceiveHeader
mov AL, CS:[BX] ; AL has the status byte
test AL, SMK_PRX ; if rx good
jz fd_bnr ; rx error, drop frm by forward bnry

; good frm, call _rcv_frm
call _rcv_frm

fd_bnr: ;drop frm by forward BNRY
mov al, cs:ReceiveHeader.RNextBuffer ; al = next pointer
sub AL, 1 ; new BNRY in AL
cmp AL, START_PG ; check boundary
jae wrbnr ; unsigned arithmetic
mov AL, STOP_PG - 1 ;
; dec AL ;
wrbnr:
wr_NE BNRY
; 2. clear the remote byte count registers (RBCR0,RBCR1)
xor AL, AL
wr_NE RBCR0
wr_NE RBCR1
; 3. poll the ISR for the RST bit
plisr:
mov cx, 0ffffh
rd_NE ISR
test AL, MSK_RST
jnz plisr_ok
loop plisr ; keep polling until the RST bit set
; 4. place the NIC in loopback mode (mode 1 or 2) by writing 02 or 04 to TCR
plisr_ok:
mov AL, 02h ; put it in mode 2 (internal loopback)
wr_NE TCR
; 5. issue start mode command
mov AL, MSK_STA + MSK_RD2
wr_NE CMDR
; 7. out from loopback mode by writing 00 to TCR
xor AL, AL
wr_NE TCR ; normal operation configuration
; clear OVW in ISR
mov AL, MSK_OVW

wr_NE ISR ; clear OVW
call count_in_err ; increment overflow counter
jmp rd_isr ; back to the top


; end of the modification
; *****************************************************
;
;process PRX and RXE
;
test_rx:
test AL, MSK_RXE
jnz prcs_rxe ; RXE = 1
test AL, MSK_PRX
jnz prcs_rx ; PRX = 1
jmp test_tx

prcs_rxe:
call count_in_err
mov al, MSK_RXE
wr_NE ISR
jmp rd_isr
prcs_rx:
mov AL, MSK_PG1 + MSK_RD2 ; read CURR reg
wr_NE CMDR
rd_NE CURR
mov BL, AL ; CURR in BL
mov AL, MSK_PG0 + MSK_RD2 ; read BNRY reg
wr_NE CMDR
rd_NE BNRY ; BNRY in AL
add AL, 1 ; start page of frm in AL
cmp AL, STOP_PG ; check boundary
jne go_cmp
mov AL, START_PG ;
go_cmp:
cmp AL, BL
jne Ring_Not_Empty
jmp rd_isr ; buff ring empty

Ring_Not_Empty:
wr_NE RSAR1
xor al, al
wr_NE RBCR1
wr_NE RSAR0
mov al, SIZE ReceiveHeader
wr_NE RBCR0
mov al, MSK_DMA_RD
wr_NE CMDR

mov DX, CS:io_addr
add DX, RACK ; DX has address NE/2 Port window
mov di, OFFSET ReceiveHeader
mov ax, cs
mov es, ax
mov cx, SIZE ReceiveHeader
shr cx, 1

Receive2:
rep insw

SkipReceive2:
mov bx, offset ReceiveHeader
mov AL, CS:[BX] ; AL has the status byte
test AL, SMK_PRX ; if rx good
jz fd_bnry ; rx error, drop frm by forward bnry

; good frm, call _rcv_frm
call _rcv_frm

fd_bnry: ; drop frm by forward BNRY
mov al, CS:ReceiveHeader.RNextBuffer ; al = next pointer
sub AL, 1 ; new BNRY in AL
cmp AL, START_PG ; check boundary
jae wrbnry ; unsigned arithmetic
mov AL, STOP_PG - 1 ;

wrbnry:
wr_NE BNRY
mov al, MSK_PRX
wr_NE ISR
jmp prcs_rx

;process PTX and TXE
test_tx:
test AL, MSK_PTX
jnz prc_ptx ; PTX = 1
test AL, MSK_TXE
jnz prc_txe ; TXE = 1
jmp test_cnt


