BAR Initialization Tasks - 1.0 English

Versal Adaptive SoC Integrated Block for PCI Express LogiCORE IP Product Guide (PG343)

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1.0 English
Table 1. BAR Initialization Tasks
Name Input(s) Description

Performs a standard sequence of Base Address Register initialization tasks to the Endpoint device using the PCI Express fabric. Performs a scan of the Endpoint PCI BAR range requirements, performs the necessary memory and I/O space mapping calculations, and finally programs the Endpoint so that it is ready to be accessed.

On completion, the user test program can begin memory and I/O transactions to the device. This function displays to standard output a memory and I/O table that details how the Endpoint has been initialized. This task also initializes global variables within the Root Port Model that are available for test program usage. This task should only be called after TSK_SYSTEM_INITIALIZATION.


Performs a sequence of PCI Type 0 Configuration Writes and Configuration Reads using the PCI Express logic to determine the memory and I/O requirements for the Endpoint.

The task stores this information in the global array BAR_INIT_P_BAR_RANGE[]. This task should only be called after TSK_SYSTEM_INITIALIZATION.


Performs memory and I/O mapping algorithm and allocates Memory 32, Memory 64, and I/O space based on the Endpoint requirements.

This task has been customized to work with the limitations of the PIO design and should only be called after completion of TSK_BAR_SCAN.

TSK_DISPLAY_PCIE_MAP None Displays the memory mapping information of the Endpoint core PCI Base Address Registers. For each BAR, the BAR value, the BAR range, and BAR type is given. This task should only be called after completion of TSK_BUILD_PCIe_MAP.