Once you extract the tgz file, a bin file should appear.
You can program the firmware using any host with an IB connection to that switch.
Simply run the ibswitches command to retrieve all the LIDs of the switches in the fabric.
Once you have the LID, use flint to program the firmware.
flint -d lid-<lid> -i <path to firmware> b
eyals:~ # ibswitches
Switch : 0x0002c9020040fc28 ports 36 "Infiniscale-IV Mellanox Technologies" base port 0 lid 44 lmc 0
flint -d lid-44 -i /tmp/firmware.bin b
don't forget to reboot the switch after the new firmware is programmed.
You can reset the switch remotely as well by the way with the flint -d lid-44 swreset command
When I extract "InfiniScale_MT43132_Firmware_5_6_0.tgz I get a folder called "ucode-43132-5.6.0. Inside of that folder it has files called main_anata.ccf and start1_anafa.hx. It appears to be source code for the firmware, not the actual firmware.