Chip 1994 February

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Assembly Source File | 1993-09-09 | 16.1 KB | 688 lines

version equ 1 ;History:525,47 0 ; Copyright, 1990-1992, 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. include defs.asm ;some generic information about buffer lengths, etc XMITBUF_LEN equ 800h ;Transmit buffer length RPAGE_LEN equ 128 ;receive page is 128 bytes NUM_RPAGES equ 96 ;There are 96 receive pages NUM_XBUFS equ 2 ;Number of xmit buffers NUM_XBUFS_MASK equ 1 ub_seg segment at 0 org 10h eaddr_rom db 6 dup(?) ;Has serial # in 3 & 4th bytes org 2080h tsa_msb db ? ;transmitter start address, high order 4 ;bits on write, start send on read tsa_lsb db ? ;Transmitter start address, least ;significant byte on write, clear PAV ;on read ;Control / status register (CSR) csr db ? ;Control on write, status on read port ;Command bits TxRdyIntEn equ 080h ;allow TxRdy interrupts PAVIntEn equ 040h ;Allow PAV to gen. intr. SFTInt equ 020h ;generate an interrupt reg. TimIntEn equ 010h ;allow Time interrupt req. ;status bits NTxRdyInt equ 080h ;Not req. TxRdy inter. NPAVInt equ 040h ;Not req. Pav intr. NSFTInt equ 020h ;Not req. SFTInt inter. NTimInt equ 010h ;Not req. timer inter. NRINT equ 008h ;Not req. recv inter. NTINT equ 004h ;Not req. xmit inter. TPOK equ 002h ;Packet okay of some type TXDONE equ 001h ;Transmit done ;Page pointer register definitions ffp label byte ;ffp - first free page register epp label byte ;epp - empty page pointer register pp db ? ;ffp on write/epp on read ;ffp bits NIC_IE equ 080h ;NIC interrupts enable ;epp bits PAV equ 080h ;Page available RPAGE_BITS equ 07fh org 2100h page_ram db NUM_RPAGES dup(?);Receiver buffer pages org 2180h tstatus db ? ;Transmitter status 80 ;Transmit status bits - EDLC TX_READY equ 080h ; TX_BUSY equ 040h ;Carrier detect TX_TPR equ 020h ;Self received packet sent TX_SHORTED equ 010h ;Carrier lost TX_UF equ 008h ;Underflow TX_COL equ 004h ;Collision TX_C16 equ 002h ;16 collisions TX_PE equ 001h ;Parity error TXERRMASK equ TX_PE or TX_C16 or TX_COL or TX_UF or TX_SHORTED or TX_BUSY tmask db ? ;Transmitter mask 81 rstatus db ? ;Receiver status rmask db ? ;Receiver mask 83 tmode db ? ;Transmitter mode 84 rmode db ? ;Receiver mode 85 reset db ? ;Reset line - high on bit 7, 86 tdrlsb db ? ;TDR lsb 87 eaddr_ram db 6 dup(?) ;current Ethernet address. db ? ;Reserved 8e tdrmsb db ? ;TDR msb 8f org 4000h receive_buf label byte org 7000h transmit_buf_1 label byte org 7800h transmit_buf_2 label byte ub_seg ends code segment word public assume cs:code, ds:code public int_no int_no db 3,0,0,0 ;must be four bytes long for get_number. base_addr dw 0d000h,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 8 ;from the packet spec driver_name db 'PC-NIC',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 current_page db 0 ;current receiver page active_buffer dw transmit_buf_1 inactive_buffer dw transmit_buf_2 include movemem.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. ;if we're a high-performance driver, es:di -> upcall. ;exit with nc if ok, or else cy if error, dh set to error number. assume ds:nothing mov es,base_addr assume es:ub_seg cmp cx,GIANT ; Is this packet too large? ja send_pkt_toobig cmp cx,RUNT ; minimum length for Ether jnb oklen mov cx,RUNT ; make sure size at least RUNT oklen: mov di,XMITBUF_LEN ;compute where we're going to sub di,cx ; be putting the packet. ;games above ensure that the last byte of data to go out is at the ;end of the ub xmit buffer, pos is really the offset from the ;start of that buffer mov ax,active_buffer ;swap the buffer pointers. xchg ax,inactive_buffer mov active_buffer,ax add di,ax push di call movemem pop di ;Wait