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Based on kernel version 3.13. Page generated on 2014-01-20 22:03 EST.

1	    Originally,   this  driver  was    written  for the  Digital   Equipment
2	    Corporation series of EtherWORKS Ethernet cards:
3	
4	        DE425 TP/COAX EISA
5		DE434 TP PCI
6		DE435 TP/COAX/AUI PCI
7		DE450 TP/COAX/AUI PCI
8		DE500 10/100 PCI Fasternet
9	
10	    but it  will  now attempt  to  support all  cards which   conform to the
11	    Digital Semiconductor   SROM   Specification.    The  driver   currently
12	    recognises the following chips:
13	
14	        DC21040  (no SROM) 
15		DC21041[A]  
16		DC21140[A] 
17		DC21142 
18		DC21143 
19	
20	    So far the driver is known to work with the following cards:
21	
22	        KINGSTON
23		Linksys
24		ZNYX342
25		SMC8432
26		SMC9332 (w/new SROM)
27		ZNYX31[45]
28		ZNYX346 10/100 4 port (can act as a 10/100 bridge!) 
29	
30	    The driver has been tested on a relatively busy network using the DE425,
31	    DE434, DE435 and DE500 cards and benchmarked with 'ttcp': it transferred
32	    16M of data to a DECstation 5000/200 as follows:
33	
34	                TCP           UDP
35	             TX     RX     TX     RX
36	    DE425   1030k  997k   1170k  1128k
37	    DE434   1063k  995k   1170k  1125k
38	    DE435   1063k  995k   1170k  1125k
39	    DE500   1063k  998k   1170k  1125k  in 10Mb/s mode
40	
41	    All  values are typical (in   kBytes/sec) from a  sample  of 4 for  each
42	    measurement. Their error is +/-20k on a quiet (private) network and also
43	    depend on what load the CPU has.
44	
45	    =========================================================================
46	
47	    The ability to load this  driver as a loadable  module has been included
48	    and used extensively  during the driver development  (to save those long
49	    reboot sequences).  Loadable module support  under PCI and EISA has been
50	    achieved by letting the driver autoprobe as if it were compiled into the
51	    kernel. Do make sure  you're not sharing  interrupts with anything  that
52	    cannot accommodate  interrupt  sharing!
53	
54	    To utilise this ability, you have to do 8 things:
55	
56	    0) have a copy of the loadable modules code installed on your system.
57	    1) copy de4x5.c from the  /linux/drivers/net directory to your favourite
58	    temporary directory.
59	    2) for fixed  autoprobes (not  recommended),  edit the source code  near
60	    line 5594 to reflect the I/O address  you're using, or assign these when
61	    loading by:
62	
63	                   insmod de4x5 io=0xghh           where g = bus number
64			                                        hh = device number   
65	
66	       NB: autoprobing for modules is now supported by default. You may just
67	           use:
68	
69	                   insmod de4x5
70	
71	           to load all available boards. For a specific board, still use
72		   the 'io=?' above.
73	    3) compile  de4x5.c, but include -DMODULE in  the command line to ensure
74	    that the correct bits are compiled (see end of source code).
75	    4) if you are wanting to add a new  card, goto 5. Otherwise, recompile a
76	    kernel with the de4x5 configuration turned off and reboot.
77	    5) insmod de4x5 [io=0xghh]
78	    6) run the net startup bits for your new eth?? interface(s) manually 
79	    (usually /etc/rc.inet[12] at boot time). 
80	    7) enjoy!
81	
82	    To unload a module, turn off the associated interface(s) 
83	    'ifconfig eth?? down' then 'rmmod de4x5'.
84	
85	    Automedia detection is included so that in  principle you can disconnect
86	    from, e.g.  TP, reconnect  to BNC  and  things will still work  (after a
87	    pause whilst the   driver figures out   where its media went).  My tests
88	    using ping showed that it appears to work....
89	
90	    By  default,  the driver will  now   autodetect any  DECchip based card.
91	    Should you have a need to restrict the driver to DIGITAL only cards, you
92	    can compile with a  DEC_ONLY define, or if  loading as a module, use the
93	    'dec_only=1'  parameter. 
94	
95	    I've changed the timing routines to  use the kernel timer and scheduling
96	    functions  so that the  hangs  and other assorted problems that occurred
97	    while autosensing the  media  should be gone.  A  bonus  for the DC21040
98	    auto  media sense algorithm is  that it can now  use one that is more in
99	    line with the  rest (the DC21040  chip doesn't  have a hardware  timer).
100	    The downside is the 1 'jiffies' (10ms) resolution.
101	
102	    IEEE 802.3u MII interface code has  been added in anticipation that some
103	    products may use it in the future.
