;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; ;;
;; Copyright (C) KolibriOS team 2010-2021. All rights reserved. ;;
;; Distributed under terms of the GNU General Public License ;;
;; ;;
;; rhine.asm ;;
;; ;;
;; Ethernet driver for Kolibri OS ;;
;; ;;
;; This driver is based on the via-rhine driver from ;;
;; the etherboot 5.0.6 project. The copyright statement is ;;
;; ;;
;; GNU GENERAL PUBLIC LICENSE ;;
;; Version 2, June 1991 ;;
;; ;;
;; Rewritten in flat assembler by Asper (asper.85@mail.ru) ;;
;; and hidnplayr (hidnplayr@gmail.com) ;;
;; ;;
;; See file COPYING for details ;;
;; ;;
;; ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; TODO: test for RX-overrun
format PE DLL native
entry START
CURRENT_API = 0x0200
COMPATIBLE_API = 0x0100
API_VERSION = (COMPATIBLE_API shl 16) + CURRENT_API
MAX_DEVICES = 16
__DEBUG__ = 1
__DEBUG_LEVEL__ = 2 ; 1 = all, 2 = errors only
TX_RING_SIZE = 32
RX_RING_SIZE = 32
; max time out delay time
W_MAX_TIMEOUT = 0x0FFF
; Size of the in-memory receive ring.
RX_BUF_LEN_IDX = 3 ; 0==8K, 1==16K, 2==32K, 3==64K
; PCI Tuning Parameters
; Threshold is bytes transferred to chip before transmission starts.
TX_FIFO_THRESH = 256 ; In bytes, rounded down to 32 byte units.
; The following settings are log_2(bytes)-4: 0 == 16 bytes .. 6==1024.
RX_FIFO_THRESH = 4 ; Rx buffer level before first PCI transfer.
RX_DMA_BURST = 4 ; Maximum PCI burst, '4' is 256 bytes
TX_DMA_BURST = 4
section '.flat' readable writable executable
include '../proc32.inc'
include '../struct.inc'
include '../macros.inc'
include '../fdo.inc'
include '../netdrv.inc'
;**************************************************************************
; VIA Rhine Register Definitions
;**************************************************************************
byPAR0 = 0x00
byRCR = 0x06
byTCR = 0x07
byCR0 = 0x08
byCR1 = 0x09
byISR0 = 0x0c
byISR1 = 0x0d
byIMR0 = 0x0e
byIMR1 = 0x0f
byMAR0 = 0x10
byMAR1 = 0x11
byMAR2 = 0x12
byMAR3 = 0x13
byMAR4 = 0x14
byMAR5 = 0x15
byMAR6 = 0x16
byMAR7 = 0x17
dwCurrentRxDescAddr = 0x18
dwCurrentTxDescAddr = 0x1c
dwCurrentRDSE0 = 0x20
dwCurrentRDSE1 = 0x24
dwCurrentRDSE2 = 0x28
dwCurrentRDSE3 = 0x2c
dwNextRDSE0 = 0x30
dwNextRDSE1 = 0x34
dwNextRDSE2 = 0x38
dwNextRDSE3 = 0x3c
dwCurrentTDSE0 = 0x40
dwCurrentTDSE1 = 0x44
dwCurrentTDSE2 = 0x48
dwCurrentTDSE3 = 0x4c
dwNextTDSE0 = 0x50
dwNextTDSE1 = 0x54
dwNextTDSE2 = 0x58
dwNextTDSE3 = 0x5c
dwCurrRxDMAPtr = 0x60
dwCurrTxDMAPtr = 0x64
byMPHY = 0x6c
byMIISR = 0x6d
byBCR0 = 0x6e
byBCR1 = 0x6f
byMIICR = 0x70
byMIIAD = 0x71
wMIIDATA = 0x72
byEECSR = 0x74
byTEST = 0x75
byGPIO = 0x76
byCFGA = 0x78
byCFGB = 0x79
byCFGC = 0x7a
byCFGD = 0x7b
wTallyCntMPA = 0x7c
wTallyCntCRC = 0x7d
bySTICKHW = 0x83
byWOLcrClr = 0xA4
byWOLcgClr = 0xA7
byPwrcsrClr = 0xAC
;--------------------- Exioaddr Definitions -------------------------
; Bits in the RCR register
RCR_RRFT2 = 0x80
RCR_RRFT1 = 0x40
RCR_RRFT0 = 0x20
RCR_PROM = 0x10
RCR_AB = 0x08
RCR_AM = 0x04
RCR_AR = 0x02
RCR_SEP = 0x01
; Bits in the TCR register
TCR_RTSF = 0x80
TCR_RTFT1 = 0x40
TCR_RTFT0 = 0x20
TCR_OFSET = 0x08
TCR_LB1 = 0x04 ; loopback[1]
TCR_LB0 = 0x02 ; loopback[0]
; Bits in the CR0 register
CR0_RDMD = 0x40 ; rx descriptor polling demand
CR0_TDMD = 0x20 ; tx descriptor polling demand
CR0_TXON = 0x10
CR0_RXON = 0x08
CR0_STOP = 0x04 ; stop NIC, default = 1
CR0_STRT = 0x02 ; start NIC
CR0_INIT = 0x01 ; start init process
; Bits in the CR1 register
CR1_SFRST = 0x80 ; software reset
CR1_RDMD1 = 0x40 ; RDMD1
CR1_TDMD1 = 0x20 ; TDMD1
