SPRZ580 December 2024 AM62D-Q1
OSPI: Controller PHY Tuning Algorithm
The OSPI controller uses a DQS signal to sample data when the PHY Module is enabled. However, there is an issue in the module which requires that this sample must occur within a window defined by the internal clock. Read operations are subject to external delays, which change with temperature. In order to guarantee valid reads at any temperature, a special tuning algorithm must be implemented which selects the most robust TX, RX, and Read Delay values.
The workaround for this bug is described in detail in SPRACT2. To sample data under some PVT conditions, it is necessary to increment the Read Delay field to shift the internal clock sampling window. This allows sampling of the data anywhere within the data eye. However, this has these side effects: