5 Replies Latest reply on Oct 17, 2014 5:44 AM by mhahn

    Where does DFU reside?

    faceplant

      Before I get too aggressive in modifying my Edison I would like to know where the lethal mines are.  I assume (short of JTAG) the lowest level of recovery on the Edison is DFU, but I don't know where the DFU bootloader resides.  Is it a function of uboot, or is it lower level than that.  If I accidentally blow away uboot am I dead in the water?

        • 1. Re: Where does DFU reside?
          rkd

          DFU (Device Firmware Utility) is a host side (PC) utility and not residing on Edison

          It is used for download firmware to device connected on USB.

           

          On the Edison the boot components involved are

          HW->Trusted Boot ROM -> IFWI ->Uboot -> Linux

          Trusted Boot Rom which sits right on top of the HW: It is implemented as on-die silicon based ROM, and performs minimal hardware initialization and boots the IFWI firmware (Integrated Firmware)

          IFWI (integrated firmware Image) - Contains firmware components required for initialization and operation of control units and accelerators within the SOC + first stage bootstrap

          The first stage boot strap loads and runs the OS loader U-boot (second stage bootstrap to continue the booting of the Linux OS.

           

          hope this helps in your understanding.

          • 2. Re: Where does DFU reside?
            faceplant

            Thanks for the information, but there must be an Edison-side DFU (Device Firmware Upgrade) that dfu-util connects to to load the firmware.  It looks to me like it runs before uboot, which means that you could blow away uboot and not brick the Edison.  My question really is if I break uboot will I brick the Edison, or can I always re-flash it via DFU?

            • 3. Re: Where does DFU reside?
              AlexT_Intel

              My personal feeling based on what I see during the boot sequence is that you should be able to restore it in this case. But I don't know for sure, so I wouldn't bet

               

              There's a "<...> usb_dnl_dfu" message before the u-boot kicks in and flashall.bat/sh reflashes all the pieces starting from IFWI, which is what I think implements the DFU board-side. And the sequence above sort of confirms my understanding. rkd do I get it right here?

              • 4. Re: Where does DFU reside?
                rkd

                Yes AlexT is right the flashall.bat (or .sh) ref lashes all the pieces including IFWI, so you are ok!

                • 5. Re: Where does DFU reside?
                  mhahn

                  so you may mark it as answered