From mboxrd@z Thu Jan  1 00:00:00 1970
From: dwalker@codeaurora.org (Daniel Walker)
Date: Mon, 11 Jan 2010 16:28:53 -0800
Subject: [RFC 16/18] arm: msm: add arch_has_speculative_dfetch()
In-Reply-To: <20100111233356.GJ7925@n2100.arm.linux.org.uk>
References: <1263250057-26692-1-git-send-email-dwalker@codeaurora.org>
	<1263250057-26692-17-git-send-email-dwalker@codeaurora.org>
	<20100111233356.GJ7925@n2100.arm.linux.org.uk>
Message-ID: <1263256133.26505.49.camel@c-dwalke-linux.qualcomm.com>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Mon, 2010-01-11 at 23:33 +0000, Russell King - ARM Linux wrote:
> On Mon, Jan 11, 2010 at 02:47:35PM -0800, Daniel Walker wrote:
> > From: Steve Muckle <smuckle@quicinc.com>
> > 
> > The Scorpion CPU speculatively reads data into the cache. This
> > may occur while a region of memory is being written via DMA, so
> > that region must be invalidated when it is brought under CPU
> > control after the DMA transaction finishes, assuming the DMA
> > was either bidirectional or from the device.
> > 
> > Currently both a clean and invalidate are being done for
> > DMA_BIDIRECTIONAL in dma_unmap_single. Only an invalidate should be
> > required here. There are drivers that currently rely on the clean
> > however so this will be removed when those drivers are updated.
> 
> NAK.  There are patches around (and potentially queued) for the next
> merge window which properly address this.

Do you have any hints on who's doing the development ?

Daniel