return 0 instead of EINVAL. In this case, there will only be one media
type, and the upper-level if_media code will ensure that the user is
setting to that type.
This matches changes Jason made a while back to sys/dev/ic/lance.c
directly, call the function pointer (*if_input)(ifp, m). The input routine
expects the packet header to be at the head of the packet, and will adjust
as necessary. Privatize the layer 2 input and output routines, allowing
*_ifattach() to set them up as appropriate.
- "out of resource" errors cause receive buffer chain corruption
- resets can confuse the interrupt handler
- multi-cast setup causes receive buffer chain corruption
- shared memory setup incomplete
* Enhance effiency by avoiding unnecessary shared memory access,
improved handling of receive frame & buffer descriptors, and
introducing an `asynchronous' option when issuing 82586 commands.
* Exclusively use offsets relative to the bus handle representing the shared
memory area to formulate accesses to the chip's data-structures. The
front-ends provide glue functions that cater to the chip's endian-
sensitivity, to perform the actual device access (note: single-byte
accesses are done here using `bus_space_{read,write}_1()').
This concludes the transformation into a bus-independent driver module.
a command to the 82586 for every frame to be transmitted. Instead, a
single command sets off the execution of a chain of commands consisting
of alternate XMITs and NO-OPs, where the link fields in the NO-OPs are
set to loop back onto themselves until the next XMIT is ready to go.
This trick found on a Linux WEB page.
All this induces reasonable transmission performance in my old multibus
adapter. The receiver performance is still abysmal..