CBASS: this is a crossbar module to provide physical connection among the
initiators and targets
VBUSP interface: a single-issue interface
VBUSM interface: a multi-issue interface
Channel ID: channel ID for interface indicates a logical flow. All the
transactions with the same channel ID coming from the same initiator interface
are consider orthogonal and independent flow.
OrderID: a 4 bits value associated with each transaction. All the
transactions from the same initiator to the same target end point with the same
orderID needs to be executed in order. OrderID is also to be used to select
real-time and non-real time path for the transaction. OrderID 8-15 reserved for
real-time path.
ASEL: Address Selection.
This is an attribution associated with each transaction. Asel can be either used
for select a unique memory map or be used to indicate the IO coherent
transactions.
PrivID: This is an attribute associated with each transaction. The privID
value indicates the security access group. PrivID is either assigned by the ISC
block or driven internally by DMA configuration.
Priv: this is a transaction attribute to determine whether the
transaction is supervisor privilege. Priv =1 indicates the supervisor privilege
and 0 means the user privilege.
ISC block: stands for Initiator Security Control. ISC can add or
overwrite the transaction attributions such as privID, priv and secure.
Region based firewall: this is firewall block based on address region.
The minimal region granularity is 4KB. User can configure each the protection
region and its access privilege.
Channelized firewall: provide protection for a predefined region size, the
predefined region size can be as small as 4B.
QoS block: Quality of Service block allows user to add some additional
sideband signals to the transaction to fine tune the system level performance.