Xilinx Zynq-7000 Application Note page 6

Reference System Description
Figure 4 shows the Avnet IIoT starter kit with the MicroZed board mounted on the Avnet
Arduino carrier card. It also shows the Infineon OPTIGA TPM 1.2 SLB 9670 Pmod plugged into
the J2 PS PMOD connector.
X-Ref Target - Figure 4
Figure 4: Avnet IIOT Starter Board with Infineon OPTIGA SLB 9670 TPM Connection
The Infineon OPTIGA SLB 9760 attached to PMOD connector J2 communicates to the
Zynq-7000 AP SoC using the processing system (PS) serial peripheral interface (SPI) driver.
Wind River Pulsar Linux (WRPL) 8.0 runs on MicroZed and includes the strongSwan client
software. Prior to booting WRPL, the Zynq-7000 AP SoC runs the FSBL. The FSBL runs pre-boot
authentication on the BootROM and FSBL.
The FSBL then executes PCR extend commands to log BootROM and FSBL SHA-1 digests into
the PCR[0] and PCR[4]. The PCR extend command is similar to a write command. It differs from
the write value in that the value loaded into the PCR is an SHA of all cumulative SHA values
loaded into the PCR. Because a PCR extend rather than a write is done, an adversary is unable
to read PCRs and get "expected" values.
XAPP1309 (v1.0) March 7, 2017
www.xilinx.com
X18724-020317
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