104	
105	    The SMC9332 card  has a non-compliant SROM  which needs fixing -  I have
106	    patched this  driver to detect it  because the SROM format used complies
107	    to a previous DEC-STD format.
108	
109	    I have removed the buffer copies needed for receive on Intels.  I cannot
110	    remove them for   Alphas since  the  Tulip hardware   only does longword
111	    aligned  DMA transfers  and  the  Alphas get   alignment traps with  non
112	    longword aligned data copies (which makes them really slow). No comment.
113	
114	    I  have added SROM decoding  routines to make this  driver work with any
115	    card that  supports the Digital  Semiconductor SROM spec. This will help
116	    all  cards running the dc2114x  series chips in particular.  Cards using
117	    the dc2104x  chips should run correctly with  the basic  driver.  I'm in
118	    debt to <mjacob@feral.com> for the  testing and feedback that helped get
119	    this feature working.  So far we have  tested KINGSTON, SMC8432, SMC9332
120	    (with the latest SROM complying  with the SROM spec  V3: their first was
121	    broken), ZNYX342  and  LinkSys. ZNYX314 (dual  21041  MAC) and  ZNYX 315
122	    (quad 21041 MAC)  cards also  appear  to work despite their  incorrectly
123	    wired IRQs.
124	
125	    I have added a temporary fix for interrupt problems when some SCSI cards
126	    share the same interrupt as the DECchip based  cards. The problem occurs
127	    because  the SCSI card wants to  grab the interrupt  as a fast interrupt
128	    (runs the   service routine with interrupts turned   off) vs.  this card
129	    which really needs to run the service routine with interrupts turned on.
130	    This driver will  now   add the interrupt service   routine  as  a  fast
131	    interrupt if it   is bounced from the   slow interrupt.  THIS IS NOT   A
132	    RECOMMENDED WAY TO RUN THE DRIVER  and has been done  for a limited time
133	    until  people   sort  out their  compatibility    issues and the  kernel
134	    interrupt  service code  is  fixed.   YOU  SHOULD SEPARATE OUT  THE FAST
135	    INTERRUPT CARDS FROM THE SLOW INTERRUPT CARDS to ensure that they do not
136	    run on the same interrupt. PCMCIA/CardBus is another can of worms...
137	
138	    Finally, I think  I have really  fixed  the module  loading problem with
139	    more than one DECchip based  card.  As a  side effect, I don't mess with
140	    the  device structure any  more which means that  if more than 1 card in
141	    2.0.x is    installed (4  in   2.1.x),  the  user   will have   to  edit
142	    linux/drivers/net/Space.c  to make room for  them. Hence, module loading
143	    is  the preferred way to use   this driver, since  it  doesn't have this
144	    limitation.
145	
146	    Where SROM media  detection is used and  full duplex is specified in the
147	    SROM,  the feature is  ignored unless  lp->params.fdx  is set at compile
148	    time  OR during  a   module load  (insmod  de4x5   args='eth??:fdx' [see
149	    below]).  This is because there  is no way  to automatically detect full
150	    duplex   links  except through   autonegotiation.    When I  include the
151	    autonegotiation feature in  the SROM autoconf  code, this detection will
152	    occur automatically for that case.
153	
154	    Command line  arguments are  now allowed, similar to  passing  arguments
155	    through LILO. This will allow a per adapter board set  up of full duplex
156	    and media. The only lexical constraints are:  the board name (dev->name)
157	    appears in  the list before its parameters.  The list of parameters ends
158	    either at the end of the parameter list or with another board name.  The
159	    following parameters are allowed:
160	
161	            fdx        for full duplex
162		    autosense  to set the media/speed; with the following 
163		               sub-parameters:
164			       TP, TP_NW, BNC, AUI, BNC_AUI, 100Mb, 10Mb, AUTO
165	
166	    Case sensitivity is important  for  the sub-parameters. They *must*   be
167	    upper case. Examples:
168	
169	        insmod de4x5 args='eth1:fdx autosense=BNC eth0:autosense=100Mb'.
170	
171	    For a compiled in driver, in linux/drivers/net/CONFIG, place e.g.
172		DE4X5_OPTS = -DDE4X5_PARM='"eth0:fdx autosense=AUI eth2:autosense=TP"' 
173	
174	    Yes,  I know full duplex  isn't permissible on BNC  or AUI; they're just
175	    examples. By default, full duplex is turned  off and AUTO is the default
176	    autosense setting. In  reality, I expect only the  full duplex option to
177	    be used. Note the use of single quotes in the two examples above and the
178	    lack of commas to separate items.
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