Query FPGA device ID from Linux

I think you're looking for the Scan Manager ?

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The scan manager is used to configure and manage the HPS I/O pins, and communicate with the FPGA JTAG test access port (TAP) controller. The scan manager drives the HPS I/O scan chains to configure the I/O bank properties before the pins are used by the peripherals in HPS. The scan manager can also optionally communicate with the FPGA JTAG TAP controller to send commands for purposes such as managing cyclic redundancy check (CRC) errors detected by the FPGA control block. When the scan manager communicates with the FPGA JTAG TAP controller, input on the FPGA JTAG pins is ignored.

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