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Date:      Fri, 11 Sep 2015 10:44:22 -0400
From:      "Chad J. Milios" <milios@ccsys.com>
To:        Shane Ambler <FreeBSD@ShaneWare.Biz>
Cc:        Ernie Luzar <luzar722@gmail.com>, "freebsd-questions@freebsd.org" <freebsd-questions@freebsd.org>
Subject:   Re: USB physical ports
Message-ID:  <BCE7CC60-B15B-4FFA-AD19-96C8BA9424BD@ccsys.com>
In-Reply-To: <55F2A2B2.4090801@ShaneWare.Biz>
References:  <55F1A507.70402@gmail.com> <2091716.bhpPQfPjgk@amd.asgard.uk> <55F216CB.6040606@gmail.com> <55F2A2B2.4090801@ShaneWare.Biz>

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> On Sep 11, 2015, at 5:45 AM, Shane Ambler <FreeBSD@ShaneWare.Biz> wrote:
>=20
>> On 11/09/2015 09:18, Ernie Luzar wrote:
>> Dave wrote:
>>>> On Thursday 10 September 2015 11:43:03 Ernie Luzar wrote:
>>>> Hello List;
>>>>=20
>>>> I have 6 physical ports on my PC box. The boot time messages seem to
>>>> say that one of those ports is 480Mbps High Speed USB v2.0.
>>>>=20
>>>> How do I determine which physical USB port is the 480Mbps High Speed
>>>> port?
>=20
> I think inserting a device is the only way to identify which port it is
> inserted into, use usbconfig to see what is connected at what speed.

Yeah unfortunately there is little rhyme or reason between device tree the k=
ernel enumerates as seen in dmesg output and physical ports on front/back/si=
des/inside computer. Some of the things FreeBSD sees may not be USB ports/hu=
bs/devices at all, in the typical sense, and instead are certain features of=
 your motherboard that just happen to be connected by USB at an electric and=
/or protocol level. And some of the real physical ports actually get shared b=
y USB "hubs" built into the motherboard physically or simulated by mixtures o=
f firmware and other types of bridges and busses.

Test what you need to test in order to be sure your system will run how you r=
eally intend. 480 Mbps or 5 Gbps on each port one at a time may work great b=
ut then down the road you discover you can only do a total of x bps to ports=
 a thru b while simultaneously doing y bps thru ports c thru d and the combi=
nations are endless. Many desktop/server mobos have numerous extra USB conne=
ctors on the mobo, minus the actual ports, (for ten cent adapters added once=
 you need them or tiny devices meant for those internal connectors).

Good mobos from good manufacturers should have block diagrams you can trust b=
ut matching them up to actual kernel probes is not an exact or consistent sc=
ience from product SKU to product SKU and you'd be darn lucky when the manuf=
acturer doesn't mix it up between different batches of the same SKU.=



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