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From: Peter Maydell <peter.maydell@linaro.org>
Date: Mon, 9 Oct 2017 18:03:32 +0100
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Subject: Re: [Qemu-devel] [PATCH 02/17] imx_fec: Do not calculate FEC
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To: Andrey Smirnov <andrew.smirnov@gmail.com>
Cc: qemu-arm <qemu-arm@nongnu.org>, Jason Wang <jasowang@redhat.com>, QEMU Developers <qemu-devel@nongnu.org>, Andrey Yurovsky <yurovsky@gmail.com>

On 9 October 2017 at 15:47, Andrey Smirnov <andrew.smirnov@gmail.com> wrote:
> On Fri, Oct 6, 2017 at 6:48 AM, Peter Maydell <peter.maydell@linaro.org> wrote:
>> This looks a bit odd. Doesn't the hardware calculate the CRC here?
>>
>
> It does, it just seemed to me that since the hardware also has a "CRC
> error" bit in its status register, there would be few if any users of
> the actual calculated CRC value. Given how eTSEC emulation layer gets
> away without calculating CRC I thought that it might be possible to
> have this optimization here as well.

As a general rule QEMU should just emulate what the hardware does
(even if the usual guest software doesn't happen to care about
that corner of the specification).

thanks
-- PMM