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From: Paolo Bonzini <pbonzini@redhat.com>
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Date: Fri, 19 Feb 2016 18:17:37 +0100
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Subject: Re: [Qemu-devel] [PATCH v1 1/2] qdev-monitor.c: Register reset
 function if the device has one
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To: Peter Maydell <peter.maydell@linaro.org>
Cc: Markus Armbruster <armbru@redhat.com>, "qemu-devel@nongnu.org Developers" <qemu-devel@nongnu.org>, Alistair Francis <alistair.francis@xilinx.com>, Peter Crosthwaite <crosthwaitepeter@gmail.com>, Christopher Covington <cov@codeaurora.org>, =?UTF-8?Q?Andreas_F=c3=a4rber?= <afaerber@suse.de>, Li Guang <lig.fnst@cn.fujitsu.com>



On 19/02/2016 11:55, Peter Maydell wrote:
>> Any abstraction we have in QEMU should have at least a parallel (though
>> > it need not be the same) in real hardware.  Reset signals _do_ propagate
>> > along buses, or at least along some buses, so "debusifying" reset seems
>> > like a counterproductive goal to me.
> Reset for some buses propagates along buses, but not in all
> cases.

Agreed.  But still this doesn't change the fact that "debusifying" reset
is a non-goal.

> In any case our current "reset" semantics are "power on
> reset", not any kind of driven-by-hardware-reset-lines reset.

It depends.  There are several cases (PCI, SCSI) where qdev_reset_all is
used from within the code in order to provide hardware reset semantics.

Paolo