programming FELIX flash: "fflash -f 0 mcsfile.mcs prog"

fflash -f 0 ~/gtm/felix-firmware-sync2018-08/output/FLX711_GBT_RM0403_4CH_CLKSELECT_GIT_mvtx_rm-4.4_4_190227_19_04.mcs prog

now if you power-cycle, FELIX will load the new firmware

you can write to different partitions of the flash by changing the "-f 0" flag, and then there are jumpers that select which partition FELIX boots from - haven't tried this
====
booting FELIX from flash without power-cycle:

supposed to be possible with fflash -I, but this uses I2C over PCIe

yum install i2c-tools

X10DRG-Q motherboard (dual-socket server) has I2C jumpers, these must be set to enable I2C to PCIe
page 2-37: https://www.supermicro.com/manuals/motherboard/C612/MNL-1677.pdf

some devices show up now (i2cdetect 0) but still doesn't work - expect to see the PCA9546A at 0x70