| The Gianfar Ethernet Driver | 
 |  | 
 | Author: Andy Fleming <afleming@freescale.com> | 
 | Updated: 2005-07-28 | 
 |  | 
 |  | 
 | CHECKSUM OFFLOADING | 
 |  | 
 | The eTSEC controller (first included in parts from late 2005 like | 
 | the 8548) has the ability to perform TCP, UDP, and IP checksums | 
 | in hardware.  The Linux kernel only offloads the TCP and UDP | 
 | checksums (and always performs the pseudo header checksums), so | 
 | the driver only supports checksumming for TCP/IP and UDP/IP | 
 | packets.  Use ethtool to enable or disable this feature for RX | 
 | and TX. | 
 |  | 
 | VLAN | 
 |  | 
 | In order to use VLAN, please consult Linux documentation on | 
 | configuring VLANs.  The gianfar driver supports hardware insertion and | 
 | extraction of VLAN headers, but not filtering.  Filtering will be | 
 | done by the kernel. | 
 |  | 
 | MULTICASTING | 
 |  | 
 | The gianfar driver supports using the group hash table on the | 
 | TSEC (and the extended hash table on the eTSEC) for multicast | 
 | filtering.  On the eTSEC, the exact-match MAC registers are used | 
 | before the hash tables.  See Linux documentation on how to join | 
 | multicast groups. | 
 |  | 
 | PADDING | 
 |  | 
 | The gianfar driver supports padding received frames with 2 bytes | 
 | to align the IP header to a 16-byte boundary, when supported by | 
 | hardware. | 
 |  | 
 | ETHTOOL | 
 |  | 
 | The gianfar driver supports the use of ethtool for many | 
 | configuration options.  You must run ethtool only on currently | 
 | open interfaces.  See ethtool documentation for details. |