Re: Marvell SATA driver

[KIYOHARA Takashi <kiyohara%kk.iij4u.or.jp@localhost>]

Hi! Tsutsui-san,


From: Izumi Tsutsui <tsutsui%ceres.dti.ne.jp@localhost>
Date: Sun, 19 Jul 2009 22:25:50 +0900

> > > > I think the option 'PCIIDE_OPTIONS_NODMA' is options for pciide(4).
> > > > the mvsata(4) not use and not include pciide.
> > 
> > > But isn't it better to use cf_flags like pciide(4) rather than
> > > options in config(5) and #ifdefs?
> > 
> > Please specify flags of wd(4) if you do not use DMA for a HDD in which
> > you are.  see man wd(4).
> 
> I'm not asking howto, but design.
> 
> My question is:
> "Is there any particular reason why do you choose a different method
>  (i.e. #ifdef with options) from other ATA drivers to disable DMA?"

The DMA of mvsata is different from pciide and wdc.  However, it becomes
compatible wdc when operating only by PIO.  I think that the size of the
processing of DMA is obstructive in this case.

Thanks,
--
kiyohara