CR1_KEYPAG = 0x10 ; turn on par/key
CR1_DPOLL = 0x08 ; disable rx/tx auto polling
CR1_FDX = 0x04 ; full duplex mode
CR1_ETEN = 0x02 ; early tx mode
CR1_EREN = 0x01 ; early rx mode
; Bits in the CR register
CR_RDMD = 0x0040 ; rx descriptor polling demand
CR_TDMD = 0x0020 ; tx descriptor polling demand
CR_TXON = 0x0010
CR_RXON = 0x0008
CR_STOP = 0x0004 ; stop NIC, default = 1
CR_STRT = 0x0002 ; start NIC
CR_INIT = 0x0001 ; start init process
CR_SFRST = 0x8000 ; software reset
CR_RDMD1 = 0x4000 ; RDMD1
CR_TDMD1 = 0x2000 ; TDMD1
CR_KEYPAG = 0x1000 ; turn on par/key
CR_DPOLL = 0x0800 ; disable rx/tx auto polling
CR_FDX = 0x0400 ; full duplex mode
CR_ETEN = 0x0200 ; early tx mode
CR_EREN = 0x0100 ; early rx mode
; Bits in the IMR0 register
IMR0_CNTM = 0x80
IMR0_BEM = 0x40
IMR0_RUM = 0x20
IMR0_TUM = 0x10
IMR0_TXEM = 0x08
IMR0_RXEM = 0x04
IMR0_PTXM = 0x02
IMR0_PRXM = 0x01
; define imrshadow
IMRShadow = 0x5AFF
; Bits in the IMR1 register
IMR1_INITM = 0x80
IMR1_SRCM = 0x40
IMR1_NBFM = 0x10
IMR1_PRAIM = 0x08
IMR1_RES0M = 0x04
IMR1_ETM = 0x02
IMR1_ERM = 0x01
; Bits in the ISR register
ISR_INITI = 0x8000
ISR_SRCI = 0x4000
ISR_ABTI = 0x2000
ISR_NORBF = 0x1000
ISR_PKTRA = 0x0800
ISR_RES0 = 0x0400
ISR_ETI = 0x0200
ISR_ERI = 0x0100
ISR_CNT = 0x0080
ISR_BE = 0x0040
ISR_RU = 0x0020
ISR_TU = 0x0010
ISR_TXE = 0x0008
ISR_RXE = 0x0004
ISR_PTX = 0x0002
ISR_PRX = 0x0001
; Bits in the ISR0 register
ISR0_CNT = 0x80
ISR0_BE = 0x40
ISR0_RU = 0x20
ISR0_TU = 0x10
ISR0_TXE = 0x08
ISR0_RXE = 0x04
ISR0_PTX = 0x02
ISR0_PRX = 0x01
; Bits in the ISR1 register
ISR1_INITI = 0x80
ISR1_SRCI = 0x40
ISR1_NORBF = 0x10
ISR1_PKTRA = 0x08
ISR1_ETI = 0x02
ISR1_ERI = 0x01
; ISR ABNORMAL CONDITION
ISR_ABNORMAL = ISR_BE+ISR_RU+ISR_TU+ISR_CNT+ISR_NORBF+ISR_PKTRA
; Bits in the MIISR register
MIISR_MIIERR = 0x08
MIISR_MRERR = 0x04
MIISR_LNKFL = 0x02
MIISR_SPEED = 0x01
; Bits in the MIICR register
MIICR_MAUTO = 0x80
MIICR_RCMD = 0x40
MIICR_WCMD = 0x20
MIICR_MDPM = 0x10
MIICR_MOUT = 0x08
MIICR_MDO = 0x04
MIICR_MDI = 0x02
MIICR_MDC = 0x01
; Bits in the EECSR register
EECSR_EEPR = 0x80 ; eeprom programmed status, 73h means programmed
EECSR_EMBP = 0x40 ; eeprom embedded programming
EECSR_AUTOLD = 0x20 ; eeprom content reload
EECSR_DPM = 0x10 ; eeprom direct programming
EECSR_CS = 0x08 ; eeprom CS pin
EECSR_SK = 0x04 ; eeprom SK pin
EECSR_DI = 0x02 ; eeprom DI pin
EECSR_DO = 0x01 ; eeprom DO pin
; Bits in the BCR0 register
BCR0_CRFT2 = 0x20
BCR0_CRFT1 = 0x10
BCR0_CRFT0 = 0x08
BCR0_DMAL2 = 0x04
BCR0_DMAL1 = 0x02
BCR0_DMAL0 = 0x01
; Bits in the BCR1 register
BCR1_CTSF = 0x20
BCR1_CTFT1 = 0x10
BCR1_CTFT0 = 0x08
BCR1_POT2 = 0x04
BCR1_POT1 = 0x02
BCR1_POT0 = 0x01
; Bits in the CFGA register
CFGA_EELOAD = 0x80 ; enable eeprom embedded and direct programming
CFGA_JUMPER = 0x40
CFGA_MTGPIO = 0x08
CFGA_T10EN = 0x02
CFGA_AUTO = 0x01
; Bits in the CFGB register
CFGB_PD = 0x80
CFGB_POLEN = 0x02
CFGB_LNKEN = 0x01
; Bits in the CFGC register
CFGC_M10TIO = 0x80
CFGC_M10POL = 0x40
CFGC_PHY1 = 0x20
CFGC_PHY0 = 0x10
CFGC_BTSEL = 0x08
CFGC_BPS2 = 0x04 ; bootrom select[2]
CFGC_BPS1 = 0x02 ; bootrom select[1]
CFGC_BPS0 = 0x01 ; bootrom select[0]
; Bits in the CFGD register
CFGD_GPIOEN = 0x80
CFGD_DIAG = 0x40
CFGD_MAGIC = 0x10
CFGD_RANDOM = 0x08
CFGD_CFDX = 0x04
CFGD_CEREN = 0x02
CFGD_CETEN = 0x01
; Bits in RSR
RSR_RERR = 0x00000001
RSR_CRC = 0x00000002
RSR_FAE = 0x00000004
RSR_FOV = 0x00000008
RSR_LONG = 0x00000010
RSR_RUNT = 0x00000020
RSR_SERR = 0x00000040
RSR_BUFF = 0x00000080
