From mboxrd@z Thu Jan  1 00:00:00 1970
Subject: Re: Problems with dma_alloc_coherent()
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Adrian Cox <adrian@humboldt.co.uk>
Cc: Paul Mackerras <paulus@samba.org>,
	John Whitney <jwhitney-linuxppc@sands-edge.com>,
	Linux/PPC Development <linuxppc-dev@lists.linuxppc.org>
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Date: Mon, 05 Apr 2004 08:56:19 +1000
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> Actually, they are extremely common in the embedded market. On my desk I
> have three Linux systems with this class of DMA engine: an MPC107/7410,
> an ARM9 from Cirrus, and an ARM9 from TI. Most system-on-a-chip
> processors have DMA engines which can move between any two of memory,
> PCI, and internal peripherals.

Right, but in this case, those systems also usually don't have an iommu
and usually provide a simple 1:1 mapping between memory and bus addresses ;)

Ben.


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