Due to a problem in the U-Boot bootloader code, the Intel® Stratix® 10 Hard Processor System may report an error similar to the following when attempting to access the Secure Device Manager QSPI flash memory and the configuration clock source is set to the OSC_CLK_1 pin:
SOCFPGA_STRATIX10 # sf probe
SF: Calibration failed (low range)
SF: unrecognized JEDEC id bytes: ff, fc, 82
Failed to initialize SPI flash at 0:0 (error -2)
To avoid this problem, set the configuration clock source to use the Internal Oscillator.