RSR_EDP = 0x00000100
RSR_STP = 0x00000200
RSR_CHN = 0x00000400
RSR_PHY = 0x00000800
RSR_BAR = 0x00001000
RSR_MAR = 0x00002000
RSR_RXOK = 0x00008000
RSR_ABNORMAL = RSR_RERR+RSR_LONG+RSR_RUNT
; Bits in TSR
TSR_NCR0 = 0x00000001
TSR_NCR1 = 0x00000002
TSR_NCR2 = 0x00000004
TSR_NCR3 = 0x00000008
TSR_COLS = 0x00000010
TSR_CDH = 0x00000080
TSR_ABT = 0x00000100
TSR_OWC = 0x00000200
TSR_CRS = 0x00000400
TSR_UDF = 0x00000800
TSR_TBUFF = 0x00001000
TSR_SERR = 0x00002000
TSR_JAB = 0x00004000
TSR_TERR = 0x00008000
TSR_ABNORMAL = TSR_TERR+TSR_OWC+TSR_ABT+TSR_JAB+TSR_CRS
TSR_OWN_BIT = 0x80000000
CB_DELAY_LOOP_WAIT = 10 ; 10ms
; enabled mask value of irq
W_IMR_MASK_VALUE = 0x1BFF ; initial value of IMR
; Ethernet address filter type
PKT_TYPE_DIRECTED = 0x0001 ; obsolete, directed address is always accepted
PKT_TYPE_MULTICAST = 0x0002
PKT_TYPE_ALL_MULTICAST = 0x0004
PKT_TYPE_BROADCAST = 0x0008
PKT_TYPE_PROMISCUOUS = 0x0020
PKT_TYPE_LONG = 0x2000
PKT_TYPE_RUNT = 0x4000
PKT_TYPE_ERROR = 0x8000 ; accept error packets, e.g. CRC error
; Loopback mode
NIC_LB_NONE = 0x00
NIC_LB_INTERNAL = 0x01
NIC_LB_PHY = 0x02 ; MII or Internal-10BaseT loopback
PKT_BUF_SZ = 1514
PCI_REG_MODE3 = 0x53
MODE3_MIION = 0x04 ; in PCI_REG_MOD3 OF PCI space
; VIA Rhine revisions
VT86C100A = 0x00
VTunknown0 = 0x20
VT6102 = 0x40
VT8231 = 0x50 ; Integrated MAC
VT8233 = 0x60 ; Integrated MAC
VT8235 = 0x74 ; Integrated MAC
VT8237 = 0x78 ; Integrated MAC
VTunknown1 = 0x7C
VT6105 = 0x80
VT6105_B0 = 0x83
VT6105L = 0x8A
VT6107 = 0x8C
VTunknown2 = 0x8E
VT6105M = 0x90
; Rx status bits
RX_SBITS_RERR = 1 shl 0
RX_SBITS_CRC_ERROR = 1 shl 1
RX_SBITS_FAE = 1 shl 2
RX_SBITS_FOV = 1 shl 3
RX_SBITS_TOOLONG = 1 shl 4
RX_SBITS_RUNT = 1 shl 5
RX_SBITS_SERR = 1 shl 6
RX_SBITS_BUFF = 1 shl 7
RX_SBITS_EDP = 1 shl 8
RX_SBITS_STP = 1 shl 9
RX_SBITS_CHN = 1 shl 10
RX_SBITS_PHY = 1 shl 11
RX_SBITS_BAR = 1 shl 12
RX_SBITS_MAR = 1 shl 13
RX_SBITS_RESERVED_1 = 1 shl 14
RX_SBITS_RXOK = 1 shl 15
RX_SBITS_FRAME_LENGTH = 0x7FF shl 16
RX_SBITS_RESERVED_2 = 0xF shl 27
RX_SBITS_OWN_BIT = 1 shl 31
; Rx control bits
RX_CBITS_RX_BUF_SIZE = 0x7FF
RX_CBITS_EXTEND_RX_BUF_SIZE = 0xF shl 11
RX_CBITS_RESERVED_1 = 0x1FFFF shl 15
; Tx status bits
TX_SBITS_NCR0 = 1 shl 0
TX_SBITS_NCR1 = 1 shl 1
TX_SBITS_NCR2 = 1 shl 2
TX_SBITS_NCR3 = 1 shl 3
TX_SBITS_COLS = 1 shl 4
TX_SBITS_RESERVED_1 = 1 shl 5
TX_SBITS_CDH = 1 shl 7
TX_SBITS_ABT = 1 shl 8
TX_SBITS_OWC = 1 shl 9
TX_SBITS_CRS = 1 shl 10
TX_SBITS_UDF = 1 shl 11
TX_SBITS_TBUFF = 1 shl 12
TX_SBITS_SERR = 1 shl 13
TX_SBITS_JAB = 1 shl 14
TX_SBITS_TERR = 1 shl 15
TX_SBITS_RESERVED_2 = 0x7FFF shl 16
TX_SBITS_OWN_BIT = 1 shl 31
; Tx control bits
TX_CBITS_TX_BUF_SIZE = 0x7FF
TX_CBITS_EXTEND_TX_BUF_SIZE = 0xF shl 11
TX_CBITS_CHN = 1 shl 15
TX_CBITS_CRC = 1 shl 16
TX_CBITS_RESERVED_1 = 0xF shl 17
TX_CBITS_STP = 1 shl 21
TX_CBITS_EDP = 1 shl 22
TX_CBITS_IC = 1 shl 23
TX_CBITS_RESERVED_2 = 0xFF shl 24
; Offsets to the device registers.
StationAddr = 0x00
RxConfig = 0x06
TxConfig = 0x07
ChipCmd = 0x08
IntrStatus = 0x0C
IntrEnable = 0x0E
MulticastFilter0 = 0x10
MulticastFilter1 = 0x14
RxRingPtr = 0x18
TxRingPtr = 0x1C
GFIFOTest = 0x54
MIIPhyAddr = 0x6C
MIIStatus = 0x6D
PCIBusConfig = 0x6E
MIICmd = 0x70
MIIRegAddr = 0x71
MIIData = 0x72
MACRegEEcsr = 0x74
ConfigA = 0x78
ConfigB = 0x79
ConfigC = 0x7A
ConfigD = 0x7B
RxMissed = 0x7C
RxCRCErrs = 0x7E
MiscCmd = 0x81
StickyHW = 0x83
IntrStatus2 = 0x84
WOLcrClr = 0xA4
WOLcgClr = 0xA7
PwrcsrClr = 0xAC
; Bits in the interrupt status/mask registers.
