ARM AMBA NIC-301 User Manual

ARM DDI 0397G

2-12

ID031010

This section describes how the AMBA Network Interconnect operates and contains the 
following subsections:
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The upsizer function can expand the data width by the following ratios:
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1:2

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1:4

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1:8.

Upsizing only packs write data for write or read transactions that are cacheable. This section 
describes the packing rules for different burst types and acceptance capabilities, and the 
following definitions apply:

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an aligned input burst means that the address is aligned to the output data width word 
boundary, after the network aligns it to the size of the transfer

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an unaligned input burst means that the network does not align the address to the output 
data width word boundary, even after it aligns it to the size of the transfer

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if a transaction passes through, this means that the upsize function does not change the 
input transaction size and type.

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If the network splits input exclusive transactions into more than one output bus 
transaction, it removes the exclusive information from the multiple transactions it creates.

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If multiple responses from created transactions are combined into one response, then the 
order of priority is:
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DECERR is the highest priority

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SLVERR is the next highest priority

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OKAY is the lowest priority.

In the examples in this section, the input data width is 64-bit, and the output data width is 
128-bit, unless otherwise stated. This section describes:
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