AM6442：About DDRSS

Check section 3.3.2 QoS.  Each master can be setup with its own priority using the CBASS_MAP_i.EPRIORITY bit field.  These priorities can then be mapped into the registers mentioned above that provides the priority to the DDRSS

Regards,

James

Hello James,
Thank you for your reply.

I have checked "3.3.2 Quality of Service (QoS)".
Is it possible to set the priority for each master by setting "CBASS_MAP_i [14-12] EPRIORITY"?
However, since there is only a description related to CBASS_MAP_i in this part in the reference manual, the setting method is unknown.
Therefore, I don't know how to specify the master, but is this master and RouteID the same?

Also, there is a description of "Route ID is not related to QoS." In the same sentence, but is it okay to recognize that Route ID information cannot be obtained from the QoS sentence?
Furthermore, the description of the Route ID of Table 3-14 and Table 3-15 is also TBD.
Please provide the priority value of VBUSM associated with RouteID and RouteID to set the priority of the DDR controller.

Regards.

Sorry, i'm mixing up two mechanisms to control priority of transactions

One way to control priority is in the CBASS interconnect with QoS.  Each master that can be assigned a priority will have a CBASS_MAP_i register associated with it.  The current version of the TRM is missing the information on CBASS_MAP_i registers.  This will be in the next revision in April.  If you need it sooner, let me know.  In the interconnect, the RouteID is only used to identify the initiator and route data back to it.  It doesn't have any association with interconnect QoS.  The RouteID table will also be updated in the next TRM revision

The DDRSS has its own priority mechanism (Class of Service) which uses the RouteID and the priority from the interconnect to determine priority of the master.  The transaction's RouteID is first compared with the match registers (R*_MAT) to determine which Range Map (R*_PRI_MAP) to use.  Then, the R*_PRI_MAP maps the interconnect priority (VBUSM priority) to the AXI priority which is used by the DDR controller.  Figure 8-3 in the TRM shows this mapping in a diagram

Regards,

James            

Hello James,
Thank you for your reply.

I would like to know how to prioritize both "CBASS interconnect with QoS" and "DDRSS".

In the priority setting of "DDRSS", I think that the setting values of "Route ID" and "Priority from interconnection" are required.
In the priority setting of "CBASS interconnection with QoS", I think that the information of "CBASS_MAP_i register" are required.

I would like you to provide the following specifications as soon as possible.

--RouteID
--Priority from interconnection
--CBASS_MAP_i register information

Regards.

Hello James.

We are waiting for your reply, so please do so as soon as possible.

Regards.

Hi, we are working on getting this information.

Regards,

james