for previous packet to finish first ;could do this with interrupts, etc, but with only 2 xmit buffers ;doesn't seem worth the effort send_pkt_1: mov al,csr and al,TPOK or TXDONE cmp al,TPOK or TXDONE jne send_pkt_1 mov al,tstatus ;get xmiter status ... mov tstatus,0fh ;... and clear status bits test al,TXERRMASK ;any errors? je send_pkt_2 call count_out_err ;yes, count them. send_pkt_2: ;all done above, we can play with TSA now! ;give offset mov ax,di mov tsa_lsb,al mov tsa_msb,ah cmp al,tsa_msb ;Start the send in action (SIDEEFFECT) clc ret send_pkt_toobig: mov dh,NO_SPACE stc 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. assume ds:code 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: mov es,base_addr mov di,offset eaddr_ram rep movsb ; call initialize ;initialize with our new address. set_address_okay: mov cx,EADDR_LEN ;return their address length. clc set_address_done: ret ; 0 - accept no packets rcv_mode_1: mov es,base_addr assume es:ub_seg mov rmode,0 ret rcv_mode_3: ; 1 - accept node id packets, multicasts which match first three ; bytes of node id, and broadcasts mov es,base_addr assume es:ub_seg mov rmode,1 ret ; 2 - accept node id packets, all multicasts and broadcasts rcv_mode_5: mov es,base_addr assume es:ub_seg mov rmode,2 ret ; 3 - take all, promiscous rcv_mode_6: mov es,base_addr assume es:ub_seg mov rmode,3 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 public terminate terminate: mov es,base_addr assume es:ub_seg mov ffp,0 ;set ffp to zero - disabling PAV mov csr,0 ;Turn off interrupt masks here and ... mov tmask,0 ;reset edlc interrupt masks mov rmask,0 mov reset,80h ;Turn on reset line ret public reset_interface reset_interface: ;reset the interface. assume ds:code 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 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 es,base_addr assume es:ub_seg recv_3: test epp,PAV jne recv_4 jmp recv_2 ;yes. recv_4: ;checking against epp is a pain actually... xor cx,cx ;start with zero length mov bl,current_page ;get the first page. xor bh,bh mov dx,bx ;remember the first page. count_pages_1: mov al,page_ram[bx] ;Get page descriptor and al,RPAGE_BITS ;Only page offset bits PLEASE inc al ;Add 1 to offset to make length xor ah,ah add cx,ax ;Add in current page length mov al,page_ram[bx] ;Get page descriptor inc bx ;go to the next page cmp bx,NUM_RPAGES ;wrap around if necessary. jb count_pages_2 xor bx,bx count_pages_2: test al,80h ;End page? je count_pages_1 ;yes, go add this one's length. mov current_page,bl mov ax,dx ;multiply dx by RPAGE_LEN. xchg ah,al ror ax,1 mov di,ax add di,offset receive_buf ;get the starting address. add di,EADDR_LEN+EADDR_LEN ;skip the ethernet addreses and ; point to the packet type. push bx push cx push dx 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 ;look up our type. assume es:nothing pop dx pop cx pop bx mov ax,es ;is this pointer null? or ax,di je just_discard ;yes - just free the frame. push cx push di push es cmp dx,bx ;did we wrap around (first >last?) jbe no_wrap ;no, just do one move. ;we wrapped around the buffer, so we have to move in two halves. ;move the first part. mov ax,dx ;multiply dx by RPAGE_LEN. xchg ah,al ror ax,1 mov si,ax add si,offset receive_buf ;get the starting address. mov ax,NUM_RPAGES ;Compute the number of pages to move. sub ax,dx xchg ah,al ;convert to pages (*RPAGE_LEN). ror ax,1 cmp cx,ax ;are we moving less than that? jbe no_wrap ;yes, just move it. sub cx,ax ;reduce the total count by this count. push cx ;preserve the second part's count mov cx,ax ;get the first part's count. push ds mov ds,base_addr assume ds:nothing call movemem assume ds:code pop ds pop cx ;get back the count xor dx,dx