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Based on kernel version 3.9. Page generated on 2013-05-02 23:11 EST.

1	The Gianfar Ethernet Driver
2	Sysfs File description
3	
4	Author: Andy Fleming <afleming@freescale.com>
5	Updated: 2005-07-28
6	
7	SYSFS
8	
9	Several of the features of the gianfar driver are controlled
10	through sysfs files.  These are:
11	
12	bd_stash:
13	To stash RX Buffer Descriptors in the L2, echo 'on' or '1' to
14	bd_stash, echo 'off' or '0' to disable
15	
16	rx_stash_len:
17	To stash the first n bytes of the packet in L2, echo the number
18	of bytes to buf_stash_len.  echo 0 to disable.
19	
20	WARNING: You could really screw these up if you set them too low or high!
21	fifo_threshold:
22	To change the number of bytes the controller needs in the
23	fifo before it starts transmission, echo the number of bytes to 
24	fifo_thresh.  Range should be 0-511.
25	
26	fifo_starve:
27	When the FIFO has less than this many bytes during a transmit, it
28	enters starve mode, and increases the priority of TX memory
29	transactions.  To change, echo the number of bytes to
30	fifo_starve.  Range should be 0-511.
31	
32	fifo_starve_off:
33	Once in starve mode, the FIFO remains there until it has this
34	many bytes.  To change, echo the number of bytes to
35	fifo_starve_off.  Range should be 0-511.
36	
37	CHECKSUM OFFLOADING
38	
39	The eTSEC controller (first included in parts from late 2005 like
40	the 8548) has the ability to perform TCP, UDP, and IP checksums
41	in hardware.  The Linux kernel only offloads the TCP and UDP
42	checksums (and always performs the pseudo header checksums), so
43	the driver only supports checksumming for TCP/IP and UDP/IP
44	packets.  Use ethtool to enable or disable this feature for RX
45	and TX.
46	
47	VLAN
48	
49	In order to use VLAN, please consult Linux documentation on
50	configuring VLANs.  The gianfar driver supports hardware insertion and
51	extraction of VLAN headers, but not filtering.  Filtering will be
52	done by the kernel.
53	
54	MULTICASTING
55	
56	The gianfar driver supports using the group hash table on the
57	TSEC (and the extended hash table on the eTSEC) for multicast
58	filtering.  On the eTSEC, the exact-match MAC registers are used
59	before the hash tables.  See Linux documentation on how to join
60	multicast groups.
61	
62	PADDING
63	
64	The gianfar driver supports padding received frames with 2 bytes
65	to align the IP header to a 16-byte boundary, when supported by
66	hardware.
67	
68	ETHTOOL
69	
70	The gianfar driver supports the use of ethtool for many
71	configuration options.  You must run ethtool only on currently
72	open interfaces.  See ethtool documentation for details.
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