IntrRxDone = 0x0001
IntrRxErr = 0x0004
IntrRxEmpty = 0x0020
IntrTxDone = 0x0002
IntrTxError = 0x0008
IntrTxUnderrun = 0x0010
IntrPCIErr = 0x0040
IntrStatsMax = 0x0080
IntrRxEarly = 0x0100
IntrRxOverflow = 0x0400
IntrRxDropped = 0x0800
IntrRxNoBuf = 0x1000
IntrTxAborted = 0x2000
IntrLinkChange = 0x4000
IntrRxWakeUp = 0x8000
IntrNormalSummary = 0x0003
IntrAbnormalSummary = 0xC260
IntrTxDescRace = 0x080000 ; mapped from IntrStatus2
IntrTxErrSummary = 0x082218
DEFAULT_INTR = (IntrRxDone or IntrRxErr or IntrRxEmpty or IntrRxOverflow or IntrRxDropped or IntrRxNoBuf)
RX_BUF_LEN = (8192 shl RX_BUF_LEN_IDX)
struct rx_head
status dd ?
control dd ?
buff_addr dd ? ; address
next_desc dd ? ;
buff_addr_virt dd ?
rd 3 ; alignment
ends
struct tx_head
status dd ?
control dd ?
buff_addr dd ? ; address
next_desc dd ? ;
buff_addr_virt dd ?
rd 3 ; alignment
ends
struct device ETH_DEVICE
io_addr dd ?
pci_dev dd ?
pci_bus dd ?
revision db ?
irq_line db ?
chip_vid dw ?
chip_did dw ?
cur_rx dw ?
cur_tx dw ?
last_tx dw ?
rb 0x100 - ($ and 0xff) ; align 256
tx_ring rb sizeof.tx_head*TX_RING_SIZE
rb 0x100 - ($ and 0xff) ; align 256
rx_ring rb sizeof.rx_head*RX_RING_SIZE
ends
;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; ;;
;; proc START ;;
;; ;;
;; (standard driver proc) ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;
proc START c, reason:dword, cmdline:dword
cmp [reason], DRV_ENTRY
jne .fail
DEBUGF 1,"Loading driver\n"
invoke RegService, my_service, service_proc
ret
.fail:
xor eax, eax
ret
endp
;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; ;;
;; proc SERVICE_PROC ;;
;; ;;
;; (standard driver proc) ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;
proc service_proc stdcall, ioctl:dword
mov edx, [ioctl]
mov eax, [edx + IOCTL.io_code]
;------------------------------------------------------
cmp eax, 0 ;SRV_GETVERSION
jne @F
cmp [edx + IOCTL.out_size], 4
jb .fail
mov eax, [edx + IOCTL.output]
mov [eax], dword API_VERSION
xor eax, eax
ret
;------------------------------------------------------
@@:
cmp eax, 1 ;SRV_HOOK
jne .fail
cmp [edx + IOCTL.inp_size], 3 ; Data input must be at least 3 bytes
jb .fail
mov eax, [edx + IOCTL.input]
cmp byte [eax], 1 ; 1 means device number and bus number (pci) are given
jne .fail ; other types aren't supported for this card yet
; check if the device is already listed
mov esi, device_list
mov ecx, [devices]
test ecx, ecx
jz .firstdevice
; mov eax, [edx + IOCTL.input] ; get the pci bus and device numbers
mov ax, [eax+1] ;
.nextdevice:
mov ebx, [esi]
cmp al, byte[ebx + device.pci_bus]
jne @f
cmp ah, byte[ebx + device.pci_dev]
je .find_devicenum ; Device is already loaded, let's find it's device number
@@:
add esi, 4
loop .nextdevice
; This device doesn't have its own eth_device structure yet, lets create one
.firstdevice:
cmp [devices], MAX_DEVICES ; First check if the driver can handle one more card
jae .fail
allocate_and_clear ebx, sizeof.device, .fail ; Allocate the buffer for device structure
; Fill in the direct call addresses into the struct
mov [ebx + device.reset], reset
mov [ebx + device.transmit], transmit
mov [ebx + device.unload], unload
mov [ebx + device.name], my_service
; save the pci bus and device numbers
mov eax, [edx + IOCTL.input]
movzx ecx, byte[eax+1]
mov [ebx + device.pci_bus], ecx
movzx ecx, byte[eax+2]
mov [ebx + device.pci_dev], ecx
; Now, it's time to find the base io address of the PCI device
stdcall PCI_find_io, [ebx + device.pci_bus], [ebx + device.pci_dev]
mov [ebx + device.io_addr], eax
; We've found the io address, find IRQ now
invoke PciRead8, [ebx + device.pci_bus], [ebx + device.pci_dev], PCI_header00.interrupt_line
mov [ebx + device.irq_line], al
DEBUGF 1,"Hooking into device, dev:%x, bus:%x, irq:%x, addr:%x\n",\
[ebx + device.pci_dev]:1,[ebx + device.pci_bus]:1,[ebx + device.irq_line]:1,[ebx + device.io_addr]:4
; Ok, the eth_device structure is ready, let's probe the device
call probe ; this function will output in eax
test eax, eax
jnz .err ; If an error occurred, exit
mov eax, [devices] ; Add the device structure to our device list
mov [device_list+4*eax], ebx ; (IRQ handler uses this list to find device)
inc [devices] ;
mov [ebx + device.type], NET_TYPE_ETH
invoke NetRegDev
cmp eax, -1
je .destroy
ret
; If the device was already loaded, find the device number and return it in eax
.find_devicenum:
DEBUGF 1,"Trying to find device number of already registered device\n"
invoke NetPtrToNum ; This kernel procedure converts a pointer to device struct in ebx
; into a device number in edi
mov eax, edi ; Application wants it in eax instead
DEBUGF 1,"Kernel says: %u\n", eax
ret
; If an error occurred, remove all allocated data and exit (returning -1 in eax)
.destroy:
; todo: reset device into virgin state
.err:
invoke KernelFree, ebx
.fail:
or eax, -1
ret
;------------------------------------------------------
endp
;;/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\;;
;; ;;
;; Actual Hardware dependent code starts here ;;
;; ;;
;;/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\;;
;-------
;
; PROBE
;
;-------
probe:
DEBUGF 1, "Probing\n"
; Make the device a bus master
invoke PciRead32, [ebx + device.pci_bus], [ebx + device.pci_dev], PCI_header00.command
or al, PCI_CMD_MASTER
invoke PciWrite32, [ebx + device.pci_bus], [ebx + device.pci_dev], PCI_header00.command, eax
; get device id
invoke PciRead32, [ebx + device.pci_bus], [ebx + device.pci_dev], PCI_header00.vendor_id
mov dword[ebx + device.chip_vid], eax
mov esi, chiplist
.loop:
cmp dword[esi], eax
je .got_it
add esi, 2*4
cmp dword[esi], 0
jne .loop
DEBUGF 2, "Unknown chip: 0x%x, continuing anyway\n", eax
mov [ebx + device.name], my_service
jmp .done
.got_it:
mov eax, dword[esi+4]
mov [ebx + device.name], eax
DEBUGF 1, "Chip type = %s\n", eax
.done:
; get revision id.