; process tx good, update txok, lostcrs, collsn
prc_ptx: ; tx good
rd_NE TSR
test AL, SMK_CRS ; is crs set in TSR
jz nocrs ; no
nocrs:
rd_NE NCR ; read number of collision in AL
mov AL, MSK_PTX
wr_NE ISR ; clear PTX
jmp rd_isr

; process tx error, update .txbad .underrun
prc_txe: ; tx bad
call count_out_err
rd_NE TSR
test AL, SMK_FU ; it fu set in TSR
jz nofu ; no
nofu:
mov AL, MSK_TXE
wr_NE ISR ; clear PTX
jmp rd_isr

; process counter overflow, update .algerr .crcerr .???(missed pkt)
test_cnt:
test AL, MSK_CNT
jnz prc_cnt ; yes, process cnt
jmp rd_isr ; no CNT irq, back to the top
; process CNT
prc_cnt:
mov AL, MSK_CNT
wr_NE ISR ; clear CNT
jmp rd_isr ; back to the top

; End of RECV

_rcv_frm:

; read byte count
mov cx, cs:ReceiveHeader.RByteCount ; Extract size of frame
cmp CX, 5dch
jna rxlen_ok
jmp rcv_ret
rxlen_ok:
sub CX, 4 ; 4 control bytes
mov AX, cs
mov ES, AX
mov di, offset cs:ReceiveHeader.RPacketLength
mov dl, BLUEBOOK ;default
mov ax, es:[di]
xchg ah, al
cmp ax, 1500
ja BlueBookPacket
mov di, offset cs:ReceiveHeader.RChecksum
mov dl, IEEE8023
BlueBookPacket:

push cx ; Save frame size
push es

mov ax, cs ; Set ds = code
mov ds, ax
assume ds:code
call recv_find ; See if type and size are wanted
; CX = packet length
; ES:DI = packet type
; ES:DI = packet type

pop ds ; RX page pointer in ds now
assume ds:nothing
pop cx

cld ; Copies below are forward
mov ax, es ; Did recv_find give us a null pointer?
or ax, di ; ..
je no_buff ; If null, don't copy the data
has_buf:

;Tell DMA to copy the whole packet for us
mov ax, 4
wr_NE RSAR0 ; Don't copy 4 8390 control bytes
mov ax, cx ; CX has byte count
wr_NE RBCR0 ; LSB first
mov al, ah
wr_NE RBCR1 ; Now MSB

mov al, MSK_DMA_RD ; Issue DMA read command
wr_NE CMDR

; copy from NE/2 on board memory using the window RACK
; use IN and stosb to do the copy, IN -> AX -> ES:DI (CX has byte count)

copynow:
push cx ; We will want the count and pointer
push es ; to hand to client after copying,
push di ; so save them at this point

mov DX, CS:io_addr
add DX, RACK ; DX has address NE/2 Port window (?)

mov si, cx
shr cx, 1
rep insw
test si, 1
jz call_rc
in ax, dx
stosb
call_rc:
pop si ; Recover pointer to destination
pop ds ; Tell client it's his source
pop cx ; And it's this long
assume ds:nothing
call recv_copy ; Give it to him
jmp short rcv_ret

; no system buff availble to hold rx frm
no_buff:
rcv_ret:
push cs ; Put ds back in code space
pop ds ; ..
assume ds:code
ret



public recv_exiting
recv_exiting:
;called from the recv isr after interrupts have been acknowledged.
;Only ds and ax have been saved.
assume ds:nothing
ret


;any code after this will not be kept after initialization.
end_resident label byte


public usage_msg
usage_msg db "usage: NE2 ",CR,LF,'$'

public copyright_msg
copyright_msg db "Packet driver for NE/2 version "
db '0'+majver,".",'0'+version,CR,LF
db "Portions Copyright 1990, Eric Henderson, BYU",CR,LF,'$'
int_no_name db "Interrupt number ",'$'
io_addr_name db "I/O port ",'$'
no_board_msg:
db "NE/2 apparently not present at this IO address.",CR,LF,'$'
HardwareFailure:
db "The NE/2 is not responding.",CR,LF,'$'
using_186_msg db "Using 80[123]86 I/O instructions.",CR,LF,'$'

