Xilinx Zynq-7000 Manual page 8

Chapter 32: Device Security
XILINX CONFIDENTIAL — DISCLOSED UNDER NDA
The PS DAP controller can be permanently bypassed using the "JTAG CHAIN DISABLE" eFuse. The JTAG access
to the PL can be disabled by setting the DISABLE_JTAG configuration option when creating the PL bitstream see
UG628, Command Line Tools User Guide for more information.
33.4.6 Readback
Whenever an encrypted bitstream is loaded into the PL, readback of the internal configuration memory cannot be
performed by any of the external interfaces, including JTAG. The only readback access to the configuration memory
after an encrypted bitstream load is via PCAP-ICAP or ICAP. The PCAP-ICAP and ICAP interfaces are "trusted"
channels since access to these interfaces are from an authenticated PS image or an authenticated PL bitstream.
33.5 Source Documents
Zynq-7000 EPP Technical Reference Manual
UG585 (DRAFT) February 15, 2012
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