From: Arnd Bergmann <arnd@arndb.de>
To: linuxppc-dev@lists.ozlabs.org
Cc: Scott Wood <scottwood@freescale.com>,
Chris Pringle <chris.pringle@oxtel.com>,
linux-kernel@vger.kernel.org
Subject: Re: PowerPC PCI DMA issues (prefetch/coherency?)
Date: Tue, 16 Jun 2009 19:43:38 +0200 [thread overview]
Message-ID: <200906161943.38764.arnd@arndb.de> (raw)
In-Reply-To: <4A37D073.6020802@freescale.com>
On Tuesday 16 June 2009, Scott Wood wrote:
> Chris Pringle wrote:
> > Ah right - that would explain what we're seeing then... Doh. Thought I
> > might have been onto something then. Is there any way to force a cache
> > flush? That'd at least prove it was a caching issue if it resolved the
> > problem.
>
> You could enable CONFIG_NOT_COHERENT_CACHE.
If the whole system is noncoherent, that is the right solution. If the
device is the only one, you can also use dma_alloc_noncoherent() and
flush explicitly with dma_cache_sync().
Arnd <><
next prev parent reply other threads:[~2009-06-16 17:44 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-06-16 13:58 PowerPC PCI DMA issues (prefetch/coherency?) Chris Pringle
2009-06-16 14:16 ` Michael S. Zick
2009-06-16 14:59 ` Hu Gang
2009-06-16 16:21 ` Scott Wood
2009-06-16 16:34 ` Chris Pringle
2009-06-16 16:46 ` Scott Wood
2009-06-16 16:57 ` Chris Pringle
2009-06-16 17:03 ` Scott Wood
2009-06-16 17:43 ` Arnd Bergmann [this message]
2009-06-16 17:49 ` Scott Wood
2009-06-16 18:02 ` Arnd Bergmann
2009-06-17 0:18 ` Benjamin Herrenschmidt
2009-06-17 0:37 ` FUJITA Tomonori
2009-06-17 0:56 ` Leon Woestenberg
2009-06-17 1:08 ` Benjamin Herrenschmidt
2009-06-17 1:13 ` Leon Woestenberg
2009-06-17 1:07 ` Benjamin Herrenschmidt
2009-06-17 7:58 ` Chris Pringle
2009-06-17 13:18 ` Chris Pringle
2009-06-18 11:24 ` Chris Pringle
2009-06-22 14:31 ` AW: " Sergej.Stepanov
2009-06-29 8:11 ` Chris Pringle
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