invoke PciRead8, [ebx + device.pci_bus], [ebx + device.pci_dev], PCI_header00.revision_id
mov [ebx + device.revision], al
movzx eax, [ebx + device.revision]
DEBUGF 1, "Card revision = 0x%x\n", eax
; D-Link provided reset code (with comment additions)
cmp al, 0x40
jb .below_x40
mov ax, [ebx + device.chip_did]
DEBUGF 1, "Enabling Sticky Bit Workaround for Chip_id: 0x%x\n", ax
; clear sticky bit before reset & read ethernet address
set_io [ebx + device.io_addr], 0
set_io [ebx + device.io_addr], bySTICKHW
in al, dx
and al, 0xFC
out dx, al
; (bits written are cleared?)
; disable force PME-enable
set_io [ebx + device.io_addr], byWOLcgClr
mov al, 0x80
out dx, al
; disable power-event config bit
mov al, 0xFF
out dx, al
; clear power status (undocumented in vt6102 docs?)
set_io [ebx + device.io_addr], byPwrcsrClr
out dx, al
.below_x40:
; Reset the chip to erase previous misconfiguration.
set_io [ebx + device.io_addr], 0
set_io [ebx + device.io_addr], byCR0
mov ax, CR_SFRST
out dx, ax
; if vt3043 delay after reset
cmp [ebx + device.revision], 0x40
jae @f
mov esi, 200 ; 2000ms
invoke Sleep
@@:
; polling till software reset complete
mov ecx, W_MAX_TIMEOUT
.poll_again:
in ax, dx
test ax, CR_SFRST
jz @f
loop .poll_again
DEBUGF 1, "Soft reset timeout!\n"
@@:
; issue AUTOLoad in EECSR to reload eeprom
set_io [ebx + device.io_addr], byEECSR
mov al, 0x20
out dx, al
; if vt3065 delay after reset
cmp [ebx + device.revision], 0x40
jb .not_vt3065
; delay 10ms to let MAC stable
mov esi, 1 ; 10ms
invoke Sleep
; for 3065D, EEPROM reloaded will cause bit 0 in MAC_REG_CFGA
; turned on. it makes MAC receive magic packet
; automatically. So, we turn it off. (D-Link)
set_io [ebx + device.io_addr], byCFGA
in al, dx
and al, 0xFE
out dx, al
; turn on bit2 in PCI configuration register 0x53 , only for 3065
invoke PciRead8, [ebx + device.pci_bus], [ebx + device.pci_dev], PCI_REG_MODE3
or al, MODE3_MIION
invoke PciWrite8, [ebx + device.pci_bus], [ebx + device.pci_dev], PCI_REG_MODE3, eax
.not_vt3065:
; back off algorithm, disable the right-most 4-bit off CFGD
set_io [ebx + device.io_addr], 0
set_io [ebx + device.io_addr], byCFGD
in al, dx
and al, not (CFGD_RANDOM or CFGD_CFDX or CFGD_CEREN or CFGD_CETEN)
out dx, al
; reload eeprom
call reload_eeprom
; read MAC
call read_mac
; restart MII auto-negotiation
stdcall WriteMII, 0, 1 shl 9, 1
DEBUGF 1, "Analyzing Media type, this may take several seconds"
mov ecx, 5
.read_again:
mov esi, 1
invoke Sleep
stdcall ReadMII, 1
test eax, 0x0020
jnz .read_done
loop .read_again
DEBUGF 1, "timeout!\n"
.read_done:
DEBUGF 1, "OK\n"
if 0
set_io [ebx + device.io_addr], 0
set_io [ebx + device.io_addr], 0x6C
in al, dx
and eax, 0xFF
DEBUGF 1, "MII : Address %x\n", ax
stdcall ReadMII, 1
DEBUGF 1, "status 0x%x\n", ax
stdcall ReadMII, 4
DEBUGF 1, "advertising 0x%x\n", ax
stdcall ReadMII, 5
DEBUGF 1, "link 0x%x\n", ax
end if
; query MII to know LineSpeed, duplex mode
set_io [ebx + device.io_addr], 0
set_io [ebx + device.io_addr], MIIStatus
in al, dx
test al, MIISR_SPEED
jz .100mbps
DEBUGF 1, "Linespeed=10Mbs\n"
jmp @f
.100mbps:
DEBUGF 1, "Linespeed=100Mbs\n"
@@:
call QueryAuto
test eax, 1
jz .halfduplex
DEBUGF 1, "Fullduplex\n"
set_io [ebx + device.io_addr], 0
set_io [ebx + device.io_addr], byCR0
mov ax, CR_FDX
out dx, ax
jmp @f
.halfduplex:
DEBUGF 1, "Halfduplex\n"
@@:
; set MII 10 FULL ON, only apply in vt3043
cmp [ebx + device.chip_did], 0x3043
jne @f
stdcall WriteMII, 0x17, 1 shl 1, 1
@@:
; turn on MII link change
set_io [ebx + device.io_addr], 0
set_io [ebx + device.io_addr], byMIICR
in al, dx
and al, 0x7F
out dx, al
push eax
call MIIDelay
set_io [ebx + device.io_addr], byMIIAD
mov al, 0x41
out dx, al
call MIIDelay
pop eax
or al, 0x80
set_io [ebx + device.io_addr], byMIICR
out dx, al
;**************************************************************************;
;* ETH_RESET - Reset adapter *;
;**************************************************************************;
reset:
DEBUGF 1, "reset\n"
; attach int handler
movzx eax, [ebx + device.irq_line]
DEBUGF 1,"Attaching int handler to irq %x\n", eax:1
invoke AttachIntHandler, eax, int_handler, ebx
test eax, eax
jz .err
; Soft reset the chip.