no_wrap: mov ax,dx ;multiply dx by 128. xchg ah,al ror ax,1 mov si,ax add si,offset receive_buf mov ds,base_addr assume ds:nothing call movemem assume ds:code pop ds pop si pop cx call recv_copy push cs pop ds just_discard: mov es,base_addr assume es:ub_seg mov al,epp ;Any more packets left? and al,RPAGE_BITS cmp al,current_page je recv_5 jmp recv_3 recv_5: cmp al,tsa_lsb ;Clearing pav bit (SIDEEFFECT) recv_2: ;Ack the interrupt by turning bit on and off mov al,current_page ;Set first free page pointer mov ffp,al or al,NIC_IE ;set interrupt bit, was off mov ffp,al recv_1: 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 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: ubnic [options] <packet_int_no> <int_no> <base_addr>",CR,LF,'$' public copyright_msg copyright_msg db "Packet driver for the UB PC/NIC, version ",'0'+(majver / 10),'0'+(majver mod 10),".",'0'+version,CR,LF db '$' int_no_name db "Interrupt number ",'$' base_addr_name db "Memory address ",'$' extrn set_recv_isr: near ;enter with si -> argument string, di -> wword to store. ;if there is no number, don't change the number. extrn get_number: near ;enter with si -> argument string, di -> wword 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 base_addr call get_number clc ret public etopen etopen: cli cmp base_addr,-1 ;did they ask for auto-configure? jne no_auto_config mov bx,8000h ;yes, they *could* address it there. auto_config_1: mov es,bx assume es:ub_seg cmp word ptr es:eaddr_rom[0],00h + 0ddh * 256 jne auto_config_2 cmp byte ptr es:eaddr_rom[2],01h je auto_config_3 auto_config_2: add bx,800h ;move up by 32K jnc auto_config_1 ;go if we didn't overflow. sti stc ;say that we couldn't init. ret auto_config_3: mov base_addr,bx ;remember where we found it. mov base_addr+2,0 ;and nuke the rest of the -1. no_auto_config: mov es,base_addr assume es:ub_seg mov reset,80h ;Turn on reset line to tie down NIC mov rmode,0 ;no packets for now mov tmode,0 ;Turn on loopback mov al,epp ;start ffp at epp - eliminates bogus .... and al,07fh mov current_page,al ;... packets if we've been started before mov ffp,al ;Make sure interrupt enable is dead cmp al,tsa_lsb ;Clearing pav bit (SIDEEFFECT) mov tstatus, 0fh ;Clear xmit status bits mov tmask,0 ;No xmit intrs mov rmask,0 ;'Packet okay' only? mov rstatus,0ffh ;Clear receiver status bits movseg ds,es mov di,offset rom_address push ds mov ds,base_addr mov si,offset eaddr_rom repmov EADDR_LEN pop ds mov si,offset rom_address mov cx,EADDR_LEN call set_address ;Since first packet will get sent no matter what we do, let's make it ;something everyone (include me) will ignore ;set length to zero mov tsa_lsb,0ffh ;Get last 8 bits mov tsa_msb,0fh ;and top 4 bits mov reset,0 ;Clear reset - expect packet to go ;Wait for packet to go! etopen_1: mov al,csr and al,TPOK or TXDONE cmp al,TPOK or TXDONE jne etopen_1 mov tstatus,0fh ;clear xmiter status mov tmode,0ah ;Clear loopbk, set parity enable mov csr,0 ;make sure this interrupt was off first mov csr,PAVIntEn ;Page frame available interrupt only mov al,current_page ;Set first free page register ... or al,NIC_IE mov ffp,al ;... and make sure interrupts enabled mov al,epp ;get epp again test al,PAV je etopen_2 cmp al,tsa_lsb ;Try clearing pav bit (SIDEEFFECT) etopen_2: ;enable receiving now ; 1 - accept node id packets, multicasts which match first three ; bytes of node id, and broadcasts mov rmode,1 ; ; Now hook in our interrupt ; call set_recv_isr sti 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, mov dx,offset end_resident clc ret ;if we got an error, stc 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 base_addr mov dx,offset base_addr_name call print_number ret code ends end