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From: Roland Dreier <rdreier@cisco.com>
To: vb <vb@vsbe.com>
Cc: linuxppc-embedded@ozlabs.org
Subject: Re: Allocating uncached memory in 2.6.25(powerpc/440)
Date: Fri, 19 Sep 2008 15:09:35 -0700	[thread overview]
Message-ID: <ada1vzfaiu8.fsf@cisco.com> (raw)
In-Reply-To: <f608b67d0809191456p7193a0bfh3529d9241a304301@mail.gmail.com> (vb@vsbe.com's message of "Fri, 19 Sep 2008 14:56:11 -0700")

 > basically, a block of contiguous memory is allocated. This block is
 > needed to set up some DMA descriptors, so it needs to be uncached, and
 > I thought this is what GFP_DMA flag is for.

No, GFP_DMA doesn't have that meaning.  To allocate uncached memory, use
dma_alloc_coherent().

 - R.

      reply	other threads:[~2008-09-19 22:09 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-09-19 21:47 Allocating uncached memory in 2.6.25(powerpc/440) vb
2008-09-19 21:56 ` vb
2008-09-19 22:09   ` Roland Dreier [this message]

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