[PATCH 02/12] fs_enet: Add MPC5121 FEC support.

Grant Likely grant.likely at secretlab.ca
Fri May 22 01:36:11 EST 2009


2009/5/21 Piotr Zięcik <kosmo at semihalf.com>:
> Thursday 14 May 2009 16:00:33 Grant Likely wrote:
>> > MPC5121 support was added to drivers/net/fs_enet. MPC52xx uses
>> > drivers/net/fec_mpc52xx.c. Do you think that creating one universal
>> > driver from these two is now possible? You said that it should be easy,
>> > however you also said that cache coherency issues makes this imposible.
>>
>> Not impossible.  Hard.
>
> I thought a bit more about merging FEC drivers and I see one problem more.
> Driver fs_enet works with FEC's with own DMA engine and fec_mpc52xx.c uses
> BestComm. Integration of these two drivers will need a DMA abstraction layer
> to keep everything clean. Unfortuanetly BestComm driver does not provide any
> abstraction - it only exports set of functions to deal with specific
> hardware: FEC and PATA.
>
> More #ifdef's will be needed to remove linking with BestComm driver if kernel
> will be compiled without 52xx support and resulting code will not be much
> better than existing one. Especially that new DMA abstraction layer probably
> will be quite complex.

If it looks too ugly, then just fork the driver.

g.

-- 
Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.



More information about the Linuxppc-dev mailing list