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Subject: FSL 64-bit DMA window question
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Zang Roy-R61911 <r61911@freescale.com>
Date: Fri, 07 Jun 2013 17:05:27 +1000
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Hi Folks !

Is there any specific reason why you chose 1T (40 bit) as the location
of the 64-bit DMA window ?

It happens that most current radeon adapters cannot DMA there, they have
a 40-bit DMA limit. I seem to be getting things to work fine using a
39-bit window, but I suppose that might collide with something else ?

Can you guys consider changing the default ?

Cheers,
Ben.