Re: [PATCH -mm 0/2] RapidIO: Changes to handling of RIO switches

From: Micha Nelissen
Date: Mon Oct 25 2010 - 16:07:04 EST


Bounine, Alexandre wrote:
Micha Nelissen <micha@xxxxxxxxxxxxxx> wrote:
that switch. The tag uses one extra bit to identify the device as a
switch instead of an endpoint. This provides the information to
unambiguously identify a switch from an endpoint.

OK taking away #2. But do not see how it justifies storing two values of
destid.

I look at it this way: it prevents the need for another layer of indirection: translating component tag to a destid.

And you have just confirmed using CT for unique identification.

That's correct, but I never said (intended to say) I didn't.

We
simply have differences in interpretation of CT: you are using component
tag to pass unique identification and I am using CT as a unique
identification. I prefer not to assume any relationship between routing
information and the component tag.

Why no relation? My experience is that during debugging it's useful to have the destid directly at hand, it's just very practical. (Otherwise any drawing of a random network would need two "identification" numbers per drawn node: the component tag (true identification), and destid since that's what everyone uses to identify a device, what needs to programmed into the LUTs of a switch, identification in sysfs, etc.).

Micha
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