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From: maxime.ripard@free-electrons.com (Maxime Ripard)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 2/2] dmaengine: hdmac: Implement interleaved transfers
Date: Tue, 2 Jun 2015 11:19:51 +0200	[thread overview]
Message-ID: <20150602091951.GV23777@lukather> (raw)
In-Reply-To: <20150601083216.GH25118@odux.rfo.atmel.com>

Hi,

On Mon, Jun 01, 2015 at 10:32:16AM +0200, Ludovic Desroches wrote:
> >  	channel_writel(atchan, CTRLA, 0);
> >  	channel_writel(atchan, CTRLB, 0);
> >  	channel_writel(atchan, DSCR, first->txd.phys);
> > +	channel_writel(atchan, SPIP, ATC_SPIP_HOLE(first->src_hole) |
> > +		       ATC_SPIP_BOUNDARY(first->boundary));
> > +	channel_writel(atchan, DPIP, ATC_DPIP_HOLE(first->dst_hole) |
> > +		       ATC_DPIP_BOUNDARY(first->boundary));
> 
> Can't we get a trivial condition to perform these two writes only if
> needed?

Is that really needed?

My understanding is that the hardware will only take this into account
if we set the ATC_SRC_PIP and ATC_DST_PIP bits anyway, so the check is
already there.

Maxime

-- 
Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
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  reply	other threads:[~2015-06-02  9:19 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-05-27 14:01 [PATCH 0/2] dmaengine: hdmac: Implement interleaved transfers support Maxime Ripard
2015-05-27 14:01 ` [PATCH 1/2] dmaengine: Move icg helpers to global header Maxime Ripard
2015-06-01  8:14   ` Ludovic Desroches
2015-05-27 14:01 ` [PATCH 2/2] dmaengine: hdmac: Implement interleaved transfers Maxime Ripard
2015-06-01  8:32   ` Ludovic Desroches
2015-06-02  9:19     ` Maxime Ripard [this message]
2015-06-12 12:44 ` [PATCH 0/2] dmaengine: hdmac: Implement interleaved transfers support Vinod Koul

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