The Arria® 10 device performs a Power-Up Calibration at startup, but requires a stable supply of CLKUSR and Reference Clock (Refclk) supplied to each Transceiver.
(Reference) Arria® 10 Transceiver PHY User Guide
https://docs.altera.com/r/docs/683617/21.1/arria-10-transceiver-phy-user-guide/calibration?tocId=5nBovPLWZ~WVDBBsbc266Q
(see section 7. Calibration)
Excerpt
Arria 10 devices use CLKUSR for transceiver calibration. To successfully complete the
calibration process, the CLKUSR clock must be stable and free
Also, all reference clocks driving transceiver PLLs (ATX PLL, fPLL,
CDR/CMU PLL) must be stable and free Also, all reference clocks driving transceiver PLLs (ATX PLL, fPLL, CDR/CMU PLL) must be stable and free at start of FPGA configuration.
If this is not followed, Transceiver Calibration may not be performed, PCIe Linkup may not work properly, etc. Please refer to the following Knowledge Database (KDB) for more information related to the
PCie.
Why might Arria 10 Transceiver calibration fail?
https://community.altera.com/kb/knowledge-base/why-might-intel%C2%AE-arria%C2%AE-10-transceiver-calibration-fail/344385
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Category: PCI-Express
Tools: -
Device: Arria® 10