set_io [ebx + device.io_addr], 0
set_io [ebx + device.io_addr], byCR0
mov ax, CR_SFRST
out dx, ax
call MIIDelay
; Initialize rings
call init_ring
test eax, eax
jnz .err
; Set Multicast
call set_rx_mode
; set TCR RCR threshold to store and forward
set_io [ebx + device.io_addr], 0
set_io [ebx + device.io_addr], byBCR0
mov al, 0x3E
out dx, al
set_io [ebx + device.io_addr], byBCR1
mov al, 0x38
out dx, al
set_io [ebx + device.io_addr], byRCR
mov al, 0x2C
out dx, al
set_io [ebx + device.io_addr], byTCR
mov al, 0x60
out dx, al
; Set Fulldupex
call QueryAuto
test eax, eax ; full duplex?
jz @f
set_io [ebx + device.io_addr], 0
set_io [ebx + device.io_addr], byCFGD
mov al, CFGD_CFDX
out dx, al
set_io [ebx + device.io_addr], byCR0
mov ax, CR_FDX
out dx, ax
@@:
; ENABLE interrupts
set_io [ebx + device.io_addr], 0
set_io [ebx + device.io_addr], byIMR0
mov ax, DEFAULT_INTR
out dx, ax
; KICK NIC to WORK
set_io [ebx + device.io_addr], byCR0
in ax, dx
and ax, not CR_STOP
or ax, CR_STRT or CR_TXON or CR_RXON or CR_DPOLL
out dx, ax
; Set the mtu, kernel will be able to send now
mov [ebx + device.mtu], 1514
; Set link state to unknown
mov [ebx + device.state], ETH_LINK_UNKNOWN
; say reset was successful
xor eax, eax
ret
.err:
DEBUGF 2,"Error!\n"
or eax, -1
ret
align 4
unload:
call reset
push eax edx
DEBUGF 1, "rhine disable\n"
; Switch to loopback mode to avoid hardware races.
set_io [ebx + device.io_addr], 0
set_io [ebx + device.io_addr], byTCR
mov al, 0x61
out dx, al
; Stop the chip's Tx and Rx processes.
set_io [ebx + device.io_addr], byCR0
mov ax, CR_STOP
out dx, ax
pop edx eax
ret
align 4
reload_eeprom:
DEBUGF 1, "Reload eeprom\n"
set_io [ebx + device.io_addr], 0
set_io [ebx + device.io_addr], byEECSR
mov al, 0x20
out dx, al
; Typically 2 cycles to reload.
mov ecx, 150
.reload:
in al, dx
test al, 0x20
jz @f
loop .reload
DEBUGF 2, "Reload eeprom: timeout!\n"
@@:
ret
; Initialize the Rx and Tx rings, along with various 'dev' bits.
align 4
init_ring:
DEBUGF 1, "Init ring\n"
lea edi, [ebx + device.rx_ring]
mov eax, edi
invoke GetPhysAddr
mov esi, eax
push esi
mov ecx, RX_RING_SIZE
.rx_init:
add esi, sizeof.rx_head
mov [edi + rx_head.status], RX_SBITS_OWN_BIT
mov [edi + rx_head.control], PKT_BUF_SZ
push ecx
invoke NetAlloc, PKT_BUF_SZ+NET_BUFF.data
pop ecx
test eax, eax
jz .out_of_mem
mov [edi + rx_head.buff_addr_virt], eax
invoke GetPhysAddr
add eax, NET_BUFF.data
mov [edi + rx_head.buff_addr], eax ; buffer ptr
mov [edi + rx_head.next_desc], esi ; next head
add edi, sizeof.rx_head
dec ecx
jnz .rx_init
pop [edi - sizeof.rx_head + rx_head.next_desc] ; Mark the last entry as wrapping the ring.
lea edi, [ebx + device.tx_ring]
mov eax, edi
invoke GetPhysAddr
mov esi, eax
push esi
mov ecx, TX_RING_SIZE
.tx_init:
add esi, sizeof.tx_head
mov [edi + tx_head.status], 0
mov [edi + tx_head.control], 0x00E08000
mov [edi + tx_head.buff_addr], 0
mov [edi + tx_head.next_desc], esi
mov [edi + tx_head.buff_addr_virt], 0
add edi, sizeof.tx_head
dec ecx
jnz .tx_init
pop [edi - sizeof.tx_head + tx_head.next_desc] ; Mark the last entry as wrapping the ring.
; write Descriptors to MAC
lea eax, [ebx + device.rx_ring]
invoke GetPhysAddr
set_io [ebx + device.io_addr], 0
set_io [ebx + device.io_addr], dwCurrentRxDescAddr
out dx, eax
lea eax, [ebx + device.tx_ring]
invoke GetPhysAddr
set_io [ebx + device.io_addr], dwCurrentTxDescAddr
out dx, eax
xor eax, eax
mov [ebx + device.cur_rx], ax
mov [ebx + device.cur_tx], ax
mov [ebx + device.last_tx], ax
xor eax, eax
ret
.out_of_mem:
add esp, 4
or eax, -1
ret
align 4
QueryAuto:
DEBUGF 1, "Query Auto\n"
push ecx
stdcall ReadMII, 0x04 ; advertised
mov ecx, eax
stdcall ReadMII, 0x05
and ecx, eax
xor eax, eax
test ecx, 0x100
jnz .one
and ecx, 0x1C0
cmp ecx, 0x40
jne .zero
.one:
inc eax
DEBUGF 1, "AutoNego OK!\n"
.zero:
pop ecx
ret
proc ReadMII stdcall, byMIIIndex:dword
; DEBUGF 1, "ReadMII Index=%x\n", [byMIIIndex]
push esi ebx ecx edx
set_io [ebx + device.io_addr], 0
set_io [ebx + device.io_addr], byMIIAD
in al, dx
mov bl, al
set_io [ebx + device.io_addr], byMIICR
in al, dx
mov bh, al
and al, 0x7F
out dx, al
call MIIDelay
mov al, byte [byMIIIndex]
set_io [ebx + device.io_addr], byMIIAD
out dx, al
call MIIDelay
set_io [ebx + device.io_addr], byMIICR
in al, dx
