From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Scott Wood <scottwood@freescale.com>
Cc: Wood Scott-B07421 <B07421@freescale.com>,
Yoder Stuart-B08248 <B08248@freescale.com>,
"qemu-devel@nongnu.org" <qemu-devel@nongnu.org>,
Bhushan Bharat-R65777 <R65777@freescale.com>
Subject: Re: [Qemu-devel] [RFC] Proposal: PCI/PCIe: inbound BAR0 emulation for PCI controller (Root Complex)
Date: Sat, 09 Jun 2012 08:51:10 +1000 [thread overview]
Message-ID: <1339195870.24838.55.camel@pasglop> (raw)
In-Reply-To: <4FD24DAE.6040709@freescale.com>
On Fri, 2012-06-08 at 14:08 -0500, Scott Wood wrote:
> > Yes, that's basically it. The patches allow you to add a set of
> routines
> > that will be used for translating DMA accesses to system memory
> along
> > with map/unmap operations etc...
>
> How easy is it to have multi-level translation -- PCI controller
> translates PCI transactions to host DMA addresses, and the system
> IOMMU
> translates that into a physical address?
Multi level would mean a translation layer at every bridge level, which
sucks big time in term of performances. At the moment the patches
provide a way to hook a translate function at the bus level.
Cheers,
Ben.
next prev parent reply other threads:[~2012-06-08 22:51 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-06-08 9:03 [Qemu-devel] [RFC] Proposal: PCI/PCIe: inbound BAR0 emulation for PCI controller (Root Complex) Bhushan Bharat-R65777
2012-06-08 11:01 ` Benjamin Herrenschmidt
2012-06-08 11:35 ` Bhushan Bharat-R65777
2012-06-08 19:08 ` Scott Wood
2012-06-08 22:51 ` Benjamin Herrenschmidt [this message]
2012-06-11 12:41 ` Bhushan Bharat-R65777
2012-06-08 18:56 ` Scott Wood
2012-06-11 5:05 ` Bhushan Bharat-R65777
2012-06-11 19:15 ` Scott Wood
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