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Sender: Jiri Slaby <jirislaby@gmail.com>
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Date: Mon, 13 Oct 2014 10:32:13 +0200
From: Jiri Slaby <jslaby@suse.cz>
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Subject: Re: [Qemu-devel] [PATCH 1/1] pci-host: add educational driver
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To: Claudio Fontana <claudio.fontana@huawei.com>, qemu-devel@nongnu.org
Cc: Peter Maydell <peter.maydell@linaro.org>, Alvise Rigo <a.rigo@virtualopensystems.com>

On 10/10/2014, 04:54 PM, Claudio Fontana wrote:
> Hello,
> 
> On 10.10.2014 14:09, Jiri Slaby wrote:
>> I am using qemu for teaching the Linux kernel at our university. I
>> wrote a simple PCI device that can answer to writes/reads, generate
>> interrupts and perform DMA. As I am dragging it locally over 2 years,
>> I am sending it to you now.
>>
>> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
> 
> is this supposed to be architecture independent, or is it X86-specific?

Hi,

I did not plan it to be only x86 specific. If you see any problems, I
will fix them.

> Also at first glance I see multiple 32bit variables used to hold addresses,
> is this 32bit-only?

No, the DMA addresses are on purpose 32-bit: to teach the people always
set the dma mask properly in the driver. This driver copies COMBO6x
devices (liberouter.org) behaviour which I used until the cards got
obsoleted (hard to find PCI-X slots nowadays).

I can make this configurable if you wish.

> I wonder if this work could be merged / integrated with the Generic PCI host patches that are flying around since some time...

Could you point me to some?

thanks,
-- 
js
suse labs