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 decout: near
; extrn hexout: near

public parse_args
print_args:
mov dx,offset int_no_name
mov ah,9
int 21h
mov di,offset int_no
mov ax,[di] ;print the number in hex.
mov dx,[di+2]
; call hexout
mov dl,' '
mov ah, 2
int 21h
mov dl,'('
mov ah, 2
int 21h
mov ax,[di] ;print the number in decimal.
mov dx,[di+2]
; call decout
mov dl,')'
mov ah, 2
int 21h
mov dl,CR
mov ah, 2
int 21h
mov dl,LF
mov ah, 2
int 21h
mov dx,offset io_addr_name
mov ah,9
int 21h
mov di,offset io_addr
mov ax,[di] ;print the number in hex.
mov dx,[di+2]
; call hexout
mov dl,' '
mov ah, 2
int 21h
mov dl,'('
mov ah, 2
int 21h
mov ax,[di] ;print the number in decimal.
mov dx,[di+2]
; call decout
mov dl,')'
mov ah, 2
int 21h
mov dl,CR
mov ah, 2
int 21h
mov dl,LF
mov ah, 2
int 21h
parse_args:
ret

extrn etopen_diagn: byte

BoardNotResponding:
mov dx, offset HardwareFailure
mov etopen_diagn, 35
jmp short error_wrt
bad_cksum:
no_memory:
mov dx,offset no_board_msg
mov etopen_diagn,37
error_wrt:
mov ah,9
int 21h
stc
ret

SlotSelectRegister equ 96h
POS0 equ 100h
POS1 equ 101h
POS2 equ 102h
NE2ID equ 7154h

IRQConfiguration label byte ;possible IRQ settings
db 3
db 4
db 5
db 9

IOConfiguration label word ;possible I/O Base addresses
dw 1000h
dw 2020h
dw 8020h
dw 0A0A0h
dw 0B0B0h
dw 0C0C0h
dw 0C3D0h

public etopen
etopen:
;if all is okay,
cli ;Find the NE/2 NIC
mov cl, 7 ; channel position (8=1st slot
; F=8th slot)
NextSlot:
inc cl
cmp cl,10h ;check 8 I/O slots
jne NoHardwareFailure
jmp BoardNotResponding
NoHardwareFailure:
mov al, cl
out SlotSelectRegister, al ;select card slot
mov dx, POS1
in al, dx ;check for NE2 ID
mov ah, al
mov dx, POS0
in al, dx
cmp ax, NE2ID
jne NextSlot

mov dx, POS2 ;read configuration port
in al, dx

test al, 01 ;test to see if card enable
jz NextSlot ; bit is set

mov bl, al
and bx, 000Eh ;mask all but I/O base addr.

jz NextSlot ;check next slot if no option
; setting in POS 2
dec bx
dec bx
mov dx, IOConfiguration[bx] ; IO address
mov io_addr, dx ;save the base I/O address

test al, 10h ;if boot prom enabled then

SetIRQ:
shr al, 5 ;load the hardware config.
and ax, 3 ; table with the IRQ line
mov bx, ax ; value and string
mov dl, IRQConfiguration[bx]
mov int_no, dl ;save interrupt level

; call print_args

;Determine the processor type. The 8088 and 8086 will actually shift ax
;over by 33 bits, while the 80[123]86 use a shift count mod 32.
mov cl,33
mov ax,0ffffh
shl ax,cl
jz not_186
mov is_186,1
mov dx,offset using_186_msg
mov ah,9
int 21h
not_186:

call set_recv_isr ; Put ourselves in interrupt chain

; reset NE/2 board
cli
wr_NE NERESET
wr_NE NERESET
wr_NE NERESET
wr_NE NERESET
wr_NE NERESET
wr_NE NERESET
wr_NE NERESET
wr_NE NERESET

rd_NE NERESET

mov al, 21h
wr_NE CMDR

; Test to see if we're OK
rd_NE CMDR
cmp al, 21h
je WeBeOK
jmp BoardNotResponding

