Figure 129 Wcb Operation - Microchip Technology Microsemi SmartFusion2 User Manual

DDR Bridge
Figure 129 • WCB Operation
5.1.2.2 Read Buffer
The DDR bridge has a read buffer for each master to hold the fetched DDR burst data. Each read buffer
has a configurable burst size of 16 or 32 bytes. The read buffer initiates a DDR burst size request for
reads in the bufferable region, regardless of the size of request from the master. Each read buffer is
associated with one specific master for reading; it does not check the read addresses of other masters to
determine whether that data can be read from the read buffer-there is no cross buffer read access. The
following illustration shows the flow chart for read operation.
matching with WCB
Buffer the data based on
NO
Write the data in WCB to AXI slave
Microsemi Proprietary UG0446 User Guide Revision 7.0
Start
NO
Write request = 1
YES
NO
Bufferable
Write Request?
YES
NO
Write address is
tag/WCB empty?
YES
WCB tag
WCB full/
timeout
YES
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