From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marek Vasut <marex@denx.de>
To: Huang Shijie <b32955@freescale.com>
Subject: Re: [PATCH] dma: add new DMA control commands
Date: Thu, 18 Oct 2012 12:51:14 +0200
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Dear Huang Shijie,

> =E4=BA=8E 2012=E5=B9=B410=E6=9C=8818=E6=97=A5 16:49, Marek Vasut =E5=86=
=99=E9=81=93:
> > Dear Huang Shijie,
> >=20
> >> =E4=BA=8E 2012=E5=B9=B410=E6=9C=8818=E6=97=A5 16:16, Marek Vasut =E5=
=86=99=E9=81=93:
> >>> So we can't stream data from the chip? About time to adjust the MTD
> >>> framework to allow that. Maybe implement a command queue?
> >>=20
> >> IMHO, it's not possible. Because the READ-PAGE(00h-30h) command needs =
to
> >> check the busy status
> >> which means we have to stop in the middle, so we can not chain the all
> >> the read-pages DMA commands.
> >=20
> > Can the DMA not branch?
>=20
> it's too complicated to the MTD layer, as well as the gpmi driver.

Can you please elaborate ?

Best regards,
Marek Vasut