WeBeOK:
mov al, 49h ;Word mode
wr_NE DCR
mov al, 0
wr_NE RBCR0
wr_NE RBCR1
mov al, 4
wr_NE RCRWD
mov al, 02
wr_NE TCR
mov al, START_PG
wr_NE PSTART
wr_NE BNRY
mov al, STOP_PG
wr_NE PSTOP

mov al, 0ffh
wr_NE ISR
mov al, 01fh
wr_NE IMR

mov al, 61h
wr_NE CMDR
mov al, START_PG + 1
wr_NE CURR
mov al, 21h
wr_NE CMDR



mov DX, CS:io_addr
add DX, RACK ; DX has address NE/2 Port window

mov bx, -1 ;setup for Nic's memory test

mov bp, CS:io_addr
call RAMTest ;16 bit memory test

jz memory_OK ;if error, report it
jmp no_memory

memory_OK:
; set up my_eaddr from addr ROM
mov al, 12 ;read 6 bytes from PROM (word mode=12)
wr_NE RBCR0
mov al, 0
wr_NE RBCR1
wr_NE RSAR0
wr_NE RSAR1
mov al, MSK_DMA_RD
wr_NE CMDR

mov DX, CS:io_addr
add DX, RACK ; DX has address NE/2 Port window (?)
mov di, OFFSET my_eaddr
mov ax, cs
mov es, ax
mov cx, 6
GetEnetAddress:
in al, dx
stosb
loop GetEnetAddress

ModeCheckDone:
mov ax, cs
mov ds, ax
mov si, OFFSET my_eaddr
mov cx, 6
call set_address

mov al, 21h
wr_NE CMDR

SetTXPage:
mov al,0C0h ;C000h is used as TX
wr_NE TPSR ;page because of
;spurious writes to
;Ram during transmits
;when collisions occur
mov al, 22h
jmp $+2
wr_NE CMDR

mov al, 0
wr_NE TCR

mov al,0 ;deselect all I/O channels
out SlotSelectRegister,al

mov dx,offset end_resident
sti
clc
ret

;**********************************************************************
;
; RAM Test
;
; assumes:
; BX has the test value
; BP points to IOBase
; NIC (8390) has been set to ignore activity on wire
; (loopback mode) and is set to page 0
;
; returns:
; Z flag set if no error
; BP preserved.
; NIC set to page 0
;
;**********************************************************************

RAMTest proc near

lea dx, [bp].RemoteStartAddress0 ;point at start of RAM
xor al, al
out dx, al
inc dx
mov al, 40h
out dx, al

inc dx ;set byte count=16k
xor al, al ; (both 8k RAM chips)
out dx, al
inc dx
mov al, 40h
out dx, al

lea dx, [bp].Command ;write in all RAM locations
mov al, MSK_DMA_WR ; what we send
out dx, al

lea dx, [bp].DataPort ;point at Nic's data port

mov cx, 2000h ;set count to 8k words

mov ax, bx ;read in test value

WriteLoop:
inc ax ;adjust test pattern
out dx, ax ;send it out to Nic
loop WriteLoop

;now read back and compare
; test pattern from NIC

lea dx, [bp].RemoteStartAddress0 ;point at start of RAM
xor al, al
out dx, al
inc dx
mov al, 40h
out dx, al

inc dx ;set byte count = 16k
xor al, al
out dx, al
inc dx
mov al, 40h
out dx, al

lea dx, [bp].Command ;tell NIC to send back test
mov al, MSK_DMA_RD ; pattern
out dx, al

lea dx, [bp].DataPort ;point at Nic's data port

mov cx, 2000h ;setup loop

ReadLoop:
in ax, dx ;read in test pattern and
inc bx ; compare with original
cmp bx, ax

loopz ReadLoop

ret ;zero flag set if memory error

RAMTest endp

public print_parameters
print_parameters:
;echo our command-line parameters
ret


code ends

end