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Date: Fri, 19 Jan 2007 13:48:22 -0600 (Central Standard Time)
From: T Ziomek <ctz001@email.mot.com>
To: Reyneke <reynekejunk@hotmail.com>
Subject: Re: Howto use PPC4xx memory to memory DMA
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On Fri, 19 Jan 2007, - Reyneke wrote:
> Here are a few things to check:
>
> 1. Your memory destination and source addresses are contiguous. You can get 
> this using something like:
>
> mem = (void*)__get_free_pages(GFP_KERNEL | GFP_DMA, get_order(size));
>
> 2. Your source and dest addresses are _bus_ addresses. You can get these by:
>
> source = virt_to_bus((u32 *)mem);

The above contradicts an email by Ben H back on 22 Dec:
<http://ozlabs.org/pipermail/linuxppc-embedded/2006-December/025546.html>
But I don't know enough to resolve the conflict...

Tom
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