Credit Descriptor Context Structure - 1.0 English

Versal ACAP DMA and Bridge Subsystem for PCI Express Product Guide (PG344)

Document ID
PG344
Release Date
2022-05-20
Version
1.0 English
Table 1. Credit Descriptor Context Structure Definition
Bit Bit Width Field Name Description
[31:16] 16 reserved Reserved
[15:0] 16 credt

Fetch credits received.

Applicable if fetch credits are enabled in the software context.

The credit descriptor context is for internal DMA use only and can be read from the indirect bus for debug. This context stores credits for each queue that have been received through the Descriptor Credit Interface with the CREDIT_ADD operation. If the credit operation has the dsc_crdt_in_fence bit set to 1, credits are added only as the read request for the descriptor is generated.