or al, 0x40
out dx, al
mov ecx, 200
.read_again:
in al, dx
test al, 0x40
jz @f
mov esi, 10
invoke Sleep
dec ecx
jnz .read_again
DEBUGF 2, "ReadMII: timeout!\n"
@@:
call MIIDelay
set_io [ebx + device.io_addr], byMIIAD
in ax, dx
push eax
mov ax, bx
set_io [ebx + device.io_addr], byMIIAD
out dx, al
shr ax, 8
set_io [ebx + device.io_addr], byMIICR
out dx, al
call MIIDelay
pop eax
and eax, 0xFFFF
rol ax, 8
pop edx ecx ebx esi
ret
endp
proc WriteMII stdcall, byMIISetByte:dword, byMIISetBit:dword, byMIIOP:dword
; DEBUGF 1, "WriteMII SetByte=%x SetBit=%x OP=%x\n", [byMIISetByte], [byMIISetBit], [byMIIOP]
push ebx eax ecx edx
set_io [ebx + device.io_addr], 0
set_io [ebx + device.io_addr], byMIIAD
in al, dx
mov bl, al
set_io [ebx + device.io_addr], byMIICR
in al, dx
mov bh, al
and al, 0x7F
out dx, al
call MIIDelay
mov al, byte [byMIISetByte]
set_io [ebx + device.io_addr], byMIIAD
out dx, al
call MIIDelay
set_io [ebx + device.io_addr], byMIICR
in al, dx
or al, 0x40
out dx, al
mov ecx, 200
.read_again0:
in al, dx
test al, 0x40
jz .done
mov esi, 10
invoke Sleep
dec ecx
jnz .read_again0
DEBUGF 2, "WriteMII: timeout (1)\n"
.done:
call MIIDelay
set_io [ebx + device.io_addr], wMIIDATA
in ax, dx
mov ecx, [byMIISetBit]
rol cx, 8
cmp byte [byMIIOP], 0
jne @f
not ecx
and ax, cx
jmp .end_mascarad
@@:
or ax, cx
.end_mascarad:
set_io [ebx + device.io_addr], wMIIDATA
out dx, ax
call MIIDelay
set_io [ebx + device.io_addr], byMIICR
in al, dx
or al, 0x20
out dx, al
mov ecx, 200
.read_again1:
in al, dx
test al, 0x20
jz @f
mov esi, 10
invoke Sleep
dec ecx
jnz .read_again1
DEBUGF 2, "WriteMII timeout (2)\n"
@@:
call MIIDelay
mov ax, bx
and al, 0x7F
set_io [ebx + device.io_addr], byMIIAD
out dx, al
shr ax, 8
set_io [ebx + device.io_addr], byMIICR
out dx, al
call MIIDelay
pop edx ecx eax ebx
ret
endp
align 4
MIIDelay:
mov ecx, 0x7FFF
@@:
in al, 0x61
in al, 0x61
in al, 0x61
in al, 0x61
loop @b
ret
align 4
set_rx_mode:
DEBUGF 1, "Set RX mode\n"
; ! IFF_PROMISC
mov eax, 0xffffffff
set_io [ebx + device.io_addr], 0
set_io [ebx + device.io_addr], byMAR0
out dx, eax
set_io [ebx + device.io_addr], byMAR4
out dx, eax
set_io [ebx + device.io_addr], byRCR
mov al, 0x6C ; thresh or rx_mode
out dx, al
ret
; Beware of PCI posted writes
macro IOSYNC
{
set_io [ebx + device.io_addr], StationAddr
in al, dx
}
align 4
read_mac:
lea edi, [ebx + device.mac]
set_io [ebx + device.io_addr], 0
set_io [ebx + device.io_addr], byPAR0
mov ecx, 6
.next:
in al, dx
stosb
inc edx
dec ecx
jnz .next
DEBUGF 1,"MAC = %x-%x-%x-%x-%x-%x\n", \
[ebx + device.mac+0]:2,[ebx + device.mac+1]:2,[ebx + device.mac+2]:2,[ebx + device.mac+3]:2,[ebx + device.mac+4]:2,[ebx + device.mac+5]:2
ret
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; ;;
;; Transmit ;;
;; ;;
;; In: buffer pointer in [esp+4] ;;
;; pointer to device structure in ebx ;;
;; Out: eax = 0 on success ;;
;; ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
align 16
proc transmit stdcall bufferptr
spin_lock_irqsave
mov esi, [bufferptr]
DEBUGF 1,"Transmitting packet, buffer:%x, size:%u\n", [bufferptr], [esi + NET_BUFF.length]
lea eax, [esi + NET_BUFF.data]
DEBUGF 1,"To: %x-%x-%x-%x-%x-%x From: %x-%x-%x-%x-%x-%x Type:%x%x\n",\
[eax+00]:2,[eax+01]:2,[eax+02]:2,[eax+03]:2,[eax+04]:2,[eax+05]:2,\
[eax+06]:2,[eax+07]:2,[eax+08]:2,[eax+09]:2,[eax+10]:2,[eax+11]:2,\
[eax+13]:2,[eax+12]:2
cmp [esi + NET_BUFF.length], 1514
ja .error
cmp [esi + NET_BUFF.length], 60
jb .error
; Program the descriptor
movzx eax, [ebx + device.cur_tx]
mov ecx, sizeof.tx_head
mul ecx
lea edi, [ebx + device.tx_ring]
add edi, eax
cmp [edi + tx_head.buff_addr_virt], 0
jne .overrun
mov eax, esi
mov [edi + tx_head.buff_addr_virt], eax
add eax, [eax + NET_BUFF.offset]
invoke GetPhysAddr
mov [edi + tx_head.buff_addr], eax
mov ecx, [esi + NET_BUFF.length]
and ecx, TX_CBITS_TX_BUF_SIZE
or ecx, 0x00E08000
mov [edi + tx_head.control], ecx
or [edi + tx_head.status], TX_SBITS_OWN_BIT
set_io [ebx + device.io_addr], 0
set_io [ebx + device.io_addr], byCR1
in al, dx
or al, CR1_TDMD1
out dx, al
inc [ebx + device.cur_tx]
and [ebx + device.cur_tx], TX_RING_SIZE-1
;outw(IMRShadow,byIMR0); ;
; Update stats
inc [ebx + device.packets_tx]
mov ecx, [esi + NET_BUFF.length]
add dword [ebx + device.bytes_tx], ecx
