The AHB5 upsizer allows a narrow AHB5 bus master to connect to a double-width AHB5 slave.
Due to the nature of upsizing, there is no need for HTRANS conversion or dividing a wide transfer to two narrow ones such as in case of the AHB5 downsizer.
Figure 2.31 shows the AHB5 upsizer module.
The HRDATA multiplexing is done in a way based on the endianness configuration setting as described in the AHB5 standard and the HADDR of the current transaction.
The HWDATA is replicated on both halves of the wide AHB5 bus, regardless of endianness setting.