A10.3 Attributes of the CHI master interface
The table lists the possible values for the read and write issuing capabilities if the processor includes four
cores.
n Number of cores.
m 1 if the processor is configured for the ACP interface, 0 if it is not.
w (write issuing capability)+1.
Table A10-3 Attributes of the CHI master memory interface
Attribute Value Comments
Write issuing
capability
Configuration
dependent
The maximum number of writes varies, depending on the configuration of the processor:
• The number of cores.
• The presence of the L2 cache.
If no L2 cache is configured:
One
core
5 outstanding writes.
2-4
cores
8 outstanding writes.
If an L2 cache is configured:
One
core
7 outstanding writes.
2-4
cores
10 outstanding write.
A cluster with four cores, with L2 cache, can issue 10 outstanding transactions. A processor
with one core, without L2 cache, can issue five outstanding transactions.
All outstanding transactions use a unique ID.
Read issuing
capability
8n + 4m + 1 8 for each core in the cluster including up to:
• 8 data linefills.
• 4 Non-cacheable or Device data reads.
• 1 Non-cacheable TLB page-walk read.
• 3 instruction linefills.
• 5 coherency operations.
• 1 barrier operation.
• 8 DVM messages.
If an ACP is configured, up to 4 ACP linefill requests can be generated. 1 barrier operation
is generated from the cluster.
Exclusive thread
capability
n Each core can have 1 exclusive access sequence in progress.
A10 CHI Master Interface
A10.3 Attributes of the CHI master interface
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