adc dword [ebx + device.bytes_tx + 4], 0
spin_unlock_irqrestore
xor eax, eax
ret
.error:
DEBUGF 2, "TX packet error\n"
inc [ebx + device.packets_tx_err]
invoke NetFree, [bufferptr]
spin_unlock_irqrestore
or eax, -1
ret
.overrun:
DEBUGF 2, "TX overrun\n"
inc [ebx + device.packets_tx_ovr]
invoke NetFree, [bufferptr]
spin_unlock_irqrestore
or eax, -1
ret
endp
;;;;;;;;;;;;;;;;;;;;;;;
;; ;;
;; Interrupt handler ;;
;; ;;
;;;;;;;;;;;;;;;;;;;;;;;
align 16
int_handler:
push ebx esi edi
mov ebx, [esp+4*4]
DEBUGF 1,"INT for 0x%x\n", ebx
set_io [ebx + device.io_addr], 0
set_io [ebx + device.io_addr], IntrStatus
in ax, dx
test ax, ax
jz .nothing
out dx, ax ; ACK interrupt
DEBUGF 1, "Status=0x%x\n", ax
push ax
test ax, IntrRxDone
jz .not_RX
push ebx
.more_RX:
pop ebx
; Get the current descriptor pointer
movzx eax, [ebx + device.cur_rx]
mov ecx, sizeof.rx_head
mul ecx
lea edi, [ebx + device.rx_ring]
add edi, eax
; Check it's status
test [edi + rx_head.status], RX_SBITS_OWN_BIT
jnz .not_RX
DEBUGF 1, "Packet status = 0x%x\n", [edi + rx_head.status]
; TODO: check error bits
; get length
mov ecx, [edi + rx_head.status]
and ecx, RX_SBITS_FRAME_LENGTH
shr ecx, 16
sub ecx, 4 ; We dont want CRC
; Update stats
add dword [ebx + device.bytes_rx], ecx
adc dword [ebx + device.bytes_rx + 4], 0
inc [ebx + device.packets_rx]
; Push packet pointer, kernel will need it..
push ebx
push .more_RX ; return ptr
mov eax, [edi + rx_head.buff_addr_virt]
push eax
mov [eax + NET_BUFF.length], ecx
mov [eax + NET_BUFF.device], ebx
mov [eax + NET_BUFF.offset], NET_BUFF.data
; reset the RX descriptor
push edi
invoke NetAlloc, PKT_BUF_SZ+NET_BUFF.data
pop edi
mov [edi + rx_head.buff_addr_virt], eax
invoke GetPhysAddr
add eax, NET_BUFF.data
mov [edi + rx_head.buff_addr], eax
mov [edi + rx_head.status], RX_SBITS_OWN_BIT
; Use next descriptor next time
inc [ebx + device.cur_rx]
and [ebx + device.cur_rx], RX_RING_SIZE - 1
; At last, send packet to kernel
jmp [EthInput]
.not_RX:
pop ax
test ax, IntrTxDone
jz .not_TX
.loop_tx:
movzx eax, [ebx + device.last_tx]
mov ecx, sizeof.tx_head
mul ecx
lea edi, [ebx + device.tx_ring]
add edi, eax
test [edi + tx_head.status], TX_SBITS_OWN_BIT
jnz .not_TX
cmp [edi + tx_head.buff_addr_virt], 0
je .not_TX
DEBUGF 1,"Freeing buffer 0x%x\n", [edi + tx_head.buff_addr_virt]
push [edi + tx_head.buff_addr_virt]
mov [edi + tx_head.buff_addr_virt], 0
invoke NetFree
inc [ebx + device.last_tx]
and [ebx + device.last_tx], TX_RING_SIZE - 1
jmp .loop_tx
.not_TX:
; On Rhine-II, Bit 3 indicates Tx descriptor write-back race.
if 0
cmp [ebx + device.chip_id], 0x3065
jne @f
push ax
xor eax, eax
set_io [ebx + device.io_addr], IntrStatus2
in al, dx
shl eax, 16
pop ax
@@:
end if
if 0
; Acknowledge all of the current interrupt sources ASAP.
xor ecx, ecx
test eax, IntrTxDescRace
jz @f
set_io [ebx + device.io_addr], 0
set_io [ebx + device.io_addr], IntrStatus2
push ax
mov al, 0x08
out dx, al
pop ax
@@:
set_io [ebx + device.io_addr], 0
set_io [ebx + device.io_addr], IntrStatus
out dx, ax
IOSYNC
end if
pop edi esi ebx
xor eax, eax
inc eax
ret
.nothing:
pop edi esi ebx
xor eax, eax
ret
; End of code
data fixups
end data
include '../peimport.inc'
my_service db 'RHINE',0 ; max 16 chars including zero
chiplist:
dd 0x30431106, rhine_3043;, RHINE_IOTYPE, RHINE_I_IOSIZE, CanHaveMII or ReqTxAlign or HasV1TxStat
dd 0x61001106, rhine_6100;, RHINE_IOTYPE, RHINE_I_IOSIZE, CanHaveMII or ReqTxAlign or HasV1TxStat
dd 0x30651106, rhine_6102;, RHINE_IOTYPE, RHINEII_IOSIZE, CanHaveMII or HasWOL
dd 0x31061106, rhine_6105;, RHINE_IOTYPE, RHINEII_IOSIZE, CanHaveMII or HasWOL
; Duplicate entry, with 'M' features enabled.
; dd 0x31061106, rhine_6105;, RHINE_IOTYPE, RHINEII_IOSIZE, CanHaveMII or HasWOL or HasIPChecksum or HasVLAN
dd 0x30531106, rhine_3053;, RHINE_IOTYPE, RHINEII_IOSIZE, CanHaveMII or HasWOL
dd 0
rhine_3043 db "VIA VT3043 Rhine", 0
rhine_6100 db "VIA VT86C100A Rhine", 0
rhine_6102 db "VIA VT6102 Rhine-II", 0
rhine_6105 db "VIA VT6105LOM Rhine-III (3106)", 0
rhine_3053 db "VIA VT6105M Rhine-III (3053 prototype)", 0
include_debug_strings ; All data which FDO uses will be included here
align 4
devices dd 0
device_list rd MAX_DEVICES ; This list contains all pointers to device structures the driver is handling