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Table 49: Completer Completion Descriptor Fields (cont'd)
Bit Index
Field Name
Description
79:72
Target Function/Device Number
Device and/or Function number of the Completer Function.
Endpoint mode:
ARI enabled:
•
Bits [79:72] must be set to the Completer Function number.
ARI disabled:
•
Bits [74:72] must be set to the Completer Function number.
•
Bits [79:75] are not used
Upstream Port for Switch use case (Endpoint mode is selected within
the IP):
ARI enabled:
•
Bits [79:72] must be set to the Completer Function number.
ARI disabled:
•
Bits [74:72] must be set to the Completer Function number.
•
Bits [79:75] are not used if the Completion is originating from the
switch itself. These bits must be set to the Completer Device
number where the Completion was originated if the switch is
relaying the Completion (Completer is external to the switch).
This is used with Completer ID Enable bit in the descriptor.
Root Port mode (Downstream Port):
ARI enabled:
Bits [79:72] must be set to the Completer Function number.
ARI disabled:
•
Bits [74:72] must be set to the Completer Function number.
•
Bits [79:75] must be set to the Completer Device number. This is
used with Completer ID Enable bit in the descriptor.
87:80
Completer Bus Number
Bus number associated with the completer function.
Endpoint mode:
•
Not Used
Upstream port for switch use case (Endpoint mode is selected within
the IP):
•
Not used if the completion is originating from the switch itself.
These bits must be set to the completer bus number where the
completion is originated if the switch is relaying the completion
(completer is external to the switch). This is used in conjunction
with Completer ID Enable bit in the descriptor.
Root Port mode (Downstream Port):
•
Must be set to the completer bus number. This is used in
conjunction with Completer ID Enable bit in the descriptor.
Chapter 4: Designing with the Core
PG346 (v3.3) November 16, 2022
CPM Mode for PCI Express
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