QoS - Ingress Port Queuing (SP or default) based on CoS?

Question

Guys,
the following URL is excellent for the QoS flow through a 6500. Also had an excellent briefing off a mate in my team :)
http://www.cisco.com/en/US/customer/tech/tk543/tk762/technologies_white_paper09186a00800b0828.shtml
One question on this. It states the following :-
A frame enters the switch and is initially processed by the port ASIC that received the frame. It will place the frame into a Rx queue. Depending on the Catalyst 6000 family line card, there will be one or two Rx queues.
The port ASIC will use the CoS bits as an indicator of which queue to place the frame into (if multiple input queues are present). If the port is classified as untrusted, the port ASIC can overwrite the existing CoS bits based on a predefined value.
The statement "The port ASIC will use the CoS bits as an indicator of which queue to place the frame into"
does this mean that the frame can only be put into the Rx queue based on an L2 (isl, dot1q) CoS value, OR can the frame be place in an Rx queue based on an L3 DSCP or ip prec value? ALSO, what if there is no CoS value, (ie the frame is not from a trunk, ie untagged)
then it goes off for internal DSCP markings (which I understand all about now I hope) :)
Could someone please clear this small point up for me.
Many thx indeed,
Ken

Answer 1

Hey dude, (also thx Simon also)
This is the thing, according to the documentation, the DSCP-COS mappings are for mapping the internal DSCP value on the PFC (i think) which come well after the input queue assignment phase so i would like to think that the input ASIC says what you are implying.
The extrat from the doc is
As mentioned earlier, the switch uses a DSCP value internally to assign a predetermined level of service to that frame. As a frame enters a trusted port, the administrator can configure the port to look at either the existing CoS, IP precedence, or DSCP value to set the internal DSCP value. Alternatively, the administrator can set a predefined DSCP to every packet that enters the port.
it says "the administrator can configure the port to look at either the existing CoS, IP precedence, or DSCP value to set the internal DSCP value" It does not say that it will look at the COS, IPPREC or DSCP to move the incoming packet into the relevant Rx Q?
Am I being a little silly here? Sorry if I am :)
I suppose what I am trying to say is. A frame comes into a switchport that has two queues, SP and default. If it comes in on a non-trunk port (has no CoS marking) how would you determine how to get a frame into a specific Rx queue (if you have two of them) based on CoS?
Kind regards,
Ken