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From: Grant Likely <grant.likely@secretlab.ca>
Date: Thu, 21 May 2009 09:36:11 -0600
Message-ID: <fa686aa40905210836x73e41651g9995ba813adec139@mail.gmail.com>
Subject: Re: [PATCH 02/12] fs_enet: Add MPC5121 FEC support.
To: =?ISO-8859-2?Q?Piotr_Zi=EAcik?= <kosmo@semihalf.com>
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Cc: Becky Bruce <Becky.Bruce@freescale.com>, Wolfgang Denk <wd@denx.de>,
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2009/5/21 Piotr Zi=EAcik <kosmo@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. =A0Hard.
>
> 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 use=
s
> BestComm. Integration of these two drivers will need a DMA abstraction la=
yer
> 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 ke=
rnel
> will be compiled without 52xx support and resulting code will not be much
> better than existing one. Especially that new DMA abstraction layer proba=
bly
> will be quite complex.

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

g.

--=20
Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.