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Subject: Re: [PATCH] katmai.dts: extend DMA ranges; add dma/sysace nodes
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Yuri Tikhonov <yur@emcraft.com>
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Date: Thu, 13 Nov 2008 20:25:52 +1100
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Cc: linuxppc-dev@ozlabs.org, Detlev Zundel <dzu@denx.de>,
	Wolfgang Denk <wd@denx.de>, Ilya Yanok <yanok@emcraft.com>
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On Thu, 2008-11-13 at 11:49 +0300, Yuri Tikhonov wrote:
> Hello,
> 
> This patch extends DMA ranges for PCI(X) to 4GB, so that it could
> work on Katmais with 4GB RAM installed.

And where do you put MMIO ?

The 32 bit part of the PCI space need to be split between MMIO and DMA. 

Ideally, for 64-bit capable DMA, device, we should create a second DMA
range mapping the whole memory at something like 1T or so on PCI, and
keep a smaller (ie. 2G) DMA range for 32-bit only devices backed with
swiotlb.

Cheers,
Ben.